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:
Jul. 21, 1992
Filed:
Feb. 07, 1991
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
An improvement is proposed for decreasing triboelectric static charging of a polyvinyl chloride resin powder so as to improve the flowability of the powder and prevent a decrease in the bulk density of the powder due to static electricity. The improvement comprises, in the polymerization process of vinyl chloride monomer in an aqueous medium, adding, to the aqueous polymerization mixture, a specified amount of an aqueous dispersion containing a salt of a long-chain carboxylic acid with a divalent metal and an ester of sorbitan with a long-chain carboxylic acid in a specified weight proportion and in a specified total concentration at a moment when conversion of the monomer to polymer is at least 70%.