US20060110080A1

US20060110080A1 - Packages and structures with selective dosing of active agent

Info

Publication number: US20060110080A1
Application number: US11/312,208
Authority: US
Inventors: Toby Thomas; Nathan Kolovich; Craig Cappel
Original assignee: Pactiv LLC
Current assignee: Pactiv LLC
Priority date: 2002-02-27
Filing date: 2005-12-19
Publication date: 2006-05-25
Also published as: CN101331072A; CA2632571A1; EP1979252A1; WO2007073542A1

Abstract

Packages and structures with selective dosing of active agents are described. The at least one active agent includes a freshness-extension agent to inhibit spoilage of perishable product disposed in the package, an odor management agent to reduce, mask, or neutralize odors from garbage or waste disposed in the package, a color indicator to indicate the status of one or more other active agents, or another type of agent. Selective dosing is achieved by covering the active agent or agents by a plurality of covers. Some of these covers may be walls of a package itself.

Description

REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. patent application Ser. Nos. 11/055,575 and 11/055,574, each of which filed Feb. 10, 2005, is currently pending and is a continuation-in-part application of U.S. patent application Ser. No. 10/375,188 filed on Feb. 26, 2003, which is currently pending and claims the benefit under 35 U.S.C. § 119(e) of U.S. Patent Application No. 60/359,874 filed on Feb. 27, 2002. U.S. patent application Ser. Nos. 11/055,575 and 11/055,574 also each claim the benefit under 35 U.S.C. § 119(e) of both U.S. Patent Application No. 60/543,344 and U.S. Patent Application No. 60/543,345 filed on Feb. 10, 2004, to which the present application also claims priority.
Each of the foregoing applications is expressly incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention relates to packages and structures, and methods for releasing active agents in such packages. More specifically, the present invention relates to selective dosing of active agents, such as freshness-extension agents, odor management agents, colored indicators and other functional agents, and structures and methods for releasing such active agents to extend the freshness of perishable products and manage or control the odor related to such products disposed within such packages.

BACKGROUND OF THE INVENTION

The use of packages for a number of household and industrial purposes has gained wide acceptance. For example, bags and containers are commonly used by commercial entities and consumers to store perishable products and items. Also for example, bags or liners are commonly used in industrial settings and households to collect garbage or waste.
Reclosable packages, such as food containers with fitted or hinged lids, and bags with push to close or slider fasteners, are a great convenience to suppliers and consumers of pre-packaged perishables, especially for products such as luncheon meats and cheeses where, typically, only a portion of the product is used at any given time. Reclosable packages are also especially convenient for in-home use to store leftover perishable products. A problem with these reclosable packages, however, is that they do not contain any feature that serves to extend the time period that the perishable can be stored in the package and remain fresh. Thus, the contents of the package may spoil sooner and, if so, the contents will be no longer suitable for human consumption. The cost of perishable spoilage is a significant problem for both consumers and commercial users of reclosable packages.
One attempt to address the problem of perishable spoilage has involved using layered tamper resistant seals that are substantially impermeable to oxygen. In this type of system, as soon as the packaging is first opened, the seal is broken and does not further inhibit spoilage of the perishable. This type of system thus addresses only the issue of perishable spoilage before the package is initially opened, and does not serve the in-home user who is placing leftover perishable products into the storage bags. A need therefore exists for a package with a feature that inhibits perishable spoilage. A need further exists for a system or package that allows for selection and control of the inhibitor to be used.
Packages such as thermoplastic bags or liners are also commonly used as waste or garbage bags. Generally, such bags are constructed from a structure having two layers of thermoplastic film joined along three sides and having a mouth formed along the fourth side. This basic structure has been adapted to a range of sizes and configurations that vary with the intended use of the bag.
A garbage bag or liner is often used to collect waste that can and often does produce unpleasant odors. To address this problem, manufacturers have combined a scented resin with one or more polymeric resins during formation of such bags. The scented resin is therefore distributed uniformly throughout the bag. Such a waste bag assists in masking, neutralizing, and/or reducing at least some of the odors.
However, such waste bags can present a number of disadvantages. For instance, because the scented resin is distributed throughout the bag, the scent is not concentrated where a user is likely to encounter the unpleasant odors (e.g., the mouth of the bag). Further, manufacturing difficulties can arise from such bags. For example, to obtain a desired amount of scent proximate the mouth of the bag, an excess of scent material may need to be distributed throughout the remainder of the bag, which can result in an overpowering scent. Of course, if an insufficient amount of scent material is used, the scent provided may not be suitable to mask, neutralize, or reduce the unpleasant odors. Additionally, because the scented resin used in such garbage bags is likely to be more expensive than other polymeric resins used in forming the garbage bags, it can be economically undesirable to distribute relatively equal amounts of scented resin throughout the bag. A need therefore exists for a package with a feature that manages odor without such disadvantages.

SUMMARY OF THE INVENTION

Packages and structures for selectively dosing active agents are disclosed and claimed herein.
Generally, each of the disclosed packages of the present invention includes at least one wall having an active agent associated therewith. For example, the package can be in the form of a bag having two body panels. When in the form of a rigid resealable container, the package includes at least a bottom wall and a side wall, as well as a top wall or lid, if desired. The term “wall,” as used herein is intended to describe any of the bottom, side or top walls. The package also can include at least one wall formed as a food wrap. The active agents used can include one or more types of active agents, each having the similar or different functions. For example, the active agent can be a freshness-extension or antimicrobial agent, odor management agent, color indicator, spoilage indicator, fragrant and variations or mixtures thereof. The active agent can include an isothiocyanate compound for freshness-extension by way of antimicrobial function, and may further include an acid.
In accordance with one aspect of the invention, a package is provided, which includes a wall forming at least a portion of the package and an active agent disposed in a predetermined region of the wall. A plurality of removable covers cover the predetermined region, wherein each removable cover covers an area less than an entire area of the predetermined region. The active agent can be disposed, for example, integrated into the material of the wall, in a layer extruded with the wall or in a coating applied to the wall. Alternatively, the active agent can be disposed by a separate agent structure attached to the wall, using a variety of different techniques. Being integrated with the wall of the package, the active agent can thus be disposed on or in a surface of the package.
When disposed in the form of a separate agent structure, a base layer also is provided. The base layer can be made of a diffusion material with the active agent contained therein, and/or can have the active agent disposed between the base layer and the removable covers. Alternatively or additionally, a diffusion layer can be disposed between the base layer and the removable covers and/or a barrier layer can be provided on the base layer opposite the removable covers. In a preferred embodiment, the barrier layer, base layer and diffusion layers are made of polypropylene, polyethylene and ethylmethyl acrylate, respectively.
The separate agent structure can be in the form of a patch, a tape or a pouch. By providing an adhesive, heat or other mode of attachment, the structures can be adhered or sealed to a body panel of the package, or alternatively can simply be placed within the package. If attached to a wall or body panel of a package, such attachment can be facilitated by an adhesive, cohesive, fusion or weld connection.
The removable cover can include a peelable area to facilitate removal by a user, such as at a corner of the removable cover. Two or more adjacent removable covers can be joined together along a line of weakness, or, in the alternative, can be completely separate components that abut or overlap one another. The covers can be separately attached proximate the predetermined region in any of a variety of techniques including, but not limited to, adhesion, cohesion and static attachment. The plurality of removable covers can be attached to all or a portion of the predetermined region and/or to a surface of the wall proximate the predetermined region.
Each removable cover can further include a diffusion layer and/or a barrier layer which, preferably are made of ethylmethyl acrylate and polypropylene, respectively. The at least one removable cover can further include an outer barrier layer separable from the diffusion layer, such that the outer barrier layer is capable of being removed from the predetermined region separately from the diffusion layer.
The package of the invention can be a bag, wherein the wall forms at least a portion of a pair of opposing panels joined together along opposing sides and a bottom bridging the sides. The bag can further include a reclosable fastener extending along a mouth formed opposite the bottom. Further in accordance with the invention, the predetermined region can be located on one of the pair of opposing panels, where at least one of the plurality of removable covers is further secured to the panel opposite the predetermined region. In this manner, the at least one removable cover is removed from the predetermined region when the opposing panels are spaced from each other. That is, one or more covers can be attached to an opposing side of the bag, such that when the bag is opened, part of the active agent (or the diffusion layer covering it) is automatically exposed to the environment within the bag, thereby activating the active agent. Such opposing walls preferably are formed of a barrier material.
In accordance with another aspect of the invention, a wrap material is provided, which has a web material, an active agent disposed in a predetermined region of the web material, and a plurality of removable covers at least partially covering the predetermined region. Each removable cover generally covers an area less than an entire area of the predetermined region. The web material can be made of materials including, but not limited to ethylene vinyl alcohol (EVOH), polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), Nylon and paper laminates, and thermoplastic materials such as polyethylene (PE), polypropylene (PP), polystyrene (PS), PET nylon and blends and laminates thereof.
In accordance with still another aspect of the invention, an agent structure is provided, which includes a base layer with an active agent in a predetermined region, and a plurality of removable covers covering the predetermined region, wherein each removable cover covers an area less than an entire area of the predetermined region. The characteristics and relationships of the removable covers are similar to those previously described.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a mouth portion of a reclosable package or bag with the opposing body panels attached to respective fin portions according to one embodiment of the present invention;
FIG. 2 is a perspective view of the reclosable package incorporating the mouth portion depicted in FIG. 1 in which the reclosable fastener or zipper has a slider mechanism being opened and the one-time breakable element being partially opened according to another embodiment;
FIG. 3 a is a partial cross-sectional view of one side of a reclosable package or bag comprising a polymeric structure with one layer according to one embodiment of the present invention;
FIG. 3 b is a partial cross-sectional view of one side of a reclosable package or bag comprising a polymeric structure with two layers according to one embodiment of the present invention;
FIG. 3 c is a partial cross-sectional view of one side of a reclosable package or bag comprising a polymeric structure with three layers according to one embodiment of the present invention;
FIG. 3 d is a partial cross-sectional view of one side of a reclosable package or bag comprising a polymeric structure with two layers according to another embodiment of the present invention;
FIG. 4 is a partial cross-sectional view of one side of a reclosable package or bag according to another embodiment of the present invention;
FIG. 5 is a partial cross-sectional view of one side of a reclosable package or bag according to a further embodiment of the present invention;
FIG. 6 is a partial cross-sectional view of one side of a reclosable package or bag according to yet another embodiment of the present invention;
FIG. 7 is a partial cross-sectional view of one side of a reclosable package or bag according to yet a further embodiment of the present invention;
FIG. 8 is a partial cross-sectional view of one side of a reclosable package or bag according to another embodiment of the present invention;
FIG. 9 a is a partial cross-sectional view of one side of a reclosable package or bag that includes a polymeric structure with four layers according to one embodiment of the present invention;
FIG. 9 b is a partial cross-sectional view of one side of a reclosable package or bag that includes a polymeric structure with six layers according to one embodiment of the present invention;
FIG. 10 a is a partial cross-section view of two sides of a reclosable package or bag that includes two polymeric structures that each comprise two layers according to one embodiment of the present invention;
FIG. 10 b is a partial cross-section view of two sides of a reclosable package or bag that includes two polymeric structures that each comprise two layers according to another embodiment of the present invention;
FIG. 10 c is a partial cross-section view of two sides of a reclosable package or bag that includes two polymeric structures that each comprise three layers according to one embodiment of the present invention;
FIG. 11 a is a partial cross-section view of two sides of a reclosable package or bag with a polymeric structure disposed there between, in which the polymeric structure includes a one-time breakable element.
FIG. 11 b is a partial cross-section view showing the reclosable package or bag of FIG. 11 a after breakage of the one-time breakable element;
FIG. 12 a is a partial cross-section view of two sides of a reclosable package or bag, in which one side includes a polymeric structure that comprises two layers, and in which the polymeric structure is connected to the other side by a removable element;
FIG. 12 b is a partial cross-section view showing the reclosable package or bag of FIG. 12 a after removal of the removable element;
FIG. 13 is an isometric view of one embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 14 is an isometric view of another embodiment of an agent structure having a plurality of dosing regions and a singe dedicated cover in accordance with the invention.
FIG. 15 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 16 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 17 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 18 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 19 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 20 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 21 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 22 a is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention;
FIG. 22 b is a side view of the embodiment of FIG. 22 a;
FIG. 23 is an isometric view illustrating a plurality of removable covers in accordance with the invention;
FIG. 24 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention; and
FIG. 25 is an isometric view of another embodiment of an agent structure having plurality of covers in accordance with the invention.

DETAILED DESCRIPTION

The present invention relates to packages, packaging materials, and other related structures with an active agent incorporated therein. As such, the invention has applications for various flexible and rigid containers and packages, such as reclosable plastic bags, waste bags and liners, rigid trash containers, air-tight containers, lunch boxes, and packaging wraps and foils commonly used for perishable packaging or perishable covering.
As used herein, the term “package” can be understood to include any kind of package or container, such as flexible plastic bags and rigid containers, as well as foils or wraps commonly used to package or store perishable items.
As used herein, the term “active agent” can be understood to include any agent, ingredient, or composition that provides an enhancing or beneficial effect within a package or container. An active agent can include a “freshness-extension” agent for extending the freshness or shelf life of food products or other perishables stored in a package, an “odor management” agent for masking, neutralizing and/or reducing odors from the package, or another functional agent. An active agent can include an atmosphere modifier, e.g., a drying agent, a water absorbing agent, or a gas releasing agent; an enhancer, e.g., a flavor enhancer, an odor enhancer, or an agent that enhances any other function, such as water absorption, insulation, or microwave cooking; or an inhibitor which inhibits or deters a certain condition, e.g., a spoilage inhibitor, a fungus inhibitor, a soil inhibitor, a flame inhibitor, a UV inhibitor, a freezer burn inhibitor, or an anti-static agent. An active agent can include an indicator, e.g., an indicator of food ripeness or spoilage, or of contamination, temperature, moisture, modified atmosphere, or the presence of particular gas or a compound in the atmosphere, or used in conjunction with such an indicator.
Each of the active agents of the present invention can be used in combination with a package. More specifically, each freshness-extension agent of the present invention can be used to inhibit spoilage of food products or other perishables in the package, and each odor management agent of the present invention can be used to reduce, neutralize, and/or mask odors from the package. Each of the active agents of the present invention can be disposed in the environment of the package, e.g., disposed in the form of a coating, patch, pouch, or tape that is attached to a component of the package; extruded with a component of the package; sprayed, brushed, coated, laminated, or stamped onto a component of the package; impregnated into a component of the package; and/or distributed in the material of a component of the package, such as in the form of microcapsules.
For purposes of illustration and not limitation, the freshness-extension agents of the present invention can be disposed in the environment of a polymeric bag for storing perishable items. The polymeric bag can be intended for consumer storage of food products (e.g., leftover food products) or applications, such as “form, fill, and seal” food packaging operations. The polymeric bags can include non-reclosable and reclosable polymeric bags. Reclosable polymeric bags are typically made to be reclosable via reclosable elements or fasteners, such as resealable adhesive or cohesive seals, mated tracks, and mated dimples. The mated tracks can be opened and closed by applying finger pressure or by using an auxiliary device, such as a slider. Some examples of reclosable polymeric bags include the bags disclosed in U.S. Pat. Nos. 5,067,208 and 6,147,588 and U.S. Patent Application Publication No. 2004/0066985, the contents of which documents are expressly incorporated by reference herein in their entireties.
Further for purposes of illustration and not limitation, the freshness-extension agents of the present invention can also be disposed in the environment of a rigid package for storing perishables, such as bakery containers, deli containers, fruit containers, lunch boxes, and roaster containers. Some examples of containers include containers disclosed in U.S. Pat. Nos. 6,042,586, 6,257,401, 6,349,857, 6,644,494, 6,845,878 and U.S. Patent Application Publication Nos. 2004/0074902 and 2005/0000966, the contents of which documents are expressly incorporated by reference herein in their entireties.
Additionally for purposes of illustration and not limitation, the odor management agents of the present invention can be used in the environment of bags, liners and rigid trash containers for collecting garbage or waste and other containers for collecting items with undesirable odors, such as laundry and diapers. Such waste bags can include a tie feature that assists in closing the bag or liner securely, forming a handle for carrying the bag or liner to be disposed, and/or facilitating the opening of the bag or the liner. Some examples of waste bags include the bags disclosed in U.S. Patent Application Publication No. 2003/0223657, the contents of which document are expressly incorporated by reference herein in its entirety.
Illustrative embodiments will now be described to provide an overall understanding of the disclosed packages and related structures and active agents. For purposes of illustration and not limitation, the packages of the present invention are described in the context of reclosable polymeric bags. One or more examples of the illustrative embodiments are shown in the drawings. Those of ordinary skill in the art will understand that each disclosed bag having an active agent can be adapted and modified to provide alternative embodiments of bags, containers, and other packages with active agents for other applications, and that other additions and modifications can be made to the disclosed packages and active agents without departing from the scope of the present disclosure. For example, features of the illustrative embodiments can be combined, separated, interchanged, and/or rearranged to generate other embodiments. Such modifications and variations are intended to be included within the scope of the present disclosure.
Turning now to the drawings, FIG. 1 depicts a mouth portion of a reclosable package 10 with an agent structure 50 containing an active agent. The agent structure 50 is located below a reclosable closure arrangement such as a fastener or zipper 14. FIG. 2 shows the reclosable package 10 with the mouth portion depicted in FIG. 1 in a partial open position.
Referring to FIGS. 1 and 2, the mouth portion of the reclosable package 10 includes a pair of first and second opposing body or wall panels 16, 18 that make up a package body 20 and define an interior space 22. Connected to the first body panel 16 is a first track 24 having a first profile 26 and a first fin portion 28 extending generally downward from the first profile 26. The first body panel 16 has an outer surface 16 a and an inner surface 16 b. Connected to the second body panel 18 is a second track 30 having a second profile 32 and a second fin portion 34 extending generally downward from the second profile 32. The second body panel 18 has an outer surface 18 a and an inner surface 18 b. The inner surface 16 b is attached to the first fin portion 28. The inner surface 18 b is attached to the second fin portion 34. It is contemplated that one or more of the fin portions can be attached to the outer surfaces 16 a, 18 a.
The first and second profiles 26, 32 are releasably engageable with each other to provide a reclosable seal to the package 10. An optional breakable element 12 that initially extends from the first fin portion 28 to the second fin portion 34 can be used. The breakable element 12 of FIG. 1 is depicted with an optional one-time breakable preferential area of weakness or preferential tear area 38 to form a one-time breakable tamper evident feature. It is not necessary that the breakable element 12 have the one-time breakable preferential area of weakness 38. For example, in some embodiments, the breakable element 12 includes a resealable adhesive or cohesive seal. The one-time breakable preferential area of weakness 38 can be a score line, a series of perforations, or a highly oriented region. Additionally, the preferential area of weakness 38 can be made in a manner to separate by cutting therethrough. The preferential area of weakness 38 inhibits tampering with the reclosable package 10 prior to being opened.
The reclosable package 10 can further include an optional slider mechanism 36 (FIG. 2) slidably mounted to the fastener 14 for movement between a closed position and an open position. Referring to FIGS. 1 and 2, the first and second profiles 26, 32 are engaged to each other while the slider mechanism 36 is in the closed position, and movement of the slider mechanism 36 from the closed position to the open position disengages the profiles 26, 32 from each other.
The package 10 of FIG. 2 also includes end terminations 37. End terminations can have various purposes such as (a) preventing or inhibiting the slider mechanism 36 from going past the ends of the fastener 14, (b) interacting with the slider 36 to give a tactile indication of being closed, (c) assisting in inhibiting or preventing leakage from the package 10, and (d) holding the first and second profiles 26, 32 together and providing additional strength in resisting stresses applied to the profiles 26, 32 during normal use of the package 10. Further details concerning the construction and operation of the slider mechanism 36 and the end terminations 37 can be obtained from U.S. Pat. No. 5,067,208 to Herrington, Jr. et al., which is incorporated herein by reference in its entirety.
It is contemplated that other end terminations can be used instead of the above-described end terminations 37. For example, an end weld can be formed by heated bars pressed against the end of the fastener, ultrasonic welding, or other ways known in the art.
As illustrated in FIGS. 1 and 2, the reclosable package 10 of the present invention is opened by having a consumer grip the slider mechanism 36 and move it such that the first and second profiles 26, 32 of the respective first and second tracks 24, 30 are detached from each other. Next, the consumer tears open the breakable element 12 (if present) along the preferential area of weakness 38. Alternatively, the consumer may open the breakable element 12, if used, by cutting therethrough. The package can be resealed utilizing the fastener 14 and slider mechanism 36. Specifically, the consumer grips the slider mechanism 36 and moves it from the open position to the closed position so as to engage the complementary first and second profiles 26, 32.
A one-time breakable element 12 not only provides a consumer with the assurance that a newly purchased package has not been opened before, but also provides a good initial seal that preserves the freshness of the perishable contents of the package prior to its initial opening and can inhibit or prevent the active agent from being activated by an activation-triggering condition, such as moisture. Since the reclosable closure arrangements of FIG. 1 are located above the one-time breakable element, (i.e., the reclosable closure arrangement is further from the interior space), the operation of the reclosable closure arrangement is not hampered by the presence of the one-time breakable element.
Connected to the first body panel inner surface 16 b is the agent structure 50 that contains at least one active agent as schematically depicted in FIG. 1. The active agent can include a substance known to provide a desired function or effect on a package or contents thereof. In some embodiments, the active agent includes a freshness-extension agent, which functions to extend the life or freshness of food products or other perishables disposed in the package. In other embodiments, the active agent includes an odor management agent, which functions to mask, neutralize, and/or reduce an undesirable odor or to produce an aromatic odor in the package.
The agent structure 50 can be provided in a form and structure suitable for the desired effect of the agent and the structure of the package. For example, in some embodiments, the agent structure 50 can be in the form of a coating, a patch, a tape, a pouch, a combination thereof, or in any other form that can be incorporated or integrated into the structure of the package 10. The selection of a coating, patch, or pouch, or tape is often dependent on the type of active agent being used. For example, an active agent in a powder form (e.g., minerals containing chemistry) can be placed in an air-permeable pouch, rather than a patch because it is often difficult to embed powders in a patch. Alternatively, an active agent in a powder form can be dusted onto a component of the package, such as a body panel. Non-limiting examples of powdery active agents that can be incorporated into the agent structure 50 include perlite, calcium carbonate, kaolin, and ASEPTROL® antimicrobial manufactured by Engelhard.
If a tape or patch is used as or to support the agent structure 50, the tape or patch can include an adhesive, a patch-like component, and/or a release system such as a slip additive which assists in inhibiting or preventing the agent structure from sticking to the adhesive. For example, the release system can be located on a surface of the tape or patch that is located distally from the surface that contacts the body panel to which the tape or patch is to be attached, so that sticking is inhibited or prevented when the package is wound into a roll. Materials such as siloxane and glycerol monostearate can be among the components of such a release system.
In accordance with another aspect of the present invention, the active agent can be extruded with the body panel 16. For example, the active agent can be blended into the body panel material in oil or powder form, or can be distributed in the form of microcapsules in the material of the body panel 16. In a preferred embodiment, the active agent is microencapsulated prior to being integrated into the package structure. Microencapsulation encloses the active agent within a polymeric material that can withstand heat during package processing and manufacturing, but which degrades, dissolves, or otherwise breaks open and releases the active agent upon contact with pre-determined environmental factors such as moisture. The active agent can be encapsulated into microcapsules, and the microcapsules can be interspersed with the molten material of the body panel and extruded into body panel 16 during bulk production.
The body panel 16 can be otherwise impregnated with the active agent. It is also contemplated that the active agent can be sprayed, brushed, coated, laminated, stamped, or otherwise applied onto the body panel 16.
In some embodiments, the active agent includes one or more freshness-extension agents. The freshness-extension agent can be, for example, a natural oil, an anti-microbial, a modified atmosphere, or another substance that can extend the freshness or shelf life of food products or other perishables. For example, some non-limiting examples of freshness-extension ingredients include isothiocyanate such as allyl isothiocyanate (AIT) from natural sources, d-limonene, eugenol, allicin, isothymol, thymol, chlorine dioxide, hydrogen peroxide, sodium percarbonate, ascorbic acid, citric acid, cinnamic aldehyde, mustard, cinnamon, peppermint, spearmint, triclosan, Chinese chive (Allium tuberosum), cinnamon (Cinnamomum cassia), corni fructus (Cornus officinalis), allyl cyanide, 1-cyano-2,3-epithiopropane, allyl thiocyanate, Lactobacillus reuteri, methyl isothiocyanate, cinnamon bark oil, lemon grass oil, thyme oil, methyl jasmonate, tea tree oil, ethyl alcohol, Salicylaldehyde, carvacrol, cymene, essential oil extracts of various onions, essential oil extract of garlic, berry phenolic extracts from cranberry, cloudberry, raspberry, strawberry, and bilberry, ellagitannins from cranberry, cloudberry, raspberry, strawberry, and bilberry, essential oils from nutmeg, mint, clove, oregano, cinnamon, sassafras, sage, thyme and rosemary, vanillin, vanillyl alcohol, vanillic acid, diacetyl, natural honey, fluorine dioxide, carbon dioxide, modified atmospheres and combinations thereof. The modified atmosphere can include nitrogen, oxygen, sulfur dioxide, carbon monoxide, carbon dioxide and combination thereof.
AIT, which can be naturally obtained from plants or perishables such as mustard and wasabi, is particularly advantageous as a freshness-extension agent for its anti-microbial properties. Preferably, the AIT is produced from plants such as mustard, which contains glucosinolate and myrosinase enzyme. Myrosinase and glucosinolate react with each other to produce AIT and, because the reaction involves hydrolysis, humidity activates AIT production. AIT has been shown to exhibit anti-bacterial and anti-microbial properties and, as it is released in a gaseous form throughout the package atmosphere, it enhances the atmosphere so as to inhibit bacterial growth and therefore extend perishable freshness. Hence, AIT-producing products, including wasabi, horseradish and mustard in various forms, such as extract, powder, oil, or ground seed, can be used as the freshness-extension agent in embodiments of the present invention.
In some embodiments, an AIT-containing freshness-extension agent can also be used in combination with another functional agent. For example, in one such embodiment, AIT is combined with an acid, which greatly enhances the production of AIT from mustard and, thus, the anti-microbial effect of mustard. Thus, if ground mustard seed is used as the freshness-extension agent, it can be combined in a desired ratio with anhydrous acid such as anhydrous citric acid for increased AIT production and, thus, enhanced freshness-extension function.
In accordance with another aspect of the invention, a functional agent can be provided in conjunction with the active agent to indicate the useful life of the active agent. For example, a color agent, or a color indicator, can be provided for visually indicating the useful life, residual amount, or release status of the active agent. Such color indicator provides a simple way to detect the release or consumption of the active agent such that the consumer can determine if any active agent remains. Thus, the color indicator minimizes the waste that might be caused by discarding the structure 50 prematurely before complete release of the active agent. This allows for a more effective use of the structure 50 by informing the consumer of the need for replacement.
Color change of the color indicator can be effected to e.g., correspond with the release of the active agent or amount of humidity in the package atmosphere, such as by moisture released by perishables contained in the package. For example, a “matched release” can be accomplished entrapping a color agent in microspheres or beads that are configured to degrade at a timed rate similar or matched with the rate of release of the active agent under similar environmental conditions.
The color indicator can gradually change color over time as the agent is released into the package atmosphere and the amount of residual agent is reduced, thus providing a “matched release,” corresponding to the release of the active agent. For example, a color indicator that initially shows yellow color can gradually change, corresponding to release of the agent, to a clear colorless state. Such color indicator also indicates the extent or amount of the residual agent by gradually changing or fading the tone or shadow of color over time.
Any dye material or a material that can provide “matched release” can be used. For example, a food-grade methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), or carboxy methyl cellulose (CMC) can be used. These materials dissolve in moisture, and can be provided such that the material dissolves at substantially the same rate as the life of the agent. Any commercially available food-grade MC, HPMC, or CMC can be used, e.g., Walocel® HM HPMC, Dow METHOCEL®, and Hercules Aqualong and Benecel®.
In one embodiment, the structure contains MC which has a different color from that of the structure. For example, MC having a blue color is contained in a structure having a green color. As the agent is released and MC dissolves in moisture, the color of the structure changes from blue to green, showing expiration of the agent.
The color indicator can also incorporate the technology disclosed in U.S. Pat. No. 6,124,219 to Fujita et al. and U.S. Patent Application Publication No. US 2005/0129937, the entire content of each of which is incorporated herein by reference thereto. For example, U.S. Pat. No. 6,124,219 discloses a functional material which fades in color with the volatilization of a volatile agent. According to this patent, the volatile agent and an oil-soluble dye, which has a dissolving proportion of 0.0001 to 1%, are retained in the pores of a porous carrier undyeable with the oil-soluble dye. The dye is dissolved in, and colors, the volatile agent, and the change in color of the functional material is therefore disclosed to be closely related to the dissolving proportion of the oil-soluble dye. Since the carrier has no affinity for the dye, the dye separates on the surface of the carrier when the volatile agent is volatilized nearly completely, and the functional material manifests the color of the carrier itself. Any suitable natural or synthetic dye, ink or coloring that is compatible with the active agent, i.e. one that does not adversely react with the active agent, can be used.
When disposed in the form of a separate agent structure, a base layer also is provided. The base layer can be made of a diffusion material with the active agent contained therein, and/or can have the active agent disposed between the base layer and the removable covers. Alternatively or additionally, a diffusion layer can be disposed between the base layer and the removable covers and/or a barrier layer can be provided on the base layer opposite the removable covers. The barrier layer, base layer and diffusion layers preferably are made of polypropylene, polyethylene, and ethylmethyl acrylate, respectively.
The separate agent structure can be in the form of a patch, a tape or a pouch. By providing an adhesive, the structures can be adhered to a body panel of the package, or can simply be placed within the package. If attached to a wall or body panel of a package, such attachment can be facilitated by an adhesive, cohesive, fusion or weld connection
Alternatively, or additionally, the color indicator can function as an “agent marker” that detects and indicates the existence of the agent in the package atmosphere. For example, a color indicator can have a yellow color when no active agent is detected, e.g., before activation of the active agent or after the active agent is depleted, and can display green color when the active agent detected.
The color indicator can be designed to indicate food spoilage or contamination, or presence of a particular gas, compound, or odor in the package atmosphere, in addition to the life or presence of the active agent. Such an indicator or detector is disclosed in U.S. Pat. Nos. 6,325,974; 5,306,466; 6,841,392; 6,576,474; 6,495,368; 6,361,962, and 5,439,648 and U.S. Patent Application Publication Nos. US 2004/0142495 and US 2005/0112085, the entire content of each of which is incorporated herein by reference thereto.
For example, U.S. Pat. No. 6,325,974 discloses a package for decayable foodstuffs having an indicator, which can change color when exposed to an atmospheric gas and/or a volatile compound produced as a result of decay of the foodstuff contained in the package. U.S. Pat. No. 5,439,648 also discloses a gas indicator for a modified atmosphere packaging. The indicator is adapted to change color at different predetermined ratios of gases contained in the package, and changes color if the package is tampered with and a gas enters into or escapes from the package.
U.S. Pat. No. 5,306,466 discloses a food contamination detector in the form of a bar code. The bar code contains an antigenic determinant (antibody) of toxins or contaminants irreversibly bound to a transparent membrane. The antibody is further labeled with a colored latex bead such that, when toxins from food come in contact with the bar code and bind to the antibody, the color develops on the bar code. Instead of antibodies, a chemical indicator can be utilized. U.S. Patent Application Publication No. US 2004/0142495 discloses a similar method for detecting the presence or absence of an analyte with antibodies. U.S. Pat. No. 6,841,392 discloses use of multiple antibodies to detect biological materials that have reached a predetermined concentration or threshold level. Specific polymers can be incorporated such that binding of a biological material induces a molecular change in the polymer, resulting in a distinctly colored icon on the packaging material.
Instead of antibodies, metal complexes can be used to detect food spoilage, as disclosed in U.S. Pat. No. 6,593,142 and International Publication No. WO 00/13009, the entire content of each of which is herein incorporated by reference thereto. For example, a metal complex that selectively binds biogenic amines or sulfur compounds can be used.
The indicator can change color or emit fluorescence based on a pH change or the presence of compounds resulting from microbial spoilage, including amines, carboxylic acids, and aldehydes, as disclosed in U.S. Pat. Nos. 6,576,474 and 6,495,368.
The indicator can be odor-sensitive, as disclosed in U.S. Patent Application Publication No. US 2005/0112085, and can indicate, among others, garbage odor, raw meat odor, common household odors, cooking odors, mercaptans, amines, ammonia, sulfur, sulfides, and certain acids.
The color indicator can be disposed in the package in the same manner as, or even with, the active agent. For example, the color indicator can be disposed in the form of a coating, patch, pouch, or tape that is attached to a component of the package; extruded with a component of the package; sprayed, brushed, coated, laminated, or stamped onto a component of the package; impregnated into a component of the package; and/or distributed in the material of a component of the package, such as in the form of microcapsules.
The color indicator can be disposed on the same patch that includes the active agent, or can be disposed separate from the patch. When the active agent and color indicator are provided on the same patch, each can have a placement that is separate from, or overlap with, the placement of the other. For example, the color indicator can be sprayed, brushed, coated, laminated, or stamped on a surface of the patch overlapping the placement of the active agent, or impregnated into or distributed in the material of the patch together with the active agent.
When disposed in the form of a separate agent structure, base layer also is provided. The base layer can be made of a diffusion material with the active agent contained therein, and/or can have the active agent disposed between the base layer and the removable covers. Alternatively or additionally, a diffusion layer can be disposed between the base layer and the removable covers and/or a barrier layer can be provided on the base layer opposite the removable covers. The barrier layer, base layer and diffusion layers preferably are made of polypropylene, polyethylene, and ethylmethyl acrylate, respectively. Alternatively, and additionally, the indication can be in the form of a scent or any other means detectable to the user.
The freshness-extension agent can also provide other enhancement functions, and therefore can be used for such other purposes. In some embodiments, the freshness-extension agent can include a freshness component for extending food freshness and an odor component for masking, reducing, and/or neutralizing only a pungent odor of the freshness component, but not other odors of the contents stored in a package. Preferably, the odor component does not mask the odors of the contents stored in the package, such as food odors or food spoilage odors, so that decay or spoilage of the contents can be detected by smell. For example, a freshness-extension agent including an AIT freshness component can also include a fragrant component, such as vanilla, cinnamon, or citrus oil, which can mask the pungent odor of AIT, but not mask or otherwise affect the odor of the stored contents. Preferably, the freshness-extension agent does not impart its own organoleptic properties to the stored contents, and thus permits a user to readily detect decay or spoilage of stored contents by smell.
Alternatively, in some embodiments, the agent structure 50 includes one or more odor management agents. Advantageously, the odor management agent can be incorporated into packages configured for collecting garbage or waste to mask, neutralize, and/or reduce undesirable odors. Alternatively, the odor management agent can be used to provide or create an odor to a package. An odor management agent can thus be incorporated into thermoplastic bags or liners and other containers, such as garbage or waste bags, diaper containers, laundry bags, storage bags, and disposable medical bags or containers.
Non-limiting examples of odor management agents include AIT, d-limonene, mustard, natural oils, chlorine dioxide, hydrogen sulfide, methyl mercaptan, ammonia, citronella, pine, flowery, and substituted esters such as METAZENE®.
A preferred embodiment of an odor management agent includes AIT, which agent can be provided by incorporating, for example, mustard in the agent structure 50. Mustard, whether in the form of ground mustard seed, powder, oil, or paste, can be provided alone or in combination with an acid (such as citric acid) to catalyze the production of AIT from mustard and enhance the anti-microbial and odor management properties of the mustard. Because of its effectiveness in extending perishable freshness as previously described herein, AIT can provide multiple functions when incorporated into a perishable package, e.g., AIT can perform both freshness-extension and odor-management functions.
In some embodiments, the odor management agent can include an additional ingredient for providing a pleasant or desired odor or scent to a user. For example, a natural oil such as lemon grass oil can be used to manage odors emanating from a package, to mask the odor of the primary odor management agent itself, or to make the odor of the odor management more pleasant to a user. It has been shown that a composition comprising ground mustard seed and anhydrous citric acid mixed with about 5% by weight of lemon grass oil is particularly effective at managing unpleasant odors.
If an agent structure 50 includes an aromatic or perfumery ingredient for providing a desired scent to a package, an additional material for enhancing scent concentration in the interior of the package can be included. For example, the agent structure 50 can include perlite to increase the scent concentration. Perlite is desirable for use because of its ability to retain scent, its stability, and its surface area. Non-limiting examples of other materials for enhancing scent include microspheres, talc, silicon, silicate such as aluminum silicate, vermiculite, diatomaceous earth, or combinations thereof.
Further in accordance with the invention, the agent structure 50 can be provided with an activation system that is triggered when the reclosable package is opened or filled with contents. The activation system can be mechanical in nature, such as a perforation or a peel apart system that once separated initiates the release of the active agent. Another activation method can be based on the humidity or moisture level that is present in the package (e.g., which correlates to water activity of the contents). For example, a high amount of humidity can initiate a chemical or other reaction that subsequently releases a volatile chemical such as carbon dioxide or chlorine dioxide. In such an example, a greater amount of active agent is added when the humidity is higher in the reclosable package. Examples of reactions that are activated by a high humidity level are salt and acid reactions, such as sodium bicarbonate and citric acid, or sodium hypochlorite and citric acid. The release of AIT is also aided by humidity as previously explained. In such examples, a greater amount of active agent is released into the package atmosphere when the humidity increases.
During a method of operation of a reclosable package with a humidity-activated freshness extension agent, for example, perishables are placed in the interior of the package, and the humidity or moisture level in the perishables activates the freshness-extension agent. Additionally, if the agent structure is disposed proximate the mouth of a bag-like package or proximate the rim of a container-like package, selective activation or release can be accomplished. For example, the humidity or moisture level of the perishables can activate the agent as the perishables travel in the vicinity of the agent (e.g., through the mouth or past the rim of the package during the initial placement of the perishable products into the interior), while the perishable products remain disposed in the interior, and upon entry of air into the interior (e.g., during an opening of the package). Disposing the agent structure proximate the mouth or rim of a package can also be advantageous when maximum display of the contents is desired in a transparent package.
A humidity activation method can further be controlled by providing a barrier layer material. For example, it is preferable that the body panels provide a barrier layer or be formed of a barrier material so as to create an enclosed environment to prevent or inhibit the introduction of humidity and/or the release of active agent when the package is closed.
As used herein, the terms “barrier layer” and “barrier material” include layers or materials that inhibit, the release of an active agent into a package atmosphere to the maximum extent possible. As such, containers utilizing active agent can be shipped and stored and don't require immediate use for effectiveness. That is, by preventing premature activation and/or release of active agent, sufficient active agent is available when the consumer desires to use the container.
An example of such a material is polyethylene glycol (PEG) incorporated into low density polyethylenes (LDPE). Other materials providing a barrier to transfer of water, water vapor, oxygen, nitrogen, carbon dioxide, ethylene, volatile or non-volatile active agents include but are not limited to polymers, copolymers, blends, extrusions, co-extrusions, coatings, metallization or laminations of: low density polyethylene (LDPE), linear low density polyethylene (LLDPE), linear medium-density polyethylene (LMDPE), high density polyethylene (HDPE), very low density polyethylene (VLDPE), metallocene (mPE), polypropylene (PP), oriented polypropylene (OPP), acrylonitrile butadiene styrene (ABS), acrylonitrile-styrene-acrylate (ASA), acrylonitrile-EPDM-styrene (AES), ASA/AES copolymers, polyamide 6, polyamide 66 and their copolyamides, poly vinyl chloride (PVC), acrylic, polybutylene terephthalate (PBT), ethylene/ethyl acrylate (EEA), ethylene/vinyl acetate (EVA), modified polystyrene, ethylene-vinyl alcohol (EVAL or EVOH), polyvinylidene chloride (PVDC), liquid crystal polymer (LCP), polyamides, polyacrylic acid (PAA), polylactic acid (PLA), polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG), saran, ceramic filled polymers, nanocomposite polymers, polychlorotrifluoroethylene (PCTFE), polymethyl methacrylate (PMMA), acrylonitrile-methyl acrylate (AC-MA), polyphenylene ether (PPE), polyphenylene oxide (PPO), thermoplastic elastomer, cellophane, nylon, modified polyolefins with barrier properties, cyclic olefin copolymers, polyacrylonitriles, acrylonitrile copolymers, polyacetals, modified polyesters, acrylic derivatives, and inorganic barrier coatings.
Preferred barrier materials include metal foil, polyethylene terephthalate (PET), metallized polymers, such as metallized polyester, polyvinylidene chloride (PVDC), and ethylene vinyl alcohol (EVOH). Preferred materials that are suitable for blocking the introduction of water vapor into a package include low density polyethylene (LDPE), linear low density polyethylene (LLDPE), linear medium-density polyethylene (LMDPE), high density polyethylene (HDPE), polypropylene (PP), oriented polypropylene (OPP), acrylonitrile-methyl-acrylate (AMA), poly vinyl chloride (PVC), PMMA, acrylic, ethylene/vinyl acetate (EVA), polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG), saran, ceramic filled polymers, nanocomposite polymers, polychlorotrifluoroethylene (PCTFE), polymethyl methacrylate (PMMA), acrylonitrile-methyl acrylate (AC-MA), modified polyolefins with barrier properties, cyclic olefin copolymers, polyacrylonitriles, acrylic derivatives, inorganic barrier coatings, foils and metallized polymers, polyvinylfluoride (PVF), ionomer, polyetherimide, Polyethylene naphthalate (PEN), Butyl rubber, and polychloroprene (Neoprene G).
Materials that are suitable for blocking the release of active agents and/or oxygen from a package include high density polyethylene (HDPE), polypropylene (PP), oriented polypropylene (OPP), acrylonitrile-methyl-acrylate (AMA), poly vinyl chloride (PVC), PMMA, acrylic, polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG), saran, ceramic filled polymers, nanocomposite polymers, polychlorotrifluoroethylene (PCTFE), polymethyl methacrylate (PMMA), acrylonitrile-methyl acrylate (AC-MA), modified polyolefins with barrier properties, cyclic olefin copolymers, polyacrylonitriles, acrylic derivatives, inorganic barrier coatings, foils and metallized polymers, Polyvinylfluoride (PVF), Polyetherimide, Polyethylene naphthalate (PEN), Polyvinylidene fluoride (PVDF), polyimide, polyetheretherketone (PEEK), polyoxymethylene (POMC), polyacetal, acrylonitrile butadiene styrene (ABS), polyamide 6, polyamide 66 and their copolyamides, polybutylene terephthalate (PBT), thermoplastic polyester (TPE), modified polystyrene, ethylene-vinyl alcohol (EVAL or EVOH), polyamides, polylactic acid (PLA), cellophane, nylon, modified polyesters, and polyethersulfone (PES).
Of the foregoing materials, those that are suitable as barrier layers for blocking both the introduction of water vapor to and the release of active agents from a package include high density polyethylene (HDPE), polypropylene (PP), oriented polypropylene (OPP), acrylonitrile-methyl-acrylate (AMA), poly vinyl chloride (PVC), PMMA, acrylic, polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG), saran, ceramic filled polymers, nanocomposite polymers, polychlorotrifluoroethylene (PCTFE), polymethyl methacrylate (PMMA), acrylonitrile-methyl acrylate (AC-MA), modified polyolefins with barrier properties, cyclic olefin copolymers, polyacrylonitriles, acrylic derivatives, inorganic barrier coatings, foils and metallized polymers, Polyvinylfluoride (PVF), Polyetherimide, and Polyethylene naphthalate (PEN).
It is also contemplated that other barrier materials such as foils and metallized polymers such as metallized oriented polypropylenes (OPP) can be used. The barrier layer is substantially impermeable to at least water vapor and active agents, and, in some embodiments, also to oxygen, nitrogen, and carbon dioxide, or combinations thereof. The barrier layer thus inhibits or prevents water vapor (and, in some embodiments, oxygen, nitrogen, and carbon dioxide) from entering the interior of the package, while inhibiting or preventing the active agent from escaping the interior of the package. An example of a cyclic olefin copolymer that can be used in forming the barrier layer is TOPAS® 8007. Useful cyclic olefin copolymers are believed to be available from several companies. For example, Ticona, a business of Celanese AG, in Summit N.J. has cyclic olefin copolymers available. Other companies that are believed to have cyclic olefin copolymers available include Nippon Zeon (Japan), Mitsui Chemical (Japan) and JSR (Japan), formerly know as Japan Synthetic Rubber. Ticona, a business of Celanese AG, has commercially available cyclic olefin copolymers (COCs) under the designation TOPAS®. These cyclic olefin copolymers are believed to be prepared with feedstocks of norbornene and ethylene and the use of a metallocene catalyst. There are believed to be at least four grades of TOPAS® resins available (TOPAS® 8007, TOPAS® 6013, TOPAS® 6015 and TOPAS® 6017). The four grades of TOPAS® resins available have glass transition temperatures, T_g, of 80, 140, 160 and 180° C., respectively. The corresponding norbornene levels of the four grades of TOPAS® resins are 35, 48, 55 and 59 mole %.
The agent structure 50 can be made of polymeric materials including thermoplastic materials. Alternatively, if formed as part of the package, a polymeric matrix layer can be provided for impregnating or supporting a microencapsulated active agent into a component of the package, e.g., a body panel. The matrix layer of the agent structure 50 can be made of polyolefinic materials such as polyethylenes, polypropylenes, polystyrenes, and combinations thereof. Non-limiting examples of the matrix layer materials include polymers, copolymers or blends of: low density polyethylene (LDPE), linear low density polyethylene (LLDPE), linear medium-density polyethylene (LMDPE), high density polyethylene (HDPE), very low density polyethylene (VLDPE), metallocene (mPE), polypropylene (PP), polyamide 6 polyamide 66 and their copolyamide, poly vinyl chloride (PVC), acrylic, thermoplastic polyester (TPE), ethylene/vinyl acetate (EVA), polystyrene (PS), high impact polystyrene (HIPS), modified polystyrene, liquid crystal polymer (LCP), polyamides, polyacrylic acid (PAA), polylactic acid (PLA), polyethylene terephthalate glycol (PETG), polymethyl methacrylate (PMMA), polyphenylene ether (PPE), thermoplastic elastomer, and cellulose and filled plastics. These materials generally provide a good barrier to water vapor, but allow permeation of oxygen and active agents. It may be desirable to have a patch, tape, or pouch that comprises polyethylene because of its recyclability. Another example of a material that can be used to form a patch, tape, or pouch structures is ethyl methyl acrylate (EMA). A surface of the patch, tape, or pouch can be formed of a porous non-woven material (e.g., gauze) that allows the active agent such as freshness extension or odor management agent to be released. For odor management, one of the layers of the odor management structure can further include a fragrance (e.g., a liquid fragrance), a scent-enhancing mineral, and/or a polymeric resin (e.g., LLDPE).
FIG. 25 illustrates a multi-layer base layer for an agent structure. In this embodiment, the base layer includes at least one layer of active agent (e.g., layer 2520) disposed between barrier layers and/or diffusion layers (e.g., layers 2510, 2530). For example, a polymer layer containing active agent can be sandwiched between two adjacent diffusion layers. The agent-containing layer is made of a polymer or a blend of polymers that are compatible with the active agent disposed therein, as previously described. The adjacent diffusion layers are made of a polymer or a blend of polymers that are permeable to the active agent. The outer layers function as physical barriers to the inner agent-containing layer, therefore preventing premature activation of the active agent during manufacturing process of the package. Thus, a multi-layer patch can be especially advantageous when manufacturing of the package involves processes, e.g. extrusion, or environments, e.g., high humidity, that may cause premature activation of the active agent prior to placement within a barrier environment. In addition to a single layer of active agent sandwiched between diffusion layers, additional barrier layers or diffusion layers can be included.
As will be understood by those of ordinary skill in the art, the amount of agent to be used in combination with a package will depend on the environment in which the agent is in use, e.g., the loss and release rates of the agent. The release rate refers to the rate at which the agent is released into the interior of the package, and the loss rate refers to the rate at which the released agent escapes from the interior of the package. Preferably, the agents of the present invention are disposed in amounts such that the release rate of the agent is greater than the loss rate of the agent during a pre-determined “shelf life” or duration of use, so that the presence of agent in the interior of a package is replenished faster than it is lost, thus ensuring effective performance of the agent. The loss rate of the agent depends upon a variety of factors related to package design, construction, and use.
It is contemplated that additional layers can be added to the coating, patch, pouch, or tape. For example, a barrier layer can be added to assist in keeping the freshness-extension agent in communication with the interior of the reclosable package and, thus, assist in preventing or inhibiting the freshness-extension agent from permeating through the body panel.
For example, and with reference to the package embodiment of FIG. 1, each of the opposing body panels 16, 18 forms a barrier layer that is substantially impermeable to at least water vapor and active agents and, in some embodiments, also to oxygen, nitrogen, carbon dioxide, or combinations thereof. The opposing body panels 16, 18 thus can include, i.e., be at least partially formed from one or more of, the foregoing materials. The opposing body panels 16, 18 can include barrier layers located on exterior and/or interior surfaces of the packages.
For purposes of illustration, the disclosed packages of the present invention will now be further described herein with respect to freshness-extension agents. Those of ordinary skill in the art will understand that the disclosed packages can be suitably modified to include other types of active agents.
In one such embodiment, the barrier layer can be located on an inner surface of a freshness-extension structure as shown in, for example, FIG. 3 a. In FIG. 3 a, one side of a package 210 is depicted with a body panel 212 that includes a freshness-extension structure 214, and a second body panel (not shown in FIG. 3 a). The freshness-extension agent of the freshness-extension structure 214 is in communication with the interior space, while one surface of the freshness-extension structure 214 is attached to a surface 212 a of the body panel 212 via an adhesive, a heat seal, or a weld, e.g., an ultrasonic weld. It is contemplated that other attachment methods can be used. For example, the freshness-extension structure can be attached to at least one surface of the body panels using mechanical methods such as clips or staples. Thus, the freshness-extension structure can be provided as a coextrusion structure or as a laminate. Alternatively, it can be coated on a layer of film.
One example depicted in FIG. 3 b includes a reclosable package 230 comprising a first body panel 212, a second body panel (not shown in FIG. 3 b), and a freshness-extension structure 234. The structure 234 comprises a first layer 216 that is a barrier layer and a second polymeric layer 218 that includes a freshness-extension agent. The first layer 216 can be a polymeric barrier layer using one of the previously mentioned barrier materials. One example of a polymer that can be used in the second polymeric layer 218 is a polyolefin such as a linear low density polyethylene (LLDPE). An outer surface 216 a of the first layer 216 of FIG. 3 b is attached to an inner surface 212 a of the first body panel 212. The second polymeric layer 218 is directly adjacent to the first layer 216 so that the freshness-extension agent is in communication with the interior space. Depending on the materials that form the first and second layers 216, 218, it may not be necessary to adhesively attach the layers together. Rather, for example, the first and second layers can be co-extruded together if the materials for forming the first and second layers are compatible.
It is also contemplated that information can be printed on the freshness-extension structure 234 such as on the barrier layer. It is contemplated that the printing can occur on different locations of the structure. For enhanced visibility and readability of the printing, it may be desirable to print on the surface of the freshness-extension structure that is closest to the body panel when the structure is located in the interior of the reclosable package. For example, in FIG. 3 b, the printing would be desirably located between the first body panel 212 and the first layer 216. If adhesive is used to attach the first layer 216 of FIG. 3 b to the surface 212 a, then the printing can be located between the adhesive and the first layer 216. It is contemplated that other attachment methods can be used such as a heat seal or mechanical methods.
Referring to FIG. 3 c, a reclosable package 250 comprises a first body panel 212, a second body panel (not shown in FIG. 3 c), and a freshness-extension structure 254 in the form of a patch or tape. It is contemplated that the structure can be in the form of a pouch or a coating. The freshness-extension structure 254 comprises a first layer 216 that is a barrier layer, and a second polymeric layer 218 that includes a freshness-extension agent, and a third polymeric layer 220 that is a diffusion layer. The first layer 216, as discussed above, can be a polymeric layer. The second polymeric layer 218 that includes the freshness-extension agent is located between the first and third layers 216, 220. One example of a polymer that can be used in the second polymeric layer 218 is a polyolefin, such as a linear low density polyethylene (LLDPE). The freshness-extension agent is in communication with the interior space of the reclosable package via the third polymeric layer 220 that is permeable. Thus, the third polymeric layer 220 controls the permeability and must be permeable to the extent that the freshness-extension agent can enter the interior of the reclosable package therethrough.
It is contemplated that the third polymeric layer 220 can comprise a cyclic olefin copolymer. The third polymer layer can comprise from about 10 to about 80 wt. % or, more specifically, from about 20 to about 40 wt. % cyclic olefin copolymer to assist in reducing curling of the polymeric structure. While not being bound by theory, curling tends to be caused when the materials forming the polymeric-structure layers are not as compatible with each other because of, for example, their different shrink rates. The barrier layer can comprise a more crystalline material that does not shrink much, if any, over time as compared to the diffusion layer that can comprise a material, such as polyethylene, that tends to shrink over time. The disadvantage of such structure curl is that the edges tend to curl in a transverse direction upon itself and therefore cause processing problems. The curling of the polymeric structure can be reduced or inhibited by using a cyclic olefin copolymer in the third polymeric layer, whereby the first layer and the third polymeric layer become more compatible. The addition of a cyclic olefin copolymer to the third polymeric layer 220 also slows the permeation of the freshness extension agent into the interior of the reclosable package 250.
As discussed above, it is contemplated that the freshness-extension structure 254 of FIG. 3 c can have a release agent (e.g., a slip additive) that assists in preventing or inhibiting the polymeric structure from sticking to itself. It is also contemplated that information can be printed on the structure 254. The first layer 216 can be attached to the surface of the body panel(s) via an adhesive, heat seal or other methods.
Referring to FIG. 3 d, a reclosable package 270 comprises a first body panel 212, a second body panel (not shown in FIG. 3 d), and a freshness-extension structure 274 in the form of a patch or tape. It is contemplated that the structure 274 can be a pouch. The freshness-extension structure 274 comprises a first layer 216 being a barrier layer, and a second polymeric layer 219 being a diffusion layer and including a freshness-extension agent. The freshness-extension agent must be able to communicate with the interior space of the reclosable package or bag. The first layer 216 can be attached to the body panel 212 via an adhesive, a heat seal, a weld, or other methods.
The reclosable package can include more than one freshness-extension structure that includes a freshness-extension agent therein. For example, the reclosable package can include two or three freshness-extension structures that each contain a freshness-extension agent.
A freshness-extension structure (e.g., a freshness-extension agent containing patch, tape, pouch, or coating) can vary in size and is dependent on factors such as the desired amount of freshness-extension, the particular freshness-extension agent being used, the number of freshness-extension structures being used in the reclosable package, and the size of the reclosable package. The dimensions of the freshness-extension structure are generally from about ½ inch or 1 inch to about 12 inches. Non-limiting examples of freshness-extension structure dimensions include ½ inch×1 inch, 1 inch by 1 inch, ½ inch×2 inches, 1 inch×6 inches, 2×4 inches, and 4×12 inches. The thicknesses of the freshness-extension structures can vary in the present invention but are generally less than about 20 mils, preferably from about 12 to 16 mils, and more preferably from about 14 to 15 mils.
According to another embodiment, the freshness-extension structure of the reclosable package is delivered in a non-woven matrix. The non-woven matrix can be impregnated after the non-woven matrix has been formed. The impregnation of the non-woven matrix can be accomplished by a freshness-extension agent coating. Alternatively, the non-woven matrix can be initially formed with the freshness-extension agent therein. According to a further embodiment, the freshness-extension agent of the reclosable package can be micro-encapsulated in a freshness-extension structure.
The freshness-extension structure being a patch, tape, pouch, or coating in one embodiment is located in the interior of a reclosable package or bag, such as the reclosable package 10. For example in FIG. 3 a, a partial cross-sectional view of one side of the reclosable package 210 is depicted with the body panel 212 and the freshness-extension structure 214. The structure 214 is attached to an interior surface 212 a of the body panel 212 in which the interior surface 212 a forms an interior portion of the reclosable package 210.
Alternatively, the freshness-extension structure being a coating, patch, pouch, or tape can be located on an exterior surface of an article or within layers of an article such that the freshness-extension agent is able to permeate into or communicate with the interior of the reclosable package. For example, the freshness-extension structure being a coating, patch, pouch, or tape can be located on an exterior surface of a reclosable package in which a portion of the body panel is removed such that the freshness-extension agent from the freshness-extension structure can permeate into the interior of the reclosable package. For example, referring to FIG. 4, a partial cross-sectional view of one side of a reclosable package 310 is shown with a freshness-extension structure 314 attached to an exterior surface 316 a of a body panel 316. The body panel 316 has at least one opening 318 that allows the freshness-extension agent from the freshness-extension structure 314 to permeate into the interior of the reclosable package 310. The opening(s) 318 can be one large opening or a plurality of smaller openings that extends from and through the body panel 316 of the reclosable package 310. The opening(s) 318 can be formed by processes known in the art including a perforation process.
In another example, FIG. 5 depicts a partial cross-sectional view of one side of a reclosable package or bag 410. The reclosable package or bag 410 comprises an exterior layer 412, a freshness-extension structure 414, and an interior layer 416 with opening(s) 418. The freshness-extension structure 414 is located between and attached to the exterior layer 412 and the interior layer 416. The opening(s) 418 allows the freshness-extension agent from the structure 414 to be in communication with the interior of the reclosable package or bag 410.
It is contemplated that a layer of a reclosable package can be permeable to the freshness-extension agent of the freshness-extension structure such that the freshness-extension agent is in communication with the interior of the reclosable package. FIG. 6 depicts such an example where a partial cross-sectional view of a reclosable package 510 is shown. The reclosable package 510 comprises a freshness-extension structure 514 and a diffusion layer 516. The diffusion layer 516 allows the freshness-extension agent from the freshness-extension structure 514 to enter the interior of the reclosable package.
The diffusion layer 516 can be made of a suitable material that allows the freshness-extension agent to reach the interior of the reclosable package in a relatively quick fashion. Thus, materials providing permeation of water, water vapor, oxygen, nitrogen, carbon dioxide, ethylene, volatile actives or nonvolatile active agents can be used for the diffusion layer. Examples of a diffusion layer 516 include polymers, copolymers, blends, extrusions, co-extrusions, coatings or laminations of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE), metallocene (mPE), polypropylene (PP), acrylonitrile butadiene styrene (ABS), polyamide 6, polyamide 66 and their copolyamides, poly vinyl chloride (PVC), acrylic, polybutylene terephthalate (PBT), thermoplastic polyester (TPE), ethylene/ethyl acrylate (EEA), ethylene/vinyl acetate (EVA), polystyrene (PS), high impact polystyrene (HIPS), modified polystyrene, ethylene-vinyl alcohol (EVAL or EVOH), polyacrylic acid (PAA), polylactic acid (PLA), filled polymers, hydrophilic nanocomposite polymers, polymethyl methacrylate (PMMA), thermoplastic elastomers, polydimethylsiloxane (PDMS), polymethylpentene (PMP), polyvinyl acetate (PVA), polyvinyl alcohol (PVAL), and cellulose acetate (CA), all of which have general affinity for moisture.
As will be understood by those of ordinary skill in the art, the same type of polymer material can be used in forming either the matrix, barrier, or diffusion layer, depending on the percentage ratio of the material in the layer composition, the quantity of the material in the layer composition (e.g., the thickness of the layer composition), and/or the method of fabrication. Thus, the use of a particular polymer material as a component for the matrix, barrier, or diffusion layer depends on its amount and manner of use.
FIG. 7 depicts another embodiment with a partial cross-sectional view of one side of a reclosable package 530 that includes an additional layer (exterior layer 512) as compared to the reclosable package 510 of FIG. 6.
It is contemplated that additional layers can be added in forming the reclosable packages shown in FIGS. 3-7. For example, an ethylene vinyl alcohol (EVOH) copolymer or polyvinylidene chloride layer (PVDC) can be used in forming the body panels of the reclosable package, or in forming a barrier layer of the package. Such a barrier layer assists in keeping the freshness extension ingredient in communication with the interior of the reclosable package. Other layers, such as a freshness-extension enhancing layer, are also contemplated. A freshness-extension enhancing layer can operate to enhance delivery of the freshness extension agent with increasing humidity. Such a freshness-extension enhancing layer is particularly advantageous, since increased humidity often results in a corresponding increase in bacterial growth that leads to increased perishable spoiling. One example of a freshness extension enhancing layer is polyvinyl alcohol (PVOH).
The freshness-extension structure 214 can include a peelable cover. An example of such an embodiment is depicted in FIG. 8 where a partial cross-sectional view of one side of a reclosable package 610 comprises a body panel 612, a freshness-extension structure 614, and a peelable cover 622. The peelable cover 622 covers at least a portion of the freshness-extension structure 614 and may cover the entire freshness-extension structure 614 that is exposed in the interior of the reclosable package 610. The peelable cover 622 prevents or inhibits the freshness-extension agent from escaping the freshness-extension structure 614 in its initial position shown in FIG. 8. The peelable cover can be attached to the body panel 612 and/or the freshness-extension structure 614. The peelable cover 622 is removed by a user from the freshness-extension structure 614 to enhance or begin the release of the freshness-extension agent from the freshness-extension structure 614. Typically, the removal of the peelable cover 622 by the user occurs when a package is going to have perishable placed into it. One example of the peelable cover 622 is a barrier layer such as EVOH or PVDC. It is contemplated that a peelable cover can be used with any of the freshness-extension structures that are in the form of a patch, tape, or pouch.
According to one embodiment, a reclosable package is adapted to store items and comprises a first thermoplastic body panel, a second thermoplastic body panel, and at least one polymeric freshness-extension structure adapted to extend the freshness of items by increasing the time items can be stored in the article without spoiling. The first and second body panels are joined along a pair of opposing sides and a bottom bridging the sides so as to form an open mouth. The joined first and second body panels form an interior space for storing items. The polymeric freshness-extension structure is attached to a surface of one or more the first and second body panels and is in communication with the interior space. The freshness-extension structure further includes a peelable cover in which the peelable cover is adapted to initially cover at least a portion of the polymeric freshness-extension structure.
According to another embodiment, a reclosable package can be used that includes two freshness-extension structures. For example, referring to FIG. 9 a, a reclosable package 710 comprises a first thermoplastic body panel 712, a second thermoplastic body panel (not shown in FIG. 9 a) a first freshness-extension structure 714 a, and a second freshness-extension structure 714 b. As discussed above, the first and second body panels are joined along a pair of opposing sides and a bottom bridging the sides so as to form an open mouth. The joined first and second body panels form an interior space for storing items.
The first freshness-extension structure 714 a comprises two layers and is a patch or tape. It is contemplated that the first and second freshness-extension structures can form a pouch. The first freshness-extension structure 714 a comprises a first layer 716 a being a barrier layer, and a second polymeric layer 719 a being a diffusion layer and including a freshness-extension agent. The first layer 716 a can be a polymeric layer. The second polymeric layer 719 a is directly adjacent to the first layer 716 a. The first layer 716 a is shown in FIG. 9 a as being attached to the first body panel 712 via an adhesive, heat seal or other methods.
Similarly, the second freshness-extension structure 714 b comprises two layers and is a patch or tape. The second freshness-extension structure 714 b comprises a third layer 716 b being a barrier layer, and a fourth polymeric layer 719 b being a diffusion layer and including a freshness-extension agent. The fourth polymeric layer 719 b is directly adjacent to the third layer 716 b. The third layer 716 b can be a polymeric layer. The second polymeric layer 719 a is releasably heat sealed at selected locations to the fourth polymeric layer 719 b such that the respective freshness-extension agent permeates into the interior of the reclosable package 710 via interior area 717.
The interior area 717 can be formed by having the first and second freshness-extension structures 714 a, b curl with respect to each other. As shown in FIG. 9 a, the interior area 717 is formed between the second and fourth polymeric layers 719 a, b. A slight curl of the freshness-extension structures enables the freshness-extension agent to be in communication with the interior of the reclosable package. It is desirable to have some curl in the embodiment depicted in FIG. 9 a to assist in enabling the freshness-extension agent to be in communication with the interior of the reclosable package or bag. As discussed above, the curling of the freshness-extension structures can be formed from using materials for forming the freshness-extension structures that are less compatible (i.e., the shrink rates of the materials differ).
It is contemplated that additional layers can be used in forming the two freshness-extension structures. For example, in FIG. 9 b, a reclosable package 730 comprises a first thermoplastic body panel 712, a second thermoplastic body panel (not shown in FIG. 9 b), a first freshness-extension structure 734 a, and a second freshness-extension structure 734 b. The first and second body panels are joined along a pair of opposing sides and a bottom bridging the sides so as to form an open mouth. The joined first and second body panels form an interior space for storing items.
The first freshness-extension structure 734 a comprises three layers and is a patch or tape. It is contemplated that the first and second freshness-extension structures can form a pouch or a coating. The first freshness-extension structure 734 a comprises a first layer 716 a being a barrier layer, a second polymeric layer 718 a comprising a freshness-extension agent, and a third polymeric 720 a being a diffusion layer. The first layer 716 a can be a polymeric layer. The second polymeric layer 718 a is located between the first and third layers 716 a, 720 a. The first layer 716 a is shown in FIG. 9 b as being attached to the first body panel 712 via an adhesive or heat seal such that the freshness-extension agent is in communication with the interior space. It is contemplated that other attaching methods can be used such as mechanical devices like clips or staples.
Similarly, the second freshness-extension structure 734 b comprises three layers and is a patch or tape. The second thermoplastic freshness-extension structure 734 b comprises a fourth layer 716 b being a barrier layer, a fifth polymeric layer 718 b comprising a freshness-extension agent, and a sixth polymeric layer 720 b being a diffusion layer. The fourth layer 716 b can be a polymeric layer. The fifth polymeric layer 718 b is located between the fourth and sixth polymeric layers 716 b, 720 b. The third polymeric layer 720 a is heat sealed at selected locations to the sixth polymeric layer 720 b such that the respective freshness-extension agent of the second polymeric layer 718 a and the fifth polymeric layer 718 b is adapted to enter the interior space of the reclosable package between the third polymeric layer 720 a and the sixth polymeric layer 720 b.
As discussed above, an interior area 727 can be formed by having the first and second freshness-extension structures 734 a, b curl with respect to each other. As shown in FIG. 9 b, the interior area 727 is formed between the third and sixth polymeric layers 720 a, b.
According to another embodiment, a reclosable package 810 is shown in FIG. 10 a comprising a first thermoplastic body panel 812 a, a second thermoplastic body panel 812 b, a first freshness-extension structure 814 a, and a second freshness-extension structure 814 b. The first and second body panels 812 a, 812 b are joined along a pair of opposing sides and a bottom bridging the sides so as to form an open mouth. The joined first and second body panels form an interior space for storing items.
The first freshness-extension structure 814 a comprises two layers and is a patch or tape. It is contemplated that the first and second freshness-extension structures can be in the form of a pouch. The first freshness-extension structure 814 a comprises a first layer 816 a being a barrier layer, and a second polymeric layer 819 a being a diffusion layer and including a freshness-extension agent. The first layer 816 a can be a polymeric layer. The second polymeric layer 819 a is directly adjacent to the first layer 816 a. The first layer 816 a is shown in FIG. 10 a as being attached to the first body panel 812 a via an adhesive or heat seal. It is contemplated that other attachment methods may be used. To adhere to the first body panel 812 a, the first layer 816 a can include a coating that is not sticky or tacky at room temperature. Such a coating may become sticky, for example, at higher temperatures, or upon exposure to infrared radiation or heat.
Similarly, the second freshness-extension structure 814 b comprises two layers and is a patch or tape. The second freshness-extension structure 814 b comprises a third layer 816 b being a barrier layer, and a fourth polymeric layer 819 b being a diffusion layer and including a freshness-extension agent. The third layer 816 b can be a polymeric layer. The fourth polymeric layer 819 b is directly adjacent to the third layer 816 b. The third layer 816 b is shown in FIG. 10 a as being attached to the second body panel 812 b via an adhesive or heat seal. It is contemplated that other attachment methods may be used. To adhere to the second body panel 812 b, the third layer 816 b may include a coating that is not sticky or tacky at room temperature. Such a coating may become s sticky, for example, at higher temperatures, or upon exposure to infrared radiation or heat.
It is contemplated that the first freshness-extension structure and the second freshness-extension structure can be formed of different compositions. For example, the first structure can include a first freshness-extension agent, while the second structure may be a second freshness-extension agent. In forming such an embodiment, the first and second freshness-extension structures can, for example, be formed by extruding two different patches, tapes, pouches, or by applying two different coatings.
Alternatively, the reclosable package can be formed by other than two or more layer structures. For example, a barrier layer need not be provided if the body panels 812 are formed of a suitable material to define a barrier layer. Furthermore, as shown in FIG. 10 b, a reclosable package 830 includes a first freshness-extension structure 834 a that comprises a first layer 816 a that comprises a freshness-extension agent, and a second polymeric layer 818 a that is a diffusion layer. The reclosable package 830 also includes a second freshness-extension structure 834 b that comprises a third layer 816 b that comprises a freshness-extension agent, and a fourth polymeric layer 818 b that is a diffusion layer. It is contemplated that the first and second freshness-extension structures can be made of different compositions, such as being made of different freshness-extension agents or diffusion layers.
According to yet another embodiment, the reclosable package can be formed by three or more layers. For example, as shown in FIG. 10 c, a reclosable package 850 includes a first freshness-extension structure 854 a that comprises a first layer 816 a that is a barrier layer, a second polymeric layer 818 a that comprises a freshness-extension agent, and a third polymeric layer 820 a that is a diffusion layer. The reclosable package 850 includes a second freshness-extension structure 854 b that comprises a fourth layer 816 b that is a barrier layer, a fifth polymeric layer 818 b that comprises a freshness-extension agent, and a sixth polymeric layer 820 b that is a diffusion layer. The first and second freshness-extension structures 854 a, b are attached to first and second body panels 812 a, 812 b, respectively, via an adhesive or heat seal. It is contemplated that the first and second structures can be made of different compositions, such as being made of different barrier materials or freshness-extension agents.
As previously described, the freshness-extension agents of the present invention can contain an activation system that is triggered by a user opening a reclosable package or placing contents therein. In some embodiments, such as the embodiment shown and described with respect to FIG. 8, the activation system of the freshness-extension agents of the present invention is mechanical in nature. For example, in the embodiment of FIG. 8, the activation system includes a perforation or a peel-apart system which, once separated, initiates the release of the freshness-extension agent.
In accordance with another such aspect of the invention, a reclosable package 910 is shown in FIG. 11 a comprising a first thermoplastic body panel 912 a, a second thermoplastic body panel 912 b, and a freshness-extension structure 914 disposed therebetween. The first and second body panels 912 a, 912 b are joined along a pair of opposing sides and a bottom bridging the sides so as to form an open mouth. The joined first and second body panels form an interior space for storing items. The freshness-extension structure 914 can be in the form of a patch or tape as embodied herein, and comprises three layers. Particularly, the freshness-extension structure 914 depicted in FIG. 11 a comprises a first layer 916 a being a barrier layer, a second polymeric layer 919 being a frangible diffusion layer with a freshness-extension agent, and a third layer 916 b being a barrier layer.
As shown in FIG. 11 a, the second layer 919 is a one-time breakable element extending between the first barrier layer 916 a and the second barrier layer 916 b. The one-time breakable element of the second layer 919 therefore inhibits or prevents the freshness-extension agent from escaping into the package while in its initial position shown in FIG. 11 a.
The one-time breakable element 921 can include one or more polymeric resins and polyolefins, and can be used with any of the previously-described freshness-extension structures. Polyolefins used as one-time breakable element include, but are not limited to, polyethylenes, polypropylenes, and combinations thereof. Some non-limiting types of polyethylenes include low density polyethylenes (LDPE), linear low density polyethylenes (LLDPE), high density polyethylenes (HDPE), medium density polyethylenes (MDPE) and combinations thereof. Other non-limiting examples include plastomers, elastomers, ethylene vinyl acetates (EVA), ethyl methacrylates, polymethylpentene copolymers, polyisobutylenes, polyolefin ionomers, cyclic olefin copolymers (COCs), or combinations thereof, including with polyethylenes and/or polypropylenes.
The one-time breakable element of the second layer 919 can include a one-time breakable preferential area of weakness or preferential tear area similar to the preferential areas of weakness or tear areas previously described herein or a one-time breakable adhesive or cohesive seal. Alternatively, the second layer 919 can be formed by selectively cross-linking the diffusion material to define the one-time breakable element. Generally, the bond between the second layer 919 and the adjacent layers must be stronger than the frangible portion of the one-time breakable element that joins portions 919 a and 919 b as described further below.
As shown in FIG. 11 b, breakage of the one-time breakable element divides the second layer 919 into a first portion 919 a and a second portion 919 b, each having a surface exposed, and thereby begins or enhances the release of freshness-extension agent thereto. Typically, breakage of the one-time breakable element by a user occurs when the package is initially opened to place contents therein.
In another such embodiment having a mechanical release mechanism, a reclosable package 1010 is shown in FIG. 12 a comprising a first thermoplastic body panel 1012 a, a second thermoplastic body panel 1012 b, a freshness-extension structure 1014, and a removable or peelable cover 1021. The first and second body panels 1012 a, 1012 b are joined along a pair of opposing sides and a bottom bridging the sides so as to form an open mouth. The joined first and second body panels form an interior space for storing items. The freshness-extension structure 1014 is in the form of a patch or tape and comprises two layers, e.g., a first layer 1016 being a barrier layer and a second polymeric layer 1019 being a diffusion layer and including a freshness-extension agent.
As shown in FIG. 12 a, the removable cover 1021 is similar to that of FIG. 8, but is securely attached to panel 1012 b. The removable cover 1021 covers at least a portion of the second layer 1019, and, as shown, preferably covers the entire second layer 1019 that is otherwise exposed in the interior of the package 1010. As shown in FIG. 12 b, removal of the cover 1021 exposes the freshness-extension layer 1019 to the interior of the package 1010 and thereby begins or enhances release of freshness-extension agent thereto at least while the package is open. This embodiment of FIGS. 12 a and 12 b is particularly suitable for waste bags and liners or the like.
According to yet another aspect of the invention, the agent structure, e.g., freshness-extension structure, is configured for selective dosing of an active agent. Such selective dosing, as described herein is achieved by different configurations for covering the freshness-extension agent or otherwise preventing activation and release of the freshness-extension agent.
Generally, and in accordance with the invention, a plurality of covers are provided to cover a predetermined region of the freshness-extension agent. The covers can be coterminous with the region of freshness-extension agent. Alternatively, the cover can extend beyond the region of freshness-extension agent, in which case the covers are typically at least partially attached to a surrounding structure, such as a wall or body panel of the package, to further contain the active agent.
As shown in FIG. 13, the freshness extension structure 1300 includes removable covers in the form of multiple covers 1310. If desired, the covers can be provided as separate members. Alternatively, and as depicted in FIG. 13, the covers 1310 can be attached along a line of weakness 1320, to be partially attached, for example, along a common edge by way of a small connecting portion. The line of weakness, which is a preferential area of weakness can be provided as a perforation, as illustrated in FIG. 13, or another feature that allows relatively easy separation of adjacent portions. The line of weakness can alternatively be provided by way of creating a score line, forming the covers with an area of reduced material thickness, or by forming the covers to have an area of highly oriented plastic, such that the material has a tendency to split along the line of weakness or another suitable method. Alternatively, adjacent covers can be mutually attached to one another, such as by an adhesive or other connection that is easier to break than the cover material itself.
The freshness extension structure 1300 is shown mounted to a wall or body panel B of a package. In this embodiment, as well as in others, peelable areas 1330 facilitate removal of each cover portion from the freshness-extension structure 1300. When initially activating the freshness-extension structure 1300, the user will remove one or more of the covers 1310, depending on the implementation, as described in detail below in connection with FIGS. 20 and 21, for example. For example, the user can remove and separate the first cover 1310 a from the adjacent cover portion 1310 b along the common line of weakness 1320. As the freshness-extension agent is consumed, the user can remove one or more cover portions, such as cover portion 1310 b, and so on. Alternatively, if the container being utilized is relatively large or additional antimicrobial protection is desired, more than one cover portion may be removed at any one time.
The term peelable area, as used herein, such as peelable area 1330, are areas that facilitate easy removal of the covers. As illustrated in FIG. 23, for example, the peelable areas 2315 and 2325 can be created by the insertion of an intervening release element 2317. Such release element 2317 can be, for example, simply a layer of material that precludes adhesion between the corner of the cover portion 2310 and the underlying layer 2340. The underlying layer 2340 can be, for example, a freshness extension layer, barrier layer or a body panel of a package, depending on the specific embodiment. Alternatively, the peelable region can be created simply by an absence of an underlying adhesive or other adhering substance in that region. As illustrated, the second cover portion 2320 also has a peelable region 2325 which is accessible to a user once the cover 2310 is removed and separated along the line of weakness 2327.
Alternatively still, the multiple covers or cover portions can be completely separate from one another. FIG. 17, for example, illustrates a freshness extension structure 1700 having three removable covers 1710, 1720 and 1730. In this embodiment, a portion 1735 of the leftmost cover 1730 overlaps a portion of the middle cover 1720. A portion 1725 of the middle cover 1720 overlaps a portion of the rightmost cover 1710. These overlapping regions 1735 and 1725 are less securely adhered, if at all, to the underlying surface than the remaining area of the covers 1720 and 1730. The less secure adhesion facilitates removal by a user, so that these regions can be used as a peelable area for removal of the corresponding cover. The rightmost cover 1710, in-turn, has a peelable area 1715, similar to that of FIG. 23 for example, to facilitate to facilitate removal of cover 1710.
FIG. 14 illustrates another embodiment of the invention, in which a portion 1415 of a freshness-extension layer or region 1410 is disposed on a wall of package B with a portion initially exposed. As such, the freshness-extension agent is immediately available for activation to deliver antimicrobial protection within the package. Such an embodiment is desirable for incorporation with packaged produce, or other perishable goods. The contents of the package therefore immediately benefit from the freshness-extension effect of the active agents contained within the freshness extension structure 1400. A cover 1420, which may or may not itself be divided into additional covers, is shown as extending beyond the border of the freshness extension layer or region 1410, and can be adhered to the body panel in this region. Alternatively, the cover 1420 can be conterminous with the freshness extension region 1410 if desired. Additionally, a seal 1430 can be provided along a border of the freshness-extension layer 1410 to prevent freshness-extension agent from being consumed or released along the border region.
Alternatively, the exposed area 1415 of the freshness extension structure 1400 of FIG. 14 can be sealed from activation by way of an opposing wall or body panel of the package. As such, an economical automatic application of active agents is achieved. In such a case, the material selected for the opposing wall or body panel acting as a cover is suitable to be used as a barrier layer, as previously described, to prolong the life of the active agents.
In the freshness-extension structure 1500 of FIG. 15, a plurality of covers 1520, 1530 a, 1530 b are provided. One cover portion 1520 is completely separated from the remaining cover portions 1530, which is shown as including a sub-division of covers 1530 a and 1530 b, separated by a line of weakness 1533. Peelable regions 1537 on covers 1530 a and 1530 b are provided at one end thereof. As depicted, the covers 1520, 1530 are attached in regions 1525 and 1535, in this embodiment, at least partially around the freshness extension layer or region 1540, to a body panel of a package, for example. Although not required, a gap 1510 is shown between the covers 1520, 1530, which can be of any size. The gap 1510 can be relatively large to provide immediate antimicrobial protection as in the embodiment of FIG. 14, or can be minimized or eliminated to substantially prevent immediate activation and release of the freshness-extension agent.
Moreover, the separate covers 1520 and 1530 advantageously allow attachment of the covers 1520 and 1530—with one secured to a different component of the package so as to be removed when the package is opened. For example, a reclosable bag typically comprises two opposing body panels joined along a portion of the periphery. Both cover portions 1520 and 1530 can be removably attached to an underlying body panel of the bag, as illustrated in FIG. 15, and the cover portion 1520 further can be secured to the opposing body panel of the bag. When the reclosable bag is opened by a user, the body panels are separated and the cover portion 1520 is removed from the freshness extension layer or region 1540. Alternatively still, and as previous described, the opposing body panel to which the cover portion 1520 is otherwise secured, can itself function as the cover, thereby obviating the need for cover portion 1520. In such an arrangement, the appearance of the structure would be similar to that of freshness-extension structure 1400, where the dedicated cover 1420 only partially covers the freshness-extension layer or region 1410.
FIG. 16 illustrates a freshness-extension structure 1600, which is a variation of freshness extension structure 1300. Covers 1610, 1620, 1630 1640, 1650 and 1660 cover a freshness-extension layer or region. The covers in this embodiment, as in freshness extension structure 1900, vary in size. Peelable regions 1615, 1625, 1635, 1645, 1655 and 1665 facilitate easy removal of the covers, which are dividable along lines of weakness 1613. Freshness-extension structure 1900 of FIG. 19 is not provided with peelable regions for purpose of illustration. Also, unlike the linear arrangement of covers as in freshness-extension structure 1600, the covers 1941-1949 are configured in an irregular array, with some covers being larger than others.
FIG. 18 illustrates freshness-extension structure 1800, which is a further variation on the freshness extension structure 1300 of FIG. 13. In this freshness-extension structure 1800, the covers 1810-1814 are linearly arranged, with respective peelable areas 1820-1824, and are defined by lines of weakness 1830-1833. The strip-shaped covers 1810-1814, as with the covers of every other embodiment, may be embodied in any number in the freshness-extension structure 1800, though only five covers 1810-1814 are illustrated.
Any number of covers can be provided for the predetermined region of active agent in accordance with another aspect of the invention, however, a specified number of covers can be provided for a particular purpose. For example, and as illustrated in FIGS. 20 and 21, the precise number of covers regions can correspond to a desired number, such as days in a week (i.e., 7) or month (e.g., 30). As such, the freshness extending agent can be released by a user at a predetermined rate (e.g. mg/day) over an extended period of time at the desired level. Moreover, in connection with such embodiments, the size of the covers to be removed can be configured to vary over a prescribed time period. For example, as time passes during the storage of a perishable item, the item may be more susceptible to spoilage or otherwise require increased levels of an antimicrobial atmosphere to increase the storage life of the item. The user therefore can remove increasingly larger covers as shown, for example, in FIGS. 16 and 19. The sizes of such covers can be predefined, and may be labeled by such indicators as “day 1” “day 2” et cetera, as shown by indicia areas 2031 and 2032 of the freshness-extension structure 2000 of FIG. 20. Alternatively, the covers can be unlabeled, leaving the size or number of covers removed at any time to the discretion of the user. The freshness-extension structure 2000, and other embodiments thereof, have also a region 2050 for recording of the date first activated. Based on this date and the assumed lifespan of the freshness-extension structure 2000, the user can determine the date after which the contents of the container should be discarded, such as for prepackaged goods. The area for recording such date can be located as desired, for example on the border region 2060, adjacent the region 2050 for recording the initial start date.
In another aspect of the invention, such varying size covers need not be for the purpose of use over an extended period of time, as described above. The present invention provides the ability to tailor the amount of activated antimicrobial material to a size of a selected container or product to be contained therein. This can be particularly useful when the freshness-extending structure is made available separate from the package. For example, if a user has previously purchased an assortment of resealable and reusable plastic containers, the user may desire to extend freshness of food or perishables stored in these containers. The agent structure can be made in the form of patches, pouches or tapes for use with such packages or containers. Because the sizes of the packages or containers can vary, the user can select the amount of active agent contained within the agent structure to deliver for the desired performance. Hence, the agent structure can be provided in a variety of different sizes, or the agent structure can be provided with a plurality of equally-sized removable covers or varied-sized removable covers if desired. Accordingly, the ability to tailor the amount of release of antimicrobial agent for a particular container provides an additional benefit.
In accordance with one aspect of the invention, the user estimates the quantity of area of antimicrobial structure to expose to achieve effective antimicrobial protection. In another aspect of the invention, the covers or active regions of the subject antimicrobial structure are divided in a preselected arrangement to offer a recommended amount for the user based upon the size of the package and/or the contents to be stored therein. Additionally, the covers can include information or instructions to the user to guide the user in removing an appropriate number of covers. Such instructions can be embodied on the removable covers of the agent structure in the form of a table provided on a backside of the agent structure or in separate instructions. An example table providing user guidance is below in Table 1. As set forth above, the covers can be completely independent covers or attached by lines of weakness, and can be provided in equally-sized regions or in regions of varied sizes. For example, covers can be provided in one-inch by one-inch squares on a four-inch by four-inch patch. The user then, has the option of removing between zero and sixteen covers, simultaneously or sequentially over time, depending on the size of the container to be used, or as mentioned above, the desired level of active agent in the package. As an alternative, the covers can be further sub-divided. For example, some or all of the sixteen 1-inch square covers can be divided again into smaller regions to enable further tailoring of the freshness-extending characteristics of the agent structure.

In Table 1 below, if included with a freshness-extension structure, the user is provided with a guide having instructions regarding how many covers or cover portions to remove for any given container volume and level of freshness-extension. The volume can be provided in any unit. Alternatively, rather than container volume, container designations can be provided as an easy reference to the consumer. If a manufacturer provides a particular designation for a given size container, such information can be correlated to the amount of freshness-extension area to expose. Further, if the user desires increased freshness-extension, the guide table (e.g., Table 1) can provide guidelines for effecting such protection. Additionally, and as previously noted, the table can be arranged in accordance with the type and/or amount of product to be contained in the package.

TABLE 1


approx.
container
volume	Example container	regular extension	extra extension

75 cubic	4″ d/1.5″ h or	6.5 covers/week	12.5 covers/week
inches	5″ × 5″ × 3″
30 cubic	Container model #	3 covers/week	5 covers/week
inches	xxxxxx

FIG. 21 illustrates a variation of a freshness-extension structure 2100 in which the user is provided a plurality of freshness-extension regions such as freshness-extension regions defined by covers or covers 2101-2105. In this embodiment, the peelable regions, such as peelable regions 2111, 2112 and 2115 are provided in corners of the covers. However, since the covers are arranged in an array and the peelable regions preferably have a lower adhesion to the underlying layer than do the remainder of the covers, the peelable regions are alternatingly provided at the top of the covers, as the user passes from row to row. This helps prevent removal of more than one cover at a time. For example, as the user removes cover portion 2101 by gripping peelable area 2111, the cover is intuitively pulled diagonally to the lower right. Because in the second row, the peelable regions are located in the upper-right corner of the covers (e.g., cover portion 2105 and peelable area 2115), the action of removal of cover portion 2101 does not lift the cover 2105 at the peelable area 2115 and thereby begin the undesired removal of the cover portion 2105.
Freshness-extension structure 2100 further includes an indicia area 2130 for display of indicia 2135 such as user instruction, warnings, expiry dates or any other communication that is desired. This indicia area can be provided on a removable cover or on a secured area not capable of being removed.
FIGS. 22 a and 22 b illustrate front and cross-sectional views of two embodiments of freshness extension structures 2200, 2300 in which the freshness-extension agent is incorporated into the body panel B of a container in a predetermined region R in a manner previously described. As with the previous embodiments, a plurality of covers 2210, 2220 (independent or attached together) cover the predetermined region R. The covers 2210, 2220 of FIG. 22 a extend beyond the freshness-extending region R; the covers of freshness extension structure 2300 are coterminous with region R. Peelable areas 2215, 2217 are provided on opposite upper corners of the freshness-extension structure 2200 to facilitate user-removal of the covers from the underlying layer.
In another embodiment of the invention, the structure is provided in the form of a stripe, i.e., a form having a length longer on one side than the adjacent side. When the patch is provided as a stripe, the active agent is disposed on the stripe material by being sprayed, brushed, coated, laminated, or stamped on the material; extruded with the material; impregnated into the material; and/or distributed in the material, such as in the form of microcapsules. The stripe material can be formed, e.g., cut, into desired size before or after the active agent is disposed on the material. For example, the stripe can be extruded or otherwise formed continuously along a web material, which in turn can be made into a desired package or wrap.
Advantageously, the stripe can be provided in any desired size. In one exemplary embodiment, the stripe can be formed to run the entire length of the package. For example, a stripe of 0.25 inches in width can be disposed along the wall of a package, or formed integrally with the wall of the package. Thus, the stripe can be easily applied inline with the package. The stripe is especially advantageous in that it provides a continuous surface area, and therefore a large amount of active agent, while appearing smaller than, for example, a square shape. Additionally, the stripe can be disposed along the mouth of a bag, for example, to enhance performance and delivery of the active agent. If formed separate from the package, the stripe is conveniently disposed on the package with, e.g., an adhesive, cohesive, or heat sealing or welding techniques.
FIG. 24 illustrates a freshness-extension structure 2400 where the structure 2400 is relatively long relative to its width, such a stripe or tape 2410, for example. The covers 2411 can be applied along the length of the structure 2400, and divided by lines of weakness (e.g., line of weakness 2413). The structure 2400 can be mounted in or on the wall of any of a variety of packages. In one preferred embodiment, the structure 2400 is mounted on a wrap or foil material, such as a plastic food wrap or aluminum foil. Alternatively, the wrap can form a barrier layer with the active agent applied in the form of a stripe, then covered by a series of removable covers.
In some embodiments, the removable cover 1021 can cooperate with a slider of the fastener of the reclosable package 1010, so that the removable cover can be removed from the freshness-extension layer when the reclosable package 1010 is opened via the slider.
The freshness-extension structures of the present invention, such as a patch, tape, or pouch, can be attached to a package such as a reclosable bag by a pressure-sensitive self-adhesive. The pressure-sensitive self-adhesive can be any suitable adhesive that attaches the freshness-extension structure to the reclosable package. Non-limiting examples of pressure-sensitive adhesives that can be used include acrylic or rubber-based adhesives.
The freshness-extension structure being a tape or pouch can be roll fed onto a layer(s) of the reclosable package. The roll-fed freshness-extension structure being a tape or pouch can also initially include a release liner that assists in preventing or inhibiting the freshness-extension agent from sticking to itself before delivery to the reclosable package. The release liner, if used, is separated from the roll-fed freshness-extension tape or pouch before the tape or pouch is attached to the reclosable package or bag. Examples of release liners include silicon-coated paper. Release liners, however, may be undesirable because of the additional cost associated therewith. It is contemplated that the freshness-extension structure can be roll fed without the use of a release liner before being attached to the reclosable package or bag.
Alternatively, the freshness-extension structure being a patch or pouch can be magazine fed during attachment to the reclosable package. The patch is preferably magazine fed, while the pouch can be magazine or roll fed. The tape is preferably roll fed during attachment to the reclosable package. For example, the tape can be unwound, cut to length and attached to the reclosable package.
According to another embodiment, the freshness-extension structure patch, tape, or pouch can be heat sealed or welded (e.g., ultrasonically welded) directly to the reclosable package or bag. The freshness extension structure can be roll fed or magazine fed before being heat sealed or welded to the reclosable package. In a heat-sealing embodiment, a release liner would not likely be used because the freshness-extension structure without any adhesive should not stick to itself and the release liner adds an unnecessary cost. The freshness-extension structure can be attached to the reclosable package at several locations. The freshness-extension structure can be attached to the body panels during the formation of the heat seals. For example, the freshness-extension structure may be located between a side seal formed between the first and second body panels. It is contemplated that other attaching methods can be used.
The reclosable packages, such as reclosable package 10, can be formed of any suitable material, such as by a thermoplastic material suitable for storing or collecting items, including perishables storage. This, of course, includes common-sized reclosable packages such as pint storage and freezer bags, quart storage and freezer bags, and gallon storage and freezer bags. The reclosable packages are typically formed from polymeric materials such as polyolefinic materials. Non-limiting examples of polyolefinic materials include polyethylenes, polypropylenes, polystyrene, and combinations thereof. For example, some types of polyethylenes materials include high density polyethylenes (HDPE), low density polyethylenes (LDPE), linear low density polyethylenes (LLDPE), and combinations thereof. It is also contemplated that materials such as plastomers, elastomers, ethylene vinyl acetates (EVA), ethyl methacrylates, polymethylpentene copolymers, polyisbutylenes, polyolefin ionomers, cyclic olefin copolymers (COCs) or combinations thereof, including polyethylenes, and/or polypropylenes may be used in forming the reclosable packages of the present invention. The thicknesses of the reclosable packages can vary in the present invention, but are generally from about 0.5 mil to about 5 mils and, more specifically, from about 1 mil to about 3 mils.
As previously described herein, the freshness-extension agents of the present invention can be used in combination with a body panel of a package. Alternatively and/or in combination, the freshness-extension agents of the present invention can be used in combination with fin portions of a fastener of a reclosable package, as further described in co-pending U.S. patent application Ser. No. 11/055,574, the contents of which application are expressly incorporated by reference herein in its entirety.
While the disclosed packages with active agents have been shown and described with reference to the illustrated embodiments, those of ordinary skill in the art will recognize and/or be able to ascertain many equivalents to those embodiments. Such equivalents are encompassed by the scope of the present disclosure and the appended claims.
For example, those of ordinary skill in the art will understand that the present invention has applications to various types of packages and containers, including non-reclosable bags and liners, rigid containers such as plastic containers, lunch boxes, and rigid trash containers, and perishable packaging wraps and foils. Similarly, those of ordinary skill in the art will understand that the present invention has applications to active agents other than freshness-extension agents, such as odor management agents and other agents providing a desired function or effect on a package or the contents disposed therein.
Unless otherwise provided, when the articles “a” or “an” are used herein to modify a noun, they can be understood to include one or more than one of the modified noun.

Claims

1. An agent structure comprising:

a base layer including an active agent in a predetermined region; and

a plurality of removable covers removably covering the predetermined region, each removable cover covering an area less than an entire area of the predetermined region.

2. The agent structure of claim 1, wherein each removable cover includes a peelable area to facilitate removal by a user.

3. The agent structure of claim 1, wherein at least two adjacent removable covers are joined together along a line of weakness.

4. The agent structure of claim 1, wherein each removable cover includes a barrier layer.

5. The agent structure of claim 1, wherein at least one removable cover includes a diffusion layer.

6. The agent structure of claim 5, wherein the at least one removable cover further includes an outer barrier layer separable from the diffusion layer, the outer barrier layer capable of being removed from the predetermined region separately from the diffusion layer.

7. The agent structure of claim 1, wherein the base layer is made of a diffusion material with the active agent contained therein.

8. The agent structure of claim 1, further comprising a barrier layer, the base layer including the active agent disposed between the base layer and the removable covers.

9. The agent structure of claim 1, further comprising a diffusion layer disposed between the base layer and the removable covers.

10. The agent structure of claim 1, wherein the agent structure is a tape.

11. The agent structure of claim 1, further comprising a layer of adhesive, cohesive or static promoting material on a side of the base layer opposite the removable covers.

12. A package comprising:

a wall forming at least a portion of the package;

an active agent disposed in a predetermined region of the wall; and

13. The package of claim 12, wherein the active agent is incorporated into the wall at the predetermined region.

14. The package of claim 13, wherein the active agent is extruded with the wall.

15. The package of claim 12, wherein the active agent is included in an agent structure disposed on a surface of the wall.

16. The package of claim 12, wherein the package is a bag; the wall forming at least a portion of a pair of opposing panels joined together along opposing sides and a bottom bridging the sides.

17. The package of claim 16, wherein the predetermined region is located on one of the pair of opposing panels; at least one of the plurality of removable covers covering the predetermined region is further secured to the panel opposite the predetermined region so as to be removed from the predetermined region when the opposing panels are spaced from each other.

18. The package of claim 12, wherein the wall is formed of a barrier material.

19. The package of claim 12, wherein the package is a generally rigid container, the wall defining at least a portion of the generally rigid container.

20. The package of claim 12, wherein the package is defined at least in part by a wrap material, the wall forming the wrap material.

21. The package of claim 12, wherein the active agent is a freshness-extension agent, antimicrobial agent, odor management agent, color indicator, spoilage indicator or fragrant.

22. A wrap material comprising:

a web material;

an active agent disposed in a predetermined region of the web material; and