| 摘要 |
PROBLEM TO BE SOLVED: To provide a white film which can satisfy various characteristics required for a magnetic recording medium such as a magnetic recording card with good balance. SOLUTION: A film which has a laminated structure with at least two layers and consists of polyester resins contg. titanium oxide particles and satisfies conditions (1)-(6) is provided; (1) the content of titanium oxide particles in each layer is 6-35wt.%., (2) the differences in intrinsic viscosities between layers are at most 0.3, (3) the surface roughness Ra of at least one face is 0.005-0.3μm, (4) the tear strength is at least 300g/mm, (5) the whiteness is at least 85% (in terms of thickness of 188μm) and (6) the optical density (in terms of thickness of 188μm) is at least 1.
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