US4556587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for electro-magnetic interference shielding
Assignee: Shipley Co Inc
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Filing: 1983-12-19
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Granted: 1985-12-03
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Expires: 2003-12-19
Abstract
Abstract A process for metal plating plastic or elastomeric materials which produces a coating of high conductivity which does not reduce over time is disclosed in this application to provide electro-magnetic interference shielding for said materials. This process uses either a particular special plating bath containing stabilizer additions with any surface preparation technique, or a certain specific surface preparation technique along with the use of a standard plating bath or the special stabilized plating bath to obtain metal coatings with the desired properties.
Inventors
- 👤 Chris Tsiamis
- 👤 John E. McCaskie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:57
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/16; C23C18/18; C23C18/20; C23C18/22; C23C18/28
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
123 words
A process for EMI Shielding of plastic or elastomeric materials which comprises: (a) gas-etching the surface of said material by exposure to an atmosphere containing gaseous sulfur trioxide; (b) controlling the gas-etching reaction to a point where the surface will accept a deposit of an activating colloidal metal; (c) activating the etched surface by immersion into a solution containing a colloidal metal catalyst; and (d) plating the substrate with an electroless metal plating bath that contains an organic compound having a thiocarbonyl group in combination with a complexing agent capable of and in a sufficient amount to provide a metal coating which will provide a surface resistivity of less than about 1 ohm/square both initially and after aging for at least one month.
Claim 2
Dependent Claim
123 words
A process for EMI Shielding of plastic or elastomeric materials which comprises: (a) gas-etching the surface of said material by exposure to an atmosphere containing gaseous sulfur trioxide; (b) controlling the gas-etching reaction to a point where the surface will accept a deposit of an activating colloidal metal; (c) activating the etched surface by immersion into a solution containing a colloidal metal catalyst; and (d) plating the substrate with an electroless metal plating bath that contains an organic compound having a thiocarbonyl group in combination with a complexing agent capable of and in a sufficient amount to provide a metal coating which will provide a surface resistivity of less than about 1 ohm/square both initially and after aging for at least one month.
Claim 3
Dependent Claim
25 words
The process according to claim 1 wherein said atmosphere contains a sufficient amount of water vapor to improve the adhesion and/or coverage of the etching.
Claim 4
Dependent Claim
22 words
The process according to claim 1 wherein said activating step comprises immersing the etched material into a solution containing a metal colloid.
Claim 5
Dependent Claim
20 words
The process according to claim 3 wherein said metal colloid is a noble metal colloid or a transition metal colloid.
Claim 6
Dependent Claim
20 words
The process according to claim 4 wherein said noble metal colloid is a colloid of palladium, platinum, silver, or gold.
Claim 7
Dependent Claim
20 words
The process according to claim 4 wherein said transition metal colloid is a colloid of copper, nickel, cobalt, or iron.
Claim 8
Dependent Claim
57 words
The process according to claim 1 which comprises (b) treating the etched surface with a conditioning agent comprising a non-ionic surfactant to improve the surface for activation with a catalytic metal colloid, (c) depositing said activating colloid from a colloidal metal solution, and (d) plating a metal coating upon the activated surface from an electroless metal bath.
Claim 9
Dependent Claim
18 words
The process according to claim 7 in which the surface is cleaned with an alkaline solution after conditioning.
Claim 10
Dependent Claim
17 words
The process according to claim 8 in which the conditioning agent contains the alkaline or acid cleaner.
Claim 11
Dependent Claim
13 words
The process according to claim 16 in which the surface is subsequently neutralized.
Claim 12
Dependent Claim
16 words
The process according to claim 9 in which the surface is subsequently treated with an acid.
Claim 13
Dependent Claim
22 words
The process according to claim 7 in which the surfactant is a polyoxyalkylene or an adduct thereof or an alkyl phenol ethoxalate.
Claim 14
Dependent Claim
13 words
The process according to claim 1 wherein the electroless metal plating 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) | 1988-12-02 | 1989-06-03 | 1989-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-02 | 1993-06-03 | 1993-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-02 | 1997-06-03 | 1997-12-03 | $7700.00 | Window Closed / Lapsed |