CONVECTIVE DIFFUSION OF WATER IN GELATIN LAYERS - APPLICATION OF THEORY TO PROCESS OPTIMIZATION

A review of the analytical theory of the convective diffusion of water in a swelling gelatin layer(1) is presented, together with an outline of the effect of varying hardness on times of imbibition and drying. Development time is calculated using the Danckswerts(2) method and the appropriate diffusion coefficient, assuming that developer begins to diffuse into the layer when its is fully swollen and that a constant m ass of silver is produced without significant halide loss. The total p rocessing time is then considered as a function of layer hardness.