Film for use in fixing device and fixing device with film

A fixing device for fixing a toner image onto a recording material, the fixing device comprising:

• (A) a cylindrical film contacting the recording material, the film includes
• (a) a base layer having a cylindrical shape;
• (b) an electrical conductive layer formed on the base layer and having a cylindrical shape, wherein a volume resistivity of the electrical conductive layer is lower than that of the base layer, wherein the electrical conductive layer includes,
• a first end part provided at an end of the electrical conductive layer in a longitudinal direction of the film,
• a second end part provided at an opposite end in relation to the first end part in the longitudinal direction of the film, and
• a middle part provided between the first end part and the second end part in the longitudinal direction of the film, wherein the middle part includes a plurality of slits arranged in a circumferential direction of the electrical conductive layer;
• and
• (B) a power supply members being in contact with the first and second end parts of the film, and configured to supply power to the middle part via the first and second end parts,
• wherein the toner image is fixed onto the recording material by heat of the film, and
• wherein a thickness of each of the first and second end parts is larger than that of the middle part.