Polyacrylic acid (salt) water-absorbing resin and manufacturing method therefor
US9320822B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 2013 |
| Grant date | Apr 26, 2016 |
| Priority date | — |
| Expiry date | Feb 18, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2333/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention provides a method for manufacturing a water-absorbing resin which (i) is made of acrylic acid that is suitable for mass production of water-absorbing resin and (ii) has an excellent water-absorbing property. In the method, a polyacrylic acid (salt)-based water-absorbing resin is manufactured by sequentially carrying out predetermined monomer preparing step, polymerization step, drying step, and surface crosslinking step. An acetic acid concentration in acrylic acid or the like supplied in the monomer preparing step is in a range of 300 ppm to 10000 ppm on the acrylic acid basis, and an acetic acid concentration lowering rate defined by a predetermined formula is 35% or higher.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.