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Multilayer ceramic capacitors

Assignee: EIDP Inc
•
Filing: 1977-12-13
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Granted: 1980-10-14
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Expires: 1997-12-13
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Abstract

Abstract Multilayer capacitors of good electrical properties can be made by firing, in air at low temperatures, certain modified lead titanate dielectric compositions. The dielectric compositions have the formula (Sr.sub.x Pb.sub.1-x TiO.sub.3).sub.a (PbMg.sub.0.5 W.sub.0.5 O 3 ) b wherein x is 0-0.10, a is 0.35-0.5, b is 0.5-0.65, and a plus b equals one.

Inventors

  • 👤 Robert J. Bouchard
  • 👤 Lothar H. Brixner
  • 👤 Michael J. Popowich

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 08:56
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/46; C04B35/462; C04B35/465; C04B35/47; H; H01; H01B; H01B3/00; H01B3/02; H01B3/12; H01G; H01G4/00; H01G4/002; H01G4/018; H01G4/06; H01G4/08; H01G4/12; H01G4/1209; H01G4/1254; H01G4/1263

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 137 words
A monolithic ceramic capacitor comprising a plurality of superimposed alternating layers of a dielectric composition and metal electrodes bonded together into a unitary body, the capacitor having a dielectric constant of at least 1000 and a dissipation factor of less than 5% and exhibiting a change in capacitance, at room temperature with time of about 1.5% or less per decade in hours even at a dielectric constant of 4000, the capacitor having been fired at a low temperature of 1050° C. or less in air, the electrodes being substantially embedded in the dielectric and having a melting point less than about 1050° C., the dielectric composition having the formula (Sr.sub.x Pb.sub.1-x TiO.sub.3).sub.a (PbMg.sub.0.5 W.sub.0.5 O.sub.3).sub.b wherein x is 0-0.10, a is 0.35-0.5, b is 0.5-0.65, and a plus b equals one and the metal electrodes comprise silver.
Claim 2
Dependent Claim 137 words
A monolithic ceramic capacitor comprising a plurality of superimposed alternating layers of a dielectric composition and metal electrodes bonded together into a unitary body, the capacitor having a dielectric constant of at least 1000 and a dissipation factor of less than 5% and exhibiting a change in capacitance, at room temperature with time of about 1.5% or less per decade in hours even at a dielectric constant of 4000, the capacitor having been fired at a low temperature of 1050° C. or less in air, the electrodes being substantially embedded in the dielectric and having a melting point less than about 1050° C., the dielectric composition having the formula (Sr.sub.x Pb.sub.1-x TiO.sub.3).sub.a (PbMg.sub.0.5 W.sub.0.5 O.sub.3).sub.b wherein x is 0-0.10, a is 0.35-0.5, b is 0.5-0.65, and a plus b equals one and the metal electrodes comprise silver.
Claim 3
Dependent Claim 18 words
A capacitor according to claim 1 where in the dielectric composition a is 0.35-0.45 and b is 0.55-0.65.
Claim 4
Dependent Claim 13 words
A capacitor according to claim 1 where in dielectric composition x is 0.
Claim 5
Dependent Claim 14 words
A capacitor according to claim 2 where in the dielectric composition x is 0.
Claim 6
Dependent Claim 14 words
A capacitor according to claim 1 where in the dielectric composition x is 0.01-0.08.
Claim 7
Dependent Claim 14 words
A capacitor according to claim 2 where in the dielectric composition x is 0.01-0.08.
Claim 8
Dependent Claim 12 words
A capacitor according to claim 1 wherein the metal electrodes are Pd/Ag.
Claim 9
Dependent Claim 28 words
A capacitor according to claim 1 having a dielectric constant of at least 4000 exhibiting a change in capacitance of about 1% or less per decade in hours.
Claim 10
Dependent Claim 28 words
A capacitor according to claim 2 having a dielectric constant of at least 4000 exhibiting a change in capacitance of about 1% or less per decade in hours.
Claim 11
Dependent Claim 25 words
A capacitor according to claim 7 wherein the Pd/Ag electrodes contain no more than 20% Pd based upon the total weight of palladium and silver.

References Cited (Backward Citations)

US2919483A Cited
US3472777A Cited
FR2130903A5 Cited
US3757177A Cited
US3809973A Cited
US3909327A Cited
US4048546A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-10-14 1984-04-14 1984-10-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-10-14 1988-04-14 1988-10-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-10-14 1992-04-14 1992-10-14 $7700.00 Window Closed / Lapsed

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