| 摘要 |
<p>Process discloses partial hot-air drying of photographic films after coating the carrier. An aq. colloidal layer compsn. having viscosity >8 cps. and contg. 5-15 wt. % water-permeable hydrophilic colloid, is applied to carrier. At least 20% water is removed from applied layer in 10 secs., by blowing air onto surface at 93-121 degrees C, measured by dry bulb thermometer, and 29-43 degrees C, measured by wet bulb thermometer. Air flows at 37-55 m3/min. per m2 of layer. Treatment is suitable for photographic emulsions on X-ray, lithographic-, orthochromatic-, panchromatic and infra-red films, esp. emulsions contg. a photosensitive Ag halide and gelatine. Hot air flow velocity is sufficient to remove water quickly, but low enough to prevent running. Partial drying obviates need for cooling coated strip. Gelatine crystallisation is prevented. Fog is reduced. Shorter, cheaper driers can be used.</p> |
