US4840820A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroless nickel plating of aluminum
Assignee: MacDermid Enthone Inc
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Filing: 1985-10-15
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Granted: 1989-06-20
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Expires: 2005-10-15
Abstract
Abstract A process is provided for improving the electroless nickel plating of aluminum which has been pretreated with a barrier coating such as zinc by employing multiple plating baths under controlled operating conditions.
Inventors
- 👤 Paul B. Schultz
- 👤 Eugene F. Yarkosky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:10
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/16; C23C18/1601; C23C18/1633; C23C18/1646; C23C18/165; C23C18/1651; C23C18/1675; C23C18/1683; C23C18/31; C23C18/32; C23C18/34; C23C18/36; C23C18/38
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
127 words
In a process for plating zinc or tin coated aluminum substrates with an adherent, non-blistered electroless metal coating by metal plating from a first electroless plating bath to the desired thickness, the bath being replenished as needed to maintain the desired metal concentration, and with the bath being used until the electroless metal coatings produced on the substrates are non-adherent and blistered after which the bath is discarded, the improvement whereby the lift of the bath is increased comprising: plating a thin coating of the metal on the substrates from a second electroless metal plating bath prior to plating to the desired thickness with the first bath, both electroless metal plating baths containing a source of metal ions and a reducing agent to reduce the metal ions.
Claim 2
Dependent Claim
127 words
In a process for plating zinc or tin coated aluminum substrates with an adherent, non-blistered electroless metal coating by metal plating from a first electroless plating bath to the desired thickness, the bath being replenished as needed to maintain the desired metal concentration, and with the bath being used until the electroless metal coatings produced on the substrates are non-adherent and blistered after which the bath is discarded, the improvement whereby the lift of the bath is increased comprising: plating a thin coating of the metal on the substrates from a second electroless metal plating bath prior to plating to the desired thickness with the first bath, both electroless metal plating baths containing a source of metal ions and a reducing agent to reduce the metal ions.
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein the thin metal coating on the zinc coating is up to about 0.1 mil.
Claim 4
Dependent Claim
20 words
The process of claim 2 wherein the thin metal coating on the zinc coating is about 0.005 to 0.08 mils.
Claim 5
Dependent Claim
16 words
The process of claim 1 wherein the metal baths are cobalt, copper, nickel or alloys thereof.
Claim 6
Dependent Claim
10 words
The process of claim 4 wherein the metal is nickel.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-19 | 1992-12-19 | 1993-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-19 | 1996-12-19 | 1997-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-19 | 2000-12-19 | 2001-06-20 | $7700.00 | Window Closed / Lapsed |