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:
Nov. 17, 2020
Filed:
Feb. 08, 2017
Sumitomo Seika Chemicals Co., Ltd., Hyogo, JP;
Maoki Hama, Himeji, JP;
Koji Takagi, Himeji, JP;
Kenta Kumazawa, Himeji, JP;
Sho Isokawa, Himeji, JP;
Abstract
The present invention provides a method for producing water-absorbent resin particles that has a low stirring load, and can produce water-absorbent resin particles having a particle diameter within a specific range, with high productivity. The method for producing water-absorbent resin particles comprises adding an ethylenically unsaturated monomer all at once to a hydrocarbon dispersion medium mixed with a surfactant to perform reversed phase suspension polymerization, wherein the reversed phase suspension polymerization is performed in one step, or two or more steps, the surfactant is at least one selected from the group consisting of polyoxyethylene alkyl ether phosphates, alkali metal salts of polyoxyethylene alkyl ether phosphates, and alkaline earth metal salts of polyoxyethylene alkyl ether phosphates, and the surfactant has an HLB of 9 to 15.