Details:
Summary:
The DuPont Company recently announced plans to commercialize Dycril Photopolymer Printing Plates, a step that represents more than ten years of research and development by teams of scientists and technicians. The technical background leading to this new product is of special interest to the various craftsmen in the graphic arts. The chemistry of photopolymerization, optics of three dimensional image formation, photomechanical photography and equipment engineering are among the specialized subjects to be discussed. The Dycril plate consists of a thin layer of photo-sensitive plastic bonded to a metal support. To produce a printing relief image, a high contrast negative is placed in con- tact with the plastic surface and exposed to ultraviolet radiation. The areas shielded by opaque portions of the negative are washed away easily, leaving the exposed areas in relief. Details of each process step will be explained with emphasis on chemical and photographic aspects. Photopolymer plates have been used in all major segments of the printing industry, including dry offset and high-speed rotary wrap-around applications. Particular emphasis will be placed on press mounting and plate performance. Recent findings in the area of plate repair will also be disclosed.