US4169171A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bright electroless plating process and plated articles produced thereby
Assignee: MacDermid Enthone Inc
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Filing: 1978-02-13
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Granted: 1979-09-25
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Expires: 1998-02-13
Abstract
Abstract An adherent bright metallic coating which may be any metal or alloy capable of being deposited electrolessly, is applied to the surface of a plastic or other dielectric part (or to a metal part) by an electroless process comprising suitable pretreatment of said surface, deposition of a primary electroless copper to produce an underlayer, then depositing a bright secondary electroless coating of the desired metal (the overlayer) with complete elimination of any subsequent electroplating process [usually required to achieve this brightness]. The required overlayer may also be limited to selected surface areas of a coated part by mechanically removing portions of the primary electroless copper prior to immersion of the part in the secondary electroless bath to produce the desired overlayer metal.
Inventors
- 👤 Harold Narcus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 01:02
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/16; C23C18/1601; C23C18/1633; C23C18/1646; C23C18/165; C23C18/1651; C23C18/18; C23C18/20; C23C18/2006; C23C18/2046; C23C18/2073; C23C18/2086; C23C18/31; C23C18/32; C23C18/34; C23C18/36; H; H05; H05K; H05K3/00; H05K3/22; H05K3/24; H05K3/244; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9335; Y10S428/936
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
108 words
Method of electroless metal coating to produce a bright metal of high reflectivity and adhesion comprising, treating a substrate surface to prepare it for electroless coating, then treating the entirety of said surface with a primary electroless copper coating solution maintained at a basic pH of 11.5-13.5 and containing a copper chelating agent, and coating the surface with copper at 0.2-0.4 mils per hour, then treating the said surface with a secondary electroless metal coating solution maintained at its characteristic electroless coating pH, the secondary solution comprising sufficient phosphorus and being controlled to produce 6-12 weight percent phosphorus in the final coating produced from the secondary coating solution.
Claim 2
Dependent Claim
108 words
Method of electroless metal coating to produce a bright metal of high reflectivity and adhesion comprising, treating a substrate surface to prepare it for electroless coating, then treating the entirety of said surface with a primary electroless copper coating solution maintained at a basic pH of 11.5-13.5 and containing a copper chelating agent, and coating the surface with copper at 0.2-0.4 mils per hour, then treating the said surface with a secondary electroless metal coating solution maintained at its characteristic electroless coating pH, the secondary solution comprising sufficient phosphorus and being controlled to produce 6-12 weight percent phosphorus in the final coating produced from the secondary coating solution.
Claim 3
Dependent Claim
32 words
The method of claim 1 wherein the overlayer coating solutions contain AH 2 PO 2 .H 2 O where A is selected from the class consisting of alkali metal and ammonium ions.
Claim 4
Dependent Claim
29 words
The method of claim 1 wherein a portion of the primary copper layer is removed prior to treating the primary nickel coated substrate with the secondary electroless coating solution.
Claim 5
Dependent Claim
17 words
The method of claim 1 wherein both primary and secondary treating steps comprise immersion of the substrate.
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein the substrate preparation treatment comprises etching, catalyst deposition for activation and acceleration by surface attack.
Claim 7
Dependent Claim
113 words
Method of nickel coating comprising, etching and activating the surface of one or more substrate articles in a single step, acceleration treatment of the substrate surfaces, immersing of the substrates in a primary copper solution maintained at 25°-35° C. and pH of 11.5-13.5 for 5-15 minutes to produce a primary copper coating thereon at 0.2-0.4 mils per hour, and then immersing the substrate without rinsing or neutralization, into a secondary electroless metal coating solution maintained at temperature and pH to produce a self building brightening of the surfaces, the secondary solution comprising sufficient phosphorus and being controlled to produce 6-12 weight percent phosphorus in the final coating produced from the secondary coating solution.
Claim 8
Dependent Claim
113 words
Method of nickel coating comprising, etching and activating the surface of one or more substrate articles in a single step, acceleration treatment of the substrate surfaces, immersing of the substrates in a primary copper solution maintained at 25°-35° C. and pH of 11.5-13.5 for 5-15 minutes to produce a primary copper coating thereon at 0.2-0.4 mils per hour, and then immersing the substrate without rinsing or neutralization, into a secondary electroless metal coating solution maintained at temperature and pH to produce a self building brightening of the surfaces, the secondary solution comprising sufficient phosphorus and being controlled to produce 6-12 weight percent phosphorus in the final coating produced from the secondary coating solution.
Claim 9
Dependent Claim
30 words
Method of nickel coating in accordance with claim 6 wherein a portion of the primary coating is removed prior to the said second immersion of the substrates into nickel solution.
Claim 10
Dependent Claim
43 words
Method in accordance with claim 6 wherein said primary copper solution comprises copper sulfate and a basic mixture including glacial acetic acid and ammonium hydroxide and said secondary metal solution comprises sulphate salt of the metal, sodium hypophosphite and a weak acid mixture.
Claim 11
Dependent Claim
107 words
Method of electroless metal coating to produce a bright metal of high reflectivity and adhesion comprising, treating a nonconductive substrate to prepare it for electroless coating, then applying a primary copper underlayer to the substrate by simultaneous reduction of a copper compound while dissolved in an electroless bath in contact with the substrate while chelating copper ions therein and at a rate of 0.2-0.4 mils per hour, then applying a secondary metal coating to the said copper surfaced substrate by electroless coating, the secondary solution comprising sufficient phosphorus and being controlled to produce 6-12 weight percent phosphorus in the final coating produced from the secondary coating solution.
Claim 12
Dependent Claim
107 words
Method of electroless metal coating to produce a bright metal of high reflectivity and adhesion comprising, treating a nonconductive substrate to prepare it for electroless coating, then applying a primary copper underlayer to the substrate by simultaneous reduction of a copper compound while dissolved in an electroless bath in contact with the substrate while chelating copper ions therein and at a rate of 0.2-0.4 mils per hour, then applying a secondary metal coating to the said copper surfaced substrate by electroless coating, the secondary solution comprising sufficient phosphorus and being controlled to produce 6-12 weight percent phosphorus in the final coating produced from the secondary coating solution.
Claim 13
Dependent Claim
19 words
The method of claim 9 wherein the primary electroless coating utilizes an organic reducing agent compound having multiple bonds.
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) | 1982-09-24 | 1983-03-26 | 1983-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-24 | 1987-03-26 | 1987-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-24 | 1991-03-26 | 1991-09-25 | $7700.00 | Window Closed / Lapsed |