Method of making hand proofs of color prints

Claim 1

A hand proof process for making colored prints, said process comprising the steps of: (a) placing a substrate in a fixed position on a machine; (b) applying a first coloring material to said substrate, said coloring material comprising a single color including powdered printer's ink pigment mixed with an ink-like carrier; (c) rubbing talcum powder on the first coloring material after said first coloring material has dried; (d) applying a non-transparent photosensitizer over said first coloring material after said talcum powder has been rubbed on said first coloring material, said photosensitizer being water soluble and comprising a pigmented polyvinyl alcohol sensitized with a sensitizer selected from the group consisting of bichromate and diazo salts; (e) exposing said photosensitizer to light through a photographic mask; (f) removing the portions of the photosensitizer which are not exposed to light; (g) removing the portions of the first coloring material which are no longer protected by the photosensitizer; (h) removing the remaining photosensitizer with a fluid that does not affect the first coloring material, said fluid comprising a solvent which does not have any affect upon the pigmented resins used in the ink, whereby said first coloring material is uncovered by photosensitizer; (i) applying an isolation layer over the remaining first coloring material, said isolation layer comprising a clear and transparent layer of lacquer; (j) applying a second coloring material over said isolation layer after said isolation layer has dried, said second coloring material comprising a single color including powdered printer's ink pigment mixed with an ink-like carrier; (k) rubbing talcum powder on said second coloring material after said second coloring material has dried; (l) applying a non-transparent photosensitizer over said second coloring material after said talcum powder has been rubbed on said second coloring material, said photosensitizer being water soluble and comprising pigmented polyvinyl alcohol sensitized with a sensitizer selected from the group consisting of bichromate and diazo salts; (m) exposing said photosensitizer to light through a photographic mask; (n) removing the portions of said photosensitizer which are not exposed to light; (o) removing the portions of said second coloring material which are not protected by the photosensitizer; and (p) removing the remaining photosensitizer with a fluid that does not affect the second coloring material, whereby said first and second coloring materials remaining after the removal of the photosensitizer are not covered by any photosensitizer.