US3945843A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acrylic acid copolymer as pigment dispersant
Assignee: ChampionX LLC
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Filing: 1974-07-22
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Granted: 1976-03-23
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Expires: 1994-07-22
Abstract
Abstract An improved method for rapidly dispersing high solids suspensions, such as calcium carbonate slurries, using a copolymer of methyl acrylate and acrylic acid alone or along with sodium polyphosphates is disclosed.
Inventors
- 👤 David W. Holty
- 👤 George E. Lauterbach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:58
CPC Classifications
D; D21; D21H; D21H19/00; D21H19/36; D21H19/44; D21H19/56; D21H19/58; C; C09; C09D; C09D17/00; C09D17/004; D21H19/38; D21H19/385
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
56 words
An improved method for rapidly dispersing high solids suspensions having from 50-80% by weight of soilds which comprises adding from 0.2-1.4% by weight of a dispersant formed by the copolymerization of methyl acrylate and acrylic acid to said high solids suspensions wherein the weight ratio of methyl acrylate to acrylic acid is from 15:85 to 30:70.
Claim 2
Dependent Claim
56 words
An improved method for rapidly dispersing high solids suspensions having from 50-80% by weight of soilds which comprises adding from 0.2-1.4% by weight of a dispersant formed by the copolymerization of methyl acrylate and acrylic acid to said high solids suspensions wherein the weight ratio of methyl acrylate to acrylic acid is from 15:85 to 30:70.
Claim 3
Dependent Claim
18 words
The method of claim 1 in which the dispersant has a molecular weight of from 5,000 to 15,000.
Claim 4
Dependent Claim
19 words
The method of claim 1 in which the high solids suspensions is from 50 to 80% by weight solids.
Claim 5
Dependent Claim
18 words
The method of claim 1 in which the weight ratio of methyl acrylate to acrylic acid is 25:75.
Claim 6
Dependent Claim
17 words
The method of claim 1 in which the dispersant has been neutralized to a pH of 7.
Claim 7
Dependent Claim
17 words
The method of claim 1 in which the high solids suspensions is a paper coating pigment suspension.
Claim 8
Dependent Claim
17 words
The method of claim 6 in which the paper coating pigment suspension is a calcium carbonate suspension.
Claim 9
Dependent Claim
13 words
The method of claim 1 in which the dispersant also contains sodium polyphosphate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-23 | 1979-09-22 | 1980-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-23 | 1983-09-22 | 1984-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-23 | 1987-09-22 | 1988-03-23 | $7700.00 | Window Closed / Lapsed |