PRODUCTION OF POLYESTER-BASED RESIN FOAM

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a polyester-based resin foam without producing injurious crease or crack when a foaming sheet is molded into the form. SOLUTION: A polyester-based resin foaming sheet containing a polyester- based resin as a substrate resin, having 0.5-3mm thickness and <=13% average crystallinity and <=3% difference between crystallinity of either one surface layer of the sheet and crystallinity of the other surface layer and <=3% difference between the crystallinity of center layer of the sheet and crystallinity of the each surface layer is heated to carry out secondary foaming and then molded in heated mold to raise the average crystallinity of the resin foam to >=20%.