THERMAL HEAD

PURPOSE:To remove common irregularity by relaxing heat accumulation by enabling heat insulation to be realized to an extent that heat interference between heating elements can be neglected by a method wherein a groove for heat insulation is provided to a glazed glass layer between the adjacent heating elements and outside the heating elements of left and right both end parts. CONSTITUTION:A groove 20 is provided between mutual glazed glass layers 16 existing under each heating element 12 of an individual electrode 14 and further a groove 20a is provided to a mid way between an individual electrode 14a existing at left and right both ends and the glazed glass layer 16 existing under an extended part 13a of a common electrode 13 existing at left and right both ends. A width of the grooves 20 and 20a is as broad as possible within a gap of the individual electrodes 14 placed in an array, and its length is made slightly longer than a length L of a heating part of the heating element 12.