| 摘要 |
<p>PURPOSE:To simplify the production process and to reduce the size of a thermal head, by applying a high resistance layer mainly composed of glass or heat- resistant resin onto the main face of an alloy mainly composed of iron and chrome, thereby eliminating process for removing wave being formed during formation of a substrate or alkali component. CONSTITUTION:A high resistance substrate 21 comprises a metal substrate 22 of Fe-Cr alloy and a high resistance layer 23 of a glass layer formed thereon and containing 16 pts. wt. of PbO, 56 pts. wt. of SiO2, 9 pts. wt. of Al2O3, 4 pts. wt. of B2O3, 8 pts. wt. of CaO and BaO, Cr2O3, NiO, for example. When a reaction layer of spinel type oxidation layer 24 is provided additionally, adhesion of the glass layer 23 can be improved. Since no ceramic substrate is employed in the high resistance substrate, a process for removing alkali metal ions which causes degradation of the function of the heating element section is not required, nor required is the surface polishing process for removing wave being produced during formation of the ceramic substrate. Although Fe-Cr series alloy contains 5-30 pts. wt. of Cr in order to exhibit corrosion resistance against production process, said alloy can serve as a common electrode conductor, thereby, the size of thermal head can be reduced.</p> |
