Patent US4057511A successfully refreshed from Google Patents.
US4057511A
Expired / Lapsed
US
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Process for preventing corrosion and the formation of scale in water circulating system
Assignee: Bayer AG
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Filing: 1975-11-06
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Granted: 1977-11-08
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Expires: 1995-11-06
Abstract
Abstract Preventing corrosion and scale formation in water re-circulating systems by adding to the water to be circulated from about 5 to 100 g/m 3 , based on the weight of the water to be circulated, of a compound selected from the group consisting of those of the formula ##STR1## and the water-soluble salts thereof and then circulating said water in said system, R being hydrogen, alkyl, alkenyl or alkinyl having up to 4 carbon atoms; phenyl; cycloalkyl having 3 to 6 carbon atoms; benzyl; phenethyl or ##STR2## wherein R' is hydrogen, alkyl having 1 to 4 carbon atoms or carboxyl, R" is hydrogen or methyl and R'" is carboxyl.
Inventors
- 👤 Gerhard Bohnsack
- 👤 Hans Geffers
- 👤 Herbert Kallfass
- 👤 Walter Radt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:45
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14; C02F5/145; C23; C23F; C23F11/00; C23F11/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
99 words
A composition for preventing corrosion and the formation of scale in water-conducting systems which comprises by weight 1 to 20% of a Zn salt, 5 to 30% by weight of H 3 PO 4 , and the balance of a compound of the formula ##STR5## wherein R is hydrogen, alkyl, alkenyl, or alkinyl having up to 4 carbon atoms; phenyl; cycloalkyl having 3 to 6 carbon atoms; benzyl; phenethyl or ##STR6## wherein R' is hydrogen, alkyl having 1 to 4 carbon atoms or carboxyl, R'' is hydrogen or methyl and R''' is carboxyl or a water soluble salt thereof.
Claim 2
Dependent Claim
99 words
A composition for preventing corrosion and the formation of scale in water-conducting systems which comprises by weight 1 to 20% of a Zn salt, 5 to 30% by weight of H 3 PO 4 , and the balance of a compound of the formula ##STR5## wherein R is hydrogen, alkyl, alkenyl, or alkinyl having up to 4 carbon atoms; phenyl; cycloalkyl having 3 to 6 carbon atoms; benzyl; phenethyl or ##STR6## wherein R' is hydrogen, alkyl having 1 to 4 carbon atoms or carboxyl, R'' is hydrogen or methyl and R''' is carboxyl or a water soluble salt thereof.
Claim 3
Dependent Claim
15 words
The composition of claim 1 wherein the compound of said formula is zinc 2-phosphono-butane-tricarboxlic acid-(1,2,4).
Claim 4
Dependent Claim
22 words
The composition of claim 1 wherein the compound of said formula is 2-phosphono-butane-tricarboxylic acid-(1,2,4) or a water soluble base addition salt thereof.
References Cited (Backward Citations)
US3483133A
Cited
US3738806A
Cited
US3532639A
Cited
US3510436A
Cited
GB1282078A
Cited
US3714066A
Cited
US3723347A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-11-07 | 1981-05-09 | 1981-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-07 | 1985-05-09 | 1985-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-07 | 1989-05-09 | 1989-11-08 | $7700.00 | Window Closed / Lapsed |