| 摘要 |
PURPOSE:To manufacture easily, in a good reproducible manner, a thermal head and to reduce remarkably power consumption by decreasing the thermal conductivity and thermal capacity of a heat insulating layer of the thermal head, by a method wherein the heat insulating layer of a substrate for the thermal head is produced as follows: make particulates of an insulating material aggregate in layers on a ceramic substrate, and make only a surface of the particulates reflow; thereafter, solidify it. CONSTITUTION:SiO2 fines of 100Angstrom in spherical diameter are dispersed in water. A water content in this colution is vaporized to a viscosity of 20000 poise and an aggregate of the SiO2 fines is obtained on an alumina substrate printed in a band state under a heating element 3 on the alumina ceramic substrate 1. When baked in the air after printing, surfaces of SiO2 particles are softened keeping their spherical forms as they are, to be adhered to one another and be simultaneously sticked fast to a surface of the alumina substrate. Since this glaze layer has holes of about 100Angstrom on the surface, when it is dipped into water it gradually unpreferably absorbs water. Then, in order to avoid that, a non-porous SiO2 layer of 1mu in thickness is formed on the surface by sputtering SiO2. |
