Laminate body and packaging bag using the same

A laminate body having at least three different layers, wherein

• the at least three different layers comprise a heat resistant layer, a heat-sealing layer, and an inorganic thin film layer,
• the laminate body has a thickness of 3 μm to 200 μm;
• the heat-sealing layer is at least one of the outermost layers of the laminate body,
• the heat-sealing layer includes a polyester component containing ethylene terephthalate as a main constituent, and first additional monomers other than terephthalic acid and ethylene glycol, which constitute the ethylene terephthalate, in an amount of 32 mol % to 50 mol %, wherein the first additional monomers are selected from (i) isophthalic acid and/or (ii) at least one of neopentyl glycol, 1,4-cyclohexanedimethanol, 1,4-butanediol, and diethylene glycol,
• the heat-sealing layer constitutes 20% to 80% of the total thickness of the laminate body,
• the heat resistant layer includes a polyester component containing ethylene terephthalate as a main constituent and second additional monomers other than terephthalic acid and ethylene glycol, which constitute the ethylene terephthalate, in an amount of 9 mol % to 20 mol %, wherein the second additional monomers are selected from (i) a dicarboxylic acid monomer and/or (ii) a diol monomer,
• the heat resistant layer contains the largest amount of ethylene terephthalate of the at least three different layers,
• the heat resistant layer constitutes 20% to 80% of the total thickness of the laminate body,
• the inorganic thin film layer comprises an inorganic acid selected from silicon oxide, aluminum oxide, and aluminum as a main component,
• the inorganic thin film layer has a thickness of 2 nm to 100 nm,
• when sealing is performed by bonding the heat-sealing layer together at 140° C. and 0.2 MPa for 2 seconds, the laminate body provides a sealing strength of 8 N/15 mm or more and 30 N/15 mm or less,
• the laminate body has a water vapor permeation rate of 0.1 g/m2·d or more and 6 g/m2·d or less under an atmosphere at a temperature of 40° C. and a relative humidity of 90% RH,
• the laminate body has an oxygen permeation rate of 5 ml/m2·d·MPa or more and 30 ml/m2·d·MPa or less under an atmosphere at a temperature of 23° C. and a relative humidity of 65% RH, and
• the laminate body has a heat shrinkage rate, after immersion in hot water at 98° C. for 3 minutes, of −5% or more and 5% or less in each of the longitudinal direction and the width direction.