PROCESS FOR PREPARING POLYESTER FILM

摘要

The invention provides a process for the production of polyester film which is useful for magnetic cards. The process comprises the steps of: adding 60-80% by weight of titanium compound (based on the polymer) and 0.005-0.1% by weight of cobalt acetate (based on the titanium) to polyethylene terephthalate polymer; compounding the mixture to make high concentrated master chips; mixing the chips with polyethylene terephthalate; drying and molding the final mixture. The polyester film has a limited viscosity of 0.4-0.9dl/g and is at least uniaxially oriented.