Patent US2278431A successfully refreshed from Google Patents.
US4517023A
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US
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Rust removal process using removable coatings of maleic acid copolymers
Assignee: GAF Chemicals Corp
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Filing: 1984-05-22
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Granted: 1985-05-14
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Expires: 2004-05-22
Abstract
Abstract Rust is removed from metal surfaces by applying a coating of an aqueous solution of a copolymer of maleic acid and monomer of the formula CH 2 ═CHR wherein R represents H, CH 3 , OR 1 or OCOR 1 and R 1 represents CH 3 or CH 2 CH 3 . The rust becomes incorporated into the coating during drying and the coating detaches itself from the metal surface for easy removal.
Inventors
- 👤 Eugene S. Barabas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:08
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/02; C23G1/025
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
89 words
Process for removing rust from a rusty metal surface which comprises: (a) applying to said rusty surface a layer of rust removal coating composition consisting essentially of an aqueous solution of a copolymer of maleic acid and monomer of the formula CH 2 ═CHR wherein R represents OR 1 and R 1 represents CH 3 or CH 2 CH 3 ; and (b) allowing said layer of coating composition to dry whereby rust becomes incorporated into said layer and the layer containing the rust detaches itself from the surface.
Claim 2
Dependent Claim
89 words
Process for removing rust from a rusty metal surface which comprises: (a) applying to said rusty surface a layer of rust removal coating composition consisting essentially of an aqueous solution of a copolymer of maleic acid and monomer of the formula CH 2 ═CHR wherein R represents OR 1 and R 1 represents CH 3 or CH 2 CH 3 ; and (b) allowing said layer of coating composition to dry whereby rust becomes incorporated into said layer and the layer containing the rust detaches itself from the surface.
Claim 3
Dependent Claim
19 words
Process according to claim 1 wherein the coating composition has a viscosity between about 50 and about 250,000 cps.
Claim 4
Dependent Claim
108 words
Process according to claim 1 wherein: (a) the coating composition consists essentially of between about 5 and about 60 wt % of said copolymer and between about 40 and about 95 wt % water; (b) the coating composition is applied to the rusty surface to form a layer between about 0.01 and about 20 mm thick; (c) the coating composition has a viscosity between about 50 and about 250,000 cps; and (d) the applied coating composition is allowed to dry for between about 0.5 and about 8 hours whereby the rust becomes incorporated into the layer of coating composition and the layer becomes detached from the metal surface.
Claim 5
Dependent Claim
19 words
Process according to claim 1 wherein R represents OR 1 and R 1 represents CH 2 CH 3 .
Claim 6
Dependent Claim
29 words
Process according to claim 1 wherein the coating composition contains between about 5 and about 60 wt % copolymer and between about 40 and about 95 wt % water.
Claim 7
Dependent Claim
26 words
Process according to claim 5 wherein the coating composition is applied to the rusty surface in a layer between about 0.01 and about 20 mm thick.
Claim 8
Dependent Claim
24 words
Process according to claim 6 wherein the layer of applied coating composition is allowed to dry for between about 0.5 and about 8 hours.
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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) | 1988-05-13 | 1988-11-12 | 1989-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-13 | 1992-11-12 | 1993-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-13 | 1996-11-12 | 1997-05-14 | $7700.00 | Window Closed / Lapsed |