Superabsorbent polymers
US5563218A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 1994 |
| Grant date | Oct 8, 1996 |
| Priority date | — |
| Expiry date | Aug 25, 2014 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61L15/24
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Superabsorbent, high gel strength/short gel time acrylic polymers, well suited for the production of items of feminine hygiene/adult incontinence, are prepared by (a) inversely suspending an aqueous acrylic monomer phase in an organic solvent in the presence of an emulsifying agent having an HLB of from 8 to 12, the aqueous monomer phase also comprising a crosslinking agent therefor, (b) polymerizing the inverse suspension of acrylic monomer into a polymer gel, (c) absorbing a second charge of acrylic monomer into the polymer gel thus attained, the ratio of the amount of the second monomer charge to the amount of monomer in the beginning aqueous phase ranging from 1 to 1.2, (d) introducing a surfactant having an HLB of from 2 to 5 into the medium of polymerization, and (e) polymerizing the second monomer charge within the polymer gel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.