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. 01, 1982
Filed:
Aug. 22, 1980
Takami Ishii, Ube, JP;
Naohisa Takikawa, Ube, JP;
Kiyoaki Tokunaga, Ube, JP;
Nobuhiro Ogawa, Ube, JP;
UBE Industries, Ltd., , JP;
Abstract
Undesirable deposition of polyoxymethylene onto the inner wall of a polymerization vessel and onto a stirrer, which deposition is observed in the slurry polymerization of formaldehyde carried out in an inert organic liquid medium in the presence of a polymerization catalyst, can be minimized by carrying out the slurry polymerization in the presence of at least one polyvalent metal salt selected from polyvalent metal salts of alkylsalicylic acids and polyvalent metal salts of dialkyl esters of sulfosuccinic acid. Optionally, a polyethylene glycol monoether may be used in addition to the polyvalent metal salt.