Patent US4396734A successfully refreshed from Google Patents.
US4396734A
Expired / Lapsed
US
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Polymer stabilizers
Assignee: GAF Chemicals Corp
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Filing: 1981-03-20
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Granted: 1983-08-02
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Expires: 2001-03-20
Abstract
Abstract Polymer thickeners having a viscosity of at least 10 K, employed in acid media are stabilized with Redox indicators having from 6 to 30 carbon atoms, such as, for example, methylene blue, phenosafranine, pyronine Y, tartrazine, amaranth, methyl orange, an alkali metal salt of diphenylamine sulfonate and malachite green oxalate, which stabilizers are combined with the polymer in a concentration of between about 0.005 to about 1 weight %.
Inventors
- 👤 Earl P. Williams
- 👤 Donald H. Lorenz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:29
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/16; C08K5/0008; C08K5/005; Y; Y10; Y10S; Y10S507/00; Y10S507/907; Y10S507/933; Y10S507/934
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
80 words
A mucilage composition having a pH less than 7 containing between about 0.5 and about 25 weight % of a vinyl polymer thickener having a K value of between about 10 and about 250 and between about 0.005 and about 1 weight %, based on polymer, of a redox indicator having from 6 to 30 carbon atoms and containing at least one radical selected from the group consisting of amino, cyano and azo, to stabilize said polymer against acidic degradation.
Claim 2
Dependent Claim
80 words
A mucilage composition having a pH less than 7 containing between about 0.5 and about 25 weight % of a vinyl polymer thickener having a K value of between about 10 and about 250 and between about 0.005 and about 1 weight %, based on polymer, of a redox indicator having from 6 to 30 carbon atoms and containing at least one radical selected from the group consisting of amino, cyano and azo, to stabilize said polymer against acidic degradation.
Claim 3
Dependent Claim
35 words
A stabilized mucilage containing the composition of claim 1 and between about 5 and about 25 weight % acid to provide an acidic solution having a pH of from about 0.1 to less than 7.
Claim 4
Dependent Claim
25 words
The composition of claim 1 wherein the redox indicator is present in an amount between about 0.05 and about 0.75 weight %, based on polymer.
Claim 5
Dependent Claim
47 words
The composition of claim 1 wherein the stabilizer for polymers in acidic media is selected from the group consisting of methylene blue; methyl red, orange or green; pyronine Y; phenosafranine; tartrazine; amaranth; malachite green oxalate; basic blue; neutral red and an alkali metal salt of diphenylamine sulfonate.
Claim 6
Dependent Claim
10 words
The composition of claim 1 wherein said polymer is poly-N-vinyl-2-pyrrolidone.
Claim 7
Dependent Claim
18 words
The composition of claim 1 wherein said polymer is a copolymer of vinyl alkyl ether and maleic acid.
Claim 8
Dependent Claim
18 words
The composition of claim 1 wherein said polymer is a copolymer of vinyl alkyl ether and maleic anhydride.
Claim 9
Dependent Claim
19 words
The composition of claim 2 in which said polymer is an interpolymer of methyl vinyl ether and maleic anhydride.
Claim 10
Dependent Claim
16 words
The composition of claim 2 in which said polymer is poly-N-vinyl-2-pyrrolidone cross-linked with diallyl polyethylene glycol.
Claim 11
Dependent Claim
26 words
The composition of claim 2 in which said polymer is a polymer of alkyl vinyl ether wherein said alkyl contains from 1 to 2 carbon atoms.
Claim 12
Dependent Claim
12 words
The composition of claim 4 in which said indicator is methylene blue.
Claim 13
Dependent Claim
11 words
The composition of claim 4 in which said indicator is phenosafranine.
Claim 14
Dependent Claim
12 words
The composition of claim 4 in which said indicator is malachite green.
Claim 15
Dependent Claim
11 words
The composition of claim 4 in which said indicator is amaranth.
Claim 16
Dependent Claim
13 words
The composition of claim 4 in which said indicator is sodium diphenylamine sulfonate.
Claim 17
Dependent Claim
23 words
The composition of claim 4 in which said solution is an aqueous solution containing from 0.5 to 25 percent of a mineral acid.
Claim 18
Dependent Claim
12 words
The composition of claim 16 in which said acid is hydrogen chloride.
Claim 19
Dependent Claim
12 words
The composition of claim 16 in which said acid is phosphoric acid.
Claim 20
Dependent Claim
36 words
The composition of claim 2 comprising between about 0.5 and about 25% by weight of poly-N-vinyl-2-pyrrolidone in an acidic aqueous solution containing between about 0.05 and about 0.75 weight % based on polymer of methylene blue.
References Cited (Backward Citations)
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US4066595A
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US4197087A
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US4248636A
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US4225475A
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US4205998A
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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) | 1986-08-01 | 1987-01-31 | 1987-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-01 | 1991-01-31 | 1991-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-01 | 1995-01-31 | 1995-08-02 | $7700.00 | Window Closed / Lapsed |