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. 23, 2006
Filed:
Dec. 17, 2002
Sei Nakahara, Himeji, JP;
Kunihiko Ishizaki, Suita, JP;
Hirotama Fujimaru, Himeji, JP;
Yasuhisa Nakashima, Himeji, JP;
Kazuhiko Sakamoto, Himeji, JP;
Sei Nakahara, Himeji, JP;
Kunihiko Ishizaki, Suita, JP;
Hirotama Fujimaru, Himeji, JP;
Yasuhisa Nakashima, Himeji, JP;
Kazuhiko Sakamoto, Himeji, JP;
Nippon Shokubai Co., Ltd., Osaka, JP;
Abstract
In order to produce inexpensively with high productivity a water-absorbent resin of which: the residual monomer content and the water-extractable content are both low, and the properties are high, and the colorability is low; there is provided a process for producing a water-absorbent resin, which is a process for producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane, with the process being characterized by comprising the steps of: preparing the monomer component from an acrylic acid composition that includes the unneutralized acrylic acid and a methoxyphenol and has a methoxyphenol content of 10 to 160 ppm by weight (based on the unneutralized acrylic acid); and then carrying out radical and/or ultraviolet polymerization of the resultant monomer component.