Abstract: An ink jet ink includes a colorant and a liquid component containing at least one of an epoxy and a vinyl ether. Water may also be dissolved in the liquid component. Preferably, the vinyl ether is ethylene glycol monovinyl ether. An ink jet recording process includes the steps of ejecting an ink jet ink, such as the inks of the present invention, from an orifice to form an image on a recording medium.

Abstract: Disclosed is a process for preparing a UV-curable coating material comprising the steps of effecting a hydrolysis reaction of (a-1) 40 to 90 parts by weight of colloidal silica, and (a-2) 60 to 10 parts by weight of a hydrolyzate of an alkoxy silane compound containing not less than 50% by weight of a compound of the formula (I) ##STR1## replacing the dispersion medium of the colloidal silica with a nonpolar solvent when the amount of dehydration is in the range of 50 to 90% of theoretical value; and effecting a further condensation reaction while maintaining in the state of 30 to 90% by weight of solid components in the presence of the nonpolar solvent.A coating composition containing the UV-curable coating material can form an anti-abrasion-coating film having excellent abrasion resistance, surface smoothness, thermal resistance, chemical resistance, durability, weather resistance and adhesion to the substrate.

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: Process for continuous preparation of homo- and copolyoxymethylenes with stable end groups in a homogeneous phase, in which in a tubular reactor with static mixing elements cyclic formaldehyde oligomers are polymerized in the presence of protonic acids as initiators in amounts of 0.005 to 500 ppm in a polymerization zone, in which the residence time of the reaction components in this zone is 0.1 to 10 min and in which the initiator is deactivated immediately after polymerization, there being a fluid transition between the polymerization and deactivator zones which is determined solely by the addition of deactivator, and in which, besides deactivation, stabilization of the chain ends is carried out in the presence of residual monomers, with the volatile constituents being removed from the reaction mixture in a subsequent vent unit. Stabilization is carried out in the presence of alkaline substances, either at temperatures of 150.degree. C. to 250.degree. C.

Abstract: Radiation-curable acrylates are prepared by a process in which the hydroxy compound is reacted with acrylic acid or methacrylic acid in a first stage and, in a second stage, the reaction product of the first stage is reacted with an epoxide compound in the presence of, as a catalyst, a quaternary ammonium or phosphonium compound of the general formula ##STR1## where X.sup.- is an opposite ion and R.sup.1 to R.sup.4 independently of one another are each C.sub.1 -C.sub.18 -alkyl which may be substituted by one or two phenyl groups or are each C.sub.6 -C.sub.12 -aryl which may be substituted by one or two C.sub.1 -C.sub.6 -alkyl groups.

Abstract: Ethylenically unsaturated polymerisable compounds can be cured with daylight or with light sources equivalent to daylight by using as hardener a photoinitiator of formula I ##STR1## wherein R.sub.1 is C.sub.1 -C.sub.12 alkyl, cyclopentyl, cyclohexyl, unsubstituted phenyl, naphthyl or biphenyl,R.sub.2 and R.sub.3 are each independently of the other C.sub.1 -C.sub.12 alkyl,R.sub.4 is hydrogen or C.sub.1 -C.sub.12 alkyl, andR.sub.5 is hydrogen or methyl.

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: 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: Compounds of the formula I ##STR1## in which R.sub.1 is C.sub.1 -C.sub.18 alkyl, cyclopentyl or cyclohexyl, and R.sub.2 and R.sub.3, independently of one another, are phenyl which is unsubstituted or monosubstituted to tetrasubstituted by halogen, C.sub.1 -C.sub.4 alkyl and/or C.sub.1 -C.sub.4 alkoxy, with the proviso that R.sub.1 is not decyl if R.sub.2 and R.sub.3 are chlorine-substituted phenyl, are suitable for the photopolymerisation of compounds containing ethylenically unsaturated double bonds.

Abstract: Disclosed is a coating composition comprising(A) 5 to 60 parts by weight, on a solid basis, of colloidal silica,(B) 5 to 70 parts by weight of a hydrolyzate and/or hydrolyzed and partially condensed product of a compound of the general formula ##STR1## (C) 10 to 80 parts by weight of a polyfunctional monomer containing a monomer of the general formula ##STR2## and (D) 0.01 to 5 parts by weight of a photopolymerization initiator containing a compound of the general formula ##STR3## provided that the combined amount of components (A), (B), (C) and (D) is 100 parts by weight.This coating composition can be cured in air by exposure to ultraviolet light, and the resulting cured film is excellent in various properties (such as abrasion resistance) and adhesion to the substrate.

Abstract: Vinyl monomers are polymerized in the presence of bi(phosphine oxides) and bi(phosphine sulfides) which can function as photoinitiators and chain transfer agents in the polymerization of vinyl monomers. The incorporation of such organo-phosphorous compounds into such polymers either as an integral part thereof, or as an admixture, results in improved thermal stability of the polymers.

Abstract: A composition which is cured upon exposure to ultraviolet light in the absence of solvent is disclosed. The liquid composition is prepared by combining a liquid maleate polyester and at least one of a vinyl compound and an allyl functional compound. A photoinitiator is then added to the polymerizable liquid composition. A substrate is impregnated with the polymerizable liquid composition and exposed to actinic energy of a sufficient dosage for a sufficient amount of time to polymerize the composition to a sufficient degree to impart useful properties to the substrate. The composition can be used as a binder for fiberglass insulation, in the manufacture of transparent or semi-transparent paper and to manufacture paper for use in photocopy machines.

Abstract: Arenebisphosphine oxides of the general formula ##STR1## where R.sup.1 to R.sup.4 independently of one another are each hydrogen, C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.6 -alkoxy, C.sub.5 -C.sub.10 -aryl, C.sub.5 -C.sub.12 -aryloxy or C.sub.7-C.sub.14 -arylalkoxy, R.sup.5 and R.sup.6 independently of one another may each be C.sub.1 -C.sub.6 -alkyl, C.sub.5 -C.sub.10 -cycloalkyl or C.sub.5 -C.sub.12 -aryl, each of which may furthermore contain one or two nitrogen or sulfur atoms in the ring system or carry one or two halogen atoms or C.sub.1 -C.sub.6 -alkyl or C.sub.1 -C.sub.6 -alkoxy groups as substituent on the ring system, or C.sub.1 -C.sub.6 -alkoxy, C.sub.3 -C.sub.8 -alkoxyalkoxy, C.sub.5 -C.sub.12 -aryloxy or C.sub.7 -C.sub.14 -arylalkoxy, or R.sup.5 and R.sup.6 together form a bridge of 2 to 10 carbon atoms, in which some of the carbon atoms may furthermore be part of an aromatic ring.

Abstract: The invention relates to acyl-(2'-hydroxydiphenyl-2-yl)-phosphinic acid salts of formula (I) ##STR1## in which each of the radicals R.sup.1, R.sup.2 and R.sup.3 may be included singly or multiply and in which R.sup.1 and R.sup.2 are mutually independently hydrogen, an alkyl or alkoxy radical with 1 to 6 carbon atoms or halogen with an atomic number of 9 to 35; R.sup.3 means the same as R.sup.1 or R.sup.2 ; Ar is an aromatic hydrocarbon radical with 6 to 10 carbon atoms; and Me is a cation of at least one alkaline metal or N(R.sup.4).sub.4 + in which the radicals R.sup.4 are the same or different and stand for an alkyl radical with 1 to 6 carbon atoms. The invention also relates to a process for producing these compounds (I) and their use as photoinitiators in photopolymerisable materials, preferably on an aqueous basis.

Abstract: A photocurable composition comprising the reaction products of hydroxy terminated liquid sulfide or polysulfide oligomers with photocurable ethylenically unsaturated compounds. The products provide improved sealants for air and marine vehicles.

Abstract: Compounds of formula I ##STR1## wherein n is 0 or 1, p is a number from 1 to 8,q is 2 or 3, andR.sub.1 is unsubstituted phenyl or phenyl which is substituted by one to three halogen, C.sub.1 -C.sub.8 alkyl, C.sub.1 -C.sub.8 alkoxy, C.sub.2 -C.sub.8 alkoxyalkyl or/and C.sub.1 -C.sub.4 alkylthio, are suitable for use as initiators for photopolymerising compounds containing ethylenically unsaturated double bonds.

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 radiation curable coating composition comprising acrylate oligomers and monomers, vinyl ether monomers, and a free radical photoinitiator. The vinyl ether monomers replace N-vinyl-pyrrolidone or other undesirable reactive diluents while retaining or modifying the properties of coatings using such diluents.

Abstract: A free-radical radiation curable composition comprising:a) at least one compound containing one to six vinyl ether groups; andb) at least one compound containing a urethane backbone with one to six maleate and/or fumarate end groups,wherein the ratio of vinyl ether groups to maleate and/or fumarate groups is in the range of about 1 to about 1:5.

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: A free-radical radiation curable composition comprising:a) at least one compound containing from one to about six vinyl ether groups; andb) at least one product obtainable by the reaction of a half-ester of maleic and/or fumaric acid with an epoxy functionalized compound,wherein the ratio of vinyl ether groups to maleate and/or fumarate groups is in the range of about 5:1 to about 1:5.

Abstract: A free-radical radiation curable composition comprising:a) at least one compound containing from one to about six vinyl ether groups; andb) at least one compound containing a saturated backbone and at least one maleate or fumarate end group per molecule,wherein the ratio of vinyl ether groups to maleate or fumarate groups in the composition is in the range of about 5:1 to about 1:5.

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: UV curable hardcoat compositions are provided which impart improved abrasion resistance to thermoplastic substrates when applied and cured thereon. Enhancement in abrasion and weathering properties have been achieved by the use of certain UV curable branched or carbocyclic monoacrylates, such as isobornyl acrylate.

Abstract: Compounds of the formula I ##STR1## in which at least one of the radicals R.sub.1, R.sub.2 and R.sub.3 is a substituted alkyl radical or cycloalkyl radical, or R.sub.1 and R.sub.2 together with the phosphorus atom form a monocyclic or tricyclic ring, are effective photoinitiators for the photopolymerization of ethylenically unsaturated compounds.

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: Silylated acylphosphine oxides of formula I ##STR1## in which R.sub.1, R.sub.2 and R.sub.3 are defined in the specification, are highly suitable as photoinitiators for the photopolymerization of compounds which can be polymerized by means of free radicals, namely 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: Organophosphorus compounds capable of being activated with light at from 360 nm to about 410 nm, such as, an acylphosphine oxide, have been found useful as photoinitiators for effecting the cure of various UV curable coating compositions, such as a UV curable organic material in the presence of up to 20% by weight of a UV absorber. UV stabilized thermoplastic composites of films, sheets, or laminates having thickness of up to an inch or more with improved optical clarity also are provided.

Abstract: Disclosed is a curable silicone composition comprising: (A) an organopolysiloxane having a silicon-bonded unsaturated aliphatic radical; (B) an organopolysiloxane having a silicon-bonded mercaptoalkyl radical; and (C) a photoreaction-initiating amount of photoreaction initiator. The photoreaction initiator includes arylcarbonyl phosphine oxide compounds, having a radical selected from the group consisting of substituted and unsubstituted aryl radicals, and another two radicals selected from the group consisting of substituted and unsubstituted monovalent hydrocarbon radicals. The above silicone, composition is efficiently cured by visible light radiation and usable for photo-curable adhesives.

Abstract: Photopolymerizable dental compositions are proposed which are curable with visible light and which apart from usual auxiliary substances and additives contain polymerizable monomers of the group of the poly-thiol compounds and of the group of the poly-ene compounds and a photoinitiator and which, in order to obtain a curing free from any smeary layer, contain at least 10% by weight poly-thiol compound(s), at least 10% by weight poly-ene compound(s) and 0.01 to 5% by weight of at least one acyl phosphine compound as photoinitiator. The compositions can advantageously be used as dental impression compositions.

Abstract: The invention relates 6-acyl-(6H)-dibenz[c,e][1,2]oxaphosphorine-6-oxides of the formula ##STR1## wherein each of R.sup.1, R.sup.2 and R.sup.3 may be present one or more times and R.sup.1, R.sup.2 and R.sup.3 represent halogen having an atomic number of from 9 to 35, alkyl or alkoxy each having from 1 to 6 carbon atoms and wherein Ar represents an aromatic hydrocarbon group having from 6 to 10 carbon atoms.The invention further relates to a process for the preparation of the afore-mentioned compounds and polymerizable compositions containing them as an essential ingredient as a photo-initiator. Finally the invention relates to 6-alkoxy-(6H)-dibenz[c,e][1,2]oxaphosphorin of the formula II ##STR2## wherein each of R.sup.1 and R.sup.2 may be present once or more times and R.sup.1 and R.sup.2 represent halogen having an atomic number of from 9 to 35, alkyl or alkoxy each having from 1 to 6 carbom atoms, at least one R.sup.1 being, however, halogen, and wherein R.sup.

Abstract: Compounds of the formula ##STR1## in which a is 1, 2, or 3, R.sup.1 is an uncharged, carbocyclic or heterocyclic aromatic ring, unsubstituted or substituted, R.sup.2 is an unsubstituted or substituted cyclopentadienyl or indenyl anion, and .vertline.X.vertline..sup.a- is an a-valent anion, are suitable for use as latent curing catalysts for two-component polyurethane coatings which are activated by irradiation with actinic light or by heating.

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: Esters of dihydric alcohols with alkenylphosphonic or alkenylphosphinic acids which are polymerizable by free radicals are described. They are combined with polymer binders, in particular water-soluble polymers, and photoinitiators forming free radicals to give photopolymerizable mixtures which are suitable for the production of photoresists and printing plates. The mixtures display low heat-sensitivity and have long shelf lives.

Abstract: A photopolymerizable coating composition comprising:(A) 100 parts by weight of a vehicle consisting essentially of a urethaneacrylate oligomer;(B) from 0.1 to 5 parts by weight of an acylphosphine oxide compound as a photoinitiator;(C) from 1 to 100 parts by weight of a color pigment; and(D) from 20 to 300 parts by weight of a transparent glass powder having an average particle size of not larger than 100 .mu.m and an index of refraction which does not differ more than 0.3 from the index of refraction of the composition excluding the color pigment.

Abstract: A molding composition for making casting patterns is described containing(a) 10-99.89, preferably 20-90%, by weight of at least one di or polyfunctional acrylic acid and/or methacrylic acid ester which burns without residue,(b) 0.01-5% by weight of an initiator system which can initiate the radical polymerization and(c) 0-80, preferably 10-70%, by weight of organic fillers, pigments and other auxiliary substances burning without residue,the quantity particulars each being related to the total amount of (a)+(b)+(c), characterized in that it further contains(d) 0.1-30, preferably 1-20%, by weight with respect to the component (a) of a chemically inert organic compound burning without residue and having a boiling point and/or sublimation point in the range >150.degree. C.This molding composition is distinguished by not causing any faults in the casting jacket, in particular no crack formation, on burning out of the mold.

Abstract: An actinic ray curable composition for casting polymerization which comprises:(A) 40-90 parts by weight of an urethane poly(meth)acrylate having at least two (meth)acryloyl groups in one molecule,(B) 10-60 parts by weight of a radical polymerizable vinyl monomer having a boiling point of 100.degree. C. or higher, and(C) 0.005-5 parts by weight, per 100 parts by weight of total of the above components (A) and (B), of at least one member selected from methylphenyl glyoxylate, 2-hydroxy-2-methyl-1-phenylpropane-1-one, hydroxycyclohexyl phenyl ketone and a photo-initiator represented by the general formula (I): ##STR1## (wherein R.sub.1 and R.sub.2 which may be identical or different each represents a phenyl group, a methoxy group, an ethoxy group or an isopropyloxy group) and a casting polymerization molded product obtained by radical polymerization of said composition by irradiation with actinic ray.

Abstract: Disclosed are dental adhesive compositions consisting essentially of(a) at least one urethane prepolymer containing one or more isocyanate groups, or a blend of the urethane prepolymer and an inert diluent;(b) at least one radical-polymerizable unsaturated monomer;(c) a photopolymerization initiator;and, if desired,(d) a polymerizable phosphoric ester compound having a specific structure.These dental adhesive compositions can be used to bond a restorative material to dentin without requiring any troublesome pretreatment with an etching agent such as phosphoric acid, and can exhibit bonding power sufficient for practical purposes.

Abstract: A biologically compatible adhesive dental primer that is shelf stable as a single component adhesive and includes a mixture of an adhesive promoting and polymerizable monomer system having a free radical polymerizable monomer or prepolymer having ethylenic unsaturation and a phosphorus containing adhesion promoter which is free from halogen atoms bonded directly to a phosphorus atom, and optionally a free radical polymerization catalyst, and an accelerator for the catalyst.

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: Novel photopolymerizable recording materials, in particular for the production of printing plates and relief plates, can be developed with water or an aqueous alkaline solution and predominantly consist of a photoinitiator-containing mixture of (a) one or more low molecular weight compounds having one or more photopolymerizable olefinically unsaturated double bonds and (b) one or more organic polymeric binders and contain a bisacylphosphine oxide as the photoinitiator.These recording materials are useful for the production of printing plates and relief plates.

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: The invention relates to a sealing compound which contains unsaturated polyester resins, crosslinking agents, light initiators, and elasticity-modifying agents as well as, optionally, adjuvants, pigments, and/or dyes. The invention also relates to a method for the production of the sealing compound and to its use on or in building structures.

Abstract: Homogeneous hydrogels comprise a water-soluble sugar, derivative or mixture thereof, radiation cross-linked with at least one ethylenically unsaturated compound. A preferred combination is sucrose or glucose cross-linked with acrylic acid. The hydrogels may contain additives e.g. plasticizers such as glycerol. The hydrogels are strong and expand to a large extent e.g. 30.times. on water absorption. They are particularly suitable for use in medical dressings, preferably bonded to a supporting film which may be a semi-permeable membrane allowing control of water loss. A method for preparing such a hydrogel and dressing is also described.

Abstract: Supported initiators for the radiation-activated polymerization of cationically-polymerizable compounds, particularly epoxide group-containing compounds, are described. The supported initiators comprise a particulate carrier and a photocatalytic ionic salt. The supported initiators are especially useful for the polymerization of cationically-polymerizable compounds in which the ionic salt alone is not soluble.

Abstract: A polymer having allyl groups each attached to a silicon atom serves as a resist material which is highly resistive to dry etching such as reactive sputter etching with oxygen and sensitive to electron beams, X-rays and deep UV rays. By the addition of a bis-azide compound known as a photosensitive cross-linking agent the resist material becomes sensitive also to UV and near UV rays. A very suitable polymer is obtained by polymerizing either a triallylsilane or an allylsilylstyrene or by copolymerizing an allylsilylstyrene with another ethylenic compound copolymerizable with styrene. This resist material is used in a pattern forming method of the two-layer type, in which a fine pattern is generated in a thin film of the resist material by lithography and then transferred into an underlying thick organic layer by dry etching of the thick organic layer with the resist pattern as a mask.