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US4120655A
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Method for the inhibition of corrosion of ferrous metals in an aqueous medium
Assignee: Societe National Elf Aquitaine
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Filing: 1977-07-11
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Granted: 1978-10-17
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Expires: 1997-07-11
Abstract
Abstract The method for the inhibition of corrosion of ferrous metals in an aqueous medium consists in adding to the aqueous medium 10 to 2000 ppm of a mixture constituted by a water-soluble complex salt of a metal of groups II to VIII of the periodic table and of a hydroxycarboxylic acid and by a phosphoric ester of alkanolamine.
Inventors
- 👤 Michel Crambes
- 👤 Henri Grangette
- 👤 Pierre Pivette
- 👤 Philippe Haicour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:33
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
75 words
A method for the inhibition of corrosion of ferrous metals in an aqueous medium consisting of adding to the aqueous medium from about 10 to 2000 ppm of a mixture consisting essentially of a water-soluble complex salt of a metal of groups II to VIII of the periodic table and of a hydrocarboxylic acid selected from the group consisting of tartaric, citric, maleic, gluconic and salicylic acids together with a phosphoric ester of an alkanolamine.
Claim 2
Independent Claim
75 words
A method for the inhibition of corrosion of ferrous metals in an aqueous medium consisting of adding to the aqueous medium from about 10 to 2000 ppm of a mixture consisting essentially of a water-soluble complex salt of a metal of groups II to VIII of the periodic table and of a hydrocarboxylic acid selected from the group consisting of tartaric, citric, maleic, gluconic and salicylic acids together with a phosphoric ester of an alkanolamine.
Claim 3
Dependent Claim
18 words
A method according to claim 1, wherein the phosphoric ester of alkanolamine is a phosphoric ester of diethanolamine.
Claim 4
Dependent Claim
17 words
A method according to claim 1, wherein the mixture is employed in the form of a solution.
Claim 5
Dependent Claim
15 words
A method according to claim 1, wherein the aqueous medium has a high salt content.
Claim 6
Dependent Claim
30 words
A method according to claim 1, wherein the metal employed for salifying the hydroxycarboxylic acid is selected from the group consisting of zinc, iron, nickel, manganese, cobalt, cadmium and lead.
Claim 7
Dependent Claim
12 words
A method according to claim 5, wherein the salifying metal is zinc.
References Cited (Backward Citations)
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US3699052A
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US3714066A
Cited
US3718603A
Cited
US3723347A
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US3873465A
Cited
US3868217A
Cited
US4066398A
Cited
US3932303A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-16 | 1982-04-17 | 1982-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-16 | 1986-04-17 | 1986-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-16 | 1990-04-17 | 1990-10-17 | $7700.00 | Window Closed / Lapsed |