← Back to Patent Explorer
US4948767A Expired / Lapsed US ⏱️ 0.0 years remaining

Ferroelectric ceramic material

Assignee: Mitsui Chemicals Inc
•
Filing: 1989-05-24
•
Granted: 1990-08-14
•
Expires: 2009-05-24
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The present invention relates to a ferroelectric ceramic material which is a Perovskite solid solution comprising a solid solution represented by the formula: Pb.sub.1-a M.sub.a (Mg.sub.1/3 p0 Nb.sub.2/3).sub.x Ti.sub.y Zr.sub.z O 3 containing in the solution at least one oxide selected from the group A noted below and at least one oxide selected from the group B noted below. Group A : La 2 O 3 and Nd 2 O 3 ; Group B : ZnO, SnO 2 and Ta 2 O 5 . The proposed ferroelectric ceramic material has a large piezoelectric strain constant d. The present invention is further directed to ferroelectric ceramic which is a Perovskite solid solution comprising a solid solution represented by the formula: Pb.sub.1 -aM.sub.a (Mg.sub.1/3 Nb.sub.2/3).sub.x Ti.sub.y Zr.sub.z O.sub.3 wherein M is Ba or Sr, x+y+z is 1, a is from 0 to 0.10, x is from 0.05 to 0.70, y is from 0.25 to 0.50 and z is from 0.05 to 0.70, containing in the solution at least one oxide selected from the group A noted below and at least one oxide selected from the group B noted below, the solid solution further containing in the solid solution MnO 2 . Group A : La 2 O 3 and Nd 2 O 3 ; Group B : ZnO and SnO 2 .

Inventors

  • 👤 Yoshihisa Ushida
  • 👤 Nobuki Hirai
  • 👤 Hiroshi Mase

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 09:53
CPC Classifications
H; H10; H10N; H10N30/00; H10N30/80; H10N30/85; H10N30/853; C; C04; C04B; C04B35/00; C04B35/01; C04B35/48; C04B35/49; C04B35/491; C04B35/493

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 200 words
A ferroelectric ceramic material which is a Perovskite solid solution, which comprises a solid solution represented by the formula: Pb.sub.1-a M.sub.a (Mg.sub.1/3 Nb.sub.2/3).sub.x Ti.sub.y Zr.sub.z O.sub.3 wherein M is Ba or Sr, x+y+z is 1, a is from 0 to 0.10, x is from 0.05 to 0.70, y is from 0.25 to 0.50 and z is from 0.05 to 0.70, containing in said solution at least one oxide selected from group A noted below and at least one oxide selected from group B noted below: Group A: La 2 O 3 and Nd 2 O 3 ; Group B: ZnO, SnO 2 and Ta 2 O 5 wherein the metal ions of the oxide selected from group B are present in the Perovskite solid solution in such an amount so that the relation: 0.5≦N≦5.0 is met, in which N is defined by the equation: ##EQU5## wherein n Ai and n Bj are valencies of metal ions of the oxides of groups A and B which are present in the solid solution, respectively, and x Ai and x Bj are atom equivalents of metal ions of the oxides of groups A and B which are present in the solid solution, respectively.
Claim 2
Dependent Claim 200 words
A ferroelectric ceramic material which is a Perovskite solid solution, which comprises a solid solution represented by the formula: Pb.sub.1-a M.sub.a (Mg.sub.1/3 Nb.sub.2/3).sub.x Ti.sub.y Zr.sub.z O.sub.3 wherein M is Ba or Sr, x+y+z is 1, a is from 0 to 0.10, x is from 0.05 to 0.70, y is from 0.25 to 0.50 and z is from 0.05 to 0.70, containing in said solution at least one oxide selected from group A noted below and at least one oxide selected from group B noted below: Group A: La 2 O 3 and Nd 2 O 3 ; Group B: ZnO, SnO 2 and Ta 2 O 5 wherein the metal ions of the oxide selected from group B are present in the Perovskite solid solution in such an amount so that the relation: 0.5≦N≦5.0 is met, in which N is defined by the equation: ##EQU5## wherein n Ai and n Bj are valencies of metal ions of the oxides of groups A and B which are present in the solid solution, respectively, and x Ai and x Bj are atom equivalents of metal ions of the oxides of groups A and B which are present in the solid solution, respectively.
Claim 3
Dependent Claim 37 words
The ferroelectric ceramic material of claim 1, wherein a metal of at least one oxide selected from the group A is present in the Perovskite solid solution in the form of La 3+ or Nd 3+ .
Claim 4
Dependent Claim 54 words
The ferroelectric ceramic material of claim 2 wherein the metal ions of the oxide selected from the group A are present in the Perovskite solid solution in an amount of from 0.5 to 5.0 atom equivalents based on 100 atom equivalents of the sum of Pb and M present in the Perovskite solid solution.
Claim 5
Dependent Claim 38 words
The ferroelectric ceramic material of claim 1, wherein a metal of the oxide selected from the group B is present in the Perovskite solid solution in the form of Zn 2+ , Sn 4+ or Ta 5+ .
Claim 6
Dependent Claim 209 words
A ferroelectric ceramic material which is a Perovskite solid solution, which comprises a solid solution represented by the formula: Pb.sub.1-a M.sub.a (Mg.sub.1/3 Nb.sub.2/3).sub.x Ti.sub.y Zr.sub.z O.sub.3 wherein M is Ba or Sr, x+y+z is 1, a is from 0 to 0.10, x is from 0.05 to 0.70, y is from 0.25 to 0.50 and z is from 0.05 to 0.70, containing in said solution at least one oxide selected from group A noted below and at least one oxide selected from group B noted below, said solution further containing in said solid solution M n O 2 : Group A: La 2 O 3 and Nd 2 O 3 ; Group B: ZnO and SnO 2 wherein the metal ion of the oxide selected from group B is present in the Perovskite solid solution in such an amount so that the relation: 0.5≦N≦5.0 is met, in which N is defined by the equation: ##EQU6## wherein n Ai and n Bj are valencies of metal ions of the oxides of groups A and B which are present in the solid solution, respectively, and x Ai and x Bj are atom equivalents of metal ions of the oxides of groups A and B which are present in the solid solution, respectively.
Claim 7
Dependent Claim 209 words
A ferroelectric ceramic material which is a Perovskite solid solution, which comprises a solid solution represented by the formula: Pb.sub.1-a M.sub.a (Mg.sub.1/3 Nb.sub.2/3).sub.x Ti.sub.y Zr.sub.z O.sub.3 wherein M is Ba or Sr, x+y+z is 1, a is from 0 to 0.10, x is from 0.05 to 0.70, y is from 0.25 to 0.50 and z is from 0.05 to 0.70, containing in said solution at least one oxide selected from group A noted below and at least one oxide selected from group B noted below, said solution further containing in said solid solution M n O 2 : Group A: La 2 O 3 and Nd 2 O 3 ; Group B: ZnO and SnO 2 wherein the metal ion of the oxide selected from group B is present in the Perovskite solid solution in such an amount so that the relation: 0.5≦N≦5.0 is met, in which N is defined by the equation: ##EQU6## wherein n Ai and n Bj are valencies of metal ions of the oxides of groups A and B which are present in the solid solution, respectively, and x Ai and x Bj are atom equivalents of metal ions of the oxides of groups A and B which are present in the solid solution, respectively.
Claim 8
Dependent Claim 35 words
The ferroelectric ceramic material of claim 5, wherein a metal of the oxide selected from the group A is present in the Perovskite solid solution in the form of La 3+ or Nd 3+ .
Claim 9
Dependent Claim 54 words
The ferroelectric ceramic material of claim 6, wherein the metal ion of the oxide selected from the group A is present in the Perovskite solid solution in an amount of from 0.5 to 5.0 atom equivalents based on 100 atom equivalents of the sum of Pb and M present in the Perovskite solid solution.
Claim 10
Dependent Claim 35 words
The ferroelectric ceramic material of claim 5, wherein a metal of the oxide selected from the group B is present in the Perovskite solid solution in the form of Zn 2+ or Sn 4+ .
Claim 11
Dependent Claim 29 words
The ferroelectric ceramic material in accordance with claim 6 wherein the MnO 2 is present in the solid solution in an amount of from 0.1 to 2.0% by weight.
Claim 12
Dependent Claim 39 words
The ferroelectric ceramic material of claim 1, wherein metal ions of oxides of group A and metal ions of oxides of group B are incorporated into A sites and B sites of an ABO 3 type Perovskite crystal, respectively.
Claim 13
Dependent Claim 39 words
The ferroelectric ceramic material of claim 5, wherein metal ions of oxides of group A and metal ions of oxides of group B are incorporated into A sites and B sites of an ABO 3 type Perovskite crystal, respectively.
Claim 14
Dependent Claim 33 words
The ferroelectric ceramic material of claim 5, wherein a is from 0.01 to 0.07, x is from 0.10 to 0.60, y is from 0.30 to 0.45, and z is from 0.10 to 0.60.
Claim 15
Dependent Claim 33 words
The ferroelectric ceramic material of claim 5, wherein a is from 0.01 to 0.07, x is from 0.10 to 0.60, y is from 0.30 to 0.45, and z is from 0.10 to 0.60.

References Cited (Backward Citations)

US3268453A Cited
US3956150A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-08-13 1994-02-12 1994-08-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-08-13 1998-02-12 1998-08-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-08-13 2002-02-12 2002-08-14 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag