Abstract
The report starts with the definitions and the advantages and disadvantages of offset printing with un-screened (= continuous tone) and with screened photographic originals. This is followed by the description of the historical development of screenless offset printing from the phototype or collotype process to the present art, which is characterized in that the presensitized offset printing plates known nowadays have too steep a gradation for this field of application.
First results obtained with a novel presensitized offset printing plate for screenless printing are graphically represented in the Goldberg-Jones diagram.
Notes
Paper presented at a Symposium on “Non-Silver Photonraphic Processes” organized by the Science Committee of The Royal Photographic Society. 30 September 3 October 1969 In Oxford.