| 摘要 |
PURPOSE:To maintain production of gaseous ammonia from a closed vessel constant, by providing a closed vessel furnished with a porous film impermeable to water but permeable by ammonia and water vapor, in a developing chamber. CONSTITUTION:An aqueous ammonia is supplied into a developing drum 1 and stays here. The ammonia and water vapor pass through the through holes of a punches metal drum 11 and and a porus film 12 out of the developing drum 1. The film 12 has a feature that its critical surface tension (dyne/cm) is smaller than the surface tension of water. Photosensitive papers conveyed with a belt circulating in the developing chamber 1 come into contact with the ammonia and the water vapor and they are developed. When the ammonia concentration becomes dilute during development, an ammonia concentration detector 3 sends a signal to a controller 7, a heater 6 is actuated by this signal, and accordingly, an amount of gasses, especially ammonia produced passing through the film 12 is maintained constant. |
