Patent US3985671A successfully refreshed from Google Patents.
US3985671A
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US
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Scale control agents
Assignee: Universal Oil Products Co
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Filing: 1974-09-26
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Granted: 1976-10-12
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Expires: 1994-09-26
Abstract
Abstract A synergistic blend of a polyaminoalkylenephosphonate and a polyquaternary ammonium chloride compound is used as a scale control agent for recirculating water cooling equipment.
Inventors
- 👤 Herbert D. Clark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:40
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
36 words
The synergistic mixture of from about 90% to about 30% by weight of a polyaminoalkylenephosphonate in which the alkylene group is methylene, ethylene or propylene and from about 10% to about 70% by weight of poly[oxyethylene(dimethyliminio)ethylene(dimethyliminio)ethylenedichloride].
Claim 2
Dependent Claim
36 words
The synergistic mixture of from about 90% to about 30% by weight of a polyaminoalkylenephosphonate in which the alkylene group is methylene, ethylene or propylene and from about 10% to about 70% by weight of poly[oxyethylene(dimethyliminio)ethylene(dimethyliminio)ethylenedichloride].
Claim 3
Dependent Claim
15 words
The synergistic mixture as set forth in claim 1 in which said polyaminoalkylenephosphonate is polyaminomethylenephosphonate.
Claim 4
Dependent Claim
15 words
The synergistic mixture as set forth in claim 1 in which said polyaminoalkylenephosphonate is polyaminoethylenephosphonate.
Claim 5
Dependent Claim
15 words
The synergistic mixture as set forth in claim 1 in which said polyaminoalkylenephosphonate is polyaminopropylenephosphonate.
Claim 6
Dependent Claim
21 words
The method of controlling scale deposits in a water recirculating system which comprises adding thereto the synergistic mixture of claim 1.
Claim 7
Dependent Claim
32 words
The method as set forth in claim 5 in which said synergistic mixture is present in said system in an amount in the range of from about 1 to about 20 ppm.
References Cited (Backward Citations)
US3336221A
Cited
US3749759A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-12 | 1980-04-12 | 1980-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-12 | 1984-04-12 | 1984-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-12 | 1988-04-12 | 1988-10-12 | $7700.00 | Window Closed / Lapsed |