摘要 |
<p>In a ceramic heater, a resistive heating element formed from a ceramic electrically conductive material is embedded in a ceramic body. The ceramic electrically conductive material has a structure in which particles of an electrically conductive ceramic phase are dispersed in a matrix ceramic phase, and contains the ceramic electrically conductive phase in a range of from 30 to 80 % by weight. When a virtual circle is drawn with a certain radius in a section of said ceramic electrically conductive material, if the percentage of the area of said electrically conductive ceramic phase particles in the virtual circle is not smaller than 60 %, a region enclosed by the circle is defined as an uneven distribution portion of said electrically conductive ceramic phase particles and the maximum diameter of the uneven distribution portion is set to be not larger than 5 mu m. <IMAGE></p> |