Abstract: A method for preparing a screen structure for a cathode-ray tube comprising(a) exposing a water-soluble photopolymeric film on a surface to a light image to insolubilize selected portions of the film,(b) flushing the exposed film with an aqueous medium that is free from borate ions to remove only the still-soluble portions of the film, thereby producing a stencil on the surface,(c) rinsing the stencil with an aqueous solution containing borate ions to prevent further removal of material from said stencil,(d) then overcoating the stencil and the surface not covered by the stencil with pigment particles,(e) and then removing only the stencil and the overcoating thereon.

Abstract: A method for producing etched metal bodies, particularly color television picture tube aperture masks, comprises the steps of applying a polyvinyl alcohol photoresist film to the metal substrate, exposing the film, developing the image produced by exposure, heat hardening the developed image, acid etching the metal body, heating the body to caramelize the remaining film, and stripping the caramelized film from the metal body using an aqueous caustic stripping solution. The heat caramelization step greatly enhances the caustic strippability of heat hardened polyvinyl alcohol films from metallic surfaces.