| 摘要 |
PROBLEM TO BE SOLVED: To provide a ceramic heater which will never present any problem to the durability of a heat emitting element even if the heating/cooling cycle is repeated. SOLUTION: A ceramic heater 1 is structured so that a resistance heat- emitting element 10 consisting of a ceramic conductive material is embedded in a ceramic base body 13. The ceramic conductive material has such a structure that conductive ceramic phase particles are dispersed in the matrix ceramic phase, wherein the content of the conductive ceramic phase ranges between 30 and 80wt.%. If a virtual circle is drawn with a certain radius on one cross-section of the ceramic conductive material where the share by area of the conductive ceramic phase particles in the circle is over 60%, the region surrounded by the circle is defined as an eccentrically existing part of conductive ceramic phase particles, wherein the max. diameter of the eccentrically existing part should not exceed 5μm.
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