Gas-Barrier Laminate

• US 20070224402A1
• Filed: 03/23/2005
• Published: 09/27/2007
• Est. Priority Date: 03/25/2004
• Status: Active Grant

• Current Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.)
• Original Assignee: Mitsubishi Plastics Incorporated (Mitsubishi Chemical Group Corp.)
• Inventors: Hachisuka, Tooru, Yoshida, Shigenobu, Okawara, Chiharu
• Granted Patent: US 7,910,213 B2
• Time in Patent Office: Days
• US Class Current: 428/220
• CPC Class Codes: B32B 2250/02 2 layers
• CPC Class Codes: B32B 2250/03 3 layers
• CPC Class Codes: B32B 2250/24 All layers being polymeric
• CPC Class Codes: B32B 2255/10 on synthetic resin layer or on natural or synthetic rubber layer
• CPC Class Codes: B32B 2255/20 Inorganic coating
• CPC Class Codes: B32B 2255/26 Polymeric coating
• CPC Class Codes: B32B 2255/28 Multiple coating on one surface
• CPC Class Codes: B32B 2270/00 Resin or rubber layer containing a blend of at least two different polymers
• CPC Class Codes: B32B 2307/31 Heat sealable
• CPC Class Codes: B32B 2307/4023 on the layer surface, e.g. ink
• CPC Class Codes: B32B 2307/412 Transparent
• CPC Class Codes: B32B 2307/546 Flexural strength; Flexion stiffness
• CPC Class Codes: B32B 2307/7163 Biodegradable
• CPC Class Codes: B32B 2307/7242 Non-permeable
• CPC Class Codes: B32B 2307/7244 Oxygen barrier
• CPC Class Codes: B32B 2307/732 Dimensional properties
• CPC Class Codes: B32B 2307/748 Releasability
• CPC Class Codes: B32B 2307/75 Printability
• CPC Class Codes: B32B 2439/00 Containers; Receptacles
• CPC Class Codes: B32B 2439/40 Closed containers
• CPC Class Codes: B32B 27/08 : of synthetic resin
• CPC Class Codes: B32B 27/10 : of paper or cardboard
• CPC Class Codes: B32B 27/281 : comprising polyimides
• CPC Class Codes: B32B 27/285 : comprising polyethers
• CPC Class Codes: B32B 27/286 : comprising polysulphones; polysulfides
• CPC Class Codes: B32B 27/288 : comprising polyketones
• CPC Class Codes: B32B 27/306 : comprising vinyl acetate or vinyl alcohol (co)polymers
• CPC Class Codes: B32B 27/308 : comprising acrylic (co)polymers
• CPC Class Codes: B32B 27/32 : comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/325 : comprising polycycloolefins
• CPC Class Codes: B32B 27/34 : comprising polyamides
• CPC Class Codes: B32B 27/36 : comprising polyesters
• CPC Class Codes: B32B 27/365 : comprising polycarbonates
• CPC Class Codes: B32B 27/42 : comprising condensation resins of aldehydes, e.g. with phenols, ureas or melamines
• CPC Class Codes: B32B 29/002 : as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/06; next to a bituminous or tarry layer B32B11/06; next to a water-setting substance layer B32B13/08; next to a metal layer B32B15/12; next to a glass layer B32B17/065; next to a layer formed of natural mineral fibres or particles B32B19/046; next to a wood layer B32B21/06; next to a cellulosic plastic layer B32B23/06; next to a natural or synthetic rubber layer B32B25/06; next to a synthetic resin layer B32B27/10
• CPC Class Codes: B32B 7/12 : using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: C08J 2323/10 : Homopolymers or copolymers of propene
• CPC Class Codes: C08J 2475/04 : Polyurethanes
• CPC Class Codes: C08J 7/0423 : with at least one layer of inorganic material and at least one layer of a composition containing a polymer binder
• CPC Class Codes: C08J 7/043 : Improving the adhesiveness of the coatings per se, e.g. forming primers adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50
• CPC Class Codes: C08J 7/046 : Forming abrasion-resistant coatings; Forming surface-hardening coatings
• CPC Class Codes: C08J 7/048 : Forming gas barrier coatings
• CPC Class Codes: Y10T 428/24851 : Intermediate layer is discontinuous or differential
• CPC Class Codes: Y10T 428/263 : Coating layer not in excess of 5 mils thick or equivalent
• CPC Class Codes: Y10T 428/31551 : Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31663 : As siloxane, silicone or silane
• CPC Class Codes: Y10T 428/31681 : Next to polyester, polyamide or polyimide [e.g., alkyd, glue, or nylon, etc.]
• CPC Class Codes: Y10T 428/31786 : Of polyester [e.g., alkyd, etc.]

Abstract

A gas-barrier laminate with a plastic substrate, an inorganic thin film formed on at least one surface of the plastic substrate, and a coating layer formed by applying a coating material on a surface of the inorganic thin film, wherein said coating layer contains a polyester-based resin having a molecular weight of 3000 to 15000 and a polyurethane-based resin having a molecular weight of 8000 to 30000 at a weight ratio of 5/95 to 95/5, and said gas-barrier laminate has an oxygen permeability of not more than 25 fmol/m²/s/Pa; and a gas-barrier laminate comprising a plastic substrate, an inorganic thin film formed on at least one surface of the plastic substrate, and a coating layer formed by applying a coating material on a surface of the inorganic thin film, wherein the gas-barrier laminate exhibits an oxygen permeability of not more than 50 fmol/m²/s/Pa as measured with respect to a gas-barrier film obtained by laminating an unstretched polypropylene film having a thickness of 60 μm on the coating layer of the gas-barrier laminate after subjecting the gas-barrier film to hydrothermal treatment at 120° C. for 30 min, and the coating layer has either a hardness of 0.1 to 0.5 GPa as measured at 23° C. in atmospheric air by a nano-indentation hardness testing method, a hardness of 0.03 to 0.5 GPa as measured at 23° C. in water by a nano-indentation hardness testing method, or a ratio of number of carbon atoms derived from carboxyl groups to number of carbon atoms constituting the surface of the coating layer of 0.005 to 0.1.

Claims

1. A gas-barrier laminate comprising a plastic substrate, an inorganic thin film formed on at least one surface of the plastic substrate, and a coating layer formed by applying a coating material on a surface of the inorganic thin film, said coating layer containing a polyester-based resin having a molecular weight of 3000 to 15000 and a polyurethane-based resin shaving a molecular weight of 8000 to 30000 at a weight ratio of 5/95 to 95/5, and said gas-barrier laminate having an oxygen permeability of not more than 25 fmol/m²/s/Pa.

2. A gas-barrier laminate according to claim 1, wherein the polyester-based resin and the polyurethane-based resin respectively have a glass transition temperature of 55 to 100°

C. and an acid value of 1 to 100 mgKOH/g.

3. A gas-barrier laminate according to claim 1, wherein the coating layer contains a silane coupling agent in an amount of 0.1 to 20% by weight.

4. A gas-barrier laminate according to claim 3, wherein the silane coupling agent is an epoxy group-containing silane coupling agent and/or an amino group-containing silane coupling agent.

5. A gas-barrier laminate according to any one of claim 1, wherein the coating material contains a fatty acid, a fatty ester, a fatty amide or a mixture thereof in an amount of 0.05 to 20 parts by weight based on 100 parts by weight of a sum of the polyester-based resin and the polyurethane-based resin.

6. A gas-barrier laminate according to any one of claim 1, wherein the coating material contains a polyisocyanate as a curing agent and a content of the polyisocyanate in the coating material is 0.8 to 1.5 times a total hydroxyl equivalent of the polyester-based resin and the polyurethane-based resin.

7. A gas-barrier laminate according to claim 6, wherein the polyisocyanate contains at least one compound having three or more active isocyanate group in a molecule thereof.

14. A gas-barrier laminate according to claim 1, wherein the plastic substrate comprises a polyester resin, a polyamide resin, a polyolefin resin, an ethylene-vinyl alcohol copolymer resin or a biodegradable resin.

15. A gas-barrier laminate according to claim 1, wherein the inorganic thin film is a physically vapor-deposited film or a chemically vapor-deposited film comprising silicon oxide, aluminum oxide, diamond-like carbon or a mixture thereof.

16. A gas-barrier laminate according to claim 1, further comprising an anchor coat layer disposed between the plastic substrate (A and the inorganic thin film.

17. A gas-barrier laminate according to claim 16, wherein the anchor coat layer is made of at least one resin selected from the group consisting of a polyester-based resin, an urethane-based resin, an acrylic resin, an alkoxysilyl group-containing resin, an oxazoline group-containing resin and copolymer resins thereof.

18. A gas-barrier laminate according to any claim 1, further comprising a printed layer formed on a surface of the coating layer, and a heat seal layer formed on a surface of the printed layer.

19. A gas-barrier laminate according to claim 18, further comprising at least one paper or plastic substrate disposed between the printed layer and the heat seal layer.

20. A gas-barrier laminate according to claim 19, wherein the plastic substrate disposed between the printed layer and the heat seal layer comprises a polyester-based resin, a polyamide-based resin, an ethylene-vinyl acetate copolymer resin or a mixture thereof.

21. A gas-barrier laminate according to claim 1, wherein the gas-barrier laminate is heat-treated at a temperature of not less than 60°

C.

22. A gas-barrier laminate according to claim 1, wherein when the gas-barrier laminate is subjected to hydrothermal treatment under pressure at 120°

C. for 30 min, an oxygen permeability of the gas-barrier laminate after being subjected to the hydrothermal treatment is not more than 25 fmol/m²/s/Pa.

23. A gas-barrier laminate according to claim 18, wherein when the gas-barrier laminate is subjected to hydrothermal treatment under pressure at 120°

C. for 30 min, an adhesion strength between the inorganic thin film and the coating layer is not less than 100 g/15 mm, and an adhesion strength between the coating layer and the printed layer is not less than 100 g/15 mm.

8. A gas-barrier laminate comprising a plastic substrate, an inorganic thin film formed on at least one surface of the plastic substrate, and a coating layer formed on a surface of the inorganic thin film, said coating layer having a hardness of 0.1 to 0.5 GPa as measured at 23°

C. in atmospheric air by a nano-indentation hardness testing method, and the gas-barrier laminate exhibiting an oxygen permeability of not more than 50 fmol/m²/s/Pa as measured with respect to a gas-barrier film obtained by laminating an unstretched polypropylene film having a thickness of 60 μ

m on the coating layer of the gas-barrier laminate after subjecting the gas-barrier film to hydrothermal treatment at 120°

C. for 30 min.

11. A gas-barrier laminate according to claim 8, wherein the ratio of number of carbon atoms derived from carboxyl groups to number of carbon atoms constituting the surface of the coating layer is 0.005 to 0.1.

12. A gas-barrier laminate according to claim 8, wherein the coating layer is made of at least one resin selected from the group consisting of a polyester-based resin, an urethane-based resin, an acrylic resin, an alkoxysilyl group-containing resin, an oxazoline group-containing resin and copolymer resins thereof.

13. A gas-barrier laminate according to claim 8, wherein a gas-barrier film obtained by forming a printed layer on the coating layer of the gas-barrier laminate and further laminating an unstretched polypropylene film having a thickness of 60 μ

m on the printed layer exhibits an oxygen permeability of not more than 50 fmol/m²/s/Pa after subjecting the gas-barrier film to hydrothermal treatment at 120°

C. for 30 min.

9. A gas-barrier laminate comprising a plastic substrate, an inorganic thin film formed on at least one surface of the plastic substrate, and a coating layer formed on a surface of the inorganic thin film, said coating layer Shaving a hardness of 0.03 to 0.5 GPa as measured at 23°

C. in water by a nano-indentation hardness testing method, and the gas-barrier laminate exhibiting an oxygen permeability of not more than 50 fmol/m²/s/Pa as measured with respect to a gas-barrier film obtained by laminating an unstretched polypropylene film having a thickness of 60 μ

m on the coating layer of the gas-barrier laminate after subjecting the gas-barrier film to hydrothermal treatment at 120°

C. for 30 min.

10. A gas-barrier laminate comprising a plastic substrate, an inorganic thin film formed on at least one surface of the plastic substrate, and a coating layer formed on a surface of the inorganic thin film, said coating layer having a ratio of number of carbon atoms derived from carboxyl groups to number of carbon atoms constituting the surface of the coating layer of 0.005 to 0.1, and the gas-barrier laminate exhibiting an oxygen permeability of not more than 50 fmol/m²/s/Pa as measured with respect to a gas-barrier film obtained by laminating an unstretched polypropylene film having a thickness of 60 μ

m on the coating layer of the gas-barrier laminate after subjecting the gas-barrier film to hydrothermal treatment at 120°

C. for 30 min.