Patent US4041228A successfully refreshed from Google Patents.
US4041228A
Expired / Lapsed
US
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Absorbent articles and methods for their preparation
Assignee: Dow Chemical Co
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Filing: 1975-05-09
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Granted: 1977-08-09
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Expires: 1995-05-09
Abstract
Abstract Water swellable absorbent articles, made from carboxylic polyelectrolytes, together with methods for their preparation, and a composition useful to make said articles are disclosed. The articles are crosslinked by heating and/or removing substantially all of the water from the precursor composition.
Inventors
- 👤 James Richard Gross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:43
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/02; D01F6/16; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
107 words
A method of preparing substantially water swellable polyelectrolyte fibers which comprises A. extruding a composition comprising 1. a solution of a carboxylic synthetic polyelectrolyte wherein the solution comprises water, lower alcohols, or mixtures thereof and about 5 to about 60% by weight of a carboxylic polyelectrolyte, and 2. at least about 0.1% by weight based on the polyelectrolyte of a crosslinking agent reactive with carboxylate groups into a bath comprising lower alkyl ketones or chlorinated hydrocarbons to form an extruded fiber, B. separating the extruded fiber from said bath, and C. heating said fibers to a temperature greater than about 30° C. to crosslink said polyelectrolyte fibers.
Claim 2
Independent Claim
107 words
A method of preparing substantially water swellable polyelectrolyte fibers which comprises A. extruding a composition comprising 1. a solution of a carboxylic synthetic polyelectrolyte wherein the solution comprises water, lower alcohols, or mixtures thereof and about 5 to about 60% by weight of a carboxylic polyelectrolyte, and 2. at least about 0.1% by weight based on the polyelectrolyte of a crosslinking agent reactive with carboxylate groups into a bath comprising lower alkyl ketones or chlorinated hydrocarbons to form an extruded fiber, B. separating the extruded fiber from said bath, and C. heating said fibers to a temperature greater than about 30° C. to crosslink said polyelectrolyte fibers.
Claim 3
Dependent Claim
23 words
A method as set forth in claim 1 wherein the crosslinking agent is present in the range from 0.1 - 10% by weight.
Claim 4
Dependent Claim
31 words
A method as set forth in claim 1 wherein the carboxylic polyelectrolyte consists of a terpolymer of ethyl acrylate, sodium acrylate, and sodium methacrylate with 50 mole percent being ethyl acrylate.
Claim 5
Dependent Claim
16 words
A method as set forth in claim 1 wherein the carboxylic polyelectrolyte consists of polysodium acrylate.
Claim 6
Dependent Claim
16 words
A method as set forth in claim 1 wherein the carboxylic polyelectrolyte consists of poly(isobutylenecodisodium maleate).
Claim 7
Dependent Claim
19 words
A method as set forth in claim 1 wherein the crosslinking agent is the diglycidyl ether of polypropylene glycol.
Claim 8
Dependent Claim
24 words
The method as set forth in claim 1 wherein said crosslinking agent is selected from polyhaloalkanols, sulfonium zwitterions, haloepoxyalkanes, polyglycidyl ethers, and mixtures thereof.
Claim 9
Dependent Claim
16 words
The method as set forth in claim 1 wherein the crosslinking agent is a polyglycidyl ether.
Claim 10
Dependent Claim
10 words
The polyelectrolyte fiber produced by the method of claim 1.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-08 | 1981-02-07 | 1981-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-08 | 1985-02-07 | 1985-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-08 | 1989-02-07 | 1989-08-09 | $7700.00 | Window Closed / Lapsed |