Abstract: A method and apparatus for producing characters on a surface of a grit-erodible body are provided. A negative of the characters is first produced, usually photographically. Ultraviolet light is then directed through the negative onto a blasting mask blank comprising a backing sheet and a uniform layer of polymerizable material thereon. Light struck portions of the layer harden and the rest is washed away to produce the characters, and specifically a font of type. Selected characters are then positioned backward on a transfer sheet and transported to the surface of the body of grit-erodible material to which they are adhered, with the transfer sheet then peeled away. Blasting grit is then directed toward the surface to erode the grit-erodible material around the characters to a desired depth.

Abstract: A punch for a cutting die is provided for forming holes in corrugated board or the like. The hole punch includes a tubular metal member of circular transverse cross section having one end substantially flush with the back surface of a die plate in which it is mounted and the other end extending beyond the front surface of the die plate and terminating in a circular cutting edge. A body of resilient material, preferably molded rubber, is located within the cylindrical member and has one end terminating near the back end of the tubular member and another end terminating near the cutting edge of the tubular member. The purpose of the body is to eject and strip the scrap of corrugated board from the punch and from the rest of the blank being formed by the cutting die. The resilient body has a central, cylindrical recess at one end which enables the resilient material to be deformed inwardly when engaging a corrugated board being cut by the circular cutting edge.

Abstract: A punch for a cutting die is provided for forming holes in corrugated board or the like. The hole punch includes a tubular metal member of circular transverse cross section having one end substantially flush with the back surface of a die plate in which it is mounted and the other end extending beyond the front surface of the die plate and terminating in a circular cutting edge. A body of resilient material, such as natural gum rubber or latex, is located within the cylindrical member and has one end terminating near the back end of the tubular member and another end terminating near the cutting edge of the tubular member. The purpose of the body is to eject and strip the scrap of corrugated board from the punch and from the rest of the blank being formed by the cutting die. The resilient body has a central, cylindrical passage extending completely therethrough, in a preferred form.

Abstract: Apparatus for printing indicia on corrugated board in particular is provided. The apparatus includes a printing plate made of a polymer material which has a number of advantages over conventional printing plate materials. However, because the polymer material is somewhat resilient and exhibits a degree of yieldability, and dimensionally-stable sheet is provided, which is either on the back of the material or molded into the material near the back. The printing plate is adhered to a mounting sheet which is also dimensionally stable and is mounted on a printing plate cylinder. A resilient or compressible layer or pad is affixed to the back of the mounting sheet, between the mounting sheet and the printing cylinder, and is of a size at least equal to that of the printing plate.

Abstract: Mounting means for mounting a printing plate on a printing plate cylinder are provided. The mounting means include a mounting member or sheet made of a plastic sheet material which is solvent resistant, strong, dimensionally stable, conforms truly to the printing plate cylinder, and is of uniform thickness. The leading edge of the mounting member is turned back to form a structurally-integral lip thereon which is readily connected to a mounting flange on the printing plate cylinder. The mounting means further include a mounting strap which affixes the mounting member on the cylinder with the lip engaged with the flange of the cylinder. The mounting strap has a first portion received in an opening of the mounting member and a second portion having an integral lip which engages another mounting flange of the printing cylinder.