The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 27, 2004
Filed:
Oct. 31, 2001
Kazuyuki Hada, Tokuyama, JP;
Yoshinori Takahashi, Tokuyama, JP;
Tokuyama Corporation, Tokuyama, JP;
Abstract
The present invention provides a porous polyolefin film abounding in air permeability and moisture permeability and having extremely high degree of light transmission and tear strength, a process for producing same and intended use thereof. This porous polyolefin film is produced, for example, by stretching an unstretched polyolefin film having a resin composition of 100 parts by weight of polyolefin, 50-150 parts by weight of an inorganic filler having a 50% median diameter of at least 2 &mgr;m but less than 7 &mgr;m measured according to the light-scattering method, and 2-20 parts by weight of a wax of polyolefin series in at least uniaxial direction at an area magnification of 1.1-1.5 times, and possesses physical properties of a water vapor transmission rate of at least 1000 g/m ·24 hrs., a light transmission of at least 65%, and a tear strength of at least 0.6 N.