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. 18, 1976
Filed:
Nov. 08, 1972
Applicant:
Inventors:
Haruo Miyamoto, Nagoya, JA;
Ikuo Igami, Tomei, JA;
Masaru Uehara, Nagoya, JA;
Hideo Fujita, Takarazuka, JA;
Hirotaka Itoh, Nishinomiya, JA;
Zyozi Kan, Niihama, JA;
Assignees:
Dainichi-Nippon Cables, Ltd., Amagasaki, JA;
Mitsubishi Rayon Co., Ltd., Tokyo, JA;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
D21H / ; D21H / ;
U.S. Cl.
CPC ...
162102 ; 100 38 ; 162138 ; 162146 ; 1621 / ; 1621 / ; 162206 ; 264121 ;
Abstract
Polyolefin fibers containing at least 70% by weight of polypropylene fibers having a denier of at least 0.5 and a birefringence of at least 2.5 .times. 10.sup.-.sup.2 are formed into a sheet. The sheet is then frictionally calendered in the dry state at a frictional ratio of at least 15% and at a temperature in the range from 90.degree.C to 160.degree.C whereby an insulating paper having excellent air-impermeability and oil-resistance is obtained.