Abstract: A dielectric ceramic composition is disclosed which includes: a main ceramic composition of barium oxide and titanium oxide, or barium oxide, titanium oxide and at least one of strontium oxide, calcium oxide, zirconia and zinc oxide, which composition is represented by (1-a-b)BaO.aSrO.bCaO.x[(1-c)TiO.sub.2.cZrO.sub.2 ].yZnO, where 3.1.ltoreq.x.ltoreq.5.4, 0.ltoreq.y.ltoreq.2.9, 0.ltoreq.a+b.ltoreq.0.4, 0.ltoreq.c.ltoreq.0.2; and a secondary component at least a part of which consists of a B.sub.2 O.sub.3 material or a glass material containing as one of glass components, the secondary component being added to the main ceramic composition, in an amount of 0.1-7.5 parts by weight of B.sub.2 O.sub.3 per 100 parts by weight of the main ceramic composition.

Abstract: Disclosed is a BaO-xTiO.sub.2 dielectric ceramic composition (x=3.5 to 4.5) containing BaTi.sub.4 O.sub.9 and Ba.sub.2 Ti.sub.9 O.sub.20, wherein the content ratio of Ba.sub.2 Ti.sub.9 O.sub.20 {Ba.sub.2 Ti.sub.9 O.sub.20 /(BaTi.sub.4 O.sub.9 +Ba.sub.2 Ti.sub.9 O.sub.20)}obtained by a X-ray diffraction maximum peak height integration method described below is less than 0.19,content ratio of Ba.sub.2 Ti.sub.9 O.sub.20 ={a peak height ascribed to the (421) face of Ba.sub.2 Ti.sub.9 O.sub.20 +a peak height ascribed to the (222) face thereof}/[{a peak height ascribed to the (200, 140) face of BaTi.sub.4 O.sub.9 +a peak height ascribed to the (121) face thereof+a peak height ascribed to the (230, 150) face thereof}+{a peak height ascribed to the (421) face of Ba.sub.2 Ti.sub.9 O.sub.20 +a peak height ascribed to the (222) face thereof}].In the above dielectric ceramic composition, it is possible to prevent the occurrence of hexagonal pattern cracks and hence to improve the yield.

Abstract: The present invention is directed to non-reducible dielectric composition consisting essentially of a main composition composed of a modified barium titanate system and additives (A) and (B) incorporated therein, said main composition consisting essentially of oxides of Ba, Ca, Ti, Zr, and Nb and having a composition represented by general formula:{(Ba.sub.1-x Ca.sub.x)O}.sub.m (Ti.sub.1-o-p Zr.sub.o Nb.sub.p)O.sub.2+p/2'wherein x, o, p and m satisfy the relationships of, ##EQU1## said additive (A) being composed at least one oxides selected from the group consisting of oxides of Mn, Fe, Cr, Co, and Ni, said additive (A) being incorporated into said main composition in an amount of 0.02 to 2.0 moles per 100 moles of said main composition in terms of respective oxides, MnO.sub.2, FeO.sub.3, Cr.sub.2 O.sub.3, CoO, and NiO, said additive (B) consisting of SiO.sub.2 and/or ZnO and incorporated into said main composition in an amount of 0.1 to 2.0 moles per 100 moles of said main composition.

Abstract: A method of sintering a ceramic material composed of alkaline earth metal titanate and mixtures thereof, wherein the ceramic material is mixed with a sintering aid of a mixture of a mixed metal oxide of the formula BaCuO.sub.2 and an oxide selected from the group consisting of tungsten trioxide, molybdenum trioxide and mixtures thereof, and sintering the mixture.

Abstract: Disc and monolithic (multilayer) ceramic capacitors having a fine grained barium titanate body exhibit a high dielectric constant and a smooth (X7R) temperature coefficient of capacitance. The start ceramic materials for making such capacitors are predominantly spherical barium titanate powder particles of average particle size less than 0.7 micron and of narrow particle size distribution. The barium titanate is mixed with around 2 weight percent of a the cadmium silicate flux, 3Cd.SiO.sub.2, serving as a reactivity and sintering promoting agent; and about one weight percent of a reactivity and sintering inhibitor agent, Nb.sub.2 O.sub.5. After preparing a green body of this mixture, the body is sintered at about 1100.degree. C.

Abstract: A dielectric ceramic composition represented by the compositional formula: .sub.x BaO-.sub.y TiO.sub.2 -.sub.z Nd.sub.2 O.sub.3 -.sub.t Sm.sub.2 O.sub.3 -.sub.w Bi.sub.2 O.sub.3 so composed as to be in the molar fractions of 0.06.ltoreq.x.ltoreq.0.25, 0.60.ltoreq.y.ltoreq.0.80, 0.05.ltoreq.z.ltoreq.0.18, 0<t.ltoreq.0.07 and 0<w.ltoreq.0.05, provided that x+y+z+t+w=1, and a compositional range of Y<0.68 and Z>0.15 is excluded. As an additive, at least one of Al.sub.2 O.sub.3, ZrO.sub.2, etc. may be added. Part of Ba may be replaced with at least one of Sr, Ca and Mg. The Sm.sub.2 O.sub.3 and Nd.sub.2 O.sub.3 each may have a purity of at least 70 wt. %.

Abstract: A non-reducible dielectric ceramic composition comprises of a basic composition expressed by the general formula:{(Ba.sub.1-x-y Sr.sub.x Ca.sub.y)O}.sub.m (Ti.sub.1-o-p Zr.sub.o Nb.sub.p)O.sub.2+p/2wherein 0.05.ltoreq.x 0.30, 0.005.ltoreq.y.ltoreq.0.12, 0.ltoreq.o.ltoreq.0.20, 0.0005.ltoreq.p.ltoreq.0.012, and 1.002.ltoreq.m.ltoreq.1.03, or{(Ba.sub.1-x-y-z Sr.sub.x Ca.sub.y Mg.sub.z)O}.sub.m (Ti.sub.1-o-p Zr.sub.o Nb.sub.p)O.sub.2+p/2wherein 0.05.ltoreq.x.ltoreq.0.35, 0.005.ltoreq.y 0.12, 0.0005 .ltoreq.z.ltoreq.0.05, 0<o.ltoreq.0.20, 0.0005.ltoreq.p.ltoreq.0.02, 1.000.ltoreq.m.ltoreq.1.04. The composition contains an additive (A) composed of one or more oxides selected from the group of MnO.sub.2, Fe.sub.2 O.sub.3, Cr.sub.2 O.sub.3, CoO and NiO in an amount of 0.02 to 2.0 moles per 100 moles of the basic composition. The composition further contains an additive (B) consisting of SiO.sub.2 and/or ZnO in an amount of 0.1 to 2.

Abstract: A nonreducible dielectric ceramic composition of a system, (A.sub.1-x R.sub.x).sub.y BO.sub.3, is prepared by preparing a slurry containing at least one compound selected from the group consisting of carbonates and hydroxides of Ba, Sr, Ca and Mg, at least one compound selected from the group consisting of carbonates and hydroxides of rare earth elements R, and at least one compound selected from the group consisting of oxides, carbonates and hydroxides of Ti, Zr and Sn; filtering the resulting slurry; washing the filter cake with water and calcining the resulting washed cake.

Abstract: The invention is a process to manufacture a controlled-porosity ceramic material by synthesizing an aerogel produced by hypercritical drying of a high-porosity gel.Applications in the submarine acoustic field (active and passive sonars).

Abstract: This invention concerns with microwave devices including resonant elements made from dielectric materials represented by the nominal formulas Ba.sub.2 Ti.sub.9 O.sub.20, BaTi.sub.4 O.sub.9, ZrTiO.sub.4 (Sn) and the like. The resonant element is produced conventionally by a process including numerous steps of mixing, drying, screening, calcining, ball milling, drying, screening or remilling and spray drying, forming and sintering. These steps may take 72 hours or more, prior to the forming step, and are labor and energy consuming. The improvement resides in the use of a reduced number of steps which include mixing precursor powders with addition of water and dispersants, spray drying or flocculating and drying the mixed formulation, forming and reactively sintering, so as to reduce the total processing time, prior to the forming step, to form about 8 to 24 hours.

Abstract: A barium titanate based dielectric ceramic composition having a temperature coefficient range of about +/-15% form its value at 25.degree. C. over a temperature range of -55.degree. C. to 125.degree. C., and a dielectric constant in excess of 5000, is prepared from a ternary system comprising barium titanate, nickel niobate and manganese niobate in the molar ratios of approximately 97.23 mole % of BaTiO.sub.3, 2.35 mole % of NiO.sub.(1-x).NbO.sub.2.5(x), and 0.42 mole % of MnO.sub.1-y).NbO.sub.2.5(y), where x may equal approximately 0.73 and y approximately 0.53. Tantalum is also used in place of the niobium.

Abstract: A monolithic ceramic capacitor is characterized in that dielectric ceramic layers are made up of a dielectric ceramic composition consisting essentially of a basic composition and an antireducing agent incorporated therein to prevent it from reduction. The basic composition mainly comprises barium titanate and a bismuth compound incorporated therein, and the internal electrodes comprises a copper or a copper alloy. The antireducing agent has a composition expressed by the general formula: ##EQU1## wherein RO is at least one oxide selected from the group consisting of MgO, CaO, SrO and BaO, .alpha., .beta. and .gamma. are molar percentages of the respective components and take a value within the following respective ranges, 5.ltoreq..alpha..ltoreq.20, 10.ltoreq..beta..ltoreq.60, 20.ltoreq..gamma..ltoreq.35. The internal electrode may contain at least one additive selected from the group consisting of glass frit, powered dielectric and antireducing agent.

Abstract: A composition consisting essentially of 60.0-70.0 mol % TiO.sub.2, 14.3-20.0 mol % Nd.sub.2 O.sub.3, 11.0-16.7 mol % BaO, 1.0-8.0 mol % ZrO.sub.2 and 0.05-0.30 mol % CeO.sub.2. This composition is useful for forming densified ceramic dielectric bodies having a dielectric constant of at least 65 and which meet COG specifications, and multilayer capacitors that contain such dielectric bodies.

Abstract: A low firing dielectric composition containing an admixture of finely divided particles of manganese doped-lead iron-tungsten niobate, barium titanate and optionally an inorganic sintering aid, dispersed in an organic medium. This composition is useful for forming capacitors.

Abstract: A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula(1-.alpha.){(Ba.sub.k-x M.sub.x)O.sub.k (Ti.sub.1-y R.sub.y)O.sub.2-(y/2) }+.alpha.CaZrO.sub.3where M is either or both of magnesium and zinc, R is a rare earth element or elements, and .alpha., k, x and y are numerals in specified ranges. To this major ingredient is added a minor proportion of a first additive ingredient and a second additive ingredient. The first additive ingredient is at least either of chromium oxide and aluminum oxide. The second additive ingredient is a mixture of boric oxide or lithium oxide, silicon dioxide and at least one metal oxide selected from among barium oxide, strontium oxide, calcium oxide, magnesium oxide and zinc oxide.

Abstract: A complex oxidation reaction product of two or more metals in an oxidized state is formed by positioning a suitable precursor metal adjacent to a permeable mass of a metal-containing compound in an oxidizing atmosphere and heating the assembly to form a body of molten precursor metal. The molten metal infiltrates the permeable mass and reacts therewith and with the oxidizing atmosphere to form a complex oxidation reaction product. Methods for determining the shape of the resulting article are described. The disclosed methods can be used to form superconducting perovskites.

Abstract: The present invention provides a ceramic having a first region comprising a dielectric porcelain having an insulating layer at the crystal grain boundary of a semiconductor porcelain containing 0.50 to 5.30 mol parts of MnO.sub.2 and 0.02 to 0.40 mol parts of Y.sub.2 O.sub.3 per 100 mol parts of the principal components comprising 49.50 to 54.00 mol % of TiO.sub.2 and 50.50 to 46.00 mol % of SrO, and a second region comprising a dielectric porcelain containing further 0.40 to 5.00 mol parts of MgO and 0.05 to 2.00 mol parts of SiO.sub.2 per 100 mol parts of the principal components in addition to the composition of the first region, and also provides a circuit substrate and an electronic circuit substrate using the same ceramic.

Abstract: A process for producing a high density ceramic of perovskite represented by the formula:ABO.sub.

Abstract: An improved process for preparing crystalline mixed metal oxides, such as barium titanate, in which an organometallic compound is reacted simultaneously and continuously with a solution of a divalent alkaline earth metal ion in an alkaline high turbulence energy environment, the reaction product is crystallized, and the crystals are isolated.

Abstract: A dielectric ceramic powder composition for forming multilayer ceramic devices having thin dielectric layers with low porosity and having a dissipation factor which meets or exceeds X7R specifications, and consisting essentially of an admixture of a major component ceramic powder particle and minor component additives the amounts of which are controlled within certain predetermined ratios.

Abstract: A composition for producing ceramic dielectrics which comprises: a mixture of barium titanate which has average particle size of 0.1-1.5 .mu.m is amounts of 98-60 mole % and a perovskite type barium titanate solid solution which has average particle size of 0.1-1.5 .mu.m and a Curie temperature of 50.degree.-115.degree. C. in amounts of 2-40 mole %; and(A) at least one of niobium oxides and tantalum oxides in amounts of 0.3-2 moles % in relation to 100 mole % of the mixture; and(B) at least one of cobalt oxides, nickel oxides, magnesium oxides, manganese oxides, copper oxides and oxides of a rare earth metal in amounts of 0.1-2 moles % in relation to 100 mole % of the mixture.The composition provides a ceramic dielectric which has a large relative permittivity and still has a small temperature dependence of relative permittivity within .+-.15% over a temperature range between -55.degree. C. and +125.degree. C. taking a relative permittivity at 20.degree. C. as a standard.

Abstract: Mixed metal oxide electroceramics are produced from dissolved metal oxides using aqueous processing. For example, zirconates and titanates are manufactured from titania and zirconia using aqueous processing by forming an ammonium titanium complex, or an ammonium zironium complex, which can then be further reacted to release ammonia and form a metal titane or metal zirconate precursor. The precursor is then pyrolyzed to the corresponding oxide, e.g. barium and/or strontium titanate.

Abstract: A dielectric ceramic for microwave applications is comprised of:X BaO.Y TiO.sub.2.Z {(Sm.sub.2 O.sub.3).sub.1-W1-W2 (La.sub.2 O.sub.3).sub.W1 (Nd.sub.2 O.sub.3).sub.W2 }where X, Y, Z lie in the ranges: 11.0.ltoreq.X.ltoreq.22.0; 60.0.ltoreq.Y.ltoreq.75.0; and 6.0.ltoreq.Z.ltoreq.28.0 (X+Y+Z=100) expressed in mole %, and 0<W.sub.1 .ltoreq.0.35; 0<W.sub.2 <1; and 0<(1-W.sub.1 -W.sub.2)<1; where W.sub.1, W.sub.2 and (1-W.sub.1 -W.sub.2) are mole ratios. MnO.sub.2 or Al.sub.2 O.sub.3 may also be added.Alternatively, a dielectric ceramic may comprise:X BaO.Y TiO.sub.2.Z {(Sm.sub.2 O.sub.3).sub.1-W1-W2 (La.sub.2 O.sub.3).sub.W1 (Nd.sub.2 O.sub.3).sub.W2 }.V Bi.sub.2 O.sub.3where X, Y, Z and V lie in the ranges: 11.5.ltoreq.X.ltoreq.21.0; 60.0.ltoreq.Y.ltoreq.76.0; 6.5.ltoreq.Z.ltoreq.26.0; and 0.1.ltoreq.V.ltoreq.5.0 (X+Y+Z+V=100), expressed in mole %, and 0<W.sub.1 <1; 0<W.sub.2 <1; 0.ltoreq.(1-W.sub.1 -W.sub.2)<1, where W.sub.1, W.sub.2 and (1-W.sub.1 -W.sub.2) are mole ratios. MnO.

Abstract: A ceramic body of a dielectric material on the basis of barium titanate comprises 0.2 to 0.5 atom % of antimony and/or cerium as the donor material. The grain size of the dielectric material is less than 2 .mu.m. The dielectric constant of the material exceeds 3500 and the material has a high electric resistance which is maintained at a high temperature and for a long period of time. The ceramic material is suitable for use in capacitors, in particular ultilayer capacitors.

Abstract: The ceramic sinter is composed of a metal oxide such as ZrO.sub.2 and 10-90 vol. % of metal fluoride which is selected from the group having not less than 2.5 electronegativity difference between fluoride and the metal element.The ceramic sinter has a thermal expansion coefficient of 15-20.times.10.sup.-6 /.degree.C. and is suitable for bonding with general use metals such as stainless steel to form a composite body of the ceramic sinter and the metal without causing a substantial thermal stress at the juncture thereof.

Abstract: The invention relates to a ceramic composition.It comprises at least one phase of a structure derived from that of tungsten tetragonal bronze and at least one phase of a structure derived from Perovskite.Application to the electrical and electronics industry.

Abstract: A procedure used to prepare Ba(Ti.sub.1-x),Zr.sub.x)O.sub.3 compositions wherein 0<x<0.25 having a more completely randomized distribution of Ti and Zr atoms on the TiO.sub.2 sublattice of barium titanate is described. In accordance with the present invention there is provided a method for preparing barium titanium zirconium oxide ferroelectic ceramic. The present method comprises mixing tetraalkyl titanate and alkyl zirconate in appropriate amounts to produce (Ti.sub.1-x Zr.sub.x)alkoxide wherein 0<x<0.25; reacting (Ti.sub.1-x Zr.sub.x) alkoxide wherein 0<x<0.25 to form (Ti.sub.1-x Zr.sub.x)O.sub.2 wherein 0<x<0.25 admixing (Ti.sub.1-x Zr.sub.x)O.sub.2 with BaCO.sub.3, said BaCO.sub.3 being added in a molar ratio greater than 1 relative to (Ti.sub.1-x Zr.sub.x)O.sub.2 ; heating the admixture for a period of time and at a temperature sufficient to produce Ba(Ti.sub.1-x Zr.sub.x)O.sub.3 wherein 0<x<0.25.

Abstract: The invention relates to new ceramic electrostrictive compositions having superior electrical properties, a process for the preparation of the new electrostrictive compositions and applications for the new compositions. Specifically, a solid solution composition of lead magnesium niobate-lead titanate - (barium titanate or stronium titanate) has exhibited desirable electrostrictive properties. This composition shows a diminished dependence of dielectric constant on temperature.

Abstract: Iron is used as a dopant in barium titanate semiconductor ceramic material to increase the positive temperature coefficient of resistance thereof. By the use of about 0.010 to 0.500 weight percent silica and about 0.0075 to 0.0190 weight percent iron, room temperature resisitivity can be kept adequately low while the temperature coefficient of resistance is significantly increased.

Abstract: This invention relates to new ceramic electrostrictive compositions having superior electrical properties, a process for the preparation of the new electrostrictive compositions and applications for the new compositions. Specifically, a solid solution composition of lead magnesium niobate-lead titanate--(barium titanate or stronium titanate) has exhibited desirable electrostrictive properties. This composition shows a diminished dependence of dielectric constant on temperature.

Abstract: The disclosure concerns the fabrication, by chemical process, of a ceramic material belonging to the system:Ba.sub.x Sr.sub.1-x (Ti.sub.u Zr.sub.v Hf.sub.w)O.sub.3The fabrication method comprises the following steps:preparation of an alcohol solution containing at least one titanium, zirconium or hafnium alcoholate,preparation of a determined quantity of hydrated barium hydroxide and/or hydrated strontium hydroxide in solid state;under violent shaking, dissolving of the hydroxide or hydroxides in the alcohol solution, and continuing of the reaction until a paste is obtained,drying of the paste obtained.

Abstract: An improved ceramic dielectric composition for preparing multilayer ceramic structures for electronic devices and a method of enhancing the sinterability of such compositions at low firing temperatures by improving the distribution of zinc borate based sintering flux uniformly throughout the composition.

Abstract: A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula,(1-.alpha.){(Ba.sub.k-x M.sub.x)O.sub.k TiO.sub.2 }+.alpha.CaZrO.sub.3where M is either or both of magnesium and zinc, and .alpha., k and y are numerals in specified ranges. To this major ingredient is added a minor proportion of a mixture of lithium oxide, silicon dioxide and at least one metal oxide selected from among barium oxide, strontium oxide, calcium oxide, magnesium oxide and zinc oxide. For the fabrication of capacitors the mixture of the above major ingredient and additives in finely divided form are formed into moldings of desired shape and size, each with at least two electrodes buried therein. The moldings and electrodes are cosintered in a reductive or neutral atmosphere at temperatures of less than 1200.degree. C. and then are reheated at a lower temperature in an oxidative atmosphere.

Abstract: A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula,(1-.alpha.){(Ba.sub.k-x M.sub.x)O.sub.k TiO.sub.2 }+.alpha.CaZrO.sub.3where M is either or both of calcium and strontium, and .alpha., k and y are numerals in specified ranges. To this major ingredient is added a minor proportion of a mixture of lithium oxide, silicon dioxide and at least one metal oxide selected from among barium oxide, strontium oxide, calcium oxide, magnesium oxide and zinc oxide. For the fabrication of capacitors the mixture of the above major ingredients and additives in finely divided form are formed into moldings of desired shape and size, each with at least two electrodes buried therein. The moldings and electrodes are cosintered in a reductive or neutral atmosphere at temperatures of less than 1200.degree. C. and then are reheated at a lower temperature in an oxidative atmosphere.

Abstract: A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula,(1-.alpha.){(Ba.sub.k-x M.sub.x)O.sub.k TiO.sub.2 }+.alpha.CaZrO.sub.3where M is either or both of calcium and strontium, and .alpha., k and y are numerals in specified ranges. To this major ingredient is added a minor proportion of a mixture of boric oxide, silicon dioxide and at least one metal oxide selected from among barium oxide, strontium oxide, calcium oxide, magnesium oxide and zinc oxide. For the fabrication of capacitors the mixture of the above major ingredient and additives in finely divided form are formed into moldings of desired shape and size, each with at least two electrodes buried therein. The moldings and electrodes are cosintered in a reductive or neutral atmosphere at temperatures of less than 1200.degree. C. and then are reheated at a lower temperature in an oxidative atmosphere.

Abstract: A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula,(1-.alpha.){(Ba.sub.k-x M.sub.x)O.sub.k TiO.sub.2 }+.alpha.CaZrO.sub.3where M is either or both of magnesium and zinc, and .alpha., k and y are numerals in specified ranges. To this major ingredient is added a minor proportion of a mixture of boric oxide, silicon dioxide and at least one metal oxide selected from among barium oxide, strontium oxide, calcium oxide, magnesium oxide and zinc oxide. For the fabrication of capacitors the mixture of the above major ingredient and additives in finely divided form are formed into moldings of desired shape and size, each with at least two electrodes buried therein. The moldings and electrodes are cosintered in a reductive or neutral atmosphere at temperatures of less than 1200.degree. C. and then are reheated at a lower temperature in an oxidative atmosphere.

Abstract: A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula,(1-.alpha.)(Ba.sub.k-x-y L.sub.x M.sub.y)O.sub.k TiO.sub.2)+.alpha.CaZrO.sub.s,where L is either or both of magnesium and zinc, M is either or both of calcium and strontium, and .alpha., k, x and y are numerals in specified ranges. To this major ingredient is added a minor proportion of a mixture of lithium oxide, silicon dioxide and at least one metal oxide selected from among barium oxide, strontium oxide, calcium oxide, magnesium oxide and zinc oxide. For the fabrication of capacitors the mixture of the above major ingredient and additives in finely divided form are formed into moldings of desired shape and size, each with at least two electrodes buried therein. The moldings and electrodes are cosintered in a reductive or neutral atmosphere at temperatures of less than 1200.degree. C.

Abstract: A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula,(1-.alpha.){(Ba.sub.k-x-y L.sub.x M.sub.y)O.sub.k TiO.sub.2 }+.alpha.CaZrO.sub.3,where L is either or both of magnesium and zinc, M is either or both of calcium and strontium, and .alpha., k, x and y are numerals in specified ranges. To this major ingredient is added a minor proportion of a mixture of boric oxide, silicon dioxide and at least one metal oxide selected from among barium oxide, strontium oxide, calcium oxide, magnesium oxide and zinc oxide. For the fabrication of capacitors the mixture of the above major ingredient and additives in finely divided form are formed into moldings of desired shape and size, each with at least two electrodes buried therein. The moldings and electrodes are cosintered in a reductive or neutral atmosphere at temperatures of less than 1200.degree. C.

Abstract: A method for producing non-reducible dielectric ceramics of the kind comprising a basic composition of a three component system BaTiO.sub.3 -CaTiO.sub.3 -CaZrO.sub.3 or a four component system BaTiO.sub.3 -CaTiO.sub.3 -CaZrO.sub.3 -MgTiO.sub.3 and containing additives composed of at least manganese oxide and silicon dioxide. The method comprises the steps of separately preparing calcined powders of at least three perovskite compounds including BaTiO.sub.3, CaTiO.sub.3 and CaZrO.sub.3, mixing the calcined powders to prepare a mixture for a basic composition, adding additives composed of at least manganese oxide and silicon dioxide to the mixtures for the basic composition, and then firing the resultant mixture in a reducing atmosphere. One of the oxides, magnesium oxide, calcium oxide, strontium oxide and barium oxide is additionally incorporated into the mixture for the basic composition together with manganese oxide and silicon dioxide.

Abstract: A ceramic composition for a reduction-reoxidation type semiconductive capacitor, comprising (A) barium titanate or barium titanate and strontium titanate, (B) titanium oxide, and (C) at least one oxide selected from the group consisting of the oxides severally of La, Ce, Nb, Nd, Dy, Y, Sb, W, and Ta in a molar ratio of 100:0.01.about.15:0.01.about.10 and further comprising (D) 0.001 to 1% by weight, based on the total amount of the compounds, (A), (B), and (C), of at least one oxide selected from the group consisting of the oxides severally of Cu, Zn, Al, Mg, and Mo and exhibiting a breakdown voltage of not less than 900 V, and insulation resistance of not less than 10.sup.10 .OMEGA., an electrostatic capacity per unit surface area of not less than 0.06 .mu.F/cm.sup.2, and a low dielectric loss, tan .delta., of not more than 2.0%.

Abstract: This invention relates to the production of ceramic materials which exhibit a dielectric constant in excess of 105, when measured at room temperature, and a small temperature coefficient of capacitance across the temperature range of -55.degree. to 125.degree. C., when compared to the capacitance measured at room temperature, which material has a composition encompassed within one of the following general formulae:(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m O.sub.3m+1).sup.2- ; (I)(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m Zr.sub..beta. O.sub.3m+.delta.+1).sup.2- ; and (II)(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m Mn.sub..gamma. O.sub.3m+.delta.+1).sup.2- (III)(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m Zr.sub..beta. Mn.sub..gamma. O.sub.3m+.delta.+1).sup.

Abstract: The present invention provides a dielectric ceramic composition for use in a high-frequency range represented by the general formula (1-x)Ba.sub.1- y(Zn.sub.1/3, Ta.sub.2/3)O.sub.3 +xBa.sub.1-y ZrO.sub.3. In the formula, y is 0.004.ltoreq.y.ltoreq.0.013 and x is the amount of substitution of Ba.sub.1-y ZrO.sub.3 and 0<x.ltoreq.0.06. This composition is prepared by weighing raw materials so that the mixing ratio of Ba is slightly smaller than that of the stoichiometric composition, calcining the resultant mixture to prepare a calcination product, grinding the calcination product through only dry process without conducting wet pulverization, molding the resultant powder, and sintering the molded product at 1600.degree. to 1700.degree. C. for 1 to 10 hr.

Abstract: A dielectric material for use in a microwave resonator comprises 78.1 mol % of TiO.sub.2, 15.7 to 17.8 mol % of BaO, 4.00 ml % of SnO.sub.2 and at least one of 0.1 to 1.0 mol % of SrO and 0.1 to 1.2 mol % of CaO.

Abstract: A process for preparing a tetragonal barium titanate film with a thickness of from about 0.1 to about 1.5 millimeters is disclosed.In the first step of this process, a mixture of a barium compound, a titanium compound, and a boron oxide glass former is provided in a specified ratio.The reaction mixture is melted at a temperature of 1300-1400 degrees centigrade and then rapidly quenched in form glass. The glass is then place upon a polycrystalline isostructural substrate, and the glass/substrate assembly is then remelted and, thereafter, subjected to a temperature of from 950 to 1,050 degrees centigrade for from about 25 to about 60 minutes.

Abstract: A complex oxidation reaction product of two or more metals in an oxidized state is formed by positioning a suitable precursor metal adjacent to a permeable mass of a metal-containing compound in an oxidizing atmosphere and heating the assembly to form a body of molten precursor metal. The molten metal infiltrates the permeable mass and reacts therewith and with the oxidizing atmosphere to form a complex oxidation reaction product. Methods for determining the shape of the resulting article are described. The disclosed methods can be used to form superconducting perovskites.

Abstract: A positive temperature coefficient semiconductor ceramic is prepared by adding from 0.2 to 12 mole % of silicon monoxide to a barium titanate family semiconductor ceramic which has been made into a semiconductor by the addition of a trace amount of a semiconductor agent.

Abstract: Methods of producing ABO.sub.3 compounds in which A represents a first metal ion and B represents a second metal ion from mixed metal coordination complexes are disclosed. The methods involve reacting compounds serving as a source of the B metal ion with a substituted aromatic compound, in solution, and thereafter reacting the metal coordination complex formed with a compound serving as a source of the A metal, in solution. An example is the reaction of titanium tetraisopropoxide with catechol to form a titanium catecholate coordination complex which is thereafter reacted with barium hydroxide octahydrate to form a pentamethanol barium triscatecholatotitanate mixed metal coordination complex which can be calcined at elevated temperatures to produce the ABO.sub.3 compound, barium titanate (BaTiO.sub.3), which is known to have outstanding dielectric, ferroelectric and piezoelectric properties. Portions of the A and/or B ions can be substituted with other metals.

Abstract: The present invention provides ceramic compositions for preparing multi-layer capacitors, having high dielectric constants between about 4900 and 5400, dissipation factors below about 2.0%, high insulation resistance capacitance products and stable temperature coefficient characteristics, by a process of mixing a major oxide component with one or more precipitated dopant components.

Abstract: The invention concerns a process for preparing titanates and zirconates respectively of formulas MTiO.sub.3 and MZrO.sub.3 where M is Ba.sup.2+, Sr.sup.2+, Ca.sup.2+, Pb.sup.2+ and Mg.sup.2+ to the exclusion of MgZro.sub.3, consisting of reacting an ester of formula M[H-(CH.sub.2).sub.n CO.sub.2 ].sub.2 where n=1-4 with the formula M'[O(CH.sub.2).sub.n CH.sub.2).sub.n CH.sub.3 ].sub.4 where M' is Ti or Zr bringing the reaction mixture to boil until the solvent is removed to yield a viscous translucent resin. The resin is cooled and further treated to obtain the desired product.

Abstract: A ceramic dielectric composition useful in the manufacture of compact ceramic capacitors consisting essentially of barium titanate and zirconium dioxide has a dielectric constant ranging from 1800 to 3500 and a heat dissipation factor, tangent delta, less than 3% over the operating temperature range of electronic circuit components.