Patent US4308570A successfully refreshed from Google Patents.
US4308570A
Expired / Lapsed
US
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High Q monolithic capacitor with glass-magnesium titanate body
Assignee: MRA Laboratories Inc
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Filing: 1980-02-25
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Granted: 1981-12-29
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Expires: 2000-02-25
Abstract
Abstract Monolithic capacitors having Q's of 3500 include copper electrodes buried in a non-reducible body that consists of a crystalline magnesium titanate phase and an intergranular glass phase. The crystalline phase contains magnesium meta-titanate and/or ortho-titanate. Magnesium di-titanate is excluded from the body as are the oxides of lead, bismuth and cadmium, which materials are reducible at the firing conditions necessary to preserve the integrity of the copper electrodes.
Inventors
- 👤 Ian Burn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:10
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/018; H01G4/06; H01G4/08; H01G4/12; H01G4/1209; H01G4/1218; H01G4/1227
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
96 words
A monolithic ceramic capacitor comprising a non-reducible glass-ceramic body having at room temperature a dielectric constant of about 10 and a Q at 1 MHz of greater than 1000, said body consisting of from 10% to 50% by weight of a non-reducible glass phase and from 50 to 90% by weight of a non-reducible crystalline ceramic phase, said ceramic phase being comprised of at least 85 mole percent magnesium titanate, a copper electrode being buried and cofired in said body and another electrode being in contact with said body and spaced from said buried copper electrode.
Claim 2
Dependent Claim
96 words
A monolithic ceramic capacitor comprising a non-reducible glass-ceramic body having at room temperature a dielectric constant of about 10 and a Q at 1 MHz of greater than 1000, said body consisting of from 10% to 50% by weight of a non-reducible glass phase and from 50 to 90% by weight of a non-reducible crystalline ceramic phase, said ceramic phase being comprised of at least 85 mole percent magnesium titanate, a copper electrode being buried and cofired in said body and another electrode being in contact with said body and spaced from said buried copper electrode.
Claim 3
Dependent Claim
20 words
The monolithic ceramic capacitor of claim 1 wherein said non-reducible ceramic phase is free of MgTi 2 O 5 .
Claim 4
Dependent Claim
15 words
The monolithic capacitor of claim 1 wherein said glass phase is an alkaline earth borate.
Claim 5
Dependent Claim
21 words
The monolithic capacitor of claim 1 wherein said ceramic phase additionally contains strontium up to 10 mole percent of said magnesium.
Claim 6
Dependent Claim
22 words
The monolithic ceramic capacitor of claim 1 wherein said ceramic phase additionally contains calcium up to 10 mole percent of said magnesium.
Claim 7
Dependent Claim
20 words
The monolithic ceramic capacitor of claim 1 wherein said non-reducible glass phase is substantially free of lead, bismuth and cadmium.
References Cited (Backward Citations)
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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) | 1984-12-28 | 1985-06-29 | 1985-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-28 | 1989-06-29 | 1989-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-28 | 1993-06-29 | 1993-12-29 | $7700.00 | Window Closed / Lapsed |