EP0112635A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Treatment of copper foil
Assignee: ELECTROFOILS TECHNOLOGY Ltd
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Filing: 1983-11-10
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Granted: —
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Expires: 2003-11-10
Abstract
Abstract A method of treating copper foil for use in the production of printed circuit boards to improve the adhesion of the foil to a base material includes the steps of depositing a nodular or dendritic layer of metal such as copper or zinc onto the foil and encapsulating said nodular or dendritic layer of metal with a layer of copper. A barrier layer is deposited over said encapsulating layer of copper, the barrier layer comprising an alloy of zinc, nickel and one or more of the metals lead, selenium, tellurium, tin or arsenic, the resultant structure then being passivated.
Inventors
- 👤 John Torday
- 👤 James Mcgilly
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 15:58
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/38; H05K3/382; H05K3/384; C; C25; C25D; C25D3/00; C25D3/02; C25D3/56; C25D3/565; C25D5/00; C25D5/10; C25D5/48; C25D5/60; C25D5/605; C25D5/611; C25D5/627; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0355; H05K2203/00; H05K2203/03; H05K2203/0307; H05K2203/07; H05K2203/0703; H05K2203/0723
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
72 words
A method of treating copper foil including the steps of depositing onto the foil a nodular or dendritic layer of metal and encapsulating said nodular or dendritic layer of metal with a layer of copper, characterised by the steps of applying over said encapsulating layer a barrier layer comprising an alloy of zinc, nickel and one or more of the metals lead, selenium, tellurium, tin or arsenic, and passivating the resultant structure.
Claim 2
Independent Claim
72 words
A method of treating copper foil including the steps of depositing onto the foil a nodular or dendritic layer of metal and encapsulating said nodular or dendritic layer of metal with a layer of copper, characterised by the steps of applying over said encapsulating layer a barrier layer comprising an alloy of zinc, nickel and one or more of the metals lead, selenium, tellurium, tin or arsenic, and passivating the resultant structure.
Claim 3
Dependent Claim
30 words
A method as claimed in claim 1 in which the barrier layer contains between 0.1% and 4% of lead and between 5% and 25% of nickel, the balance being zinc.
Claim 4
Dependent Claim
36 words
A method as claimed in claim 2 in which the barrier layer is electroplated from a bath containing nickel sulphate, zinc sulphate, ammonia, a citrate and lead in solution using a stainless steel or nickel anode.
Claim 5
Dependent Claim
30 words
A method as claimed in claim 2 in which the barrier layer is electroplated from a bath containing nickel sulphate, zinc sulphate, ammonia and a citrate using a lead anode.
Claim 6
Independent Claim
30 words
A method as claimed in any one of claims 1 to 4 in which passivation is achieved by means of chromate dipping or by cathodic electrolysis of a chromate solution.
Claim 7
Independent Claim
27 words
A method as claimed in any one of claims 1 to to 5 in which the nodular or dendritic layer deposited onto the copper foil is copper.
Claim 8
Independent Claim
26 words
A method as claimed in any one of claims 1 to 5 in which the nodular or dendritic layer deposited onto the copper foil is zinc.
Claim 9
Dependent Claim
25 words
A laminate comprising a dielectric substrate to which is bonded copper foil treated according to the method of any one of claims 1 to 7.
References Cited (Backward Citations)
No citation records indexed.
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