Porous film excellent in flexibility

Abstract

Abstract PURPOSE:To obtain porous film rich in flexibility, excellent in gas permeability and improved in tear resistance by a method wherein the film obtained by melting, extruding polyolefin resin composite containing filler is stretched biaxially to give specified physical properties. CONSTITUTION:The thickness of the film is 45mum max., the average diameters of fine holes measured by a mercury porosimeter are scattered in the range of 0.05-5mum, the hole volume per unit volume 1cm<3> of the film is 0.1cc min., and the moisture permeability is 500g/m<2>.24hr min., the Elmendorf tear strength is 15kg.cm/cm<2> min. in the longitudinal direction of the film and both the longitudinal and the transverse stiffness satisfy formula ( I ). This porous film is obtained when the film obtained by melting and extruding the composite composed of 100wt. parts of polyolefin resin, 25-400wt. parts of fillers, and 1-100wt. parts of liquid or wax hydrocarbon or mixture composed of hydrocarbon polymer and epoxy base contained organic chemical is stretched biaxially.

Inventors

• 👤 Shoji Kumazaki
• 👤 熊崎　昌治
• 👤 Katsuhiro Kawabata
• 👤 川畑　克博
• 👤 Masahiro Morita
• 👤 森田　正広
• 👤 Yu Suzuki
• 👤 祐 鈴木

Bibliographic Details