PURPOSE: To obtain a rubber roll which has a covering rubber layer having a smooth outer surface, undergoing little change with time, and improved in coefficient of friction, strengths, and durability by compounding a rubber mixture with a vegetable powder.

CONSTITUTION: A rubber roll material is obtd. by compounding 100 pts.wt. rubber mixture mainly comprising a high-acrylonitrile butadiene rubber with 5-20 pts.wt. vegetable powder having a particle size of 15-200 mesh and a reinforcing filler comprising carbon and silica. The material is used to cover a metal core and vulcanized to give a rubber roll which is used for conveying metal plates (e.g. iron, copper, or nonferrous metal plates) in a metal-plate- treating line. Thus, metal plates can be conveyed without damaging their surfaces.