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. 22, 1987
Filed:
Apr. 29, 1986
Applicant:
Inventors:
Assignee:
Daikin Kogyo Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08F / ;
U.S. Cl.
CPC ...
526255 ; 524546 ;
Abstract
Polytetrafluoroethylne fine powder is disclosed having an average molecular weight of at least 6,000,000, an amorphous index larger than 0.1 and a number average primary particle size of 0.1 to 0.8 micron, and further having a clear endothermic peak at a temperature of 347.degree..+-.3.degree. C. and another endothermic peak or shoulder at a temperature between 330.degree. C. and the temperature of said clear endothermic peak on a crystalline melting chart recorded by a differential scanning calorimeter. An unsintered article is made which is sintered and expanded at a temperature higher than the melting point of the polytetrafluoroethylene to give a porous article having improved properties.