Abstract
In the 1970s, in order to create better quality printed matter by using of an offset printing machine, the chief printing engineer needed high skill and sufficient experience. As the various process of the sheet offset press were automated step by step, the time limitation the role played by the operator gained importance over that of the printing artist. The history of the offset press's automation, plate materials (conventional PS plate and CTP plate) that have been used, and proofs, are all explored in this paper.
