| 摘要 |
1,180,438. Photo-sensitive materials. KALLE A.G. July 6, 1967 [July 8, 1966], No.31195/67. Heading G2C. A light-sensitive material comprises a transparent polymeric support coated with an o-naphthoquinone diazide and at least two alkali-fast dyes which are opaque to ultraviolet light and soluble or dispersible in organic solvents so that the layer has a photographic density above 1. The material is exposed to an original bearing a silver image and developed with alkali to remove the exposed areas and produce a positive image which may be used as masters in photo-mechanical processes. In the examples a polyester support is coated with a layer containing one or two o-naphthoquinone diazides, two or three alkali-fast dyes and optionally polyvinyl acetate is exposed to a silver image original and developed with alkali metal silicates, phosphates or carbonates and/or ethanolamines, alkylenediamines to produce a positive image. Reference has been directed by the Comptroller to Specification 1,052,699.
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