US4500670A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite mixtures for improving gel strength of water absorbent gels
Assignee: Dow Chemical Co
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Filing: 1983-11-22
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Granted: 1985-02-19
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Expires: 2003-11-22
Abstract
Abstract Water absorbent compositions exhibiting increased gel strengths comprise a water-swellable hydrophilic polymer and an inorganic powder and are prepared by physically blending the polymer and powder. The compositions can be incorporated into film laminates and can be employed in preparing improved disposable diapers.
Inventors
- 👤 Mark J. McKinley
- 👤 Dan P. Sheridan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:26
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/34; C08K3/346; A; A61; A61L; A61L15/00; A61L15/16; A61L15/18; A61L15/42; A61L15/60; C08J; C08J3/00; C08J3/20; C08J3/203; C08J2300/00; C08J2300/14; Y; Y10; Y10S; Y10S524/00; Y10S524/904; Y10S524/916
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
68 words
An improved water absorbent composition comprising (1) a water absorbing amount of a lightly crosslinked, water-swellable hydrophilic polymer and (2) an inorganic powder in an amount sufficient to increase gel strength exhibited by said water absorbent composition, wherein said composition is prepared by physically blending said inorganic powder with said polymer and wherein said powder is blended with said polymer after the polymer has been polymerized and crosslinked.
Claim 2
Dependent Claim
68 words
An improved water absorbent composition comprising (1) a water absorbing amount of a lightly crosslinked, water-swellable hydrophilic polymer and (2) an inorganic powder in an amount sufficient to increase gel strength exhibited by said water absorbent composition, wherein said composition is prepared by physically blending said inorganic powder with said polymer and wherein said powder is blended with said polymer after the polymer has been polymerized and crosslinked.
Claim 3
Independent Claim
76 words
A method for increasing the gel strength of a water absorbent composition comprising a water absorbent amount of a crosslinked water-swellable hydrophilic polymer wherein an inorganic powder is blended with said polymer in an amount sufficient to increase the gel strength of said water absorbent composition, said method comprising the physical blending of said inorganic powder with said polymer, and wherein said powder is blended with said polymer after the polymer has been polymerized and crosslinked.
Claim 4
Independent Claim
76 words
A method for increasing the gel strength of a water absorbent composition comprising a water absorbent amount of a crosslinked water-swellable hydrophilic polymer wherein an inorganic powder is blended with said polymer in an amount sufficient to increase the gel strength of said water absorbent composition, said method comprising the physical blending of said inorganic powder with said polymer, and wherein said powder is blended with said polymer after the polymer has been polymerized and crosslinked.
Claim 5
Dependent Claim
12 words
A composition of claim 1 wherein said inorganic powder is a clay.
Claim 6
Dependent Claim
12 words
A method of claim 2 wherein said inorganic powder is a clay.
Claim 7
Dependent Claim
47 words
A composition of claim 1 wherein the amount of said polymer ranges from about 1 to about 99 weight percent, and the amount of said inorganic powder ranges from about 1 to about 99 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 8
Dependent Claim
47 words
A method of claim 2 wherein the amount of said polymer ranges from about 1 to about 99 weight percent, and the amount of said inorganic powder ranges from about 1 to about 99 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 9
Dependent Claim
47 words
A composition of claim 1 wherein the amount of said polymer ranges from about 20 to about 90 weight percent, and the amount of said inorganic powder ranges from about 10 to about 80 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 10
Dependent Claim
47 words
A method of claim 2 wherein the amount of said polymer ranges from about 20 to about 90 weight percent, and the amount of said inorganic powder ranges from about 10 to about 80 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 11
Dependent Claim
47 words
A composition of claim 1 wherein the amount of said polymer ranges from about 40 to about 75 weight percent, and the amount of said inorganic powder ranges from about 25 to about 60 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 12
Dependent Claim
47 words
A method of claim 2 wherein the amount of said polymer ranges from about 40 to about 75 weight percent, and the amount of said inorganic powder ranges from about 25 to about 60 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 13
Dependent Claim
47 words
A composition of claim 1 wherein the amount of said polymer ranges from about 50 to about 60 weight percent, and the amount of said inorganic powder ranges from about 40 to about 50 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 14
Dependent Claim
47 words
A method of claim 2 wherein the amount of said polymer ranges from about 50 to about 60 weight percent, and the amount of said inorganic powder ranges from about 40 to about 50 weight percent, based on the total weight of the polymer and inorganic powder.
Claim 15
Dependent Claim
17 words
A composition of claim 1 wherein essentially dry polymer is physically blended with essentially dry inorganic powder.
Claim 16
Dependent Claim
17 words
A method of claim 2 wherein essentially dry polymer is physically blended with essentially dry inorganic powder.
Claim 17
Dependent Claim
13 words
A composition of claim 3 wherein said clay is sodium bentonite or attapulgite.
Claim 18
Dependent Claim
13 words
A method of claim 4 wherein said clay is sodium bentonite or attapulgite.
Claim 19
Dependent Claim
20 words
A composition of claim 1 wherein said powder is a grouping or aggregate of solid particles smaller than 1000 μm.
Claim 20
Dependent Claim
20 words
A method of claim 2 wherein said powder is a grouping or aggregate of solid particles smaller than 1000 μm.
Claim 21
Dependent Claim
18 words
A composition of claim 1 wherein said water-swellable hydrophilic polymer contains polymerized monomers of N-sulfoalkyl, α,β-ethylenically unsaturated salts.
Claim 22
Dependent Claim
18 words
A method of claim 2 wherein said water-swellable hydrophilic polymer contains polymerized monomers of N-sulfoalkyl, α,β-ethylenically unsaturated salts.
Claim 23
Dependent Claim
12 words
A composition of claim 1 wherein said powder is a synthetic silicate.
Claim 24
Dependent Claim
12 words
A method of claim 2 wherein said powder is a synthetic silicate.
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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) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |