Abstract: The invention provides a method of forming a cured coating film which comprises exposing a coating composition consisting of, or containing as a main component, a resin containing polymerizable unsaturated group and aprotic onium-containing group of the formula ##STR1## wherein R.sub.1 means a hydrogen atom or a hydrocarbon group of 1 to 8 carbon atoms which may optionally be substituted by a hydroxyl, alkoxy or ester group or a halogen atom; ##STR2## where Z means a nitrogen atom or phosphorus atom and Y means a sulfur atom; R.sub.2, R.sub.3 and R.sub.4 are the same or different and respectively mean an organic group of 1 to 14 carbon atoms, provided that R.sub.2 and R.sub.3, or R.sub.2, R.sub.3 and R.sub.4 may jointly form a heterocyclic group taken together with the adjacent nitrogen, phosphorus or sulfur atom, to actinic radiation or electron beams to thereby induce a crosslinking reaction and, then, subjecting the composition to heat treatment at a temperature not less than 80.degree. C.

Abstract: The invention relates to a pressure-sensitive thermosetting adhesive comprising from about 30% to about 80% by weight of a photopolymerizable prepolymeric or monomeric syrup containing an acrylic ester and a polar copolymerizable monomer, from about 20% to about 60% by weight of an epoxy resin or a mixture of epoxy resins containing no photopolymerizable groups, from about 0.5% to about 10% by weight of a heat-activatable hardener for the epoxy resin, from about 0.01% to about 5% of a photoinitiator, and from 0% to about 5% of a photocrosslinking agent. In a preferred embodiment, imidazoles and thermally expandable thermoplastic microspheres are utilized in the inventive adhesive formulation.

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: A solder resist composition contains a specified partially acrylated and/or methacrylated bisphenol A novolak epoxy resin component, and a specified partially acrylated and/or methacrylated cresol novolak and/or phenol novolak epoxy resin component. The composition further contain a photopolymerization initiator, a thermosetting agent, an inorganic filler, and an organic solvent. The composition may further include a silane or titanate coupling agent.

Abstract: This invention realtes to a radiation curable cross linkable composition containing (a) from about 0.1 to about 5 wt. % of an initiator containing at least 25% cationic initiator, (b) from about 0 to about 60 wt. % of a polymerizable vinyl ether, expoxide, vinyloxy alkyl urethane or acrylate and (c) from about 35 to about 99.9 wt. % of a polyfunctional alkenyl ether having the formulaA[(CH.sub.2 O).sub.m (Z).sub.r CH.dbd.CHR].sub.nwherein A is a carbon atom, --OCH.dbd.CHR or [C.sub.1 to C.sub.10 alkyl].sub.4-n ; R is C.sub.1 to C.sub.6 alkyl; Z is C.sub.2 to C.sub.8 alkyleneoxy; r has a value of from 0 to 6; m has a value of from 0 to 1 and at least one of r and m has a positive value; n has a value of from 1 to 4, with the proviso that m is 0 and n is one when A is --OCH.dbd.CHR, n has a value of 2 or 3 when A is [C.sub.1 to C.sub.10 alkyl].sub.4-n and n has a value of 4 when A is carbon.

Abstract: A photopolymerizable composition comprising a vinylic compound, a sulfur-containing compound and an .alpha.-diketone is disclosed. The sulfur-containing compound may be a mercaptobenzoic acid or a polysulfide.

Abstract: A curable composition, the cure of which can be monitored optically, comprises at least one of a hydride curable silicone, an ethylenically unsaturated compound, and a cationically polymerizable monomer, and as cure monitor dibenzofulvene or derivatives thereof. The cure monitor is a latent fluorophore which reacts under the cure conditions to form a UV-detectable fluorophore.The invention also provides a method for measuring degree of cure of a polymeric material which can be a coating or an article.

Abstract: The invention relates to a process for the manufacture of coatings by radiocrosslinking. A radio-crosslinkable composition (C) is produced first of all by mixing at least one (meth)acrylic compound (A) with a reactive diluent system comprising at least one mono(meth)acrylic carbonate (B) corresponding to the general formula (I): ##STR1## in which: R.sub.1 denotes H or CH.sub.3R.sub.2 denotes an alkylene ether or alkylene chain which has a total number of carbon atoms of between 2 and 6,n denotes an integer between 1 and 6.The composition (C) is next applied onto a substrate and is then radiocrosslinked, preferably using UV radiation.Another subject of the invention is the crosslinkable compositions (C) in which the compound (A) and the carbonate (B) are not simultaneously 2,3-carbonyldioxypropyl 2-methacryloyloxyethyl carbonate, and carbonates of general formula (I) in which R.sub.2 denotes (CH.sub.2).sub.m and in which m and n are integers such that 2.ltoreq.m.ltoreq.6, 1.ltoreq.n.ltoreq.6 and n.noteq.

Abstract: This invention relates to a radiation curable crosslinkable composition containing (a) from about 0.1 to about 5 wt. % of an initiator containing at least 25% cationic initiator, (b) from about 0 to about 60 wt. % of a polymerizable vinyl ether, epoxide, vinyloxy alkyl urethane or acrylate and (c) from about 35 to about 99.9% wt. % of a polyfunctional alkenyl ether having the formulaA[(CH.sub.2 O).sub.m (Z).sub.r CH.dbd.CHR].sub.nwherein A is a carbon atom, --OCH.dbd.CHR or [C.sub.1 to C.sub.10 alkyl].sub.4-n ; R is C.sub.1 to C.sub.6 alkyl; Z is C.sub.2 to C.sub.8 alkyleneoxy; r has a value of from 0 to 6; m has a value of from 0 to 1 and at least one of r and m has a positive value; n has a value of from 1 to 4, with the proviso that m is 0 and n is one when A is --OCH.dbd.CHR, n has a value of 2 or 3 when A is [C.sub.1 to C.sub.10 alkyl].sub.4-n and n has a value of 4 when A is carbon.

Abstract: Compounds of the general formula I ##STR1## wherein Z is CR.sup.1 R.sup.2 (OR.sup.3) or phenyl,R.sup.1 being H, C.sub.1-6 -alkyl or phenyl,R.sup.2 being H, C.sub.1-6 -alkyl or C.sub.1-6 -alkoxy andR.sup.3 being H, C.sub.1-6 -alkyl or C.sub.1-6 -alkanoyl andZ' is Y-[(CH.sub.2).sub.m -X].sub.n -,X being CH.sub.2 or 0,Y being OH; COOH or SO.sub.3 H including the alkali metal, alkaline earth metal or ammonium salts thereof and also the salts thereof with organic nitrogen bases; or NRR' in which R and R' are in each case H, C.sub.1-20 -alkyl or C.sub.1-4 -hydroxyalkyl, if appropriate quaternized or in the form of the acid addition salts, andn and m each being the numbers 1-4, are excellently suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds, in particular in aqueous systems.

Abstract: A photocurable adhesive composition comprising a phenoxy resin; a reaction product of an unsaturated carboxylic acid and epoxidized non-linear novolak; reaction product of an unsaturated carboxylic acid and a tetrabrominated diglycidyl ether of a phenol; monohydroxy dipentaerythritol acrylate and/or pentaerythritol tetraacrylate; polyethylenically unsaturated compound; and photoinitiator, and optionally, hexamethylol melamine-formaldehyde; and/or a thixotropic agent; and use thereof.

Abstract: The invention relates to the use of a new class of sulphurated derivatives of aromatic-aliphatic or aliphatic ketones as a) polymerization or crosslinking photoinitiators for transparent or pigmented mixtures containing ethylenically unsaturated photopolymerizable compounds, in particular for obtaining polyacrylates, b) photochemically releasable latent acid catalysts, useful for crosslinking systems polycondensable by acid catalysis, of the type comprising etherified aminoplasts together with compounds containing hydroxyl, carboxyl, amido, amino and other functionalities.Said sulphurated derivatives enable manufactured articles to be obtained with exceptionally clear color while maintaining photochemical reactivity at high levels.

Abstract: A method of adhesion which comprises applying a two-step reactive type tacky adhesive agent comprising (1) a non-photopolymerizable epoxy resin or isocyanate compound, (2) a curing agent therefor and (3) a compound having at least one photopolymerizable vinyl group in one molecule onto a substrate, irradiating the whole applied surface with light to develop the tackiness, and sticking the substrate together to a material to be bonded, while the tackiness is retained, followed by curing.The method provides excellent green bonding strength and can permit the satisfactory adhesion without clamping, and can be particularly suitably utilized in the adhesion of materials to be bonded which have a curved surface difficult to be clumped.

Abstract: A photosetting liquid ink composition developable with a dilute alkaline aqueous solution and comprising (A) a resin curable with an activated energy ray, obtained by the reaction of a saturated or unsaturated polybasic acid anhydride with a product of the reaction of a novolak type epoxy compound and an unsaturated monocarboxylic acid, (B) a photopolymerization initiator, and (C) a diluent can be used for the production of an etching resist or a solder resist in the manufacture of a printed circuit. This composition, when combined with a thermosetting component, produces a photosetting and thermosetting liquid ink composition.

Abstract: The photosensitive resin composition comprises (a) a ternary copolymer of an ethylenically unsaturated amide, carboxyl-containing monomer and third monomer, (b) an esterified resin by the reaction of an unsaturated carboxylic acid and a novolactype epoxy resin, (c) a photopolymerizable monomer, (d) a photopolymerization initiator and (e) a powder such as a finely divided silica filler. The resist layer formed from the composition is capable of being developed with an alkaline aqueous solution and has excellent heat resistance in addition to other desirable properties when the patterned resist layer by the pattern-wise exposure to ultraviolet light and development is subjected to a heat treatment to effect thermal curing.

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 dental adhesive composition containing as major components:(a) at least one isocyanate-group-containing urethane prepolymer,(b) at least one isocyanate-group-containing silane compound,(c) at least one radical-polymerizable unsaturated monomer, and(d) at least one initiator selected from the group consisting of redox polymerization initiators and photopolymerization initiatorsis disclosed.This composition is excellent in bonding properties when it is used to bond a living dental tissue with a restoring material such as a metal, organic polymer, and ceramic. Also, this adhesive composition does not require a troublesome pretreatment of the restoring material with an etching agent such as phosphoric acid when the restorating material is required to bond to the living tissue.

Abstract: Disclosed is a flame-retardant liquid photosensitive resin composition consisting essentially of(a) a (meth)acrylate obtained by the reaction of a compound having two or more epoxy groups in the molecule with (meth)acryalic acid and a dibasic acid or its anhydride, the (meth)acrylate having an average acid value of 4 to 150 and a number average molecular weight of 300 to 5,000;(b) a monomer having at least one (meth)acryloxyloxy group and containing not less than 20% by weight of bromine;(c) a monomer having two or more (meth)acryloxyloxy groups in the molecule;(d) a monomer having one (meth)acryloyloxy group in the molecule;(e) at least one inorganic filler; and(f) at least one photopolymerization catalyst selected from the group consisting of photo-initiators and photosensitizers,wherein the content of bromine in the total composition is in the range of 0.5 to 28% by weight.

Abstract: A photosensitive thermosetting resin composition, comprising (A) a photosensitive prepolymer containing at least two ethylenically unsaturated bonds in the molecular unit thereof, (B) a photoinitiator, (C) a photopolymerizable vinyl monomer and/or an organic solvent as a diluent, (D) a finely powdered epoxy compound containing at least two epoxy groups in the molecular unit thereof and exhibiting sparing solubility in the diluent to be used, and optionally (E) a curing agent for epoxy resin, excels in developing property and sensitivity and enjoys a long shelf life.By subjecting this photosensitive thermosetting resin composition to coating, exposure, development, and postcuring, there can be formed a solder resist pattern which excels in adhesion, insulation resistance, resistance to electrolytic corrosion, resistance to soldering temperature, resistance to chemicals, and resistance to plating.

Abstract: A dielectric composition capable of being polymerized for use in sealing electrical and electro-optical connectors and devices is disclosed. Said composition is comprised of a major proportion of vinyl ester resins, a minor proportion of polymerizable acrylic diluent monomers, and a polymerization activation system comprised of from about 0.25 percent to about 17 percent by weight of the resin. A process of the present invention includes applying a layer of said composition to desired areas or to desired locations such as apertures surrounding electrical terminals extending from a connector housing, and exposing said composition to actinic radiation which activates the polymerization activation system which causes the composition to polymerize to form a sealant material that exclused solder and solvents from the connector and its apertures.

Abstract: A composition useful as an alkaline developable liquid photoimageable solder resist ink comprising a photocurable resin, a photopolymerization initiator, a reactive diluent, a solvent and optionally, a thermosetting material as main components wherein the photocurable resin comprises a reaction product of: (A) an epoxy vinyl ester resin obtained by reacting a cresol novolak epoxy resin and an unsaturated monobasic acid, (B) a polybasic acid anhydride and (C) an alkyl ketene dimer, wherein the hydroxyl value of the photocurable resin is not more than 10 carbons. Coating films formed from the subject composition have excellent adhesion, heat resistance, moisture insulation resistance and alkaline developable properties.

Abstract: A solder resist ink composition is disclosed which contains a photo-curable resin obtained by causing an unsaturated monocarboxylic acid to react with a cresolnovolak- or phenolnovolak-type epoxy resin, and causing a polybasic carboxylic anhydride to react with the resultant reaction product, a photo-curable resin obtained by causing an unsaturated monocarboxylic acid to react with a bisphenol A novolak- or cycloaliphatic oxirane novolak-type opoxy resin, and causing a polybasic carboxylic anhydride to react with the resultant reaction product, at least one photo-polymerizable compound selected from photo-polymerizable monomers, a photo-polymerization initiator, an organic solvent, and an inorganic filler. Also disclosed are two other solder resist ink compositions each having a different photo-curable component.

Abstract: In an optical recording disk wherein a resin layer cured with ultraviolet radiation is provided on a surface of a transparent substrate, the present invention consists in that a material having a heat distortion temperature of at least 65.degree. C. is employed for the ultraviolet-cured resin layer. The appearance of wrinkles on a UV-cured resin surface is suppressed, whereby an optical recording disk of high carrier-to-noise ratio and long lifetime can be provided.

Abstract: A resin composition for use in a solder resist ink, said composition comprising as essential ingredients(A) an epoxy vinyl ester resin solution obtained by dissolving (A-a) an epoxy vinyl ester resin obtained by reacting a phenol novolak-type epoxy resin and/or a cresol novolak-type epoxy resin with 0.40 to 0.85 mol, per epoxy group of the epoxy resin, of an unsaturated monobasic acid in (A-b) an organic and/or (A-c) at least one photopolymerizable polyfunctional vinyl monomer selected from the group consisting trifunctional or higher polyoxyalkylene glycol poly(meth)acrylates, poly(meth)acrylates of polyoxyalkyl isocyanurates and poly(meth)acrylates of acetal compounds,(B) a photopolymerization initiator, and(C) a curing agent of an amino group and/or imino group-containing epoxy resin.

Abstract: Acryloylmorpholine and/or methacryloylmorpholine useful as a reactive diluent for UV and EB curable resin compositions, which has low skin irritation, a little odor, low volatility, low weight loss and high workability and which provides, without imparing work environment, UV and EB curable compositions having a high curing rate and capable of forming films of high hardness with small deformation.

Abstract: The present invention comprises a radiation immobilizable epoxy formulation which displays improved initial and thermal cycle strengths when bonding different materials such as terephthalate polyesters and aluminum.The composition comprises:(1) a compound or mixture of compounds having a plurality of epoxy groups per molecule;(2) a polyoxyalkylene amine curative for the epoxy;(3) an imide compound selected from those having the formulas; and ##STR1## (4) a photocurable ethylenically unsaturated compound and photoinitiator, said ethylenically unsaturated compound and photoinitiator present in amounts which together are effective to cause the composition to become immobilized when irradiated with actinic radiation.

Abstract: A high density dimensionally stable encapsulated wire circuit board and a method of making such a board is described. A photo-curable adhesive having a unique combination of rheological properties is utilized to bond insulated wires to a substrate. The unique combination of rheological properties of the adhesive used in the encapsulated wire circuit boards of this invention include a specified range of values for the Storage Shear Modulus and specified range of values for the Loss Angle ratio.A new photo-curable adhesive having these properties and a method of obtaining such an adhesive are also described.

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: A light curing composition for dental restoration comprises (a) a polymerizable compound containing at least one ethylenically unsaturated double-bond, (b) at least one photo-polymerization initiator selected from ketal base compounds defined hereinafter, (c) at least one photopolymerization initiator selected from thioxanthone base compounds defined hereinafter, (d) a reducing agent and (e) a filler.

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: A light curable pit and fissure sealant composition comprises 2,2-propane-bis [3-(4-phenoxy)-1,2-dihydroxy-propane-1- methacrylate] and triethylene glycol dimethacrylate in a 55:45 weight ratio, a polymerization initiator, titanium dioxide as an opaquing agent, and DEA-EMA of at least 95 percent purity as the polymerization accelerator. Optionally, up to 50% filler can be used.

Abstract: A photocurable composition comprising (1) an epoxy compound having at least one epoxy group and at least one unsaturated double bond in the same molecule; (2) a metal compound present in an amount ranging from 0.001 to 10 wt. %, based on the epoxy compound; and (3) a silicon compound which is capable of forming a silanol group when irradiated with light and which is present in an amount ranging from 0.1 to 20 wt. %, based on the epoxy compound, is characterized by a particularly rapid curing rate.

Abstract: A composition and method for providing temporary masking of electrical and electronic components compatible with a high speed production operation. The composition is a radiation curable viscous liquid composition which provides minimal adhesion properties and substantial cohesive properties so that when cured, it can be readily removed in the manner of an adhesive tape. In particular, the radiation curable composition is characterized by cured properties a) of positive adhesion to the substrate to which the composition is applied, but insufficient adhesion to resist peeling forces applied by hand; and b) of sufficient cohesive strength to allow substantially all of the cured composition to be stripped mechanically or by hand in a single piece. Suitably the adhesion of the cured composition (22) to the substrate (16) as measured in the tensile shear mode, is between about 5 and 55 psi.

Abstract: A photopolymerizable composition comprising a vinyl monomer, a mercaptocarboxylic acid/.alpha.-diketone photopolymerization initiator and a storage stabilizer. The composition may admit of a filler, and exhibits excellent mechanical strength, storage stability, color and resistance to coloring, and availability.

Abstract: Disclosed are photocurable compositions which comprise(A) a compound having at least one epoxy group and at least one photocurable unsaturated ethylenic double bond within the same molecule;(B) an organometallic compound and(C) a silicon compound capable of generating silanol group by irradiation of light, or comprise(A) a compound having at least one epoxy group and at least one photocurable unsaturated ethylenic double bond within the same molecule;(E) an epoxy compound;(F) an organic phosphorus compound; and(G) a photosensitizer.The compositions of the present invention have excellent film characteristics such as good adhesion property, light resistance, heat resistance and weathering resistance.

Abstract: A light curing composition for dental restoration comprises (a) a polymerizable compound containing at least one ethylenically unsaturated double-bond, (b) at least one photo-polymerization initiator selected from ketal base compound as defined herein, (c) at least one photo-polymerization initiator selected from anthraquinone base compounds as defined herein, (d) a reducing agent and (e) a filler.

Abstract: Disclosed is a liquid photosensitive resin composition comprising(a) an at least partially carboxyl-modified multifunctional epoxy acrylate and/or multifunctional epoxy methacrylate having an average acid value of 4 to 150 and a number average molecular weight of not greater than 5,000,(b) an acrylic and/or methacrylic cross-linking monomer and/or oligomer other than the epoxy acrylate and/or epoxy methacrylate,(c) an acrylic and/or methacrylic monoethylenically vinyl monomer,(d) an inorganic filler, and(e) a photo-initiator and/or photosensitizer.This liquid photosensitive resin composition has excellent alkali developability, yields a cured coating film having good adhesion and good electrical insulating properties under high-humidity conditions, and is suitable for use as a solder resist in the fabrication of printed circuit boards.

Abstract: The inventive photosensitive resin composition has excellent heat resistance, adhesiveness to substrate surface and photosensitivity and suitable as a material for solder resist or plating resist on printed circuit boards. The resin composition comprises, in addition to a photopolymerization initiator and curing agent for epoxy resins, a resinous ingredient composed of a diallyl phthalate resin, a first esterified resin as a reaction product of a cresol novolac type epoxy resin and 0.2-0.8 mole per mole of epoxy groups of an ethylenically unsaturated carboxylic acid and a second esterified resin as a reaction product of a phenol and/or cresol novolac type epoxy resins and 0.9-1.1 moles per mole of epoxy resins of an ethylenically unsaturated carboxylic acid in a limited proportion.

Abstract: An actinically curable composition containing (1) an oligomer having a molecular weight within the range of from about 200 to about 3000 and which is end capped with reactive functional groups to provide sites for free radical polymerization by actinic radiation and (2) as a reactive diluent, an N-vinyl-2-oxazolidinone in which the number 4 and 5 carbon atoms each have two constituents which are all independently selected from hydrogen and alkyl radicals having from 1 to 4 carbon atoms.

Abstract: An actinically curable composition containing (1) an oligomer having a molecular weight within the range of from about 200 to about 3000 and which is end capped with reactive functional groups to provide sites for free radical polymerization by actinic radiation and (2) as a reactive diluent, an N-vinyl-2-oxazolidinone in which the number 4 and 5 carbon atoms each have two constituents which are all independently selected from hydrogen and alkyl radicals having from 1 to 4 carbon atoms.

Abstract: A printable dielectric composition comprising finely divided particles of talc and/or mica dispersed in a curable liquid composition containing acrylated rubber modified epoxy resin oligomer, acrylated polydiene oligomer and alkyl acrylate.

Abstract: A novel light curing composition for dental restoration comprises (a) a polymerizable compound containing at least one ethylenically unsaturated double-bond, (b) at least one photo-polymerization initiator selected from ketal base compounds defined hereinafter, (c) at least one photo-polymerization initiator selected from benzoin alkyl ether base compounds defined hereinafter, (d) a reducing agent and (e) a filler.

Abstract: Ultraviolet curable terpolymers of trioxane, from at least 65 weight percent to about 75 weight percent of 1,3-dioxolane and from about 2 weight percent to about 20 weight percent of a monoethylenically unsaturated aliphatic diol formal having at least 4 carbon atoms in its main chain, e.g., 4,7-dehydro- 1,3-dioxepin, which are non-crystalline at room temperature or above are disclosed. These terpolymers, when admixed with a multifunctional crosslinking monomer, e.g., a multifunctional acrylate such as 1,6-hexanediol diacrylate, and a photosensitizer, e.g., a benzoin compound such as benzoin isobutyl ether, can be cured to an insoluble, non-tacky, rubbery state using UV radiation. The thus-cured polymeric materials form useful crosslinked films, and when cryogenically ground to a suitable small particle size can be blended with conventionally prepared crystalline oxymethylene homo-, co- and terpolymers to improve the latters' impact properties.

Abstract: As initiators for the photopolymerisation of ethylenically unsaturated compounds, the use of systems consisting of compounds of benzophenone type of formula I ##STR1## in which R, R' and R.sup.2 are preferably alkyls of 1-4 carbon atoms, R.sup.3 and R.sup.4 are preferably hydrogen and Ar is preferably phenyl, in combination with donors of hydrogen or substances which determine the formation of labile photochemical complexes, such as alcohols, ethers and tertiary amines with hydrogen in the alpha position, and the use for the same purpose of mixtures of 2,4,6-trialkylbenzophenones and benzophenone and particularly of a mixture of 2,4,6-trimethylbenzophenone and benzophenone in a molar ratio of 1.155, which has the advantage of being liquid at temperatures exceeding 10.degree. C. and of possessing photochemical activity superior to that of benzophenone.

Abstract: Buffer-coated and overcoated optical glass fiber is disclosed in which the topcoat has the high strength and high tensile modulus combined with good elongation and solvent resistance associated with extruded jacket coatings, but which is applied by ordinary coating procedures and cured by exposure to ultraviolet radiation. The coating compositions which enable this to be achieved comprise an ultraviolet curable coating composition comprising, based on total reactive components, from about 60% up to about 85% of a diepoxide polyacrylate combined with at least about 15% of an monacrylate-functional monomer having a glass transition temperature below 0.degree. C. to provide desired coating viscosity. The diepoxide is a diglycidyl ether of a bisphenol having a molecular weight in the range of about 560 to about 2000 and contains at least 1.8 oxirane groups per molecule, substantially all of these oxirane groups being consumed in the polyacrylate.

Abstract: A highly adherent photopolymerizable composition comprises a (hydroxy)phosphinylalkyl monomer of the formula ##STR1## wherein R is hydrogen, methyl or ethyl and R' and R" are selected independently from hydrogen and alkyl of 1-10 carbon atoms; at least one copolymerizable ethylenically unsaturated monomer and a photoinitiator.

Abstract: In dry film resists possessing a solid photopolymerizable resist layer, which is applied on a temporary base and can be developed with aqueous, in particular aqueous alkaline, media, and, if required, a cover sheet on the resist layer, the said resist layer is built from a homogeneous mixture of (a) not less than 40% by weight of one or more oligomers which contain free carboxyl groups and more than two acryloyl and/or methacryloyl groups and are soluble or dispersible in aqueous alkaline solutions, (b) from 1 to 35% by weight of one or more film-forming compatible polymers which are soluble in aqueous media, (c) from 1 to 30% by weight of one or more compatible photopolymerizable monomers, (d) from 0.001 to 10% by weight of one or more photoinitiators and (e) from 0 to 30% by weight of further additives and/or assistants. Resist images are produced on a substrate by a process employing photopolymerizable resist layers of the type stated above.

Abstract: Acylphosphine oxide compounds of the general formula ##STR1## where R.sup.1 is alkyl, cyclohexyl, cyclopentyl, aryl which is unsubstituted or substituted by halogen, alkyl or alkoxy, or an S-containing or N-containing five-membered or six-membered heterocyclic radical,R.sup.2 has one of the meanings of R.sup.1 (but R.sup.1 and R.sup.2 may be identical or different) or is alkoxy, aryloxy or aralkoxy, or R.sup.1 and R.sup.2 together form a ring andR.sup.3 is an at least disubstituted phenyl, pyridyl, furyl or thienyl radical which carries, at least at the two carbon atoms adjacent to the linkage point of the carbonyl group, the substituents A and B, which may be identical or different, and each of which is alkyl, alkoxy or alkylthio of 1 to 6 carbon atoms, cycloalkyl of 5 to 7 carbon atoms, phenyl or halogen, or R.sup.3 is .alpha.-naphthyl substituted by A and B at least in the 2- and 8-positions or is .beta.

Abstract: A resin composition is suitable to seal an electronic device, when cured, and comprises:(a) an unsaturated alicyclic epoxy ester compound obtained by reacting an alicyclic epoxy compound having at least two epoxy groups in the molecule with 0.5 to 1.1 equivalent, per equivalent of the epoxy group, of acrylic or methacrylic acid,(b) a polymerizable vinyl monomer, and(c) a photopolymerization initiator.

Abstract: Dental restoration materials with improved properties, particularly X-ray opacity and polishability, are obtained, if they contain fillers and polymerizable compounds consisting in total or in part of one or more compounds of the general formula ##STR1## where R represents H or a methyl group, X is representing a ##STR2## and n means 0 to 3.