US 12,275,567 B2
Gas barrier laminate and packaging bag
Junichi Kaminaga, Tokyo (JP); Yoshiki Koshiyama, Tokyo (JP); Yumiko Kojima, Tokyo (JP); and Rika Ishii, Tokyo (JP)
Assigned to TOPPAN Holdings Inc., Tokyo (JP)
Appl. No. 18/246,921
Filed by TOPPAN Holdings Inc., Tokyo (JP)
PCT Filed Sep. 29, 2021, PCT No. PCT/JP2021/035873
§ 371(c)(1), (2) Date Mar. 28, 2023,
PCT Pub. No. WO2022/071398, PCT Pub. Date Apr. 7, 2022.
Claims priority of application No. 2020-165032 (JP), filed on Sep. 30, 2020.
Prior Publication US 2023/0356904 A1, Nov. 9, 2023
Int. Cl. B65D 65/40 (2006.01); B65D 30/08 (2006.01)
CPC B65D 65/40 (2013.01) [B65D 31/02 (2013.01); B65D 2565/387 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A gas barrier laminate being capable of hermetic sealing by heat sealing, the gas barrier laminate comprising:
a paper substrate;
a first resin layer including a first polyolefin resin; and
a vapor-deposited layer disposed between the paper substrate and the first resin layer,
wherein the paper substrate has a basis weight of 30 to 100 g/m2;
a water vapor transmission rate is 3 g/m2 day or less at 40° C. and 90% RH;
the water vapor transmission rate obtained by folding the gas barrier laminate with the paper substrate placed on an outer side, rolling a roller having a weight of 2 kg thereon one time, opening a fold, and making measurement, is 4 g/m2 day or less at 40° C. and 90% RH, and the water vapor transmission rate obtained by folding the gas barrier laminate with the paper substrate placed on an inner side, rolling a roller having a weight of 2 kg thereon one time, opening a fold, and making measurement, is 4 g/m2-day or less at 40° C. and 90% RH;
a weight of the paper substrate is 47% by mass or more with respect to a gross weight of the gas barrier laminate;
the first resin layer has a first surface and a second surface, and the first surface faces the vapor-deposited layer and the second surface constitutes a surface of the gas barrier laminate; and
the first polyolefin resin 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.