A flameproof sheet contains a flameproof material and an elastic member, and the flameproof material is laminated with the elastic member so that a joint surface of the flameproof material with the elastic member and a joint surface of the elastic member with the flameproof material are movable along the joint surface.

An endless belt includes a base material layer, the base material layer containing a polymer material and conductive particles, wherein in a section of the base material layer in a thickness direction, the conductive particles have an area ratio of 9.0% or more and 14.5% or less, an average value of areas of Delaunay triangles taking centers of gravity of the conductive particles as vertices is 0.10 m.sup.2 or more and 0.90 m.sup.2 or less, and a standard deviation of the areas is 0.010 m.sup.2 or more and 0.080 m.sup.2 or less.