EP4308375A1 - Packaging laminate for containers - Google Patents

Packaging laminate for containers

Info

Publication number
EP4308375A1
EP4308375A1 EP22717739.1A EP22717739A EP4308375A1 EP 4308375 A1 EP4308375 A1 EP 4308375A1 EP 22717739 A EP22717739 A EP 22717739A EP 4308375 A1 EP4308375 A1 EP 4308375A1
Authority
EP
European Patent Office
Prior art keywords
layer
packaging laminate
constituent
barrier
thermoplastic polymer
Prior art date
Legal status (The legal status 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 status listed.)
Pending
Application number
EP22717739.1A
Other languages
German (de)
French (fr)
Inventor
Albert Menalda
Aaladin Ben-abdelmoumen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ALTERNAPAK HOLDING BV
Original Assignee
ALTERNAPAK HOLDING BV
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 ALTERNAPAK HOLDING BV filed Critical ALTERNAPAK HOLDING BV
Publication of EP4308375A1 publication Critical patent/EP4308375A1/en
Pending legal-status Critical Current

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
    • 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
    • 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
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B32B15/082—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin comprising vinyl resins; comprising acrylic resins
    • 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
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B32B15/085—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin comprising polyolefins
    • 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
    • B32B27/08—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 synthetic resin
    • 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
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
    • 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
    • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
    • B32B27/304—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
    • 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
    • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
    • B32B27/306—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl acetate or vinyl alcohol (co)polymers
    • 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
    • B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
    • 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
    • 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
    • B32B2250/00—Layers arrangement
    • B32B2250/05—5 or more layers
    • 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
    • B32B2270/00—Resin or rubber layer containing a blend of at least two different polymers
    • 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
    • B32B2307/50—Properties of the layers or laminate having particular mechanical properties
    • B32B2307/54—Yield strength; Tensile strength
    • 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
    • B32B2307/718—Weight, e.g. weight per square meter
    • 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
    • B32B2307/72—Density
    • 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

Definitions

  • the present invention relates to a packaging laminate for containers for liquids, such as milk or juice, and/or solids, such as granulated sugar, said laminate comprising, a thermoplastic polymer outermost layer, a substrate layer, typically made from paper or cardboard, a barrier layer, a thermoplastic polymer innermost (sealing) layer, and a tie layer between the substrate layer and the barrier layer, which tie layer comprises two constituent layers, a first constituent layer facing the substrate and a second constituent layer facing the barrier, which second constituent layer comprises, preferably for the greater part or wholly, an adhesive thermoplastic polymer.
  • WO 98/26994 relates to liquid-tight packaging laminates with improved mechanical strength and flexibility, with an outer layer of a mixture of metallocene-polyethylene and low density polyethylene (LDPE), and mechanically strong liquid-tight packaging containers produced from the packaging laminate.
  • the packaging laminate also has improved friction properties and improved resistance to stress-cracking as a result of fat- or fatty acid-containing substances.
  • the laminate includes a core layer of paper and at least one outer layer including a mixture of metallocene-polyethylene and LDPE.
  • the packaging laminate may also include an additional gas barrier layer and adhesion layer.
  • EP 1507 660 relates to a packaging laminate (10) comprising a core layer of paper or carton (11) with a through-going hole, a layer of thermoplastics (12) applied onto one outer side of the core layer, an aluminium foil (13) applied onto the other, inner, side of the core layer and bonded to the core layer by means of an intermediate layer (14) of thermoplastics, the two layers of thermoplastics (12, 14) being sealed to each other within the region of the hole to form a membrane of aluminium foil and thermoplastics, and a first adhesive part-layer (15-1) applied onto the inner side of the aluminium foil, a second intermediate part-layer (15-2) of low density polyethylene (LDPE) applied adjacent to the first adhesive part-layer, and a third innermost part-layer (15-3) comprising in the majority a metallocene-polyethylene (m-PE).
  • m-PE metallocene-polyethylene
  • WO 2013/013802 relates to a sheetlike composite (3) comprising a layer configuration with the following layers: 0. optionally a layer of thermoplastic KSu (13); 1. a carrier layer (4); ii. a first layer of thermoplastic KSv (35); iii. a barrier layer (5); iv. a second layer of thermoplastic KSa (6); v. at least one further layer of thermoplastic KSw (7); wherein the Vicat softening temperature of the layer of thermoplastic KSv (35) and the Vicat softening temperature of the layer of thermoplastic KSa (6) is in each case higher than the Vicat softening temperature of the layer of thermoplastic KSw (7).
  • the first constituent layer comprises an adhesive thermoplastic polymer and a supporting thermoplastic polymer having a tensile modulus (as defined in ISO 527) of 400 MPa or higher.
  • the supporting polymer has a tensile modulus of 500 MPa or higher, preferably 600 MPa or higher, e.g. in a range from 600 to 1500 MPa.
  • the supporting polymer comprises a polyolefin, preferably a high density polyethylene (HDPE).
  • Barrier layers are typically as thin as possible and therefore fragile. Forming a container from the laminate, which involves bending and/or folding, and use of the container, including transport and storage, may cause defects, in particular cracks, in the barrier layer, for instance at the bottom corners of the container. It was found that a supporting layer made from a high stiffness polymer and adhered firmly to the substrate and to the adhesive layer between the supporting layer and the barrier significantly reduces formation of cracks in the barrier and/or helps avoiding such cracks altogether, in particular where the barrier is located (relative to the substrate layer) on the inside of bends and folds.
  • strain beyond failure is the root cause of the formation of cracks in the barrier layer and that, by firmly adhering the barrier layer to a high stiffness supporting layer, essentially over its entire surface, strain - and thus the formation of cracks - in the barrier layer is counteracted .
  • the laminate according to the present invention must have the layers specified in the independent claim, further layers may be present.
  • a layer of ink is typically present on the outermost layer or, preferably, between the polymer outermost layer and the substrate layer.
  • two or more adjacent layers that are identical are considered to be one layer. This is relevant in that in film coextrusion in a flexible production environment, where different configurations of laminates are made, it often occurs that two channels of the same feedblock are fed from a single extruder (to avoid having to exchange the entire feedblock for a new batch of laminate), consequently forming two identical and adjacent layers.
  • the tensile module is a property of the polymer before extrusion and defined in ISO 527-1:2019, Plastics — Determination of tensile properties — Part 1: General principles, paragraph 3.9, and measured in accordance with ISO 527-2:2018.
  • the first and second constituent layers both comprise a blend of two or more polymers and the blends have at least one polymer, preferably at least two polymers, e.g. a polyolefin and an adhesive polymer, in common.
  • the supporting polymer has a density of 0.93 kg/dm3 or more, preferably a density of 0.95 kg/dm3 or more, e.g. a density in a range from 0.95 to 0.98 kg/dm3.
  • the first constituent layer has a weight per unit area of at least 12 g/m2, preferably at least 15 g/m2, e.g. a weight per unit area in a range from 15 to 30 g/m2.
  • the adhesive thermoplastic polymer in the first constituent layer is 20 wt% or less, preferably 12 wt% or less, of the total weight of the first constituent layer.
  • the second constituent layer facing the barrier has a weight per unit area of 5 g/m2 or less. It preferably contains at least 50 wt% of the total weight of the second constituent layer, preferably at least 80 wt%, preferably in a range from 95 to 100 wt%, adhesive polymer.
  • the packaging laminate comprises, between the barrier layer and the innermost layer, a further layer comprising a supporting thermoplastic polymer having a tensile modulus of 400 MPa or higher, preferably a tensile modulus of 500 MPa or higher, preferably 600 MPa or higher, preferably in a range from 600 to 1500 MPa.
  • the further layer reduces formation of cracks in the barrier and/or helps avoiding such cracks altogether, in particular where the barrier is located (relative to the substrate layer) on the outside of bends and folds.
  • the supporting thermoplastic polymer in the further supporting layer has a density and/or weight per unit area as specified with regard to the supporting thermoplastic polymer in the first constituent layer, discussed above.
  • the further supporting layer is a blend of different polyolefins, preferably of at least a high density polyethylene (HDPE) and a low density polyethylene (LDPE).
  • HDPE high density polyethylene
  • LDPE low density polyethylene
  • the barrier layer preferably is at least one of aluminium foil, a metal/inorganic oxide thin film, an ethylene vinyl alcohol copolymer layer (EVOH layer), a nylon layer, and a polyvinylidene chloride film.
  • the substrate layer preferably is made from paper or board.
  • Kraft pulp provides paper having a good strength and low absorptivity. Examples are bleached paper (FBL), non-bleached paper (UBL), duplex paper (DUPLEX) of FBL and UBL, clay coating paper, multi-layer duplex-paper (MB), etc.
  • the thermoplastic material outermost layer may comprise a polyolefin resin, such as polyethylene, including medium density polyethylene and/or low density polyethylene, a metallocene-polyethylene (m-PE), polypropylene, and ethylene copolymers, and may have a coextruded layer containing an LLDPE that is excellent in its resistance to e.g. oil, acid and infiltration of substances .
  • the ink on the outermost layer or the outwardly facing surface of the substrate may be a water or oil based ink for flexographic printing, gravure, and/or offset printing.
  • Suitable adhesive thermoplastic polymers include ethylene vinyl acetate copolymer (EVA) and copolymers of ethylene and acrylic acid or methacrylic acid, i.e. ethylene acrylic acid copolymer (EAA), ethylene methacrylic acid copolymer (EMAA).
  • EAA ethylene acrylic acid copolymer
  • EAA ethylene methacrylic acid copolymer
  • EAA ethylene methacrylic acid copolymer
  • the invention further relates to a roll or one or more blanks, also known as sleeves, for the production of containers for a liquid, and to a container holding a liquid, such as milk or juice, and/or a solid, such as granulated sugar, comprising the packaging laminate described above.
  • Figure 1 is a cross-section of a packaging laminate according to the present invention.
  • Figure 2 schematically show a process of manufacturing the laminate shown in Figure 1.
  • Figure 1 is a cross-section of a packaging laminate comprising:
  • FIG. 1 schematically shows a process of manufacturing the laminate shown in Figure 1.
  • Virgin board 3 is fed to a laminator 11 from a roll 12.
  • a first die 13 coextrudes the adhesive and supporting layer 4 and the adhesive layer 5.
  • the barrier layer 6, aluminium foil, is applied at the same station.
  • a second die 14 coextrudes the inner layers, viz. the adhesive layer 7, the further supporting layer 8, and innermost or sealing layer 9, onto the barrier layer 6.
  • the laminate is reversed, a third die 15 extrudes the outermost layer 2 onto the board 3, and the finished laminated is wound on a roll 16.

Abstract

The invention relates to a packaging laminate (1) for containers for liquids, said laminate comprising, a thermoplastic polymer outermost layer (2), a substrate layer (3), a barrier layer (6), a thermoplastic polymer innermost layer (9), and a tie layer (4, 5) between the substrate layer (3) and the barrier layer (6), which tie layer (4, 5) comprises two constituent layers, a first constituent layer (4) facing the substrate and a second constituent layer (5) facing the barrier (6), which second constituent layer (5) comprises an adhesive thermoplastic polymer. The first constituent layer (4) comprises a blend of an adhesive thermoplastic polymer and a supporting thermoplastic polymer having a tensile modulus of 400 MPa or higher.

Description

Packaging laminate for containers
The present invention relates to a packaging laminate for containers for liquids, such as milk or juice, and/or solids, such as granulated sugar, said laminate comprising, a thermoplastic polymer outermost layer, a substrate layer, typically made from paper or cardboard, a barrier layer, a thermoplastic polymer innermost (sealing) layer, and a tie layer between the substrate layer and the barrier layer, which tie layer comprises two constituent layers, a first constituent layer facing the substrate and a second constituent layer facing the barrier, which second constituent layer comprises, preferably for the greater part or wholly, an adhesive thermoplastic polymer.
WO 98/26994 relates to liquid-tight packaging laminates with improved mechanical strength and flexibility, with an outer layer of a mixture of metallocene-polyethylene and low density polyethylene (LDPE), and mechanically strong liquid-tight packaging containers produced from the packaging laminate. The packaging laminate also has improved friction properties and improved resistance to stress-cracking as a result of fat- or fatty acid-containing substances. The laminate includes a core layer of paper and at least one outer layer including a mixture of metallocene-polyethylene and LDPE. The packaging laminate may also include an additional gas barrier layer and adhesion layer.
EP 1507 660 relates to a packaging laminate (10) comprising a core layer of paper or carton (11) with a through-going hole, a layer of thermoplastics (12) applied onto one outer side of the core layer, an aluminium foil (13) applied onto the other, inner, side of the core layer and bonded to the core layer by means of an intermediate layer (14) of thermoplastics, the two layers of thermoplastics (12, 14) being sealed to each other within the region of the hole to form a membrane of aluminium foil and thermoplastics, and a first adhesive part-layer (15-1) applied onto the inner side of the aluminium foil, a second intermediate part-layer (15-2) of low density polyethylene (LDPE) applied adjacent to the first adhesive part-layer, and a third innermost part-layer (15-3) comprising in the majority a metallocene-polyethylene (m-PE).
WO 2013/013802 relates to a sheetlike composite (3) comprising a layer configuration with the following layers: 0. optionally a layer of thermoplastic KSu (13); 1. a carrier layer (4); ii. a first layer of thermoplastic KSv (35); iii. a barrier layer (5); iv. a second layer of thermoplastic KSa (6); v. at least one further layer of thermoplastic KSw (7); wherein the Vicat softening temperature of the layer of thermoplastic KSv (35) and the Vicat softening temperature of the layer of thermoplastic KSa (6) is in each case higher than the Vicat softening temperature of the layer of thermoplastic KSw (7).
It is an object of the present invention to provide a laminate for making containers that has improved properties.
To this end, the first constituent layer comprises an adhesive thermoplastic polymer and a supporting thermoplastic polymer having a tensile modulus (as defined in ISO 527) of 400 MPa or higher. In an embodiment, the supporting polymer has a tensile modulus of 500 MPa or higher, preferably 600 MPa or higher, e.g. in a range from 600 to 1500 MPa. In another embodiment, the supporting polymer comprises a polyolefin, preferably a high density polyethylene (HDPE).
Barrier layers are typically as thin as possible and therefore fragile. Forming a container from the laminate, which involves bending and/or folding, and use of the container, including transport and storage, may cause defects, in particular cracks, in the barrier layer, for instance at the bottom corners of the container. It was found that a supporting layer made from a high stiffness polymer and adhered firmly to the substrate and to the adhesive layer between the supporting layer and the barrier significantly reduces formation of cracks in the barrier and/or helps avoiding such cracks altogether, in particular where the barrier is located (relative to the substrate layer) on the inside of bends and folds. It is believed that strain beyond failure is the root cause of the formation of cracks in the barrier layer and that, by firmly adhering the barrier layer to a high stiffness supporting layer, essentially over its entire surface, strain - and thus the formation of cracks - in the barrier layer is counteracted .
Although the laminate according to the present invention must have the layers specified in the independent claim, further layers may be present. For instance, a layer of ink is typically present on the outermost layer or, preferably, between the polymer outermost layer and the substrate layer.
Further, within the framework of the present invention, two or more adjacent layers that are identical are considered to be one layer. This is relevant in that in film coextrusion in a flexible production environment, where different configurations of laminates are made, it often occurs that two channels of the same feedblock are fed from a single extruder (to avoid having to exchange the entire feedblock for a new batch of laminate), consequently forming two identical and adjacent layers.
The tensile module is a property of the polymer before extrusion and defined in ISO 527-1:2019, Plastics — Determination of tensile properties — Part 1: General principles, paragraph 3.9, and measured in accordance with ISO 527-2:2018.
In an embodiment, to further improve adhesion between the constituent layers, the first and second constituent layers both comprise a blend of two or more polymers and the blends have at least one polymer, preferably at least two polymers, e.g. a polyolefin and an adhesive polymer, in common.
In an embodiment, the supporting polymer has a density of 0.93 kg/dm3 or more, preferably a density of 0.95 kg/dm3 or more, e.g. a density in a range from 0.95 to 0.98 kg/dm3.
In an embodiment, the first constituent layer has a weight per unit area of at least 12 g/m2, preferably at least 15 g/m2, e.g. a weight per unit area in a range from 15 to 30 g/m2.
In an embodiment, the adhesive thermoplastic polymer in the first constituent layer is 20 wt% or less, preferably 12 wt% or less, of the total weight of the first constituent layer.
In an embodiment, the second constituent layer facing the barrier has a weight per unit area of 5 g/m2 or less. It preferably contains at least 50 wt% of the total weight of the second constituent layer, preferably at least 80 wt%, preferably in a range from 95 to 100 wt%, adhesive polymer.
These configurations combine, on the one hand, good adhesion between the substrate and the tie layer, between the constituents of the tie layer, and between the tie layer and the barrier layer, and, on the other hand, enable an efficient use of adhesive thermoplastic polymer, which typically is an expensive component (per unit of weight) in the laminate.
In an embodiment, the packaging laminate comprises, between the barrier layer and the innermost layer, a further layer comprising a supporting thermoplastic polymer having a tensile modulus of 400 MPa or higher, preferably a tensile modulus of 500 MPa or higher, preferably 600 MPa or higher, preferably in a range from 600 to 1500 MPa.
The further layer reduces formation of cracks in the barrier and/or helps avoiding such cracks altogether, in particular where the barrier is located (relative to the substrate layer) on the outside of bends and folds.
In an embodiment, the supporting thermoplastic polymer in the further supporting layer has a density and/or weight per unit area as specified with regard to the supporting thermoplastic polymer in the first constituent layer, discussed above.
In an embodiment, the further supporting layer is a blend of different polyolefins, preferably of at least a high density polyethylene (HDPE) and a low density polyethylene (LDPE).
The barrier layer preferably is at least one of aluminium foil, a metal/inorganic oxide thin film, an ethylene vinyl alcohol copolymer layer (EVOH layer), a nylon layer, and a polyvinylidene chloride film.
The substrate layer preferably is made from paper or board. Kraft pulp provides paper having a good strength and low absorptivity. Examples are bleached paper (FBL), non-bleached paper (UBL), duplex paper (DUPLEX) of FBL and UBL, clay coating paper, multi-layer duplex-paper (MB), etc. The thermoplastic material outermost layer may comprise a polyolefin resin, such as polyethylene, including medium density polyethylene and/or low density polyethylene, a metallocene-polyethylene (m-PE), polypropylene, and ethylene copolymers, and may have a coextruded layer containing an LLDPE that is excellent in its resistance to e.g. oil, acid and infiltration of substances .
The ink on the outermost layer or the outwardly facing surface of the substrate may be a water or oil based ink for flexographic printing, gravure, and/or offset printing.
Examples of suitable adhesive thermoplastic polymers include ethylene vinyl acetate copolymer (EVA) and copolymers of ethylene and acrylic acid or methacrylic acid, i.e. ethylene acrylic acid copolymer (EAA), ethylene methacrylic acid copolymer (EMAA).
The invention further relates to a roll or one or more blanks, also known as sleeves, for the production of containers for a liquid, and to a container holding a liquid, such as milk or juice, and/or a solid, such as granulated sugar, comprising the packaging laminate described above.
The invention will now be explained in more detail with reference to the figures, which schematically show an embodiment according to the present invention.
Figure 1 is a cross-section of a packaging laminate according to the present invention.
Figure 2 schematically show a process of manufacturing the laminate shown in Figure 1. Figure 1 is a cross-section of a packaging laminate comprising:
Table 1 Packaging laminate (1) g/m2
Outermost layer LDPE Ineos 19N430 15
(2)
Substrate (3) Board 245
Tie, adhesive and 50 wt% HDPE Ineos Rigidex® HD6070FA 18 supporting layer 40 wt% LDPE Dow™ PT 7007
(4) 10 wt% EMAA Ineos M21N430
Tie, adhesive 30 wt% LDPE Dow™ PT 7007 3 layer (5) 70 wt% EMAA Ineos M21N430
Barrier (6) Aluminum foil 17
Tie, adhesive Escor 6000 Exxon 5 layer (7)
Further supporting 50 wt% HDPE Ineos Rigidex® HD6070FA 7 layer (8) 50 wt% LDPE Dow™ PT 7007
Innermost layer 70 wt% LDPE Dow™ PT 7007 20
(9) 30 wt% m-LLDPE Eltex® PF1315AZ Figure 2 schematically shows a process of manufacturing the laminate shown in Figure 1. Virgin board 3 is fed to a laminator 11 from a roll 12. A first die 13 coextrudes the adhesive and supporting layer 4 and the adhesive layer 5. The barrier layer 6, aluminium foil, is applied at the same station. Next, a second die 14 coextrudes the inner layers, viz. the adhesive layer 7, the further supporting layer 8, and innermost or sealing layer 9, onto the barrier layer 6. Finally, the laminate is reversed, a third die 15 extrudes the outermost layer 2 onto the board 3, and the finished laminated is wound on a roll 16.
The invention is not restricted to the above- described embodiments, which can be varied in a number of ways within the scope of the claims.

Claims

1. A packaging laminate (1) for containers, said laminate comprising, a thermoplastic polymer outermost layer (2), a substrate layer (3), a barrier layer (6), a thermoplastic polymer innermost layer (9), and a tie layer (4, 5) between the substrate layer (3) and the barrier layer (6), which tie layer (4, 5) comprises two constituent layers, a first constituent layer (4) facing the substrate and a second constituent layer (5) facing the barrier (6), which second constituent layer (5) comprises an adhesive thermoplastic polymer, characterised in that the first constituent layer (4) comprises an adhesive thermoplastic polymer and a supporting thermoplastic polymer having a tensile modulus of 400 MPa or higher.
2. The packaging laminate of claim 1, wherein the supporting polymer has a tensile modulus of 500 MPa or higher, preferably 600 MPa or higher.
3. The packaging laminate of claim 1 or 2, wherein the supporting polymer comprises a polyolefin, preferably a high density polyethylene (HDPE).
4. The packaging laminate of any one of the preceding claims, wherein the first constituent layer (4) facing the substrate and the second constituent layer (5) facing the barrier (6) both comprise a blend of two or more polymers and wherein the blends have at least one polymer in common.
5. The packaging laminate of any one of the preceding claims, wherein the supporting polymer has a density of 0.90 kg/dm3 or more, preferably a density of
0.95 kg/dm3 or more, e.g. has a density in a range from 0.95 to 0.98 kg/dm3.
6. The packaging laminate of any one of the preceding claims, wherein the first constituent layer (4) has a weight per unit area of at least 12 g/m2, preferably at least 15 g/m2.
7. The packaging laminate of any one of the preceding claims, wherein the adhesive thermoplastic polymer in the first constituent layer (4) is 20 wt% or less, preferably 12 wt% or less, of the total weight of the first constituent layer.
8. The packaging laminate of any one of the pre-ceding claims, wherein second constituent layer (5) facing the barrier (6) has a weight per unit area of 5 g/m2 or less.
9. The packaging laminate of any one of the preceding claims, comprising, between the barrier layer (6) and the innermost layer (9), a further layer (8) comprising a supporting thermoplastic polymer having a tensile modulus of 400 MPa or higher, preferably a tensile modulus of 500 MPa or higher, preferably 600 Mpa or higher.
10. The packaging laminate according to claim 9, wherein the further supporting layer (8) is a polymer and/or has a density and/or weight per unit area as specified in claims 3, 5, and 6.
11. The packaging laminate according to claim 9 or 10, the further supporting layer (8) is a blend of polyolefins, preferably of at least a high density polyethylene (HDPE) and a low density polyethylene
(LDPE).
12. The packaging laminate of any one of the preceding claims, wherein the barrier layer (6) is at least one of aluminium foil, a metal/inorganic oxide thin film, an ethylene vinyl alcohol copolymer layer (EVOH layer), a nylon layer, a polyvinylidene chloride film.
13. The packaging laminate of any one of the preceding claims, wherein substrate layer is made from paper or board.
14. Roll (16) or one or more blanks, also known as sleeves, for the production of containers for a liquid, such as milk or juice, which rolls or blanks are made from the packaging laminate of any one of the preceding claims.
15. Container holding a liquid, such as milk or juice, and/or a solid, such as granulated sugar, made from the packaging laminate of any one of the preceding claims.
EP22717739.1A 2021-03-19 2022-03-21 Packaging laminate for containers Pending EP4308375A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP21163786.3A EP4059706A1 (en) 2021-03-19 2021-03-19 Packaging laminate for containers
PCT/EP2022/057349 WO2022195128A1 (en) 2021-03-19 2022-03-21 Packaging laminate for containers

Publications (1)

Publication Number Publication Date
EP4308375A1 true EP4308375A1 (en) 2024-01-24

Family

ID=75111536

Family Applications (2)

Application Number Title Priority Date Filing Date
EP21163786.3A Withdrawn EP4059706A1 (en) 2021-03-19 2021-03-19 Packaging laminate for containers
EP22717739.1A Pending EP4308375A1 (en) 2021-03-19 2022-03-21 Packaging laminate for containers

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP21163786.3A Withdrawn EP4059706A1 (en) 2021-03-19 2021-03-19 Packaging laminate for containers

Country Status (2)

Country Link
EP (2) EP4059706A1 (en)
WO (1) WO2022195128A1 (en)

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE9604687L (en) 1996-12-19 1998-06-20 Tetra Laval Holdings & Finance Packaging laminate, methods of making the packaging laminate and packaging containers
SE523861C2 (en) 2002-05-07 2004-05-25 Tetra Laval Holdings & Finance Packaging laminate, method of manufacture thereof, and packaging container made of packaging laminate
DE102011108401A1 (en) 2011-07-26 2013-01-31 Sig Technology Ag Robust laminar composite with an intermediate layer with increased Vicat softening temperature
EP2767397A1 (en) * 2013-02-18 2014-08-20 Tetra Laval Holdings & Finance S.A. Packaging laminate, method for producing same, and packaging container produced from the packaging container
SE538498C2 (en) * 2014-02-19 2016-08-09 Stora Enso Oyj Process for making a packaging material
JP6685994B2 (en) * 2014-07-14 2020-04-22 テトラ ラバル ホールディングス アンド ファイナンス エス エイ Method for manufacturing laminated packaging material and laminated packaging material

Also Published As

Publication number Publication date
EP4059706A1 (en) 2022-09-21
WO2022195128A1 (en) 2022-09-22

Similar Documents

Publication Publication Date Title
KR100674777B1 (en) Laminated packaging material and method for producing the same
EP2475520B1 (en) A barrier coated thermo-mechanically stable, heat sealable film, a packaging laminate comprising the film, a packaging container formed from the packaging laminate and a method for the production of the film
RU2730526C2 (en) Multilayer packaging material, packaging containers made therefrom and method of producing multilayer material
EP2956303B2 (en) Packaging laminate, method for producing same, and packaging container produced from the packaging laminate
US7252878B2 (en) High barrier flexible packaging structure
EP2451642B1 (en) Laminated packaging material for a container
US20200122439A1 (en) Recyclable, Easily Tearable Packaging Laminate Having A Good Barrier Effect And Method For Production Thereof
CA2464195A1 (en) A packaging laminate for a retortable packaging container
EP1920919B1 (en) Packaging layered material
WO2006031172A1 (en) A strip tape, a packaging container having such a strip tape, and a method of producing such a strip tape
CA2923213A1 (en) Packaging and material for making same
US20190077132A1 (en) Laminated packaging material comprising a barrier film and packaging containers manufactured therefrom
KR20130042517A (en) Multilayered laminate for tubes having an embedded aluminium layer, a process for the production thereof and a tube produced therefrom
CN109070562B (en) Polyester laminated tube for container
CN116745125A (en) Recyclable cardboard packaging material comprising a metallized barrier layer applied by transfer metallization
EP4059706A1 (en) Packaging laminate for containers
JP4155426B2 (en) Packaging materials for paper containers
JPH11334756A (en) Semi-material for paper container, production of semi-material for paper container, paper container packaging material and paper container
CN116745107A (en) Recyclable paper base combination and beverage carton made therefrom
SE527944C2 (en) Packaging laminate in plastic and with gas barrier, packaging container and method for producing the packaging laminate
CN112585010B (en) Easily recyclable, easily tearable packaging laminate with good barrier effect and method for its manufacture
EP0665785B1 (en) Laminating method
EP3368300B1 (en) Laminated packaging material comprising a barrier film and packaging containers manufactured therefrom
JP4129899B2 (en) Manufacturing method of packaging materials for paper containers
EP4253047A1 (en) A laminated packaging material and packaging container manufactured therefrom

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20230929

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR