Abstract: A method for hydrophilizing a hydrophobic plastic surface which exhibits a hydrophobic polymer that has hydrogens that bind to sp.sup.3 -hybridized carbon atoms, characterized by the steps of: (i) contacting the plastic surface with a liquid having dissolved therein (a) a hydrogen-abstracting UV-initiator and (b) a hydrophilic polymer which has one or more alkene groups; and (ii) irradiating the solution with UV light which activates the initiator.

Abstract: A process for photocatalytic polymerisation of a cyclic olefin or of at least two different cyclic olefins in the presence of a metal compound as catalyst, which process comprises carrying out a photochemically induced ring-opening metathesis polymerisation in the presence of a catalytic amount of at least one thermostable molybdenum (VI) or tungsten (VI) compound which contains at least two methyl groups or two monosubstituted methyl groups lacking .beta.-hydrogen atoms in the substituent and which are bonded to the metal atom. The process may be carried out by first irradiating and terminating the polymerisation by heating. The process is suitable for fabricating moulded articles, coatings and relief images.

Abstract: A method of generating reactive species which includes exposing a photoreactor composition to radiation, in which the photoreactor composition comprises a wavelength-specific sensitizer associated with a reactive species-generating photoinitiator. Also described are methods of polymerizing unsaturated monomers and curing an unsaturated oligomer/monomer mixture.

Abstract: n and m are independently of one another 0 or 1,R.sub.1, R.sub.2, R.sub.3, R.sub.4 and X are as defined in claim 1,are suitable as photoinitiators for the polymerization of ethylenically unsaturated compounds.

Abstract: Sulfonic acid esters are used as (a) compounds for forming a strong acid on irradiation in radiation-sensitive, positive or negative working mixtures also comprising (b) either a compound with at least one acid-decomposable C--O--C or C--O--Si bond (for positive working mixtures) or a compound with at least acid-cross-linkable groups (for negative working mixtures) and c) a binder which is insoluble in water but soluble or at least swellable in aqueous alkaline solutions, wherein said sulfonic acid esters are formula?R.sup.1 --CR.sup.2 (CF.sub.3)--O--SO.sub.2 --!.sub.n R.sup.3(I)orR.sup.1 ?--CR.sup.2 (CF.sub.3)--O--SO.sub.2 --R.sup.3 !m (II)wherein R.sup.1, R.sup.2, R.sup.3, n and n are defined with the body of the disclosure. These mixtures are particularly suitable for exposure to deep UV radiation in the formation of recording materials suitable for the production of photoresists, electronic components, and printing plates.

Abstract: A process for preparing thioxanthone and derivatives thereof is disclosed. In the process, an aromatic compound, such as cumene, is reacted with thiosalicylic acid (TSA) or dithiosalicylic acid (DTSA) in the presence of sulfuric acid. The reaction mixture, which includes thioxanthone or a derivative thereof, is thereafter distilled under reduced pressure to recover the thioxanthone compound.

Abstract: The present invention relates to initiators for the polymerization and/or crosslinking, cationically and under photochemical and/or thermal activation and/or activation by a beam of electrons, of monomers and/or polymers containing organofunctional groups.The said initiators are of the type comprising an onium salt of an element from groups 15 to 17 of the Periodic Table (Chem & Eng News, Vol 63, N5, 26, of 4 Feb. 1985) and they are characterized in that they contain at least one polymerization and/or crosslinking accelerator chosen from .alpha.-hydroxylated carboxylic acid esters such as, for example, lactic acid esters. Another subject of the invention is compositions based on at least one cationically crosslinkable polyorganosiloxane and on at least one initiator.

Abstract: Pressure sensitive adhesives that cure to a high cohesive strength at room and elevated temperatures, and a method for making such adhesives, are provided. The adhesives comprise an acrylic copolymer compounded with a pigment and a hydrogen-abstracting photoinitiator. A tackifier and/or multifunctional acrylate or methacrylate can also be added. The acrylic copolymer is prepared from a substantially acid-free monomer mixture of at least one alkyl acrylate and a tertiary amine-containing monomer, such as DMAPMA. Other monomers, including polar vinylic monomers and diesters of ethylenically unsaturated dicarboxylic acids are, preferably, also included. Despite the presence of titanium dioxide or other pigments, the compounded copolymers are UV-cured to a high cohesive strength through the combination of tertiary amine functional groups and hydrogen-abstracting photoinitiators, which form synergistic pairs when irradiated, leading to free radical formation and polymer cross-linking.

Abstract: Novel onium borates of an element of Groups 15 to 17 of the Periodic Table, or borates of an organometallic complex of an element of Groups 4 to 10 of the Periodic Table, well suited for the photochemical/electron beam cationic initiation of polymerization/crosslinking, the anionic borate moiety of which having the formula:[BX.sub.a R.sub.b ].sup.-in which a and b are integers ranging from 0 to 4 and a+b=4; the symbols X are each a halogen atom when a ranges up to 3 and an OH functional group when a ranges up to 2; and the symbols R, which may be identical or different, are each a phenyl radical substituted by at least one element or electron-withdrawing substituent or by at least two halogen atoms, or an aryl radical containing at least two aromatic ring members, or such aryl radical bearing at least one electron-withdrawing substituent.

Abstract: The invention relates to the use of oxime sulfonates of formula 1 ##STR1## wherein R is naphthyl, ##STR2## Ar is an unsubstituted aryl group or an aryl group which carries one or more than one substituent selected from the group consisting of nitro, chloro, bromo, hydroxyl, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 perfluoroalkyl, C.sub.1 -C.sub.4 alkoxy and acid degradable substituents;R.sub.0 is either a R.sub.1 --X group or R.sub.2 ;X is an oxygen or a sulfur atom;R.sub.1 is hydrogen, C.sub.1 -C.sub.4 alkyl or unsubstituted phenyl or phenyl which is substituted by a member selected from the group consisting of chloro, bromo, C.sub.1 -C.sub.4 alkyl and C.sub.1 -C.sub.4 alkoxy, andR.sub.2 is hydrogen, C.sub.1 -C.sub.

Abstract: A polymer composite is described having a bicontinuous structure of two substantially nonporous phases, one being a hydrophilic polymer and the other being a hydrophobic polymer. The bulk properties of both polymers are retained in the polymer composite. The composite is prepared from a microemulsion comprising a free-radically ethylenically unsaturated polar species in the aqueous phase, a free-radically ethylenically unsaturated hydrophobic monomer in the oil phase, and surfactant.

Abstract: A radiation-curable release composition is disclosed which comprises:(A) an organopolysiloxane represented by the formulaRSi(CH.sub.3).sub.2 --O--(Si(CH.sub.3).sub.2 O).sub.n (Si(CH.sub.3)(R)O).sub.m Si(CH.sub.3).sub.2 R (I)wherein in Formula (I), each R is --R.sup.1 --O(O)C--C(R.sup.2).dbd.CH.sub.2, --R.sup.1 --O--C(R.sup.2).dbd.CH.sub.2 or is derived from an organic molecule containing both ethylenic unsaturation and epoxide functionality; R.sup.1 is a hydrocarbylene group; each R.sup.2 is independently hydrogen or a methyl or ethyl group; m is a number from about 1 to about 15; and n is a number from about 50 to about 300; and(B) an organosiloxane copolymer represented by the formula(R.sub.3 SiO).sub.x (SiO.sub.4/2).sub.y (II)wherein in Formula (II), each R is independently a hydrocarbon group or a group represented by the formula--O(O)C--C(R*).dbd.CH.sub.2wherein R* is hydrogen or a methyl or ethyl group; x is a number from about 0.

Abstract: Photopolymerization initiator for the visible light-polymerizing adhesives; and the visible light-polymerizing adhesives comprising the photopolymerization initiator, an aliphatic tertiary amine and a radical polymerizing monomer. The visible light-polymerizing adhesive of the invention has good transparency without coloring after photopolymerization as well as good adhering activity. It also has colorless, good transparency after photopolymerization and good adhering activity in an UV irradiation test, as well as excellent light resistance showing very little color change and deterioration in an UV irradiation test. The visible light-polymerizing adhesive of the invention is also excellent in photopolymerizing activity. Furthermore, the visible light-polymerizing adhesive of the invention has photopolymerizing activity not only to visible light but also to near-UV. It hardly has problems of such decrease in transparency caused by both kinds of lights as coloring and color change.

Abstract: A photopolymerizable composition comprising a crosslinking agent, a UV sensitive photopolymerization initiator and a thioether compound having a vinyl ester or vinyl amide component; wherein the crosslinking agent and the thioether may be the same compound.

Abstract: A polymer composite is described having a bicontinuous structure of two substantially nonporous phases, one being a hydrophilic polymer and the other being a hydrophobic polymer. The bulk properties of both polymers are retained in the polymer composite. The composite is prepared from a microemulsion comprising a free-radically ethylenically unsaturated polar species in the aqueous phase, a free-radically ethylenically unsaturated hydrophobic monomer in the oil phase, and surfactant.

Abstract: Compounds of the formula I ##STR1## in which X is O, S, SO, SO.sub.2 or NR.sub.13, R.sub.13 is, for example, methyl, and R.sub.1 to R.sub.12, independently of one another, are, for example, H, C.sub.1 -C.sub.12 alkyl, C.sub.1 14 C.sub.12 alkoxy, halogen or --CN. The compounds are photosensitive and photochromic and as suitable are photosensitizers and simultaneously as colour indicators, and as photoswitchable colour filters.

Abstract: A UV curable organic solvent soluble, aqueous nonalkaline soluble and peelable temporary solder mask composition to be applied to a surface to be protected, having a reactive diluent monomer capable of polymerization upon exposure to ultraviolet light and a photoinitiator serving as a free radical source to initiate polymerization.

Abstract: The invention relates to adhesive compositions comprising terpolymers C.sub.6 to C.sub.10 unsaturated .alpha.-olefin monomers, C.sub.2 to C.sub.5 .alpha.-olefin monomers and polyene monomers and an effective amount of photoactive cross-linking agent to cross-link composition upon radiation from a source of active radiation.

Abstract: The present invention relates to thioxanthone sensitizers for radiation sensitive polyimide compositions for use in manufacturing integrated circuits such as chips, thin film packaging and printed circuit boards.

Abstract: A lithographic coating and method of framing a lithographic image are disclosed. The method comprises coating at least a portion of a surface of an article with a radiation-crosslinkable polymer, and exposing the coated surface to a pattern of radiation to crosslink the polymer in a lithographic image. The functionalized polymer is a copolymer of an isoolefin of 4 to 7 carbon atoms and para-alkylstyrene, wherein the para-alkylstyrene is functionalized with a radiation reactive group at the para-alkyl group of the para-alkylstyrene.

Abstract: Bisacylphosphine sulfides of formula I ##STR1## wherein R.sub.1 is unsubstituted C.sub.1 -C.sub.18 or C.sub.1 -C.sub.8 alkyl which is substituted by phenyl, --CN, C.sub.1 -C.sub.12 alkoxy or halogen, C.sub.2 -C.sub.18 alkenyl, unsubstituted C.sub.5 -C.sub.8 cycloalkyl or C.sub.5 -C.sub.8 cycloalkyl which is substituted by C.sub.1 -C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy or halogen, unsubstituted C.sub.6 -C.sub.12 aryl or C.sub.6 -C.sub.12 aryl which is substituted by halogen, C.sub.1 -C.sub.12 alkyl or C.sub.1 -C.sub.12 alkoxy, or a 5- or 6-membered aromatic heterocyclic radical which contains oxygen, sulfur and/or nitrogen and is unsubstituted or substituted by halogen, C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, andR.sub.2 and R.sub.3 are each independently of the other unsubstituted C.sub.1 -C.sub.18 alkyl or C.sub.1 -C.sub.8 alkyl which is substituted by phenyl, halogen or C.sub.1 -C.sub.12 alkoxy, C.sub.2 -C.sub.6 alkenyl, unsubstituted C.sub.5 -C.sub.8 cycloalkyl or C.sub.5 -C.sub.

Abstract: A process is described for photoinitiated control of inorganic network fotion in the sol-gel process, which comprises eitherA) subjecting one or more hydrolytically polycondensable compounds of constituent elements of glass or ceramic, excluding silicon compounds containing polymerizable organic groups, to hydrolytic polycondensation in a liquid reaction medium to form a sol andirradiating the resulting sol in a structured or unstructured manner in the presence of a photoinitiator which can change the pH of the reaction medium on irradiation, using radiation of a wavelength range in which the photoinitiator absorbs;orB) liberating water in an anhydrous reaction medium which contains an alcohol, one or more hydrolytically polycondensable compounds of constituent elements of glass or ceramic and a photoinitiator which can liberate water by a photochemical reaction or a secondary reaction when irradiated, by structured or non-structured irradiation using radiation of a wavelength range in which the photoinitiato

Abstract: An improved photoimagable cationically polymerizable epoxy based coating material is provided. The material includes an epoxy resin system consisting essentially of between about 10% and about 80% by weight of a polyol resin which is a condensation product of epichlorohydrin and bisphenol A having a molecular weight of between about 40,000 and 130,000; between about 20% and about 90% by weight of an epoxidized octafunctional bisphenol A formaldehyde novolak resin having a molecular weight of 4,000 to 10,000; and if flame retardancy is required between about 35% and 50% by weight of an epoxidized glycidyl ether of tetrabromo bisphenol A having a softening point of between about 60 C. and about 110 C. and a molecular weight of between about 600 and 2,500. To this resin system is added about 0.

Abstract: A photopolymerizable rubber being obtained by copolymerizing four compounds consisting of a dienic liquid rubber having hydroxyl groups, an ethylenically unsaturated monomer having hydroxyl groups, a dihydric alcohol having a molecular weight of less than 2,000 and a diisocyanate compound. The photocured product of this composition has higher tensile strength and elongation than that of the prior photopolymerizable rubbers.

Abstract: An improved photoimagable cationically polymerizable epoxy based coating material is provided, that is suitable for use on a variety of substrates. The material includes an epoxy resin system consisting essentially of between about 10% and about 80% by weight of a polyol resin which preferably is a condensation product of epichlorohydrin and bisphenol A having a molecular weight of between about 40,000 and 130,000; and between about 35% and 72% by weight of an epoxidized glycidyl ether of a brominated bisphenol A having a softening point of between about 60.degree. C. and about 110.degree. C. and a molecular weight of between about 600 and 2,500. A third resin, either an epoxy cresol novolak or a polyepoxy resin, is also added to the resin system. To this resin system is added about 0.

Abstract: A photopolymerizable composition comprises at least one addition polymerizable compound having at least one ethylenically unsaturated bond and at least one photopolymerization initiator represented by the following general formula (I): ##STR1## wherein R.sub.1 to R.sub.4 independently represent hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, hydroxyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted amino group with the proviso that R.sub.1 to R.sub.4 may form a non-metallic ring together with the carbon atoms bonded thereto; R.sub.5 and R.sub.6 each represents hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a heteroaromatic group, an acyl group, cyano group, an alkoxycarbonyl group, carboxyl group or a substituted alkenyl group with the proviso that R.sub.5 and R.sub.

Abstract: An optical molding composition is used for casting and does not cause irritation to the skin or possess a bad smell. This composition comprises1. an actinic radiation-curable, radical-polymerizable organic compound comprising(1) one or more polythiol compounds and(2) one or more polyene compounds each having at least two actinic radiation-reactive carbon-to-carbon double bonds in the molecule, and2. an actinic radiation-sensitive radical polymerization initiator.

Abstract: The invention relates to a method for the photochemical conversion of tachysterol compounds into previtamin D compounds and of trans-vitamin D compounds into cis-vitamin D compounds under the influence of radiation, by exposing the tachysterol compound and trans-vitamin D compound, respectively, dissolved in a suitable solvent system, in the presence of a polymeric photosensitizer consisting of a polymer chain ("backbone") comprising covalently bound sensitizers suitable for the photochemical conversion, to light with a wavelength of preferably between approx. 300 and approx.

Abstract: A resin composition, particularly for an ink printing composition, comprising a polyurethane (meth-) acrylate resin, N-vinylpyrrolidone, and acryloylmorphline, with a photoinitiator when used as an ultraviolet raycurable ink printing composition, and without a photoinitiator when used as an electron beam-curable ink printing composition.

Abstract: An ultraviolet-hardenable adhesive for bonding a non-water swellable, ophthalmic-lens to a support member, in producing a non-water swellable ophthalmic lens, the adhesive containing at least one photopolymerizing monomer, and at least one photoinitiator, the at least one photopolymerizing monomer being selected from the group consisting of acrylates or methacrylates represented by following general formulas (I) and (II): ##STR1## wherein R.sub.1 is hydrogen or methyl,R.sub.2 is hydrogen or methyl,R.sub.3 is hydrogen or methyl,m is a positive integer from 2 to 20, andn is a positive integer from 1 to 5.A method of bonding a lens blank to a support member with an adhesive, and a processing of manufacturing a lens using an adhesive, are also disclosed.

Abstract: A radiation sensitive plate comprises a substrate coated with a photopolymerizable composition. The composition comprises a polymerizable compound containing ethylenic unsaturation, a perester photoinitiator and optionally an optical sensitiser. The substrate may be a sheet of grained and anodized aluminum and the plate is useful in the production of lithographic printing plates.

Abstract: A photoresist composition is disclosed. The photoresist composition comprises a base resin, a photosensitizer, and a solvent. The base resin comprises polyhydroxystyrene represented by the following structural formula (I): ##STR1## (wherein k is a positive integer). The photosensitizer comprises a polyhalogen compound(s). The photoresist composition of the present invention has dry etching resistance characteristics comparable to those of conventional positive novolak photoresist compositions and can form a resist pattern with a high resolution and vertical sidewall profiles. This makes microprocessing possible.

Abstract: A positive working light-sensitive composition which comprises:(a) 10 to 95% by weight of a compound which has at least one acid-decomposable group and whose solubility in an alkaline developer increases by the action of an acid,(b) 0.01 to 20% by weight of a disulfone compound represented by the formula (I):R.sup.1 --SO.sub.2 --SO.sub.2 --R.sup.2 (I)wherein R.sup.1 and R.sup.2 may be same or different and represent substituted or unsubstituted alkyl groups, substituted or unsubstituted alkenyl groups or substituted or unsubstituted aryl groups, and(c) 3 to 85% by weight of a water-insoluble but alkaline water-soluble resin,wherein the optical density at 248 nm of 1 .mu.m thick coating of the composition is not more than 1.4 and the optical density at 248 nm of the coating exposed to light of 248 nm is less than the optical density of the coating before exposed to light.The light-sensitive composition is highly responsive to light of Deep-UV regions and excellent in image resolution.

Abstract: A light-sensitive composition comprises a photo-crosslinkable polymer having a photo-dimerizable unsaturated bond and a sensitizer represented by the following general formula (I): ##STR1## wherein R.sub.1 and R.sub.2 each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a substituted or unsubstituted allyl group, provided that R.sub.1 and R.sub.2 may form a ring together with the carbon atoms to which they are attached; n represents 0, 1 or 2; and G.sub.1 and G.sub.2 each independently represents a hydrogen atom, a cyano group, a substituted or unsubstituted alkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted arylcarbonyl group, an alkylthio group, an arylthio group, an alkylsulfonyl group, an arylsulfonyl group or a fluoroalkylsulfonyl group, provided that G.sub.1 and G.sub.

Abstract: A photopolymerizable composition comprises an addition polymerizable compound having at least one ethylenically unsaturated double bond and a photopolymerization initiator, wherein it comprises a compound represented by the following general formula (I) as the photopolymerization initiator: ##STR1## (wherein R.sub.1 and R.sub.2 may be the same or different and each independently represents a substituted or unsubstituted alkyl, aryl or alkenyl group or R.sub.1 and R.sub.2 may form a non-metallic ring together with the sulfur atoms to which they are bonded; n is 0, 1 or 2; G.sub.1 and G.sub.2 may be the same or different and each represents a hydrogen atom, a cyano group or a substituted or unsubstituted alkoxycarbonyl, aryloxycarbonyl, acyl, arylcarbonyl, alkylthio, arylthio, alkylsulfonyl, arylsulfonyl or fluoroalkylsulfonyl group, provided that G.sub.1 and G.sub.2 do not simultaneously represent hydrogen atoms or G.sub.1 and G.sub.

Abstract: An aqueous photopolymer composition is produced by adding a monomer to a latex of a partially neutralized carboxylated acrylic copolymer, having an acid number greater than 80, along with photoinitator and components to produce an aqueous coatable and alkali developable photoresist composition. Preferred neutralization is 30-50% for dip-coating and 40-60% for screen-printing to produce 1 mil lines and 1 mil space after ultraviolet exposure and mild alkali development.

Abstract: An improved photoimagable cationically polymerizable epoxy based coating material is provided. The material includes an epoxy resin system consisting essentially of between about 10% and about 80% by weight of a polyol resin which is a condensation product of epichlorohydrin and bisphenol A having a molecular weight of between about 40,000 and 130,000; between about 20% and about 90% by weight of an epoxidized octafunctional bisphenol A formaldehyde novolak resin having a molecular weight of 4,000 to 10,000; and if flame retardancy is required between about 35% and 50% by weight of an epoxidized glycidyl ether of tetrabromo bisphenol A having a softening point of between about 60.degree. C. and about 110.degree. C. and a molecular weight of between about 600 and 2,500. To this resin system is added about 0.

Abstract: The photopolymerizable mixture described contains(A) at least one ethylenically unsaturated photopolymerisable compound,(B) a photoinitiator of the formula I ##STR1## and (C) a photosensitiser from the group of aromatic carbonyl compounds having a triplet energy of 225-310 kJ/mol, for example xanthones, thioxianthones, coumarins, phthalimides, phenones and the like.Ar is phenyl substituted in the 4-position by a substituted amino group, R.sup.1 and R.sup.2 are alkyl, R.sup.3 and R.sup.4 are alkyl or alkoxyalkyl, or R.sup.3 and R.sup.4 together are 3-oxapentamethylene. Said sensitisers (C) raise the activity of said photoinitiators (B) without shortening the shelf life of the mixtures. The photocurable mixtures are used especially as binders for printing inks or paints.

Abstract: A photoinitiator composition comprising (1) an aminobenzylidene carbonyl compound and (2) an N-aryl-.alpha.-amino acid is suitable for use in a photo-polymerizable composition comprising (a) an addition-polymerizable compound having a boiling point of 100.degree. C. or higher at an atmospheric pressure and (b) said photoinitiator composition.

Abstract: A photopolymerizable mixture is described comprising (a) a polymeric binder, (b) an acrylate or alkacrylate of a polyhydric alcohol, said compound comprising at least one group which is photooxidizable on exposure to actinic radiation in the presence of a photoreduciable dye, (c) a photoinitiator comprising a photoreducible benzoxanthene or benzothioxanthene dye, and (d) a second photoinitiator comprising a trihalomethyl compound capable of being cleaved by irradiation. The mixture is suitable for the production of printing plates and photoresists and displays increased photosensitivity.

Abstract: A process for the addition of compounds containing silicon-bonded hydrogen to compounds containing aliphatic unsaturation and compositions suitable for said process. The process is activated by visible radiation and is conducted in the presence of a platinum complex having one cyclopentadienyl group that is eta-bonded to the platinum atom and three aliphatic groups that are sigma-bonded to the platinum atom and a sensitizer that is capable of absorbing visible light and is capable of transferring energy to said platinum complex such that the hydrosilation reaction is initiated upon exposure to visible light. The invention also provides for use in the aforementioned process.

Abstract: Disclosed herein are novel diesters of (meth)acrylic acid represented by the following formula: ##STR1## wherein the mean values of m and n are respectively 0 to 5, preferably 0 to 3, the mean value of m+n is 1 to 10, preferably 1 to 6, and R represents H or CH.sub.3.Also, disclosed herein are resin compositions comprising said diester(s) of (meth)acrylic acid, polyurethane (meth)acrylate(s), monoethylenically unsaturated monomer(s) and initiator(s) of photopolymerization as an optional component.

Abstract: The invention provides thioxanthone derivatives of general formula ##STR1## wherein one of R.sup.2, R.sup.3 and R.sup.4 is a group of formula ##STR2## in which one of R.sup.5, R.sup.6 and R.sup.7 is an alkyl or a benzyl group, the others being alkyl groups and A.sup.- represents an anion, and R.sup.1 and the others of R.sup.2, R.sup.3, and R.sup.4 are independently selected from hydrogen atoms, alkyl groups and alkoxy groups; and the use of such derivatives as photoinitiators, particularly in aqueous photopolymerizable compositions for the production of stencils for screen printing.

Abstract: A linear polymer having a recurring unit represented by the formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each independently is a hydrogen atom, a C.sub.1-10 alkyl group, a C.sub.6-10 cycloalkyl group, an aryl group, or a halogen atom and the ethynyl group is in either meta position or para position to the main polymer chain;and a weight-average molecular weight of 1,000 to 1,000,000. A resin composition consisting essentially of (i) a polymer having a recurring unit represented by the formula (I) or a polymer having a recurring unit represented by the formula (I) and a recurring unit represented by the formula (II): ##STR2## wherein X and Y each independently is a C.sub.6-20 aryl group, a C.sub.1-10 alkyl group, a C.sub.6-10 cycloalkyl group, a silyl group having a C.sub.1-10 alkyl group or a C.sub.

Abstract: The curable organopolysiloxane composition of the invention is formulated with two kinds of crosslinking agents including an organosilane compound having 2 or 3 isopropenyloxy groups in a molecule and an organopolysiloxane having at least 2 mercapto groups in a molecule added to the base ingredient of a hydroxy-terminated diorganopolysiloxane together with a curing catalyst and a photosensitizer. The composition has two-way curability by the condensation reaction in the presence of atmospheric moisture between the silanolic hydroxy groups and the isopropenyloxy groups and by the ultraviolet-induced addition reaction between the isopropenyloxy groups and the mercapto groups to exhibit very reliable curing behavior giving a cured rubbery elastomer having excellent properties.

Abstract: This invention describes UV-stabilized step growth polymers such as polyesters, polyurethanes, polycarbonates, and combinations thereof. The UV-stabilizing moieties present in these polymers comprise chemically bound, pendant ortho-hydroxydiphenyl ketone based moieties. The polymers are especially useful as protective films and fibers which are highly resistant to ultraviolet (UV) and sunlight degradation.

Abstract: Novel compositions of matter which crosslink under the action of light and which contain(A) an aliphatically unsaturated polymerization product which is free of aromatic groups and which can contain structural elements of the formula I ##STR1## (B) a bisimide of the formula II ##STR2## and a sensitizer and, if desired, a further crosslinking agent, where R and R' are alkyl or together are tetramethylene, R.sub.1 is hydrogen, chlorine or methyl, Y and Y' are each --OH or together are --O-- and R.sub.4 is alkylene, arylene or bis-arylene, are suitable, inter alia, for preparing printing plates or as photoresist materials.

Abstract: A method for preparing a compound of formula I ##STR1## in which X is O or S;both groups R together with the two carbon atoms to which they are attached form a fused aromatic group;R.sub.1 is an organic radical; andn is 0, 1, 2 or 3comprising reacting a compound of formula II ##STR2## where R, R.sub.1 and n are defined above and where each R.sub.3, independently, is C.sub.1-12 alkoxy or one R.sub.3 is C.sub.1-12 alkoxy and the other R.sub.3 is halogen,with elemental sulphur in an alkaline medium, a metal sulphide or a metal hydrosulphide.Compounds of formula I and formula II are useful as photoinitiators.

Abstract: A process is disclosed for producing an abrasion resistant UV curable photopolymerizable composition for coating substrates. The process involves dense grafting and comprises hydrolyzing in an aqueous acidic solution a trialkoxysilane to render it organophillic followed by dispersion with fine silica or alumina. Grafting of the hydrolyzed trialkoxysilane to the silica or alumina is effected through dehydration. The grafted material is then dispersed into intimate contact with one or more photopolymerizable monomers and photoinitiators.

Abstract: Novel compositions of matter which crosslink under the action of light and which contain(A) an aliphatically unsaturated polycondensation product which can contain structural elements of the formula I ##STR1## (B) a bisimide of the formula II ##STR2## and a sensitizer and can, if desired, also contain a further crosslinking agent, where R, R', R.sub.1, Y, Y' and R.sub.4 are as defined in claim 1, are suitable, inter alia, for preparing printing plates or for use as photoresist materials.