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:
Jul. 29, 2014
Filed:
Jun. 08, 2011
Satoshi Matsumoto, Himeji, JP;
Syuji Kanzaki, Himeji, JP;
Kazumasa Konishi, Himeji, JP;
Nippon Shokubai Co., Ltd., Osaka, JP;
Abstract
A method for reducing colored foreign substances in a water absorbent resin by a convenient and simple technique in the production of a water absorbent resin, without requiring any modification of raw materials or high capital investment, is provided. The method for producing a particulate water absorbent resin includes a step of polymerizing an aqueous solution of an unsaturated monomer; and a step of drying a particulate water-containing gel-like cross-linked polymer having a solids concentration of 30% by weight or greater that is obtainable in a gel grain refining step during polymerization or after polymerization, with one or more apparatuses for aerating a water absorbent resin with a high temperature gas stream being installed in the drying step and/or in at least one of the subsequent steps, while in the aerating apparatus, the high temperature gas stream is passed through a filter and then is reused in the same step as the step where the aerating apparatus is installed, or in a different step.