Ceramic heater for toner-fixing units and method for manufacturing the heater

摘要

A ceramic heater (1) that is used in a toner-fixing system comprising a ceramic heater (1) and a heat-resistant film (3), that reduces the degree of deformation of the heat-resistant film (3), that lightens the load applied to the film at the time of revolution, that prevents the fracture of the film, and that enables fixing at a high rate exceeding 24 paper sheets per minute. A ceramic base material (11) of the ceramic heater (1) attached to a heating cylinder (2) comprises aluminium nitride or silicon nitride. A heating element (12) and current-feeding electrodes are made of silver or silver alloy and are formed on the ceramic base material (11). In the ceramice heater (1) at least one part of the face (the fixing face) that contacts the heat-resistant film (3) is curved when viewed from a direction perpendicular to the feeding direction of a copying sheet.