Patent US3885914A successfully refreshed from Google Patents.
US3885914A
Expired / Lapsed
US
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Polymer-zinc corrosion inhibiting method
Assignee: Calgon Corp
•
Filing: 1973-06-04
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Granted: 1975-05-27
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Expires: 1993-06-04
Abstract
Abstract Use of low molecular weight polymers and zinc to inhibit the corrosion of metals by oxygen-bearing waters.
Inventors
- 👤 William Robert Hollingshad
- 👤 Paul Hotchkiss Ralston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:16
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
51 words
A METHOD OF INHIBITING THE CORROSION OF METALS IN A WATER SYSTEM COMPRISING MAINTAINING IN THE WATER OF SAID STSTEM AT LEAST ABOUT 5 PPM OF A COMPOSITION COMPRISING ZINC AND AT LEAST ONE LOW MOLECULAR WEIGHT POLYMER SELECTED FROM THE GROUP CONSISTING OF POLYACRYLAMIDE, POLY ACRYLIC ACID AND SODIUM POLACRYLATE.
Claim 2
Independent Claim
51 words
A METHOD OF INHIBITING THE CORROSION OF METALS IN A WATER SYSTEM COMPRISING MAINTAINING IN THE WATER OF SAID STSTEM AT LEAST ABOUT 5 PPM OF A COMPOSITION COMPRISING ZINC AND AT LEAST ONE LOW MOLECULAR WEIGHT POLYMER SELECTED FROM THE GROUP CONSISTING OF POLYACRYLAMIDE, POLY ACRYLIC ACID AND SODIUM POLACRYLATE.
Claim 3
Dependent Claim
20 words
A method as in claim 1 wherein the polymer has a molecular weight of from about 500 to about 10,000.
Claim 4
Dependent Claim
22 words
A method as in claim 1 wherein the ratio of polymer to zinc is from about 1:3 to about 5:1 by weight.
Claim 5
Dependent Claim
20 words
A method as in claim 1 wherein the ratio of polymer to zinc is from about 3:1 to about 4:1.
References Cited (Backward Citations)
US3723333A
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US3578589A
Cited
US3663448A
Cited
US3669615A
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US3709816A
Cited
US3709815A
Cited
US3816333A
Cited
US3669616A
Cited
US3752761A
Cited
US3766077A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |