US5439993A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of highly water absorptive polymers
Assignee: Mitsubishi Chemical Corp
•
Filing: 1994-03-31
•
Granted: 1995-08-08
•
Expires: 2014-03-31
Abstract
Abstract A process for producing a highly water absorptive polymer, including the step of polymerizing an acrylic monomer including as the main component acrylic acid and/or an alkali metal salt thereof in the presence of a salt of a metal selected from the,group consisting of Fe(II), Fe(III), Cu(II), Mn(II), VO(II), Co(II) and Ni(II).
Inventors
- 👤 Kiichi Ito
- 👤 Shinji Tsunoi
- 👤 Tetsuya Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:17
CPC Classifications
C; C08; C08F; C08F20/00; C08F20/02; C08F20/04; C08F20/06; C08F8/00; C08F8/42
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
82 words
A process for producing a water-insoluble highly water absorptive polymer, comprising the step of: polymerizing an acrylic monomer comprising as the main component acrylic acid and/or an alkali metal salt thereof, and a crosslinking monomer, in the presence of a salt of a metal selected from the group consisting of Fe(II) , Fe(III) , Cu(II) , Mn(II) , VO(II), Co(II) and Ni(II), wherein the amount of said salt of a metal is 0.001 to 1% by weight based on the acrylic monomer.
Claim 2
Dependent Claim
82 words
A process for producing a water-insoluble highly water absorptive polymer, comprising the step of: polymerizing an acrylic monomer comprising as the main component acrylic acid and/or an alkali metal salt thereof, and a crosslinking monomer, in the presence of a salt of a metal selected from the group consisting of Fe(II) , Fe(III) , Cu(II) , Mn(II) , VO(II), Co(II) and Ni(II), wherein the amount of said salt of a metal is 0.001 to 1% by weight based on the acrylic monomer.
Claim 3
Dependent Claim
26 words
The process according to claim 1, wherein the crosslinking monomer is selected from the group consisting of N,N'-methylenebisacrylamide, N,N'-methylenebismethacrylamide, ethylene glycol di(meth)acrylate and polyethylene glycol di(meth)acrylate.
Claim 4
Dependent Claim
15 words
The process according to claim 1, wherein said salt of a metal is an oxychloride.
Claim 5
Dependent Claim
23 words
The process according to claim 1, wherein the salt of the metal is an iron(III) salt, a copper(II) salt or a vanadyl(I) salt.
References Cited (Backward Citations)
US2683140A
Cited
US2789099A
Cited
US4090013A
Cited
US4145495A
Cited
US4314044A
Cited
EP0183466B1
Cited
US4659793A
Cited
US5086133A
Cited
JPH0331306A
Cited
US5100980A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-07 | 1999-02-06 | 1999-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-07 | 2003-02-06 | 2003-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-07 | 2007-02-06 | 2007-08-08 | $7700.00 | Window Closed / Lapsed |