Water absorbing resin with improved internal structure and manufacturing method therefor
US8383746B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 2007 |
| Grant date | Feb 26, 2013 |
| Priority date | — |
| Expiry date | Aug 29, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2982
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
According to the present invention, the manufacturing method for the water absorbing resin involves the step of polymerizing a water-soluble unsaturated monomer, 0.06 of 5 mol % of which is composed of an internal crosslinking agent; and the step of drying a water-containing gel which has a thermally decomposing radical initiator content index of 40 to 100 at 100 to 250° C. The water absorbing resin of the present invention contains a water-soluble unsaturated monomer as a repeat unit for a major chain, 90 mol % of the monomer being composed of an acrylic acid and/or salt thereof, the resin having an internal crosslinking structure and exhibiting a weight-average molecular weight Mw of 360,000 to 1,000,000 daltons and an intrinsic viscosity IV of 2.1 to 6.0 dL/g where the weight-average molecular weight Mw and the intrinsic viscosity IV are measured after treatment under set 2 of hydrolysis conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.