Patent US4707394A successfully refreshed from Google Patents.
US4707394A
Expired / Lapsed
US
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Method for producing circuit boards with deposited metal patterns and circuit boards produced thereby
Assignee: Firan Corp
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Filing: 1986-09-19
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Granted: 1987-11-17
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Expires: 2006-09-19
Abstract
Abstract A process for producing circuit boards involves the coating of a resinous substrate with a fluid mixture of an epoxy polymer component and a rubber polymer which is interactive therewith at temperatures of at least 180° F. Preferably the rubber is a low molecular weight polyfunctional reactive butadiene/acrylonitrile interpolymer which is terminated by vinyl or carboxyl functional groups. The rubber component comprises at least 70 percent by weight of the epoxy polymer component, and the coating has a thickness of 0.001-0.015 inch. The coating is partially cured to effect partial polymerization of the epoxy prepolymer, further polymerization of the rubber, if it is low molecular weight, and interaction of the rubber and epoxy polymer to form a matrix of the interacted rubber/epoxy. The exposed surface of this coating is then etched, and metal is deposited on the surface to form a conductive layer. A conductive pattern is formed therein, and heat and pressure are then applied to the conductive pattern and coating to fully cure the coating and bond the coating to the metal layer, and thus the conductive pattern to the resinous substrate. The metal layer may be deposited chemically or by vacuum metallizing and like techniques.
Inventors
- 👤 Peter R. Chant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:33
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/10; H05K3/107; H05K3/38; H05K3/386; H05K3/387; H05K2201/00; H05K2201/01; H05K2201/0104; H05K2201/0133; H05K2201/03; H05K2201/0332; H05K2201/0364; H05K2201/0376; H05K2203/00; H05K2203/02; H05K2203/0278; H05K2203/06; H05K2203/066; H05K2203/09; H05K2203/095; H05K2203/11; H05K2203/1105; H05K3/108; H05K3/18; H05K3/181; H05K3/388; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49155; Y10T428/00; Y10T428/12; Y10T428/12389; Y10T428/12396; Y10T428/24; Y10T428/24802; Y10T428/24917; Y10T428/31504; Y10T428/31511; Y10T428/31515; Y10T428/31522
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
205 words
In a process for producing circuit boards having a metallized circuit pattern firmly bonded to a resinous substrate, the steps comprising: (a) coating a resinous substrate with a fluid mixture of a formulation containing: (i) a low molecular weight polyfunctional reactive rubber component comprising an interpolymer of butadiene and acrylonitrile; and (ii) an epoxy polymer component, said components being interactive at temperatures of at least 180° F., said rubber component comprising 70-200 percent by weight of the epoxy polymer component, said coating having a thickness of 0.0005-0.015 inch; (b) partially curing the coating to produce partial cross-linking of said epoxy polymer component, further polymerization of the rubber, and interaction of said rubber and epoxy polymer components; (c) etching the exposed surface of the coating to produce a microporous surface; (d) depositing metal on the microporous surface of the coating to form a conductive layer with microformations extending into the recesses of said microporous surface; (e) electrodepositing metal on said conductive layer to form a conductive pattern therewith; and (f) applying heat and pressure to said conductive pattern and coating to fully cure said coating, thereby firmly bonding said coating to said metal layer and thereby said conductive pattern through said coating to said resinous substrate.
Claim 2
Dependent Claim
205 words
In a process for producing circuit boards having a metallized circuit pattern firmly bonded to a resinous substrate, the steps comprising: (a) coating a resinous substrate with a fluid mixture of a formulation containing: (i) a low molecular weight polyfunctional reactive rubber component comprising an interpolymer of butadiene and acrylonitrile; and (ii) an epoxy polymer component, said components being interactive at temperatures of at least 180° F., said rubber component comprising 70-200 percent by weight of the epoxy polymer component, said coating having a thickness of 0.0005-0.015 inch; (b) partially curing the coating to produce partial cross-linking of said epoxy polymer component, further polymerization of the rubber, and interaction of said rubber and epoxy polymer components; (c) etching the exposed surface of the coating to produce a microporous surface; (d) depositing metal on the microporous surface of the coating to form a conductive layer with microformations extending into the recesses of said microporous surface; (e) electrodepositing metal on said conductive layer to form a conductive pattern therewith; and (f) applying heat and pressure to said conductive pattern and coating to fully cure said coating, thereby firmly bonding said coating to said metal layer and thereby said conductive pattern through said coating to said resinous substrate.
Claim 3
Dependent Claim
20 words
The process in accordance with claim 1 wherein said rubber interpolymer has terminal functional groups selected from vinyl and carboxyl.
Claim 4
Dependent Claim
21 words
The process in accordance with claim 1 wherein said rubber interpolymer has a Brookfield viscosity of 100-400,000 cps at 27° C.
Claim 5
Dependent Claim
21 words
The process in accordance with claim 1 wherein said functional terminal groups interact with the epoxy polymer component during curing thereof.
Claim 6
Dependent Claim
28 words
The process in accordance with claim 1 wherein said etching step utilizes a chemical etchant to attack the exposed surface of said coating and produce the microporous characteristic.
Claim 7
Dependent Claim
27 words
The process in accordance with claim 1 wherein said etching step utilizes a plasma to attack the exposed surface of said coating and produce the microporous characteristic.
Claim 8
Dependent Claim
19 words
The process in accordance with claim 1 wherein said metal layer is deposited by a process of vacuum metallizing.
Claim 9
Dependent Claim
21 words
The process in accordance with claim 1 wherein said metal layer is deposited by electroless chemical deposition from a metallic solution.
Claim 10
Dependent Claim
30 words
The process in accordance with claim 1 wherein said terminal functional group is a vinyl group and wherein said rubber component comprises 100-200% by weight of the epoxy prepolymer component.
Claim 11
Dependent Claim
60 words
The process in accordance with claim 1 wherein said step of partially curing the coating comprises developing a temperature of 250-350° F. in the coating for a period of at least 2 hours, and wherein said step of fully curing the coating comprises developing a temperature in the coating of 280-350° F. for a period of at least 2 hours.
Claim 12
Dependent Claim
27 words
The process in accordance with claim 1 wherein said terminal step of applying heat and pressure at least partially embeds the metallic conductive pattern in the coating.
Claim 13
Dependent Claim
34 words
The process in accordance with claim 1 wherein a continuous layer of metal is initially deposited on said coating and thereafter selectively etched to remove said layer between said elements of said conductive pattern.
Claim 14
Dependent Claim
222 words
In a process for producing circuit boards having a metallized circuit pattern firmly bonded to a resinous substrate, the steps comprising: (a) coating a resinous substrate with a fluid mixture of a formulation containing a rubber component and an epoxy polymer component which are interactive at temperatures of at least 180° F., said rubber component comprising 70-200 percent by weight of the epoxy polymer component, said coating having a thickness of 0.0005-0.015 inch; (b) partially curing the coating to produce partial cross-linking of said epoxy polymer component, and interaction of said rubber and epoxy polymer components to form a matrix of the interacted rubber and epoxy components; (c) etching the exposed surface of the coating to produce a microporous surface; (d) depositing metal on said microporous surface of the coating to form a conductive layer with microformations extending into the recesses of said microporous surface; (e) electrodepositing metal on said conductive layer to form a conductive pattern therewith; and (f) applying heat and pressure to said conductive pattern and coating to fully cure said coating, thereby firmly bonding said coating to said metal layer and thereby said conductive pattern through said coating to said resinous substrate, said heat and pressure embedding said conductive pattern in said coating to a depth of at least 10 percent of the thickness of the conductive pattern.
Claim 15
Dependent Claim
222 words
In a process for producing circuit boards having a metallized circuit pattern firmly bonded to a resinous substrate, the steps comprising: (a) coating a resinous substrate with a fluid mixture of a formulation containing a rubber component and an epoxy polymer component which are interactive at temperatures of at least 180° F., said rubber component comprising 70-200 percent by weight of the epoxy polymer component, said coating having a thickness of 0.0005-0.015 inch; (b) partially curing the coating to produce partial cross-linking of said epoxy polymer component, and interaction of said rubber and epoxy polymer components to form a matrix of the interacted rubber and epoxy components; (c) etching the exposed surface of the coating to produce a microporous surface; (d) depositing metal on said microporous surface of the coating to form a conductive layer with microformations extending into the recesses of said microporous surface; (e) electrodepositing metal on said conductive layer to form a conductive pattern therewith; and (f) applying heat and pressure to said conductive pattern and coating to fully cure said coating, thereby firmly bonding said coating to said metal layer and thereby said conductive pattern through said coating to said resinous substrate, said heat and pressure embedding said conductive pattern in said coating to a depth of at least 10 percent of the thickness of the conductive pattern.
Claim 16
Dependent Claim
26 words
The process in accordance with claim 13 wherein said rubber has functional terminal groups which interact with the epoxy prepolymer components during said metal curing step.
Claim 17
Dependent Claim
28 words
The process in accordance with claim 13 wherein said etching step utilizes a chemical etchant to attack the exposed surface of said coating and produce the microporous characteristic.
Claim 18
Dependent Claim
19 words
The process in accordance with claim 13 wherein said metal layer is deposited by a process of vacuum metallizing.
Claim 19
Dependent Claim
48 words
The process in accordance with claim 13 wherein said rubber component is a low molecular weight polyfunctional reactive rubber comprising an interpolymer of butadiene and acrylonitrile which is terminated by a functional vinyl group and wherein said rubber component comprises 100-200% by weight of the epoxy polymer component.
Claim 20
Dependent Claim
20 words
The process in accordance with claim 17 wherein said rubber interpolymer has terminal functional groups selected from vinyl and carboxyl.
Claim 21
Dependent Claim
125 words
In a circuit board, the combination comprising: (a) a resinous substrate; (b) an intermediate coating on one surface of said substrate of about 0.0005-0.015 inch and containing a rubber component and an epoxy polymer which have interacted to provide a matrix of the interacted rubber/epoxy polymer, said rubber component comprising at least 35 percent by weight of said coating; and (c) a metal conductive pattern on said coating providing a circuit, said conductive pattern having a base layer which microformations at the interface with said coating and extending thereinto, said conductive pattern being embedded in said coating to a depth of at least 10 percent of its thickness, said coating being firmly bonded to said metal layer and thereby through said coating to said substrate.
Claim 22
Dependent Claim
125 words
In a circuit board, the combination comprising: (a) a resinous substrate; (b) an intermediate coating on one surface of said substrate of about 0.0005-0.015 inch and containing a rubber component and an epoxy polymer which have interacted to provide a matrix of the interacted rubber/epoxy polymer, said rubber component comprising at least 35 percent by weight of said coating; and (c) a metal conductive pattern on said coating providing a circuit, said conductive pattern having a base layer which microformations at the interface with said coating and extending thereinto, said conductive pattern being embedded in said coating to a depth of at least 10 percent of its thickness, said coating being firmly bonded to said metal layer and thereby through said coating to said substrate.
Claim 23
Dependent Claim
219 words
The circuit board in accordance with claim 19 which is produced by a process comprising the steps of: (a) coating a resinous substrate with a fluid mixture of a formulation containing a rubber component and an epoxy polymer component which are interactive at temperatures of at least 180° F., said rubber component comprising 70-200 percent by weight of the epoxy polymer component, said coating having a thickness of 0.0005-0.015 inch; (b) partially curing the coating to produce partial cross-linking of said epoxy polymer component, and interaction of said rubber and epoxy polymer components to form a matrix of the interacted rubber and epoxy components; (c) etching the exposed surface of the coating to produce a microporous surface; (d) depositing metal on said microporous surface of the coating to form a conductive layer with microformations extending into the recesses of said microporous surface; (e) electrodepositing metal on said conductive layer to form a conductive pattern therewith; and (f) applying heat and pressure to said conductive pattern and coating to fully cure said coating, thereby firmly bonding said coating to said metal layer and thereby said conductive pattern through said coating to said resinous substrate, said heat and pressure embedding said conductive pattern in said coating to a depth of at least 10 percent of the thickness of the conductive pattern.
Claim 24
Dependent Claim
19 words
The circuit board of claim 20 wherein said rubber interpolymer has terminal functional groups selected from vinyl and carboxyl.
Claim 25
Dependent Claim
20 words
The circuit board of claim 20 wherein said rubber interpolymer has a Brookfield viscosity of 100-400,000 cps at 27° C.
Claim 26
Dependent Claim
47 words
The circuit board of claim 20 wherein said rubber component is a low molecular weight polyfunctional reactive rubber comprising an interpolymer of butadiene and acrylonitrile which is terminated by a functional vinyl group and wherein said rubber component comprises 100-200% by weight of the epoxy polymer component.
Claim 27
Dependent Claim
20 words
The circuit board of claim 19 wherein said rubber component comprises at least 50 percent by weight of said coating.
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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) | 1990-11-16 | 1991-05-18 | 1991-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-16 | 1995-05-18 | 1995-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-16 | 1999-05-18 | 1999-11-17 | $7700.00 | Window Closed / Lapsed |