US3721870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Capacitor
Assignee: Welwyn Electric Ltd
•
Filing: 1971-06-25
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Granted: 1973-03-20
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Expires: 1991-06-25
Abstract
Abstract The manufacture is described of capacitors having a very high capacitance value which is achieved by a very thin dielectric layer, said capacitors being constituted by (i) a layer of nickel or a nickel alloy, (ii) a layer of a cermet adapted to become electrically conductive and containing glass having a melting point less than that of layer (i), and (iii) a layer of a dielectric, said layer (iii) having been formed by chemical interaction of layer (i) with layer (ii) on firing to a temperature at which said interaction takes place, for a time sufficient to produce said layer (iii), the glass content of the cermet being at least 3 percent by weight but insufficient for the cermet itself to act as a dielectric.
Inventors
- 👤 J Edge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:28
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/018; H01G4/06; H01G4/08; H01G4/12; Y; Y10; Y10T; Y10T29/00; Y10T29/43; Y10T29/435
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
28 words
A dielectric construction according to claim 1, in which said first layer is an alloy selected from the class consisting of nickel-boron alloys, nickel-phosphorus alloys and nickel-phosphorus-coablt alloys.
Claim 2
Dependent Claim
21 words
A dielectric construction according to claim 1, in which the cermet layer contains at least 10 percent by weight of glass.
Claim 3
Dependent Claim
35 words
A dielectric construction according to claim 1, in which the cermet used is one having a constitution such that, after firing, it has a sheet resistivity of from 0.01 ohm to 106 ohm per square.
Claim 4
Dependent Claim
25 words
A construction in accordance with claim 1 wherein terminals are applied to said first and second layers whereby the construction is useful as a capacitor.
Claim 5
Dependent Claim
27 words
A capacitor according to claim 5, in which said first layer is an alloy selected from the class consisting of nickel-boron alloys, nickel-phosphorus alloys and nickel-phosphorus-cobalt alloys.
Claim 6
Dependent Claim
20 words
A capacitor according to claim 5, in which the cermet layer contains at least 10 percent by weight of glass.
Claim 7
Dependent Claim
30 words
A capacitor according to claim 5, in which the cermet used is one which, after firing, will have a sheet resistivity of from 0.01 ohm to 106 ohm per square.
Claim 8
Dependent Claim
146 words
A process for producing a construction characterized by dielectric properties comprising the steps of providing a first layer formed of a metal selected from the group consisting of nickel and alloys of nickel, applying a second layer to said first layer to form a composite, said second layer comprising a cermet capable of becoming electrically conductive upon firing and having a glass component having a melting point below the melting point of said first layer, said glass being contained in said second layer in an amount of at least three percent by weight but not exceeding the amount necessary for providing a specific resistivity of the cermet in excess of 106 ohm cm, and firing said composite at a temperature sufficient to produce a third layer of a dielectric comprising the reaction product developed at the interface of said first and second layers during such firing.
References Cited (Backward Citations)
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US3386856A
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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) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |