| 摘要 |
<p>A porcelain insulator including a porcelain insulator main body and a coating layer formed on a surface of the porcelain insulator main body, the coating layer being made of porcelain raw materials including mainly materials of high dielectric constant and having a relative dielectric constant larger than 4, wherein a ration between maximum value and minimum value of relative dielectric constants at micro portions in the coating layer along a thickness direction of the coating layer is smaller than 2. The porcelain insulator mentioned above can be manufactured by the steps of; (1) preparing said porcelain insulator main body; (2) preparing coating materials as a slurry by (a) grinding raw materials and mixing a clay therein to prepare porcelain raw materials made of 50-60 wt% of SiO2, 20-30 wt% of Al2O3 and a remainder of MgO, CaO, K2O, Na2O, (b) preparing materials of high dielectric constant having a relative dielectric constant larger than 10 separately; and (c) mixing 100 parts by weight of the thus prepared porcelain raw materials and 3-10 parts by weight of the thus prepared materials of high dielectric constant; (3) applying the thus prepared coating materials on a surface of the porcelain main body; and (4) firing the porcelain main body in which the coating materials are applied on its surface. <IMAGE></p> |
