WO2014151414A2

WO2014151414A2 - Removable film tape article

Info

Publication number: WO2014151414A2
Application number: PCT/US2014/025681
Authority: WO
Inventors: Josh M. BOGNER; Robert W. Schneider
Original assignee: Avery Dennison Corporation
Priority date: 2013-03-15
Filing date: 2014-03-13
Publication date: 2014-09-25
Also published as: WO2014151414A3

Abstract

A removable, adhesive-backed article is disclosed. The article uses particular adhesive compositions and pull tab configuration to provide aesthetically attractive, securable, and easily removable articles such as wall hooks.

Description

REMOVABLE FILM TAPE ARTICLE

CROSS REFERENCES TO RELATED APPLICATIONS

[0001] The present application claims the benefit of U.S. Provisional Application No. 61/788,861 filed March 14, 2013, which is incorporated herein by reference in its entirety.

FIELD

[0002] The present subject matter relates to articles that can be securely adhered to a substrate such as a wall and selectively released therefrom by use of a pull tab. A particular example of such articles is a wall hook.

BACKGROUND

[0003] Many attempts have been made in the past to provide hangers which may be secured to a wall without nails so as to avoid making holes in the walls, cracking plaster, or otherwise damaging the wall surface. Such hangers have also been sought in order to permit the hanging of objects on fragile surfaces, such as marble, glass or tile, which would be irreparably damaged by conventional hangers using nails. Although certain adhesive hangers are known which are satisfactory, many suffer from disadvantages, such as their inability to support objects substantially heavier than ten pounds, and their difficulty in removal, particularly without damage to an underlying surface.

[0004] Certain known adhesive hangers can be removed by applying a solvent between the hanger and the surface to which it is attached. That practice is undesirable as the solvent may stain or leave visible residue on the surface. It is also known that applying heat along the bond region may debond the adhesive. Heating is not always practical and at a minimum is inconvenient.

[0005] Adhesive hangers are also known which include a movable enclosure that provides access to a gripping member which is mechanically attached to adhesive within the hanger. Such hangers are removed by moving or positioning an enclosure to reveal the gripping member which a user then pulls to dislodge the adhesive. Although these types of hangers alleviate some of the previously noted problems, a need remains for an improved article and removal strategy which is simple, inexpensive, and does not involve slideable or moveable enclosures. [0006] Accordingly, a need remains for an adhesive article which can be securably attached to a wall or other substrate and which can be readily removed without damaging the surface. Furthermore, a need also exists for an adhesive article that does not require solvents, heat, or complicated operations to remove the article after adherence.

SUMMARY

[0007] The difficulties and drawbacks associated with previously known adhesive articles are addressed in the present articles and related methods directed to selectively releasable, pull tab actuated articles.

[0008] In one aspect, the present subject matter provides a removable article comprising a carrier defining a first face and an oppositely directed second face. The article also comprises a substrate- facing adhesive disposed on the first face of the carrier. The article also comprises an article-facing adhesive disposed on the second face of the carrier. And, the article comprises a structural member disposed on and contacting the article-facing adhesive. The carrier includes a carrier portion extending beyond an edge of at least one of the substrate-facing adhesive, the article-facing adhesive, and the structural member.

[0009] In another aspect, the present subject matter provides a removable article comprising a polymeric carrier defining a first face and an oppositely directed second face. The article also comprises a substrate-facing adhesive disposed on the first face of the carrier. The article additionally comprises an article-facing adhesive disposed on the second face of the carrier. And, the article also comprises a structural member disposed on and contacting the article-facing adhesive. The substrate-facing adhesive generally exhibits a lower tackiness than the article-facing adhesive.

[0010] In still another aspect, the present subject matter provides a method of treating an adhesive article having a carrier, two layers or regions of adhesive on oppositely directed faces of the carrier, and a structural member disposed on and contacting one of the adhesive layers. The method comprises exposing at least one of the adhesive layers to electron beam radiation.

[0011] The subject matter described herein is capable of other and different embodiments and its several details are capable of modifications in various respects, all without departing from the claimed subject matter. Accordingly, the drawings and description are to be regarded as illustrative and not restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a schematic, exploded perspective view of a removable film tape article in accordance with the present subject matter.

[0013] Figure 2 is a schematic partial cross-sectional view of the removable film tape article of Figure 1.

[0014] Figure 3 is a schematic partial cross-sectional view of the removable film tape article of Figures 1-2 being removed from a vertically oriented substrate.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The present subject matter relates to adhesive articles which can be securely attached to a substrate by an adhesive incorporated in the article, and selectively released from the substrate by actuation of a pull tab also incorporated in the article. The articles generally comprise a polymeric carrier defining a first face and an oppositely directed second face. An effective amount of a substrate- facing adhesive is disposed on the first face of the polymeric carrier, typically in a layer form. Disposed on the second face of the carrier is an effective amount of an article-facing adhesive. The article-facing adhesive is typically in the form of a layer on the second face of the carrier. The articles also comprise one or more structural member(s) such as hooks that are in contact with and adhered to the layer or region of the article-facing adhesive. An optional release liner or protective layer can be provided to cover the otherwise exposed face of the substrate-facing adhesive prior to use.

[0016] In certain versions of the present subject matter, the polymeric carrier extends beyond an edge or peripheral region of the adhesives, and typically also extends beyond the structural member(s) to thereby facilitate grasping of the carrier. The article is adhered to a substrate of interest such as a wall by orienting the substrate-facing adhesive toward the wall and then contacting that adhesive with the wall. The substrate-facing adhesive provides a secure adhesive bond between the wall and the structural member(s).

[0017] The article can be readily removed from the wall by grasping an exposed region or end of the polymeric carrier constituting the pull tab, and pulling that member away from the wall. Displacement of the carrier and substrate-facing adhesive from the wall results in separation of the substrate-facing adhesive from the wall. In certain versions of the present subject matter, particular compositions are used for the substrate-facing adhesive and the article-facing adhesive, which may be the same or different from one another. In still further versions of the present subject matter, particular configurations are used for the adhesive face for contacting the substrate of interest. Particular embodiments are provided for the carrier and its pull tab portion. These and other aspects are all described in greater detail herein.

Substrate-Facing Adhesive

[0018] The substrate-facing adhesive is typically a removable adhesive. A "removable adhesive" is defined herein as an adhesive which can be readily repositioned and which exhibits residue-free removability. That is, upon removal from most substrates, the adhesive does not leave any visible residue as to its previous contact and/or adherence with the substrate.

[0019] In one embodiment, the removable adhesive comprises a rubber based pressure sensitive adhesive. The rubber based adhesives are typicaiiy hot melt or solvent pressure sensitive adhesives.

[0020] in one embodiment, the removable adhesive comprises one or more rubber elastomers and a tackifier. The ru bber e!astomer(s) is generally present in an amount from about 20% to about 48%, or from about 25% to about 40%, or from about 28% to about 37% by weight of the removable adhesive. Useful rubber elastomers include the block polymers of styrene and dienes, as well as ethylene-propylene elastomers, including diene terpo!ymers, styrene olefin copolymers like styrene ethylene, propylene or butylene block polymers. Styrene diene polymers are particularly useful, such as styrene isoprene copolymers and styrene butadiene copolymers.

[0021] In another embodiment, the rubber elastomer comprises a mixture of triblock and diblock copolymers. The rubber elastomers are generally styrene isoprene or styrene butadiene block copolymers. The triblock content is typically from about 30% to about 70%, or from about 35% to about 65%, or from about 40% to about 60% by weight of the rubber elastomer. The diblock content is from about 70% to about 30%, or from about 65% to about 35%, or from about 60% to about 40% by weight of the rubber elastomer.

[0022] The tackifier system of this embodiment includes of tackifiers that are preferentially miscibie with at least the po!ydiene having the highest glass transition temperature, for example., poiyisoprene. Tackifier systems used in the practice of the present subject matter, while including conventional tackifiers and plasticizer oils, should also have the net effect of being preferentially soluble in the poiyisoprene block. [0023] In certain embodiments, the polymers used in formulating the pressure sensitive adhesives are based on natural and/or synthetic elastomeric polymers. Useful are AB_; ABA and (AB)x block copolymers wherein x has a value of 3 or more and wherein A is a block comprising at least one monoalkenyl arene, preferably styrene, alpha methyl styrene, vinyl toluene and the like, and B is an elastomeric conjugated diene block, preferably a polybutadiene or a polyisoprene block. Preferably at least one is based on polybutadiene blocks and one other is based on polyisoprene blocks. These include, but are not limited to, homopolymers, block, random or multi-armed copolymers, and mixtures thereof. Among the useful elastomeric polymers there may be mentioned natural rubber (polyisoprene), polybutadiene, synthetic polyisoprene, random styrene-butadiene polymers, styrene-butadiene (SB) block copolymers, multi-armed and repeating (SB) copolymers, styrene-butadiene-styrene (SBS) block copolymers, styrene-isoprene (SI) block copolymers, styrene-isoprene-styrene (SIS) block copolymers, multi-armed styrene-isoprene (Sl)x block copolymers, and the like. It will be understood that random copolymers may also be used.

[0024] Commercially available elastomeric polymers which can be used in certain embodiments of the present subject matter include linear SIS/SI block copolymers known as KR.ATO ^® D-1107 and D- 1112, SBS/SB block copolymers known as K RATON^® D-1101, D-1102 and DX-1300, and an (Sl)x block copolymer known as KRATON^® D-132.0X, all manufactured and sold by Shell Chemical Company, and an SB block copolymer known as SOLPRE E^® 12.05 manufactured and sold by Dynasol Elastomers. As indicated, in many of the SIS or SBS block copolymers, there are respectively present SI or SB components.

[0025] Certain elastomers, such as the ethylene-propylene diene rubbers, styrene- ethylene/butyiene, styrene block copolymers, styrene-ethylene/propylene-styrene block copolymers and the like, may also be used.

[0026] Tackifier additives for certain polyisoprene components are described in US Patent No. 3,577,398 and US Patent No. 3,692,756. These hydrocarbons range from materials that are normally liquid at room temperature to those that are normally solid at room temperature and typically contain 40% or more by weight polymerized dienes. The dienes are typically piperyiene and/or isoprene. They are available from Total as the WINGTACK^® family of resins.

[0027] Other normally solid tackifiers are E5COREZ™ 1310 LC manufactured by Exxon and PICCOTAC™ 95 manufactured by Eastman Chemical Company. [002S] Other additives that serve a tackifier function include hydrogenated aromatic resins wherein a very substantia! portion, if not all, of the benzene rings are converted to cyclohexane rings (for example, the REGALREZ™ family of resins manufactured by Eastman Chemical Company such as REGALREZ™ 1018, 1033, 1065, 1078 and 1126, and REGALITE™ R-100, and the ARKON family of resins from Arakwa Chemical such as Arkon P-85, P-100, P-115 and P-125), hydrogenated polycyclic resins (typically dicyclopentadiene resins such as ESCOREZ™ 5300, 5320, 5340 and 5380 manufactured by Exxon) and the like.

[0029] There can be also added rosins, rosin esters, polyterpenes and other tackifiers that are compatible to some degree with the poiyisoprene and poiybutadiene phases. Other additives include plasticizer oils such as SHELLFLEX 371 manufactured by Shell Lubricants and KAYDGL^® mineral oil available from Sonneborn Products which are soluble in both the poiyisoprene and poiybutadiene phases.

[0030] The tackifier system may be present in an amount, based on the total weight of tackifier system and elastomers, of from about 40% to about 80% by weight, or from about 50% to about 70% by weight, or from about 60% to about 70% by weight.

[0031] The substrate-facing adhesive also comprises one or more fillers. The filler is typically present in an amount less then 40% by weight of the adhesive (excluding solvent). In one embodiment, the filler is present in an amount from about 5% to about 40%, or from about 10% to about 35%, or from about 25% to about 35% by weight. Here and elsewhere in the specification and claims, the percentage range may be combined. Combinations of fillers may be used. When a combination of fillers is used, the combined amount is reflected in the above percentages. The filler includes carbon black, calcium carbonate, titanium dioxide, clay, diatomaceous earth, talc, mica, barium sulfate, aluminum sulfate, silica, or mixtures of two of more thereof.

[0032] In another embodiment, a useful filler combination includes an anti-blocking agent, which is chosen depending on the processing and/or use conditions. Examples of such agents include for example silica, talc, diatomaceous earth, and any mixtures thereof. The filler particles may be finely divided substantially water-insoluble inorganic filler particles.

[0033] The finely divided substantially water-insoluble inorganic filler particles can include particles of metal oxides. The metal oxide constituting the particles may be a simple metal oxide (i.e., the oxide of a single metal) or it may be a complex metal oxide (i.e., the oxide of two or more metals). The particles of metal oxide may be particles of a single metal oxide or they may be a mixture of different particles of different metal oxides,

[0034] Examples of suitable metal oxides include alumina, silica, and titania. Other oxides may optionally be present in minor amount. Examples of such optional oxides include, but are not limited to, zirconia, hafnia, and yttria. Other metal oxides that may optionally be present are those which are ordinarily present as impurities such as for example, iron oxide. For purposes of the present specification and claims., silicon is considered to be a metal.

[0035] When the particles are particles of alumina., most often the alumina is alumina monohydroxide. Particles of alumina monohydroxide, AIO(OH), and their preparation are known.

[0036] Without being limited to any particular theory, it is believed that the filler creates a physical crosslinking system that increases cohesive strength of the substrate-facing adhesive. In addition, the filler reduces active sites for adhesion that reduce the removal force. In certain versions of the present subject matter, the filler has a surface chemistry that allows for bonding to create or promote a physical crosslinking network within the substrate-facing adhesive. Thus, in certain embodiments, the outer surface of the filler particulates for example can be hydroxyl functionalized to aid in bonding.

[0037] The substrate-facing adhesive can be cured and/or crosslinked. For example, the adhesive can be cured and/or crosslinked by exposure to electron beam, UV light, and/or other radiation sources. Curing and/or crosslinking can also be effected by thermal means. Incorporation of one or more photoinitiators in the adhesive is contemplated.

[0038] The substrate-facing adhesive can comprise additional components such as, but not limited to antioxidants, solvent(s), plasticizer oils, flame retardants, optical brighteners, and combinations thereof.

[0039] An example of a suitable solvent is toluene. An example of a commercially available plasticizer is STAYBELITE™ Ester 3-E Ester of Hydrogenated Rosin, available from Eastman Chemical of the Netherlands. An example of a commercially available flame retardant is SAYTEX^® 8010 Flame Retardant from Albermarle Corporation of Baton Rouge, Louisiana.

[0040] The present subject matter also includes the use of particular foamed or low density adhesive compositions for the substrate-facing adhesive. In certain applications, such adhesives can be deposited upon and/or disposed alongside a face of the carrier and in relatively high thicknesses. The adhesives can be pressure sensitive adhesives. The adhesives exhibit excellent gap-filling properties, while concurrently providing pressure sensitive adhesive characteristics. [0041] In one embodiment of the present subject matter, particular proportions of expanda ble polymeric hollow microspheres are incorporated into the substrate-facing adhesive. The hollow polymeric spheres employed are typically of the type disclosed in U.S. Patent No. 3,615,972, which describes various vinyl polymers containing a hydrocarbon liquid that volatilizes at a temperature slightly below the softening point of the polymeric spheres. Thus, a sphere that is originally on the order of 10 micrometers in diameter, when heated to a temperature of, e.g., 120° C, is expanded to an average diameter of e.g., 30-60 micrometers. It is possible to include the unexpanded microspheres in the adhesive composition and subsequently heat them to effect expansion, but it is generally preferred to mix the expanded microspheres directly into the adhesive, a process which makes it easier to ensure that the hollow microspheres in the final adhesive are substantially completely surrounded by at least a thin layer of the adhesive. The polymeric microspheres mentioned can be added to an adhesive system after the adhesive matrix has been polymerized.

[0042] Microspheres and their methods of preparation are described in U.S. Patents No. 3,615,972, 4,075,138, and 4,287,308. The microspheres are available from the Pierce & Stevens Company under the trade name MIC OLITE in unexpanded form and MIRALITE in expanded form. Similar microspheres are available from Kema Nord Plastics under the trade name EXPANCEL, from Matsomoto Yushi Seiyaku under the trade name MICROPEARL, and formerly from Dow Chemical Company under the trade name SARAN. In expanded form the microspheres have a specific density of approximately 0.01-0.04 g/cm, typically 0.02-0.036 g/cc. Perhaps because of the thin, flexible shells of such microspheres (on the order of 0.02 micrometer according to trade literature), their rough surface, or their organic nature, they appear to be mechanically and/or chemically bonded to the adhesive composition in which they are incorporated, becoming almost an integral part of the adhesive mass, distorting when the mass is subjected to pressures, distributing stress, absorbing energy, and exhibiting distinctly different characteristics from otherwise identical adhesive compositions incorporating only hollow glass or other rigid microspheres.

[0043] Addition of polymeric microspheres to an adhesive system prior to polymerization seems to enhance this behavior, the resultant composition having a unique combination of superior low temperature performance and such desirable mechanical properties as superior compression recovery, high peel strength, improved static shear, and high tensile strength.

[0044] In certain versions of the present subject matter, the dry unexpanded microspheres have a particle size in a range of from 10 to 16 microns. An example of a particular type of commercially available microspheres which can be used in the present subject matter is EXPANCEL 031 DU 40 from AkzoNobel.

[0045] Although the various adhesive compositions can utilize varying weight proportions of the expanda ble microspheres, a typical weight proportion is from 0.1% to 12% and more particularly from 1% to 6% of microspheres (by dry weight) based upon the weight of the adhesive. In certain versions, the microspheres can be used at a weight proportion of 1% to 10%. Lower proportions are contemplated.

[0046] Incorporation of expandable microspheres in the substrate-facing adhesive improves removability of the adhesives, improves gap-filling characteristics of the adhesives, and produces a more compressible and conformable adhesive layer. The resulting substrate-facing adhesive containing expanda ble microspheres exhibits excellent adhesion strength to, and removability from, substrates such as drywall or other residential interior surfaces.

Article-Facing Adhesive

[0047] The article-facing adhesive is generally a removable adhesive. However, the present subject matter includes the use of one or more permanent adhesives as the article-facing adhesive. In many embodiments of the present subject matter, the article-facing adhesive comprises one or more rubber elastomers and tackifier(s) as previously described herein. The article-facing adhesive may optionally comprise one or more fillers as described herein. The present subject matter also includes versions in which the article-facing adhesive is free of fillers.

[0048] Alternatively, the article-facing adhesive may be a high molecular weight crosslinked acrylic adhesive. An example of a commercially available adhesive suitable for certain versions of the present subject matter is HPA 1902, from Avery Performance Polymers of Painesville, Ohio.

[0049] In certain versions of the present subject matter, the article-facing adhesive and the substrate-facing adhesive exhibit particular tack levels relative to one another. That is, in certain versions the adhesion level of the article-facing adhesive is greater than the adhesion level of the substrate-facing adhesive. And, in other versions of the subject matter, the adhesion level of the substrate-facing adhesive is greater than the adhesion level of the article-facing adhesive.

Polymeric Carrier [0050] The articles of the present subject matter also comprise a polymeric carrier or film. As previously described, the polymeric carrier is disposed between layers or regions of the substrate-facing adhesive and the article-facing adhesive. The carrier can be transparent, translucent, or opaque. In certain versions of the present subject matter, the polymeric carrier is in the form of a polyethylene terephthalate (PET) film.

[0051] Carrier films of the present subject matter generally have a thickness of greater than about 1 mil, and more particularly greater than 2 mils or more. A non-limiting maximum thickness for the carrier is about 10 mils. In another embodiment, a carrier film may also be formed from multiple layers of PET. Thin PET layers by themselves may not be able to withstand mechanical forces in certain end use applications which can lead to cracking of the PET film.

[0052] Opacification of the carrier film may be desirable in certain versions of the subject matter. A variety of additives, in combination or alone, may be used to opacify the carrier film, including inorganics such as CaC0₃, ZnO, BaS0₄ or Ti0₂. In certain versions of the present subject matter, it may be preferred to use additives that do not induce excessive micro-voiding within the carrier film. By micro-voiding it is meant that small voids or cavities can form within the film. This micro-voiding can contribute to the opacity of the film but may also weaken the film. If excessive, micro-voiding can contribute to exfoliation of the film during environmental aging. Exfoliation means that the carrier film fails within itself through a cohesive mechanism wherein layers or pieces of the film are readily removed from the carrier film. The extent of micro-voiding can also be affected by the carrier film manufacturing conditions, molecular orientation, heat set temperatures and use of lower molecular weight polymers, all of which can render the carrier film more susceptible to exfoliation.

[0053] In certain versions of the present subject matter, a preferred additive for opacifying the carrier film is Ti0₂. As previously noted, BaS0₄ can also be used to opacify the film, but under certain conditions and/or levels it can contribute to exfoliation of the carrier film. In certain versions of the present subject matter in which the carrier is opaque, the carrier film is at least 50% opaque and typically contains at least 5% by weight of an additive with levels up to 10% or more often being employed.

[0054] Opacifying additives can typically be added via commercially obtained concentrates, or compounded via methods well known in the art. Alternatively, they can be added to the carrier during polymerization. [0055] However, it will be appreciated that the present subject matter utilizes polymeric carriers that are transparent or substantially so. Transparent carriers are not visibly apparent and may promote the aesthetic and design aspects of the various articles of the present subject matter.

[0056] In certain versions of the present subject matter, one or both faces of the polymeric carrier are treated. Treatments can include corona treatment, plasma treatment, flame treatment, application of print or adhesive receptive coatings such as primers, and combinations thereof. As previously noted, coloring and/or opacifying treatments may be performed upon one or both faces of the carrier, such as to produce a transparent or clear carrier and white opaque carrier.

Structural Member

[0057] The present subject matter articles also include one or more structural member(s) that are adhered to the article-facing adhesive. The structural members can be provided in a wide array of different configurations, shapes, and sizes. Representative non-limiting examples include hooks, hangers, posts, mounting plates, brackets, buttons, clasps, and outwardly extending members including shelfs, supports, and anchors. The structural members can also include combinations of these components. It will be appreciated that although certain versions of the present subject matter are described as providing wall mounted hooks, the subject matter is applicable to an extensive number of other applications.

[0058] Figures 1-3 schematically illustrate a removable film tape article in accordance with the present subject matter. Figure 1 illustrates a removable article 1 in accordance with the present subject matter. Specifically, the article 1 comprises a polymeric carrier 20 defining a first face 22 and an oppositely directed second face 24. The article 1 also comprises a layer of a substrate-facing adhesive 10 disposed along and typically in contact with the first face 22 of the carrier 20. The substrate-facing adhesive 10 defines a first face 12 and an oppositely directed second face 14. The article 1 additionally comprises a layer of an article-facing adhesive 30 disposed along and typically in contact with the second face 24 of the carrier 20. The adhesive 30 defines a first face 32 and an oppositely directed second face 34. And, the article 1 also comprises a structural member 40. In the particular embodiment depicted in Figure 1, the structural member 40 defines a first face 42 which is disposed along and typically in contact with the second face 34 of the adhesive layer 30. The structural member 40 also defines a second face 44, generally oppositely directed from the first face 42. The member 40 in the version shown in Figure 1, includes a hook member 46. [0059] The article 1 also includes a pull tab. The pull tab may be incorporated or provided by the article in a variety of fashions. In one embodiment, a pull ta b is provided by an outwardly extending portion of the carrier film 20, shown in Figure 1 as portion A. The outwardly extending portion A extends beyond on edge or peripheral region of at least one of (i) the substrate-facing adhesive 10, (ii) the article-facing adhesive 30, and/or (iii) the structural member 40. In certain versions of the present subject matter, the pull tab portion A extends beyond the edge or peripheral regions of all of (i)-(iii). In particular versions of the present subject matter, in which orientation of the article may be important such as for hook-type articles having a particular intended orientation, the pull tab A extends in a downward direction from the noted edges and peripheral regions.

[0060] Figure 2 is another schematic view of a partial cross section of the article 1. The various components, i.e., 10, 20, 30, and 40, are depicted in an assembled configuration in contrast to the exploded depiction in Figure 1. Figure 2 further reveals a downward extension of the pull tab portion A of the carrier film 20 beyond the edges of the adhesive layers 10 and 30 and the structural member 40.

[0061] Figure 3 is another schematic partial cross section of the article 1 adhered to a wall 5. Figure 3 illustrates a removal operation of the article 1 from the wall by pulling the pull tab portion of the carrier film 20. Typically, separation of the substrate-facing adhesive layer 10 and the wall is promoted by pulling the carrier film 20 in the direction C, which is at an angle B from the wall 5. The angle B can be from about 1° to 90° or more. Typically, relatively large angles, e.g., angle B, may be precluded due to obstruction from lower regions of the structural member 40. However, for many versions of the present subject matter it is contemplated that excellent removal of an article from a substrate occurs at B angles within a range of 60° to 120°.

Release Liner

[0062] An optional release liner or layer may also be provided. The liner covers or is disposed on an otherwise exposed face of the substrate-facing adhesive. The liner protects the adhesive face prior to use. Upon application of the article to a substrate of interest, a user removes the liner from the adhesive face or layer.

[0063] The release liner is composed of a release coating and a liner. The liner may be any useful liner which provides the strength and properties needed to provide support and release properties. The liner may be any liner known to be useful such as paper or polymeric film liners. In one embodiment, the liner has lay flat properties. The liner has, in one case, a machine glaze or finish. [0064] The release coating of the release liner provides a releasable bond with the adhesive. The release coating may be any composition which provides the necessary releasable bond strength.

[0065] In one embodiment, the release coating is a silicone release coating. The release coating is prepared by curing silicone polymers in the presence of a control release agent.

[0066] The release coating, in one embodiment, is prepared with a cross linking agent. The cross linking agent is a reactive polysiloxane, such as a polydialkyl or polyhydroalkyl siloxane.

[0067] The components of the silicone release coating are typically present in an amount up to about 40%, or preferably from about 50% to about 75% by weight of the solvent release coating. The polysiloxane is generally present in an amount of at least 21%, preferably from about 25% to about 50% by weight. The cross linking agent is present in an amount less than about 10% by weight.

[0068] The release coating may be applied in a solvent, solvent-less or emulsion form. The release coating may be cured by any known curing process, e.g. thermal, radiation, etc., to form the release coating. The curing may be catalyzed by silicone soluble complexed compounds of Group VIII transition metals, such as platinum.

[0069] An example of a commercially available control release agent is GE SS-4335, a silicone control release agent in unreactive solvent. An example of a useful polysiloxane is GE SS-4331, a vinyl terminated polydimethyl siloxane. An example of a useful cross linking agent is GE SS-4300C, a polymethyl vinyl siloxane. An example of the catalyst is SS-8010 catalyst in toluene. These materials are available commercially from General Electric Company's Silicone Products Division. Similar silicone products are available under the Tradename SYL-OFF from Dow Corning Corporation.

[0070] The present subject matter also relates to methods of treating one or more adhesive layers of the articles described herein. Treating may involve at least partially crosslinking and/or curing of one or more adhesive layer(s) to selectively modify one or more of its characteristics or properties such as tack or adhesive strength. For example, such treating can be performed to increase cohesive strength of a rubber based adhesive, reduce adhesion, and thus improve removability, and/or increase shear resistance. In certain embodiments, the treatment methods involve exposing an adhesive layer of an article to electron beam radiation. Although the present subject matter includes a wide array of treatment methods using a variety of adhesive compositions, in certain embodiments it may be beneficial to utilize a rubber based adhesive and expose the adhesive to electron beam radiation to alter its properties. The treatment methods are typically performed during and/or after manufacturing of the adhesive article and prior to use, such as use by a consumer or other user. Examples

[0071] In order to further assess the performance of articles according to the present subject matter, a series of evaluations were performed as follows:

Example 1

[0072] Various adhesive samples were prepared to evaluate suitability of an adhesive for use as a substrate-facing adhesive as described herein. The adhesive formulation for the samples was as follows:

Table 1: Adhesive Formulation for Samples

*These weight percentages are based upon the weight of the PSA adhesive.

[0073] 180° peel adhesion was measured using the formed adhesive samples. 180° peel adhesion was measured in accordance with PSTC-1 using 2 mil PET strips. Table 2 summarizes the results of this testing.

Table 2: 180° Peel Testing Results

[0074] Table 3 summarizes the parameters used during the 180° peel measurements. Table 3: 180° Peel Measurement Parameters

[0075] Loop tack was measured using the formed adhesive samples. Loop tack was measured using sample strips that were 1 inch wide by 8 inches in length using stainless steel as the substrate at a draw rate of 20 inches/minute, according to Loop Tack Test L-1B2, using an Instron Universal Tester. Loop tack values were taken to be the highest measured adhesion value observed during the test. The results are set forth in Table 4, below.

Table 4: Loop Tack Testing Results

[0076] Table 5 summarizes the parameters used during the loop tack measurements.

Table 5: Loop Tack Measurement Parameters

A SIS-based rubber adhesive was prepared using the formulation set forth below in Tabl Table 6: Formulation of Example 2 Adhesive

[0078] The adhesive was then filed with a carbon black filler dispersed in resin and with calcium carbonate in the following proportions as noted in Table 7.

Table 7: Samples A-G of Example 2

[0079] Tables 8 and 9 present the results of those 180° peel measurements.

Table 8: 180° Peel Testing Results After 15 Minutes Dwell

Table 9: 180° Peel Testing Results After 24 Hours Dwell

[0080] Table 10 summarizes the parameters used during the testing summarized in Tables 8 and 9. Table 10: 180° Peel Measurement After Dwell Parameters

[0081] Additional Loop tack measurements were made of the samples. These results are set forth below in Tables 11 and 12.

Table 11: Loop Tack Testing Results

Table 12: Loop Tack Measurement Parameters

[0082] Static shear measurements were also performed upon the samples. In the static shear testing, samples were cut into 0.5 inch by 1 inch strips (Table 13) and 1 inch by 1 inch strips (Table 14). The test strips were applied to stainless steel test panels. The samples were pressed against the panels using a rubber faced roller, rolling back and forth. After a dwell time of 2 hours under standard laboratory conditions, the test panels with the samples adhered to them were placed in a vertical or near vertical orientation. A load of 2,250 grams was attached to the end of the samples. The time in minutes for the sample to fail was measured by a timer. The results are provided in Tables 13 and 14 as follows.

Table 13: Static Shear For 0.5 x 1.0 Inch Samples

[0083] Table 15 summarizes the static shear measurement parameters for the testing of Tables 13 and 14.

Table 15: Static Shear Measurement Parameters

Example 3

[0084] In another series of evaluations, adhesive compositions containing expanda ble microspheres were prepared. Samples of the resulting compositions then subjected to testing to indicate adhesion strength.

[0085] Specifically samples were formed from the adhesive formulation set forth in Table 16 as follows:

Table 16: Adhesive Formulation for Samples

"Weight percentages referring to dry weight of microspheres and based upon weight of adhesive.

[0086] Samples (1.2 inches by 3 inches) were prepared from the adhesive formulation noted in Table 16 and deposited on PET carrier films. The adhesive was deposited at a coating thickness of about 5 mils. The samples were maintained at 120° F for 2 hours. After such dwelling, the samples were adhered to either a flat painted drywall substrate or a gloss painted drywall substrate (all substrates vertically oriented). A load of 5.5 pounds was attached to each sample.

[0087] The removal force required to remove the samples from the drywall substrate was then measured. That is, the amount of force necessary to remove the sample and load by pulling the carrier at an angle of 90° from the drywall substrate at a rate of 12 inches/minute was measured. Both average loads and peak loads were measured and are set forth below in Table 17. Table 17: Removal Forces for Samples

Example 4

[0088] A standard tackified SIS rubber adhesive formulation was filled with 0 to 10% expand microspheres per dry mass and samples were labeled E0 to E10 in regard to percent loading.

[0089] The samples were subjected to 180° adhesion testing as summarized in Tables 18-20. Table 18: 180° Adhesion Parameters

Table 19: Initial 180° Adhesion Results

Table 20: 24 Hour 180° Adhesion Results

[0090] The samples were also subjected to loop tack evaluations, which are summarized in Tables 21-22.

Table 21: Loop Tack Parameters

Table 22: Loop Tack Results

[0091] The samples were also su bjected to static shear evaluations, which are summarized in Tables 23-24. Table 23: Static Shear Parameters

Table 24: Static Shear Results

Example 5

[0092] A rubber adhesive was prepared utilizing SIS rubber block copolymer and hydrocarbon resin tackifier. The adhesive was then loaded with sulfur-functional photoinitiator, 031-DU 40 EXPANCEL expanding microspheres, and carbon black dispersed in STAYBELITE ester resin. The samples were coated using comma coating technology and directly deposited on PET carrier with an uncoated filmic edge exposed. The adhesive was then coated on a second side with a tackified acrylic adhesive with a second uncoated filmic edge exposed to facilitate removal.

[0093] Table 25 summarizes the composition of Samples A-H used in this example.

Table 25: Samples A-H of Example 5

Sample Rubber to Resin Photo-initiator (%) Microsphere Carbon Black Filler Weight Ratio Loading (%) (%)

F 1.66 0.9 3.0 0

G 1.66 0 4.0 0

H 1.66 0.9 4.0 0

[0094] The samples were subjected to 90° Adhesion testing using various substrates, and with 15 minutes or 24 hours dwell, at room temperature (RT). Tables 26-29 summarize the results of these evaluations.

Table 26: 90° Adhesion Parameters

Table 27: 90° Adhesion, Stainless Stee

Table 29: 90° Adhesion, Flat Drywall

[0095] The samples were also subjected to Loop Tack testing. Tables 30-31 summarize these evaluations.

Table 30: Loop Tack Parameters

Table 31: Loop Tack Results

[0096] The samples were also subjected to static shear evaluations, as summarized in Tables 32- 33. Table 32: Static Shear Parameters

Table 33: Static Shear Results

[0097] Many other benefits will no doubt become apparent from future application and development of this technology.

[0098] All patents, published applications, and articles noted herein are hereby incorporated by reference in their entirety.

[0099] As described hereina bove, the present subject matter solves many problems associated with previous strategies, systems and/or devices. However, it will be appreciated that various changes in the details, materials and arrangements of components, which have been herein described and illustrated in order to explain the nature of the present subject matter, may be made by those skilled in the art without departing from the principle and scope of the claimed subject matter, as expressed in the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A removable article comprising:

a carrier defining a first face and an oppositely directed second face;

a substrate-facing adhesive disposed on the first face of the carrier;

an article-facing adhesive disposed on the second face of the carrier; and a structural member disposed on and contacting the article-facing adhesive;

wherein the carrier includes a carrier portion extending beyond an edge of at least one of the substrate-facing adhesive, the article-facing adhesive, and the structural member.

2. The article of claim 1 wherein the carrier includes a polymeric film.

3. The article of claim 2 wherein the polymeric film is polyethylene terephthalate (PET).

4. The article of any one of claims 1-3 wherein the carrier is transparent.

5. The article of any one of claims 1-3 wherein the carrier is translucent.

6. The article of any one of claims 1-3 wherein the carrier is opaque.

7. The article of any one of claims 1-6 wherein the substrate-facing adhesive is a removable adhesive.

8. The article of any one of claims 1-6 wherein the substrate-facing adhesive includes a rubber based adhesive and at least one tackifier.

9. The article of claim 8 wherein the substrate-facing adhesive also includes at least one filler.

10. The article of claim 9 wherein the filler is present in a weight proportion of from 5% to 40% based upon the weight of the adhesive.

11. The article of any one of claims 8-10 wherein the adhesive also includes a solvent.

12. The article of any one of claims 1-11 wherein the article-facing adhesive is a removable adhesive.

13. The article of any one of claims 1-11 wherein the article-facing adhesive includes a rubber based adhesive and at least one tackifier.

14. The article of claim 13 wherein the article-facing adhesive also includes at least one filler.

15. The article of any one of claims 1-11 wherein the article-facing adhesive is a high molecular weight crosslinked acrylic adhesive.

16. The article of any one of claims 1-15 wherein the substrate-facing adhesive exhibits a lower tackiness than the article-facing adhesive.

17. The article of any one of claims 1-16 wherein the structural member is selected from the group consisting of a hook, a hanger, a post, a mounting plate, a bracket, a button, a clasp, a shelf, a support, an anchor, and combinations thereof.

18. The article of any one of claims 1-17 wherein the substrate-facing adhesive comprises expanda ble microspheres.

19. The article of claim 18 wherein the expandable microspheres are present in the adhesive at a weight proportion of from 0.1% to 12%.

20. The article of claim 19 wherein the expandable microspheres are present at a weight proportion of from 1% to 10%.

21. The article of any one of claims 18-20 wherein prior to expansion, the microspheres have a particle size in a range of from 10 to 16 microns.

22. The article of any one of claims 1-21 wherein at least one of the substrate-facing adhesive and the article-facing adhesive can be cured or crosslinked by exposure to electron beam radiation.

23. The article of any one of claims 1-22 wherein at least one of the substrate-facing adhesive and the article-facing adhesive includes a photoinitiator.

24. The article of any one of claims 1-23 wherein at least one of the su bstrate-facing adhesive and the article-facing adhesive includes a rubber based adhesive and is cured by exposure to electron beam radiation.

25. A removable article comprising:

a polymeric carrier defining a first face and an oppositely directed second face;

a substrate-facing adhesive disposed on the first face of the carrier;

wherein the substrate-facing adhesive exhibits a lower tackiness than the article-facing adhesive.

26. The article of claim 25 wherein the carrier includes a polymeric film.

27. The article of claim 26 wherein the polymeric film is polyethylene terephthalate (PET).

28. The article of any one of claims 25-27 wherein the carrier is transparent.

29. The article of any one of claims 25-27 wherein the carrier is translucent.

30. The article of any one of claims 25-27 wherein the carrier is opaque.

31. The article of any one of claims 25-30 wherein the su bstrate-facing adhesive is a removable adhesive.

32. The article of any one of claims 25-30 wherein the substrate-facing adhesive includes a rubber based adhesive and at least one tackifier.

33. The article of claim 32 wherein the substrate-facing adhesive also includes at least one filler.

34. The article of claim 33 wherein the filler is present in a weight proportion of from 5% to 40% based upon the weight of the adhesive.

35. The article of any one of claims 32-34 wherein the adhesive also includes a solvent.

36. The article of any one of claims 25-35 wherein the article-facing adhesive is a removable adhesive.

37. The article of any one of claims 25-35 wherein the article-facing adhesive includes a rubber based adhesive and at least one tackifier.

38. The article of claim 37 wherein the article-facing adhesive also includes at least one filler.

39. The article of any one of claims 25-35 wherein the article-facing adhesive is a high molecular weight crosslinked acrylic adhesive.

40. The article of any one of claims 25-39 wherein the carrier includes a carrier portion extending beyond an edge of at least one of the substrate-facing adhesive, the article-facing adhesive, and the structural member.

41. The article of any one of claims 25-40 wherein the structural member is selected from the group consisting of a hook, a hanger, a post, a mounting plate, a bracket, a button, a clasp, a shelf, a support, an anchor, and combinations thereof.

42. The article of any one of claims 25-41 wherein the substrate-facing adhesive comprises expanda ble microspheres.

43. The article of claim 42 wherein the expandable microspheres are present in the adhesive at a weight proportion of from 0.1% to 12%.

44. The article of claim 43 wherein the expandable microspheres are present at a weight proportion of from 2% to 10%.

45. The article of any one of claims 42-44 wherein prior to expansion, the microspheres have a particle size in a range of from 10 to 16 microns.

46. The article of any one of claims 25-45 wherein at least one of the substrate-facing adhesive and the article-facing adhesive can be cured or crosslinked by exposure to electron beam radiation.

47. The article of any one of claims 25-46 wherein at least one of the substrate-facing adhesive and the article-facing adhesive includes a photoinitiator.

48. The article of any one of claims 25-47 wherein at least one of the substrate-facing adhesive and the article-facing adhesive includes a rubber based adhesive and is cured by exposure to electron beam radiation.

49. A method of treating an adhesive article having a carrier defining a first face and an oppositely directed second face, a substrate-facing adhesive disposed on the fist face of the carrier, an article-facing adhesive disposed on the second face of the carrier, and a structural member disposed on and contacting the article-facing adhesive, the method comprising: exposing at least one of the substrate-facing adhesive and the article-facing adhesive to electron beam radiation.

50. The method of claim 49 wherein the substrate-facing adhesive exhibits a lower tackiness than the article-facing adhesive.

51. The method of any one of claims 49-50 wherein the adhesive exposed to electron beam radiation is a rubber based adhesive.

52. The method of any one of claims 49-51 wherein the adhesive exposed to electron beam radiation includes at least one photoinitiator.