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:
Feb. 18, 1992
Filed:
Jan. 29, 1991
Applicant:
Inventors:
Assignee:
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08F / ;
U.S. Cl.
CPC ...
502158 ; 502164 ;
Abstract
The process of producing a catalyst for polymerization of organosiloxanes comprises heat-treating a mixture of an aqueous solution of a tetraalkylphosphonium hydroxide, such as tetramethylphosphonium hydroxide, and a cyclic or noncyclic siloxane component, thereby controlling the water content of the system so that the molar ratio of the amount of water in the system to the amount of the quaternary phosphonium hydroxide component in the system will be from 3.0 to 4.0. The process ensures that the crystallization of the tetraalkylphosphonium hydroxide component in the catalyst is obviated effectively.