BARIUM TITANATE SEMICONDUCTIVE CERAMIC AND ITS PRODUCTION

PURPOSE:To diversify a specific resistance-temperature characteristics of a laminated thick-film sintered material of fibrous or flaky barium titanate crystal particles by forming a laminate while dividing the direction of the crystal axis in at least two directions and baking the laminate. CONSTITUTION:A fibrous semiconductive barium titanate powder is produced by mixing 2TiO2.H2O and Ba(OH)2.8H2O at equimolar ratio, adding 0.1-0.4mol% of a semiconductor-forming agent [e.g. Y(NO3).6H2O] to the mixture and subjecting to hydrothermal synthesis. The obtained powder is mixed with a solvent and an organic binder, etc., the formed slurry S is charged into a slurry tank 2 of a doctor blade apparatus and an endless carrier film 4 is circulated at a definite speed. The slurry S is discharged through the gap between the doctor blades 6a, 6b and the film 4 to form a crystal-oriented thick film 8 having a thickness of 10-100mum on the film 4. The thick films 8 are laminated while directing the crystal axis in two directions and the obtained laminate 16 is hot-pressed in the direction of thickness, degreased at about 500 deg.C and baked at about 1300 deg.C.