Method of manufacturing an external electrically conducting metal pattern

In the method of manufacturing an external electrically conducting metal pattern on a hydrophobic support which is at least superficially non-conducting, which method comprises subjecting to actinic radiation desired areas of a photosensitive coating adhering to said support and containing uniformly dispersed in an organic binder selected from the group consisting of polyesters and epoxy resins a photosensitive material selected from the group consisting of diazosulfides and diazosulfonates, and capable, upon exposure to acinic light, of producing a light reaction product which in the presence of water is capable of forming free silver and mercury metal from water-soluble silver and mercurous compounds to thereby form light reaction products at exposed areas of said coating, exposing said coating to treatment with at least one water-soluble salt selected from the group consisting of a water-soluble mercury salt and a water soluble silver salt in the presence of water to thereby form a latent metal image and then physically developing said latent metal image by treatment with an aqueous solution of a metal salt and a reducing agent for said metal salt, the improvement wherein at least in the step wherein the coating is exposed to treatment with at least one water-soluble salt in the presence of water to form a latent image in place of water there is employed a mixture of water and at least one water-soluble liquid organic solvent for said photosensitive material selected from the group consisting of chloroform, toluene, ethylacetate, liquid alcohols and liquid ketones in a ratio by volume of the total amount of organic solvent to water of 1:10 to 2:1 and wherein said mixture is capable of swelling said binder.