US3971861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alloy plating system
Assignee: Handy Chemicals Ltd
•
Filing: 1974-10-25
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Granted: 1976-07-27
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Expires: 1994-10-25
Abstract
Abstract Electroless deposition of tin-nickel alloys is carried out using a plating solution containing a tin salt, a nickel salt and thiourea. The solution is particularly useful for spray or immersion plating of bronze Fourdrinier screens.
Inventors
- 👤 Lionel de Waltoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:03
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/16; C23C18/48; Y; Y10; Y10S; Y10S162/00; Y10S162/903
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
57 words
In an aqueous electroless plating solution containing a nickel salt, a tin salt and a hypophosphite, the improvement which comprises including in said solution thiourea in an amount of at least 1% by weight up to the saturation concentration of thiourea and maintaining the pH value of the solution in the range of about 2 to 5.
Claim 2
Dependent Claim
57 words
In an aqueous electroless plating solution containing a nickel salt, a tin salt and a hypophosphite, the improvement which comprises including in said solution thiourea in an amount of at least 1% by weight up to the saturation concentration of thiourea and maintaining the pH value of the solution in the range of about 2 to 5.
Claim 3
Dependent Claim
35 words
A solution according to claim 1, wherein the nickel salt and tin salt are each present in a concentration of about 0.25 to 5% by weight of the solution, based on nickel and tin respectively.
Claim 4
Dependent Claim
16 words
A bath according to claim 2 wherein the pH value is from about 2.5 to 4.0.
Claim 5
Dependent Claim
16 words
A bath according to claim 2, wherein the nickel salt is nickel sulfate or nickel chloride.
Claim 6
Dependent Claim
13 words
A bath according to claim 2, wherein the tin salt is stannous sulfate.
Claim 7
Dependent Claim
27 words
A bath according to claim 2, and additionally containing a soluble salt selected from a lead salt, a copper salt, a chromium salt and a zinc salt.
Claim 8
Dependent Claim
13 words
A bath according to claim 2, and including a source of iodide ions.
Claim 9
Dependent Claim
30 words
A bath according to claim 7, wherein the source of iodide ions comprises a soluble iodide salt in an amount by weight of at least twice the amount of thiourea.
Claim 10
Dependent Claim
35 words
A method of restoring a worn bronze Fourdrinier wire screen which comprises contacting said screen with said electroless plating solution as defined in claim 1 and forming a tin-nickel alloy electroless plating on said screen.
References Cited (Backward Citations)
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Cited
GB1009890A
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US3281266A
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US3265511A
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US3338741A
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US3485597A
Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-27 | 1980-01-26 | 1980-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-27 | 1984-01-26 | 1984-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-27 | 1988-01-26 | 1988-07-27 | $7700.00 | Window Closed / Lapsed |