Details:
Summary:
SSDT, or Single Sheet Diffusion transfer, is a new litho plate developed at Howson-Algraphy for exposure by projection, either through film or from copy, or by a laser. It uses the well known technology of diffusion transfer platemaking, but in a new way. Both receptor and donor layers, normally separate sheets of aluminum and photosensitive paper in conventional DTR applications, are combined into a pre-sensitized configuration. Unlike other single sheet DTR products, which are paper or plastic based, we have used our expertise in graining and anodizing to produce a lithographic aluminum substrate. By doing this we have achieved the convenience of a single sheet product and the excellent press characteristics of anodized aluminum. Although filmless plates have been available for some years using electrostatic technology, the advantages offered by the SSDT system are simplicity of processing, low cost of equipment, and the ability to make multiple exposures. Although filmless plates have been available for some years using electrostatic technology, the advantages offered by the SSDT system are simplicity of processing, low cost of equipment, and the ability to make multiple exposures. The product described in the paper has been designed for camera exposure or for exposure by an Argon-ion laser outputting at 488 nm and has an energy requirement of approximately 10muJcm-2. It is capable of giving a resolution of up to 10mu m lines and giving press runs in excess of 50,000 impressions. We are currently involved with a number of field trials in both commercial and newspaper accounts.