LAMINATED POLYESTER FILM FOR MAGNETIC RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a biaxially oriented laminated polyester film which is useful as a base film of a high-density magnetic recording medium having excellent electromagnetic transducing characteristics and extremely little dropout. SOLUTION: This laminated film consists of a base layer A comprised of a polyethylene terephthalate resin A, and a coating film layer B containing a binder resin, inert fine particles and a surfactant formed on the one surface of the base layer A. The base layer A consists of a biaxially oriented film having substantially no inert fine particles. The center line average roughness of the surface of the coating film layer B is <=5 nm. The density of large projections having >=10μm major diameter on the surface of the layer B is <=20 pieces/cm2.