| 摘要 |
An improved method of making a half-tone gravure printing plate in which a planographic or relief half-tone positive and a gravure screen are printed on a photosensitive resist forming material. In the method, the lowering of the quality of printed matter resulting from formation of moire pattern can be prevented and an error caused by the reproduction step between a new half-tone positive and an original half-tone positive can be corrected. The method comprises the steps of contacting and inverting the planographic or relief half-tone positive on a soft continuous gradation film to prepare a half-tone negative, screening in a photosensitive film with screen dots of the half-tone negative eliminated by use of a contact screen to prepare a new half-tone positive; printing the new half-tone positive on a photosensitive resist forming material to form an element of sizes of dots; and forming a space between the new half-tone positive and the photosensitive resist forming material, and printing said half-tone positive, blurring the screen dots, on the photosensitive resist forming material, thereby correcting an error of gradation of a middle tone portion. |
