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. 13, 2021
Filed:
Mar. 13, 2017
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Thai Polyacetal Co., Ltd, Bangkok, TH;
Yuuta Yamamoto, Mie, JP;
Daisuke Sunaga, Mie, JP;
Akira Ito, Tokyo, JP;
Wandee Thuamthong, Rayong, TH;
Yupin Pattamamongkolchai, Rayong, TH;
MITSUBISHI GAS CHEMICAL COMPANY, INC., Tokyo, JP;
THAI POLYACETAL CO., LTD., Bangkok, TH;
Abstract
The present invention is to provide a process for producing an oxymethylene copolymer, in which deteriorate due to oxidation hardly occurs, an amount of formaldehyde generated from the product when stored for a long time under environment of high temperature and high humidity is reduced, and occurrence of mold deposit during molding is small. A process for producing an oxymethylene copolymer includes Step 1 of polymerizing polymer raw materials containing trioxane and a comonomer in the presence of a specific amount of an acid catalyst, Step 2 of adding a hydroxylamine compound represented by the following general formula (1): to a product obtained in the Step 1 in an amount of 1 to 20-fold mol based on an amount of the acid catalyst and mixing these, andStep 3 of further melting and kneading a mixture of the product and the hydroxylamine compound obtained in the Step 2.