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:
May. 01, 1990
Filed:
Nov. 02, 1988
Applicant:
Inventors:
Mari Aoyama, Okazaki, JP;
Michiyasu Ito, Kuwana, JP;
Syoichi Tsuji, Nagoya, JP;
Toshiyuki Ishii, Kasugai, JP;
Tomohide Tanaka, Nagoya, JP;
Assignee:
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29C / ; B29C / ;
U.S. Cl.
CPC ...
264 41 ; 2642106 ; 2642107 ; 264284 ; 2642888 ; 2642896 ; 264D / ;
Abstract
A gas-permeable porous film which is prepared by stretching a film made from a mixture containing a polyolefin resin and an inorganic filler at least uniaxially and possesses a rugged pattern on its surface. One process for producing the film comprises forming the aforesaid mixture into a film, providing on the surface of the film a rugged pattern, stretching the resulting film at least uniaxially, and forming on the stretched film thus-formed a rugged pattern by means of a heated emboss roll and simultaneously allowing the stretched film to contract.