Tri-functional reactive diluent for curable compositions

Abstract

The present invention relates to a reactive diluent of formula (1) R1 wherein R1 is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, C6-14-aryl, C3-12-heteroaryl, C5-12-cycloalkyl, C5-12- cycloalkenyl or C4-12-heterocycloalkyl, wherein C4-9-alkyl can be substituted with phenyl, C3-8-heteroaryl, C5-8-cycloalkyl, C4-8-cycloalkenyl or C4-8-heterocycloalkyl, and C6-14-aryl, C3-12-heteroaryl, C3-12-cycloalkyl, C5-12-cycloalkenyl and C4-12-heterocycloalkyl can be substituted with C1-10-alkyl, phenyl, C3-8-heteroaryl, C5-8-cycloalkyl or C4-8-heterocycloalkyl, R2 is H or methyl. and n is 1.0 to 6.0, and to compositions comprising the reactive diluent and at least one oligomer or polymer curable by radical polymerization, to cured layers formed from the composition, the substrates coated with the cured layer, to a process for the preparation of the reactive diluent, to a process for the preparation of a precursor of the reactive diluent and to the use of the compositions as paint or varnish composition. n is 1.0 to 6.0, and to compositions comprising the reactive diluent and at least one oligomer or polymer curable by radical polymerization, to cured layers formed from the composition, the substrates coated with the cured layer, to a process for the preparation of the reactive diluent, to a process for the preparation of a precursor of the reactive diluent and to the use of the compositions as paint or varnish composition.

Description

[0001] Tri-functional reactive diluent for curable compositions

[0002] Description

[0003] The present invention relates to a reactive diluent, to compositions comprising the reactive diluent and at least one oligomer or polymer curable by radical polymerization, to cured layers formed from the compositions to substrates coated with the cured layers, to a process for the preparation of the reactive diluent, to a process for the preparation of a precursor of the reactive diluent, and to the use of the compositions as paint or varnish compositions.

[0004] Curable compositions have many applications, for example as coating compositions such as paint or varnish compositions, as ink compositions, as resist compositions used in photolithographic processes, and as reactive compositions used in 3D-priniting processes.

[0005] 100% curable compositions refer to compositions substantially not comprising any water or organic solvent. 100% curable compositions usually comprise an oligomer or polymer curable by radical polymerization and a radical initiator.

[0006] As compositions comprising an oligomer or polymer curable by radical polymerization and a radical initiator, are usually too viscous for most applications, 100% curable compositions usually also contain a reactive diluent to decrease the viscosity, which, upon light or heat treatment copolymerize with the oligomer or polymer.

[0007] 100% UV-curable coating compositions comprising an acrylated or methacrylated oligomer or polymer curable by radical polymerization, an acrylated or methacrylated reactive diluent and a photoinitiator are known in the art.

[0008] R. Schwalm, L. Haussling, W. Reich, E. Beck, P. Enenkel, K. Menzel Progress in Organic Coatings 32, 1997, 191 to 196 describes UV-curable coating compositions comprising epoxy acrylate, polyester acrylate, polyether acrylate and urethane acrylate, respectively, a reactive diluent selected from the group consisting of hexanediole diacrylate, olifoether acrylate, di(propyleneglycol) diacrylate and tri (propyleneglycol) diacrylate, and a photoinitiator.

[0009] D.K. Chattopadhyay, Siva Sankar Panda, K.V.S.V. Raju Progress in Organic Coatings 54, 2005, 10 to 19 describes UV-curable coating compositions comprising acrylated or methacrylated epoxy resin, 5, 7.5 and 10% (weight / weight), respectively, 1 ,1 ,1- trimethylolpropane triacrylate (TMPTA) and photoinitiator. The epoxy resins used are epoxy novolac resin and bisphenol A diglycidyl ether epoxy resin.

[0010] Usually, the oligomer or polymer curable by radical polymerization present in a composition is chosen to obtain a composition that forms cured layers of properties desired in the respective application. For example, the oligomer or polymer curable by radical polymerization present in a coating composition is chosen to obtain a coating composition that forms cured layers of good adhesion to the substrate, high hardness and / or good chemical resistance.

[0011] However, the reactive diluent that is added to the composition to decrease the viscosity of the composition has usually also an impact on the properties of the cured layer. This is a disadvantage as a variation in the ratio of oligomer or polymer curable by radical polymerization to reactive diluent leads to compositions that form cured layers of different properties. Thus, for example, a paint or varnish manufacturer is less flexible to adapt the viscosity of the paint or varnish composition by addition of further reactive diluent without altering the final properties of the paint or varnish.

[0012] It was the object of the present invention to provide a reactive diluent that can be used in curable compositions comprising the at least one oligomer or polymer curable by radical polymerization to decrease the viscosity of the composition to an acceptable vicosity and at the same time the compositions comprising the reactive diluent and the oligomer or polymer curable by radical polymerization form cured layers with no or or only not-significant variations of the hardness of the cured layer over a wide range of ratios of oligomer or polymer curable by radical polymerization to reactive diluent.

[0013] This object is solved by the reactive diluent of claim 1 , the composition of claim 6, the layers of claim 13, the substrate of claim 14, the processes of claims 15 and 16 and the use of claim 17.

[0014] The reactive diluent of the present invention is a compound of formula wherein

[0015] R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein

[0016] C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-8-cycloalkenyl or C4-8-heterocycloalkyl, and

[0017] Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl,

[0018] R2is H or methyl and n is 1.0 to 6.0.

[0019] Ci- -alkyl, C4-9-alkyl, Cs-s-alkyl and Cs-6-alkyl can be branced or unbranched. Examples of C1-10- alkyl are methyl, ethyl, butyl, iso-butyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, 2-ethylhexyl, 1 ,1-dimethyl-3,3-dimethylbutyl, nonyl and decyl. Examples of C4-9-alkyl are butyl, iso-butyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, 2-ethylhexyl, heptyl, octyl, 1 , 1 -dimethyl- 3,3-dimethylbutyl and nonyl. Examples of Cs-s-alkyl are pentyl, isopentyl, hexyl, heptyl, octyl, 2- ethylhexyl and 1 ,1-dimethyl-3,3-dimethylbutyl. Examples of Cs-6-alkyl are pentyl, isopentyl and hexyl.

[0020] Cs-s-alkenyl and C4-9-alkenyl can be branched or unbranched. Examples of Cs-s-alkenyl are pent-4-en-1-yl, pent-3-en-1-yl, hex-5-en-1-yl, hex-3-en-1-yl, hept-6-en-1-yl and oct-7-en-1-yl. Examples of C4-9-alkenyl are but-3-en-1-yl, pent-4-en-1-yl, pent-3-en-1-yl, hex-5-en-1-yl, hex-3- en-1-yl, hept-6-en-1-yl, oct-7-en-1-yl and non-8-en-1-yl.

[0021] Cs-s-alkinyl and C4-9-alkinyl can be branched or unbranched. Examples of Cs-s-alkinyl are pent-4- in-1-yl, pent-3-in-1-yl, hex-5-in-1-yl, hex-3-in-1-yl, hept-6-in-1-yl and oct-7-in-1-yl. Examples of C4-9-alkinyl are but-3-in-1-yl, pent-4-in-1-yl, pent-3-in-1-yl, hex-5-in-1-yl, hex-3-in-1-yl, hept-6-in- 1-yl, oct-7-in-1-yl and non-8-in-1-yl.

[0022] Examples of Ce-14-aryl are phenyl, 1 -naphthyl and 2-naphthyl.

[0023] Examples of Cs-s-heteroaryl and of C3-i2-heteroaryl are

[0024] Examples of Cs-s-cycloalkyl are cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. Examples of C3-i2-cycloalkyl are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl. Examples of Cs-8-cycloalkenyl are cyclopent-3-en-1-yl, cyclohex-2-en-1-yl, cyclohex-3-en-1-yl, cyclohept-3-en-1-yl and cyclooct-4-en-1-yl. Examples Cs-12-cycloalkenyl are cyclopent-3-en-1-yl, cyclohex-2-en-1-yl, cyclohex-3-en-1-yl, cyclohept-3-en-1-yl, cyclooct-4-en-1-yl, cyclonon-5-en-1- yl and cyclodec-5-en-1-yl.

[0025] Example of C4-8-heterocycloalkyl and of C4-i2-heterocycloalkyl are wherein R10is Ci- -alkyl.

[0026] The compound of formula (1) can be a single compound or a mixture of compounds. If the compound of formula (1) is a mixture of compounds, n refers to the average n.

[0027] Examples of n being 1.0 to 6.0 are 1.0, 1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 5.0 and 6.0. Examples of n being 1.0 to 4.0 are 1.0, 1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8 and 4.0. Examples of n being 1.0 to 2.0 are 1.0, 1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 and 2.0. Examples of n being 1.0 to 1.5 are 1.0, 1.1 , 1.2, 1.3, 1.4 and 1.5. Examples of n being 1.0 to 1.2 are 1.0, 1.1 and 1.2.

[0028] R1is preferably Cs-8-alkyl, Cs-8-alkenyl or Cs-s-alkinyl , more preferably Cs-6-alkyl and most preferably pentyl.

[0029] R2is preferably H.

[0030] In preferred compounds of formula (1) R1is Cs-8-alkyl and R2is H or methyl.

[0031] In more preferred compounds of formula (1) R1is pentyl and R2is H or methyl.

[0032] In most preferred compounds of formula (1) R1is pentyl and R2is H. n is preferably 1.0 to 4.0, more preferably 1.0 to 2.0, even more preferably 1.0 to 1.5, most preferably 1.0 to 1.2 and in particular 1.0. Also part of the present invention is a process for the preparation of the compound of formula wherein

[0033] R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein

[0034] C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s-cycloalkenyl or C4-8-heterocycloalkyl, and

[0035] Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl,

[0036] R2is H or methyl and n is 1.0 to 6.0, which process comprises the step of reacting a compound of formula wherein

[0037] R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein

[0038] C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s-cycloalkenyl or C4-8-heterocycloalkyl, and

[0039] Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, and n is 1.0 to 6.0, with a compound of formula wherein R2is H or methyl.

[0040] The equivalent ratio of COOH groups of the compound of formula (4) to OH groups of the compound of formula (3) is usually in the range of 0.90 / 1 .00 to 1 .20 / 1 .00, preferably in the range of 1.05 / 1.00 to 1.15 / 1.00.

[0041] The reaction of of the compound of formula (3) and the compound of formula (4) can be carried out in the presence or absence of solvent. Examples of suitable solvents include hydrocarbons such as n-heptane, cyclohexane, methylcyclohexane, toluene, ortho-xylene, meta-xylene, paraxylene, xylene isomer mixture, ethylbenzene, chlorobenzene, ortho- and meta-dichlorobenzene. Of further suitability as solvents in the absence of acidic catalysts are ethers such as dioxane or tetrahydrofuran, and ketones such as methyl ethyl ketone and methyl isobutyl ketone. Preferably, the reaction is carried out in the presence of solvent. More preferably, the reaction is carried out in the presence of a saturated hydrocarbon such as cyclohexane.

[0042] Preferably, the water formed over the course of the reaction is removed continuously during the reaction. Water can be removed by distillation. Water can also be removed by stripping with an inert gas or by performing the reaction in the presence of a water-removing agent such as MgSOt and Na2SO4. It is also possible to combine the described methods for removal of water. Preferably, water is removed by distillation, optionally in combination with other water- rem ova I methods.

[0043] Preferably the reaction is performed in the presence of at least one catalyst. The catalyst can be selected from the group consisting of acidic inorganic, acidic organic catalysts and organometallic catalysts. Preferably, one catalyst is used.

[0044] Examples of acidic inorganic catalysts are sulfuric acid, metal sulfates such as aluminium sulfate hydrate and alum, metal hydrogen sulfates such as sodium hydrogen sulfate, as well as acidic silica gel (pH <= 6, especially pH <= 5), acidic aluminium oxide, phosphoric acid, phos- phonic acid and hypophosphoric acid.

[0045] Examples of acidic organic catalysts are organic compounds containing phosphate groups, sulfonic acid groups, sulfate groups or phosphonic acid groups, such as para-toluene sulfonic acid. Further examples of acidic organic catalysts are acidic ion exchangers such as polystyrene resins being crosslinked with divinylbenzene and containing sulfonic acid groups.

[0046] Examples of organometallic catalysts are organic aluminium catalysts such as tris(n- butyloxy)aluminium, tris(isopropyloxy)aluminium and tris(2-ethylhexoxy)aluminium, as well as organic titanium catalysts such as titanium(IV) tetra(n-butoxide), titanium(IV) tetra(isopropoxide) and titanium(IV) tetra(2-ethylhexoxide), organic tin catalysts such as dibutyltin oxide, diphenyltin oxide, dibutyltin dichloride, tin(ll)di(n-octanoate), tin(ll) di(2-ethylhexanoate), tin(ll) laurate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dimaleate and dioctyltin diacetate as well as organic zinc catalysts such as zinc acetate.

[0047] The amount of all catalysts is usually in the range of 0.1 to 20%, preferably in therange of 1 to 10%, by weight based on the weight of compound (3) and compound (4).

[0048] Preferably, the reaction is carried out in the presence of at least one polymerization inhibitor.

[0049] Examples of polymerization inihibitors are copper(ll) chloride, 2,2,6,6-tetramethylpiperidine-1- oxyl (TEMPO), 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL), 4-benzoyloxy-2, 2,6,6- tetramethylpiperidine-1-oxyl, 4-benzyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 2,2-diphenyl-1- picrylhydrazyl (DPPH), tris(p-nitrophenyl)methane, p-phenylenediamines such as N,N'-diphenyl- p-phenylenediamine, phenothiazine, hydroxylamines such as N,N-diethylhydroxylamine DEHA), quinones such as hydroquinone (HQ), methyl hydroquinone, hydroquinone monomethyl ether (MEHQ), 1 ,4-benzoquinone, terf-butylhydroquinone, 2,5-bis(1 ,1,3,3-tetramethylbutyl)- hydroquinone and 2,5-bis(1,1-dimethylbutyl)hydroquinone, p-tert-butylcatechol (TBC), alkox- ylated phenols such as 4-methoxyphenol, alkylated phenols such as 2,6-di-terf-butylphenol, 2,4-di-tert-butylphenol, 2,4,6-tri-tert-butylphenol, 2-tert-butyl-4,6-dimethylphenol and 2,6-di-tert- butyl-4-methylphenol, alkylated and alkoxylated phenols such as 2-tert-butyl-4-methoxy phenol and 3-tert-butyl-4-methoxy phenol.

[0050] The reaction is usually performed at a temperature in the range of 60 to 150 °C, preferably at a temperature in the range of 80 to 120 °C.

[0051] The reaction can be monitored by determining the amount of water formed in the reaction, When the targeted amount of water formed in the reaction is reached, the reaction mixture is usually cooled to room temperature. Preferably any excess of the compound of formula (4) is removed by extraction with water. Then, usually any solvent present is removed by distillation, preferably under reduced pressure, to yield the compound of formula (1), which can be further purified by filtration.

[0052] The compound of formula wherein R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s-cycloalkenyl or C4-8-heterocycloalkyl, and Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, can be prepared in a process which comprises the steps of (i) reacting a compound of formula

[0053] O. <5> wherein

[0054] R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s-cycloalkenyl or C4-8-heterocycloalkyl, and Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, with formaldehyde to obtain a compound of formula wherein R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein

[0055] C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s-cycloalkenyl or C4-8-heterocycloalkyl, and

[0056] Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, and

[0057] (ii) reducing the compound of formula (6) to obtain the compound of formula (3”).

[0058] Step (ii) is usually performed in the presence of a reducing agent. Examples of reducing agents are formaldehyde and hydrogen.

[0059] If step (ii) is performed using formaldehyde as reducing agent, steps (i) and (ii) can be done in a “one-pot” process. The molar ratio of formaledehyde to compound (5) is in the range of 2 / 1 to 10 / 1 , preferably in the range of 2 / 1 to 8 / 1. Usually, formaldehyde is used as aqueous solution, and optionally one or more polar solvents such as cyclic or acyclic ether such as tetrahydrofuran, dioxane or methyl tert-butyl ether or alcohols such as methanol, ethanol or 2-ethyl hexanol can be present in the reaction mixture. The reaction is usually catalyzeded by a base. Examples of bases are tertiary amines such as trimethyl amine, triethylamine or tri(n-propy) amine or alkali metal hydroxides such as sodium or potassium hydroxide. The preferred base is an alkali metal hydroxide such as potassium or sodium hydroxide. The ratio of compound (5) to alkali metal hydroxide is usually in the range of 1.7 / 1 to 2.3 / 1. The reaction is usually performed at a temperature in the range of 15 to 80 °C. Compound (3”) can be obtained from the reaction mixture by extraction with a suitable solvent such as methyl tert-butyl ether.

[0060] Weibull, B. M., Magnus Acta Chem. Scand. 1962, 16, 1062 describes the preparation of 1 ,1 ,1- trishydroxymethylalkanes using formaldehyde as reducing agent.

[0061] If step (ii) is performed using hydrogen as reducing agent, steps (i) and (ii) are usually performed in distinct steps. In step (i) the molar ratio of formaldehyde to compound (5) is in the range of 2 / 1 to 6 / 1 , preferably in the range of 2 / 1 to 3 / 1 . Usually, formaldehyde is used as aqueous solution, and optionally one or more polar solvents such as cyclic or acyclic ether such as tetrahydrofuran, dioxane or methyl tert-butyl ether or alcohols such as methanol, ethanol or 2-ethyl hexanol can be present in the reaction mixture. The reaction is usually catalyzed by a base. Examples of bases are tertiary amines such as trimethyl amine, triethylamine or tri(n- propy) amine or alkali metal hydroxides such as sodium or potassium hydroxide. The preferred base is a tertiary amine such as trimethyl amine. The equivalent ratio of the aldehyde groups of compound (5) to tertiary amine groups of the tertiary amine is usually in the range of 5 / 1 to 1000 / 1 , preferably in the range of 6 / 1 to 100 / 1. Step (i) is usually performed at a temperature in the range of 15 to 80 °C. Un-reacted formaldehyde, the tertiary amine and / or un-reacted compound (5) can be removed by stripping with an inert gas. The obtained mixture comprising compound (6) and water can be used in step (ii).

[0062] Step (ii) using hydrogen as reducing agent is usually performed in the presence of a metal catalyst such as Fe, Ru, Os, Co, Rh, Ir. Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd and Hg. Prefered metal catalysts are Fe, Vo, Ni, Cu, Ru, Pd and Pt. The most preferred metal catalyst is copper. Copper is usually employed on a suitable carrier material such as titanium oxide, hafnium oxide, silicium dioxide or aluminium oxide. Step (ii) using hydrogen as reducing agent is usually performed in water. Step (ii) using hydrogen as reducing agent can be performed in a continuous or discontinuous manner. Step (ii) using hydrogen as reducing agent is usually performed at a temperature in the range of 50 to 180 °C, preferably at a temperature in the range of 90 to 140 °C. Step (ii) is usually performed at a pressure of 10 to 250 bar, preferably at a pressure of 20 to 120 bar, adjusted by the addition of hydrogen. Compound (3”) can be purified by distillation.

[0063] A similar process is described in WO2012143309A1. WO2012143309A1 describes the preparation of neopentyl glycol by a process which comprises (i) reacting isobutyraldehyde with formaldehyde to obtain hydroxypivaldehyde and (ii) reducing hydroxypivaldehyde with hydrogen to obtain neopentyl glycol.

[0064] Also part of the present invention is a process for preparation of the compound of formula (3”) as outlined above, wherein the reducing agent is hydrogen.

[0065] The compound of formula wherein

[0066] R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein

[0067] C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s-cycloalkenyl or C4-8-heterocycloalkyl, and Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, and n is greater than 1 .0 to 6.0. can be obtained as by-product in the process for the preparation of the compound of formula (3”) outlined above.

[0068] Examples of n greater than 1.0 to 6.0 are 1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 5.0 and 6.0. Preferably, n in the compound of formula (3*) is 1.1 to 6.0. Examples of n being 1.1 to 6.0 are 1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 5.0 and 6.0.

[0069] The compound of formula wherein

[0070] R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein

[0071] C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-8-cycloalkenyl or C4-8-heterocycloalkyl, and

[0072] Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, and n is greater than 1 .0 to 6.0 can also be prepared in a process which comprises the step of oligomerizing a compound of formula HO

[0073] H-O^^O H (3") R1wherein R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s-cycloalkenyl or C4-8-heterocycloalkyl, and Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl.

[0074] The oligomerization is usually performed in the presence of an acidic catalyst, preferably sulfuric acid. The amount of acid catalyst is usually 0.01 to 8.0%, and preferably 0.01 to 3.0% by weight by weight based on the weight of compound (3”).

[0075] The oligomerization is usually performed at elevated temperatures, usually at temperatures in the range of 80 to 220 °C, preferably at temperatures in the range of 120 to 220 °C.

[0076] Preferably, the water formed over the course of the reaction is removed continuously. Water can be removed by distillation. Distillation is usually performed at reduced pressure, such as at a pressure in the range of 0.1 to 200 mbar, preferably at a pressure of 0.1 to 50 mbar. Water can also be removed by stripping with an inert gas or by performing the reaction in the presence of a water-removing agent such as MgSO4and Na2SO4. It is also possible to combine the described methods for removal of water. Preferably, water is removed by distillation, optionally in combination with other water-removal methods.

[0077] The oligomerization of the compound of formula (3”) can be carried out in the presence or absence of a solvent. Examples of suitable solvents include hydrocarbons such as n-heptane, cyclohexane, methylcyclohexane, toluene, ortho-xylene, meta-xylene, para-xylene, xylene isomer mixture, ethylbenzene, chlorobenzene, ortho- and meta-dichlorobenzene. Preferred solvents form an azeotropic mixture with water.

[0078] The reaction can be monitored by determining the amount of water formed in the reaction, When the targeted amount of water formed in the reaction is reached, the reaction mixture is usually cooled to a temperature of below 120 °C, preferably below 100 °C. The reaction mixture can be neutralized by addition of a base such as aqueous sodium hydroxide solution. Then, usually any solvent and water present is removed by distillation, preferably under reduced pressure, to yield the compound of formula (3*). Also part of the present invention is a composition comprising at least one compound of formula (1), at least one oligomer or polymer (P) different from the compound of formula (1), which oligomer or polymer (P) is curable by radical polymerization, and optionally at least one radical initiator (I).

[0079] The oligomer or polymer (P) can be any oligomer or polymer different from the compound of formula (1) that can cure by radical polymerization.

[0080] The weight average molecular weight and the number average molecular weight of the oligomer or polymer (P) is preferably in the range of 450 to 500000 g / mol, more preferably in the range of 450 to 50000 g / mol, even more preferably in the range of 500 to 20000 g / mo and most preferably in the range of 500 to 8000 g / mol. The weight average molecular weight and the number average molecular weight can be determined using gel permeation chromatography calibrated to a polystyrene standard.

[0081] The oligomer or polymer (P) is preferably an oligomer or polymer that can cure by radical polymerization and that carries or comprises at least one group, preferably two groups, selected from the group consisting of wherein R3, R4and R5are independently from each other H or methyl, preferably H, and R6is H or Ci-2o-alkyl. Examples of oligomer or polymer (P) are polyurethanes, acrylic resins, hybrids of polyurethane and acrylic resins, polyesters, polyamide, polyurea, polysiloxanes, polyethers, polycarbonates, epoxy-resins, resins derived from epoxy-resins, alkyd resins, polyolefins and polyvinylacetates that can cure by radical polymerization and carry or comprise at least one group, preferably two groups, selected from the group consisting of wherein R3, R4and R5are independently from each other H or methyl, preferably H, and R6is H or Ci-2o-alkyl.

[0082] Polyurethanes are oligomers or polymers comprising urethane linkages. Polyurethanes are usually obtained by reaction of diols with diisocyanates. The diol can be a polyester diol, acrylic polymer diol, polycarbonate diol or polyetherdiol. Polyurethanes may comprise further linking groups in the main chain in lower number than the number of urethane groups such as ester, ether, thioether or urethane linkages.

[0083] Acrylic resins are oligomers or polymers obtainable by radical polymerization from polymerizable unsaturated monomers comprising acrylic acid esters or methacrylic acid esters, and optionally other polymerizable unsaturated monomers, by methods known in the art such as emulsion polymerization. Examples of other polymerizable unsaturated monomers are polymerizable unsaturated monomers carrying OH groups such as 2-hydroxyethyl (meth)acrylate, 2-hydroxy- propyl (meth)acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxy butyl (meth)acrylate and (meth)allyl alcohol, and polymerizable unsaturated monomers carrying acidic groups such as acrylic acid, methacrylic acid, maleic acid, citraconic acid, itaconic acid, maleic anhydride, citraconic anhydride and itaconic anhydride. Hybrids of polyurethane and acrylic resins can be obtained, for example, by preparing the acrylic resin as described above, but in the presence of a polyurethane.

[0084] Polyesters are oligomers or polymers comprising monomers linked via an ester linkage. Polyesters are usually obtained by an esterification reaction or transesterification reaction of a component carrying two acidic groups and a diol. Polyesters may comprise further linking groups in the main chain in lower number than the number of ester groups such as amide, urea, carbonate, ether, thioether or urethane linking groups.

[0085] Polyamides are oligomers or polymers comprising monomers linked via an amide linkage. Polyamides are usually obtained by a condensation reaction of a component carrying two acidic groups and a diamine. Polyamides may comprise further linking groups in the main chain in lower number than the number of amide groups such as ester, urea, carbonate, ether, thioether or urethane linking groups.

[0086] Polyureas are oligomers or polymers comprising monomers linked via a urea linkage. Polyureas are usually obtained by reaction of diamines with diisocyanates. Polyureas may comprise further linking groups in the main chain in lower number than the number of urea groups such as ester, amide, carbonate, ether, thioether or urethane linking groups.

[0087] Polyethers are oligomers or polymers comprising ether linkages. Polyethers are usually prepared by acid catalyzed polymerization of ethers such as ethyleneoxide, propylene oxide, butylene oxide or tetrahydrofuran using an alcohol. Examples of polyethers are polyoxyethylene polyether, polyoxypropylene polyether, polyoxybutylene polyether and polytetrahydrofuran. Polyethers may comprise further linking groups in the main chain in lower number than the number of ether groups such as ester, amide, urea, carbonate, thioether or urethane linkages.

[0088] Polycarbonates are oligomers or polymers comprising carbonate linkages. Polycarbonates are usually obtained by reaction of carbonates with diols. Polycarbonates may comprise further linking groups in the main chain in lower number than the number of carbonate groups such as ester, amide, urea, ether, thioether or urethane linkages.

[0089] Epoxy resins are oligomers or polymers carrying at least one, preferably at least two, epoxy groups. An example of an epoxy resin is bisphenol A diglycidyl ether resin obtainable by first reacting bisphenol A with epichlorohydrin followed by dehydrohalogenation to give bisphenol A diglycidyl ether monomer, and subsequent polymerization of the bisphenol A diglycidyl ether monomer with bisphenol A. A further example of an epoxy resin is the product of a novolak resin, which are polymers formed by reaction of phenol with formaldehyde, with epichlorohydrin.

[0090] Resins derived from epoxy resins are oligomers or polymers that are obtainable by the reaction of the epoxy group of an epoxy resin with another compound such as acrylic or methacrylic acid. Alkyd resins are polyester carrying fatty acid-derived groups. Alkyd resins are usually obtained by an esterification reaction or transesterification reaction of a component carrying two acidic groups, a polyol and a glycerine fatty acid triester. Examples of components carrying two acidic groups are phthalic anhydride and maleic anhydride. Examples of polyols are trimethylolpropane, glycerine and pentaeryhritol. Examples of glycerine fatty acid triester are soybean oil, linseed oil and coconut oil.

[0091] Polyolefins are oligomers or polymers obtainable by polymerizing at least one olefin monomer, optionally in the presence of at least a polymerizable unsaturated monomer which is not an olefin monomer, by methods known in the art such as emulsion polymerization. Olefin monomers are monomers comprising solely H and C atoms. Examples of olefin monomers are ethylene, propylene, 1 -butene, 3-methyl-1 -butene, 4-methyl-1 -pentene, 3-methyl-1 -pentene, 1 -heptene, 1 -hexene, 1 -decene and 1 -dodecene; conjugated dienes and non-conjugated dienes such as butadiene, ethylidene norbornene, dicyclopentadiene and 1 ,5-hexadiene, and styrenes. Examples of polymerizable unsaturated monomers, which are no olefin monomers, are vinyl acetate, vinyl alcohol, maleic acid, citraconic acid, itaconic acid, maleic anhydride, citraconic anhydride and itaconic anhydride.

[0092] The oligomer or polymer (P) is commercially available or can be prepared by methods known in the art.

[0093] For example, oligomers or polymers (P) which carry at least one group of formula wherein R3is H or methyl, and R4and R5are H, can be prepared by esterifying at least one OH group of a polymeric precursor with acrylic acid or methacrylic acid, by ring opening the epoxy group of an epoxy polymer with acrylic acid or methacrylic acid or by preparing the oligomer or polymer (P) using monomers already carrying the group of formula (10).

[0094] The oligomer or polymer (P) is more preferably an oligomer or polymer that can cure by radical polymerization and that carries at least one group, preferably at least two groups, of formula wherein R3is H or methyl, preferably H.

[0095] The oligomer or polymer (P) is even more preferably is an oligomer or polymer carrying at least one group, preferably at least two groups, of formula

[0096] (11")

[0097] (11*) wherein R3is H or methyl, preferably H.

[0098] The oligomer or polymer (P) is most preferably at least one oligomer or polymer selected from the group consisting of wherein L1is an organic residue, R3is H or methyl, and m is 0 to 16.0.

[0099] The oligomer or polymer of formula (2#), (2”) and (2*), respectively, can be a single oligomer or polymer or a mixture of oligomers or polymers. If the oligomer or polymer of formula (2#), (2”) and (2*), respectively, is a mixture of oligomers or polymers, m refers to the average m.

[0100] Examples of m being 0 to 16.0 are 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 , 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 8.0, 10.0, 12.0, 14.0 and 16.0. Examples of m being 0.1 to 16.0 are 0.1 , 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1 , 2.2, 2.4, 2.6,

[0101] 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 8.0, 10.0, 12.0, 14.0 and 16.0. Examples of m being 0.2 to 10.0 are 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 , 1.2, 1.3, 1.4, 1.5,

[0102] 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5,

[0103] 7.0, 8.0 and 10.0. Examples of m being 0.3 to 5.0 are 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1 , 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.5 and

[0104] 5.0. Examples of m being 0.4 to 3.0 are 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 , 1.2, 1.3, 1.4, 1.5,

[0105] 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.4, 2.6, 2.8 and 3.0. Examples of m being 0.5 to 1.5 are 0.5,

[0106] 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 , 1.2, 1.3, 1.4 and 1.5,

[0107] R3is preferably H, m is preferably 0.1 to 16.0, more preferably 0.2 to 10.0, even more preferably 0.3 to 5.0, most preferably 0.4 to 3.0, and in particular from 0.8 to 1.5.

[0108] L1can be any organic residue. L1is preferably selected from the group consisting of

[0109] L1is more preferably

[0110] In preferred oligomers or polymers of formula (2),

[0111] R3is H, m is 0.1 to 16.0, preferably 0.2 to 10.0, even more preferably 0.3 to 5.0, most preferably 0.4 to 3.0, and in particular from 0.8 to 1.5, L1is

[0112] The oligomer or polymer of formula (2#), (2”) and (2*), respectively, as well as mixtures of at least two oligomers or polymers selected from the group consisting of (2#), (2”) and (2*) are also referred as oligomer or polymer of formula (2).

[0113] In oligomer (2a) of example 4, R3is H, L1is a group of formula (12) and m is 1.1.

[0114] An oligomer or polymer which is at least one oligomer or polymer selected from the group consisting of wherein

[0115] R3is H or methyl,

[0116] L1is an organic residue, and m is 0 to 16.0 can be obtained by reacting an oligomer or polymer of formula wherein

[0117] L1is an organic residue, and m is 0 to 16.0 with a compound of formula wherein R3is H or methyl.

[0118] The reaction is usually performed in the presence of a catalyst. Examples of catalysts are tertiary amines, quaternary ammonium salts, trialkylphosphines, triarylphosphines, dialkylarylphosphines, diarylalkylphosphines and heteroaromatic compounds comprising at least one N as heteroatom.

[0119] Examples of tertiary amines are tributylamine, 1 ,4-diazabicyclo[2.2.2]octane, N-methyl- morpholine, N-ethyl-morpholine, bis[2-(N,N-dimethylamino)ethyl] ether, 2,2’-dimorpholinyl- diethylether, N,N,N',N'-tetramethylethylenediamine, N,N-dimethylcyclohexylamine, N,N- dimethylphenylamine, N,N-dimethylbenzylamine, N,N- dimethylethanolamine, 1 , 1 ,3,3-tetra- methylguanidine, 1 ,5-diazabicyclo[4.3.0]non-5-ene (DBN) and 1 ,8-diazabicyclo[5.4.0]undec-7- ene (DBU).

[0120] Examples of quaternary ammonium salts are tetraethylammonium bromide, tetrabutylammonium bromide and N,N,N-trimethylbenzylammonium bromide.

[0121] An example of a triarylphosphine is triphenylphosphine.

[0122] Examples of heteroaromatic compounds comprising at least one N as heteroatom are pyridine, quinoline, isoquinoline, 2-ethyl imidazole, N-methyl imidazole and N-butyl imidazole. The weight ratio of amine catalyst to oligomer (7) and compound (4) is preferably 1 to 20%, more preferably 2 to 10%.

[0123] The reaction can be performed in the presence of absence of solvent. Preferably, the reaction is performed in the absence of solvent.

[0124] The reaction is usually performed at a temperature in the range of 50 to 150 °C, preferably in the range of 80 to 120 °C.

[0125] The reaction is usually performed in the presence of a polymerization inihibitor.

[0126] Examples of polymerization inihibitors are copper(ll) chloride, 2,2,6,6-tetramethylpiperidine-1- oxyl (TEMPO), 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL), 4-benzoyloxy-2, 2,6,6- tetramethylpiperidine-1-oxyl, 4-benzyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 2,2-diphenyl-1- picrylhydrazyl (DPPH), tris(p-nitrophenyl)methane, p-phenylenediamines such as N,N'-diphenyl- p-phenylenediamine, phenothiazine, hydroxylamines such as N,N-diethylhydroxylamine DEHA), quinones such as hydroquinone (HQ), methyl hydroquinone, hydroquinone monomethyl ether (MEHQ), 1 ,4-benzoquinone, terf-butylhydroquinone, 2,5-bis(1 ,1 ,3,3-tetramethylbutyl)- hydroquinone and 2,5-bis(1 ,1-dimethylbutyl)hydroquinone, p-tert-butylcatechol (TBC), alkox- ylated phenols such as 4-methoxyphenol, alkylated phenols such as 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, 2,4,6-tri-tert-butylphenol, 2-tert-butyl-4,6-dimethylphenol and 2,6-di-tert- butyl-4-methylphenol, alkylated and alkoxylated phenols such as 2-tert-butyl-4-methoxy phenol and 3-tert-butyl-4-methoxy phenol.

[0127] The reaction can be monitired by the determination of the acid value of the reaction mixture.

[0128] The oligomer or polymer of formula wherein

[0129] L1is an organic residue, and m is 0 to 16.0 is commercially available or can be prepared by methods known in the art, for example by the polymerization of the compound of formula wherein

[0130] L1is an organic residue, with a compound of formula

[0131] HO-l1-O H(9) wherein

[0132] L1is an organic residue.

[0133] The radical initiator (I) can be any compound that forms free radicals upon heat treatment (thermal radical initiator) or upon radiation (photoinitiator).

[0134] Examples of thermal radical initiators are peroxides such as potassium persulfate, dibenzoyl peroxide, cyclohexanone peroxide, di-tert-butyl peroxide, acetyl cyclohexylsulfonyl peroxide, di- / so-propyl percarbonate, tert-butyl peroctoate, cumene hydroperoxide, dicumyl peroxide and tert-butyl perbenzoate, azobis- / so-butyronitrile and benzpinacol.

[0135] Examples photoinitiators are acetophenone, 2,2-dimethoxy-2-phenylacetophenone (benzil dimethyl ketal), 2,2-diethoxyacetophenone, 4-dimethylaminoacetophenone, benzophenone, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone 4-hydroxybenzophenone, 4-phenylbenzophenone, 2-chlorobenzophenone, 4,4'-bis(diethylamino)benzophenone, thioxanthone, isopropyl-9H-thioxanthen-9-one, phenyl glyoxylic acid methyl ester, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin n-propylether, benzoin isopropylether, benzoin n- butyl ether, benzoin isobutyl ether, benzoin dimethyl ketal, cyclohexyl phenyl ketone, 1-hydroxy- cyclohexyl phenyl ketone, p-isopropyl-2-hydroxyisobutyrophenone, 2-hydroxy-2-methyl-1- phenyl-1 -propanone, oligo[2-hydroxy-2-methyl-1-[ 4-(1-methylvinyl)phenyl]propanone], 2- benzyl-2-dimethylamino 1-(4-morpholinophenyl) butanone-1 , 2-benzyl-2-dimethylamino-1-(4- morpholinophenyl)-1-butanone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 4- (2-hydroxyethoxy)phenyl 2-hydroxy-2-propyl ketone, acylphosphine oxides such as diphe- nyl(2,4,6-trimethylbenzoyl) phosphine oxide, phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide and bis(2,6-dimethoxybenzoyl)-2,4,4 trimethylpentylphosphine oxide, methyl-2-benzoyl benzoate and ethyl phenyl(2,4,6-trimethylbenzoyl) phosphinate.

[0136] It is also possible to use mixtures of initiators. Examples of mixtures of initiators are mixtures of at least two photoinitiators, mixtures of at least one photoinititiator and at least one thermal radical initiator as well as mixtures of at least two thermal radical initiators. Common mixtures of photoinitiators are the mixture of bis(2,6-dimethoxybenzoyl)-2,4,4 trimethylpentylphosphine oxide and 2-hydroxy-2-methyl-1-phenyl-1 -propanone, the mixture of 1- hydroxycyclohexyl phenyl ketone and benzophenone, the mixture of bis(2,6-dimethoxybenzoyl)- 2,4,4-trimethylpentylphosphine oxide and 1-hydroxy-cyclohexyl phenyl ketone, the mixture of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide and 2-hydroxy-2-methyl-1-phenyl-1- propanone, the mixture of 2,4,6-trimethylbenzophenone and 4-methylbenzophenone, and the mixture of 4-methylbenzophenone and diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide.

[0137] The at least one initiator is preferably a photoinitiator, more preferably a UV photoinitiator. A UV photoinitiator is an initiator that forms free radicals upon UV radiation treatment. Preferred initiators are selected from the group consisting of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, ethyl phenyl (2,4,6-trimethylbenzoyl) phosphinate, benzophenone, phenyl bis(2,4,6- tri methyl benzoyl) phosphine oxide, 1-hydroxy-cyclohexyl phenyl ketone, 2-hydroxy-2-m ethyl- 1- phenyl-1 -propanone and 2,2-dimethoxy-2-phenylacetophenone (benzil dimethyl ketal).

[0138] The composition can also comprise further additives such as reactive diluents (R) different than the compound of formula (1) and the oligomer or polymer (P), polymerization inihibitors, thickeners, ultraviolet absorbers, light stabilizers, surfactants, photosensitizers, curing catalyst, antifoamers, plasticizers, fillers, pigments, dyes, flow control agents, antioxidants, flame retardents, antistatic agents, thixotropic agents, leveling agents, tackifiers, chelating agents, matting agents and compatibilizers.

[0139] Examples of reactive diluents (R) different than the compound of formula (1) and the oligomer or polymer (P) are styrene, p-tert-butylstyrene, p-methylstyrene, o-methylstyrene, 2-vinyl- naphthalene, divinylstyrene, butadiene, isoprene, chloroprene, ethylene, propylene, 1 -butene, 2-butene, isobutene, cylopentene, cyclohexene, cyclododecene, vinyl acetate, vinyl propionate, vinyl chloride and vinylidene chloride, N-vinyl formamide, N-vinylacetamide, N-vinyl-N-methyl formamide, N-vinyl-N-methyl-acetamide, N-vinyl pyrrolidone, N-vinyl caprolactam, ethylene glycol divinyl ether, di(ethylene glycol) divinyl ether, tri(ethylene glycol) divinyl ether, trimethylolpropane trivinyl ether, 1 ,4-cyclohexanedimethanol divinyl ether, methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, isobutyl vinyl ether, tert-amyl vinyl ether, dodecyl vinyl ether, 1 ,4-butanediol divinyl ether, 1 ,6-hexanediol divinyl ether, cyclohexyl vinyl ether, allyl acetate, diallyl phthalate, triallylcyanurate, trimethylolpropane triallyl ether, alpha, beta unsaturated C4- -dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid and 2-methylenglutaric acid as well as salts thereof, esters of alpha, beta unsaturated C4- -dicarboxylic acids such as dimethyl ester of maleic acid, ethyl methyl ester of maleic, diethyl ester of maleic acid, dimethyl ester of fumaric acid, the ethyl methyl ester of fumaric acid and the diethyl ester of fumaric acid, alpha, beta unsaturated nitriles such as (meth)acrylonitrile, and alpha, beta unsaturated aldehydes such as (meth)acrolein, and alpha, beta unsaturated amides such as (meth)acrylamide, alpha, beta unsaturated Cs-s-carboxylic acids such as acrylic acid, methacrylic acid and 3,3-dimethyl acrylic acid as well as salts thereof.

[0140] Further examples of reactive diluents (R) different than than the compound of formula (1) and the oligomer or polymer (P) are Ci-2o-alkyl(meth)acrylate such as methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, butyl(meth)acrylate, isobutyl(methacrylate), sec- butyl(meth)acrylate, tert-butyl(meth)acrylate, pentyl(meth)acrylate, isopentyl(meth)acrylate, 2- methylbutyl(meth)acrylate, amyl(meth)acrylate, hexyl(meth)acrylate, 2-ethylbutyl(meth)acrylate, heptyl(methacrylate, octyl (meth)acrylate, 2-ethylhexyl(meth)acrylate, 2-propylheptyl- (meth)acrylate, nony(meth)acrylate), decyl(methacrylate), isodecyl(methacrylate), un- decyl(meth)acrylate and dodecyl(meth)acrylate, tridecyl (meth)acryte, tetradecyl(meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate and nonadecyl(meth)acrylate, Cs-i2-cycloalkyl(meth) acrylate such as cyclopen- tyl(meth)acrylate, cyclohexyl(meth)acrylate and cycloheptyl (meth)acrylate, acetoacetoxy(C2-6- alkyl) (meth)acrylates such as acetoacetoxyethyl (meth)acrylate, acetoacetoxypropyl (meth)acrylate and acetoacetoxybutyl (meth)acrylate, [Ci-io-alkoxy(Ci-io-alkoxy)o-s]Ci-io- alkyl(methacrylate) such as 2-methoxyethyl(meth)acrylate, 2-ethoxyethyl(meth)acrylate, 4- methoxybutyl(meth)acrylate, 2-(2’-methoxyethoxy)ethyl(meth)acrylate and 2-(2’-ethoxy- ethoxy)ethyl(meth)acrylate, 2-norbonyl (meth)acrylate, dihydrodicyclopentadienyl (meth)acrylate, 4-tetrahydropyranyl (meth)acrylate, 2-tetrahydropyranyl (meth)acrylate, tetrahydrofuryl (meth)acrylate, diesters of Ci-20-diols with (meth)acrylic acid such as 1 ,2-ethyleneglycol di(meth)acrylate, 1 ,2-propyleneglycol di(meth)acrylate, 1 ,3-propyleneglycol di(meth)acrylate, 1 ,2-butanediol di(meth)acrylate, 1 ,3-butanediol-di(meth)acrylate, 1 ,4-butanediol di(meth)acrylate, neopentylglycol di(meth)acrylate, 1 ,6-hexanediol di(meth)acrylate, 1 ,7- heptandiol di(methacrylate), 1 ,8-octanediol di(methacrylate), 1 ,9-nonanediol di(meth)acrylate, 1 ,10-decanediol di(methacrylate), 1 ,2-bis(hydroxymethyl)-cyclohexane di(methacrylate), 1 ,4- bis(hydroxymethyl)-cyclohexane di(methacrylate and cyclohexan-1 ,4-diol di(meth)acrylate, diesters of ethoxylated and / or propoxylated Ci-20-diols with (meth)acrylic acid such ethoxylated and / or propoxylated 1 ,2-butanediol di(meth)acrylate, ethoxylated and / or propoxylated 1 ,4- butanediol di(meth)acrylate, ethoxylated and / or propoxylated neopentylglycol di(methacrylate), ethoxylated and / or propoxylated 1 ,4-bis(hydroxymethyl)-cyclohexane di(methacrylate), diethyleneglycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate as well as polyethylene glycols di(methacrylate), polypropylene glycols di(meth)acrylate, polyethylene-polypropylene glycol di(meth)acrylate, the sequence of the ethylene oxide or propylene oxide units being blockwise or random, polytetramethyleneglycol di(meth)acrylate, polytetrahydrofurane di(meth)acrylate, and ethoxylated or propoxylated bisphenol A di(methacrylate), glycerol tri(meth)acrylate, 1 ,1 ,1 -trimethylolpropane tri(meth)acrylate, 1 ,1 ,1 -trimethylolethane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, di(1 , 1 ,1 -trimethylolpropane) tetra(meth)acrylate and dipentaerythritol hexa(meth)acrylate, ethoxylated and / or propoxylated glycerol tri(meth)acrylate, ethoxylated and / or propoxylated 1 ,1 ,1- trimethylolpropane tri(meth)acrylate, ethoxylated and / or propoxylated pentaerythritol tet- ra(meth)acrylate, ethoxylated and / or propoxylated di(1 , 1 ,1 -trimethylolpropane) tet- ra(meth)acrylate and ethoxylated and / or propoxylated dipentaerythritol hexa(meth)acrylate.

[0141] The term “(meth)acryloyl” comprises acryloyl and methacryolyl.

[0142] The reactive diluent (R) different than the compound of formula (1) and the oligomer or polymer (P) has preferably a weight average molecular weight of below 1000 g / mol and a number average molecular weight of below 750 g / mol. The weight average molecular weight and the number average molecular weight can be determined using gel permeation chromatography calibrated to a polystyrene standard.

[0143] Examples of polymerization inihibitors are copper(ll) chloride, 2,2,6,6-tetramethylpiperidine-1- oxyl (TEMPO), 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL), 4-benzoyloxy-2, 2,6,6- tetramethylpiperidine-1-oxyl, 4-benzyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, 2,2-diphenyl-1- picrylhydrazyl (DPPH), tris(p-nitrophenyl)methane, p-phenylenediamines such as N,N'-diphenyl- p-phenylenediamine, phenothiazine, hydroxylamines such as N,N-diethylhydroxylamine DEHA), quinones such as hydroquinone (HQ), methyl hydroquinone, hydroquinone monomethyl ether (MEHQ), 1 ,4-benzoquinone, terf-butylhydroquinone, 2,5-bis(1 ,1,3,3-tetramethylbutyl)- hydroquinone and 2,5-bis(1,1-dimethylbutyl)hydroquinone, p-tert-butylcatechol (TBC), alkox- ylated phenols such as 4-methoxyphenol, alkylated phenols such as 2,6-di-terf-butylphenol, 2,4-di-tert-butylphenol, 2,4,6-tri-tert-butylphenol, 2-tert-butyl-4,6-dimethylphenol and 2,6-di-tert- butyl-4-methylphenol, alkylated and alkoxylated phenols such as 2-tert-butyl-4-methoxy phenol and 3-tert-butyl-4-methoxy phenol.

[0144] Examples of thickeners are hydroxymethyl cellulose and bentonite. Examples of ultraviolet absorbers are benzotriazoles such as 2-(3-terf-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzo- triazole, 2-(2H-benzotriazol-2-yl)-4-(1 ,1 ,3,3-tetramethylbutyl) phenol and 2-(2H-benzotriazol-2- yl)-p-cresol, triazines such as 2-(4,6-diphenyl-1,3,5-triazin-2-yl)5-((hexyl)oxy) phenol), cyanoacrylates and benzophenones. Examples of light stabilizers are hindered amine light stabilizers (HALS) such as 2,2,6,6-tetramethylpiperidine, 2,6-di-tert-butylpiperidine and bis(2, 2,6,6- tetramethyl-4-piperidyl) sebacate. Examples of fillers are talc, siliceous earth, clay, aluminium silcates, magnesium silicate, calcium carbonate, calcium sulfate, barium sulfate, aluminium hydroxide aluminium oxide and organic fillers such as polyacrylic acid and cellulose. Examples of chelating agenst are ethylenediamine tetraacetic acid and p-diketones.

[0145] The composition of the present invention usually comprises 10.0 to 98.0% by weight of the compound of formula (1 ) and 2.0 to 90.0% by weight of oligomer or polymer (P) based on the weight of the composition. The composition of the present invention preferably comprises

[0146] 25.0 to 96.0% by weight of the compound of formula (1) and

[0147] 4.0 to 75.0% by weight of oligomer or polymer (P) based on the weight of the composition.

[0148] The composition of the present invention more preferably comprises

[0149] 40.0 to 95.0% by weight of the compound of formula (1) and

[0150] 5.0 to 60.0% by weight of oligomer or polymer (P) based on the weight of the composition.

[0151] The composition of the present invention usually comprises 0 to 20.0% by weight of radical initiator (I) based on the weight of the compound of formula (1) and of the oligomer or polymer (P).

[0152] The composition of the present invention preferably comprises 0.1 to 15.0% by weight of radical initiator (I) based on the weight of the compound of formula (1) and of the oligomer or polymer (P).

[0153] The composition of the present invention more preferably comprises 1.0 to 10.0% by weight of radical initiator (I) based on the weight of the compound of formula (1) and of the oligomer or polymer (P).

[0154] The composition preferably comprises below 5 weight%, more preferably below 2 weight% and most preferably below 1%, water, based on the weight of the composition.

[0155] The composition preferably comprises below 10 weight%, more preferably below 5 weight%, even more preferably below 2 weight% and most preferably below 1%, organic solvent based on the weight of the composition.

[0156] The composition of the present invention can be prepared by mixing the compound of formula (1) with the oligomer or polymer (P), the radical initiator, if present, and additives, if present, in any order.

[0157] Also part of the present invention is a cured layer formed from the composition of the present invention.

[0158] The cured layer is obtainable by a process, which comprises the steps of (i) applying the composition of the present invention to a substrate to form a layer, and (ii) treating the layer of step (i) with heat, radiation or electron beam to form a cured layer. The compositions of the present invention can be applied to the substrate by any method known in the art such as by draw down bar, spraying, troweling, knifecoating, brushing, rolling, rollercoating, flowcoating and laminating, doctor blades, various printing processes such as gravure, transfer, lithographica and ink jet printing and by using a bar.

[0159] The layer obtained directly after application of the composition on the substrate has preferably a thickness in the range of 20 to 500 micrometer, more preferably in the range of 40 to 300 micrometer, most preferably in the range of 60 to 240 micrometer, and in particular 60 to 200 micrometers.

[0160] The layer of step (i) is treated in step (ii) with electron beam, heat or radiation to form a crosslinked layer. Heat can be applied by any suitable heat source, including near infrared (NIR) radi- tion, for example radiation having a wavelength in the range of 760 to 2500 nm. Preferably, the layer of step (i) is treated with ultraviolett radiation, daylight or electron beam. More preferably, the layer of step (i) is treated with radiation having a wavelength in the range of 200 to 700 nm, even more preferably in the range of fro 200 to 500 nm, and most preferably in the range of 250 to 400 nm.

[0161] Examples of radiation sources are low-pressure mercury vapor lamps, medium-pressure mercury vapor lamps, high-pressure mercury vapor lamps, lasers, pulsed lamps (flashlight), halogen lamps, excimer lamps and LED lamps including IIV-A LED, UV-B LED and UV-C LED lamps. The radiation dose is normally chosen to be sufficient for curing. In case of UV radiation, a radiation dose of 80 to 3000 mJ / cm2, preferably 100 to 2000 mJ / cm2is usually used. A combination of different radiation sources is also possible.

[0162] Step (ii) can be perfomed either in the presence of oxygen or in the absence of oxygen such as under intert gas atmosphere. Suitable inert gases are nitrogen, argon and carbon dioxide. The layer of step (i) can also be covered with transparent media such as a transparent polymer film, glas or water and irradiated through the transparent media. Irradation can also be performed by passing the substrate coated with the layer of step (i) at constant speed past a radiation source.

[0163] The substrate can be any suitable substrate. Preferably, the substrate is selected from the group consisting of wood substrates, engineered wood substrates, engineered bamboo substrates, engineered cellulosic substrates other than engineered wood or bamboo substrates, fibre-reinforced composite substrates (FRC), wood-plastic composite substrates (WPG), plastic substrates such as melamine formaldehyde substrate, paper substrates, recycled paper substrates, paperboard (also called cardboard) substrate, recycled paperboard (also called recycled cardboard) substrates, metal substrates, stone substrate, glass substrates, textiles substrates, leather substrates, ceramic substrates, mineral building material substrates such as molded cement blocks and fiber-cement slabs. The substrates can also be precoated with a coating composition different from the coating composition of the present invention. Examples of wood substrates are oak, beech, maple, alder, ash, pine tree, fir tree, spruce, chestnut, robinia, birch, elm, teak and walnut as well as cork.

[0164] Wood can, for example, be in the form of lumber (also called timber), in the form of planks used for flooring, for example parquet flooring, in the form of devices used for house construction or domestic applications, or in the form of solid wood furnitures. Cork can be, for example, in the form of tiles used for flooring, or in the form of devices used for domestic applications.

[0165] Engineered wood substrates are derivative wood substrates manufactured by binding or fixing the strands, particles, fibres, veneers or boards of wood with adhesives or other methods of fixation to form composite materials. Examples of adhesives are urea-formaldehyde resin, phenol formaldehyde resin, melamine formaldehyde resin, polymeric methylene diphenyl diisocyanate, polyvinyl acetate and polyurethane. Examples of engineered wood substrates are glue- laminated timber, cross-laminated timber (CLT), parallel strand lumber (PSL), laminated strand lumber (LSL), laminated veneer lumber (LVL), plywood, oriented strand board (OSB), composite panels, particle board (also called flakeboard or chipboard), fibreboard such as hardboard (also called high-density fibreboard, HDF) and medium density fibreboard (MDF).

[0166] Engineered wood substrates can be in the form of lamella used for engineered wood flooring, for example laminate flooring, in the form of devices used for house construction or domestic applications, and in the form of furniture such as flat-pack furniture.

[0167] Engineered bamboo substrates are derivative bamboo substrates manufactured by binding or fixing parts of bamboo with adhesives or other methods of fixation to form composite materials. An example of engineered bamboo substrate is laminated bamboo.

[0168] Engineered cellulosic substrates other than engineered wood substrates and bamboo substrates are products from lignin-containing materials other than wood and bamboo such as rye straw, wheat straw, rice straw, hemp stalks, kenaf stalks and sugar cane residue, manufactured by binding or fixing parts of the lignin-containing materials other than wood and bamboo with adhesives or other methods of fixation to form composite materials.

[0169] Fibre-reinforced composite substrates (FRC) are made from rice-derived fibres and plastic.

[0170] Wood-plastic composites (WPCs) are composite materials made from fibres or flour of wood and thermoplastic polymers such as polyethylene, prolypropylene, polyvinyl chloride or polyacetic acid.

[0171] More preferably, the substrate is selected from the group consisting of wood substrates, engineered wood substrates, engineered cellulosic substrates other than engineered wood or bam- boo substrates, fibre-reinforced composite substrates (FRC), wood-plastic composite substrates (WPC), plastic substrates such as melamine formaldehyde substrate, paper substrates, recycled paper substrates, paperboard (also called cardboard) substrate, recycled paperboard (also called recycled cardboard) substrates, metal substrates, glass substrates, ceramic substrates.

[0172] Most preferably, the substrate is selected from the group consisting of wood substrates, engineered wood substrates and wood-plastic composite substrates (WPC).

[0173] Preferably, the substrate is flat and has an even surface.

[0174] Also part of the present invention is a substrate coated with the cured layer of the present invention.

[0175] Also part of the present invention is the use of the coating composition of the present invention as paint or varnish composition.

[0176] The reactive diluent of the present invention is advantageous as curable compositions comprising the reactive diluent of the present invention and at least one oligomer or polymer (P) curable by radical polymerization are of acceptable viscosity and at the same time form cured layers with no or or only not-significant variations in the hardness of the cured layer over a wide range of ratios of oligomer or polymer (P) curable by radical polymerization to reactive diluent.

[0177] Examples

[0178] Irgacure 184: 1-hydroxy-cyclohexyl phenyl ketone

[0179] Example 1

[0180] Preparation of compound 3a n-Heptanal (91.4 g, 0.8 mol) and aqueous formaldehyde solution (37%, 487.0 g, 6.0 mol) were stirred for one hour at room temperature. Afterwards, potassium hydroxide (44.8 g, 0.4 mol) was dissolved in water (200 mL) and added dropwise, while cooling the reaction mixture in an icebath reaching a maximal temperature of 27 °C. The reaction mixture was stirred for three hours at room temperature, followed by two hours at 50 °C and further 12 hours at room temperature. The biphasic mixture was extracted using methyl tert-butyl ether. The combined organic phases were washed with water, dried over anhydrous magnesium sulfate, filtered and concentrated. Compound 3a was obtained as a colorless solid (yield: 27.0%) after purification by vacuum distillation and recrystallization from methyl tert-butyl ether and cyclohexane.1H NMR (500 MHz, DMSO-d6): 5 0.86 (t, 3H), 1.10-1.40 (m, 8H), 3.25 (d, 6H), 4.20 (s, 3H) ppm.13C NMR (125 MHz, DMSO-d6): 5 13.9, 21.9, 22.1, 29.1 , 32.5, 43.2, 62.1 ppm.

[0181] Example 2

[0182] Preparation of compound 3b n-Nonanal (113.0 g, 0.8 mol) and aqueous formaldehyde solution (37%, 245.0 g, 3.0 mol) were stirred for one hour at room temperature. Afterwards, potassium hydroxide (44,8 g, 0.4 mol) was dissolved in water (200 mL) and added dropwise, while cooling the reaction mixture in an icebath reaching a maximal temperature of 27 °C. The reaction mixture was stirred for three hours at room temperature, followed by two hours at 50 °C and further 12 hours at room temperature. The biphasic mixture was extracted using methyl tert-butyl ether. The combined organic phase was washed with water, dried over anhydrous magnesium sulfate, filtered and concentrated. Compound 3b was obtained as a colorless solid (yield: 35.5%) after purification by vacuum distillation and recrystallization from methyl tert-butyl ether and cyclohexane.1H NMR (500 MHz, DMSO-d6): 5 0.87 (t, 3H), 1.10-1.40 (m, 12H), 3.25 (d, 6H), 4.20 (s, 3H) ppm.13C NMR (125 MHz, DMSO-d6): 5 13.9, 22.0, 22.3, 28.8, 29.1 , 30.2, 31.3, 43.3, 62.1 ppm. Example 3

[0183] Preparation of compound 1a (1 ,1 ,1 -trimethylolhexane triacrylate (TMHTA))

[0184] 51 .3 g compound 3a of example 1 , 22.8 g of cyclohexane, 68.7 g of acrylic acid, 0.096 g of a 31.5% solution of copper(ll) chloride in water, 0.47 g of H3PO2 and 0.035 g of methylhydroquinone were charged as a template and 75°C heated. At this temperature, 5.16 g of a 65% aqueous paratoluene sulfonic acid solution was added. The temperature was raised to 96 to 97 °C and maintained at this level by the addition of further cyclohexane. The progress of the reaction was determined by the amount of the reaction water formed. After about 10 hours the reaction was over. The work-up was carried out by aqueous extraction of the excess acrylic acid, removal of the solvent under reduced pressure and subsequent filtration of liquid compound 1a (1 ,1 ,1 -trimethylolhexane triacrylate (TMHTA)) over a Seitz K300 filter. The esterification yield was 84%.1H NMR (400 MHz, CDCL3): 5 0.88 (t, 3H), 1.16-1.22 (m, 8H), 4.01 (s, 6H), 5.83 (d, 3H), 6.12 (m, 3H), 6.41 (d, 3H) ppm. EI-MS m / z: [M + H]+calc for Ci8H26O6, 338.17; found, 338.17.

[0185] Comparative example 1 Preparation of ethoxylated 1 ,1 ,1 -trimethylolpropane triacrylate (TMPEOTA)

[0186] 679 g of ethoxylated 1 ,1 ,1 -trimethylolpropane (average ethoxylation degree of 3.5), 108 g of cyclohexane, 521 g of acrylic acid, 0.96 g of a 31.5% solution of copper(ll) chloride in water, 3.58 g of H3 O2 and 0.27 g of methylhydroquinone were charged as a template and 75 °C heated. At this temperature, the catalyst (39.69 g of a 65% aqueous paratoluene sulfonic acid solution) was added. The temperature was raised to 96 to 97°C and maintained at this level by the addition of further cyclohexane. The progress of the reaction was determined by the amount of the reaction water formed. After about 10 hours the reaction was over. The work-up was carried out by aqueous extraction of the excess acrylic acid, removal of the solvent under reduced pressure and subsequent filtration of liquid TMPEOTA over a Seitz K300 filter. The esterification yield was 92%. Comparative example 2

[0187] Preparation of 1 ,1 ,1 -trimethylolpropane triacrylate (TMPTA)

[0188] (TMPTA)

[0189] 43,3 g 1,1 ,1 -trimethylolpropane, 10.8 g of cyclohexane, 76.7 g of acrylic acid, 0.096 g of a 31.5% solution of copper(ll) chloride in water, 0.47 g of H3PO2 and 0.035 g of methylhydroquinone were charged as a template and 75°C heated. At this temperature, the catalyst (5.16 g of a 65% aqueous paratoluene sulfonic acid solution) was added. The temperature was raised to 96 to 97°C and maintained at this level by the addition of further cyclohexane. The progress of the reaction was determined by the amount of the reaction water formed. After about 10 hours the reaction was over. The work-up was carried out by aqueous extraction of the excess acrylic acid, removal of the solvent under reduced pressure and subsequent filtration of liquid TMPTA over a Seitz K300 filter. The esterification yield was 87%.

[0190] Comparative example 3

[0191] Preparation of 1 ,1 ,1 -trimethylolethane triacrylate (TMETA)

[0192] (TMETA)

[0193] 40,3 g 1,1 ,1 -trimethylolethane, 10.8 g of cyclohexane, 79.7 g of acrylic acid, 0.096 g of a 31.5% solution of copper(ll) chloride in water, 0.47 g of H3PO2 and 0.035 g of methylhydroquinone were charged as a template and 75°C heated. At this temperature, the catalyst (5.16 g of a 65% aqueous paratoluene sulfonic acid solution) was added. The temperature was raised to 96 to 97°C and maintained at this level by the addition of further cyclohexane. The progress of the reaction was determined by the amount of the reaction water formed. After about 10 hours the reaction was over. The work-up was carried out by aqueous extraction of the excess acrylic acid, removal of the solvent under reduced pressure and subsequent filtration of liquid TMETA over a Seitz K300 filter. The esterification yield was 86%.

[0194] Example 4

[0195] Preparation of oligomer 2a (BADGEDA)

[0196] 859.12 g Epikote 828 (epoxy resin from bisphenol A and epichlorohydrin, epoxy group content: 5260 to 5420 mmol / kg, viscosity at 25 °C: 12 to 14 Pa*s at 25 °C, Epikote 828 does not contain any diluent) (7a), 1.2 g Kerobit TBK (2,6-di-tert-butyl-4-methylphenol), 0.6 g 4-methoxyphenol and 0.12 g phenothiazine were placed in a 2 L four neck round-bottom flask with a stirrer, a thermometer, a condenser, and a dropping funnel. The mixture was stirred and heated to 100 °C. Afterwards, 6.0 g tetraethylammonium bromide dissolved in 34.09 g of acrylic acid were added, before 306.79 g of acrylic acid was added dropwise via the dropping funnel to the mixture at 103-107 °C. After the completion of acrylic acid addition, the reaction was kept at 103 to 107 °C for 35 minutes. The acid value of the mixture in the flask was determined at definite time intervals, and the reaction was stopped when the acid value was lower than 5 mg KOH / g. Oligomer 2a (BADGEDA) was obtained as slightly yellow viscous liquid. The final acid value was 2.2 mg KOH / g, and its viscosity was -250 Pa*s at 23 °C.

[0197] Example 5

[0198] Preparation of coating compositions comprising compound 1a (TMHTA), TMPEOTA, TMPTA and TMETA, respectively, and 2a (BADGEDA)

[0199] Compound 1a (TMHTA) of example 3, was mixed with Irgacure 184 (photoinitiator) to yield a coating composition (0 wt% 2a (BADGEDA)). The concentration of Irgacure 184 was 4% by weight based on the weight of the coating composition.

[0200] Compound 1a (TMHTA) of example 3 was mixed with 2a (BADGEDA) of example 4. The weight ratio of 2a (BADGEDA) of example 4 to the mixture of 2a (BADGEDA) of example 4 and compound 1a (TMHTA) of example 3 was 10% (10 wt% BADGEDA content), 20% (20 wt% BADGEDA content), 30% (30 wt% BADGEDA content), 40% (40 wt% BADGEDA content) and 50% (50 wt% BADGEDA content), respectively. Irgacure 184 (photoinitiator) was added at a concentration of 4 weight% based on the weight of the coating composition. In analogy TMPEOTA of comparative example 1 , TMPTA of comparative example 2 and TME- TA of comparative example 3, respectively, was mixed with Irgacure 184 (photoinitiator) to yield a coating composition (0 wt% BADGEDA content). The concentration of Irgacure 184 was 4% by weight based on the weight of the coating composition.

[0201] In analogy TMPEOTA of comparative example 1 , TMPTA of comparative example 2 and TME- TA of comparative example 3, respectively, was mixed with oligomer 2a (BADGEDA) of example 4. The weight ratio of oligomer 2a (BADGEDA) of example 4 to the mixture of oligomer 2a (BADGEDA) of example 4 and TMPEOTA of comparative example 1 , TMPTA of comparative example 2 and TMETA of comparative example 3, respectively, was 10% (10 wt% BADGEDA content), 20% (20 wt% BADGEDA content), 30% (30 wt% BADGEDA content), 40% (40 wt% BADGEDA content) and 50% (50 wt% BADGEDA content), respectively. Irgacure 184 (photoinitiator) was added at a concentration of 4 weight% based on the weight of the coating composition.

[0202] The viscosity of the coating compositions was determined after storage in a climate chamber for at least 24 hours. The viscosity was measured with a Brookfield viscometer at 23 °C, speed gradient of 1000 s’1, according to DIN EN ISO 3219-2:2021.

[0203] The results are shown in Figure 1 .

[0204] Figure 1 shows that the viscosity decreases with increasing content of reactive diluent.

[0205] The coating compositions were applied to glass plates using a box doctor blade, the nip width of the doctor blade being 120 pm (this implies that the wet film thickness of the applied coating was 120 pm). The wet layers were cured immediately afterwards with UV for two times at a belt speed of 5 m / min under ambient conditions. For curing, an 1ST UV system was used (type: M- 40-2xl-R-TR-SLC-SO-lnert, lamp 1 : 1ST UV lamp M400 U2HC, lamp 2: 1ST UV lamp M400 U2H). The Martens hardness was determined after storage in a climate chamber for at least 24 hours. The Martens hardness was determined via micro indentation with a FISCHERSCOPE HM2000 S. The device measured and calculated the Martens hardness according to DIN EN ISO 14577-1 :2015 Annex A and ASTM E 2546.

[0206] The results are shown in Figure 2.

[0207] Figure 2 shows that the coating compoition comprising compound 1a (TMHTA) and 0 wt% BADGEDA has almost the same Martens hardness than coating compositions comprising compound 1a (TMHTA) and 10, 20, 30, 40 and 50 wt% BADGEDA, respectively.

[0208] Therefore, the Martens hardness of coating compositions comprising compound 1a (TMHTA) and 0, 10, 20, 30, 40 and 50 wt% BADGEDA are about the same.

[0209] Figure 2 also shows that, in contrast, coating compositions comprising TMPEOTA of comparative example 1 , and 0, 10, 20, 30, 40 and 50 wt% BADGEDA, respectively, have different Mar- tens hardnesses. The same applies to coating compositions comprising TMPTA of comparative example 2 and TMETA of comparative example 3, respectively, and 0, 10, 20, 30, 40 and 50 wt% BADGEDA.

Claims

Claims1 . A compound of formulawhereinR1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, whereinC4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-8-cycloalkyl, C5-8- cycloalkenyl or C4-8-heterocycloalkyl, andCe-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-8-cycloalkyl or C4-8- heterocycloalkyl,R2is H or methyl and n is 1.0 to 6.0.

2. The compund of claim 1 , wherein R1is Cs-8-alkyl, Cs-8-alkenyl or Cs-s-alkinyl , and R2is H or methyl.

3. The compound of claim 1 , wherein R1is pentyl and R2is H.

4. The compound of any of claims 1 to 3, wherein n is 1 .0 to 4.0.

5. The compound of any of claims 1 to 3, wherein n is 1 .0 to 2.0.

6. A composition comprising at least one compound of any of claims 1 to 5, at least one oligomer or polymer (P) different from compound (1), which oligomer or polymer (P) is curable by radical polymerization, and optionally at least one radical initiator (I).

7. The composition of claim 6, wherein the oligomer or polymer (P) carries at least one group of formulawherein R3is H or methyl.

8. The composition of claim 7, wherein the oligomer or polymer (P) carries at least one group of formula(11")(11*) wherein R3is H or methyl.

9. The composition of claim 8, wherein the oligomer or polymer (P) is at least one oligomer or polymer selected from the group consisting ofwherein L1is an organic residue,R3is H or methyl, and m is 0 to 16.0.

10. The composition of claim 9, wherein L1isR3is H or methyl, and m is 0.1 to 16.0.11 . The composition of any of claims 6 to 10, wherein the composition comprises 10.0 to 98.0% by weight of the compound of formula (1 ) and2.0 to 90.0% by weight of oligomer or polymer (P) based on the weight of the composition.

12. The composition of any of claims 6 to 11 , wherein the composition comprises0.1 to 15.0% by weight of radical initiator (I) based on the weight of the compound of formula (1) and of the oligomer or polymer (P).

13. A cured layer formed from the composition of any of claims 6 to 12 on a substrate.

14. A substrate comprising the cured layer of claim 13.

15. A process for the preparation of the compound of formulawhereinR1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, whereinC4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-s- cycloalkenyl or C4-8-heterocycloalkyl, andCe-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl,R2is H or methyl. and n is 1.0 to 6.0, which process comprises the step of reacting a compound of formulawhereinR1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, whereinC4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, C5-8- cycloalkenyl or C4-8-heterocycloalkyl, andCe-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, and n is 1.0 to 6.0, with a compound of formulawherein R2is H or methyl.

16. A process for the preparation of a compound of formulawherein R1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, wherein C4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, C5-8- cycloalkenyl or C4-s-heterocycloalkyl, and Cs-14-aryl, Cs-12-heteroaryl, Cs-12-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, which process comprises the steps of(i) reacting a compound of formulaCX <5> whereinR1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Cs-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, whereinC4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, C5-8- cycloalkenyl or C4-8-heterocycloalkyl, andCe-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci-10-alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, with formaldehyde to obtain a compound of formulawhereinR1is C4-9-alkyl, C4-9-alkenyl, C4-9-alkinyl, Ce-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, C5-12- cycloalkenyl or C4-i2-heterocycloalkyl, whereinC4-9-alkyl can be substituted with phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl, Cs-8- cycloalkenyl or C4-8-heterocycloalkyl, andCe-14-aryl, C3-i2-heteroaryl, C3-i2-cycloalkyl, Cs-12-cycloalkenyl and C4-i2-heterocycloalkyl can be substituted with Ci- -alkyl, phenyl, Cs-s-heteroaryl, Cs-s-cycloalkyl or C4-8- heterocycloalkyl, and(ii) reducing the compound of formula (6) with hydrogen to obtain the compound of formula (3”).

17. The use of the composition of any of claims 6 to 12 as paint or varnish composition.

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