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:
May. 31, 2005
Filed:
Oct. 29, 2002
Takashi Tomita, Toyonaka, JP;
Tsutomu Yuasa, Osaka, JP;
Hirokatsu Kawakami, Izumiotsu, JP;
Nippon Shokubai Co., Ltd., Osaka, JP;
Abstract
There is provided: a (meth)acrylic acid (salt) polymer which has high properties and is little colored; and a process which can produce this polymer with a high polymerization conversion without causing the corrosion of the reaction vessel. When a (meth)acrylic acid (salt) polymer is obtained by carrying out polymerization of an unsaturated monocarboxylic monomer (a) and an unsaturated polyalkylene glycolic monomer (b) with a polymerization initiator, either a redox polymerization initiator including hydrogen peroxide and a reducing agent is used as the polymerization initiator in a specific amount, or the unsaturated polyalkylene glycolic monomer is subjected to the polymerization in the form of an esterification reaction product as obtained by a process including the steps of: esterifying the unsaturated monocarboxylic monomer and a polyalkylene glycol in a specific charging ratio in the presence of an acid catalyst in a manner for a portion of the residual unsaturated monocarboxylic monomer as a starting raw material to remain; and then neutralizing the acid catalyst and the residual unsaturated monocarboxylic monomer (a) with a basic substance after the esterification; and the polymerization is carried out under conditions where the pH during the polymerization is in the range of 3.2 to 7.0.