US 4,812,426 AGranted

Lead-containing oxide powder

AssigneeDenki Kagaku Kogyo Kabushiki Kaisha

InventorsTouichi Takagi, Kohei Ametani, Kouichi Shimizu

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Abstract

According to the invention a powder of lead-containing oxides and a process for preparing the same for the production of an element for electrical and other applications are provided. The powder is prepared by mixing and calcining a powder of oxides of metals other than lead, lead-containing oxides, metal substances forming the oxides upon calcination or mixtures thereof, adding and mixing a powder of a lead substance to obtain a mixture and then calcining the mixture. The powder includes a Perovskite type lead-containing oxides of the formula of ABO.sub.3 wherein A is a metal element coordinated with 12 oxygen atoms and containing at least lead, and B is a metal element coordinated with 6 oxygen atoms. A phase containing the lead forms a skin layer of the powder.

Claims30

Dependent claims

A process for preparing a powder of lead-containing oxides for the production of an element comprising the steps of:

(a) mixing and calcining a powder of a material selected from the group consisting of titanium oxide, lead-containing titanium oxide, metal substances forming said titanium oxide upon calcination and mixtures thereof with or without a powder of a material selected from the group consisting of oxides of metals other than lead, lead-containing metal oxides,metal substances forming said oxides upon calcination and mixtures thereof, the metal constituting said oxides of metals other than lead being selected from the group consisting of zirconium (Zr), lithium (Li), copper (Cu), magnesium (Mg), nickel (Ni), barium (Ba), calcium (Ca), strontium (Sr), zinc (Zn), manganese (Mn), cobalt (Co), tin (Sn), iron (Fe), cadmium (Cd), antimony (Sb), aluminum (Al), rare earth metals, indium (In), selenium (Se), niobium (Nb), tantalum (Ta), bismuth (Bi), tungsten (W), tellurium (Te), rhenium (Re) and mixtures thereof, said metal substances forming said oxides upon calcination being selected from the group consisting of elemental metals, metal carbonates, metal oxalates, metal formates, metal hydroxides and basic metal carbonates;
(b) adding and mixing a powder of a lead substance to obtain a mixture, said lead substance being selected from the group consisting of PbO, Pb.sub.3 O.sub.4, PbO.sub.2, Pb, (PbCO.sub.3).sub.2.Pb(OH).sub.2, PbCO.sub.3, Pb(CH.sub.3 COO).sub.4, Pb(CH.sub.3 COO).sub.2.Pb(OH).sub.2 and mixtures thereof;
and
(c) calcining said mixture at a temperature of from 400.degree. C. to 1200.degree. C.

1 more element

A powder of lead-containing oxides for the production of an element comprising a lead oxide and an oxide of at least one metal other than lead, said powder being prepared by mixing and calcining a powder of a material selected from the group consisting of titanium oxide, lead-containing titanium oxide, metal substances forming said titanium oxide upon calcination and mixtures thereof with or without a powder of a material selected from the group consisting of oxides of metals other than lead, lead-containing metal oxides, metal substances forming said oxides upon calcination and mixtures thereof, the metal constituting said oxides of metals other than lead being selected from the group consisting of zirconium (Zr), lithium (Li), copper (Cu), magnesium (Mg), nickel (Ni), barium (Ba), calcium (Ca), strontium (Sr), zinc (Zn), manganese (Mn), cobalt (Co), tin (Sn), iron (Fe), cadmium (Cd), antimony (Sb), aluminum (Al), rare earth metals, indium (In), selenium (Se), niobium (Nb), tantalum (Ta), bismuth (Bi), tungsten (W), tellurium (Te), rhenium (Re) and mixtures thereof, said metal substances forming said oxides upon calcination being selected from the group consisting of elemental metals, metal carbonates, metal oxalates, metal formates, metal hydroxides and basic metal carbonates;

adding and mixing a powder of a lead substance to obtain a mixture, said lead substance being selected from the group consisting of PbO, Pb.sub.3 O.sub.4, PbO.sub.2, Pb, (PbCO.sub.3).sub.2.Pb(OH).sub.2, (Pb(CH.sub.3 COO).sub.4, Pb(CH.sub.3 COO).sub.2.Pb(OH).sub.2 and mixtures thereof;
and then calcining the mixture.

Dependencies are inferred from the claim text.

Facts

Application: 07/012,103Filed 6 Feb 1987 · continuation in part
Priority: JP 59-17242521 Aug 1984
Granted: 14 Mar 1989
Term ends: Not estimatedThe source records don’t support an estimate.

Classification23 codes

H01B 1/08
Mainly consisting of other non-metallic substances: oxides
C01B 13/185
By thermal decomposition of compounds, e.g. of salts or hydroxides: preparing mixtures of oxides
C01G 21/22
Compounds of lead: plumbates; Plumbites
C01G 25/006
Compounds of zirconium: compounds containing zirconium, with or without oxygen or hydrogen, and containing two or more other elements