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US4450240A Expired / Lapsed US ⏱️ 0.0 years remaining

Ceramic compositions having high dielectric constant and high specific resistivity

Assignee: NEC Corp
•
Filing: 1983-03-15
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Granted: 1984-05-22
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Expires: 2003-03-15
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Abstract

Abstract The ceramic composition comprises lead magnesium tungstate [Pb(Mg1/2 W1/2)O3], lead titanate [PbTiO3] and lead nickel niobate [Pb(Ni1/3 Nb2/3)O3]. When the ternary composition is expressed by [Pb(Mg1/2 W1/2)O3]x [PbTiO3]y [Pb(Ni1/3Nb2/3)O3]z where x+y+z=1.00, it lies on lines interconnecting five points (x=0.693, y=0.297, z=0.01), (x=0.495, y=0.495, z=0.01), (x=0.195, y=0.465, z=0.35), (x=0.10, y=0.40, z=0.50) and (x=0.06, y=0.24, z=0.70) and in a region bonded by the lines. In modifications, for the purpose of improving the mechanical strength, 0.02 to 3 mol % of at least one auxiliary ingredient selected from the group consisting of Nb, Ta and Sb, 0.05 to 8 mol % of [Pb(Mn1/3 Ta2/3)O3] 0.05 to 10 mol % of [Pb(Mn1/3 Nb2/3)O3] or 0.05 to 6 mol % of [Pb(Mn1/3 Sb2/3)O3] is added.

Inventors

  • 👤 Haruhiko Miyamoto
  • 👤 Masatomo Yonezawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 21:25
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/018; H01G4/06; H01G4/08; H01G4/12; H01G4/1209; H01G4/1254; C; C04; C04B; C04B35/00; C04B35/01; C04B35/495; C04B35/497; C04B35/499; H01G4/1218

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 92 words
A ceramic composition consisting essentially of lead magnesium tungstate [Pb(Mg 1/2 W 1/2 )O 3 ], lead titanate [PbTiO 3 ] and lead nickel niobate [Pb(Ni 1/3 Nb 2/3 )O 3 ] wherein the composition is expressed by [Pb(Mg 1/2 W 1/2 )O 3 ] x [PbTiO 3 ] y [Pb(Ni 1/3 Nb 2/3 )O 3 ] z where x+y+z+1.00, said composition lies on lines interconnecting five points (x=0.693, y=0.297, z=0.01) (x=0.495, y=0.495, z=0.01), (x=0.195, y=0.455, z=0.35), (x=0.10, y=0.40, z=0.50) and (x=0.06, y=0.24, z=0.70) and in a region bounded by said lines.
Claim 2
Dependent Claim 92 words
A ceramic composition consisting essentially of lead magnesium tungstate [Pb(Mg 1/2 W 1/2 )O 3 ], lead titanate [PbTiO 3 ] and lead nickel niobate [Pb(Ni 1/3 Nb 2/3 )O 3 ] wherein the composition is expressed by [Pb(Mg 1/2 W 1/2 )O 3 ] x [PbTiO 3 ] y [Pb(Ni 1/3 Nb 2/3 )O 3 ] z where x+y+z+1.00, said composition lies on lines interconnecting five points (x=0.693, y=0.297, z=0.01) (x=0.495, y=0.495, z=0.01), (x=0.195, y=0.455, z=0.35), (x=0.10, y=0.40, z=0.50) and (x=0.06, y=0.24, z=0.70) and in a region bounded by said lines.
Claim 3
Dependent Claim 31 words
The ceramic composition according to claim 1 which further comprises 0.02 to 3 atomic % of at least one auxiliary ingredient selected from the group consisting of Nb, Ta and Sb.
Claim 4
Dependent Claim 23 words
The ceramic composition according to claim 1 which further comprises 0.05 to 8 mol % of [Pb(Mn 1/3 Ta 2/3 )O 3 ].
Claim 5
Dependent Claim 23 words
The ceramic composition according to claim 1 which further comprises 0.05 to 10 mol % of [Pb(Mn 1/3 Nb 2/3 )O 3 ].
Claim 6
Dependent Claim 23 words
The ceramic composition according to claim 1 which further comprises 0.05 to 6 mol % of [Pb(Mn 1/3 Sb 2/3 )O 3 ].
Claim 7
Dependent Claim 20 words
The ceramic composition according to claim 1 wherein said composition is sintered at a temperature of 900° to 1050° C.

References Cited (Backward Citations)

US4048546A Cited
JPS55111011A Cited
JPS55144609A Cited
JPS55144610A Cited
JPS55144612A Cited
JPS55144611A Cited
JPS55144470A Cited
US4379319A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-05-22 1987-11-21 1988-05-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-05-22 1991-11-21 1992-05-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-05-22 1995-11-21 1996-05-22 $7700.00 Window Closed / Lapsed

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