| 摘要 |
PURPOSE:To enable to finish just as designed by a method wherein a reserved copy of a letter or a figure desired to be worked by the sandblasting method is prepared beforehand and a film enlarging or contracting it into a proper size by photographic technics is employed for the copy to finish by the sandblasting. CONSTITUTION:At first, the letter or the figure desired to be worked by the sandblasting is photographed by a photographic film to make a negative film 2. Then, photosensitive resin 5 is poured into the film 2, the film 2 is covered by a transparent film 6, a glass plate 7 is put thereon further and is pressed forcibly so as to spread the resin 5 uniformly. Next, ultraviolet rays are projected for a given period of time from a direction 8. As a result, the resin 5 is cured only at the part thereof where it received light beams. After irradiation, a transparent seal 3, a partitioning plate 4, the resin 5 and the film 6 are removed and washed by a brush with thin sodium carbonate water. In this case, the cured parts are fixed on the film 6 as the letter or the figure just as the manuscript itself and, thus, the mask can be produced. |
