Fuser device

A tubular fuser device that rotates and is in contact with a sheet on which a positively charged toner image is formed to fix the toner image to the sheet, the fuser device comprising:

• a tubular substrate made of a metal,
• a rubber layer covering an outer periphery of the substrate,
• an adhesion layer covering an outer periphery of the rubber layer, and
• a surface layer made of a resin covering an outer periphery of the adhesion layer, a charge decay ΔV at a moment 120 seconds after end of charging a surface of the surface layer to −1 kV being greater than zero, a ratio Ct/ΔV of an electrostatic capacity per unit area C in a thickness direction of the fuser device to a value ΔV/t obtained by dividing the charge decay ΔV by a thickness t of the fuser device being equal to or less than 3.13×109 pF/Vμm.