EP0086656A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Glass-ceramic articles having metallic surfaces and manufacture thereof
Assignee: Corning Glass Works
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Filing: 1983-02-15
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Granted: —
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Expires: 2003-02-15
Abstract
Abstract Composite aticles composed of a substrate consisting of a machinable glass-ceramic and an integral, electrically-conductive surface layer consisting of metallic copper and/or silver are prepared by heat treating precursor glass bodies containing copper and/or silver ions to grow fluormica crystals therein, thereby producing glass-ceramics, and to cause migration of the copper and/or silver ions to the surface thereof which are reduced to metallic copper and/or silver via heat treating in a reducing atmosphere. Where desired, holes can be bored, drilled, or punched into the glass-ceramic prior to exposure to the reducing heat treatment such that, upon heat treatment in a reducing environment, the sides of the holes will become metal plated.
Inventors
- 👤 Syed Nurul Hoda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 13:01
CPC Classifications
C; C03; C03C; C03C10/00; C03C10/16; C03C23/00; H; H05; H05K; H05K3/00; H05K3/10; H05K3/105
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
27 words
A composite article composed of a substrate consisting of a glass-ceramic which is mechanically machinable and an integral, electrically-conductive surface layer consisting of metallic copper and/or silver.
Claim 2
Dependent Claim
27 words
A composite article composed of a substrate consisting of a glass-ceramic which is mechanically machinable and an integral, electrically-conductive surface layer consisting of metallic copper and/or silver.
Claim 3
Dependent Claim
37 words
A composite article as claimed in claim 1 characterised in that the predominant crystal phase present in the glass-ceramic substrate is a synthetic fluormica selected from normal fluorophlogopite, alkali metal boron fluorophlogopite, and alkaline earth metal fluorophlogopite.
Claim 4
Dependent Claim
94 words
A composite article as claimed in claim 1 or claim 2 characterised in that the glass-ceramic substrate consists essentially, expressed in terms of weight percent on the oxide basis of 6 - 22% MgO, 10 - 18% MgF 2 , an effective amount up to 6% Cu 2 O and/or Ag 2 0, 0 - 14% K 2 0, 0 - 16% BaO, 0 - 12% SrO, 0 - 10% CaO, 0 - 22% Al 2 O 3 , 0 - 18% B 2 O 3 , and 30 - 47% Si0 2 .
Claim 5
Dependent Claim
149 words
A method for making a composite article as claimed in claim 1 characterised in that: (1) one melts a batch for a glass of the proper composition containing an effective amount of copper and/or silver compound; (2) one simultaneously cools the melt to a temperature at least within the transformation range thereof and shaping a glass article of a desired configuration therefrom; (3) one exposes the glass article to a temperature between 700° - 1200°C for a period of time sufficient to cause the growth of synthetic fluormica crystals in situ, thereby producing a glass-ceramic body and to effect migration of copper and/or silver ions to the surface thereof; and (4) one exposes the glass-ceramic body to a dry reducing environment at a temperature between 500°C - 1000°C for a period of time sufficient to reduce the copper and/or silver ions in said surface to metallic copper and/or silver.
Claim 6
Dependent Claim
35 words
A method as claimed in claim 4 characterised in that the predominant crystal phase present in the glass-ceramic is a synthetic fluormica selected from normal fluorophlogopite, alkali metal boron fluorophlogopite, and alkaline earth metal fluorophlogopite.
Claim 7
Dependent Claim
88 words
A method as claimed in claim 4 or claim 5 characterised in that the glass consists essentially, expressed in terms of weight percent on the oxide basis, of 6 - 22% MgO. 10 - 18% MgF 2 , an effective amount up to 6% Cu 2 O and/or Ag 2 O, 0 - 14% K 2 0. 0 - 16% BaO, 0 - 12% SrO, 0 - 10% CaO, 0 - 22% A1 2 03, 0 - 18% B20 3 , and 30 - 47% SiO 2 .
Claim 8
Dependent Claim
90 words
A method as claimed in claim 4 characterised in that the predominant crystal phase in the glass-ceramic body is an alkali metal boron fluorophlogopite and the glass article is exposed to a temperature of 900°C - 1000°C in a dry reducing environment for a period of time sufficient to cause the growth of alkali metal boron fluorophlogopite crystals in situ, thereby producing a glass-ceramic body, to effect migration of copper and/or silver ions to the surface thereof, and to reduce said copper and/or silver ions to metallic copper and/or silver.
Claim 9
Dependent Claim
105 words
A method as claimed in claim 4 characterised in that the glass article is exposed to a temperature between 700° - 1200°C in an oxidizing-environment for a period of time sufficient to cause the growth of crystals in situ, thereby producing a glass-ceramic body and effecting migration of copper and/or silver ions to the surface thereof and the development of a layer of copper oxide and/or silver oxide, and thereafter exposing said glass-ceramic body to a dry reducing environment at a temperature between 500° - 1000°C for a period of time sufficient to reduce the copper oxide and/or silver oxide to metallic copper and/or silver.
Claim 10
Independent Claim
49 words
A method as claimed in any of claims 4 to 8 characterised in that, after the glass-ceramic body has been produced and prior to exposing said body to a dry reducing environment, at least one hole is made therein and the body then exposed to said dry reducing atmosphere.
Claim 11
Dependent Claim
24 words
A composite article as claimed in claim 1 in the form of a printed circuit board having holes therein with integral, electrically conductive films.
References Cited (Backward Citations)
No citation records indexed.
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