co-injection molding and co-injection molding method

摘要

PROBLEM TO BE SOLVED: To provide a multilayer structure excellent in appearance with good productivity even by such a molding method as a coinjection molding method in which exposure of an EVOH resin to high temperature cannot be avoided.SOLUTION: In coinjection molding, a resin composition containing (A) an ethylene-vinyl ester copolymer saponification product and (B) a complete or partial dehydration product of a polyvalent metal sulfate hydrate are used. Since the resin composition is excellent in thermal stability at high temperature and the decomposition and expansion of the EVOH resin are suppressed, a molded article excellent in appearance can be obtained with good productivity by a coinjection molding method.