US4495008A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of making long-life thin metal plate for automobile bodies, and thin plate made thereby
Assignee: SIDERTEK SPA A CORP ITALY
•
Filing: 1982-03-01
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Granted: 1985-01-22
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Expires: 2002-03-01
Abstract
Abstract Thin metal plate is cleaned and electrolytically pickled in an acid solution. A zinc layer is electrodeposited on one face of the plate, after which a chrome-chromic oxide coating is deposited on both faces of the plate from a sulphuric acid solution containing compounds of trivalent and exhavalent chrome. The plate is then subjected to a drying-oxidating treatment in air. The plate may be steel having a thickness between 0.1 and 2 mm. The plate may be surface treated by phosphating, and then painted. The chrome-chromic oxide coating may have a thickness between 0.05 and 5 μm, and the zinc coating a thickness between 1 and 30 μm.
Inventors
- 👤 Roberto Bruno
- 👤 Massimo Memmi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:25
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/05; C23C22/06; C23C22/24; C23C22/30; C25; C25D; C25D11/00; C25D11/38; C25D13/00; C25D13/20; C25D5/00; C25D5/34; C25D5/36; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12542; Y10T428/12549; Y10T428/12583; Y10T428/1259; Y10T428/12611; Y10T428/12618; Y10T428/12771; Y10T428/12785; Y10T428/12792; Y10T428/12799; Y10T428/12806; Y10T428/12826; Y10T428/12847; Y10T428/12854
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
43 words
A long-life sheet metal plate for automobile bodies, the sheet metal plate being coated on only one of its faces with a layer of zinc, and a chrome-chromic oxide coating covering both the zinc-coated face and the other face of the metal plate.
Claim 2
Dependent Claim
43 words
A long-life sheet metal plate for automobile bodies, the sheet metal plate being coated on only one of its faces with a layer of zinc, and a chrome-chromic oxide coating covering both the zinc-coated face and the other face of the metal plate.
Claim 3
Dependent Claim
22 words
A sheet metal plate as defined in claim 1 wherein the layer of zinc has a thickness between 1 and 30 μm.
Claim 4
Dependent Claim
22 words
A sheet metal plate as defined in claim 1 wherein the chrome-chromic oxide coating has a thickness between 0.05 and 5 μm.
Claim 5
Dependent Claim
26 words
A sheet metal plate as defined in claim 1 including a phosphate coating covering at least one chrome-chromic oxide coated face of the sheet metal plate.
Claim 6
Dependent Claim
23 words
A sheet metal plate as defined in claim 4 including a layer of paint covering a phosphate-coated face of the sheet metal plate.
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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) | 1988-01-22 | 1988-07-23 | 1989-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-22 | 1992-07-23 | 1993-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-22 | 1996-07-23 | 1997-01-22 | $7700.00 | Window Closed / Lapsed |