WO2002090206A1 - A packaging laminate for a retortable packaging container - Google Patents

A packaging laminate for a retortable packaging container Download PDF

Info

Publication number
WO2002090206A1
WO2002090206A1 PCT/SE2002/000874 SE0200874W WO02090206A1 WO 2002090206 A1 WO2002090206 A1 WO 2002090206A1 SE 0200874 W SE0200874 W SE 0200874W WO 02090206 A1 WO02090206 A1 WO 02090206A1
Authority
WO
WIPO (PCT)
Prior art keywords
paper
packaging laminate
alkyl ketene
paperboard
packaging
Prior art date
Application number
PCT/SE2002/000874
Other languages
French (fr)
Inventor
Lars Sickert
Per Floberg
Original Assignee
Tetra Laval Holdings & Finance S A
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tetra Laval Holdings & Finance S A filed Critical Tetra Laval Holdings & Finance S A
Priority to MXPA03010147A priority Critical patent/MXPA03010147A/en
Priority to AU2002306037A priority patent/AU2002306037B2/en
Priority to CA002446548A priority patent/CA2446548A1/en
Priority to US10/477,123 priority patent/US20040170781A1/en
Priority to EP02733656A priority patent/EP1401726A1/en
Priority to JP2002587298A priority patent/JP2005508800A/en
Publication of WO2002090206A1 publication Critical patent/WO2002090206A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B27/10—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of paper or cardboard
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B29/00—Layered products comprising a layer of paper or cardboard
    • B32B29/06—Layered products comprising a layer of paper or cardboard specially treated, e.g. surfaced, parchmentised
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B3/00—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar form; Layered products having particular features of form
    • B32B3/02—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar form; Layered products having particular features of form characterised by features of form at particular places, e.g. in edge regions
    • B32B3/04—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar form; Layered products having particular features of form characterised by features of form at particular places, e.g. in edge regions characterised by at least one layer folded at the edge, e.g. over another layer ; characterised by at least one layer enveloping or enclosing a material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/04—Interconnection of layers
    • B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/16—Sizing or water-repelling agents
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
    • D21H27/10—Packing paper
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2255/00—Coating on the layer surface
    • B32B2255/12—Coating on the layer surface on paper layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2255/00—Coating on the layer surface
    • B32B2255/26—Polymeric coating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/70—Other properties
    • B32B2307/724—Permeability to gases, adsorption
    • B32B2307/7242—Non-permeable
    • B32B2307/7244—Oxygen barrier
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/70—Other properties
    • B32B2307/73—Hydrophobic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2317/00—Animal or vegetable based
    • B32B2317/12—Paper, e.g. cardboard
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00—Polyalkenes
    • B32B2323/04—Polyethylene
    • B32B2323/043—HDPE, i.e. high density polyethylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00—Polyalkenes
    • B32B2323/04—Polyethylene
    • B32B2323/046—LDPE, i.e. low density polyethylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00—Polyalkenes
    • B32B2323/10—Polypropylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2367/00—Polyesters, e.g. PET, i.e. polyethylene terephthalate
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2439/00—Containers; Receptacles
    • B32B2439/70—Food packaging
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/03—Non-macromolecular organic compounds
    • D21H17/05—Non-macromolecular organic compounds containing elements other than carbon and hydrogen only
    • D21H17/17—Ketenes, e.g. ketene dimers
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H19/00—Coated paper; Coating material
    • D21H19/80—Paper comprising more than one coating
    • D21H19/84—Paper comprising more than one coating on both sides of the substrate
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/13—Hollow or container type article [e.g., tube, vase, etc.]
    • Y10T428/1303—Paper containing [e.g., paperboard, cardboard, fiberboard, etc.]

Definitions

  • the present invention relates to a packaging laminate comprising a base layer of paper or paperboard for a retortable packaging container.
  • a packaging laminate of the type which is described above is known from int.al. international patent application carrying publication number WO97/02140.
  • the prior art packaging laminate has a rigid, but foldable base or core layer of paper or paperboard and outer, liquid-tight coatings of a heat resistant plastic on both sides of the base layer. Between the base layer and one of the two outer plastic coatings, there may moreover be provided a gas barrier, e.g. an aluminium foil, in order to impart to the packaging laminate tightness properties also against gases, in particular oxygen gas.
  • finished packaging containers are produced with the aid of modern packing and filling machines of the type which, either from a web or from prefabricated blanks of the packaging laminate, both form, fill and seal finished packages.
  • a blank a packaging container is produced in that the blank is first formed into a tubular container capsule in that both longitudinal edges of the blank are folded towards and permanently united with one another by thermosealing in a so-called overlap joint which extends all the way between both open ends of the tubular container capsule.
  • the one end of the container capsule is thereafter given a substantially planar end closure (bottom) by fold forming and thermosealing of adjacent end panels of the container capsule.
  • the thus end sealed (provided with a bottom) container capsule is filled with the desired contents, e.g. a food, through its other, open end which, after the filling operation, is given a similarly substantially planar end closure (top) by a final fold forming and thermosealing of the corresponding end panels of the filled container capsule.
  • desired contents e.g. a food
  • a shelf-life extending heat treatment of a packed food is generally carried out in a retort which is an apparatus comprising a closed treatment chamber in which both temperature and pressure may be regulated and controlled during the heat treatment.
  • such a heat treatment or retorting is carried out in the manner and under the conditions which are described in greater detail in international patent application carrying publication number WO98/16431, which is hereby incorporated as reference.
  • Filled packaging containers are placed in the treatment space of the retort, whereafter a gaseous heating medium, e.g. hot steam, is caused to flow in contact with the outer walls of the packaging containers for heating the packed food to a previously selected treatment temperature which generally lies within the range of between 70 and 130° C.
  • the packed food is kept at this temperature for a predetermined sufficiently long time so as to ensure as good as total thermal destruction of the microorganisms present in the food.
  • the treated food is thereafter cooled with a coolant, e.g. cold water, down to a temperature close to or somewhat above the ambient temperature, i.e. 25 - 30° C, whereafter the treatment is discontinued and the packaging containers are removed from the retort.
  • a coolant e.g. cold water
  • Different foods require different forms of treatment in order to achieve complete sterility by a heat treatment in a retort.
  • more extensive heat treatment is required, i.e. more elevated treatment temperature and / or longer treatment time than for other foods which only require a shorter stay time at a relatively low treatment temperature in order to achieve the contemplated sterility.
  • a packaging container of the above-described known packaging laminate is generally sufficiently mechanically strong and stable to withstand such a relatively gentle or less extensive heat treatment, but, on the other hand, it not seldom occurs that the prior art packaging containers are damaged or destroyed and even become totally unusable if the heat treatment is carried out at a relatively elevated treatment temperature and / or during a relatively lengthy treatment time which may occasionally be necessary to ensure complete and total sterility in certain types of foods.
  • One object of the present invention is therefore to obviate the above-discussed drawbacks in connection with the prior art technology.
  • Another object of the present invention is to provide a packaging laminate for a packaging container which reliably withstands a heat treatment in a retort without the risk of being damaged because of penetrating moisture or liquid, even if the heat treatment is carried out at an elevated treatment temperature and / or during a lengthy treatment time in a retort.
  • a packaging laminate is thus provided for a retortable packaging container including a paper or paperboard layer which has been rendered hydrophobic by stock sizing.
  • the packaging laminate according to the present invention requires neither extra chemical nor mechanical agents in order to protect the exposed incision edges. Consequently, the packaging laminate according to the present invention may be produced in a simple manner employing already existing conversion equipment without the employment of extra operational steps and associated extra equipment during the production of the packaging laminate.
  • the paper or paperboard layer rendered hydrophobic may, according to the present invention, be produced by stock sizing by means of alkyl ketene dimers dispersed or emulsified in aqueous solution.
  • alkyl ketene dimers dispersed or emulsified in aqueous solution.
  • such aqueous dispersions or emulsions contain alkyl ketene dimers with 16 - 22 carbon atoms in their fat tail.
  • the packaging laminate includes a paper or paperboard layer which has been rendered hydrophobic by means of an aqueous dispersion or emulsion of an alkyl ketene dimer which has a fat tail of 18 carbon atoms.
  • An aqueous dispersion or emulsion of an alkyl ketene dimer with 18 carbon atoms makes possible not only a high absorption of the alkyl ketene dimer in the paper pulp and thereby a high closure of the pores (hydrophobic) in the produced paper or paperboard layer, but this desired high absorption may be carried out without impeding the subsequent handling and processing of the paper pulp in the paper machine.
  • the paper or paperboard layer in the packaging laminate according to the present invention includes an alkyl ketene dimer in a quantity which is greater than approx. 0.25 weight %, calculated on the dry weight of the paper or paperboard layer.
  • the quantity of alkyl ketene dimer should preferably be greater than 2.5 kg per tonne of paper or paperboard, but should not be greater than approx. 4 kg which is a maximum permitted quantity for use in food contexts.
  • Fig. 1 schematically shows a cross section of a packaging laminate in its simplest embodiment according to the present invention.
  • Fig. 2 shows the packaging laminate according to one preferred practical embodiment of the present invention.
  • Fig. 1 thus schematically shows a cross section of a packaging laminate in its simplest embodiment of the present invention.
  • the packaging laminate with the generic reference numeral 10 includes a base or core layer 11 of paper or paperboard and outer, liquid-tight coatings 12 and 13 of a thermosealable plastic on both sides of the base layer 11.
  • the base layer 11 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer or a mixture of alkyl ketene dimers of varying numbers of carbon atoms in their respective fat tails, preferably between 16 and 22 carbon atoms.
  • the base layer 11 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer with 18 carbon atoms in its fat tail.
  • the quantity of alkyl ketene dimers in the base layer 11 may vary, but is preferably at least approx. 0.25 weight % calculated on the dry weight of the base layer. In such cases where the packaging laminate 10 according to the present invention is intended to be employed in connection with a food, the quantity of alkyl ketene dimer should not, however, exceed 0.4 weight % calculated on the dry weight of the base layer 11. Expressed otherwise, the quantity of alkyl ketene dimer is preferably 2.5 - 4 kg/tonne of paper or paperboard in the dry base layer 11.
  • the material in the two outer liquid-tight coatings of plastic 12 and 13 is preferably a thermosealable plastic in order to make for a rational production of finished retortable packaging containers.
  • thermosealable plastics for use in the two outer liquid-tight coatings 12 and 13 include, but are not limited to, polyethylene (PE), polypropylene (PP), polyester (PET) and copolymers thereof.
  • PE polyethylene
  • PP polypropylene
  • PET polyester
  • copolymers thereof examples of a usable polythene plastic may be a high density polyethylene (HDPE) or a linear low density polyethylene (LLDPE), and example of a usable polyester plastic may be an amorphous polyester (APET).
  • HDPE high density polyethylene
  • LLDPE linear low density polyethylene
  • APET amorphous polyester
  • Fig. 2 shows a schematic cross section of a packaging laminate according to one preferred embodiment of the present invention.
  • the packaging laminate with the generic reference numeral 20 has a base layer 21 of paper or paperboard and outer, liquid-tight coatings 22 and 23 on both sides of the base layer 21.
  • the packaging laminate 20 further displays a gas barrier 24 between the base layer 21 and one of the two outer liquid-tight coatings 22.
  • the outer, liquid-tight coating 23 on the other side of the base layer 21 may display decorative art work 27 of a suitable printing ink which in its turn is protected by a transparent layer 28, applied above the decorative art work 27 and consisting of suitable lacquer or other agent so as to protect the decorative art work 27 against attack from outside.
  • the base layer 21 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer or a mixture of alkyl ketene dimers with a varying number of carbon atoms in their respective fat tails, preferably between 16 and 22 carbon atoms.
  • the base layer 21 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer with 18 carbon atoms in its fat tail.
  • the quantity of alkyl ketene dimer in the base layer 21 may vary, but is preferably at least approx. 0.25 weight % calculated on the dry weight of the base layer 21. In such cases where the packaging laminate 20 according to the present invention is intended to be employed in connection with foods, the quantity of alkyl ketene dimer should, however, not be greater than approx. 0.4 weight % calculated on the dry weight of the base layer 21. Expressed otherwise, the quantity of alkyl ketene dimer is preferably 2.5 - 4 kg/tonne of paper or paperboard in the dry base layer 21.
  • the outer, liquid-tight coating 23 may be a plastic which is selected from the group essentially comprising polyethylene (PE), polypropylene (PP) and polyester (PET) or mixtures thereof.
  • PE polyethylene
  • PP polypropylene
  • PET polyester
  • usable polyethylene plastic may be high density polyethylene (HDPE) or linear low density polyethylene (LLDPE)
  • HDPE high density polyethylene
  • LLDPE linear low density polyethylene
  • OPP oriented polypropylene
  • APET amorphous polyester
  • the liquid-tight coating 23 consists of a physical or mechanical mixture of polypropylene (PP) and polyethylene (PE) which, in addition to superior tightness properties against liquid, also possesses sufficient moisture and heat resistance to withstand such extreme moisture and temperature stresses as occur in a normal shelf-life extending heat treatment in a retort.
  • An outer coating 23 of a physical or mechanical mixture of polypropylene (PP) and polyethylene (PE) moreover possesses superior printability at the same time as making possible mechanically strong and liquid-tight seals by so-called thermosealing, when the packaging laminate 20 is reformed into a retortable packaging container.
  • the outer, liquid-tight coating 22 may consist of a plastic which is selected from the group essentially comprising polyethylene (PE), polypropylene (PP), polyester (PET) and copolymers thereof.
  • PE polyethylene
  • PP polypropylene
  • PET polyester
  • An example of a usable polyethylene plastic may be a high density polyethylene (HDPE) or a linear low density polyethylene (LLDPE), and an example of a usable polyester plastic may be an amorphous polyester (APET).
  • HDPE high density polyethylene
  • LLDPE linear low density polyethylene
  • APET amorphous polyester
  • the liquid-tight coating 22 consists of a copolymer of propylene and ethylene which is sufficiently moisture and heat resistant to withstand extreme moisture and temperature stresses which occur in a normal shelf-life extending heat treatment in a retort.
  • a coating of a copolymer of propylene and ethylene moreover makes for mechanically strong and liquid-tights seals when the packaging laminate 20 is reformed into a retortable packaging container.
  • the layer 24 serving as gas barrier may consist of an organic or an inorganic material.
  • An example of a usable inorganic material may be a metal foil, e.g. an aluminium foil, or a silica oxide coating produced by plasma deposition, and an example of a suitable organic material may be a so-called barrier polymer, e.g. a copolymer of ethylene and vinyl alcohol (EVOH).
  • the gas barrier 24 is an aluminium foil which, in addition to superior tightness properties against gases, in particular oxygen gas, also makes for sealing of the packaging laminate 20 by induction thermosealing which is a simple, but rapid and efficient sealing technique.
  • a packaging laminate according to the present invention well- functioning retortable packaging containers are produced by fold forming and thermosealing in the previously described manner, packaging containers which may be reliably heat treated at extremely elevated moisture and temperature conditions in a retort, without the packaging laminate delaminating because of moisture and steam which are prevented effectively from penetrating into the base layer, which has been rendered hydrophobic, through exposed incision edges.

Abstract

A packaging laminate (10) for a retortable packaging container of the type which is produced by fold forming and thermosealing of a web or a prefabricated blank of the packaging laminate. The packaging laminate (10) includes a base layer (11) of paper or paperboard which has been rendered hydrophobic by stock sizing. The base layer (11) is preferably rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer or mixture of alkyl ketene dimers with a different number of carbon atoms in their respective fat tails. Most preferably, the base layer (11) is rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer containing 18 carbon atoms in its fat tail. The quantity of alkyl ketene dimers is suitably at least approx. 0.25 weight %, preferably 0.25 - 0.4 weight %, most preferably approx. 0.4 weight %, calculated on the dry weight of the base layer (11).

Description

A PACKAGING LAMINATE FOR A RETORTABLE PACKAGING CONTAINER
TECHNICAL FIELD The present invention relates to a packaging laminate comprising a base layer of paper or paperboard for a retortable packaging container.
BACKGROUND ART
A packaging laminate of the type which is described above is known from int.al. international patent application carrying publication number WO97/02140. The prior art packaging laminate has a rigid, but foldable base or core layer of paper or paperboard and outer, liquid-tight coatings of a heat resistant plastic on both sides of the base layer. Between the base layer and one of the two outer plastic coatings, there may moreover be provided a gas barrier, e.g. an aluminium foil, in order to impart to the packaging laminate tightness properties also against gases, in particular oxygen gas.
Similar packaging laminates are also described in international patent applications numbers WO97/02181 and WO98/18680.
From the prior art packaging laminates, finished packaging containers are produced with the aid of modern packing and filling machines of the type which, either from a web or from prefabricated blanks of the packaging laminate, both form, fill and seal finished packages. From, for example, a blank a packaging container is produced in that the blank is first formed into a tubular container capsule in that both longitudinal edges of the blank are folded towards and permanently united with one another by thermosealing in a so-called overlap joint which extends all the way between both open ends of the tubular container capsule. The one end of the container capsule is thereafter given a substantially planar end closure (bottom) by fold forming and thermosealing of adjacent end panels of the container capsule. The thus end sealed (provided with a bottom) container capsule is filled with the desired contents, e.g. a food, through its other, open end which, after the filling operation, is given a similarly substantially planar end closure (top) by a final fold forming and thermosealing of the corresponding end panels of the filled container capsule.
It has long been known that the shelf life of a food may be extended in that the food is subjected to a heat treatment which is so extensive that bacteria, fungi and other undesirable microorganisms existing in the food are exterminated, neutralised or reduced. In order to achieve complete sterilisation, this heat treatment must be carried out under such conditions that all parts of the treated food are heated to such an elevated level and for such a lengthy period of time as are required to ensure a complete destruction or deactivation of the microorganisms in the food. A shelf-life extending heat treatment of a packed food is generally carried out in a retort which is an apparatus comprising a closed treatment chamber in which both temperature and pressure may be regulated and controlled during the heat treatment. Preferably, such a heat treatment or retorting is carried out in the manner and under the conditions which are described in greater detail in international patent application carrying publication number WO98/16431, which is hereby incorporated as reference. Filled packaging containers are placed in the treatment space of the retort, whereafter a gaseous heating medium, e.g. hot steam, is caused to flow in contact with the outer walls of the packaging containers for heating the packed food to a previously selected treatment temperature which generally lies within the range of between 70 and 130° C. The packed food is kept at this temperature for a predetermined sufficiently long time so as to ensure as good as total thermal destruction of the microorganisms present in the food. The treated food is thereafter cooled with a coolant, e.g. cold water, down to a temperature close to or somewhat above the ambient temperature, i.e. 25 - 30° C, whereafter the treatment is discontinued and the packaging containers are removed from the retort.
Different foods require different forms of treatment in order to achieve complete sterility by a heat treatment in a retort. For certain foods, more extensive heat treatment is required, i.e. more elevated treatment temperature and / or longer treatment time than for other foods which only require a shorter stay time at a relatively low treatment temperature in order to achieve the contemplated sterility. A packaging container of the above-described known packaging laminate is generally sufficiently mechanically strong and stable to withstand such a relatively gentle or less extensive heat treatment, but, on the other hand, it not seldom occurs that the prior art packaging containers are damaged or destroyed and even become totally unusable if the heat treatment is carried out at a relatively elevated treatment temperature and / or during a relatively lengthy treatment time which may occasionally be necessary to ensure complete and total sterility in certain types of foods.
One problem which is often observed in connection with such extreme, severe heat treatment is that liquid or moisture tends to penetrate into the paper or paperboard layer of the packaging container in areas where incision edges of the paper or paperboard layer are more or less freely exposed to the gaseous heating medium, e.g. hot steam. An example of such a particularly moisture and heat- sensitive area of the packaging container is along the freely exposed incision edge which extends all way between both ends of the tubular container capsule, i.e. the top and bottom of the packaging container. This penetration of moisture or liquid may, in particularly serious cases, entail that the packaging wall swells and delaminates and thereby becomes unattractive or wholly unusable for further handling.
Previous attempts to solve the above described problem with moisture and liquid absorbing incision edges have taken as their point of departure to protect or cover these edges either chemically by impregnation with a water-repellent or mechanically by slicing and refolding, as described in international patent application carrying publication number WO98/18680. While both of these prior art methods solve the problem inherent in moisture and liquid penetration, they require at least one extra operation and thereby associated extra equipment during the production of the packaging laminate.
One object of the present invention is therefore to obviate the above-discussed drawbacks in connection with the prior art technology.
Another object of the present invention is to provide a packaging laminate for a packaging container which reliably withstands a heat treatment in a retort without the risk of being damaged because of penetrating moisture or liquid, even if the heat treatment is carried out at an elevated treatment temperature and / or during a lengthy treatment time in a retort.
These and other objects are attained according to the present invention in that the packaging laminate described by way of introduction has been given the characterising feature as set forth in appended claim 1.
Advantages and expedient embodiments of the packaging laminate according to the present invention have further been given the characterising features as set forth in the appended subclaims.
SUMMARY OF THE INVENTION
According to the present invention, a packaging laminate is thus provided for a retortable packaging container including a paper or paperboard layer which has been rendered hydrophobic by stock sizing.
Since a paper or paperboard layer rendered hydrophobic by stock sizing already from the outset has sufficient tightness properties against moisture and liquid, the hydrophobic paper or paperboard layer in the packaging laminate according to the present invention requires neither extra chemical nor mechanical agents in order to protect the exposed incision edges. Consequently, the packaging laminate according to the present invention may be produced in a simple manner employing already existing conversion equipment without the employment of extra operational steps and associated extra equipment during the production of the packaging laminate.
The paper or paperboard layer rendered hydrophobic may, according to the present invention, be produced by stock sizing by means of alkyl ketene dimers dispersed or emulsified in aqueous solution. In practical examples, such aqueous dispersions or emulsions contain alkyl ketene dimers with 16 - 22 carbon atoms in their fat tail.
In a particularly preferred embodiment according to the present invention, the packaging laminate includes a paper or paperboard layer which has been rendered hydrophobic by means of an aqueous dispersion or emulsion of an alkyl ketene dimer which has a fat tail of 18 carbon atoms. An aqueous dispersion or emulsion of an alkyl ketene dimer with 18 carbon atoms makes possible not only a high absorption of the alkyl ketene dimer in the paper pulp and thereby a high closure of the pores (hydrophobic) in the produced paper or paperboard layer, but this desired high absorption may be carried out without impeding the subsequent handling and processing of the paper pulp in the paper machine.
Preferably, the paper or paperboard layer in the packaging laminate according to the present invention includes an alkyl ketene dimer in a quantity which is greater than approx. 0.25 weight %, calculated on the dry weight of the paper or paperboard layer. Expressed otherwise, the quantity of alkyl ketene dimer should preferably be greater than 2.5 kg per tonne of paper or paperboard, but should not be greater than approx. 4 kg which is a maximum permitted quantity for use in food contexts.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The present invention will be described in greater detail hereinbelow, with reference to the accompanying drawing, in which:
Fig. 1 schematically shows a cross section of a packaging laminate in its simplest embodiment according to the present invention; and
Fig. 2 shows the packaging laminate according to one preferred practical embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
Fig. 1 thus schematically shows a cross section of a packaging laminate in its simplest embodiment of the present invention. The packaging laminate with the generic reference numeral 10 includes a base or core layer 11 of paper or paperboard and outer, liquid-tight coatings 12 and 13 of a thermosealable plastic on both sides of the base layer 11.
The base layer 11 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer or a mixture of alkyl ketene dimers of varying numbers of carbon atoms in their respective fat tails, preferably between 16 and 22 carbon atoms. In one particularly preferred embodiment, the base layer 11 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer with 18 carbon atoms in its fat tail.
The quantity of alkyl ketene dimers in the base layer 11 may vary, but is preferably at least approx. 0.25 weight % calculated on the dry weight of the base layer. In such cases where the packaging laminate 10 according to the present invention is intended to be employed in connection with a food, the quantity of alkyl ketene dimer should not, however, exceed 0.4 weight % calculated on the dry weight of the base layer 11. Expressed otherwise, the quantity of alkyl ketene dimer is preferably 2.5 - 4 kg/tonne of paper or paperboard in the dry base layer 11. The material in the two outer liquid-tight coatings of plastic 12 and 13 is preferably a thermosealable plastic in order to make for a rational production of finished retortable packaging containers. Examples of such thermosealable plastics for use in the two outer liquid-tight coatings 12 and 13 include, but are not limited to, polyethylene (PE), polypropylene (PP), polyester (PET) and copolymers thereof. Examples of a usable polythene plastic may be a high density polyethylene (HDPE) or a linear low density polyethylene (LLDPE), and example of a usable polyester plastic may be an amorphous polyester (APET).
Fig. 2 shows a schematic cross section of a packaging laminate according to one preferred embodiment of the present invention. The packaging laminate with the generic reference numeral 20 has a base layer 21 of paper or paperboard and outer, liquid-tight coatings 22 and 23 on both sides of the base layer 21.
The packaging laminate 20 further displays a gas barrier 24 between the base layer 21 and one of the two outer liquid-tight coatings 22.
Between the liquid-tight coating 22 and the gas barrier 24, there is a layer 25 of an adhesive by means of which the liquid-tight coating 22 is bonded to the gas barrier 24.
Between the gas barrier 24 and the base layer 21 there is a layer 26 of a lamination or sealing agent of such a nature that the gas barrier 24 is bonded to the core layer 21 with sufficiently strong and stable bonding strength so as not to be weakened or lost entirely when the packaging laminate 20 is exposed to extremely elevated temperature stresses, i.e. temperatures of up to approx. 130° C or higher. The outer, liquid-tight coating 23 on the other side of the base layer 21 may display decorative art work 27 of a suitable printing ink which in its turn is protected by a transparent layer 28, applied above the decorative art work 27 and consisting of suitable lacquer or other agent so as to protect the decorative art work 27 against attack from outside.
In order to impart to the packaging laminate 20 greater integrity, there is disposed, between the gas barrier 24 and the layer 26 of lamination or sealing agent, a layer 29 of an adhesive by means of which the gas barrier 24 is bonded to the layer 26 of lamination or sealing agent. The base layer 21 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer or a mixture of alkyl ketene dimers with a varying number of carbon atoms in their respective fat tails, preferably between 16 and 22 carbon atoms. In one particularly preferred embodiment, the base layer 21 has been rendered hydrophobic by stock sizing by means of an aqueous dispersion or emulsion of an alkyl ketene dimer with 18 carbon atoms in its fat tail.
The quantity of alkyl ketene dimer in the base layer 21 may vary, but is preferably at least approx. 0.25 weight % calculated on the dry weight of the base layer 21. In such cases where the packaging laminate 20 according to the present invention is intended to be employed in connection with foods, the quantity of alkyl ketene dimer should, however, not be greater than approx. 0.4 weight % calculated on the dry weight of the base layer 21. Expressed otherwise, the quantity of alkyl ketene dimer is preferably 2.5 - 4 kg/tonne of paper or paperboard in the dry base layer 21. The outer, liquid-tight coating 23 may be a plastic which is selected from the group essentially comprising polyethylene (PE), polypropylene (PP) and polyester (PET) or mixtures thereof. Examples of usable polyethylene plastic may be high density polyethylene (HDPE) or linear low density polyethylene (LLDPE), an example of a usable polypropylene plastic may be oriented polypropylene (OPP), and an example of a usable polyester plastic may be amorphous polyester (APET). Preferably, the liquid-tight coating 23 consists of a physical or mechanical mixture of polypropylene (PP) and polyethylene (PE) which, in addition to superior tightness properties against liquid, also possesses sufficient moisture and heat resistance to withstand such extreme moisture and temperature stresses as occur in a normal shelf-life extending heat treatment in a retort. An outer coating 23 of a physical or mechanical mixture of polypropylene (PP) and polyethylene (PE) moreover possesses superior printability at the same time as making possible mechanically strong and liquid-tight seals by so-called thermosealing, when the packaging laminate 20 is reformed into a retortable packaging container. In the same manner, the outer, liquid-tight coating 22 may consist of a plastic which is selected from the group essentially comprising polyethylene (PE), polypropylene (PP), polyester (PET) and copolymers thereof. An example of a usable polyethylene plastic may be a high density polyethylene (HDPE) or a linear low density polyethylene (LLDPE), and an example of a usable polyester plastic may be an amorphous polyester (APET).
Preferably, the liquid-tight coating 22 consists of a copolymer of propylene and ethylene which is sufficiently moisture and heat resistant to withstand extreme moisture and temperature stresses which occur in a normal shelf-life extending heat treatment in a retort. A coating of a copolymer of propylene and ethylene moreover makes for mechanically strong and liquid-tights seals when the packaging laminate 20 is reformed into a retortable packaging container.
The layer 24 serving as gas barrier may consist of an organic or an inorganic material. An example of a usable inorganic material may be a metal foil, e.g. an aluminium foil, or a silica oxide coating produced by plasma deposition, and an example of a suitable organic material may be a so-called barrier polymer, e.g. a copolymer of ethylene and vinyl alcohol (EVOH).
Preferably, the gas barrier 24 is an aluminium foil which, in addition to superior tightness properties against gases, in particular oxygen gas, also makes for sealing of the packaging laminate 20 by induction thermosealing which is a simple, but rapid and efficient sealing technique. From a packaging laminate according to the present invention, well- functioning retortable packaging containers are produced by fold forming and thermosealing in the previously described manner, packaging containers which may be reliably heat treated at extremely elevated moisture and temperature conditions in a retort, without the packaging laminate delaminating because of moisture and steam which are prevented effectively from penetrating into the base layer, which has been rendered hydrophobic, through exposed incision edges.

Claims

WHAT IS CLAIMED IS:
1. A packaging laminate for a retortable packaging container of the type which is produced by fold forming and sealing of a sheet or web-shaped blank of the packaging laminate, the packaging laminate (10; 20) including a base layer (11 ; 21) of paper or paperboard and outer, liquid-tight coatings (12, 13; 22, 23) of thermosealable plastic on both sides of the plastic layer (11 ; 21), characterised in that the paper or paperboard layer is rendered hydrophobic by so-called stock sizing by means of an aqueous suspension or emulsion of an alkyl ketene dimer or mixture of alkyl ketene dimers.
2. The packaging laminate as claimed in claim 1, characterised in that the paper or paperboard layer (11; 21) contains said alkyl ketene dimers in a quantity of at least 0.25 weight %, calculated on the dry weight of the paper or paperboard layer (11 ; 21).
3. The packaging laminate as claimed in claim 1 or 2, characterised in that the paper or paperboard layer (11; 21) contains between 2.5 and 4 kg of alkyl ketene dimers per tonne of paper or paperboard in the dry paper or paperboard layer (11; 21).
4. The packaging laminate as claimed in any of the preceding claims, characterised in that said alkyl ketene dimers are selected from the group essentially comprising alkyl ketene dimers with 16 - 22 carbon atoms in their respective fat tails.
5. The packaging laminate as claimed in claim 4, characterised in that said alkyl ketene dimers have 18 carbon atoms in their fat tail.
6. Use of a paper or paperboard layer ( 11 ; 21) rendered hydrophobic as base layer in a packaging laminate (10; 20) as claimed in any of the preceding claims.
7. A retortable packaging container of a packaging laminate comprising a core layer (11; 21) of paper or paperboard and outer, liquid-tight coatings (12, 13; 22, 23) of thermosealable plastic on both sides of the base layer (11 ; 21), characterised in that the paper or paperboard layer (11; 21) is rendered hydrophobic by so-called stock sizing by means an aqueous suspension or emulsion of at least one alkyl ketene dimer.
PCT/SE2002/000874 2001-05-10 2002-05-07 A packaging laminate for a retortable packaging container WO2002090206A1 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
MXPA03010147A MXPA03010147A (en) 2001-05-10 2002-05-07 A packaging laminate for a retortable packaging container.
AU2002306037A AU2002306037B2 (en) 2001-05-10 2002-05-07 A packaging laminate for a retortable packaging container
CA002446548A CA2446548A1 (en) 2001-05-10 2002-05-07 A packaging laminate for a retortable packaging container
US10/477,123 US20040170781A1 (en) 2001-05-10 2002-05-07 Packaging laminate for a retortable packaging container
EP02733656A EP1401726A1 (en) 2001-05-10 2002-05-07 A packaging laminate for a retortable packaging container
JP2002587298A JP2005508800A (en) 2001-05-10 2002-05-07 Packaging for packaging of retortable packaging containers

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE0101673A SE0101673L (en) 2001-05-10 2001-05-10 Packaging laminate for an autoclavable packaging container
SE0101673-2 2001-05-10

Publications (1)

Publication Number Publication Date
WO2002090206A1 true WO2002090206A1 (en) 2002-11-14

Family

ID=20284083

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE2002/000874 WO2002090206A1 (en) 2001-05-10 2002-05-07 A packaging laminate for a retortable packaging container

Country Status (10)

Country Link
US (1) US20040170781A1 (en)
EP (1) EP1401726A1 (en)
JP (1) JP2005508800A (en)
CN (1) CN1275766C (en)
AU (1) AU2002306037B2 (en)
CA (1) CA2446548A1 (en)
MX (1) MXPA03010147A (en)
RU (1) RU2289535C2 (en)
SE (1) SE0101673L (en)
WO (1) WO2002090206A1 (en)

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003097351A1 (en) * 2002-05-15 2003-11-27 Knut Magne Furuheim A method for manufacturing laminated hd (high-density) paper with good oxygen-barrier properties, and hd paper obtained thereby
WO2004101279A1 (en) * 2003-05-16 2004-11-25 Basf Aktiengesellschaft Packaging material consisting of an at least double-layered composite material for producing containers for packing liquids
WO2005003460A1 (en) * 2003-07-01 2005-01-13 Stora Enso Oyj A heat treated package formed from fibre based packaging material
FR2872136A1 (en) * 2004-06-24 2005-12-30 Teich Ag Lid for foodstuff containers comprises at least a three-layered carrier material which has a symmetric structure consisting of a paper core layer and polyester cover layers
WO2008023092A1 (en) * 2006-08-24 2008-02-28 Stora Enso Oyj Method for controlling surface contact area of a paper or board substrate
CN100374287C (en) * 2003-04-07 2008-03-12 利乐拉瓦尔集团及财务有限公司 Method for producing packaging laminated material
WO2008066487A1 (en) * 2006-12-01 2008-06-05 Akzo Nobel N.V. Packaging laminate
WO2008091185A1 (en) * 2007-01-24 2008-07-31 Tetra Laval Holdings & Finance S.A. A method of treating a packed food for purposes of extending its shelf-life
WO2009040347A3 (en) * 2007-09-24 2009-07-02 Sig Technology Ag Device for sterilizing cuboid cartons/plastic combination packs in an autoclave, and suitable package therefor
WO2011092002A1 (en) * 2010-01-27 2011-08-04 Sig Technology Ag Container for foodstuff made from an aluminium-free planar composite with a covered hole as part of a closure system
WO2011091987A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with an inner layer by hot folding
WO2011092037A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with a multiple inner layer by hot folding
WO2011091989A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with a multiple inner layer by cold folding
WO2011091988A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with an inner layer by cold folding
RU2444440C2 (en) * 2006-12-01 2012-03-10 Акцо Нобель Н.В. Packing laminate
RU2487065C2 (en) * 2008-03-14 2013-07-10 Тетра Лаваль Холдингз Энд Файнэнс С.А. Multilayer packaging material, method of production multilayer packaging material, and packaging container made of it
EP2682523A1 (en) * 2012-07-03 2014-01-08 Huhtamäki Oyj A recyclable sheet material and a container thereof
US9700915B2 (en) 2010-12-17 2017-07-11 Cellutech Ab Method for production of superhydrophobic surfaces
US11339539B2 (en) 2017-11-01 2022-05-24 Kemira Oyj Polymer product for improving retention of hydrophobic internal sizing agents in manufacture of paper or board
EP3943293A4 (en) * 2019-03-18 2022-12-21 Nippon Paper Industries Co., Ltd. Paper barrier material

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070292567A1 (en) * 2005-12-30 2007-12-20 Lithotype Company, Inc. E-beam cured packaging structure, packages, and methods of making
US8002170B2 (en) 2008-07-25 2011-08-23 Sonoco Development, Inc. Dual-ovenable container formed of a paper-based laminate
EP2451641B1 (en) * 2009-07-08 2016-05-04 Tetra Laval Holdings & Finance S.A. High barrier packaging laminate, method for manufacturing of the packaging laminate and packaging container
DK2451644T3 (en) * 2009-07-08 2014-06-30 Tetra Laval Holdings & Finance NON-METAL FOLIAMINATED POSITION MATERIAL, PROCEDURE FOR PREPARING THE POSITION MATERIAL AND PACKAGING PAPER MANUFACTURED THEREOF
UA110221C2 (en) * 2010-09-28 2015-12-10 Tetra Laval Holdings & Finance Method for producing packaging materials for packaging, sterilized, packaging materials and packaging
RU2475579C1 (en) * 2011-09-06 2013-02-20 Российская Федерация в лице Министерства промышленности и торговли Российской Федерации Paper pulp for production of sterilisation wrapping paper
US9463893B2 (en) * 2011-12-29 2016-10-11 Tetra Laval Holdings & Finance S. A. Packaging laminate for a packaging container, as well as a packaging container produced from the packaging laminate
CA3000532A1 (en) * 2015-10-08 2017-04-13 Basf Se Preparation of retort packaging ink through cross-linking of polyurethane resins
JP6760747B2 (en) * 2016-03-30 2020-09-23 特種東海製紙株式会社 Sterilization paper
CN105966017A (en) * 2016-06-08 2016-09-28 竹菱（大连）实业有限公司 Nanometer non-sticky film
WO2018081501A1 (en) * 2016-10-28 2018-05-03 Basf Se Preparation of retort packaging ink through incorporation of polyethylene glycol into polyurethane resins

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4522686A (en) * 1981-09-15 1985-06-11 Hercules Incorporated Aqueous sizing compositions
EP0292975A1 (en) * 1987-05-26 1988-11-30 Hercules Incorporated Sizing pulp
EP0580405A1 (en) * 1992-07-21 1994-01-26 Hercules Incorporated Use of a composition for sizing paper and cardboard
WO1996017127A1 (en) * 1994-12-02 1996-06-06 Eka Chemicals Ab Sizing dispersions
WO1998016431A1 (en) * 1996-10-16 1998-04-23 Tetra Laval Holdings & Finance S.A. A method of sterilizing containers based on fiber

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3885730A (en) * 1974-03-07 1975-05-27 Christenssons Maskiner Sterilizable package
US4296012A (en) * 1978-12-28 1981-10-20 Arakawa Kagaku Kogyo Kabushiki Kaisha Sizing compositions incorporating ketene dimer
US4279344A (en) * 1979-12-26 1981-07-21 Reynolds Metals Company Heat-sealable and peelable laminated packaging construction
ES8606559A1 (en) * 1982-10-20 1986-04-01 Wiggins Teape Group Ltd Papermaking.
SE508593C2 (en) * 1996-03-29 1998-10-19 Stora Kopparbergs Bergslags Ab Bonding composition and method of use thereof in the manufacture of paper
SE0003245L (en) * 2000-09-13 2002-03-14 Tetra Laval Holdings & Finance Packaging laminate for an autoclavable packaging container
SE522090C2 (en) * 2000-10-03 2004-01-13 Tetra Laval Holdings & Finance Packaging laminate for an autoclavable packaging container and packaging container made of the laminate

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4522686A (en) * 1981-09-15 1985-06-11 Hercules Incorporated Aqueous sizing compositions
EP0292975A1 (en) * 1987-05-26 1988-11-30 Hercules Incorporated Sizing pulp
EP0580405A1 (en) * 1992-07-21 1994-01-26 Hercules Incorporated Use of a composition for sizing paper and cardboard
WO1996017127A1 (en) * 1994-12-02 1996-06-06 Eka Chemicals Ab Sizing dispersions
WO1998016431A1 (en) * 1996-10-16 1998-04-23 Tetra Laval Holdings & Finance S.A. A method of sterilizing containers based on fiber

Cited By (41)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003097351A1 (en) * 2002-05-15 2003-11-27 Knut Magne Furuheim A method for manufacturing laminated hd (high-density) paper with good oxygen-barrier properties, and hd paper obtained thereby
AU2003241227B2 (en) * 2002-05-15 2008-12-11 Knut Magne Furuheim A method for manufacturing laminated HD (high-density) paper with good oxygen-barrier properties, and HD paper obtained thereby
CN100374287C (en) * 2003-04-07 2008-03-12 利乐拉瓦尔集团及财务有限公司 Method for producing packaging laminated material
WO2004101279A1 (en) * 2003-05-16 2004-11-25 Basf Aktiengesellschaft Packaging material consisting of an at least double-layered composite material for producing containers for packing liquids
EP1639201B2 (en) † 2003-07-01 2016-02-17 Stora Enso Oyj A heat treated package formed from fibre based packaging material
KR101110499B1 (en) * 2003-07-01 2012-01-31 스토라 엔소 오와이제이 A heat treated package formed from fibre based packaging material
WO2005003460A1 (en) * 2003-07-01 2005-01-13 Stora Enso Oyj A heat treated package formed from fibre based packaging material
AU2004254075B2 (en) * 2003-07-01 2008-12-11 Stora Enso Oyj A heat treated package formed from fibre based packaging material
US7779998B2 (en) 2003-07-01 2010-08-24 Stora Enso Oyj Heat treated package formed from fibre based packaging material
FR2872136A1 (en) * 2004-06-24 2005-12-30 Teich Ag Lid for foodstuff containers comprises at least a three-layered carrier material which has a symmetric structure consisting of a paper core layer and polyester cover layers
US8455057B2 (en) 2006-08-24 2013-06-04 Stora Enso Oyj Method for controlling surface contact area of a paper or board substrate
WO2008023092A1 (en) * 2006-08-24 2008-02-28 Stora Enso Oyj Method for controlling surface contact area of a paper or board substrate
WO2008066487A1 (en) * 2006-12-01 2008-06-05 Akzo Nobel N.V. Packaging laminate
WO2008066489A1 (en) * 2006-12-01 2008-06-05 Akzo Nobel N.V. Packaging laminate
RU2444440C2 (en) * 2006-12-01 2012-03-10 Акцо Нобель Н.В. Packing laminate
EP2109373A1 (en) * 2007-01-24 2009-10-21 Tetra Laval Holdings & Finance SA A method of treating a packed food for purposes of extending its shelf-life
EP2109373A4 (en) * 2007-01-24 2012-05-16 Tetra Laval Holdings & Finance A method of treating a packed food for purposes of extending its shelf-life
WO2008091185A1 (en) * 2007-01-24 2008-07-31 Tetra Laval Holdings & Finance S.A. A method of treating a packed food for purposes of extending its shelf-life
EP2561769B1 (en) 2007-09-24 2017-11-01 SIG Technology AG Emballage composite carton/plastique carré destiné à être utilisé dans un dispositif de stérilisation d'emballages composites carton/plastique carrés dans un autoclave
EP2561769A1 (en) * 2007-09-24 2013-02-27 SIG Technology AG Emballage composite carton/plastique carré destiné à être utilisé dans un dispositif de stérilisation d'emballages composites carton/plastique carrés dans un autoclave
US9505513B2 (en) 2007-09-24 2016-11-29 Sig Technology Ag Device for sterilising cuboid-shaped cardboard/plastic combipacks in an autoclave and pack suitable for this
US9359096B2 (en) 2007-09-24 2016-06-07 Sig Technology Ag Method for sterilizing cuboid-shaped cardboard/plastic combipacks in an autoclave and pack suitable for this
WO2009040347A3 (en) * 2007-09-24 2009-07-02 Sig Technology Ag Device for sterilizing cuboid cartons/plastic combination packs in an autoclave, and suitable package therefor
TWI422401B (en) * 2007-09-24 2014-01-11 Sig Technology Ag Device for the sterilizing of parallelepiped cardboard/plastic composite packings in an autoclave
RU2494655C2 (en) * 2007-09-24 2013-10-10 Сиг Текнолоджи Аг Device for sterilisation of rectangular cardboard/plastic layered packages in autoclave and package suitable for purpose
RU2487065C2 (en) * 2008-03-14 2013-07-10 Тетра Лаваль Холдингз Энд Файнэнс С.А. Multilayer packaging material, method of production multilayer packaging material, and packaging container made of it
WO2011091987A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with an inner layer by hot folding
WO2011091989A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with a multiple inner layer by cold folding
EP2528732B1 (en) 2010-01-26 2019-12-11 SIG Technology AG Process for the production of a container from a planar composite with a multiple inner layer by hot folding
CN102725136A (en) * 2010-01-26 2012-10-10 Sig科技公司 Process for the production of a container for foodstuff from an aluminium-free planar composite with an inner layer by hot folding
CN102725137A (en) * 2010-01-26 2012-10-10 Sig科技公司 Process for the production of a container for foodstuff from an aluminium-free planar composite with an inner layer by cold folding
WO2011091988A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with an inner layer by cold folding
WO2011092037A1 (en) * 2010-01-26 2011-08-04 Sig Technology Ag Process for the production of a container for foodstuff from an aluminium-free planar composite with a multiple inner layer by hot folding
WO2011092002A1 (en) * 2010-01-27 2011-08-04 Sig Technology Ag Container for foodstuff made from an aluminium-free planar composite with a covered hole as part of a closure system
EA025444B1 (en) * 2010-01-27 2016-12-30 Сиг Текнолоджи Аг Container for foodstuff
US9511559B2 (en) 2010-01-27 2016-12-06 Sig Technology Ag Container for foodstuff made from an aluminium-free planar composite with a covered hole as part of a closure system
US9700915B2 (en) 2010-12-17 2017-07-11 Cellutech Ab Method for production of superhydrophobic surfaces
EP2682523A1 (en) * 2012-07-03 2014-01-08 Huhtamäki Oyj A recyclable sheet material and a container thereof
US11339539B2 (en) 2017-11-01 2022-05-24 Kemira Oyj Polymer product for improving retention of hydrophobic internal sizing agents in manufacture of paper or board
EP3943293A4 (en) * 2019-03-18 2022-12-21 Nippon Paper Industries Co., Ltd. Paper barrier material
US11905662B2 (en) 2019-03-18 2024-02-20 Nippon Paper Industries Co., Ltd. Paper barrier material

Also Published As

Publication number Publication date
EP1401726A1 (en) 2004-03-31
CN1507405A (en) 2004-06-23
AU2002306037B2 (en) 2007-06-14
SE0101673L (en) 2002-11-11
RU2003135793A (en) 2005-02-27
MXPA03010147A (en) 2004-03-16
CA2446548A1 (en) 2002-11-14
RU2289535C2 (en) 2006-12-20
JP2005508800A (en) 2005-04-07
SE0101673D0 (en) 2001-05-10
US20040170781A1 (en) 2004-09-02
AU2002306037B8 (en) 2002-11-18
CN1275766C (en) 2006-09-20

Similar Documents

Publication Publication Date Title
AU2002306037B2 (en) A packaging laminate for a retortable packaging container
AU2002306037A1 (en) A packaging laminate for a retortable packaging container
AU702390B2 (en) Packaging laminates based on cardboard and paper
US7384674B2 (en) Packaging laminate for a retortable packaging container
US7276281B2 (en) Containers prepared from laminate structures having a foamed polymer layer
US7195803B2 (en) Packaging laminate for a retortable packaging container
AU2002341525A1 (en) A packaging laminate for a retortable packaging container
WO1997002181A1 (en) A food packaging and a method for treating the same
AU2001292497A1 (en) A packaging laminate for a retortable packaging container
WO2000021854A1 (en) Oven release food packaging
EP0840678B1 (en) Method for manufacturing a packaging container from a laminate
US20030207054A1 (en) Packaging laminates based on cardboard and paper
JP2007126177A (en) Retort sterilizing method of paper container
MXPA01001343A (en) Containers prepared from laminate structures having a foamed polymer layer

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG US UZ VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
WWE Wipo information: entry into national phase

Ref document number: 2002733656

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: PA/a/2003/010147

Country of ref document: MX

Ref document number: 2446548

Country of ref document: CA

WWE Wipo information: entry into national phase

Ref document number: 2002587298

Country of ref document: JP

Ref document number: 028095766

Country of ref document: CN

Ref document number: 2002306037

Country of ref document: AU

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

WWP Wipo information: published in national office

Ref document number: 2002733656

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 10477123

Country of ref document: US

WWG Wipo information: grant in national office

Ref document number: 2002306037

Country of ref document: AU