| 摘要 |
PURPOSE:To obtain images capable of monochromatically discriminating different several kinds of information by printing a drawing on a photosensitive material, placing several kinds of plate screens different from each other in dot area ratio on the material in succession while using a mask material, and carrying out printing and development. CONSTITUTION:Original drawing 2 is placed on positive-positive type photosensitive material 1 such as diazo type photosensitive material, exposed with light source 5, and printed out to obtain printed-out image 3 of drawing pattern 4 of drawing 2. Plate screen 7 having 40% dot area ratio is placed on material 1, mask material 9 having mask face 6 is set on screen 7, and by exposure 40% dot printed-out image 8 is obtd. on image 3. Plate screen 10 having 60% dot area ratio is then placed, image 8 is covered with mask material 12 having mask face 11, and by exposure 60% dot printed-out image 13 is obtd. This material 1 is processed with gaseous NH3 to form a plurality of monochromatic halftone images 14 different from each other in dot size. Thus, a plurality of information about the present condition, modification, alteration, geology, etc. of a machine drawing, a map or the like is represented on one side. |
