TREATING AGENT FOR PRODUCING ALUMINUM-DEPOSITED POLYESTER FILM, METHOD OF PRODUCING ALUMINUM-DEPOSITED POLYESTER FILM, AND FILM FOR PACKAGING

摘要

PROBLEM TO BE SOLVED: To provide a treating agent for an aluminum-deposited polyester film which can be rendered into a multilayered film for packaging excellent in appearance and adhesion.SOLUTION: A treating agent comprising a polyester resin composed of the following constitutional units A-D and having a number average molecular weight of 5,000 to 15,000, and an oxazoline-based crosslinking agent is used. The constitutional unit A is a constitutional unit formed from one or two or more selected from the group consisting of a C8-C12 aromatic dicarboxylic acid and a derivative thereof, and a C4-C22 aliphatic dicarboxylic acid and a derivative thereof. The constitutional unit B is a constitutional unit formed from a C9-C20 trivalent or tetravalent aromatic polycarboxylic acid. The constitutional unit C is a constitutional unit formed from a C2-C10 alkanediol. The constitutional unit D is a constitutional unit formed from a diol compound represented by the following formula where Xis a residue obtained by removing all hydroxyl groups from a polybutylene glycol having a polyoxybutylene group composed of 2-30 oxybutylene units.