BIAXIALLY ORIENTED POLYESTER FILM FOR MOLDING CONTAINER

摘要

PROBLEM TO BE SOLVED: To obtain the subject film not containing isophthalic acid component as an acid component, excellent in moldability as well as taste characteristics after retort and suitable for metal cans obtained by molding and processing by specifying melting point and carboxyl end group. SOLUTION: This polyester film has 240-300 deg.C melting point and 10-50 equivalent/ton carboxyl end group and does substantially not contain isophthalic acid as an acid component and has preferably >=1.50 refractive index. Furthermore, >=95wt.% of an unit of polyester is preferably an ethylene terephthalate unit and/or ethylene naphthalate unit and relaxation time of carbonyl part in a structural analysis is preferably >=270m sec.