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. 07, 2013
Filed:
Sep. 11, 2009
Yorimichi Dairoku, Himeji, JP;
Kozo Nogi, Himeji, JP;
Syuji Kanzaki, Himeji, JP;
Kunihiko Ishizaki, Himeji, JP;
Koji Matsumoto, Himeji, JP;
Yoshiro Mitsukami, Himeji, JP;
Yorimichi Dairoku, Himeji, JP;
Kozo Nogi, Himeji, JP;
Syuji Kanzaki, Himeji, JP;
Kunihiko Ishizaki, Himeji, JP;
Koji Matsumoto, Himeji, JP;
Yoshiro Mitsukami, Himeji, JP;
Nippon Shokubai Co., Ltd., Osaka, JP;
Abstract
A method for the production of a water-absorbing resin is to be provided which permits enhancement and stabilization of property, for example, liquid permeability, of a water-absorbing resin by a simple and convenient method without requiring change of raw materials or expensive facility investment. The method comprises a polymerization step for polymerizing an aqueous solution of acrylic acid (or salt thereof) to obtain a hydrogel cross-linked polymer; a drying step for drying the hydrogel cross-linked polymer to obtain a water-absorbing resin powder; a classification step for classifying the water-absorbing resin powder; and a surface cross-linking step for surface cross-linking the water-absorbing resin powder before or after the classification step, wherein electricity is eliminated in the classification step.