| 摘要 |
Light-sensitive vinyl cinnamate copolymers containing from 10 to 70 mole per cent of recurring units. -CH2-C1H-O-CO-CH = CH-R wherein R represents an aromatic monocyclic radical, e.g. phenyl, o-tolyl, o-chlorophenyl and m-nitrophenyl, and from 30 to 70 mole per cent of recurring units -CH2-C1H-O-CO-R1-COOH, wherein R1 represents a hydrocarbon residue of a diboric acid such as -CH2-, -CH2.CH2-, -CH2-CH2.CH2- or -CH = CH- or phthalic, isophthalic, terephthalic, 3-nitrophthalic, and tetrahydrophthalic acid nucleus, the polymer containing at least 70 mole per cent of said recurring units, are used to prepare photomechanical printing plates which are alkali susceptible. The remaining units may be derived from the polymerization of vinyl esters with other polymeriz, able compounds such as ethylene, vinyl chlorideketones, ethers, alkyl and acrylic acid esters. Examples mentioned are an ethylene -vinyl alcohol copolymer partially esterified with cinnamic acid chloride followed by the esterification of residual vinyl alcohol units with a dibasic acid anhydride such as succinic anhydride, or polyvinyl alcohol partly esterified with cinnamic acid halide and partly with phthalic acid anhydride. Similarly other cinnamic acid halides such as o-chlorocinnamic, m-nitrocinnamic, a -phenyl cinnamic and b -phenyl cinnamic may be used to esterify the polyvinyl alcohol. The preparation of vinyl m-nitrocinnamatevinyl succinate and phthalate copolymers and vinyl p-methoxycinnamate vinyl succinate and phthalate copolymers; vinyl cinmamate -vinyl maleate; vinyl cinnamate-vinyl 3-nitro phthalate; and vinyl cinnamate-vinyl 4-tetraphydrohthalate copolymers and an ethylene-vinyl cinnamate-vinyl hydrogen succinate terpolymer is described. Sensitizing agents such as the nitro, triphenylmethane, anthrone, quinone, ketone and thiazole compounds of the Specifications 713,947, 717,708, 717,710, 717,711, 717,712 and 743,455, may be added. Specifications 695,262, 717,709 and 813,605 also are referred to. |
