| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a spark plug wherein the glost firing in which residues of bubbles or the like are difficult to be generated can be carried out relatively at low-temperatures, and wherein a glaze layer of superior anti-chipping property is obtained in its turn. SOLUTION: After plural glaze compositions in which the softening points and the coefficients of linear expansion respectively differ are melted by component source powders to become respective component sources of respective glazes, these are pulverized and plural kinds of constituent glaze powders are manufactured. Then, these constituent glaze powders are mixed to compose a prepared glaze powder, and by coating it on an insulator and by making the glost firing, the glaze layer is obtained. |
