| abstract |
Radiation-sensitive composition comprising (a) at least one photopolymerizable compound with at least one ethylenically unsaturated group accessible to a free-radical polymerization, wherein the at least one photopolymerizable compound has a molecular weight of 3,000 or less and can be obtained by reacting a diisocyanate with (I) an ethylenically unsaturated compound with a hydroxy group, and at the same time (ii) a saturated organic compound with an NH group and an OH group, wherein the reactants are used in amounts according to the following condition: Number of moles of isocyanate groups ≦number of moles of OH plus NH groups; (b) at least one sensitizer which absorbs radiation from the wavelength range of 250 to 450 nm of the electromagnetic spectrum and is selected from: dihydropyridines of formula (I) and oxazole derivatives of formula (II): (II) (c) at least one coinitiator capable of forming free radicals together with the sensitizer (b) and selected from 2,2′,4,4′,5′5-hexaarylbiimidazoles, compounds with at least one photolytically cleavable trihalogenmethyl group, diaryliodonium salts, triarylsulfonium salts and N-heterocyclic compounds with at least one nitrogen atom in the ring, having an oxy substituent at least one ring nitrogen atom, and mixtures of the above compounds; and (d) optionally one or more components selected from alkali-soluble binders, colorants, exposure indicators, plasticizers, chain transfer agents, leuco dyes, surfactants, inorganic fillers and thermopolymerization inhibitors; with the proviso that the radiation-sensitive composition does not comprise a metallocene. |