Photosensitive mixt. contg. esterified copolymer of cyclic anhydride - and olefin, esterified with unsatd. alcohol, diazonium polycondensate and exposure indicator and use in printing plate prodn.

摘要

Photosensitive mixt. (I) comprises (a) a diazonium polycondensate (II), opt. mixed. with a monomeric diazonium salt (III), (b) a polymer (IV) with mw = min. 150000, obtd. by ring opening of a copolymer (V) of an intramol. anhydride (VI) of an unsatd. polybasic organic carboxylic acid and an olefin (VII) with an unsatd. alcohol (VIII) or in stages with (VIII) and a satd. alcohol (IX); and (c) exposure indicator(s) (X). Pref. (II) is a polycondensate of the 3-methoxy-diphenylamine-4-diazonium ion (IIA) with HCHO or 4,4'-bis-methoxymethyldiphenyl ether (IIB) and is pptd. as 4-tolylsulphonate or mesitylenesulphonate. (III) is a 4-tolylsulphonate or mesitylenesulphonate of a 2-methoxy-4-amino-2-substd. benzenediazonium ions; and the ratio of (II) to (III) is at least 3:1. (VI) is maleic anhydride; (VII) a substd. ethene, esp. styrene or 1-methyl-styrene; (VII) allyl alcohol, propargyl alcohol or hydroxyethyl (meth)acrylate; and (IX) n-BuOH, n-pentanol, cyclohexanol or benzyl alcohol. The molar ratio of (VIII) to (IX) is at least 3:1; and of anhydride gps. to alcohol OH gps. 1:(1-0.5). (X) is a triphenylmethane dyestuff. USE/ADVANTAGE - (I) is used for coating printing plates (claimed), which are claimed per se. (I) is also useful for producing images on various substrates and receptive sheets, reliefs suitable for printing plates, screen etc., as photocurable protective lacquers and for formulating UV-curable printing inks. Mixts. contg. the min. no. of constituents are used, which give properties as good as or better than usual and better photosensitivity and/or larger editions.