Image heating apparatus and pressure roller used for image heating apparatus

A roller used for an image heating apparatus, comprising:

• a metal core;
• an elastic layer containing a thermal conductive filler whose average length is not less than 0.05 mm and not more than 1 mm, wherein a thermal conductivity (λf) of the thermal conductive filler in the longitudinal direction of the thermal conductive filler is not less than 500 W/(m·k), wherein a dispersed amount of the thermal conductive filler dispersed in the elastic layer is not less than 5 vol % and not more than 40 vol %, wherein the thermal conductivity (λy) of the elastic layer in an axial direction of the roller is not less than 2.5 W/(m·k);
• and,
• a solid rubber layer provided between the metal core and the elastic layer, wherein a thermal conductivity (λ) of the solid rubber layer in a thickness direction of the solid rubber layer is not less than 0.16 W/(m·k) and not more than 0.40 W/(m·k).

An image heating apparatus for heating an image formed on a recording material, comprising:

• a heating member that heats the image formed on the recording material;
• and
• a roller that forms a nip portion in cooperation with the heating member, wherein the recording material is conveyed in the nip portion, the roller comprising:
• a metal core;
• an elastic layer containing a thermal conductive filler whose average length is not less than 0.05 mm and not more than 1 mm, wherein a thermal conductivity (λf) of the thermal conductive filler in the longitudinal direction of the thermal conductive filler is not less than 500 W/(m·k), wherein a dispersed amount of the thermal conductive filler dispersed in the elastic layer is not less than 5 vol % and not more than 40 vol %, wherein the thermal conductivity (λy) of the elastic layer in an axial direction of the roller is not less than 2.5 W/(m·k);
• and,
• a solid rubber layer provided between the metal core and the elastic layer, wherein a thermal conductivity (λ) of the solid rubber layer in a thickness direction of the solid rubber layer is not less than 0.16 W/(m·k) and not more than 0.40 W/(m·k).

A roller used for an image heating apparatus, comprising:

• a metal core;
• an elastic layer containing a pitch-based carbon fiber, wherein a dispersed amount of the pitch-based carbon fiber dispersed in the elastic layer is not less than 5 vol % and not more than 40 vol %, wherein the thermal conductivity (λy) of the elastic layer in an axial direction of the roller is not less than 2.5 W/(m·k);
• and,
• a solid rubber layer provided between the metal core and the elastic layer, wherein a thermal conductivity (λ) of the solid rubber layer in a thickness direction of the solid rubber layer is not less than 0.16 W/(m·k) and not more than 0.40 W/(m·k).

An image heating apparatus for heating an image formed on a recording material, comprising:

• a heating member that heats the image formed on the recording material;
• and
• a roller that forms a nip portion in cooperation with the heating member, wherein the recording material is conveyed in the nip portion, the roller comprising:
• a metal core;
• an elastic layer containing a pitch-based carbon fiber, wherein a dispersed amount of the pitch-based carbon fiber dispersed in the elastic layer is not less than 5 vol % and not more than 40 vol %, wherein the thermal conductivity (λy) of the elastic layer in an axial direction of the roller is not less than 2.5 W/(m·k);
• and
• a solid rubber layer provided between the metal core and the elastic layer, wherein a thermal conductivity (λ) of the solid rubber layer in a thickness direction of the solid rubber layer is not less than 0.16 W/(m·k) and not more than 0.40 W/(m·k).