Patent ID: 8916799

Claim:
A flat electric heater element, comprising: a carrier film; two current conductor layers arranged on a first face of the carrier film at a distance from each other; an electrical resistance layer arranged on the first face, extending between the two current conductor layers and being in electrically conductive contact with the two current conductor layers, wherein an electric current is flowable through the electrical resistance layer between the current conductor layers; an adhesive layer including electrically insulating material and disposed over the electrical resistance layer and the current conductor layers, wherein the adhesive layer has a self-adhesive surface for adhesively bonding the flat electric heater element to an element to be heated, and the element to be heated includes thermally conductive material; and at least one passage opening, the carrier film, the current conductor layers and the electrical resistance layer extending around the passage opening, wherein the carrier film has at least one relatively wide region and at least one relatively narrow region adjacent to the at least one relatively wide region along an edge of the passage opening, the at least one relatively wide region of the carrier film carries more electrical resistance material of the electrical resistance layer than the at least one relatively narrow region for generating more heating energy than the at least one relatively wide region, and the carrier film, the two current conductor layers, and the electrical resistance layer are all present in the at least one relatively wide region and in the at least relatively narrow region along the edge of the passage opening.