Image heating apparatus, pressure roller to be used in the image heating apparatus, and manufacturing method for the pressure roller

{
  "publication_number": "US2011217092A1",
  "country": "US",
  "kind": "A1",
  "title": "Image heating apparatus, pressure roller to be used in the image heating apparatus, and manufacturing method for the pressure roller",
  "abstract": "The image heating apparatus includes a rubber layer and a resin tube layer on a metal core. The rubber layer includes a solid rubber layer having a thermal conductivity in a thickness direction of 0.16 W/(m·K) or more and 0.40 W/(m·K) or less, and a self-bonded silicone rubber layer that contains a filler of 5 vol % or more and 40 vol % or less, and has a thermal conductivity in an axial direction of 2.5 W/(m·K) or more and a thickness of 0.5 mm or more and 5.0 mm or less, the filler having a length of 0.05 mm or more and 1 mm or less and a thermal conductivity in a length direction of 500 W/(m·K) or more, so that a pressure roller to moderate temperature rise in a non-sheet feeding area when a small sized recording material has undergone sheet feeding can be easily manufactured.",
  "claims": [
    "1. An image heating apparatus for heating a toner image formed on a-recording material, comprising: a heat member for heating the toner image formed on the recording material; and a pressure roller comprising a metal core, a rubber layer, and a resin tube layer serving as a surface layer, the pressure roller forming, in cooperation with the heat member, a nip portion at which the recording material is pinched and conveyed, wherein: the rubber layer comprises a solid rubber layer having a thermal conductivity of 0.16 W/m·K or more and 0.40 W/m·K or less in a thickness direction of said solid rubber layer, and a self-bonded silicone rubber layer provided between the solid rubber layer and the resin tube layer, the self-bonded silicone rubber layer having a thickness of 0.5 mm or more and 5.0 mm or less; and the self-bonded silicone rubber layer contains needle-shaped fillers at 5 vol % or more and 40 vol % or less, and has a thermal conductivity of 2.5 W/m·K or more in an axial direction of the pressure roller, the needle-shaped fillers having an average length of 0.05 mm or more and 1 mm or less and a thermal conductivity of 500 W/m·K or more in an axial direction of the needle-shaped filler. 2. An image heating apparatus according to claim 1, wherein the needle-shaped filler is pitch-based carbon fiber. 3. An image heating apparatus according to claim 1, wherein: the heat member comprises an endless belt and a heater brought into contact with an inner surface of the endless belt; and the nip portion is formed by the heater and the pressure roller while the endless belt is interposed in the nip portion. 4. A pressure roller to be used in an image heating apparatus for heating a toner image formed on a recording material, comprising: a metal core; a rubber layer; and a resin tube layer serving as a surface layer, wherein: the rubber layer comprises a solid rubber layer having a thermal conductivity of 0.16 W/m·K or more and 0.40 W/m·K or less in a thickness direction of the solid rubber layer, and a self-bonded silicone rubber layer provided between the solid rubber layer and the resin tube layer, the self-bonded silicone rubber layer having a thickness of 0.5 mm or more and 5.0 mm or less; and the self-bonded silicone rubber layer contains needle-shaped fillers at 5 vol % or more and 40 vol % or less, and has a thermal conductivity of 2.5 W/m·K or more in an axial direction of the pressure roller, the needle-shaped fillers having an average length of 0.05 mm or more and 1 mm or less and a thermal conductivity of 500 W/m·K or more in an axial direction of the needle-shaped filler. 5. A pressure roller according to claim 4, wherein the needle-shaped filler is pitch-based carbon fiber. 6. A manufacturing method for a pressure roller to be used in an image heating apparatus, the pressure roller comprising: a metal core; a resin tube layer serving as a surface layer; a solid rubber layer having a thermal conductivity of 0.16 W/m·K or more and 0.40 W/m·K or less in a thickness direction of the solid rubber layer; and a self-bonded silicone rubber layer provided between the solid rubber layer and the resin tube layer, the self-bonded silicone rubber layer contains needle-shaped fillers at 5 vol % or more and 40 vol % or less, and has a thermal conductivity of 2.5 W/m·K or more in an axial direction of the pressure roller, the needle-shaped fillers having an average length of 0.05 mm or more and 1 mm or less and a thermal conductivity of 500 W/m·K or more in an axial direction of the needle-shaped filler, the manufacturing method comprising: placing the metal core provided with the solid rubber layer at a center of a molding die having a cylindrical inner surface; placing the resin tube layer on the inner surface of the molding die; injecting liquid addition type silicone rubber containing an adhesion-imparting agent and the needle-shaped fillers between the resin tube layer and the metal core provided with the solid rubber layer; and hardening the liquid addition type silicone rubber and bonding the resin tube layer and the liquid addition type silicone rubber together by an action of the adhesion-imparting agent. 7. A manufacturing method for a pressure roller according to claim 6, wherein the needle-shaped filler is pitch-based carbon fiber."
  ],
  "cpc": [
    "G03G 15/2057",
    "G03G 2215/2035"
  ],
  "assignees": [
    "CANON KK"
  ],
  "filing_date": "2009-12-24",
  "publication_date": "2011-09-08",
  "priority_date": "2008-12-24",
  "application_number": "US-200913128534-A",
  "family_id": "42287911",
  "citations": [
    "US2005214044A1",
    "US2009003902A1",
    "US2009047048A1",
    "US2011082260A1",
    "US2011091252A1",
    "US5011401A",
    "US6002910A",
    "US6108906A",
    "US7193181B2",
    "US7215916B2",
    "US7242895B2",
    "US7283145B2",
    "US7305208B2",
    "US7321746B2",
    "US7366455B2",
    "US7457577B2",
    "US7469120B2",
    "US7558519B2",
    "US7734241B2",
    "US7974563B2",
    "US7979015B2"
  ]
}