SUBSTRATE FILM FOR PRODUCING PLASTIC FILM

摘要

PROBLEM TO BE SOLVED: To provide a polyester substrate film which can very highly satisfy surface evenness and transparency of a formed film obtained when the polyester substrate film is used as a substrate film for producing a plastic film by a method such as casting and has good quality and operating efficiency in the process. SOLUTION: In the polyester substrate film used as a substrate in the process for forming a plastic film, the amount of oligomer on one of the surfaces thereof is 5.0 mg/m2or less when it is measured after methyl ethyl ketone is applied to the film surface followed by drying and heat-treatment at 180°C for 10 minutes; the Ra of the film surface is in the range of 5.0 to 10 nm; and the density of the film is in the range of 1.405 to 1.415 g/cm3. COPYRIGHT: (C)2009,JPO&INPIT