US3966679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Absorbent articles and methods for their preparation
Assignee: Dow Chemical Co
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Filing: 1975-05-09
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Granted: 1976-06-29
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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. The absorbent articles are useful as surgical sponges, diapers, tampons, meat trays, bath mats and the like.
Inventors
- 👤 James R. Gross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:25
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/02; D01F6/16; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; Y; Y10; Y10S; Y10S521/00; Y10S521/905
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
60 words
A method of preparing a substantially dry water swellable particulate polyelectrolyte which comprises the steps of A. applying a coating on an impervious substrate wherein the coating comprises 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.
Claim 2
Independent Claim
60 words
A method of preparing a substantially dry water swellable particulate polyelectrolyte which comprises the steps of A. applying a coating on an impervious substrate wherein the coating comprises 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.
Claim 3
Dependent Claim
48 words
at least about 0.1% by weight based on the polyelectrolyte of a crosslinking agent reactive with carboxylate groups, B. heating said coated substrate to a temperature greater than about 30°C. to crosslink said polyelectrolyte to form a film, C. separating said crosslinked polyelectrolyte film from said substrate, and
Claim 4
Dependent Claim
48 words
at least about 0.1% by weight based on the polyelectrolyte of a crosslinking agent reactive with carboxylate groups, B. heating said coated substrate to a temperature greater than about 30°C. to crosslink said polyelectrolyte to form a film, C. separating said crosslinked polyelectrolyte film from said substrate, and
Claim 5
Dependent Claim
40 words
D. disintegrating said film to form flakes, strips, or powders thereof. 2. The method as set forth in claim 1 wherein the crosslinking agent reactive with carboxylate groups is selected from polyhaloalkanoles, sulfonium zwitterions, haloepoxyalkanes, polyglycidyl ethers, and mixtures thereof.
Claim 6
Dependent Claim
16 words
The method as set forth in claim 2 wherein the crosslinking agent is a polyglycidyl ether.
Claim 7
Dependent Claim
18 words
The method as set forth in claim 3 wherein the crosslinking agent is an alkylene glycol diglycidyl ether.
Claim 8
Dependent Claim
15 words
The method as set forth in claim 3 wherein the crosslinking agent is glycerine-1,3-diglycidyl ether.
Claim 9
Dependent Claim
30 words
The method as set forth in claim 3 wherein the crosslinking agent is a polypropylene glycol diglycidyl ether having an epoxy equivalent weight range from about 175 to about 380.
Claim 10
Dependent Claim
30 words
The method as set forth in claim 3 wherein the crosslinking agent is a bisphenol A-epichlorohydrin epoxy resin having an epoxy equivalent weight range from about 182 to about 975.
Claim 11
Dependent Claim
19 words
The water swellable particulate polyelectrolyte, in the form of flakes or strips, produced by the method of claim 1.
Claim 12
Dependent Claim
18 words
The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 2.
Claim 13
Dependent Claim
18 words
The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 3.
Claim 14
Dependent Claim
18 words
The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 4.
Claim 15
Dependent Claim
18 words
The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 5.
Claim 16
Dependent Claim
18 words
The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 6.
Claim 17
Dependent Claim
18 words
The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 7.
References Cited (Backward Citations)
US3669103A
Cited
US3810468A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |