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:
Jun. 28, 2016
Filed:
Apr. 16, 2012
Shinya Higuchi, Tokyo, JP;
Yasuhiko Matsuoka, Tokyo, JP;
Shigeki Kobayashi, Tokyo, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
To produce a PTFE aqueous emulsion, whereby the environmental load is little, the stability of the aqueous emulsion is high, and a molded product having high heat resistance can be obtained. A process for producing a PTFE aqueous emulsion, which comprises emulsion-polymerizing tetrafluoroethylene (TFE) by means of at least one fluorinated emulsifier selected from the group consisting of a Cfluorinated carboxylic acid having from 1 to 4 etheric oxygen atoms in its main chain, and its salts, to obtain an aqueous emulsion containing polytetrafluoroethylene (PTFE) microparticles having an average primary particle size of from 0.1 to 0.3 μm, wherein at the beginning of the emulsion polymerization of TFE, a (polyfluoroalkyl)ethylene (a) represented by 'CH═CH—Rf', and/or a comonomer (b) having a monomer reactivity ratio rof from 0.1 to 8 in copolymerization with tetrafluoroethylene, is incorporated to the emulsion polymerization system, so as to be from 0.001 to 0.01 mass % relative to the final amount of polytetrafluoroethylene produced.