Patent US4680124A successfully refreshed from Google Patents.
US4680124A
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US
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Polyacrylate scale inhibition
Assignee: ChampionX LLC
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Filing: 1987-01-08
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Granted: 1987-07-14
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Expires: 2007-01-08
Abstract
Abstract Small amounts of certain water-soluble phosphorous compounds prevent calcium polyacrylate scale.
Inventors
- 👤 Paul R. Young
- 👤 Mary E. Koutek
- 👤 John A. Kelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:27
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14; C02F5/086
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
69 words
The invention comprises a method of preventing the formation of calcium polyacrylate scale on industrial heat transfer surfaces which are in contact with water which contains a scale-forming species of calcium polyacrylate which comprises treating the water with a phosphorous compound from the group consisting of compounds capable of producing phosphate ions and water-soluble phosphonates with the amount of phosphorous compound being less than the amount of calcium polyacrylate.
Claim 2
Dependent Claim
69 words
The invention comprises a method of preventing the formation of calcium polyacrylate scale on industrial heat transfer surfaces which are in contact with water which contains a scale-forming species of calcium polyacrylate which comprises treating the water with a phosphorous compound from the group consisting of compounds capable of producing phosphate ions and water-soluble phosphonates with the amount of phosphorous compound being less than the amount of calcium polyacrylate.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the compound capable of producing phosphate ion is an alkali metal polyphosphate.
Claim 4
Dependent Claim
13 words
The method of claim 2 wherein the polyphosphate is an alkali metal tripolyphosphate.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein the compound capable of producing phosphate ion is an orthophosphate.
Claim 6
Dependent Claim
11 words
The method of claim 4 wherein the orthophosate is trisodium phosphate.
Claim 7
Dependent Claim
21 words
The method of claim 1 wherein the phosphonate is from the grouop consisting of 1-hydroxyl, ethylidene diphosphonic acid and 2-phosphonobutane-1,2,4-tricarboxylic acid.
References Cited (Backward Citations)
US3890228A
Cited
US4457847A
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US4457847B1
Cited
US4457847B2
Cited
US4502978A
Cited
US4576722A
Cited
US4634532A
Cited
US4566973A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-13 | 1991-01-12 | 1991-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-13 | 1995-01-12 | 1995-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-13 | 1999-01-12 | 1999-07-14 | $7700.00 | Window Closed / Lapsed |