POLYESTER RESIN COMPOSITION FOR STRETCHED FILM

摘要

PROBLEM TO BE SOLVED: To provide a polyester resin composition for a stretched film, which has such properties that in a melt film-forming process of a white polyester film, a laminate capable of reliably forming a uniform gap can be obtained simply by co-extrusion of the composition into a surface layer, and that a portion of the film not used for the product can be collected and reused.SOLUTION: The polyester resin composition contains porous silica particles by 0.1 to 10 mass%. The porous silica particles have a secondary particle diameter of 10μm or more and 100μm or less, and show a compression rate of 30% or more under 0.1 gf load and a compression rate of 25% or less under 0.05 gf load. The resin composition contains a phosphorus compound by 50 to 150 mmol% in terms of an amount of phosphorus elements based on a molar number of whole acid components in the polyester.