| 摘要 |
<p>PURPOSE:To eliminate the drawback that the maximum usable temperature is low without deteriorating a glazed substrate by sandwitching a low alkali glass layer between the glazed substrate and an exothermic resistor. CONSTITUTION:A low alkali glass layer 7, which has a thickness of 0.2 to 50 microns and a softening temperature higher than 745 deg.C and which contains the sum of Na2O + K2O in a quantity lower than 1.0 wt.% is applied by the high frequency sputtering process to a glazed ceramic substrate 1 which is composed of a substance having a low heat conductivity such as Al2O3 and a glass layer having a low softening point. There are further formed thereon an exothermic resistor 2 such as ZrB2, leading conductors 3 and 4 of Ti or Au, and protecting films 5 and 6 of SiO2 and Ta2O5. As a result, the thermal head thus prepared can endure its use at a high temperature and can usefully increase the thermally recording speed.</p> |
