Abstract: New carbonyl derivatives of 1-phenylindan suitable for use as photoinitiators in the photopolymerization of compounds or mixtures of compounds containing ethylenic double bonds.The carbonyl derivatives of 1-phenylindan according to the present invention possess high efficiency as photoinitiators in terms both of the concentration used and the photopolymerization rate.

Abstract: The ultraviolet-curable organoploysiloxane composition of the invention comprises (A) an organopolysiloxane having bonded to a silicon atom thereof a silyl-substituted ethyl group represented by the general formula[CH.sub.2 .dbd.CR.sup.1 --CO--O--(--CH.sub.2 --).sub.a --SiR.sup.2.sub.2 --](R.sup.2 .sub.3 Si--O--).sub.c R.sup.2.sub.2--c Si--C.sub.2 H.sub.4 --,in which R.sup.1 is a hydrogen atom or a methyl group, R.sup.2 is a monovalent hydrocarbon group, a is 1, 2 or 3 and c is 1 or 2, and (B) a photopolymerization initiator. The composition is rapidly cured by ultraviolet irradiation into a gel-like material having adhesiveness without the disadvantages of catalyst poisoning and undue volume shrinkage so that the composition is useful as a potting agent in electronic and electric components.

Abstract: A positive-working photoresist composition is disclosed. The composition comprises a light-sensitive compound represented by general formula (A) and an alkali-soluble novolak resin. ##STR1## wherein R.sub.a, R.sub.b, R.sub.c, R.sub.d, R.sub.e and R.sub.f, which may be the same or different, each represents H, --X--R.sub.1, ##STR2## provided that among the six substituents represented by R.sub.a to R.sub.f, the number of the substituents representing H is a real number of more than 0 and not more than 3 calculated in terms of average value per molecule of the light-sensitive compound, the number of the substituents representing --X--R.sub.1 is a real number of not less than 0.3 calculated in terms of average value per molecule of the light-sensitive compound, and the number of the substituents representing ##STR3## is a real number of not less than 2.5 caluclated in terms of average value per molecule of the light-sensitive compound; X represents a simple bond, ##STR4## R.sub.

Abstract: An active energy ray-curable resin composition comprises (A) a graft copolymerized polymer comprising graft chains composed mainly of structural units derived from at least one monomer selected from the group consisting of (a) hydroxyl containing (meth)acrylic monomers, (b) amino or alkylamino containing (meth)acrylic monomers, (c) carboxyl containing (meth)acrylic or vinyl monomers, (d) N-vinylpyrrolidone, (e) vinylpyridine or its derivatives and (f) (meth)acrylic amide derivatives represented by the general formula (II) shown below: ##STR1## (wherein R.sub.1 is hydrogen or methyl group and R.sub.2 is hydrogen or an alkyl or acyl group having 1 to 4 carbon atoms which may have hydroxyl group added to trunk chains composed mainly of structural units compsiting at least one monomer selected from the group consisting of the monomer represented by the general formula (I) shown below: ##STR2## (wherein R.sub.1 to R.sub.

Abstract: An active energy beam-curable type resin composition, which comprises (A) a graft copolymer comprising a main chain composed mainly of structural units of monomers containing one (meth)acryloyl group and a dicyclopentenyl derivative group represented by the following general formula (I): ##STR1## wherein Z represents a five-membered ring given by ##STR2## and R.sub.1 and R.sub.

Abstract: A new class of polymeric or polymerizable aromatic-aliphatic ketones, the preferred of which are: 2-hydroxy-2-methyl(4-vinylpropiophenone), 2-hydroxy-2-methyl-p(1-methylvinyl)propiophenone, p-vinylbenzoylcyclohexanol, p-(1-methylvinyl)benzoyl-cyclohexanol and their oligomerization and polymerization products, they being suitable for use as photoinitiators for the photopolymerization of ethylenically unsaturated monomers and prepolymers.Said ketones are produced by subjecting an aromatic substrate, preferably a monomer or oligomer of styrene type, to the following reaction cycle: polymerization - acylation - alphachlorination - nucleophilic substitution with the formation of epoxyether - hydrolysis of the epoxyether; or to other reactions as modifications or alternatives to this cycle.The ketones according to the present invention have high efficiency as photoinitiators both with regard to the useful concentration to be used and with regard to the polymerization rate.

Abstract: Polyorganosiloxanes having an average of more than two siloxane repeat units, at least one of which repeat units includes a photoinitiating group bound to the silicon atom thereof, the photoinitiating group having the formula ##STR1## where R.sup.1 and R.sup.2 are the same or different alkyl groups or R.sup.1 and R.sup.2 are alkylene groups linked to each other so that R.sup.1 and R.sup.2 together with the carbon atom to which both are attached comprise a cycloalkyl group, and R.sup.3 is H or hydrocarbyl.Compositions of these polyorganosiloxanes and silicones or organic monomers with free radical curable groups are readily cured by irradiation with UV light.

Abstract: Compounds of the formula I, II or III ##STR1## in which Ar is a sulfur-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 is a monovalent amino group and X' is a divalent amino or diamino group, are excellent photoinitiators for the photocuring of colored, in particular pigmented, compositions containing an olefinically unsaturated, photopolymerizable binder.