METHOD OF MANUFACTURING SPARK PLUG

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing a spark plug capable of easily obtaining the spark plug excellent in flush over resistance by effectively avoiding uneven glazing on the surface of insulator body by increasing in viscosity of glaze slurry. SOLUTION: The slurry is prepared by suspending glaze powder into a water based solvent using coated glaze powder, the surface of which is previously coated with an elution suppressing coating layer which suppresses elution of an aqueous ingredient from the glaze. The slurry deposits a glaze powder deposition on the surface of insulator body. The graze layer is formed by firing the glaze powder deposition.