Abstract: Disclosed are organopolysiloxane preparations containing: A) units of the formula (I): (R.sup.1 O).sub.a SiHR.sup.2.sub.2-a O1/2, in which R.sup.1 and R.sup.2, which may be the same or different, are each, independently of each other, an optionally substituted monovalent hydrocarbon group and a is 1 or 2, B) siloxane units which can be cross-linked by irradiating and, optionally, C) siloxane units acting as photo-initiators. These preparations are useful for the production of coatings.

Abstract: The surface of a polymer such as polypropylene, may be treated by contact with an amine donor such as ethylene diamine followed by irradiation with ultraviolet light of wave length of about 1800.ANG.-2800.ANG. to improve surface wettability.

Abstract: A novel initiator for photopolymerization is provided, which can polymerize cationically polymerizable organic material by only irradiating at wavelength of 200-500 nm without specific sensitizer and/or post-curing even when it is used at comparatively small amount, whereby the obtained cured product has good physical properties and electric properties.The initiator for photopolymerization of cationically polymerizable organic material according to the present invention comprises a composite obtainable from a reaction between (a) charge transfer complex consisting of biscyclopentadienyl iron derivative and quinoid and (b) at least one salt selected from a group consisting of tetrafluoroborates, hexafluorophosphates and hexafluoroantimonates.

Abstract: Energy polymerizable compositions comprising at least one cyanate monomer and as curing agent an organometallic compound are disclosed. The compositions are useful in applications requiring high performance, such as high temperature performance; in composites, particularly structural composities; structural adhesives; tooling for structural composities; electronic applications such as printed wiring boards and semiconductor encapsulants; graphic arts; injection molding and prepregs; and high performance binders.

Abstract: An energy polymerizable composition and process therefore, comprising a cationically polymerizable material and a catalytically effective amount of an ionic salt of an organometallic complex cation as polymerization initiator, said ionic salt of an organometallic complex cation being capable of adding an intermediate strength nucleophile or upon photolysis capable of liberating at least one coordination site, said metal in said organometallic complex cation being selected from elements of Periodic Groups IVB, VB, VIB, VIIB, and VIIIB are disclosed. Certain of the organometallic metallic polymerization initiators are novel cationic salts.

Abstract: A radiation-curable coating composition for ophthalmic lens is disclosed which comprises a mixture of a monoepoxysilane, colloidal silica, an alkylalkoxysilane or tetraalkoxysilane, and an ultraviolet activated photoinitiator capable of initiating a cationic cure of such composition. The photoinitiator is an aromatic onium salt or an iron arene salt complex.

Abstract: Compounds of the formula I are described[R.sup.1 (Fe.sup.II R.sup.2 .sub.a ].sub.q.sup.+an anX.sup.-q (I)in which a is 1 or 2, n is 1 or 2, R.sup.1 is a substituted or unsubstituted .pi.-arene, R.sup.2 is a substituted or unsubstituted .pi.-arene or cyclopentadienyl anion or indenyl anion, q is an integer from 1 to 3, and X is FSO.sup.-.sub.3 or a q-valent anion of an organic sulfonic acid or of a carbocyclic acid; R.sup.1 can also be a polymeric, aromatic ligand. The invetion particularly relates to the compounds of the formula I wherein a is 1 and q is 1 and X.sup.

Abstract: An anisotropically conductive adhesive composition provides electrical conductivity between facing electrodes but maintains electric insulation laterally between adjacent electrodes and comprises (a) a cationically polymerizable monomer, such as a glycidyl epoxy resin; (b) a thermoplastic resin, essentially free of nucleophilic or metal complexing functional groups; (c) optionally, an alcohol containing material; (d) a thermally initiated catalyst system comprising: (1) a salt of an organometallic cation; (2) a cure rate enhancer; and (3) a stabilizing additive; (e) conductive particles; and (f) optionally, a silane coupling agent, wherein the adhesive compositions cure at a temperature of 120.degree.-125.degree. C.

Abstract: A keto arene-cyclopentadienyl iron complex salt of the formula:[(R.sup.2 CO)(R.sup.1).sub.m C.sub.6 H.sub.5--m Fe.sup.II Cp].sup.+1 A.sup.-1wherein R.sup.1 is an alkyl group, R.sup.2 is an alkyl group or phenyl group, m is an integer of 1 to 5, Cp is an .eta..sup.5 -cyclopentadienyl group and A.sup.-1 is a non-nucleophilic anion, e.g. pentamethylacetophenone-Fe(II)-Cp.sup.+ PF.sub.6.sup.-1 salt or pentamethylbenzophenone-Fe(II)-Cp.sup.+ PF.sub.6.sup.-1 salt, which is useful as a photoinitiator for cationically polymerizable compounds, especially for epoxy resins, and has an improved environmental safety and a high absorptivity, and which can be easily produced by a direct replacement reaction between dicarbonyl-.eta..sup.5 -(2,4-cyclopentadien-1-yl)iron(II) halide and an alkyl substituted keto arene to be replaced for the carbonyl ligands.

Abstract: Cationically crosslinkable polyorganosiloxane compositions, well suited for providing antiadhesive coatings on a wide variety of shaped substrates via the photochemical/electron beam crosslinking thereof, include a catalytically effective amount of an onium borate of an element of Groups 15 to 17 of the Periodic Table, the anionic borate moiety of which onium borate 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 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: Fluorine-free titanocene compounds of the formula I or II ##STR1## in which both R.sub.1 radicals are preferably, independently of one another, cyclopentadienyl.sup..crclbar., which is unsubstituted or substituted by alkyl,alkoxy or --Si(R.sub.2).sub.3, and both R.sub.2 radicals are, in particular, alkyl, ##STR2## Z is --NR.sub.10 --, --0-- or --S--, Y is Cl, Br, I, CN, SCN, --O--CO--CH.sub.3, --O--CO--phenyl or --O--SO.sub.2 --CH.sub.3,n is 1 or 2,m is 0 or 1, where the sum of n and m must be 2,R.sub.3, R.sub.4 and R.sub.5 are in particular, independently of one another, hydrogen, Cl, alkyl, cycloalkyl, adamantyl, phenyl, pyrryl or biphenylyl, where these radicals are unsubstituted or substituted by alkyl, Cl, alkylthio, --NR.sub.8 R.sub.9, phenyl, phenylthio or C.sub.1 -C.sub.10 alkoxy, or R.sub.3, R.sub.4 and R.sub.5 are alkenyl, alkoxy, cycloalkoxy, phenoxy, benzyloxy, tetrahydrofurfuryloxy, alkylthio, cycloalkylthio, benzylthio or phenylthio, where R.sub.3 and R.sub.

Abstract: A novel siloxane polymer having at least 1 mol % of a structural unit derived from a cyclic heat addition product between a diene compound of formula (I) or (II) and an olefin or acetylene compound of formula (III), (IV) or (V): ##STR1## and a positive working light-sensitive composition comprising the siloxane polymer.

Abstract: Organosilicon compounds with a siloxane portion and groups of the general formula --OR'OCH.dbd.CHR" (i) linked via an Si--O--C bond, wherein R' is a divalent hydrocarbon radical or a group --R.degree.--(OR.degree.).sub.n --, wherein R.degree. is alkylene and n is from 1 to 12, R" is H or alkyl are useful in radiation curable compositions, in which they are mixed with an initiator. The compositions are particularly useful in UV radiation curable relase coatings.

Abstract: Titanocenes of the formula I ##STR1## in which R.sup.1 are cyclopentadienyl.sup..crclbar. groups and R.sup.2 and R.sup.3 are aromatic radicals which are substituted in both ortho-positions by fluorine and, in addition, are substituted by an acyloxy group are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds.

Abstract: This invention relates to production of a super long conjugated polymer to be used for a molecular device, etc. According to this invention, an acetylene derivative is previously oriented and formed into a monomolecular film on the surface of a substrate and its acetylenic group is polymerized by a catalyst or by irradiation of an energy beam while keeping the orientation. Since the respective molecules are oriented and aligned on the substrate surface, the polymerization reaction readily proceeds, and after the polymerization the resulting polyacetylene molecules are prevented from the breakage of conjugated bonds caused by thermal agitation or twisting of the polyacetylene molecules. Accordingly, a polyacetylene or polyacene type polymer having long conjugated bonds can be obtained easily.

Abstract: This invention relates to production of a super long conjugated polymer to be used for a molecular device, etc. According to this invention, an acetylene derivative is previously oriented and formed into a monomolecular film on the surface of a substrate and its acetylenic group is polymerized by a catalyst or by irradiation of an energy beam while keeping the orientation. Since the respective molecules are oriented and aligned on the substrate surface, the polymerization reaction readily proceeds, and after the polymerization the resulting polyacetylene molecules are prevented from the breakage of conjugated bonds caused by thermal agitation or twisting of the polyacetylene molecules. Accordingly, a polyacetylene or polyacene type polymer having long conjugated bonds can be obtained easily.

Abstract: Liquid highly active photoinitiators are obtained by dissolving a solid photoinitiator of the titanocene type in liquid photoinitiators of the acetal or ketal type. The liquid mixtures have a long dark storage stability.

Abstract: Energy polymerizable compositions comprising at least one cyanate monomer and as curing agent an organometallic compound are disclosed. The compositions are useful in applications requiring high performance, such as high temperature performance; in composites, particularly structural composities; structural adhesives; tooling for structural composities; electronic applications such as printed wiring boards and semiconductor encapsulants; graphic arts; injection molding and prepregs; and high performance binders.

Abstract: A method of initiating oxygen scavenging by compositions which comprise oxidizable organic compounds and transition metal catalysts is disclosed. The method comprises initiating scavenging by exposing the composition, etc., to radiation. The radiation exposure is preferably electron beam or ultraviolet light and is preferably used on oxygen scavenging compositions which comprise a substituted or unsubstituted ethylenically unsaturated hydrocarbon and a transition metal catalyst. Inclusion of a photoinitiator or antioxidant in the scavenging composition is also preferred to facilitate and/or control the composition's scavenging properties. The method can be used for initiating scavenging in packaging layers or articles for oxygen sensitive products such as food and beverage.

Abstract: A dental adhesive comprising a (meth)acryloylaminoalkyl carboxylate of the formula ##STR1## in which R.sup.1 represents hydrogen or methyl;R.sup.2 represents methylene or ethylene; andR.sup.3 represents hydrogen, methyl, or ethyl;and at least one of an initiator, a non-toxic solvent, and a filler. The dental adhesive is useful to effect a strong adhesive bonding of dental materials to collagen-containing materials.

Abstract: Titanocenes of the formula I ##STR1## in which R.sup.1 are cyclopentadienyl.sup..crclbar. groups and R.sup.2 and R.sup.3 are aromatic radicals which are substituted in both ortho-positions by fluorine and, in addition, are substituted by an acyloxy group are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds.

Abstract: An improved stereolithography method for building a three-dimensional article including the steps of patternwise curing successive layers of a bath of curable liquid resin formulation until the article has been completely built up, removing the article from the liquid resin bath and then post-curing the article, wherein the liquid resin is a "thiol/nene" formulation including:(a) a first compound having a plurality of norbornene groups thereon;(b) a second compound having a plurality of thiol groups therein; and(c) a free radical photoinitiator,the total functionality of the formulation being greater than 4.

Abstract: A process for the actinic radiation-activated addition reaction of a compound containing silicon-bonded hydrogen with a compound containing aliphatic unsaturation, said addition being referred to as hydrosilation, comprising using, as a platinum hydrosilation catalyst, a complex represented by the formula: ##STR1## wherein R.sup.1 and R.sup.2 independently represent hydrogen, an alkyl group, or an aryl group, R.sup.3, R.sup.4, R.sup.5, and R.sup.6 independently represent an alkyl group, an aryl group, or an alkoxy group. The invention also includes novel compositions, capable of undergoing hydrosilation, containing the platinum complexes disclosed herein. An important application of the process and compositions of the invention is as a visible light curable impression material for dental applications.

Abstract: The present invention provides an adhesive composition that is useful as an energy-curable, one-part adhesive, suitable for bonding electronic components. The adhesive composition, preferably provided as an adhesive film, comprises the reaction product of an admixture of an effective amount of a curable cyanate ester resin, a thermoplastic polymer, and a curing catalyst. The catalyst may be, for example, thermally or photochemically activated.

Abstract: A photopolymerization initiator comprises a borate salt represented by the general formula (I):M.sup.n.sym. (B.sup..crclbar. R.sup.1 R.sup.2 R.sup.3 R.sup.4).sub.nwherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are respectively any one of halogen atoms, alkyl radicals, alkenyl radicals, alkynyl radicals, alicyclic radicals, aryl radicals, aryloxyl radicals, alkoxyl radicals, aralkyl radicals, and heterocyclic radicals, and may be the same with or different from each other; R.sup.1 and R.sup.2, or R.sup.2 and R.sup.3 may be linked to form a ring; M is an atom of a metal selected from Groups IB, IIB, IIIA, and IVA of the periodic table; and n is an integer of 1 or 2.A photosensitive composition comprises at least a polymerization compound and a photopolymerization initiator represented by the above general formula (I).

Abstract: The invention relates to an accelerated photoiniferter polymerization method which involves the addition of a polymerization accelerating amount of a at least one metal compound accelerator during the photoiniferter polymerization process.Preferably, the metal compound or compounds used are represented by the general formula M.sub.x L.sub.z whereinM is a cation having a valency of z of a metal which is selected from the group consisting of tin, zinc, cobalt, titanium, palladium, and lead;x is an integer of at least 1;L is an anion having a valency of x which is selected from the group consisting of C.sub.1-20 alkyl, -aryl, --OR, ##STR1## NO.sub.3.sup.--, SO.sub.4.sup..dbd., and PO.sub.4.sup.-3 ; R is selected from the group consisting C.sub.1-20 alkyl and aryl; andz is an integer of at least 1.Most preferably, the metal compound is selected from the group consisting of stannous 2-ethylhexanoate, zinc 2-ethylhexanoate and mixtures thereof.

Abstract: An energy polymerizable composition and process therefore, comprising a cationically polymerizable material and a catalytically effective amount of an ionic salt of an organometallic complex cation as polymerization initiator, said ionic salt of an organometallic complex cation being capable of adding an intermediate strength nucleophile or upon photolysis capable of liberating at least one coordination site, said metal in said organometallic complex cation being selected from elements of Periodic Groups IVB, VB, VIB, VIIB, and VIIIB are disclosed. Certain of the organometallic metallic polymerization initiators are novel cationic salts.

Abstract: A polymerizable composition comprises a polymeric precursor selected from the group consisting of 1) at least one ethylenically-unsaturated monomer, 2) at least one epoxy monomer, and 3) polyurethane precursors, and a curing agent comprising an organometallic compound and an onium salt.

Abstract: The present invention relates to a negative photoresist consisting essentially ofa) at least one solid film-forming polyphenol,b) at least one compound which contains at least two epoxide groups or at least two vinyl ether groups or at least one epoxide and vinyl ether group in the molecule,c) at least one cationic photoinitiator for component b) andd) if appropriate customary additives.The resist can be developed under aqueous-alkaline conditions.

Abstract: Iron (II)-aromatic compound complexes mixed with electron acceptors as an oxidizing agent are suitable initiators for the polymerization by irradiation of organic material which can be polymerized by cations and/or free radicals. The composition composed of the polymerizable material and of the initiator mixture is suitable for the production of protective coatings and can be used as a photographic recording material.

Abstract: An electroconductive polymeric material comprises a dispersion of dicyclopentadienyl iron in a vinyl chloride resin having (--CH.sub.2 --CHCl--) structure in the molecular chain or a vinylidene chloride resin having (--CH.sub.2 --CCl.sub.2 --) structure in the molecular chain irradiated with light having ultraviolet rays. This electroconductive polymeric material can easily be molded because it gels under heating, and can also be formed into a film by dissolving it in an organic solvent and evaporating the solvent after casting or spreading. Doping the electroconductive polymeric material with an anionic dopant after the irradiation provides optical response characteristics with further improved electroconductivity.

Abstract: Titanocenes with, for example, .pi.-cyclopentadienyl ligands in which one or two carbo- or heterocyclic aromatic rings are bonded to the titanium, the aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the metal-carbon bond and being substituted by at least one free or etherified or esterified polyoxaalkylene radical, are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated substrates.

Abstract: When irradiated, a mixture of (a) a non-volatile substance containing at least one olefinic double bond and (b) a dibenzalacetone palladium complex deposits zero-valent palladium. Electrically non-conductive carrier materials which have been coated with a layer of said mixture can, after irradiation, be metallized by metal deposition without current, with electrically conductive coatings or patterns being obtained.

Abstract: A polymerizable composition comprises a polymeric precursor selected from the group consisting of (1) at least one ethylenically-unsaturated monomer, optionally in combination with an epoxy monomer or polyurethane precursors, or (2) at least one epoxy monomer, or (3) polyurethane precursors, and a curing agent comprising an organometallic salt and an onium salt.

Abstract: Titanocenes with, for example, .pi.-cyclopentadienyl ligands in which one or two carbo- or heterocyclic aromatic rings are bonded to the titanium, the aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the matal-carbon bond and being substituted by at least one free or etherified or esterified polyoxaalkylene radical, are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated substrates.

Abstract: Titanocenes with silylated .pi.-cyclopentadienyl ligands in which one or two carbo- or heterocyclic aromatic rings are bonded to the titanium, the aromatic rings being substituted by fluorine, --CF.sub.3, --C.sub.2 F.sub.5, --CF.sub.2 CL or --CF.sub.2 CH.sub.3 in at least one of the two ortho-positions relative to the metal-carbon bonds, are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated substrates. They are distinguished by a high sensitivity, stability to air and the action of heat, and a high activity in the region of UV light to visible light. They are furthermore readily soluble in the photopolymerizable compositions.

Abstract: The invention relates to mixtures containing:(a) cationically polymerizable compound and(b) a compound of the formula I[R.sup.1 (FE.sup.II R.sup.2).sub.a ].sub.q.sup..sym.an an X.sup..crclbar.(I)in which a is 1 or 2, n is 1 or 2, R.sup.1 is a substituted or unsubstituted .pi.-arene, R.sup.2 is a substituted or unsubstituted .pi.-arene or cyclopentadienyl anion or indenyl anion, q is an integer from 1 to 3 and X is FSO.sub.3.sup.- or a q-valent anion of an organic sulfonic acid or of a carobxylic acid; R.sup.1 can also be a polymeric, aromatic ligand. The invention also relates to the novel compounds of the formula I. The curable mixtures can be processed in particular for the production of coatings having a good resistance to heat.

Abstract: A radiation-curable composition useful in forming an abrasion-resistant antistatic layer is comprised of a salt, such as an alkali metal fluoroborate, dissolved in a mixture of (1) a poly(alkylene glycol)diacrylate and (2) an acrylic monomer containing at least three acrylic ester groups. The composition can be coated in the form of a thin layer and cured by suitable means, such as an electron beam accelerator or a source of ultraviolet radiation, to form an antistatic layer of particular utility as a component of a photographic material.

Abstract: A composition including a cationic transition metal coordination complex and a borate anion, wherein said composition is capable of absorbing actinic radiation and producing free radicals which can initiate free radical addition polymerization of a free radical addition polymerizable or crosslinkable monomer is disclosed. The compositions are particularly useful as visible light photoinitiators.

Abstract: A polymerizable composition comprises a polymeric precursor selected from the group consisting of (1) at least one ethylenically-unsaturated monomer, (2) at least one epoxy monomer, and (3) polyurethane precursors, and a curing agent comprising an organometallic compound and an onium salt.

Abstract: Titanocenes containing .pi.-cyclopentadienyl ligands, in which one or two carbocyclic or heterocyclic aromatic rings are attached to the metal atom, said aromatic rings being substituted by fluorine in at least one of the two ortho-positions relative to the metal-carbon bonds, are suitable photoinitiators for the photopolymerization of ethylenically unsaturated substrates. They are distinguished by high sensitivity, stability to air and heat, and are very effective in the range from UV light to visible light.

Abstract: Coatings of polyisocyanates, which contain a latent catalyst of the formula I[(R.sup.1) Fe.sup.II (R.sup.2)].sub.a.sup.+ [X].sup.a- Iin which a is 1, 2 or 3, R.sup.1 is an uncharged carbocyclic or heterocyclic, unsubstituted or substituted aromatic ring, R.sup.2 is an unsubstituted or substituted cyclopentadienyl or indenyl anion and [X].sup.a- is an anion from the series comprising F.sup.-, Cl.sup.-, Br.sup.-, I.sup.-, CN.sup.-, NCO.sup.-, NCS.sup.-, CH.sub.3 COO.sup.-, CF.sub.3 COO.sup.-, SO.sub.4.sup.2-, PO.sub.4.sup.3-, NO.sub.3.sup.-, ClO.sub.4.sup.-, [(phenyl).sub.4 B].sup.-, C.sub.6 H.sub.5 SO.sub.3.sup.-, CH.sub.3 C.sub.6 H.sub.4 SO.sub.3.sup.-, CF.sub.3 C.sub.6 H.sub.4 SO.sub.3.sup.-, CH.sub.3 SO.sub.3.sup.-, CF.sub.3 SO.sub.3.sup.-, C.sub.4 F.sub.9 SO.sub.3.sup.-, C.sub.6 F.sub.13 SO.sub.3.sup.-, C.sub.8 F.sub.17 SO.sub.3.sup.-, C.sub.6 F.sub.5 SO.sub.3.sup.-, BF.sub.4.sup. -, AlF.sub.4.sup.-, AlCl.sub.4.sup.-, TiF.sub.6.sup.2-, PF.sub.6.sup.-, SbF.sub.6.sup.-, SbCl.sub.6.sup.-, GeF.sub.6.sup.

Abstract: The invention provides a process for the production of an image which comprises(i) applying to a substrate a layer of a liquid composition comprising(A) a cationically polymerizable residue(B) a radiation-activated polymerization initator for (A)(C) a radiation-curable residue that is different from (A) and optionally(D) a radiation activated initiator for the cure of (C),(ii) subjecting the composition to actinic radiation having a wavelength at which initiator (B) is activated but at which the residue (C) and/or initiator (D) is not substantially activated, followed by heating, if necessary, so that (A) is polymerized and the layer of liquid composition is solidified, but remains curable,(iii) subjecting the solidified layer in a predetermined pattern to actinic radiation having a wavelength that is different from that of the radiation used in stage (ii) and at which the radiation-curable residue (C) and/or the initiator (D) is activated, such that in the exposed areas (C) is substantially cured, and(iv) re

Abstract: Substituted dibenzalketones useful as water-soluble photoinitiators have the formula: ##STR1## wherein R.sup.1 and R.sup.2 are 4, alkyl or, taken together, an aliphatic ring, n=0 or an integer and R.sup.3 and R.sup.4 either are both water-solubilizing groups (a) --X(CH.sub.2).sub.m N.sup.+ R.sup.5.sub.3, (b) --X(CH.sub.2).sub.m COO.sup.- M or (c) --X(CH.sub.2).sub.m SO.sup.-.sub.3 M.sub.5 or one is such a group and the other is (d) a group --NR.sup.5.sub.2, X is --CH.sub.2 --, --O-- or --S--, R.sup.5 is an alkyl group, M is H.sup.+ or a metal cation and m=0. Such a photoinitiator compound is associated with a polymerizable compound in an aqueous photopolymerizable composition.

Abstract: A curable thiol-ene formulation comprising(a) a polythiol(b) a 'ene compound having a plurality of groups of the formula: ##STR1## where Q is CH.sub.2, CHCH.sub.3, C(Ch.sub.3).sub.2, O, S, NR.sup.1 or SO.sub.2 R.sup.1 is H or alkyl, and m is 0-10, and(c) an effective amount of a free radical initiator.

Abstract: A catalytic amount of a finely divided copper salt catalyst is added to a monomer having at least one cyclobutarene group to lower the peak temperature of the polymerization oxotherm.

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: A method of forming preceramic polymers by mixing (A) an organic polysilane, preferably either a methylpolysilane of the formula [(RSiH).sub.x (RSi).sub.y ].sub.n, (where R is a lower alkyl group having from 1 to about 6 carbon atoms, a cycloalkyl group having from 3 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl- or di(lower)alkylsilyl group x+y=1, (x and y are each >0 and also x=1, y=0), and n is an integer greater than 1) or a polycarbosilane having repeat units of the formula [R.sup.a Si(H)--(CH.sub.2).sub.q ], [R.sup.a Si(H)--CH.dbd.CH], and [R.sup.a Si(H)--C.tbd.C] (where R.sup.

Abstract: Titanocenes with .pi.-cyclopentadienyl ligands, in which one or two carbocyclic or heterocyclic aromatic rings are bonded to the metal, the aromatic rings being substituted in at least one of the two ortho-positions relative to the metal-carbon bonds by CF.sub.2 Z (Z=F or substituted or unsubstituted alkyl), are suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds. They are distinguished by a high radiation sensitivity, stability to air and thermal effects, and high effectiveness in the range from UV light to visible light.

Abstract: A free radical polymerizable composition comprising a free radical polymerizable material and a photoinitiator system therefor comprising appropriate amounts of an alpha-cleavage or homolytic bond cleavage, photoinitiator and a ferrocenium salt, said composition being suitable for use in the preparation of protective layers and photographic images.