NON-AQUEOUS SILVER-HALIDE RAPID ACCESS PHOTOGRAPHY.

Ethylene glycol and methanol are the only nonaqueous solvents found thus far in which Plus X film may be developed. Development requires very high alkalinity, and only a few of the many developing agents tried will give good contrast. The major effort was put on the ethylene glycol system. Other solvents were tried and discarded because the essential reagents were not soluble in them. A search was made for materials which would act as restrainers antifoggants and developer accelerators in the glycol system without positive results. In the same solvent only thiourea and potassium thiocyanate were found to have a clearing action on Plus X film. However, these may not be used in a monobath system. A two stage develop and fix system appears possible. No gelling agent has yet been found suitable for forming the processing layers for a glycol system. For this, over a dozen natural and synthetic polymer products have so far been investigated. Author