US4326888A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-rust composition
Assignee: Genentech Inc
•
Filing: 1979-10-01
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Granted: 1982-04-27
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Expires: 1999-10-01
Abstract
Abstract An anti-rust composition comprising citric acid, a metal chloride and film forming material which when applied to a rusty substrate will convert the rust into a harmless reaction product and provide a coating for receiving a finish paint.
Inventors
- 👤 Jeremy G. M. Frew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:34
CPC Classifications
C; C09; C09D; C09D5/00; C09D5/08; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31678; Y10T428/31692
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
167 words
A composition for application to the rusted surface of a ferrous metal article to inactivate the rust thereon and prevent further rusting, which consists essentially of an aqueous dispersion or emulsion of a water-insoluble film-forming material forming after drying a tough durable adherent coating upon said surface, and dissolved in the aqueous phase of said emulsion citric acid and a water-soluble metal chloride in sufficient proportions to react in situ with the rust to form a reaction product therewith to inactivate the same and prevent further rusting, the reaction product of said citric acid and said chloride with the rust remaining within said coating of said film-forming material, the amount of said film-forming material being in the range of about 50-75%, the amount of said citric acid being in the range of about 20-30%, and the amount of said chloride being in the range of about 10-20%, all percentages being by weight on a dry basis of the mixture of said film-forming material, citric acid, and chloride.
Claim 2
Dependent Claim
167 words
A composition for application to the rusted surface of a ferrous metal article to inactivate the rust thereon and prevent further rusting, which consists essentially of an aqueous dispersion or emulsion of a water-insoluble film-forming material forming after drying a tough durable adherent coating upon said surface, and dissolved in the aqueous phase of said emulsion citric acid and a water-soluble metal chloride in sufficient proportions to react in situ with the rust to form a reaction product therewith to inactivate the same and prevent further rusting, the reaction product of said citric acid and said chloride with the rust remaining within said coating of said film-forming material, the amount of said film-forming material being in the range of about 50-75%, the amount of said citric acid being in the range of about 20-30%, and the amount of said chloride being in the range of about 10-20%, all percentages being by weight on a dry basis of the mixture of said film-forming material, citric acid, and chloride.
Claim 3
Dependent Claim
14 words
An anti-rust composition according to claim 1, wherein the metal chloride is zinc chloride.
Claim 4
Dependent Claim
15 words
An anti-rust composition according to claim 1, wherein the film-forming material is an acrylic polymer.
Claim 5
Dependent Claim
16 words
An anti-rust composition according to claim 3, wherein the film-forming material is a styrene-modified acrylic resin.
Claim 6
Dependent Claim
23 words
A method of inactivating and preventing further rusting of a rusted iron substrate, comprising applying to the substrate the composition of claim 1.
Claim 7
Dependent Claim
25 words
An iron metal surface containing rust and having thereon a tough durable adherent coating obtained by applying the composition of claim 1 to said surface.
Claim 8
Dependent Claim
15 words
The iron metal surface of claim 6 wherein said film-forming material is an acrylic polymer.
References Cited (Backward Citations)
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US3729423A
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US3839255A
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US4086182A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-04-26 | 1985-10-26 | 1986-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-04-26 | 1989-10-26 | 1990-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-04-26 | 1993-10-26 | 1994-04-27 | $7700.00 | Window Closed / Lapsed |