US4806578A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing highly absorptive resin
Assignee: Kao Corp
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Filing: 1986-08-15
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Granted: 1989-02-21
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Expires: 2006-08-15
Abstract
Abstract A highly absorptive resin is produced by crosslinking a starting polymer being hydrophilic, having a carboxylic group or a carboxylate group, having a water content of 10 to 40 percent by weight, with a polyglycidyl ether having 4 or more epoxy groups, being water-soluble. The resin has a long life in absorption.
Inventors
- 👤 Takatoshi Kobayashi
- 👤 Takahiro Ohya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 09:57
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/20; C08G59/32; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; C08L; C08L63/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
53 words
A process for producing a highly absorptive resin, which comprises the step of crosslinking a hydrous hydrophilic starting polymer, having a carboxylic acid group or a carboxylate group thereof, and having a water content of 10 to 40 percent by weight, with a water soluble polyglycidyl ether having at least 4 expoxy groups.
Claim 2
Dependent Claim
53 words
A process for producing a highly absorptive resin, which comprises the step of crosslinking a hydrous hydrophilic starting polymer, having a carboxylic acid group or a carboxylate group thereof, and having a water content of 10 to 40 percent by weight, with a water soluble polyglycidyl ether having at least 4 expoxy groups.
Claim 3
Dependent Claim
22 words
A process as claimed in claim 1, which comprises the step of adjusting said water content of the starting polymer by dehydration.
Claim 4
Dependent Claim
31 words
A process as claimed in claim 1, in which said polyglycidyl ether is used in an amount of 0.01 to 5 percent by weight per weight of said hydrophilic starting polymer.
Claim 5
Dependent Claim
39 words
A process as claimed in claim 1, which further comprises the step of obtaining the starting polymer by polymerizing a hydrophilic monomer having a carboxylic group or a carboxylate group with a water-soluble initiator by reversed phase suspension polymerization.
Claim 6
Dependent Claim
25 words
A process as claimed in claim 1, in which said starting polymer is a polymer or copolymer of acrylic acid or an alkali metal acrylate.
Claim 7
Dependent Claim
13 words
A highly absorptive resin obtained by the process as claimed in claim 1.
Claim 8
Dependent Claim
28 words
A process as claimed in claim 1, wherein said polyglycidyl ether is selected from the group consisting of sorbitol polyglycidyl ether, pentaerythritol polyglycidyl ether and polyglycerol polyglycidyl ether.
References Cited (Backward Citations)
US4666983A
Cited
US4666975A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-02-21 | 1992-08-22 | 1993-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-21 | 1996-08-22 | 1997-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-21 | 2000-08-22 | 2001-02-21 | $7700.00 | Window Closed / Lapsed |