Abstract: In coating a substrate such as a glass plate with a photo-sensitive coating solution by spin coating, the substrate is tilted so that the coating solution flows down the substrate to cover the entire surface of the latter, and then the substrate is held horizontal, and rotated so that a layer of coating solution uniform in thickness is formed on the substrate.

Abstract: A method for forming an image comprising forming a silver, silver halide or binder image in the emulsion layer of a photographic material which comprises a support having a masking layer thereon which carries a silver halide emulsion layer, by exposing and developing the photographic material, heating the photograpic material to thermally decompose the binder of the emulsion layer, selectively removing the thermally decomposed emulsion layer at non-image areas to uncover the masking layer lying thereunder using a binder-removing solution, and then etching away the masking layer at the uncovered areas.

Abstract: A process of forming mask images having high contrast at the edges thereof and possessing high heat resistance and high durability comprising imagewise exposing a photographic light-sensitive material comprising a transparent support having thereon, in succession, a mask layer and a layer of an emulsion of a silver halide in a binder followed by development without employing fixing processing to form silver images at the image areas, removing the silver forming the silver images at the image areas with an aqueous solution containing ceric sulfate and sulfuric acid; then reducing the silver halide remaining at the non-image areas to silver; halogenating the silver formed in the non-image areas with an aqueous solution containing dichromate ions and halogen ions; heating the photographic material above about 200.degree. C.

Abstract: A process of spin coating a coating composition on the surface of a base plate, comprising supplying a material which is compatable with the coating composition, in either a liquid or vapor form, to the opposite surface of the base plate to the surface on which the coating composition has been supplied (hereinafter "back surface" or "back side") while rotating the base plate to remove the coating composition flowing to the back surface or to the edge portion of the plate. The material compatible with the coating composition may be applied to the surface of the base plate at the periphery thereof to reduce or remove the coating composition there.

Abstract: A process for effectively and rapidly desalting gelatino silver halide emulsions for photographic light sensitive elements wherein a thin film of the emulsion is formed and gelled by cooling and thereafter washed with cold water.