Abstract: A positive temperature coefficient thermistor formed of a principal ingredient comprising barium titanate, lead titanate and calcium titanate, and rare earth elements, being particularly characterized by using calcium titanate as a raw material and having the particle diameter of said calcium titanate among raw material powders made smaller than that of other raw materials. The positive temperature coefficient thermistor formed by the present invention has improved durability in a reducing atmosphere due an increased density of the crystal structure.

Abstract: A temperature sensor includes a thermistor in a heat-resistant cap and lead wires electrically connected to the thermistor. The thermistor is comprised of materials defined by the following chemical formula:(Al.sub.1-x-y Cr.sub.x Fe.sub.y).sub.2 O.sub.3wherein 0.05.ltoreq.x+y.ltoreq.0.95, and 0.05.ltoreq.y/(x+y).ltoreq.0.6. The thermistor may also include CaO, rare earth oxide, ThO.sub.2 or ZrO.sub.2. The thermistor has an excellent long term resistance stability, which is important in high temperature applications of the temperature sensor, such as measurement of automobile catalytic converters temperature.

Abstract: The present invention relates to oxide semiconductors for thermistors for use as sensors mainly in a temperature range of 200.degree.-500.degree., an embodiment of which comprises 5 kinds of metal elements 60.0-98.5 atomic % of Mn, 0.1-5.0 atomic % of Ni, 0.3-5.0 atomic % of Cr, 0.2-5.0 atomic % of Y and 0.5-28.0 atomic % of Zr, to the sum total of 100 atomic %; the oxide semiconductors for thermistors have an excellent characteristic feature as temperature sensors for use in intermediate and high temperature ranges; that is, giving such a small resistance change with time as within .+-.5% at temperatures between 200.degree.-500.degree. C., they are most suitable for temperature measurement applications where high reliability is required at high temperatures.

Abstract: This invention relates to an oxide semiconductor for a thermistor to be used as a sensor mostly in the temperature range of 200.degree. C.-700.degree. C. The semiconductor contains four metal elements, that is, Mn in an amount 65.0-98.5 atom %, Ni in an amount of 0.1-5.0 atom %, Cr in an amount of 0.3-5.0 atom % and Zr in an amount of 0.05-25.0 atom %, the total of the four elements being 100 atom %. This oxide semiconductor for a thermistor has outstanding feature for use as a temperature sensor in the medium to high temperature ranges in that the change of resistance with time at temperatures of 200.degree. C.-700.degree. C. is confined within .+-.5%, and thus the semiconductor of this invention is most suited for high-temperature determinations where high reliability is required.

Abstract: In a ceramic dielectric composition with BaTiO.sub.3 as host material, CaTiO.sub.3 and Sb.sub.2 O.sub.3 are added to be contained, and besides thereto any one of Nd.sub.2 O.sub.3, La.sub.2 O.sub.3 and Sm.sub.2 O.sub.3 are added to be included, thereby ceramic dielectric composition having high dielectric constant, small voltage dependency of characteristics, large bending force, and small equivalent series resistance in high frequency range is provided.Also, by having BaTiO.sub.3 as host material and adding CaTiO.sub.3 and Ta.sub.2 O.sub.5 thereto, and further adding Sb.sub.2 O.sub.3 or Pr.sub.6 O.sub.11, similar superior characteristics to the above-mentioned ceramic high dielectric composition is obtainable.Besides, by adding SiO.sub.2 to the above-mentioned ceramic high dielectric compositions, strength is further increased.These ceramic dielectric composition of high dielectric constant is suitable for, for example, dielectric substance of laminated ceramic capacitor.

Abstract: Oxide thermistor compositions which comprise 100 atomic % of at least four kinds of cations which are (1) Mn ion, (2) Ni ion, (3) at least one kind of ion selected from the group consisting of Cu, Fe, and Cr, and (4) one kind of ion selected from the group consisting of Cr, Zr, and Li. These compositions have lower resistivity with higher B-constant and exhibit a high stability of resistance.