Gas-barrier laminate and packaging bag
Provided is a gas barrier laminate including: a paper substrate; an anchor coat layer including a first polyolefin having a polar group; a vapor-deposited layer; and an overcoat layer including a second polyolefin having a polar group, in order, in which the gas barrier laminate includes a layer including a polyvinyl alcohol-based resin between the paper substrate and the anchor coat layer or between the anchor coat layer and the vapor-deposited layer.
1. A gas barrier laminate comprising, in following order:
a paper substrate;
an anchor coat layer including a first polyolefin having a polar group;
a vapor-deposited layer; and
an overcoat layer including a second polyolefin having a polar group,
wherein the gas barrier laminate further comprises a resin layer that includes a polyvinyl alcohol-based resin between the paper substrate and the anchor coat layer or between the anchor coat layer and the vapor-deposited layer, and
wherein a thickness of the anchor coat layer is 1 μm or more and 5 μm or less, and a thickness of the resin layer is 1 μm or more and 5 μm or less.
2. The gas barrier laminate according to claim 1 , wherein the first polyolefin having a polar group has at least one selected from a carboxyl group, a salt of a carboxyl group, a carboxylic acid anhydride group, and a carboxylic acid ester.
3. The gas barrier laminate according to claim 1 , wherein the second polyolefin having a polar group has at least one selected from a carboxyl group, a salt of a carboxyl group, a carboxylic acid anhydride group, and a carboxylic acid ester.
4. The gas barrier laminate according to claim 1 , wherein the first polyolefin having a polar group is a copolymer of an acrylic acid ester and maleic anhydride.
5. The gas barrier laminate according to claim 1 , wherein the first polyolefin having a polar group is an ethylene-vinyl acetate copolymer.
6. The gas barrier laminate according to claim 1 , wherein the first polyolefin having a polar group is an ethylene-glycidyl methacrylate copolymer.
7. The gas barrier laminate according to claim 1 , wherein the second polyolefin having a polar group is a copolymer of an acrylic acid ester and maleic anhydride.
8. The gas barrier laminate according to claim 1 , wherein the second polyolefin having a polar group is an ethylene-vinyl acetate copolymer.
9. The gas barrier laminate according to claim 1 , wherein the second polyolefin having a polar group is an ethylene-glycidyl methacrylate copolymer.
10. The gas barrier laminate according to claim 1 , wherein a thickness of the vapor-deposited layer is 30 nm or more and 100 nm or less.
11. The gas barrier laminate according to claim 1 , wherein a thickness of the overcoat layer is 2 μm or more and 10 μm or less.
12. The gas barrier laminate according to claim 1 , wherein a thickness of the paper substrate is 30 μm or more and 100 μm or less, and the thickness of the paper substrate is 70% or more of a thickness of the entire gas barrier laminate.
13. The gas barrier laminate according to claim 1 , wherein a weight of paper is 50% by mass or more based on the entire gas barrier laminate.
14. A packaging bag comprising the gas barrier laminate according to claim 1 .
15. The packaging bag according to claim 14 , having a folding part.
16. A gas barrier laminate comprising, in following order:
a paper substrate;
a resin layer including a polyvinyl alcohol-based resin;
an anchor coat layer including a first polyolefin having a polar group;
a vapor-deposited layer; and
an overcoat layer including a second polyolefin having a polar group,
wherein a thickness of the anchor coat layer is 1 μm or more and 5 μm or less, and a thickness of the resin layer is 1 μm or more and 5 μm or less,
wherein the resin layer has a first surface that contacts the paper substrate and a second surface that contacts the anchor coat layer, and
wherein the anchor coat layer has a first surface that contacts the resin layer and a second surface that contacts the vapor-deposited layer.
17. A gas barrier laminate comprising, in following order:
a paper substrate;
an anchor coat layer including a first polyolefin having a polar group;
a resin layer including a polyvinyl alcohol-based resin;
a vapor-deposited layer; and
an overcoat layer including a second polyolefin having a polar group,
wherein a thickness of the anchor coat layer is 1 μm or more and 5 μm or less, and a thickness of the resin layer is 1 μm or more and 5 μm or less,
wherein the anchor coat layer has a first surface that contacts the paper substrate and a second surface that contacts the resin layer, and
wherein the resin layer has a first surface that contacts the anchor coat layer and a second surface that contacts the vapor-deposited layer.