| 摘要 |
PURPOSE:To provide a biaxially oriented polyester film for a magnetic recording medium having improved slip properties, cutting resistance and scratch resistance. CONSTITUTION:A biaxially oriented polyester film is manufactured in such a manner that spindle calcium carbonate specified by a particle size ratio, mean particle size and a relative standard deviation and one kind or more of fine particles selected from aluminum oxide, silicon oxide and titanium oxide specified by a specific surface area, overall pore volume and means particle size are contained in said polyester at specific ratios, the projection distribution of the surface of the film by these particles has specific relationship and the increase of a travelling friction coefficient (OMEGAmuk) is less than 0.15. |
