发明名称 |
Method for producing polyacrylic acid (salt)-based water absorbent resin powder |
摘要 |
From a view point of reduction in an out of spec product after surface crosslinking, particularly, when an alkylene carbonate compound is used as a surface crosslinking agent, influence by an air temperature is great, and it is necessary to reduce ethylene glycol which is produced as a byproduct, and there is provided a process for producing a polyacrylic acid (salt)-based water absorbent resin powder, comprising
a step of polymerizing an aqueous acrylic acid (salt)-based monomer solution,a step of drying the resulting polymer,an optional grinding•classifying step, anda surface crosslinking step,wherein in the surface crosslinking step,(1) a surface crosslinking agent containing an alkylene carbonate compound and a polyhydric alcohol compound is mixed into a water absorbent resin powder, the mixture is heat-reacted and, further, simultaneously with, or separately from the mixing, an ion reactive surface crosslinking agent is mixed, and/or(2) mixing treatment of mixing a surface crosslinking agent solution into a water absorbent resin powder containing at least one or more kinds of ion reactive surface crosslinking agents is performed two or more times. |
申请公布号 |
US9567414(B2) |
申请公布日期 |
2017.02.14 |
申请号 |
US201213982166 |
申请日期 |
2012.01.30 |
申请人 |
Nippon Shokubai Co., Ltd. |
发明人 |
Nogi Kozo;Nakamura Masatoshi;Shibata Hirofumi;Honda Koji;Watanabe Yusuke;Matsumoto Satoshi;Nakatsuru Reiko;Ishizaki Kunihiko;Kimura Kazuki;Machida Sayaka |
分类号 |
C08F20/06;C08F220/06;C08J3/12;C09D133/04;C08J3/24 |
主分类号 |
C08F20/06 |
代理机构 |
Dickinson Wright PLLC |
代理人 |
Dickinson Wright PLLC |
主权项 |
1. A polyacrylic acid (salt)-based surface crosslinked water absorbent resin powder, wherein the polyacrylic acid (salt)-based surface crosslinked water absorbent resin powder has a saline flow conductivity (SFC) retention after a paint shaker test at 800 cycle/minute for 20 minutes of 80% or more, and comprises 100 to 1000 weight ppm of ethylene glycol, 1000 to 10000 weight ppm of a C3-C6 polyhydric alcohol, and a polyvalent metal cation or polyvalent cationic polymer, and an internal gas bubble ratio is 0.5% or more. |
地址 |
Osaka JP |