Patent US4607315A successfully refreshed from Google Patents.
US4607315A
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Low temperature sintered ceramic capacitor with high DC breakdown voltage, and method of manufacture
Assignee: Taiyo Yuden Co Ltd
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Filing: 1985-12-04
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Granted: 1986-08-19
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Expires: 2005-12-04
Abstract
Abstract A monolithic ceramic capacitor having a higher DC breakdown voltage per unit thickness of the dielectric ceramic body than heretofore. The major ingredient of the ceramic is expressed as {(Ba 1-x-y Ca x Sr y )O} k (Ti 1-z Zr z )O 2 , where x, y, z and k are numerals in the ranges specified herein. To this major ingredient is added a minor proportion of a mixture of boric oxide and silicon dioxide in specified ranges of proportions. For the fabrication of capacitors having dielectric bodies of the above composition, the moldings of the mixture of the major ingredient and additives in the specified proportions are sintered to maturity in a reductive or neutral atmosphere and then reheated at a lower temperature in an oxidative atmosphere. The sintering temperature can be so low (1000°-1200° C.) that the moldings can be cosintered with base metal electrodes buried therein.
Inventors
- 👤 Takeshi Wada
- 👤 Hiroshi Kishi
- 👤 Shunji Murai
- 👤 Masami Fukui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:35
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/018; H01G4/06; H01G4/08; H01G4/12; H01G4/1209; H01G4/1236; H01G4/1245; C; C04; C04B; C04B35/00; C04B35/01; C04B35/46; C04B35/462; C04B35/465; C04B35/468; C04B35/4682; H01B; H01B3/00; H01B3/02; H01B3/12
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
131 words
A solid dielectric capacitor comprising a dielectric ceramic body and at least two electrodes in contact therewith, the dielectric ceramic body consisting essentially of: 100 parts by weight of a major ingredient expressed by the formula, {(Ba.sub.1-x-y Ca.sub.x Sr.sub.y)O}.sub.k (Ti.sub.1-z Zr.sub.z)O.sub.2, where x is a numeral in the range of 0.02 to 0.27; y is a numeral greater than zero and not more than 0.37; z is a numeral greater than zero and not more than 0.26; k is a numeral in the range of 1.00 to 1.04; and (1-x-y) has a value not less than 0.60 and less than 0.98; and from 0.2 to 10.0 parts by weight of an additive mixture of from 25 to 90 mole percent boric oxide and from 10 to 75 mole percent silicon dioxide.
Claim 2
Dependent Claim
131 words
A solid dielectric capacitor comprising a dielectric ceramic body and at least two electrodes in contact therewith, the dielectric ceramic body consisting essentially of: 100 parts by weight of a major ingredient expressed by the formula, {(Ba.sub.1-x-y Ca.sub.x Sr.sub.y)O}.sub.k (Ti.sub.1-z Zr.sub.z)O.sub.2, where x is a numeral in the range of 0.02 to 0.27; y is a numeral greater than zero and not more than 0.37; z is a numeral greater than zero and not more than 0.26; k is a numeral in the range of 1.00 to 1.04; and (1-x-y) has a value not less than 0.60 and less than 0.98; and from 0.2 to 10.0 parts by weight of an additive mixture of from 25 to 90 mole percent boric oxide and from 10 to 75 mole percent silicon dioxide.
Claim 3
Dependent Claim
20 words
The solid dielectric capacitor as set forth in claim 1, wherein the electrodes are buried in the dielectric ceramic body.
Claim 4
Dependent Claim
18 words
The solid dielectric capacitor as set forth in claim 1, wherein the electrodes are of a base metal.
Claim 5
Dependent Claim
16 words
The solid dielectric capacitor as set forth in claim 3, wherein the base metal is nickel.
Claim 6
Dependent Claim
27 words
The solid dielectric capacitor as set forth in claim 1, wherein the dielectric ceramic body has a DC breakdown voltage of at least 25 volts per micron.
Claim 7
Dependent Claim
178 words
A process for the manufacture of a solid dielectric capacitor providing a mixture of: (a) 100 parts by weight of {(Ba 1-x-y Ca x Sr y )O} k (Ti 1-z Zr z )O 2 in finely divided form, where x is a numeral in the range of 0.02 to 0.27; y is a numeral greater than zero and not more than 0.37; z is a numeral greater than zero and not more than 0.26; k is a numeral in the range of 1.00 to 1.04; and (1-x-y) has a value not less than 0.60 and less than 0.98; and (b) from 0.2 to 10.0 parts by weight of an additive mixture of from 25 to 90 mole percent boric oxide and from 10 to 75 mole percent silicon dioxide in finely divided form; molding the mixture into desired shape and size, the molding having at least two electrode portions of an electroconductive material; cosintering the molding and the electrode portions to maturity in a nonoxidative atmosphere; and reheating the sintered molding and electrode portions in an oxidative atmosphere.
Claim 8
Dependent Claim
178 words
A process for the manufacture of a solid dielectric capacitor providing a mixture of: (a) 100 parts by weight of {(Ba 1-x-y Ca x Sr y )O} k (Ti 1-z Zr z )O 2 in finely divided form, where x is a numeral in the range of 0.02 to 0.27; y is a numeral greater than zero and not more than 0.37; z is a numeral greater than zero and not more than 0.26; k is a numeral in the range of 1.00 to 1.04; and (1-x-y) has a value not less than 0.60 and less than 0.98; and (b) from 0.2 to 10.0 parts by weight of an additive mixture of from 25 to 90 mole percent boric oxide and from 10 to 75 mole percent silicon dioxide in finely divided form; molding the mixture into desired shape and size, the molding having at least two electrode portions of an electroconductive material; cosintering the molding and the electrode portions to maturity in a nonoxidative atmosphere; and reheating the sintered molding and electrode portions in an oxidative atmosphere.
Claim 9
Dependent Claim
35 words
The process for the fabrication of a solid dielectric capacitor as set froth in claim 6, wherein the electrode portions are formed on the molding by coating a paste composed principally of a base metal.
Claim 10
Dependent Claim
22 words
The process for the fabrication of a solid dielectric capacitor as set forth in claim 7, wherein the base metal is nickel.
Claim 11
Dependent Claim
34 words
The process for the fabrication of a solid dielectric capacitor as set forth in claim 6, wherein the molding and the electrode portions are cosintered in a temperature range of 1000° to 1200° C.
Claim 12
Dependent Claim
34 words
The process for the fabrication of a solid dielectric capacitor as set forth in claim 9, wherein the sintered molding and electrode portions are reheated in a temperature range of 500° to 1000° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-08-18 | 1990-02-17 | 1990-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-18 | 1994-02-17 | 1994-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-18 | 1998-02-17 | 1998-08-19 | $7700.00 | Window Closed / Lapsed |