US4028116A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solution for electroless chrome alloy plating
Assignee: Individual
•
Filing: 1972-12-01
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Granted: 1977-06-07
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Expires: 1992-12-01
Abstract
Abstract There is herein disclosed an aqueous plating bath for electroless or catalytic deposition of chromium upon the surface of a substrate capable of accepting such deposition or which has been treated to provide a surface capable of accepting such deposition. The solution is characterized by the presence of chromium as an organic chromium compound such as chromium acetate or the equivalent in relatively high concentration, the presence of nickel as a nickel compound, such as nickel acetate or its equivalent in relatively low concentration only sufficient to render the deposit catalytic, together with the usual reducing and buffering compounds to which may be added a complexing reagent comprising the salts of oxalic acid all of which cooperate to produce a deposit substantially higher in chromium content than has heretofore been possible.
Inventors
- 👤 Curtis E. Cedarleaf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:06
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/16; C23C18/48
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
107 words
An aqueous solution for electroless or catalytic deposition of chromium alloy consisting essentially of an organic chromium salt having a concentration between about 10 to 40 grams per liter, a nickel salt having a concentration of not less than about 2 grams per liter and not more than about one-fifth the concentration of the chromium salt; a hypophosphite reducing agent having a concentration of between 5 and 30 grams per liter; a buffering compound capable of maintaining the pH of the solution between 3.5 and 6; and a complexing agent comprising a water soluble salt of oxalic acid in concentration about 1 to 5 grams per liter.
Claim 2
Dependent Claim
107 words
An aqueous solution for electroless or catalytic deposition of chromium alloy consisting essentially of an organic chromium salt having a concentration between about 10 to 40 grams per liter, a nickel salt having a concentration of not less than about 2 grams per liter and not more than about one-fifth the concentration of the chromium salt; a hypophosphite reducing agent having a concentration of between 5 and 30 grams per liter; a buffering compound capable of maintaining the pH of the solution between 3.5 and 6; and a complexing agent comprising a water soluble salt of oxalic acid in concentration about 1 to 5 grams per liter.
Claim 3
Dependent Claim
29 words
A solution as set forth in claim 1 containing a copper salt in an amount no greater than about 0.1 grams per liter to lend ductility to the deposit.
Claim 4
Dependent Claim
83 words
An aqueous solution for electroless deposition of chromium consisting essentially of an organic chromium salt having a concentration of about 25 grams per liter, a nickel salt having a concentration of about 4 grams per liter, a hypophosphite reducing agent having a concentration of about 25 grams per liter, a buffering compound capable of maintaining the pH of the solution at about 4.5, and a complexing agent comprising a water soluble salt of oxalic acid in concentration of about 5 grams per liter.
Claim 5
Dependent Claim
83 words
An aqueous solution for electroless deposition of chromium consisting essentially of an organic chromium salt having a concentration of about 25 grams per liter, a nickel salt having a concentration of about 4 grams per liter, a hypophosphite reducing agent having a concentration of about 25 grams per liter, a buffering compound capable of maintaining the pH of the solution at about 4.5, and a complexing agent comprising a water soluble salt of oxalic acid in concentration of about 5 grams per liter.
Claim 6
Dependent Claim
77 words
A solution as set forth in claim 1 wherein the chromium salt is chromium acetate, the nickel salt is nickel acetate, the reducing agent is a hypophosphite taken from the group comprising sodium and potassium hypophosphite, the buffering agent is an acetate selected from the group comprising sodium or potassium acetate, sodium or potassium hydroxyacetate and sodium or potassium amino acetate and the complexing agent comprises an oxalate selected from the group comprising sodium and potassium oxalate.
Claim 7
Dependent Claim
39 words
A solution as set forth in claim 3 wherein the chromium salt is chromium acetate, the nickel salt is nickel acetate, the hypophosphite is sodium hypophosphite, the buffering compound is sodium acetate and the complexing agent is sodium oxalate.
References Cited (Backward Citations)
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US3178311A
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US3226924A
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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) | 1980-06-06 | 1980-12-06 | 1981-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-06 | 1984-12-06 | 1985-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-06 | 1988-12-06 | 1989-06-07 | $7700.00 | Window Closed / Lapsed |