Biaxial orientierter Mehrschichtfilm aus Polyester

摘要

A biaxially oriented laminate polyester film consisting of a polyester layer A containing lubricant particles I and II and a polyester layer B laminated on one side of the polyester A, wherein the lubricant particles I and II contain non-agglomerated particles in a proportion of 80 to 100 %; the lubricant particles I have an average particle diameter of 0.3 to 1.0 mu m and are contained in an amount of 0.005 % by weight or more but less than 0.1 % by weight; the lubricant particles II have an average particle diameter which satisfies the following expression (1): $wherein\; dI\; is\; an\; average\; particle\; diameter\; of\; the\; lubricant\; particles\; I\; and\; dII\; is\; an\; average\; particle\; diameter\; of\; the\; lubricant\; particles\; II,\; and\; are\; contained\; in\; an\; amount\; of\; 0.1\; \%\; by\; weight\; or\; more\; but\; less\; than\; 1.0\; \%\; by\; weight.\; This\; biaxially\; oriented\; laminate\; polyester\; film\; has\; excellent\; flatness,\; scraping\; resistance\; and\; take-up\; property\; and\; is\; useful\; as\; a\; base\; film\; for\; a\; magnetic\; recording\; medium.$