GB1362979A - Process for the manufacture of a make-ready foil for relief printing - Google Patents

Abstract

1362979 Photo-polymerizable processes producing relief images BADISCHE ANILIN-& SODA-FABRIK A G 10 Dec 1971 [12 Dec 1970] 57435/71 Heading G2C Relief images are produced by imagewise exposing through the support a material comprising (a) an actinic-light transmissive, dimensionally stable support, (b) an intermediate, non-photo-polymerizable layer 5-60 microns thick containing 0À01-10 wt. per cent of the total weight of layer (b) of actinic-light absorbing compounds and (c) a photo-polymerizable layer 20-250 microns thick also containing 0À01-10 wt. per cent of the total weight of layer (c) of actinic-light absorbing compounds, and developing to remove the unexposed areas of (c) and the underlying areas of (b). The lightabsorbing compound may be a metal-complex dye (e.g. as in Specification 1287216) or a conventional U.V. absorber (e.g. hydroxybenzophenones, bisphenol, di- or tri-nitrophenols). The photo-polymerizable composition of layer (c) is preferably a polyamide, an acrylic monomer, a photo-initiator and a polymerization inhibitor. Layer (b) is preferably the same as layer (c) without the photo-initiator and possibly the monomer. The relief image varies in height and is substantially proportional to the total values of the original except that 0-30% of the light is absorbed by layer (b) and thus the darker parts of the original are not reproduced. The binder for layer (c) may be a vinyl or an acrylic polymer, a cellulose, a polyester or polyether instead of the preferred polyamide.