Method of making a sleeve for a printing cylinder

A method of forming a cylindrical sleeve for a printing cylinder, comprising the steps of providing a temporary, rigid, cylindrical support which comprises an inflatable bag, wrapping a porous, slightly compressible material about said bag, disposing a thin-walled cylindrical screen about said material, said screen defining a pattern of interconnected channels extending to the lateral edges of said bag, applying a sheet of elastomeric composition which is hardenable under the influence of radiation about said screen, said sheet comprising a photopolymer, applying a vacuum to said channels for removing any accumulated gases between the outer surface of said bag and said sheet, and thereafter subjecting said sheet to a heat treatment for securing said screen and sheet together by curing, the heat treatment being carried out after removing said screen and said sheet from said bag.

A method of forming a cylindrical sleeve for a printing cylinder, comprising the steps of disposing a thin-walled cylindrical screen about the outer surface of a temporary, rigid, cylindrical support, said screen defining a pattern of interconnected channels extending to the lateral edges of said surface, applying a sheet of elastomeric composition which is hardenable under the influence of radiation about said screen, said sheet comprising a photopolymer, applying a vacuum to said channels for removing any accumulated gases between the outer surface of said support and said sheet, and thereafter subjecting said sheet to a heat treatment for securing said screen and said sheet together by curing, said heat treatment being carried out in three phases:

• first at a temperature of about 140.degree. C. for 20 to 120 min., followed by a brief cooling at room temperature for 5 to 10 min., and finally an aftertreatment at a temperature of about 140.degree. C. for 5 to 60 min.

A method of forming a cylindrical sleeve for a printing cylinder, comprising the steps of disposing a thin-walled cylindrical screen about the outer suface of a temporary, rigid, cylindrical support, said screen defining a pattern of interconnected channels extending to the lateral edges of said surface, applying a sheet of elastomeric composition which is hardenable under the influence of radiation about said screen, said sheet comprising a photopolymer, applying a vacuum to said channels for removing any accumulated gases between the outer surface of said support and said sheet, and subjecting said sheet to a heat treatment for securing said screen and sheet together by curing, the heat treatment being carried out after removing said screen and said sheet from said support, and thereafter closely fitting said secured together screen and sheet after the heat treatment about a cylindrical core member, and providing a pattern on the outer surface of said sheet using a radiation process.