Abstract: Disclosed is a sealant film including at least a layer formed of a polyester as a superficial layer, in which the polyester contains 20 to 50 mol % of a 2,5-furandicarboxylic acid unit, 18 to 49.5 mol % of at least one diol unit selected from the group consisting of an ethylene glycol unit, a 1,3-propanediol unit, and a 1,4-butanediol unit, and 0.5 to 2.5 mol % of a diethylene glycol unit, the sealant film has a crystallinity of less than 14%, and the sealant film is a stretched film that exhibits a shrinkage ratio of 6% or more in a maximum shrinkage direction upon being allowed to stand at 125° C. for 20 seconds. This provides a sealant film superior in mechanical properties, especially tensile elongation, and also superior in heat sealability, non-adsorptivity, and gas barrier properties.

Abstract: Disclosed is a sealant film including at least a layer formed of a polyester as a superficial layer, in which the polyester contains 20 to 50 mol % of a 2,5-furandicarboxylic acid unit, 18 to 49.5 mol % of at least one diol unit selected from the group consisting of an ethylene glycol unit, a 1,3-propanediol unit, and a 1,4-butanediol unit, and 0.5 to 2.5 mol % of a diethylene glycol unit, the sealant film has a crystallinity of less than 14%, and the sealant film is a stretched film that exhibits a shrinkage ratio of 6% or more in a maximum shrinkage direction upon being allowed to stand at 125° C. for 20 seconds. This provides a sealant film superior in mechanical properties, especially tensile elongation, and also superior in heat sealability, non-adsorptivity, and gas barrier properties.