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:
Aug. 28, 2012
Filed:
Apr. 03, 2009
Takayoshi Sano, Fuji, JP;
Satoru Nitta, Numazu, JP;
Takayoshi Sano, Fuji, JP;
Satoru Nitta, Numazu, JP;
Toshiba Kikai Kabushiki Kaisha, Tokyo, JP;
Abstract
Provided is a method for manufacturing a high-quality porous film. Here, while the porous film is being manufactured through forming micropores by stretching, a raw film is prevented from slipping on the surfaces of the respective rolls as much as possible even though the raw film includes oil or liquid paraffin as a solvent. The method is for manufacturing a porous film through forming micropores by successive biaxial stretching. A tensile force applied to the raw film F transferring from the longitudinal stretching machine () to the transverse stretching machine () is set not less than a stretching force necessary for the longitudinal stretching, and thus the raw film is prevented from slipping on a contact surface between the raw film and each roll of the longitudinal stretching machine ().