Abstract: Acylphosphine compounds of the formula I ##STR1## where X is oxygen, sulfur or an electron pair, R.sup.1 is R.sub.4 or OR.sup.4, R.sup.2 is --OM, where M is a monovalent cation, R.sup.3 is aryl which is substituted at least at the two positions ortho to the carbonyl group, and R.sup.4 is hydrogen, alkyl or aryl, are very effective photoinitiators for photopolymerizable materials, such as coating compositions, finishes, printing inks, unsaturated polyesters, recording media and preferably aqueous polymer dispersions or solutions.

Abstract: Acylphosphine oxide compounds of the general formula ##STR1## where R.sup.1 is alkyl, cyclohexyl, cyclopentyl, aryl which is unsubstituted or substituted by halogen, alkyl or alkoxy, or an S-containing or N-containing five-membered or six-membered heterocyclic radical,R.sup.2 has one of the meanings of R.sup.1 (but R.sup.1 and R.sup.2 may be identical or different) or is alkoxy, aryloxy or aralkoxy, or R.sup.1 and R.sup.2 together form a ring andR.sup.3 is an at least disubstituted phenyl, pyridyl, furyl or thienyl radical which carries, at least at the two carbon atoms adjacent to the linkage point of the carbonyl group, the substituents A and B, which may be identical or different, and each of which is alkyl, alkoxy or alkylthio of 1 to 6 carbon atoms, cycloalkyl of 5 to 7 carbon atoms, phenyl or halogen, or R.sup.3 is .alpha.-naphthyl substituted by A and B at least in the 2- and 8-positions or is .beta.

Abstract: Photopolymerizable mixtures comprising one or more photopolymerizable, olefinically unsaturated compounds and one or more photoinitiators or photosensitizers, with or without other conventional additives and/or assistants, contain, as an activator, a tertiary amine of the general formula (I) ##STR1## wherein R.sup.1 and R.sup.2 are each an unsubstituted alkyl, cycloalkyl or phenyl radical, hydroxyl or alkoxy, or R.sup.1 and R.sup.2 are bonded together to form a cyclic alkylene radical, R.sup.3 has the same meanings as R.sup.1 or R.sup.2 and may furthermore be hydrogen, acyloxy or substituted benzoyloxy, and R.sup.4 and R.sup.5 are each an unsubstituted or substituted alkyl, cycloalkyl or phenyl radical, or R.sup.4 and R.sup.5 are bonded together to form a cyclic alkylene or alkyleneoxyalkylene radical.

Abstract: Acylphosphine oxides of the general formula ##STR1## where R.sup.1 is methyl or ethyl, R.sup.2 is a branched or straight-chain alkyl radical or chlorine, alkoxy or hydrogen, R.sup.3 and R.sup.4 are identical or different, and are each alkyl, alkoxy, alkylthio or chlorine and R.sup.5 is hydrogen, chlorine, alkoxy, alkylthio or alkyl, may be used as photoinitiators in photopolymerizable materials.

Abstract: Acylphosphine oxide compounds of the general formula ##STR1## where R.sup.1 is alkyl, cyclohexyl, cyclopentyl, aryl which is unsubstituted or substituted by halogen, alkyl or alkoxy, or an S-containing or N-containing five-membered or six-membered heterocyclic radical,R.sup.2 has one of the meanings of R.sup.1 (but R.sup.1 and R.sup.2 may be identical or different) or is alkoxy, aryloxy or aralkoxy, or R.sup.1 and R.sup.2 together form a ring andR.sup.3 is an at least disubstituted phenyl, pyridyl, furyl or thienyl radical which carries, at least at the two carbon atoms adjacent to the linkage point of the carbonyl group, the substituents A and B, which may be identical or different, and each of which is alkyl, alkoxy or alkythio of 1 to 6 carbon atoms, cycloalkyl of 5 to 7 carbon atoms, phenyl or halogen, or R.sup.3 is .alpha.-naphthyl substituted by A and B at least in the 2- and 8-positions or is .beta.

Abstract: Unsymmetrical monoketals of aromatic 1,2-diketones ##STR1## wherein R.sup.1 and R.sup.2 are different radicals, are manufactured by reacting the corresponding aromatic 1,2-diketones, in an organic solvent, with an acid ester (R.sup.1).sub.n X as alkylating agent and an alcoholate (R.sup.2 O).sub.m Me, where n and m are integers from 1 to 3, X is an acid radical and Me is a metal of main groups 1 to 3 of the periodic table of the elements. The resulting diketone monoacetals are particularly suitable for use as photoinitiators in photopolymerizable compositions.

Abstract: A photopolymerizable composition which contains one or more olefinically unsaturated compounds and from 0.2 to 20% by weight (based on the unsaturated compound(s)) of a photoinitiator, with or without conventional additives, the photoinitiator being a mixture of one or more aromatic carbonyl compounds of the general formula (A) ##STR1## where Ar is an ortho-arylene radical which may or may not be substituted by one or more radicals R.sup.1 to R.sup.4, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different and each is H, alkyl or 1 to 5 carbon atoms, phenyl, halogen, alkoxy of 1 to 5 carbon atoms, alkaryl of 7 to 11 carbon atoms, aralkyl of 7 to 11 carbon atoms or --CO.sub.2 R.sup.9, where R.sup.9 is alkyl of 1 to 5 carbon atoms, and n is 0 or 1, and an amine, with or without an aromatic carbonyl compound which differs from (A).This photopolymerizable composition is particularly suitable for the manufacture of photopolymer printing plates and UV-curing printing inks.

Abstract: Photopolymerizable coating compositions contain, as the binder, olefinically unsaturated compounds having a boiling point above 50.degree. C, together with from 0.5 to 15% by weight of photoinitiators, based on the binder. The photoinitiators are a mixture of an aromatic carbonyl compound A, which is a derivative of benzoin or benzil, which has at least one carbon-oxygen single bond in the .alpha.-position relative to the carbonyl group, an aromatic carbonyl compound B which is derived from benzophenone, fluorenone, anthraquinone, xanthene, thioxanthone or acridone, and an amine C of the general formula ##STR1## where R', R" and R"' are H, alkyl of 1 to 10 carbon atoms, cycloalkyl of 3 to 10 carbon atoms, aryl, hydroxyalkyl of 1 to 8 carbon atoms or alkoxyalkyl of 2 to 4 carbon atoms, but at most 2 substituents are H and at most 2 substituents are aromatic.These coating compositions may be used for finishing various substrates, as fillers or as printing inks.

Abstract: A photopolymerizable composition containing olefinically unsaturated compounds, optional conventional additives and, as photoinitiator, a mixture of a thioether of the general formula (I): ##STR1## where R.sup.4 is phenyl, naphthyl, thienyl, furyl or styryl which may be substituted by one or more identical or different R.sup.5 's,R.sup.5 is phenyl, benzoyl, halogen, alkyl of 1 to 5 carbon atoms, alkyl having an --O--group and 1 to 5 carbon atoms, alkyl having an --S--group and 1 to 5 carbon atoms, alkoxyalkyl of 2 to 5 carbon atoms, alkaryl of 7 to 11 carbon atoms, aralkyl of 7 to 11 carbon atoms, NO.sub.2, CN, COOH or COOR.sup.6, R.sup.6 being an alkyl of 1 to 5 carbon atoms,A is the alkylene group C.sub.n H.sub.2n (n = an integer of 1 to 5) which may be substituted by one or more R.sup.4 's and/or R.sup.5 's, andR.sup.1, r.sup.2 and R.sup.3 may be identical or different and are each H, an R.sup.4 or an R.sup.5,and an organic amine.