Abstract: This invention relates to a radiation curable silicone coating composition comprising an alkoxylated resin-polymer organosilicone network containing radiation curable functionality and a cationic photoinitiator. The radiation curable silicone compositions of this invention are useful as fast curing low and high release coating compositions which are especially suitable for release of pressure sensitive adhesives.

Abstract: Photocurable, addition polymerizable compositions contain an epoxy resin and a photoinitiator system containing (a) an epoxy resin, (b) a hydroxyl containing material and (c) a photoinitiator system comprising: (i) an iodonium salt; (ii) a visible light sensitizer; and (iii) an electron donor compound, wherein the photoinitiator system has a photoinduced potential of at least about 100 mV relative to a standard solution of 2.9×10−5 moles/g diphenyl iodonium hexafluoroantimonate and 1.5×10−5 moles/g camphorquinone in 2-butanone. The compositions cure on exposure to light in the visible spectrum and are useful in a variety of applications, including dental adhesives and composites.

Abstract: Photopolymerizable compositions that include free radically active and cationically active functional groups, and methods for polymerizing such compositions, in which the onset of cationic polymerization is controllably delayed to extend the time between formation of a moldable gel and formation of a hardened solid.

Abstract: A photopolymerizable composition comprising i) an addition polymerizable compound having an ethylenically unsaturated double bond, ii) a sensitizing dye represented by the following formula (I) and iii) a titanocene compound: ##STR1## wherein A.sup.1 and A.sup.2 each represents a carbon atom or a hetero atom, Q.sup.1 represents a nonmetallic atom group necessary for forming a heterocyclic ring together with A.sup.1, A.sup.2 and the carbon atoms adjacent thereto, R.sup.1 and R.sup.2 each represents a hydrogen atom, an alkyl group or an aryl group and R.sup.1 and R.sup.2 may be combined with each other to form a ring, X.sup.1 and X.sup.2 each represents a cyano group or a substituted carbonyl group and X.sup.2 and X.sup.2 may be combined with each other to form a ring, and n represents 0, 1 or 2.

Abstract: Process for forming a selectively colored polymeric layer, or a three-dimensional article made of polymeric layers, wherein a photocurable, photocolorable composition is irradiated with a low dose of light to cure and a different, preferably higher, dose of light to color. The process is particularly useful for preparing selectively colored ornamental and industrial articles and models of plant and animal parts, especially medical models.

Abstract: A novel photo-curable resin composition. The resin composition capable of providing a cured product having excellent mechanical strength, high dimensional accuracy, and excellent toughness. The resin composition is capable of providing a cured product which experiences little change in mechanical strength over time. The resin composition is capable of forming, by photo-fabricating, a three-dimensional object which can be used for a long period of time in a humid atmosphere. The composition comprises, (A) an epoxy compound having a cyclohexene oxide, (B) a cationic photo-initiator, (C) an ethylenically unsaturated monomer, (D) a radical photo-initiator, and (E) a polyol.

Abstract: Curable reaction resin mixtures which are suitable for stereolithography have the following composition:a cationically curable monomer and/or oligomer,an initiator with the following structure: ##STR1## where the following applies: R.sup.1 and R.sup.2 are alkyl or cycloalkyl, or together with the S atom they form a heterocyclic ring,R.sup.3 is H or alkyl,R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are H, alkyl or alkoxy,X.sup.- is a non-nucleophilic anion,and optionally a filler, pigment and/or additive.

Abstract: Dye compounds of the formula ##STR1## wherein X is for example CH, C--CH.sub.3 or .sup.+ NOR L.sup.- ; R is inter alia C.sub.1 -C.sub.6 alkyl; R.sub.1 is for example C.sub.1 -C.sub.8 alkoxy or C.sub.1 -C.sub.12 alkyl; s is 0 to 4; R.sub.2 is for example hydrogen; Ar is for example a group ##STR2## Y inter alia is C.sub.1 -C.sub.6 alkyl or C.sub.1 -C.sub.6 alkoxy; r in the formula (A) is 0 to 5, in the formulae (B) and (E) is 0 to 9 and in the formula (D) is 0 to 7; and L is an anion;in combination with an electron donor compound, especially a borate compound, are suitable as photoinitiators for the photopolymerization of radically polymerizable compositions.

Abstract: Compounds of formula (I), ##STR1## wherein X is CH, C--CH.sub.3, C--Cl, C--O--C.sub.1 -C.sub.8 alkyl or N; R is C.sub.1 -C.sub.6 alkyl, benzyl, CH.sub.2 COOR.sub.3 or a group (a); R.sub.1 is C.sub.1 -C.sub.8 alkoxy, C.sub.1 -C.sub.12 alkyl, halogen, NO.sub.2, benzyloxy or phenyloxy, wherein the phenyl ring in the benzyloxy or phenyloxy group is unsubstituted or substituted by C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.12 alkyl, halogen or CF.sub.3 ; R.sub.2 is C.sub.1 -C.sub.8 alkoxy, C.sub.1 -C.sub.12 alkyl, benzyloxy or phenyloxy, wherein the phenyl ring in the benzyloxy or phenyloxy group is unsubstituted or substituted by C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.12 alkyl, halogen or CF.sub.3 ; R.sub.3 is hydrogen, C.sub.1 -C.sub.12 alkyl or benzyl; Y is unsubstituted or C.sub.1 -C.sub.6 alkoxy-substituted C.sub.1 -C.sub.6 alkyl, or Y is C.sub.1 -C.sub.6 alkoxy, halogen, CF.sub.3, NO.sub.2, benzyloxy or phenyloxy, wherein the phenyl ring in the benzyloxy or phenyloxy group is unsubstituted or substituted by C.

Abstract: A visible radiation sensitive composition is described which comprises a binder, one or more polymerizable compounds containing at least one polymerizable group, and one or more dyes having an absorption range in the emission range of the radiation source, characterized in that said composition comprises as an initiator an initiator system consisting of a metallocene as a photoinitiator and an onium compound as a coinitiator. The visible radiation sensitive composition shows an increased radiation sensitivity compared to the known radiation sensitive compositions and is especially suitable for recording materials such as printing plates, which can, in particular, also be exposed by means of laser radiation in the visible range.

Abstract: Photocurable, addition polymerizable compositions contain an epoxy resin and a photoinitiator system containing (a) an epoxy resin and (b) a photoinitiator system comprising: (i) an iodonium salt; (ii) a visible light sensitizer; and (iii) an electron donor compound, wherein the photoinitiator system has a photoinduced potential of at least about 0 mV relative to a standard solution of 2.9.times.10.sup.-5 moles/g diphenyl iodonium hexafluoroantimonate and 1.5.times.10.sup.-5 moles/g camphorquinone in 2-butanone. The compositions cure on exposure to light in the visible spectrum and are useful in a variety of applications, including dental adhesives and composites.

Abstract: This invention relates to a radiation curable silicone compositions. More particularly this invention relates to radiation curable silicone compositions comprising a vinyl ether functional silicon compound, a cationic photoinitiator, a free radical photoinitiator, and dodecylphenol. The compositions of this invention can further comprise a vinyl ether compound which is free of silicon atoms. The radiation curable silicone compositions of this invention are useful as release coating compositions which are especially suitable for release of pressure sensitive adhesives.

Abstract: This invention relates to a radiation curable compositions. More particularly this invention relates to radiation curable compositions comprising a vinyl ether compound which is free of silicon atoms, a cationic photoinitiator, a free radical photoinitiator, and dodecylphenol. The radiation curable compositions of this invention are useful for coating a thin layer film that has potential for many applications in the coating industry.

Abstract: Photocurable, addition polymerizable compositions contain an epoxy resin and a photoinitiator system containing (a) an epoxy resin and (b) a photoinitiator system comprising: (i) an iodonium salt; (ii) a visible light sensitizer; and (iii) an electron donor compound, wherein the photoinitiator system has a photoinduced potential of at least about 0 mV relative to a standard solution of 2.9.times.10.sup.-5 moles/g diphenyl iodonium hexafluoroantimonate and 1.5.times.10.sup.-5 moles/g camphorquinone in 2-butanone. The compositions cure on exposure to light in the visible spectrum and are useful in a variety of applications, including dental adhesives and composites.

Abstract: Compounds of the formulae I, II, III and IV ##STR1## wherein Ar for example is a phenyl, biphenyl or benzoylphenyl group, which is unsubstituted or substituted; Ar.sub.1, for example, has the same meanings as Ar; Ar.sub.2 is inter alia phenyl; X may be a direct bond; Y hydrogen, etc.; R.sub.1 and R.sub.2 for example C.sub.1 -C.sub.8 alkyl; R.sub.3 inter alia hydrogen or C.sub.1 -C.sub.12 alkyl; R.sub.4 is inter alia C.sub.1 -C.sub.12 alkyl; or R.sub.3 and R.sub.4 together are C.sub.3 -C.sub.7 alkylene; R.sub.5 is for example C.sub.1 -C.sub.6 alkylene; and Z is a divalent radical; provided that at least one of the radicals Ar, Ar.sub.1, Ar.sub.2, Ar.sub.3, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 or Y is substituted by 1 to 5 SH groups, or provided that Y contains at least one --SS-- group, are photoinitiators for the polymerization of ethylenically unsaturated compounds.

Abstract: Photocurable addition-polymerizable compositions containing a free-radically-polymerizable monomer and a photoinitiator system containing i) an arylidonium salt, ii) a sensitizing compound, and iii) an electron donor having an oxidation potential that is greater than zero and less than or equal to that of p-dimethyoxybenzene (1.32 volts vs. S.C.E.). The compositions cure rapidly and deeply under ultraviolet or visible light.

Abstract: The present invention provides a thermosetting organic solvent type coating capable of forming a cured coating film having a TUKON hardness at 20.degree. C. of 15 or more and the minimum value of dynamic modulus E' at a frequency of 110 Hz in the temperature range of 150-200.degree. C., of 1.times.1O.sup.9 dyn/cm.sup.2 or more. The cured film formed from the coating, as compared with the cured films formed from conventional organic solvent type coatings used as a top coat for automobile (e.g. an organic solvent type coating containing, as main components, a hydroxyl group-containing acrylic resin and a melamine resin, or a carboxylic-epoxy type coating), is at least equivalent in weatherability, finish appearance, acid resistance, etc. and superior in stain resistance.

Abstract: A radiation curable release coating composition comprising, by weight,(a) 10-90% of an acrylate-functional silicone resin,(b) 10-90% of a vinylether monomer as reactive diluent therein, and(c) a photoinitiator.

Abstract: An ionic compound comprising at least one group A.sup.+ X.sup.-, comprising:a cationic group A.sup.+ selected from the group consisting of biaryliodonium, arylsulfonium, arylacylsulfonium, diazonium and organometallic cations comprising a transition metal complexed with at least one unsaturated cyclic compound comprising 4-12 carbon atoms, said cationic group being part of a polymer chain; whereinX.sup.- is an imide anion, [FSO.sub.2 NSO.sub.2 R'.sub.F ].sup.- or [R.sub.F CH.sub.2 OSO.sub.2 NSO.sub.2 R'.sub.F ].sup.- or [(R.sub.F).sub.2 CHOSO.sub.2 NSO.sub.2 R'.sub.F ].sup.-, or a methylide anion [FSO.sub.2 C(Q)SO.sub.2 R'.sub.F ].sup.-, or a [R.sub.F CH.sub.2 OSO.sub.2 C(Q)SO.sub.2 R'.sub.F ].sup.- or [(R.sub.F).sub.2 CHOSO.sub.2 C(Q)SO.sub.2 R'.sub.F ].sup.31 .

Abstract: Photocurable, addition polymerizable compositions contain an epoxy resin and a photoinitiator system containing (a) an epoxy resin, (b) a hydroxyl containing material and (c) a photoinitiator system comprising: (i) an iodonium salt; (ii) a visible light sensitizer; and (iii) an electron donor compound, wherein the photoinitiator system has a photoinduced potential of at least about 100 mV relative to a standard solution of 2.9.times.10.sup.-5 moles/g diphenyl iodonium hexafluoroantimonate and 1.5.times.10.sup.-5 moles/g camphorquinone in 2-butanone. The compositions cure on exposure to light in the visible spectrum and are useful in a variety of applications, including dental adhesives and composites.

Abstract: A liquid, radiation-curable composition which in addition to a liquid, free-radically polymerizable component comprises at least the following additional components: (A) from 40 to 80 percent by weight of a liquid difunctional or more highly functional epoxy resin or of a liquid mixture consisting of difunctional or more highly functional epoxy resins; (B) from 0.1 to 10 percent by weight of a cationic photoinitiator or of a mixture of cationic photoinitiators; and (C) from 0.

Abstract: A method for the formation of a colored polymeric body which comprises subjecting a curable composition containing a color precursor and an onium salt to heat or actinic radiation to cure the composition, wherein the color precursor is converted to its colored form, and a curable composition capable of forming a colored polymeric body, are disclosed.

Abstract: The present invention relates to novel compositions that contain an activator system that comprises a photoactivator, acid generator and chain extender. Methods and articles of manufacture that comprise such compositions are also provided. In a preferred aspect, the compositions are photoimageable.

Abstract: The invention provides a novel sulfonium salt having at least one acid labile group attached to a phenyl group in a molecule and a normal, branched or cyclic C.sub.1 -C.sub.20 alkylsulfonate anion. The novel sulfonium salt is effective for increasing the dissolution contrast between exposed and unexposed areas. Upon exposure, it generates an alkylsulfonic acid which is a weak acid, minimizing the influence of side reaction and deactivation during PEB step. The sulfonium salt is useful in a chemically amplified positive resist composition which lends itself to fine patterning and features high resolution.

Abstract: A styrylcoumarin compound jointing a styryl group by--(C.dbd.C)n--portion and having --NR.sub.1 R.sub.2 group, wherein n is an integer of 2 to 4, and each R is a proton or an alkyl group having 1 to 10 carbon atoms. A photopolymerizable composition comprises the styrylcoumarin compound as a photosensitizer, a polymerization initiator and a polymerizable compound. A photocrosslinking composition comprises the styrylcoumarin compound as a photosensitizer, a crosslinking agent and a polymerizable compound. A volume phase hologram recording medium which comprises the styrylcoumarin compound, a crosslinking agent and a polymer comprising a carbazole.

Abstract: A visible-light photopolymerizable composition comprising a) a cationically polymerizable epoxy resin, b) a hydroxyl-containing material c) an aryliodonium salt and d) a visible light sensitizer that is an alpha-dicarbonyl compound having an extinction coefficient less than about 1000. Particularly preferred compositions of the present invention are dental materials.

Abstract: Compounds of the formulaRG--A--INwherein IN is a photoinitiator basic structure A is a spacer group and RG is a functional reactive group can be employed as coreactive photoinitiators for photo-polymerization of systems containing ethylenically unsaturated compounds.

Abstract: Compositions containing conductivity enhancers, which are capable of being coated onto a substrate by means of electrostatic assistance. The compositions comprise one or more free-radically curable monomer(s), and one or more non-volatile conductivity enhancer(s), having cationic and anionic portions, which are soluble in the monomer(s) and which do not interfere with free-radical polymerization, wherein said anionic portion is a non-coordinating organophilic carbon-containing anion. The compositions may further comprise one or more initiator(s), one or more dissociation enhancing agent(s), cross-linking agent(s), cationically polymerizable monomer(s), cationic initiator(s), leveling agents, oligomer(s) or polymer(s), preferably co-reactive, and other additives or adjuvants to impart specific properties to the cured coating.

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: The present invention is directed to sulfonium salt-containing compounds represented by a following general formula; ##STR1## wherein R.sub.1 is alkyl containing from 1 to 18 carbon atoms, hydroxy, alkoxy containing from 1 to 18 carbon atoms, alkylcarbonyloxy containing from 1 to 18 carbon atoms or halogen, n is any of 0, 1, 2 or 3, however, each of R.sub.1 may be different from the others when n is 2 or more, R.sub.2 is alkyl containing from 1 to 6 carbon atoms, R.sub.3 and R.sub.4 are each independently hydrogen or alkyl containing from 1 to 6 carbon atoms, R.sub.5 and R.sub.6 are each independently hydrogen, alkyl containing from 1 to 6 carbon atoms, hydroxy, alkoxy containing from 1 to 6 carbon atoms, alkylcarbonyloxy containing from 1 to 18 carbon atoms or aromatic carbonyloxy, and R.sub.7 is alkyl containing from 4 to 20 carbon atoms or a group represented by a following formula; ##STR2## wherein R.sub.

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: A photosensitive resin composition comprising the following components (A), (B) and (C): (A) a photopolymerizable urethane (meth)acrylate compound containing at least two acryloyl or methacryloyl groups, (B) an alkali-soluble polymer compound having an acid value of from 50 to 250 mgKOH/g, and (C) a photopolymerization initiator, wherein the photosensitive resin composition has an electrical insulation resistance of 8.0.times.10.sup.9 to 1.0.times.1.0.sup.14 .OMEGA..multidot.cm after photocuring. A photosensitive resin laminated film comprising a flexible film, a photosensitive layer provided on the flexible film, and a releasable film layer provided on the photosensitive layer, wherein the photosensitive layer comprises the above photosensitive resin composition.

Abstract: The present invention relates to a radiation curable silicone release coating composition comprising (A) an alicyclic epoxy-functional silicone graft copolymer, (B) an organic compound having at least 2 alicyclic epoxy groups, and (C) a photocuring catalyst. The compositions of this invention are highly adhesive to a variety of substrates, have excellent coatability, and the release resistance values of films having the composition of this invention cured thereon can be adjusted over a wide range of values.

Abstract: A photopolymerizable composition is described, comprising components (i) a compound having at least one addition-polymerizable ethylenically unsaturated bond, (ii) a compound represented by the following formula (I): ##STR1## and (iii) an activating agent which generates an active radical upon light irradiation in the co-presence of component (ii). The substituents in formula (I) are defined in the specification.

Abstract: The invention provides a novel polysiloxane compound, typically polyhydroxybenzylsilsesquioxane, having some hydroxyl groups replaced by acetal groups and optionally acid labile groups. The polysiloxane compound is useful as an alkali soluble polymer for positive resist material.

Abstract: The invention provides a photosensitive resin composition useful as a photoresist of chemical amplification type for deep UV lithography such as ArF excimer laser lithography. The resin composition contains, as an acid generator, an alkylsulfonium salt of the general formula (I), wherein R.sup.1 is a C.sub.7 to C.sub.12 alkyl having a bridged alicyclic structure or a C.sub.5 to C.sub.7 monocyclic alkyl, R.sup.2 is an alkyl, R.sup.3 is a C.sub.5 to C.sub.7 .beta.-oxomonocyclic alkyl or a C.sub.7 to C.sub.10 bridged cyclic alkyl having oxo group at the .beta.-position. The general formula (I) is inclusive of novel alkylsulfonium salts in which R.sup.1 is norbornyl group, adamantyl group or cyclohexyl group, R.sup.2 is methyl group and R.sup.3 is .beta.-oxocyclohexyl group or .beta.-oxonorbornane-2-yl group.

Abstract: A combination of a photoacid precursor and sensitizer for use with multiple wavelengths of an argon ion laser.

Abstract: Disclosed is a photosensitive composition for volume hologram recording which is used for recording an interference fringe produced by a laser beam or a light having excellent coherence, as fringes having different refractive index. The composition comprising:(a) a cationic polymerizable compound which is liquid at ambient temperature;(b) a radical polymerizable compound;(c) a radical photopolymerization initiator composition sensitized by a laser beam or a light having excellent coherence which has a specific wavelength to polymerize the ingredient (b); and(d) a cationic photopolymerization initiator composition which shows low photosensitivity to the light having a specific wavelength and is sensitized by a light having the other wavelength to polymerize the ingredient (a), wherein an average refractive index of the ingredient (a) is smaller than that of the ingredient (b). A process for producing the photosensitive composition is also disclosed.

Abstract: A high-performance composite reinforcing material for optical fiber cables, exhibiting excellent protective effect when incorporated into a reinforcing component of optical fiber cables, and having a degree of flexibility applicable to curved wiring of a small radius of curvature.

Abstract: A chemically amplified, positive resist composition contains a trifluoromethanesulfonic or p-toluenesulfonic acid bis- or tris(p-tert-butoxyphenyl)sulfonium salt and a nitrogenous compound. The composition is highly sensitive to high energy radiation, especially KrF excimer laser and has high sensitivity, resolution and plasma etching resistance while the resulting resist pattern is heat resistant.

Abstract: A photosensitive composition containing a curable cyanate ester and a cationic photoinitiator; and use thereof to form a resist image.

Abstract: Photocurable addition-polymerizable compositions containing a free-radically-polymerizable monomer and a photoinitiator system containing i) an arylidonium salt, ii) a sensitizing compound, and iii) an electron donor having an oxidation potential that is greater than zero and less than or equal to that of p-dimethyoxybenzene (1.32 volts vs. S.C.E.). The compositions cure rapidly and deeply under ultraviolet or visible light.

Abstract: An active energy ray-curing resin composition comprises (i) a graft copolymerized polymer, (iii) an epoxy resin comprising at least one compound having one or more epoxy groups in the molecule and (iv) a polymerization initiator capable of generating a Lewis acid by irradiation of an active energy ray.

Abstract: The composition of the present invention is excellent in compatibility, transparency and curability and give a cured coat of excellent gloss and of less smell, and cured products of excellent properties can be obtained by curing the composition.The present invention relates to an onium salt represented by the following formula (1): ##STR1## wherein Ar is a mono- to tetra-valent aromatic group, X is a bisphenylsulfonio group which may have a substituent, a is 1-4, b is 0 or 1-3, a+b is 1-4, n is 1-4, and Z is a halide represented by the following formula (3): ##STR2## where M is a boron atom, a phosphorus atom, an arsenic atom or an antimony atom, Q is a halogen atom, m is 3-6, l is 0 or 1, and m+l is 4-6; a photopolymerization initiator containing the onium salt as an active ingredient; an energy ray-curable composition containing the initiator; and a cured product.

Abstract: The present invention relates to a resin composition for optical molding which comprises (a) an actinic radical-curable and cationically polymerizable organic substance and (b) an actinic radiation-sensitive initiator for cationic polymerization. This composition can be cured without being affected by atmospheric oxygen.

Abstract: This invention relates to vinyl ether-based coatings for which properties such as color stability, thermal stability, mechanical stability, hydrolyric stability, and resistance to embrittlement may be maintained and properties hydrogen generation and blocking are minimized. The invention also relates to stabilizers which control these properties in the coatings.

Abstract: The composition of the present invention is excellent in compatibility, transparency and curability and give a cured coat of excellent gloss and of less smell, and cured products of excellent properties can be obtained by curing the composition.The present invention relates to an onium salt represented by the following formula (1): ##STR1## wherein Ar is a mono- to tetra-valent aromatic group, X is a bisphenylsulfonio group which may have a substituent, a is 1-4, b is 0 or 1-3, a+b is 1-4, n is 1-4, and Z is a halide represented by the following formula (3):MQ.sub.m (OH).sub.l (3)where M is a boron atom, a phosphorus atom, an arsenic atom or an antimony atom, Q is a halogen atom, m is 3-6, l is 0 or 1, and m+l is 4-6; a photopolymerization initiator containing the onium salt as an active ingredient; an energy ray-curable composition containing the initiator; and a cured product.

Abstract: The present invention relates to an improved chemically amplified photoresist composition comprising (i) a photosensitive acid generator and (ii) a polymer comprising the reaction product of hydroxystyrene with acrylate, methacrylate or a mixture of acrylate and methacrylate.

Abstract: A polymerizable composition comprising:(a) a monomer; and(b) a sulfinate represented by the formula (I): ##STR1## wherein R.sup.1 and R.sup.5 each represents a substituent having 2 to 6 carbon atoms, R.sup.2, R.sup.3 and R.sup.4 each represents an atom or substituent inert to the monomer (a), M.sup.n+ represents a n-valent cation, and n represents an integer of 1 to 4.

Abstract: A radiation-crosslinkable mixture which contains a carboxyl-containing precursor of a heterocyclic polymer, a copolymerizable ethylenically unsaturated ternary sulfonium salt, a photoinitiator and a polar aprotic organic solvent.