Abstract: Titanocenes of the formula I ##STR1## in which R.sup.1 are cyclopentadienyl.sup..crclbar. groups and R.sup.2 and R.sup.3 are aromatic radicals which are substituted in both ortho-positions by fluorine and, in addition, are substituted by an acyloxy group are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds.

Abstract: Titanocenes of the formula I ##STR1## in which R.sup.1 are cyclopentadienyl.sup..crclbar. groups and R.sup.2 and R.sup.3 are aromatic radicals which are substituted in both ortho-positions by fluorine and, in addition, are substituted by an acyloxy group are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds.

Abstract: Titanocenes with, for example, .pi.-cyclopentadienyl ligands in which one or two carbo- or heterocyclic aromatic rings are bonded to the titanium, the aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the metal-carbon bond and being substituted by at least one free or etherified or esterified polyoxaalkylene radical, are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated substrates.

Abstract: Titanocenes containing two 5-membered cyclodienyl gropus, for example cyclopentadienyl, and one or two 6-membered carbocyclic or 5- or 6-membered heterocyclic aromatic rings which are substituted by a fluorine atom in at least one of the two ortho-positions to the titanium-carbon bond and contain, as further substituents, a substituted amino radical, are suitable as photoinitiators for radiation-induced polymerization of ethylenically unsaturated compounds.

Abstract: The present invention relates to compositions comprising(a) a titanocene photoinitiator of the formula I ##STR1## (b) a 3-ketocoumarin of the formula II ##STR2## in which both R.sup.1, R.sup.2 and R.sup.3 are as defined in claim 1, R.sup.4 is a radical of the formula V ##STR3## R.sup.5 is C.sub.1 -C.sub.20 alkyl, cycloalkyl having 5-7 ring carbon atoms, phenyl or naphthyl which are unsubstituted or substituted by one to three C.sub.1 -C.sub.6 alkyl groups, C.sub.1 -C.sub.6 alkoxy groups or halogen atoms or by one diphenylamino or C.sub.1 -C.sub.6 dialkylamino group, or is C.sub.7 -C.sub.9 aralkyl, a radical --(CH.dbd.CH).sub.a --C.sub.6 H.sub.5 or a radical of the formula V, a is 1 or 2, preferably 1, and R.sup.10, R.sup.11, R.sup.12, R.sup.13 and R.sup.14 independently of one another are hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, phenyl, tolyl, xylyl or benzyl, and R.sup.11 can additionally also be a group --NR.sup.15 R.sup.16 or --OR.sup.15, wherein R.sup.15 and R.sup.

Abstract: Titanocenes with, for example, .pi.-cyclopentadienyl ligands in which one or two carbo- or heterocyclic aromatic rings are bonded to the titanium, the aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the matal-carbon bond and being substituted by at least one free or etherified or esterified polyoxaalkylene radical, are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated substrates.

Abstract: Titanocenes containing .pi.-cyclopentadienyl ligands, in which one or two carbocyclic or heterocyclic aromatic rings are attached to the metal atom, said aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the metal-carbon bonds, are suitable photoinitiators for the photopolymerization of ethylenically unsaturated substrates. They are distinguished by high sensitivity, stability to air and heat, and are very effective in the range from UV light to visible light.

Abstract: Compounds of the formulae I and Ia ##STR1## in which R.sup.1 is a group which can be transferred to carbonyl or imine compounds, for example alkyl, allyl, vinyl or the radical of an enol or enamine, R.sup.2 is, for example, cyclopentadienyl, R.sup.3 is the radical of an optically active sugar or sugar derivative, Me is Ti, Zr or Hf, x is 0, 1 or 2 and y is 0, 1, 2 or 3, M.sup..sym. is Li.sup..sym., Na.sup..sym., K.sup..sym., MgY.sup..sym., ZnY.sup..sym., CdY.sup..sym., HgY, CuY.sup..sym. or quaternary ammonium, Y being halogen, are suitable for use as chiral reactants for compounds containing aldehyde, keto and/or N-substituted imine groups.

Abstract: Titanocenes containing .pi.-cyclopentadienyl ligands, in which one or two carbocyclic or heterocyclic aromatic rings are attached to the metal atom, said aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the metal-carbon bonds, are suitable photoinitiators for the photopolymerization of ethylenically unsaturated substrates. They are distinguished by high sensitivity, stability to air and heat, and are very effective in the range from UV light to visible light.

Abstract: Titanocenes with, for example, .pi.-cyclopentadienyl ligands in which one or two carbo- or heterocyclic aromatic rings are bonded to the titanium, the aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the metal-carbon bond and being substituted by at least one free or etherified or esterified polyoxaalkylene radical, are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated substrates.

Abstract: Titanocenes with .pi.-cyclopentadienyl ligands, in which one or two carbocyclic or heterocyclic aromatic rings are bonded to the metal, the aromatic rings being substituted in at least one of the two ortho-positions relative to the metal-carbon bonds by CF.sub.2 Z (Z=F or substituted or unsubstituted alkyl), are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds. They are distinguished by a high radiation sensitivity, stability to air and thermal effects, and high effectiveness in the range from UV light to visible light.

Abstract: Compounds of the forulae I and Ia ##STR1## in which R.sup.1 is a group which can be transferred to carbonyl or imine compounds, for example alkyl, allyl, vinyl or the radical of an enol or enamine, R.sup.2 is, for example, cyclopentadienyl, R.sup.3 is the radical of an optically active sugar or sugar derivative, Me is Ti, Zr or Hf, x is 0, 1 or 2 and y is 0, 1, 2 or 3, M.sym. is Li.sym., Na.sym., K.sym., MgY.sym., ZnY.sym., CdY.sym., HgY, CuY.sym. or quaternary ammonium, Y being halogen, are suitable for use as chiral reactants for compounds containing aldehyde, keto and/or N-substituted imine groups.

Abstract: Titanocenes with .pi.-cyclopentadienyl ligands, in which one or two carbocyclic or heterocyclic aromatic rings are bonded to the metal, the aromatic rings being substituted in at least one of the two ortho-positions relative to the metal-carbon bonds by CF.sub.2 Z (Z=F or substituted or unsubstituted alkyl), are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds. They are distinguished by a high radiation sensitivity, stability to air and thermal effects, and high effectiveness in the range from UV light to visible light.

Abstract: Titanocenes containing .pi.-cyclopentadienyl ligands, in which one or two carbocyclic or heterocyclic aromatic rings are attached to the metal atom, said aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the metal-carbon bonds, are suitable photoinitiators for the photopolymerization of ethylenically unsaturated substrates. They are distinguished by high sensitivity, stability to air and heat, and are very effective in the range from UV light to visible light.

Abstract: The invention relates to photopolymerizable compositions comprising (a) a prepolymer containing photopolymerizable olefinic double bonds, (b) photoinitiator of the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined in claim 1, and optionally (c) an ester of acrylic or methacrylic acid or an allyl ether or allyl ester of a polyol.Owing to their excellent light sensitivity, these compositions are suitable for the economic production of high temperature resistant protective layers and relief structures having excellent resolution and good contours.