Abstract: A fixing device comprises a thermal fixing roll and a pressing roll forming a nip portion together with the thermal fixing roll. The pressing roll included in the fixing device comprises a core, a sponge rubber layer covering the outer circumferential surface of the core and provided with a large number of through-holes extending in parallel with the axis of the core and arranged equidistantly from the outer circumferential surface of the core, a rubbery elastic layer formed in a thickness of 350 to 4500 .mu.m to cover the outer circumferential surface of the sponge layer, and a fluorocarbon resin layer formed to cover the outer circumferential surface of the rubbery elastic layer.

Abstract: A heat-fixing roll which includes a core shaft, and a rubber layer formed on an outer peripheral surface of the core shaft, wherein the rubber layer is formed of a silicone rubber compound of addition reaction curing type having a thermal conductivity of 1.5.times.10.sup.-3 cal/cm.multidot.sec.multidot..degree.C. or more and containing 1.5 parts by weight or more of silicone resin powder having an average particle diameter of 1 to 20 .mu.m.

Abstract: A roll having a rigid core and a non-adherent coating layer, wherein the non-adherent coating layer is obtained by obtaining a silane-modified fluororubber according to a radical addition reaction between a fluororubber (peroxide crosslinked fluororubber) including iodine and/or bromine and a silane compound having a group containing a radical reactive unsaturated bond and a hydrolytic group and then crosslinking the silane-modified fluororubber according to hydrolytic polycondensation.

Abstract: Disclosed is a fixing roll, comprising a core metal, a heat resistant elastic layer formed to cover the circumferential outer surface of the core metal, and a surface layer formed to cover the circumferential outer surface of the heat resistant elastic layer, the surface layer being formed of a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin film of a double layer structure consisting of an inner layer having a volume resistivity of 10.sup.11 .OMEGA..cm or less and an outer layer having a thickness falling within a range of between 3 .mu.m and 50 .mu.m, and the entire thickness of the resin film falling within a range of between 20 .mu.m and 500 .mu.m.

Abstract: An oil-repellent fluororubber composition obtained by compounding a low-molecular weight tetrafluoroethylene resin with a peroxide crosslinked fluororubber having a Mooney viscosity of 90 or more ML.sub.1+10 (100.degree. C.) or compounding a low-molecular weight tetrafluoroethylene resin and an inorganic filler selected from powders of solid substances, such as iron, nickel, cobalt, iron-cobalt alloy, molybdenum, tungsten, tantalum and tungsten-carbide, having surface energy higher than that of copper with a peroxide crosslinked fluororubber. An oil-repellent fluororubber elastomer having excellent oil repellency and at the same time maintaining original mechanical and physical characteristics sufficiently can be obtained, using easily available materials on the market without any special means of processing and treatment.

Abstract: A roll wherein a non-adherent coating layer comprises a peroxide crosslinked fluororubber in which a low-molecular weight ethylene tetrafluoride resin or low-molecular weight ethylene tetrafluoride and a powder of a solid element and/or an inorganic compound having surface energy higher than that of copper are compounded.

Abstract: The present invention provides a roll for a fixing unit including a sponge layer which has a multiple of through holes parallel to a longitudinal direction of a metal core and aligned in a circumferential direction of the metal core at a predetermined gap, or a through hole helically formed along the longitudinal direction of the metal core, and which is formed on a circumferential surface of the metal core, and a surface coating layer applied on a circumferential surface of the sponge layer.