Patent US4470897A successfully refreshed from Google Patents.
US4470897A
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Method of electroplating a corrosion-resistant zinc-containing deposit
Assignee: Bethlehem Steel Corp
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Filing: 1983-09-20
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Granted: 1984-09-11
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Expires: 2003-09-20
Abstract
Abstract This invention is directed to an electroplated product having improved resistance to corrosive attack, and to the method of making such product. More particularly, the invention hereof relates to a zinc or zinc-alloy electroplated product containing a homogeneous dispersion of corrosion inhibitive pigment produced by subjecting a ferrous substrate to an electroplating bath containing a corrosion inhibitive pigment, such as barium chromate.
Inventors
- 👤 Robert A. Iezzi
- 👤 Arif Humayun
- 👤 Stavros G. Fountoulakis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:28
CPC Classifications
C; C25; C25D; C25D15/00; C25D15/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
96 words
A method of producing a zinc-containing electroplated ferrous product having improved corrosion resistance, comprising the steps of: (a) selecting a ferrous substrate suitable for the reception of a zinc-containing electroplated coating; (b) preparing a zinc-containing electroplating chloride bath having a pH of at least 3.5; (c) adding to said bath barium chromate as a corrosion inhibitive pigment in the amount of at least 8 gm/l; and (d) passing said ferrous substrate through said bath while applying electric current to said bath whereby a coating containing particles of said barium chromate is applied to said ferrous substrate.
Claim 2
Independent Claim
96 words
A method of producing a zinc-containing electroplated ferrous product having improved corrosion resistance, comprising the steps of: (a) selecting a ferrous substrate suitable for the reception of a zinc-containing electroplated coating; (b) preparing a zinc-containing electroplating chloride bath having a pH of at least 3.5; (c) adding to said bath barium chromate as a corrosion inhibitive pigment in the amount of at least 8 gm/l; and (d) passing said ferrous substrate through said bath while applying electric current to said bath whereby a coating containing particles of said barium chromate is applied to said ferrous substrate.
Claim 3
Dependent Claim
16 words
The method according to claim 1 wherein said electroplating bath contains ZnCl 2 -BaCl 2 .
Claim 4
Dependent Claim
29 words
The method according to claim 2 wherein said pigment is a chromate and the concentration of Cr +6 in said electroplating bath is maintained at less than 0.3 g/l/.
Claim 5
Dependent Claim
18 words
The method according to claim 1 wherein said electroplating bath contains ZnCl 2 -BaCl 2 -NH 4Cl .
References Cited (Backward Citations)
US3061525A
Cited
US3268423A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-11 | 1988-03-12 | 1988-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-11 | 1992-03-12 | 1992-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-11 | 1996-03-12 | 1996-09-11 | $7700.00 | Window Closed / Lapsed |