Laminate having oxygen barrier properties and packaging material comprising laminate
The invention provides a laminate having excellent oxygen barrier properties and excellent flex resistance, and a packaging material comprising the laminate. A laminate having at least a substrate layer, an adhesive layer, a barrier layer and a sealant layer, and a packaging material comprising the laminate, wherein the adhesive layer is a layer having oxygen barrier properties.
1. A packaging material comprising a laminate having at least a substrate layer, an adhesive layer, a barrier layer, and a sealant layer,
wherein the adhesive layer has oxygen barrier properties,
the adhesive layer includes at least one resin selected from the group consisting of (A) a resin having two or more hydroxyl groups in the molecule as functional groups, (B) a resin having an isocyanate compound having two or more isocyanate groups in the molecule as functional groups, and (C) a resin having a specific phosphoric acid-modified compound,
a main backbone of the at least one resin is selected from the group consisting of polyester, polyester-polyurethane, polyether, and polyether-polyurethane, and
the barrier layer is present between the sealant layer and the adhesive layer and comprises an inorganic material.
2. The packaging material according to claim 1 , wherein the barrier layer is an aluminum vapor deposition film.
3. The packaging material according to claim 1 , wherein the thickness of the barrier layer is 1 to 100 nm.
4. The packaging material according to claim 1 , wherein the coating amount of the adhesive of the adhesive layer is 2.0 μm to 4.0 μm.
5. The packaging material according to claim 1 , wherein an oxygen permeability of the laminate in an environment of 23° C., 90% RH is 0.05 to 1.00 cc/m 2 ·day·atm.
6. The packaging material according to claim 1 , wherein after the laminate has been subjected to a flexural load 3 times with a Gelbo Flex Tester, an increase in an oxygen permeability of the laminate in an environment of 23° C., 90% RH compared to before being subjected to the flexural load is 0.7 to 4.0 cc/m 2 ·day·atm.
7. The packaging material according to claim 1 , wherein the inorganic material is an inorganic oxide.
8. The packaging material according to claim 1 , further comprising a vapor deposition layer and a barrier coat layer, wherein the vapor deposition layer and the barrier coat layer are disposed between the substrate layer and the adhesive layer.
9. The packaging material according to claim 8 , further comprising a printing layer, wherein the printing layer is disposed between the barrier coat layer and the adhesive layer.
10. The packaging material according to claim 8 , wherein the vapor deposition layer is composed of an aluminum vapor deposition film, an alumina vapor deposition film, or a silica vapor deposition film.
11. The packaging material according to claim 1 , wherein the adhesive layer, the barrier layer, and the sealant layer are disposed on one side of the substrate layer, the adhesive layer being the closest to the substrate layer.
12. The packaging material according to claim 11 , wherein a surface of the barrier layer has recesses of irregularities, and the recesses are filled by the at least one resin in the adhesive layer.
13. The packaging material according to claim 11 , further comprising a vapor deposition layer and a barrier coat layer, wherein the vapor deposition layer and the barrier coat layer are disposed between the substrate layer and the adhesive layer.
14. The packaging material according to claim 13 , wherein the barrier coat layer is disposed adjacent to the adhesive layer.
15. The packaging material according to claim 14 , further comprising a printing layer, wherein the printing layer is disposed between the barrier coat layer and the adhesive layer.
16. The packaging material according to claim 13 , further comprising a printing layer, wherein the printing layer is disposed between the barrier coat layer and the adhesive layer.