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:
Mar. 14, 2017
Filed:
Sep. 28, 2007
Shigeru Sakamoto, Himeji, JP;
Yoshio Irie, Himeji, JP;
Hiroyuki Ikeuchi, Himeji, JP;
Makoto Nagasawa, Himeji, JP;
Kunihiko Ishizaki, Suita, JP;
Sayaka Machida, Kobe, JP;
Shigeru Sakamoto, Himeji, JP;
Yoshio Irie, Himeji, JP;
Hiroyuki Ikeuchi, Himeji, JP;
Makoto Nagasawa, Himeji, JP;
Kunihiko Ishizaki, Suita, JP;
Sayaka Machida, Kobe, JP;
Nippon Shokubai Co., Ltd., Osaka, JP;
Abstract
The present invention provides a method for producing a water absorbent resin particle, in high productivity, not only in a controlled manner of particle size but also enhancing fundamental property (absorption capacity or absorption capacity against pressure) of a water absorbent resin. A method for producing a water absorbent resin particle having the cross-linking polymerization step for an aqueous solution of an unsaturated monomer; the grain refining step for water-swellable, water-containing gel-like cross-linked polymer (a) obtained in the cross-linking polymerization step; the drying step for grain refined gel; and the crushing step for a dried substance, wherein, in the grain refining step for the water-swellable, water-containing gel-like cross-linked polymer (a), water-swellable, water-containing gel-like cross-linked polymer (b), having solid content or centrifuge retention capacity different from solid content or centrifuge retention capacity of the cross-linked polymer (a) by equal to or larger than 1%, is subjected to coexistence.