| 摘要 |
PURPOSE:To produce a shadow mask perforated with fine and precise holes and having excellent quality by corroding a mask raw material having photosensitive films retained on both main faces except a small hole forming section and a large hole forming section in two corrosion tanks with different corrosion liquid shock forces. CONSTITUTION:A shadow mask raw material 11 with photosensitive films retained on both main faces except a small hole forming section with a hole width of d3 and a large hole forming section with a hole width of d4 respectively is allowed to pass through the first corrosion tank 21 in the advance direction of an arrow 20. A corrosion liquid with a large preset shock force is sprayed through a spray nozzle 21a for corrosion in this tank 21, but since the hood of photosensitive films 12, 13 generated at this time is small, the films, 12, 13 can sufficiently withstand. Next, it is allowed to pass through the second corrosion tank 22, and a corrosion liquid with a small preset shock force is injected through a nozzle so as not to collapse the hood of the photosensitive films 12, 13 which has grown larger. Next, it is sent to a water washing tank 23 to remove the photosensitive films 12, 13 and obtain a flat shadow mask. |
