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:
Dec. 26, 2000
Filed:
May. 21, 1998
Nippon Shokubai Co., Ltd., Osaka, JP;
Abstract
The invention provides: a cement admixture which has excellent cement dispersibility and can afford high slump retainability; and a cement composition which has excellent cement dispersibility and high slump retainability. The cement admixture comprises a polycarboxylic acid as an effective component, wherein the polycarboxylic acid is obtained by a process including the steps of: charging 'a' parts by weight of a polyalkylene glycol (A) and 'b' parts by weight of a (meth)acrylic acid monomer (B) into a reactor in the range of {(a/n.sup.1/2)/b}.times.100.ltoreq.200, wherein n is an average molar number of the added oxyalkylene groups in the polyalkylene glycol (A) and is a number of 1 to 300; carrying out an esterification reaction of the resultant mixture in the reactor, thus obtaining a polyalkylene glycol (meth)acrylate (C); and copolymerizing the resultant polyalkylene glycol (meth)acrylate (C) and the (meth)acrylic acid monomer (B), thus obtaining the polycarboxylic acid.