Nippon Shokubai Co., Ltd.

Shin-ichi Fujino

Kunihiko Ishizaki

Kazushi Torii

Kazuhiko Sakamoto

Satoshi Matsumoto

Yoshifumi Adachi

Taku Iwamura

Yoshihiro Shobo

Hiroyasu Watabe

Makiko Masuda

A method for producing a polyacrylic acid (salt)-based water absorbent resin, sequentially including the steps of: storing or producing acrylic acid; mixing acrylic acid containing a polymerization inhibitor with water, a crosslinking agent, and optionally, a basic composition, and/or neutralizing them, to prepare an aqueous monomer solution; polymerizing the aqueous monomer solution; drying an obtained water-containing gel-like crosslinked polymer; and optionally carrying out surface crosslinking, wherein the acrylic acid containing the polymerization inhibitor has a water content of not higher than 1,000 ppm (by mass; the same applies hereinafter), and/or the aqueous monomer solution has a formic acid content of 1 to 700 ppm, relative to the monomer.

Polyacrylic acid (salt)-based water absorbent resin and method for producing same

Growing community of inventors

Hyogo, Japan

Shin-ichi Fujino