Fixing device
A tubular fuser device 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 includes a tubular substrate made of a metal, a rubber layer covering the outer periphery of the substrate, an adhesion layer covering the outer periphery of the rubber layer, and a surface layer made of a resin covering the outer periphery of the adhesion layer. The adhesion layer has a first adhesion layer that is in contact with the rubber layer and a second adhesion layer interposed between the first adhesion layer and the surface layer. The first adhesion layer is made of a fluororesin-based adhesive, and the second adhesion layer is made of a silicone rubber-based adhesive containing an ionic conductor.
1. 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,
the adhesion layer having a first adhesion layer that is in contact with the rubber layer and a second adhesion layer interposed between the first adhesion layer and the surface layer, wherein
the first adhesion layer is made of a fluororesin-based adhesive, and the second adhesion layer is made of a silicone rubber-based adhesive containing an ionic conductor.
2. The fuser device according to claim 1 , wherein a charge decay ΔV at a moment 120 seconds after end of charging a surface of the surface layer to −1 kV is equal to or less than 30 V, wherein a dielectric relaxation time T of the fuser device is equal to or less than 10 msec, and wherein a ratio Ct/AΔV of an electrostatic capacity per unit area C/A 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 is equal to or greater than 1.04×10 −18 F/Vμm.