Heater, fixing apparatus, and image forming apparatus

A fixing apparatus comprising:

• a substrate;
• at least one heat generation resistance element that is provided on the substrate and that extends in a longitudinal direction of the substrate;
• a power supply electrode that is provided on the substrate and that is configured to supply electric current to the at least one heat generation resistance element;
• an auxiliary layer that is provided to superpose only a partial region of the at least one heat generation resistance element and that has insulation property;
• and
• a protection layer that is layered on the auxiliary layer and provided to cover a whole region of the at least one heat generation resistance element and that is configured to protect the at least one heat generation resistance element;
• a first rotating body configured to be heated by the heat generation resistance element;
• and
• a second rotating body configured to form, together with a fixing film, a nip portion,
• wherein the fixing apparatus is configured to fix a toner image formed on a recording material by heat.

An image forming apparatus comprising:

• an image forming unit configured to form a toner image on a recording material;
• and
• a fixing apparatus
• wherein the fixing apparatus comprises:
• a substrate;
• at least one heat generation resistance element that is provided on the substrate and that extends in a longitudinal direction of the substrate;
• a power supply electrode that is provided on the substrate and that is configured to supply electric current to the at least one heat generation resistance element;
• an auxiliary layer that is provided to superpose only a partial region of the at least one heat generation resistance element and that has insulation property;
• and
• a protection layer that is layered on the auxiliary layer and provided to cover a whole region of the at least one heat generation resistance element and that is configured to protect the at least one heat generation resistance element;
• a first rotating body configured to be heated by the heat generation resistance element;
• and
• a second rotating body configured to form, together with a fixing film, a nip portion,
• wherein the fixing apparatus is configured to fix a toner image formed by the image forming unit.