Abstract: Compounds of formula X ##STR1## in which R.sub.6 is aryl, R.sub.7 is hydrogen, --OH or alkyl, R.sub.8 is alkyl, R.sub.9 is hydrogen, alkyl, alkenyl, aryl, furyl or --CCl.sub.3, when n is 1, R.sub.10 is alkyl, aryl, camphoryl, --CF.sub.3 or fluoro, or when n is 2, R.sub.10 is alkylene or arylene are latent curing catalysts for acid-curable stoving varnishes. On irradiation, the active curing catalysts which lead to acid-catalysed curing of the resins are formed from the compounds of the formula x.

Abstract: Aromatic ketones or .alpha.-diketones can be prepared from the corresponding carbinols by reaction with molar amounts of a sulfonyl chloride in the presence of a base. The corresponding sulfinic acid or salt thereof with the base is formed simultaneously.

Abstract: Propiophenones of the formula I ##STR1## in which R.sup.1 is hydrogen or C.sub.1 -C.sub.4 -alkyl, --Si(CH.sub.3).sub.3, allyl or benzyl, R.sup.2 is hydrogen, C.sub.1 -C.sub.8 -alkyl, C.sub.1 -C.sub.4 -alkyl which is substituted by C.sub.1 -C.sub.4 -alkoxy or --OH, --(CH.sub.2 --CH.sub.2 --O).sub.n --R.sup.5 where n is 2 to 20 and R.sup.5 is H or C.sub.1 -C.sub.4 -alkyl, --Si(CH.sub.3).sub.3, benzyl, C.sub.3 -C.sub.6 -alkenyl, C.sub.3 -C.sub.4 -alkynyl or 2-tetrahydrofuranyl, or R.sup.1 and R.sup.2 together are a C.sub.1 -C.sub.6 -alkylidene radical or a C.sub.2 -C.sub.6 -alkylidene radical which is substituted by hydroxyl, C.sub.1 -C.sub.4 -alkoxy or phenyl, a linear or branched C.sub.2 -C.sub.6 -alkanediyl radical, a benzylidene, cyclopentylidene or cyclohexylidene radical or a 2,2,2-trichloroethylidene, 2-furylimethylidene or dimethylsilylidene radical, R.sup.3 is phenyl which is unsubstituted or substituted by one or more --Cl, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or C.sub.1 -C.sub.

Abstract: Compounds of the formula I, II or III ##STR1## in which Ar and Ar' are an oxygen-containing aromatic radical, R.sup.1 and R.sup.2 are a monovalent hydrocarbon radical which is substituted or unsubstituted, or R.sup.1 and R.sup.2 together form alkylene, oxaalkylene or azaalkylene, R.sup.3 is a direct bond or a divalent hydrocarbon radical, X and X' are a monovalent amino group and Y is a divalent amino or diamino group, are excellent photoinitiators for the photocuring of colored, especially pigmented, compositions containing an olefinically unsaturated, photopolymerizable binder.

Abstract: Oxime sulfonates of formula I ##STR1## wherein Y is a polymerizable unsaturated group or epoxide group or an --OH, --NHR.sup.5, --COOH, COOR.sup.6, --COCl, --CH.sub.2 Hal, --SO.sub.2 Cl or --NCO group, Z is an (x+y)-valent connecting member, R.sup.1 and R.sup.2 are monovalent organic radicals, m is 0 or 1, x is 1 or 2 and y is 1 or 2, can be converted into polymers which can be thermally or photochemically dissociated to form free sulfonic acid groups. Said polymers can therefore be used as photoresists which can be developed with aqueous alkalis.

Abstract: Compounds of the formula I and II ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6, X, Y and n are as defined in claim 1, are latent curing catalysts for preparing relief images with acid-curable resins. They are distinguished by satisfactory solubility in the acid-curable resin systems, can be stored virtually indefinitely in the dark and, when exposed to shortwave light, make it possible to cure the resins by acid catalysis at a relatively low temperature.

Abstract: Compounds of formula I or II ##STR1## in which n is 1 or 2, R.sup.1 is phenyl, substituted phenyl, alkyl, substituted alkyl, hydrogen, --OH or amino, R.sup.2 is hydrogen, R.sup.3 is hydrogen, alkyl, substituted alkyl, phenyl or substituted phenyl, R.sup.4 is alkyl, phenyl, substituted phenyl, alkylene or arylene, X is --O--, --S--, --CH.sub.2 -- and Y is a direct bond or --CH.sub.2 -- are latent hardening catalysts for acid curable resins. The catalysts are activated by heat and are used in heat-hardening high-solids industrial varnishes and for coil-coatings, can and wood varnishes.

Abstract: Compounds of the formula I, II or III ##STR1## in which Ar and Ar' are an oxygen-containing aromatic radical, R.sup.1 and R.sup.2 are a monovalent hydrocarbon radical which is substituted or unsubstituted, or R.sup.1 and R.sup.2 together form alkylene, oxaalkylene or azaalkylene, R.sup.3 is a direct bond or a divalent hydrocarbon radical, X and X' are a monovalent amino group and Y is a divalent amino or diamino group, are excellent photoinitiators for the photocuring of colored, especially pigmented, compositions containing an olefinically unsaturated, photopolymerizable binder.

Abstract: Oxime sulfonates of the formula I ##STR1## in which m is 0 or 1 and n is 1 or 2, R.sup.1 and R.sup.2 are monovalent radicals or, together with the atoms to which they are linked, form a ring system, and R.sup.3 is the n-valent radical of a mono- or di-sulfonic acid, can be split photochemically to give the free sulfonic acid. They can therefore be used as latent acid catalysts for combined radiation curing and heat curing of acid-curable finishes.

Abstract: Compounds of the formula I and II ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6, X, Y and n are as defined in claim 1, are latent curing catalysts for acid-curable stoving lacquers. They are distinguished by satisfactory solubility in the acid-curable resin systems, can be stored virtually indefinitely in the dark and, when exposed to shortwave light, make it possible to cure the resins by acid catalysis at a relatively low temperature.

Abstract: Compounds of the formula I ##STR1## in which R.sub.1, is aryl, R.sub.2 is hydrogen, --OH or alkyl, R.sub.3 is hydrogen or alkyl, R.sub.4 is hydrogen, aryl, alkenyl, furyl or --CCl.sub.3, when n is 1, R.sub.5 is alkyl, aryl, camphoryl, --CF.sub.3 or fluoro, or when n is 2, R.sub.5 is alkylene or arylene, are latent curing catalysts for acid-curable stoving varnishes. On irradiation, the active curing catalysts which lead to acid-catalyzed curing of the resins are formed from the compounds of the formula I.

Abstract: Compounds of the formula I, II, III, IV or V ##STR1## in which Ar, X, Y, Y', R.sup.1 to R.sup.5 and R.sup.1' to R.sup.5' are as defined in claim 1, can be used as photoinitiators for the photopolymerization of unsaturated compounds. They can be prepared by a Diels-Alder reaction and/or a Grignard reaction.