| abstract |
1431462 Etching AGFA-GEVAERT AG 2 Nov 1973 [3 Nov 1972] 50947/73 Heading B6J Relief images are formed in a polymer layer by spraying on to selected areas of the layer using an ink jet printer a substance which itself alters the solubility of the layer with respect to a given solvent or contributes to the alteration in solubility, and then treating the layer overall with said given solvent. The polymer layer may be dissolved sufficiently to reveal an underlying metal layer, e.g. a copper layer, which is then etched, e.g. in Fe-111 chloride solution. The polymer layer may be protein (e.g. gelatin), polyvinyl alcohol, copolymers with vinyl alcohol units, cyclo-rubber, alkyd resins of polyvalent alcohols and acids, polymers which contain N- methylol-ether groups, or phenol formaldehyde resin. The substance sprayed on by the ink jet printer may be a chromate, an aluminium or zirconium salt, an aldehyde, e.g. a glycol aldehyde, glyoxal, a glutaric aldehyde, or an acrolein croton aldehyde, an acid which contains an aldehyde group, an a or a γ-diketone, a hydroxyketone, an ethylene imine or ethylene oxide derivative, tisacrylaylhexahydrotriazine, organic azides, carbonyl azides, sulphonyl azides, hydrazones, 5-membered hererocyclic rings which contain nitrogen, mercapto compounds, pyritium or thiopyritium salts, thiooxanthrones, dye-Redox systems, acridines or phenothiazines, laphines, α-phenyl-ethyl alcohols, polynuclear quinones, anthraquinone-2- carboxylic acid butyl esters, phenanthrene quinones, benzophenone derivatives, benzoin, benzoin ether; hydroxymethylbenzoin, trypsin, biolase, bioprase, quinone diazides or p-toluene sulphonic acid. The solvent which is applied overall to the polymer layer may be water, aqueous alkali or methyl ethyl ketone. |