| 摘要 |
PURPOSE:To obtain high voltage resistance and stable PTC characteristics by interposing composite particles of small diameters between the same composite particles of comparatively large specific diameters imparting a PTC function. CONSTITUTION:A composite composed of BaTiO3 and Sr, Pb, Sn, Zr, etc., solved thereinto can be used as a composite for providing a PTC function. Ba1-xPbxTiO3 (x=0.5 to 0.9) easily raises the temperature and, by adjusting the composition with additions, lowers the resistance of a thermistor, therefore, is the most suitable composite. The recommended diameters and average diameter of particles of comparatively large diameters are 5mum or larger and 5-30mum respectively for improving the insulation voltage resistance and lowering the room temperature resistance value. The recommended diameters and average diameter of particles interposed between the large particles are 5mum or smaller and 0.1-4mum respectively for considerably increasing the rate of change of the resistance. Thereby a high-temperature PTC thermistor of low room temperature resistivity, a high rate of change of the resistance, and high insulation voltage resistance can be obtained. |
