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:
Dec. 15, 1992
Filed:
Nov. 22, 1989
Applicant:
Inventors:
Akira Ueno, Yokohama, JP;
Mayumi Takata, Tokyo, JP;
Naoki Yamazaki, Tokyo, JP;
Syoiti Sugaya, Tokyo, JP;
Assignee:
Daito Communication Apparatus Co. Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08K / ;
U.S. Cl.
CPC ...
524495 ; 524496 ; 252511 ; 423460 ; 502432 ;
Abstract
A product having a positive temperature coefficient of resistance is formed by etching a carbon black at an elevated temperature to remove less crystalline portions and thereby to increase the specific surface area of the carbon black. The resulting carbon black is called porous carbon black. The porous carbon black is blended with a crystalline polymer to form a product having the desired positive temperature coefficient of resistance. Production of a material suitable for use as a resettable fuse is described.