| 摘要 |
PURPOSE:To provide the polyester film excellent in shaving resistance and scratch resistance and reducing the abrasion of a slit blade at the time of processing. CONSTITUTION:In a biaxially oriented laminated polyester film for a magnetic recording medium wherein a polyester layer A is laminated on the single surface or both surfaces of a polyester layer B, the polyester layer A contains 0.1-1.0wt.% of theta-type aluminum oxide particles with a specific surface are a of 50-120m<2>/g, a total pore volume of 0.5-1.0m/g and a mean particle size of 0.02-0.3mum and one or more kind of inert particles with a mean particle size of 0.3-1.2mum. The thickness of the polyester layer A or the sum thickness of the polyester layers A is 3-30% of the total thickness of the laminated film and the content per a unit wt. of theta-type aluminum oxide particles in the total thickness is below 0.1wt.%. |
