Patent US3810183A successfully refreshed from Google Patents.
US3772142A
Expired / Lapsed
US
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N-sulfohydrocarbon-substituted acrylamide polymers as formation aids for non-woven stock
Assignee: Lubrizol Corp
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Filing: 1971-03-23
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Granted: 1973-11-13
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Expires: 1991-03-23
Abstract
Abstract Polymers of N-sulfohydrocarbon-substituted acrylamides, especially the alkali metal salts of 2-acrylamido-2methylpropanesulfonic acid, are useful as fiber dispersants in the preparation of paper and similar stock.
Inventors
- 👤 R Doggett
- 👤 R Tschirch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:05
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/41; D21H17/42; C; C08; C08F; C08F28/00; D21F; D21F11/00; D21F11/004; D21H13/00; D21H13/10; D21H5/00; D21H5/12; D21H5/1254; Y; Y10; Y10S; Y10S516/00; Y10S516/01; Y10S516/03; Y10S516/05
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
18 words
A slurry according to claim 1 wherein the fibers are adapted for the formation of non-woven stock therefrom.
Claim 2
Dependent Claim
12 words
A slurry according to claim 2 wherein R1 is hydrogen or methyl.
Claim 3
Dependent Claim
25 words
A slurry according to claim 3 wherein the water-soluble polymer is a homopolymer of an alkali metal 2-acrylamido-2-methylpropanesulfonate, or a copolymer thereof with acrylic acid.
Claim 4
Dependent Claim
13 words
A slurry according to claim 4 wherein the water-soluble polymer is a homopolymer.
Claim 5
Dependent Claim
65 words
In a method for producing non-woven stock which comprises forming a sheet from an aqueous slurry of a plurality of fibers, the improvement which comprises adding to said slurry, as a dispersant for said fibers, about 0.1-10 percent by weight, based on the weight of said fibers, of at least one water-soluble polymer containing at least five percent by weight of units of the formula
Claim 6
Dependent Claim
12 words
A method according to claim 6 wherein R1 is hydrogen or methyl.
Claim 7
Dependent Claim
25 words
A method according to claim 7 wherein the water-soluble polymer is a homopolymer of an alkali metal 2-acrylamido-2-methylpropanesulfonAte, or a copolymer thereof with acrylic acid.
Claim 8
Dependent Claim
13 words
A method according to claim 8 wherein the water-soluble polymer is a homopolymer.
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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) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |