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:
Apr. 07, 2009
Filed:
May. 01, 2006
Jun Hoshikawa, Ichihara, JP;
Shinya Higuchi, Ichihara, JP;
Yasuhiko Matsuoka, Ichihara, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
To obtain a high concentration aqueous PTFE dispersion containing PTFE at a concentration of from 60 to 75 mass % by dissolving from 0.001 to 0.1 mass %, based on the mass of PTFE, of a specific carboxylic acid salt such as ammonium laurate in a low concentration aqueous dispersion of polytetrafluoroethylene (PTFE) comprising from 1 to 40 mass % of PTFE fine particles, from 0.0001 to 0.02 mass %, based on the mass of PTFE, of a specific fluorine-containing carboxylic acid type emulsifier (for example, ammonium perfluorooctanoate), and from 1 to 20 mass %, based on the mass of PTFE, of a specific nonionic surfactant, and then concentrating the low concentration aqueous dispersion of PTFE. The present invention provides a process for producing a high concentration aqueous PTFE dispersion containing PTFE at a high concentration by using, as a starting material, a low concentration aqueous dispersion of PTFE containing a fluorine-containing carboxylic acid type emulsifier (PFCA) at a low concentration, and an aqueous PTFE dispersion obtained from the high concentration aqueous PTFE dispersion.