Production of photosensitive resin cylinders

Claim 1

A process for producing a photosensitive resin cylinder of the type including a cylinder having applied to the surface thereof a smooth and uniform thickness layer of photosensitive resin material, said process comprising: winding a photosensitive resin sheet having a thickness of from 1 to 4 mm on and around the surface of a cylinder without allowing any material overlapping of or spaces between the side edge portions of the thus wound sheet; rotating said cylinder with said wound sheet thereon while contacting the surface of said wound sheet with a roll and causing said roll to rotate against said surface, and simultaneously applying heat in a single direction from an external infrared heater to said wound sheet, thereby joining said side edge portions of said wound sheet by melting, the amount of heat thus applied being sufficient to soften said wound sheet without causing said resin material to flow; and continuing said rotation of said cylinder while cooling said wound sheet, thus forming said wound sheet into a photosensitive resin layer having a uniform thickness of from 1 to 4 mm and a smooth outer surface.