| 摘要 |
PURPOSE:To improve sliding properties of a film, element winding properties and impregnation properties of insulating oil by providing a rough face with granular projections on the surface of a film and also providing a rough face of mesh structure on the other face. CONSTITUTION:Both faces of a film are roughened, and one face is a rough face of mesh structure with 0.025mum-0.15mum surface roughness Ra and with 10 to 30 projections per mm of 0.0125mum or over formed thereon, while the other face is provided with granular projections, and a film for an oil impregnated type capacitor of 0.05mum-0.3mum surface roughness Ra and with 10 to 40 projections per mm of 0.025mum height formed thereon is formed. The film roughened on its both faces is composed, for example, of an ethylene propylene copolymer and can be manufactured by laminating a composite layer with independent granular projections on its surface and a base layer of polypropylene with mesh structure surface. |
