Photoinitiators

Abstract

The present invention relates to novel photoinitiators having improved performance, their use in photopolymerization compositions, and to methods of photopolymerization of compositions comprising said photoinitiators, as well as their use in industrial products, including printed products, coated products, and fabricated products.

Description

[Technical field]

[0001] The present invention relates to novel photoinitiators having improved performance, their use in photopolymerization compositions, and to methods of photopolymerization of compositions comprising said photoinitiators, as well as their use in industrial products, including printed products, coated products, and fabricated products. [Background technology]

[0002] In recent years, the design and development of new photoinitiators (PIs) has attracted attention due to the extensive use of photoinitiators that have been or are scheduled to be banned as toxic or reproductive toxins.

[0003] Various attempts have been made to mimic standard photoinitiators or provide new photoinitiators that can overcome challenges such as yellowing, fast line speeds, curing under LED lamps, etc.

[0004] Unfortunately, when used in standard applications, these photoinitiators also exhibit several limitations, such as poor surface curability and, most importantly, post-cure yellowing, which make the PIs unsuitable for use in polymerizable systems, including clear varnishes.

[0005] WO2015 / 010729 discloses certain polyols having 4-phenylbenzophenone residues, which are said to offer one or more advantages, including reduced mobility or odor and increased reactivity.

[0006] Unfortunately, these photoinitiators still exhibit high post-cure yellowing and reactivity under LED lamps. There is therefore a constant demand for new technical solutions which make it possible to limit yellowing after curing while at the same time providing good reactivity in the polymerization. Summary of the Invention [Problem to be solved by the invention]

[0007] It is a first object of the present invention to provide novel photoinitiators (PIs), their use as photoinitiators and photocurable compositions comprising them.

[0008] It is another object of the present invention to provide photocurable compositions comprising the novel PIs of the present invention.

[0009] It is yet another object of the present invention to provide a method for photocuring ethylenically unsaturated compounds using the novel PIs of the present invention, as well as industrial products produced thereby. [Means for solving the problem]

[0010] It has been surprisingly discovered that certain photoinitiators not only react well with the UVA, UVB and UVC wavelength ranges, but also more preferably with LED sources emitting in the 350-420 nm wavelength range, while maintaining low post-cure yellowing (representing a technological advance over the prior art).

[0011] In fact, it is known that good performance under LED lamps is always paired with high post-cure yellowing, which is highly undesirable. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] According to one aspect, the present invention relates to compounds of formula (I): Formula (I) [ka] [where: G is an optionally ethoxylated and / or propoxylated monomeric, oligomeric, or polymeric polyol G-(OH) n+p is a residue of; n is 1 to 8; p is 0 to 7; n+p is 2 to 8; and Z is represented by the following formulae (i), (ii) and (iii): [ka] (where: X, Y and W are each independently selected from O, S and C(R2)(R3); R1 is selected from hydrogen, halogen, substituted or unsubstituted C1-C20 alkyl, C5-C7 cycloalkyl, C3-C12 alkenyl, -O(C3-C12 alkenyl), -S(C3-C12 alkenyl), aryl, substituted or unsubstituted C1-C20 alkoxy, C1-C50 alkyl interrupted by one or more oxygens, C5-C7 cycloalkoxy, aryloxy, substituted or unsubstituted C1-C20 alkylthio, arylthio, substituted or unsubstituted (C1-C12 alkyl)2 amino, (C5-C7 cycloalkyl)2 amino, morpholino, piperidino, piperazino, and N(C1-C12 alkyl)piperazino; R2 and R3 are each independently selected from H, C1-C12 alkyl, OH, and C1-C10 alkoxy; and The wavy line represents the bond connected to the keto group in formula (I). Selected from.

[0013] According to another embodiment, X, Y and W are selected from O, S, C(R2)(R3), and N(R4), where R4 is selected from hydrogen, substituted or unsubstituted aryl, and C1-C8 alkyl.

[0014] According to the present invention, G-(OH) n+p is selected from monomeric, oligomeric, polymeric polyols or mixtures thereof, optionally ethoxylated and / or propoxylated.

[0015] Examples of suitable monomeric and oligomeric polyols are ethylene glycol, propylene glycol, 1,2-butanediol, 1,2-propanediol, 1,2-hexanediol, diethanolamine, N-methyldiethanolamine, glycerol, di-glycerol, tri-glycerol, triethanolamine, trimethylolpropane, di-trimethylolpropane, pentaerythritol, di-pentaerythritol, sugar alcohols (e.g., sorbitol, mannitol, xylitol), and mixtures thereof.

[0016] Examples of polymeric polyols are alkoxylated compounds, polyhydroxy polyethers (aliphatic or aromatic), polyhydroxy polyesters, polyhydroxy polyamides, polyhydroxy polyimides, polyhydroxy polycarbonates, and styrene-allyl alcohol.

[0017] Alkoxylated polyols are particularly preferred for the realization of the present invention. Examples of such alkoxylated polyols are the monomeric and oligomeric polyols mentioned above, which are alkoxylated, for example ethoxylated and / or propoxylated and / or butoxylated.

[0018] Other suitable examples are linear or branched polyamines, alkoxylated and polyalkoxylated diamines, such as ethoxylated ethylene diamines and ethoxylated 1,3-propylene diamines.

[0019] In the alkoxylated compounds of the present invention, each group reactive towards alkylene oxide can have 0 to 15 alkoxy units, preferably 1 to 6 alkoxy units.

[0020] In a preferred embodiment, G-(OH) n+p is selected from monomeric and oligomeric polyols.

[0021] In other preferred embodiments, G-(OH) n+pis selected from ethoxylated and / or propoxylated monomeric and oligomeric polyols.

[0022] Preferably, G-(OH) n+p has a number average molecular weight of 1,500 Da or less, more preferably 1,000 Da or less, and most preferably 800 Da or less.

[0023] Preferably, G-(OH) n+p is selected from glycerol, ethoxylated and / or propoxylated glycerol, ethoxylated and / or propoxylated di-glycerol, trimethylolpropane, ethoxylated and / or propoxylated trimethylolpropane, di-trimethylolpropane, ethoxylated and / or propoxylated di-trimethylolpropane, pentaerythritol, ethoxylated and / or propoxylated pentaerythritol, di-pentaerythritol, ethoxylated and / or propoxylated di-pentaerythritol, sorbitol, ethoxylated and / or propoxylated sorbitol, triethanolamine, and ethoxylated and / or propoxylated triethanolamine.

[0024] G-(OH) n+p Here is an example: [ka] (currently commercially available from PERSTORP under the trade name Polyhol 3380); [ka] (Currently commercially available from Lamberti SpA under the trade name AIONICO GL / 609, or from Clariant under the trade name Polyglycol G 500) (wherein "a", "b", and "c" each independently represent the number of ethoxy units from 0 to 15, preferably 1 to 6; and the PEG has a weight average molecular weight of about 200 kDa.)

[0025] Preferably, n+p is 2-8, and more preferably 3-6.

[0026] Preferably, n is 1-6, more preferably 2-6, further preferably 3-6, and most preferably 3-5.

[0027] Preferably, p is 0-6, more preferably 0-3.

[0028] It will be apparent that when p is not 0, the compound of formula (I) contains a free alcohol group.

[0029] Preferably, R1 is hydrogen, halogen, C1-C20 alkyl, C1-C20 alkoxy, C1-C20 thioalkyl, substituted or unsubstituted (C1-C12 alkyl)2 amino, morpholino, piperidino, piperazino, and N(C1-C12 alkyl)piperazino; more preferably, R1 is hydrogen or C1-C20 alkyl, most preferably hydrogen.

[0030] Preferably, R2 and R3 are both hydrogen.

[0031] According to a preferred embodiment, Z is (i).

[0032] According to a preferred embodiment, X is S, O, preferably S.

[0033] According to a preferred embodiment, Z is (i) and X is S, O, preferably S.

[0034] According to a preferred embodiment, Z is (iii).

[0035] According to a preferred embodiment, W is C(R2)(R3).

[0036] According to a preferred embodiment, Z is (iii) and W is C(R2)(R3).

[0037] According to a preferred embodiment, Z is (iii), W is C(R2)(R3), and R2 and R3 are both hydrogen.

[0038] When X, Y or W is S, sulfur may also be present in the form oxidized to sulfone or sulfoxide and is included in the scope of protection of the present invention.

[0039] As used herein, the term "alkyl" or "alkyl group", unless otherwise indicated, means a straight or branched saturated alkyl chain containing the specified number of carbon atoms and includes all possible isomers for each number of carbon atoms in each alkyl group, i.e., for 3 carbon atoms, n-propyl and isopropyl; for 4 carbon atoms, n-butyl, isobutyl, and tert-butyl; for 5 carbon atoms, n-pentyl, 1,1-dimethyl-propyl, 2,2-dimethylpropyl, and 2-methyl-butyl, etc.

[0040] "Alkenyl" or "alkenyl group" means an unsaturated group containing 2 to 12 carbon atoms, preferably C3 to C12 carbon atoms, for example, allyl, methallyl, or undecenyl.

[0041] The term "cycloalkyl" or "cycloalkyl group", unless otherwise indicated, preferably refers to an aliphatic ring containing 5 or 6 carbon atoms, e.g., cyclopentyl or cyclohexyl.

[0042] The term "aryl" or "aryl group" includes substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, anthracenyl, indenyl, and fluorenyl groups, preferably, but not limited to, substituted or unsubstituted phenyl or substituted or unsubstituted naphthyl groups.

[0043] The expression "C1-C50 alkyl interrupted by one or more oxygens" means that if more than one oxygen atom is present, said oxygen atoms are separated from each other by at least one methylene group, i.e. the oxygen atoms are non-consecutive. Preferably the oxygen atoms are separated by an ethylene or n-propylene chain. Preferably there are 1 to 20 oxygen atoms, more preferably 2 to 18. Examples include -O-CH2-OCH3, -O-CH2CH2-OCH2CH3, -O-[CH2CH2O] v CH3, -O-[CH2CH2O] v OH, -O-[CH2CH2O] v CH2CH3, -CH2-O-[CH2CH2O] v CH3 (where v=1-24), -O-[CH2CH2CH2O] p OH, -O-[CH2CH2CH2O] p CH3, -O-[CH2CH2CH2O] p CH2CH 3、 -CH2-O-[CH2CH2CH2O] p CH3 (where p=1-16), but are not limited to these.

[0044] When a group is defined as substituted, unless otherwise limited, the term "substituted" means that said group has one or more substituents, preferably selected from halogen atoms, alkyl, aryl, cycloalkyl, alkoxy, aryloxy, alkylamino, dialkylamino, alkylthio or arylthio groups, heterocyclic groups, and phosphorus or silicon containing groups. More preferably, the term "substituted" as used herein refers to one or more groups selected from methyl, ethyl, isopropyl, tert-butyl, phenyl, trifluoromethyl, cyano, acetyl, ethoxycarbonyl, carboxyl, carboxylate, amino, methylamino, dimethylamino, ethylamino, diethylamino, isopropylamino, diisopropylamino, cyclohexylamino, dicyclohexylamino, acetylamino, piperidino, pyrrolidyl, methoxy, ethoxy, propoxy, isopropoxy, butoxy, pentyloxy, phenoxy, hydroxyl, acetoxy, -POH, methylthio, ethylthio, i-propylthio, n-propylthio, phenylthio, mercapto, acetylthio, thiocyano, methylsulfinyl, methylsulfonyl, dimethylsulfonyl, sulfonate groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, trimethylsilyl, pentamethyldisilyl, triethylsilyl, trimethylstannyl, furyl, thienyl, pyridyl, and morpholino. Among the above-mentioned substituents, alkoxy groups (e.g., methoxy, ethoxy, isopropoxy, tert-butoxy, or phenoxy), methyl, ethyl, isopropyl, hydroxyl, acetoxy, benzoyloxy groups, etc., thioalkyl groups (e.g., methylthio, ethylthio, n-propylthio, i-propylthio, butylthio, phenylthio), or arylthio groups (e.g., phenylthio) are preferred.

[0045] The compounds of the present invention can be prepared according to any suitable method, for example by reacting a compound ZH (where Z is as defined above) with phthalic anhydride in a suitable organic solvent in the presence of a Lewis catalyst to produce a compound of formula (II); and then reacting said compound (II) with a desired polyol in a suitable organic solvent in the presence of p-toluenesulfonic acid to produce a compound of formula (I).

[0046] Suitable organic solvents for the preparation of compounds of formula (II) are, for example, haloaromatic solvents such as chlorobenzene.

[0047] Suitable organic solvents for the preparation of compounds of formula (I) are, for example, aromatic solvents such as toluene, xylene, and the like.

[0048] The above chemical reactions are perfectly capable of being carried out by one skilled in the art.

[0049] Details of the method of the invention are in any case reported in the "Experimental Part" of this specification.

[0050] Particularly preferred PIs according to the present invention are: TIFF2025507677000005.tif219156 TIFF2025507677000006.tif219156 TIFF2025507677000007.tif203156 TIFF2025507677000008.tif230156 The letters "a" to "f" represent the number of ethoxy units, each independently being 0 to 15, more preferably 1 to 6.

[0051] Of the above compounds, those in which Z is (i) and X is S; and those in which Z is (iii) and X is CH2 are preferred.

[0052] According to another aspect, the present invention provides a method for producing a method for manufacturing a semiconductor device comprising: a) 50 to 99.9% by weight, preferably 70 to 98.9% by weight (based on the total weight of the composition) of at least one ethylenically unsaturated compound; b) 0.1 to 35% by weight, preferably 0.1 to 20% by weight, more preferably 0.2 to 15% by weight (based on the total weight of the composition) of at least one compound of formula (I) as defined above; and c) Accelerators and / or coinitiators: 0 to 20% by weight, preferably 0 to 15% by weight, more preferably 0.2 to 15% by weight (based on the total weight of the composition) The present invention relates to a photopolymerizable composition comprising:

[0053] In accordance with the present invention, the terms "photohardenable" and "photopolymerizable" and related terms are synonymous.

[0054] The expression "based on the total content of the composition" means that the amount (% by weight) of each component is calculated relative to the total weight of all components of the composition (including components a), b), and c) above as well as further additional components), but water and / or solvents that may be present in the composition are not taken into account in calculating said amounts (% by weight).

[0055] According to another aspect, the present invention relates to a method for photocuring photopolymerizable compositions, coatings, adhesives and inks, the method comprising: i. providing a photopolymerizable composition as defined above; ii. coating or printing the photopolymerizable composition onto a substrate; and iii. photocuring the coated or printed composition on the substrate with a light source. The present invention relates to a method for producing a semiconductor device comprising the steps of:

[0056] According to another aspect, the present invention relates to a three-dimensional printing method comprising photocuring a mixture comprising the photopolymerizable composition defined above with a light source.

[0057] According to another aspect, the present invention relates to a product obtained by the method of the present invention.

[0058] According to a preferred embodiment, the photopolymerizable composition used in the method of the present invention comprises at least components a), b) and c), more preferably at least components a), b), c) and d) as defined above.

[0059] Compared with the PIs of the prior art, in particular those disclosed in WO2015 / 010729, the PIs of the present invention exhibited significantly lower yellowing (measured as yellowing index), as demonstrated in the "Experimental Section" below.

[0060] The photoinitiators of the present invention are used in photocurable compositions comprising ethylenically unsaturated compounds a) which can contain one or more olefinic double bonds. They are low molecular weight (monomeric) or high molecular weight (oligomeric) compounds.

[0061] Examples of suitable low molecular weight monomers (monomeric compounds) with one double bond are alkyl or hydroxyalkyl acrylates or methacrylates, such as methyl-, ethyl-, butyl-, 2-ethylhexyl-, 2-hydroxyethyl-, or isobornyl-acrylate; and methyl or ethyl methacrylate. Further examples are silicon- or fluorine-modified resins, such as silicone acrylates. Further examples of these monomers are acrylonitrile, acrylamide, methacrylamide, N-substituted (meth)acrylamides, styrene, alkylstyrenes, and halogenostyrenes, vinyl esters, such as vinyl acetate, vinyl ethers, such as iso-butyl vinyl ether, N-vinylpyrrolidone, vinyl chloride, or vinylidene chloride.

[0062] Examples of monomers having two or more double bonds are ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, hexamethylene glycol diacrylate, bisphenol A diacrylate, 4,4'-bis-(2-acryloyloxyethoxy)-diphenylpropane, trimethylolpropane triacrylate, pentaerythritol triacrylate or tetraacrylate, vinyl acrylate, divinylbenzene, divinyl succinate, diallyl phthalate, triallyl phosphate, triallyl isocyanurate, or tris-(2-acryloylethyl)isocyanurate.

[0063] Examples of polyunsaturated compounds of high molecular weight (oligomeric) are acrylated epoxy resins, acrylated or vinyl-ether- or epoxy-group-containing polyesters, acrylated polyurethanes, or acrylated polyethers. Further examples of unsaturated oligomers are unsaturated polyester resins, usually prepared from maleic acid, phthalic acid and one or more diols, and having a molecular weight of about 500 to 3000 Da. Such unsaturated oligomers are also called prepolymers.

[0064] Examples of compounds a) which are particularly suitable for carrying out the invention are esters of ethylenically unsaturated carboxylic acids and of polyols or polyepoxides, and polymers which contain ethylenically unsaturated groups in the main chain or in the side chain, such as unsaturated polyesters, polyamides and polyurethanes, and copolymers thereof, alkyl resins, polybutadienes and butadiene copolymers, polyisoprene and isoprene copolymers, polymers and copolymers which have (meth)acrylic groups in the side chain, and mixtures thereof.

[0065] Illustrative of unsaturated carboxylic acids and anhydrides useful in preparing such esters are acrylic acid, methacrylic acid, maleic anhydride, crotonic acid, itaconic acid, cinnamic acid, and unsaturated fatty acids such as linoleic acid, and oleic acid. Acrylic acid and methacrylic acid are preferred.

[0066] Examples of polyols to be esterified are aromatic and aliphatic and cycloaliphatic polyols, preferably aliphatic and cycloaliphatic polyols.

[0067] Aromatic polyols are, for example, hydroquinone, 4,4'-dihydroxyphenyl, 2,2-di(4-hydroxyphenyl)propane, as well as novolaks and resols. The polyepoxides to be esterified are based on the abovementioned polyols and include, in particular, the reaction products between aromatic polyols and epichlorohydrin. Polymers and copolymers containing hydroxyl groups in the polymer chain or in the side chains, such as polyvinyl alcohol and its copolymers or polymethacrylic acid hydroxyalkyl esters or its copolymers, are also suitable as polyols. Further suitable polyols are oligoesters with hydroxy end groups.

[0068] Examples of aliphatic and cycloaliphatic polyols include alkylene diols preferably containing 2 to 12 carbon atoms, such as ethylene glycol, 1,2- or 1,3-propanediol, 1,2-, 1,3- or 1,4-butanediol, pentanediol, hexanediol, octanediol, dodecanediol, diethylene glycol, triethylene glycol, polyethylene glycols preferably having a molecular weight of 200 to 1500 Da, 1,3-cyclopentanediol, 1,2-, 1,3- or 1,4-cyclohexanediol, 1,4-dihydroxymethylcyclohexane, glycerol, tris(β-hydroxyethyl)amine, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, and sorbitol.

[0069] Further suitable ethylenically unsaturated compounds a) are unsaturated polyamides obtained from unsaturated carboxylic acids and aromatic, aliphatic and cycloaliphatic polyamines, preferably having 2 to 6, preferably 2 to 4, amino groups. Examples of such polyamines are ethylenediamine, 1,2- or 1,3-propylenediamine, 1,2-, 1,3- or 1,4-butylenediamine, 1,5-pentylenediamine, 1,6-hexylenediamine, octylenediamine, dodecylenediamine, 1,4-diaminocyclohexane, isophoronediamine, phenylenediamine, bisphenylenediamine, di-(β-aminoethyl)ether, diethylenetriamine, triethylenetetraamine and di(β-aminoethoxy)- and di(β-aminopropoxy)ethane. Other suitable polyamines are polymers and copolymers containing additional amino groups in the side chain and oligoamides containing amino end groups.

[0070] Examples of such unsaturated polyamides are methylenebisacrylamide, 1,6-hexamethylenebisacrylamide, diethylenetriaminetrismethacrylamide, bis(methacrylamidopropoxy)ethane, and N-[(β-hydroxyethoxy)ethyl]-acrylamide.

[0071] Unsaturated polyurethanes are also suitable as component a) for the implementation of the present invention, for example those derived from saturated or unsaturated diisocyanates and unsaturated or saturated diols. Polybutadienes and polyisoprenes and their copolymers can also be used.

[0072] Suitable monomers include, for example, olefins such as ethylene, propene, butene and hexene, (meth)acrylates, acrylonitrile, styrene, and vinyl chloride.

[0073] Polymers having unsaturated (meth)acrylate groups in the side chain are also used as component a). They are typically reaction products of novolac epoxy resins with (meth)acrylic acid, homo- or copolymers of vinyl alcohol or its hydroxyalkyl derivatives esterified with (meth)acrylic acid, and homo- and copolymers of (meth)acrylates esterified with hydroxyalkyl (meth)acrylates.

[0074] According to a preferred embodiment, the photocurable composition further comprises a coinitiator c), also called accelerator.

[0075] Suitable examples of accelerators / co-initiators c) are alcohols, thiols, thioethers, amines or ethers with an available hydrogen attached to the carbon adjacent to a heteroatom, disulfides and phosphines (for example as described in EP 438123 and GB 2180358).

[0076] Suitable examples of amine accelerators / co-initiators include, but are not limited to, aliphatic, cycloaliphatic, aromatic, aryl-aliphatic, heterocyclic, oligomeric or polymeric amines, such as primary, secondary or tertiary amines, such as butylamine, dibutylamine, tributylamine, cyclohexylamine, benzyldimethylamine, di-cyclohexylamine, N-phenylglycine, triethylamine, phenyl-diethanolamine, triethanolamine, piperidine, piperazine, morpholine, pyridine, quinoline, esters of dimethylaminobenzoic acid, Michler's ketone (4,4'-bis-dimethylaminobenzophenone) and its derivatives.

[0077] Amine-modified acrylate compounds are used as amine accelerators / co-initiators, examples of such amine-modified acrylates include acrylates modified by reaction with primary or secondary amines (as described in US 3844916, EP 280222, US 5482649, or US 5734002).

[0078] Multifunctional amines and polymeric amine derivatives are also suitable as coinitiators, some examples being Omnipol® ASA (IGM Resins BV), Genopol® AB-2 (Rahn AG), Speedcure® 7040 (Lambson Limited), or those described in US 2013 / 0012611.

[0079] The photocurable composition of the present invention may also comprise, in addition to components a), b) and c) (if present), one or more of the following components: d) photosensitizers and / or e) further photoinitiators and / or f) conventional additives.

[0080] The photocurable compositions of the present invention may also be formulated as compositions further comprising water and / or a solvent, such as an organic solvent.

[0081] The photosensitizer d) can be present in an amount of 0.01 to 15% by weight, preferably 0.01 to 10% by weight, based on the total content of the composition.

[0082] Examples of photosensitizers are those commonly used in the art: aromatic carbonyl compounds, such as benzophenones, thioxanthones, anthraquinones, coumarins, and 3-acylcumarine derivatives, terphenyls, styryl ketones, and 3-(aroylmethylene)-thiazolines, camphorquinones, and eosin, rhodamine, erythrosine dyes.

[0083] Examples of thioxanthone include thioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-dodecylthioxanthone, 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, 1-methoxycarbonylthioxanthone, 2-ethoxycarbonylthioxanthone, 3-(2-methoxyethoxycarbonyl)thioxanthone, 4-butoxycarbonylthioxanthone, 3-butoxycarbonyl-7-methylthioxanthone, 1-cyano-3-chlorothioxanthone, Xanthone, 1-ethoxycarbonyl-3-chlorothioxanthone, 1-ethoxycarbonyl-3-ethoxythioxanthone, 1-ethoxycarbonyl-3-aminothioxanthone, 1-ethoxycarbonyl-3-phenylsulfurylthioxanthone, 3,4-di[2-(2-methoxyethoxy)ethoxycarbonyl]thioxanthone, 1-ethoxycarbonyl-3-(1-methyl-1-morpholinoethyl)thioxanthone, 2-methyl-6-dimethoxymethylthioxanthone, 2-methyl thioxanthone, 6-(1,1-dimethoxybenzyl)thioxanthone, 2-morpholinomethylthioxanthone, 2-methyl-6-morpholinomethylthioxanthone, N-allylthioxanthone-3,4-dicarboximide, N-octylthioxanthone-3,4-dicarboximide, N-(1,1,3,3-tetramethylbutyl)thioxanthone-3,4-dicarboximide, 1-phenoxythioxanthone, 6-ethoxycarbonyl-1-2-methoxythioxanthone, 6-ethoxy Carbonyl-2-methylthioxanthone, thioxanthone-2-polyethylene glycol ester, 2-hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthone-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, or those described in PCT / EP2011 / 069514, such as n-dodecyl-7-methyl-thioxanthone-3-carboxylate and N,N-diisobutyl-7-methyl-thioxanthone-3-carbamide. Polymeric thioxanthone derivatives, such as Omnipol® TX (IGM Resins BV), Genopol® TX-1 (Rahn AG), Speedcure® 7010 (Lambson Limited), are also suitable.

[0084] Examples of benzophenones are benzophenone, 4-phenylbenzophenone, 4-methoxybenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-dimethylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, 4-(4-methylthiophenyl)benzophenone, 3,3'-dimethyl-4-methoxybenzophenone, methyl 2-benzoylbenzoate, 4-(2-methylphenyl) ... hydroxyethylthio)benzophenone, 4-(4-tolylthio)benzophenone, 4-benzoyl-N,N,N-trimethylbenzenemethanaminium chloride, 2-hydroxy-3-(4-benzoylphenoxy)-N,N,N-trimethyl-1-propanaminium chloride monohydrate, 4-(13-acryloyl-1,4,7,10,13-pentaoxatridecyl)benzophenone, 4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyl)oxylethyl-benzenemethanaminium chloride, or those described in US 9938231 (e.g. Omnirad® 991 (IGM Resins BV)).

[0085] Polymeric benzophenone derivatives (such as those currently commercially available as Omnipol® BP, Omnipol® 2702 and Omnipol® 682 (all from IGM Resins BV), Genopol® BP-2 (from Rahn AG), and Speedcure® 7005 (from Lambson Limited)) are also suitable.

[0086] Examples of 3-acylcoumarin derivatives are 3-benzoylcoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-5,7-di(propoxy)coumarin, 3-benzoyl-6,8-dichlorocoumarin, 3-benzoyl-6-chlorocoumarin, 3,3'-carbonyl-bis[5,7-di(propoxy)coumarin], 3,3'-carbonyl-bis(7-methoxycoumarin), 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3-isobutyroylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-5,7-diethoxycoumarin, 3-benzoyl 5,7-dibutoxycoumarin, 3-benzoyl-5,7-di(methoxyethoxy)coumarin, 3-benzoyl-5,7-di(allyloxy)coumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoyl-7-diethylaminocoumarin, 3-isobutyroyl-1,7-dimethylaminocoumarin, 5,7-dimethoxy-3-(1-benzoyl)coumarin, 5,7-dimethoxy-3-(1-benzoyl)coumarin, 3-benzoylbenzo[f]coumarin, 7-diethylamino-3-thienoylcoumarin, 3-(4-cyanobenzoyl)-5,7-dimethoxycoumarin, or those described in EP 2909243 and WO 2017 / 216699.

[0087] Examples of 3-(aroylmethylene)thiazolidines are 3-methyl-1,2-benzoylmethylene-β-benzothiazoline, 3-methyl-2-benzoylmethylene-benzothiazoline, 3-ethyl-2-propionylmethylene-β-benzothiazoline.

[0088] Examples of other aromatic carbonyl compounds are acetophenone, 3-methoxyacetophenone, 4-phenylacetophenone, benzil (for example those described in WO 2013 / 164394), 2-acetylnaphthalene, 2-naphthaldehyde, 9,10-anthraquinone, 9-fluorenone, dibenzosuberone, xanthone, 2,5-bis(4-diethylaminobenzylidene)cyclopentanone, α-(p-dimethylaminobenzylidene), ketones such as 2-(4-dimethylamino-benzylidene)-indan-1-one or 3-(4-dimethylaminophenyl)-1-indan-5-yl-propenone, 3-phenylthiophthalimide, N-methyl-3,5-di(ethylthio)phthalimide.

[0089] Thioxanthones, coumarins, and 3-acylcumarines are particularly preferred.

[0090] It has been observed that the above component d) increases the activity of the photoinitiator b) without shortening the shelf life of the composition. Moreover, such a composition has the special advantage that the spectral sensitivity of the photoinitiator b) can be shifted to various desired wavelength regions by appropriately selecting the photosensitizer d). Those skilled in the art can select a suitable photosensitizer d) to make the photoinitiator b) function in various desired wavelength regions.

[0091] Possible further photoinitiators e) can be present in an amount of 0.5 to 15% by weight, preferably 1 to 10% by weight, of the composition, based on the total content of the composition.

[0092] Examples of suitable other photoinitiators e) are camphorquinone, benzophenone, benzophenone derivatives, acetophenone, acetophenone derivatives, dialkoxyacetophenones, α-hydroxyketones, α-aminoketones, 4-aroyl-1,3-dioxolanes, benzoin alkyl ethers and benzil ketals, for example benzil dimethyl ketal, ketosulfones, for example 1-[4-[(4-benzoyl-phenyl)-thio]-phenyl]-2-methyl-2-[(4-methyl-phenyl)-sulfonyl]-propan-1-one (Esacure® 1001 (IGM Resins BV)), 3-ketocoumarins, for example those described in EP 2909243 and WO 2017 / 216699, phenylglyoxylates and derivatives thereof, dimeric phenylglyoxylates, peresters, for example benzophenonetetracarboxylic acid peresters, for example EP 126541, acylphosphine photoinitiators (selected from mono-acylphosphine oxides, bis-acylphosphine oxides, tris-acylphosphine oxides, and polyfunctional mono- or bis-acylphosphine oxides), halomethyltriazines, hexaarylbisimidazole / co-initiator systems such as o-chlorohexaphenylbisimidazole in combination with 2-mercaptobenzothiazole, ferrocenium compounds or titanocenes such as dicyclopentadienyl-bis(2,6-difluoro-3-pyrrolo-phenyl)titanium, O-acyloxime ester photoinitiators.

[0093] Examples of α-hydroxyketones and α-aminoketones are 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, 2-hydroxy-1- {4-[4-(2-hydroxy-2-methyl-propionyl)-phenoxy]-phenyl}-2-methyl-propan-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, and 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone.

[0094] Examples of O-acyloxime ester photoinitiators are 1,2-octanedione, 1-[4-(phenylthio)phenyl]-2-(O-benzoyloxime), ethanone 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl] 1-(O-acetyloxime), or those described in GB 2339571.

[0095] Examples of acylphosphine photoinitiators include, but are not limited to, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-(2,4-dipentyloxyphenyl), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate, phenyl(2,4,6-trimethylbenzoyl)phosphinic acid, glycerol ethoxylated triester (Omnipol® TP (IGM Resins BV)).

[0096] Examples of halomethyltriazine photoinitiators are 2-[2-(4-methoxy-phenyl)-vinyl]-4,6-bis-trichloromethyl[1,3,5]triazine, 2-(4-methoxy-phenyl)-4,6-bis-trichloromethyl[1,3,5]triazine, 2-(3,4-dimethoxyphenyl)-4,6-bis-trichloromethyl[1,3,5]triazine, 2-methyl-4,6-bis-trichloromethyl[1,3,5]triazine.

[0097] If the photocurable composition according to the invention is used in a hybrid system (hybrid system in this respect means a mixture of a free radically curable system and a cationic curable system), cationic photoinitiators can also be used as further photoinitiators e). Examples of suitable cationic photoinitiators are aromatic sulfonium, phosphonium or iodonium salts, as described, for example, in US 4950581, or cyclopentadienylarenes-iron(II) complex salts, such as (η 6 -isopropylbenzene)(η 5 -cyclopentadienyl)iron(II) hexafluorophosphate or an oxime-based photolatent acid.

[0098] The photocurable composition according to the present invention may also contain common additives in an amount of 0-10% based on the total content of the composition. Additives f) are, for example, thermal initiators, binders, stabilizers, and mixtures thereof.

[0099] The choice of additives is determined based on the field of use and the properties desired for that field. The above additives f) are known in the art and are used in amounts commonly used in the art.

[0100] For example, especially in the case of colouring compositions, the composition may also comprise as further additive f) thermal initiators (compounds which form free radicals when heated), for example azo compounds such as 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), triazenes, diazosulfides, pentaazadienes, or peroxy compounds, for example hydroperoxides or peroxycarbonates (for example tert-butyl hydroperoxide), as described, for example, in EP 245639.

[0101] A binder may be added to the photocurable composition of the present invention. The addition of a binder is particularly advantageous when the photocurable compound is a liquid or viscous substance. The amount of binder is, for example, 5 to 60% by weight, preferably 10 to 50% by weight, based on the total content of the composition (excluding possible water and solvents). The selection of the binder is made according to the field of use and its required properties, such as developability in aqueous and organic solvent systems, adhesion to substrates, and sensitivity to oxygen.

[0102] A suitable binder is, for example, a polymer having a weight average molecular weight (Mw) of about 5,000 to 2,000,000 Da, preferably 10,000 to 1,000,000 Da. Illustrative examples are homopolymers and copolymers of acrylates and methacrylates, such as copolymers of methyl methacrylate / ethyl acrylate / methacrylic acid, poly(methacrylic acid alkyl esters), poly(acrylic acid alkyl esters); cellulose esters and ethers, such as cellulose acetate, cellulose acetate butyrate, methyl cellulose, ethyl cellulose, polyvinyl butyral, polyvinyl formal, cyclized rubbers, polyethers, such as polyethylene oxide, polypropylene oxide, polytetrahydrofuran, polystyrene, polycarbonate, polyurethanes, chlorinated polyolefins, such as polyvinyl chloride, vinyl chloride / vinylidene chloride copolymers, copolymers of vinylidene chloride with acrylonitrile, methyl methacrylate and vinyl acetate, polyvinyl acetate, co-poly(ethylene / vinyl acetate), polymers such as polycaprolactam and poly(hexamethylene adipamide), polyesters, such as poly(ethylene glycol terephthalate) and poly(hexamethylene glycol succinate).

[0103] Suitable stabilizers are, for example, thermal inhibitors, such as hydroquinone, hydroquinone derivatives, p-methoxyphenol, β-benzol, or sterically hindered phenols, such as 2,6-di(tert-butyl)-p-cresol, which prevent premature polymerization. To increase the dark storage stability, for example, copper compounds, such as copper naphthenate, copper stearate, or copper octenate, phosphorus compounds, such as triphenylphosphine, tributylphosphine, triethyl phosphite, triphenyl phosphite, or tribenzyl phosphite, quaternary ammonium compounds, such as tetramethylammonium chloride or trimethylbenzylammonium chloride, or hydroxylamine derivatives, such as N,N-diethylhydroxylamine, can be used. To remove oxygen from the atmosphere during polymerization, paraffin or similar wax-like substances can be used, which are insoluble in the polymer and migrate to the surface at the beginning of the polymerization, forming a transparent surface layer that prevents the ingress of air.

[0104] Light stabilizers such as UV absorbers, for example of the hydroxyphenylbenzotriazole, hydroxyphenylbenzophenone, oxalic acid amide or hydroxyphenyl-s-triazine type, can also be used. Such components can be used alone or in mixtures, with or without sterically hindered amines (HALS).

[0105] The photocurable compositions according to the invention can also contain as further additives f) photoreducible dyes, such as xanthene, benzoxanthene, benzothioxanthene, thiazine, pyronine, porphyrin or acridine dyes, and / or radiation-cleavable trihalomethyl compounds, which are described, for example, in EP 445624.

[0106] Further customary additives f) are, depending on the application, optical brighteners, fillers, pigments (both white and colored pigments), colorants, antistatic agents, wetting agents or flow improvers.Additives commonly used in the art, such as antistatic agents, flow improvers and adhesion promoters, can also be used.

[0107] In addition to the above ingredients, other ingredients may be present in compositions according to the present invention.

[0108] Chain transfer agents commonly used in the art can also be added to the compositions according to the invention. Examples are mercaptans, amines and benzothiazoles.

[0109] The compositions of the present invention may also comprise colorants and / or colored pigments. Depending on the application, both inorganic and organic pigments can be used. Such additives are known to those skilled in the art. Some examples are carbon black, iron oxides, such as yellow iron oxide, red iron oxide, chrome yellow, chrome green, nickel titanium yellow, ultramarine blue, cobalt blue, bismuth vanadate, cadmium yellow, and cadmium red. Examples of organic pigments are mono- or bis-azo pigments and their metal complexes, phthalocyanine pigments, polycyclic pigments, such as perylene, anthraquinone, thioindigo, quinacridone, or triphenylmethane pigments, and diketo-pyrrolo-pyrrole, isoindolinone, such as tetrachloroisoindolinone, isoindoline, dioxazine, benzimidazolone, and quinophthalone pigments. In the formulation, the pigments are used alone or as a mixture.

[0110] Depending on the application, pigments are added to the formulation in amounts commonly used in the art, for example, from 0.1 to 30% by weight, or from 10 to 25% by weight, based on the total weight of the composition.

[0111] The composition may, for example, contain a very wide variety of organic colorants. Examples are azo dyes, methine dyes, anthraquinone dyes and metal complex dyes. Usual concentrations are, for example, 0.1 to 20% by weight, in particular 1 to 5% by weight, based on the total weight of the composition.

[0112] The photocurable composition of the present invention may comprise water.

[0113] The photocurable compositions of the invention can be used for various purposes, for example as printing inks, e.g. screen printing inks, flexographic printing inks, offset printing inks and inkjet printing inks, as clearcoats, e.g. as pigmented coats for wood or metal, as powder coatings, in particular as coating materials for paper, wood, metal or plastics, as sunlight-curable paints for construction and road markings, for reprographic processes, for holographic recording materials, for image recording processes or for the production of printing plates using organic solvents or using an aqueous alkaline medium, for the production of screen printing masks, as dental filling materials, as adhesives, as pressure-sensitive adhesives, as laminating resins, as photoresists, e.g. galvano resists, as etch resists or permanent resists (both liquid and dry film), as photostructurable insulators and as solder masks for electronic circuits, in the production of color filters for various types of display screens or in the formation of structures during the production of plasma displays and electroluminescent displays, in the production of optical switches, optical gratings (interference gratings), by bulk curing (UV curing in transparent molds) or in stereolithography processes (e.g. US They are suitable for the production of three-dimensional articles by the process described in US Pat. No. 4,575,330 (Patent Publication No. 4,575,330), in the production of composite materials (e.g. styrene polyesters which may contain glass fibres and / or other fibres and other auxiliaries) or in three-dimensional printing processes well known to those skilled in the art, as resists in the coating or encapsulation of electronic components or as coatings for optical fibres.

[0114] The photocurable compositions of the present invention are also suitable for the manufacture of optical lenses, such as contact lenses or Fresnel lenses, for the manufacture of medical devices, aids or implants, and for dry film paints.

[0115] The photocurable compositions of the invention are also suitable for the preparation of gels having thermotropic properties, such gels being described, for example, in DE 19700064 and EP 678534.

[0116] Articles comprising the compounds of formula (I) according to the invention or comprising the photocurable compositions according to the invention are another subject of the present invention.

[0117] The compounds and compositions according to the invention are also used as free radical photoinitiators or photoinitiating systems for radiation curable powder coatings.

[0118] The photocurable compositions according to the invention are suitable, for example, as coating materials for all kinds of substrates, such as wood, textiles, paper, ceramics, glass, plastics (e.g. polyesters, polyethylene terephthalate, polyolefins, and cellulose acetate: especially in film form), and metals, such as Al, Cu, Ni, Fe, Zn, Mg, or Co, and also GaAs, Si or SiO2 (to which a protective layer is applied or to which an image is applied, for example by imagewise exposure).

[0119] In the method according to the invention, a wide variety of light sources can be used, the light sources emitting at wavelengths between about 200 and about 800 nm. Both point sources and flat radiators (lamp carpets) are suitable. Examples are carbon arc lamps, xenon arc lamps, medium, high and low pressure mercury arc radiators (doped with metal halides at suitable sites: metal halide lamps), microwave excited metal vapor lamps, excimer lamps, super actinic fluorescent tubes, fluorescent lamps, argon incandescent lamps, flash lamps, photographic floodlight lamps, light emitting diodes (LEDs), electron beams, X-rays and lasers.

[0120] According to one embodiment, the light source comprises ultraviolet light in at least one of the UVA, UVB, and UVC ranges.

[0121] According to a preferred embodiment, said light source is an LED source, in particular LED light sources emitting at wavelengths between 365 and 420 nm, more preferably 365 nm, 385 nm and 395 nm, are particularly preferred.

[0122] According to the invention, the distance between the lamp and the substrate to be exposed can vary depending on the application and the type and strength of the lamp, and is, for example, from 0.1 to 150 cm, preferably from 1 to 50 cm.

[0123] The photopolymerizable composition may also be applied onto a substrate that already comprises a coated or printed layer. After the photopolymerizable composition has been photopolymerized with the light source, it may be overprinted or overcoated with one or more compositions suitable for printing or coating.

[0124] The article obtained by applying said photopolymerizable composition onto said substrate by said coating or printing means, photopolymerizing by said light source and further coating or printing, with or without careful finishing of the article, is a further subject of the present invention.

[0125] As mentioned above, the inventors have surprisingly found that the compounds of formula (I) have very high reactivity under UVA, UVB and UVC wavelengths while retaining low post-cure yellowing compared to the prior art. The new compounds show a significant improvement in surface curability under Hg lamps in both clear and pigmented systems.

[0126] The present invention will now be described in more detail with reference to the following examples, which are given for illustrative purposes and are not limiting.

[0127] [Experimental section] In the event of a conflict between the chemical name and the chemical structure presented herein, the chemical structure shall control. 1 1 H NMR spectra were recorded on a Bruker Ascend 300 MHz NMR spectrometer. The letters "a" through "f" represent the number of ethoxy units.

[0128] [Intermediate 1] [ka] To an ice-cooled mixture of 5.00 g (26.843 mmol) of diphenyl sulfide and 3.98 g (26.870 mmol) of phthalic anhydride in 90 mL of chlorobenzene was carefully added 7.15 g (53.622 mmol) of anhydrous aluminum chloride in small portions. The reaction mixture was stirred at room temperature for 1.5 hours and then poured into ice / dilute hydrochloric acid. The mixture was extracted with ethyl acetate, the organic phase was separated, washed with 1M hydrochloric acid, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation to obtain a crude product. The resulting crude product was purified by crystallization from toluene to obtain 6.55 g of a white solid (73% yield). 1 H-NMR (DMSO-d6, δ ppm):7.24 (d, 2H), 7.40 (dd, 1H), 7.46-7.56 (m, 7H), 7.61-7.74 (m, 2H), 7.99 (dd, 1H)

[0129] [Intermediate 2] [ka] To an ice-cooled mixture containing 15.00 g (90.242 mmol) of fluorene and 13.36 g (90.197 mmol) of phthalic anhydride in 270 ml of chlorobenzene, 24.07 g (180.516 mmol) of anhydrous aluminum chloride was carefully added in small portions. The reaction mixture was stirred at room temperature for 1.5 hours and then poured into ice / dilute hydrochloric acid. The resulting semi-solid product was treated with 270 ml of ethyl acetate and the resulting solid was filtered. The filtrate was separated, washed with 1M hydrochloric acid, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation to obtain a crude product. The resulting crude product was purified by crystallization from toluene to obtain 6.55 g of a white solid (73% yield). The resulting composition was combined with the solid obtained from the previous filtration, suspended in 200 ml of toluene, and washed for 30 minutes under reflux and vigorous stirring. The mixture was then cooled and filtered to give 27.26 g of a white solid (96% yield). 1H-NMR (DMSO-d6, δ ppm):3.99 (s, 2H), 7.38-7.48 (m, 3H), 7.60-7.76 (m, 4H), 7.86 (s, 1H), 7.98-8.04 (m, 3H)

[0130] [Intermediate 3] [ka] To an ice-cooled mixture containing 15.00 g (88.126 mmol) of diphenyl ether and 13.05 g (88.104 mmol) of phthalic anhydride in 250 ml of chlorobenzene, 23.50 g (176.241 mmol) of anhydrous aluminum chloride was carefully added in small portions. The reaction mixture was stirred at room temperature for 1.5 hours and then poured into ice / dilute hydrochloric acid. The mixture was extracted with ethyl acetate, the organic phase was separated, washed with 1M hydrochloric acid, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation to obtain a crude product. The resulting crude product was purified by crystallization from toluene to obtain 23.25 g of a white solid (yield 83%). 1 H-NMR (DMSO-d6, δ ppm):7.03 (d, 2H), 7.14 (m, 2H), 7.25 (m, 1H), 7.38-7.49 (m, 3H), 7.62-7.75 (m, 4H), 7.98 (dd, 1H)

[0131] [Intermediate 4] [ka] To an ice-cooled mixture containing 5.15 g (24.491 mmol) of 9,9-dimethylxanthene and 3.63 g (24.507 mmol) of phthalic anhydride in 85 mL of chlorobenzene was carefully added 6.53 g (48.973 mmol) of anhydrous aluminum chloride in small portions. The reaction mixture was stirred at room temperature for 1.5 hours and then poured into ice / dilute hydrochloric acid. The mixture was extracted with ethyl acetate, the organic phase was separated, washed with 1 M hydrochloric acid, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation to give a crude product. The resulting crude product was purified by crystallization from toluene to give 7.15 g of a white solid (81% yield). 1 H-NMR (DMSO-d6, δ ppm):1.58 (s, 6H), 7.09-7.20 (m, 3H), 7.28 (m, 1H), 7.38-7.46 (m, 2H), 7.58 (dd, 1H), 7.62-7.78 (m, 2H), 7.93 (d, 1H), 8.00 (dd, 1H)

[0132] [Intermediate 5] [ka] To an ice-cooled mixture containing 15.00 g (76.817 mmol) of 9-ethylcarbazole and 5.69 g (38.415 mmol) of phthalic anhydride in 250 ml of chlorobenzene was carefully added 5.12 g (38.398 mmol) of anhydrous aluminum chloride in small portions. The reaction mixture was stirred at room temperature for 1 hour, then the reaction mixture was cooled again and an additional 2.84 g (19.174 mmol) of phthalic anhydride and 2.56 g (19.199 mmol) of anhydrous aluminum chloride were added in sequence. The reaction mixture was stirred at room temperature for an additional hour, then the reaction mixture was cooled again and an additional 1.42 g (9.587 mmol) of phthalic anhydride and 1.28 g (9.600 mmol) of anhydrous aluminum chloride were added in sequence. The reaction mixture was stirred at room temperature for an additional hour and then poured into ice / dilute hydrochloric acid. The mixture was extracted with ethyl acetate, the organic phase was separated, washed with 1M hydrochloric acid, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation to obtain a crude product. The crude product was suspended in 250 ml of toluene and washed for 30 minutes under reflux and vigorous stirring. The mixture was then cooled and the solid was filtered. The solid was suspended in 200 ml of toluene and washed again under reflux and vigorous stirring for 24 hours. The mixture was then cooled and the solid was filtered to obtain 7.61 g of a white solid (33% yield). 1 H-NMR (DMSO-d6, δ ppm):1.34 (t, 3H), 4.49 (q, 2H), 7.23 (t, 1H), 7.44-7.55 (m, 2H), 7.64-7.77 (m, 5H), 8.01 (dd, 1H), 8.20 (d, 1H), 8.50 (d, 1H)

[0133] [Intermediate 6] [ka] To an ice-cooled mixture containing 15.00 g (61.145 mmol) of triphenylamine and 4.53 g (30.583 mmol) of phthalic anhydride in 200 ml of chlorobenzene was carefully added 4.07 g (30.523 mmol) of anhydrous aluminum chloride in small portions. The reaction mixture was stirred at room temperature for 1 hour, then the reaction mixture was cooled again and an additional 2.27 g (15.325 mmol) of phthalic anhydride and 2.04 g (15.299 mmol) of anhydrous aluminum chloride were added in sequence. The reaction mixture was stirred at room temperature for an additional hour, then the reaction mixture was cooled again and an additional 1.89 g (12.760 mmol) of phthalic anhydride and 1.70 g (12.749 mmol) of anhydrous aluminum chloride were added in sequence. The reaction mixture was stirred at room temperature for an additional hour and then poured into 400 ml of ice / water. The mixture was extracted with ethyl acetate, the organic phase was separated, dried over anhydrous sodium sulfate, filtered, and the solvent was removed by vacuum distillation to give the crude product, which was purified by flash chromatography on silica gel (toluene / ethyl acetate; 50:50) to give 7.85 g of a yellow solid (34% yield). 1 H-NMR (DMSO-d6, δ ppm):6.83 (d, 2H), 7.10-7.28 (m, 6H), 7.33-7.43 (m, 5H), 7.49 (d, 2H), 7.56-7.71 (m, 2H), 7.97 (dd, 1H) EXAMPLES

[0134] [ka] (In the formula, [ka] ) 3.00 g (8.972 mmol) of "Intermediate 1", 1.52 g (hydroxyl value 364 / g) of polyhol 3380 (purchased from PERSTORP) and 0.171 g (0.899 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 mL of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 mL of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 mL of saturated sodium bicarbonate solution and 30 mL of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.35 g of a colorless oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):0.70 (m, 3H), 1.18 (m, 2H), 3.00-3.70 (m, 33H), 3.85-4.35 (m, 5H), 7.10-7.32 (m, 5H), 7.32-7.60 (m, 20H), 7.60-7.85 (m, 5H), 7.85-8.02 (m, 2.5H) EXAMPLES

[0135] [ka] (where: [ka] ) 3.00 g (9.424 mmol) of "Intermediate 3", 0.918 g (hydroxyl value 634 / g) polyhol 4640 (purchased from PERSTORP) and 0.179 g (0.941 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 mL of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 mL of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 mL of saturated sodium bicarbonate solution and 30 mL of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 3.74 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):2.98-3.70 (m, 5.7H), 3.81-4.35 (m, 2H), 6.80-7.28 (m, 5H), 7.30-7.80 (m, 7H), 7.80-8.06 (m, 1H) EXAMPLES

[0136] [ka] (where: [ka] ) 3.00 g (9.424 mmol) of "Intermediate 3", 1.56 g (hydroxyl value 370 / g) of AIONICO GL / 609 (purchased from Lamberti SpA) and 0.179 g (0.941 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.39 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):3.03-3.78 (m, 11.45H), 4.00-4.38 (m, 2H), 6.91-7.20 (m, 4H), 7.32-7.57 (m, 4H), 7.57-7.86 (m, 4H), 7.86-8.03 (m, 1H) EXAMPLES

[0137] [ka] (where: [ka] ) 3.00 g (8.371 mmol) of "Intermediate 4", 1.39 g (hydroxyl value 370 / g) of AIONICO GL / 609 (purchased from Lamberti SpA) and 0.159 g (0.836 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.24 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):1.60 (m, 6H), 3.05-3.75 (m, 11.5H), 3.91-4.30 (m, 2H), 7.00-7.32 (m, 3H), 7.36-7.60 (m, 3H), 7.60-7.85 (m, 3H), 7.88-8.03 (m, 2H) EXAMPLES

[0138] [ka] (where: [ka] ) 3.00 g (9.544 mmol) of "Intermediate 2", 1.66 g (hydroxyl value 370 / g) of AIONICO GL / 609 (purchased from Lamberti SpA) and 0.182 g (0.957 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.49 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):3.05-3.78 (m, 10.15H), 3.79-4.35 (m, 4H), 7.28-7.81 (m, 7H), 7.81-8.08 (m, 4H) EXAMPLES

[0139] [ka] (where: [ka] ) 3.00 g (7.625 mmol) of "Intermediate 6", 1.27 g (hydroxyl value 370 / g) of AIONICO GL / 609 (purchased from Lamberti SpA) and 0.145 g (0.762 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 3.70 g of a yellow oil (90% yield). 1 H-NMR (DMSO-d6, δ ppm):3.10-3.78 (m, 11.55H), 4.00-4.56 (m, 2H), 6.70-7.54 (m, 15H), 7.54-8.00 (m, 3H) EXAMPLES

[0140] [ka] (where: [ka] ) 3.00 g (9.544 mmol) of "Intermediate 2", 2.14 g (hydroxyl value 300 / g) of sorbilene RE / 20 (purchased from Lamberti SpA) and 0.182 g (0.957 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.96 g of a brown-yellow oil (100% yield). 1H-NMR (DMSO-d6, δ ppm):3.00-3.75 (m, 14.47H), 3.78-4.30 (m, 4H), 7.26-7.81 (m, 7H), 7.81-8.06 (m, 4H) EXAMPLES

[0141] [ka] (where: [ka] ) 3.00 g (8.972 mmol) of "Intermediate 1", 1.50 g (hydroxyl value 370 / g) of AIONICO GL / 609 (purchased from Lamberti SpA) and 0.171 g (0.899 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.34 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):3.05-3.75 (m, 11.6H), 4.00-4.30 (m, 2H), 7.10-7.83 (m, 12H), 7.83-8.03 (m, 1H) EXAMPLES

[0142] [ka] (where: [ka] ) 3.00 g (8.737 mmol) of "Intermediate 5", 1.52 g (hydroxyl value 370 / g) of AIONICO GL / 609 (purchased from Lamberti SpA) and 0.166 g (0.873 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.28 g of a yellow-orange oil (98% yield). 1 H-NMR (DMSO-d6, δ ppm):1.25 (m, 3H), 2.90-3.79 (m, 10.15H), 3.90-4.62 (m, 4H), 7.04-7.29 (m, 1H), 7.30-7.82 (m, 7H), 7.82-8.58 (m, 3H) EXAMPLES

[0143] [ka] (where: [ka] ) 3.00 g (8.972 mmol) of "Intermediate 1", 0.942 g (4.710 mmol) of polyethylene glycol (average molecular weight 200) and 0.171 g (0.899 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 3.78 g of a colorless oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):3.20-3.75 (m, 6.4H), 4.00-4.38 (m, 2H), 7.10-7.83 (m, 12H), 7.88-8.02 (m, 1H) EXAMPLES

[0144] [ka] (where: [ka] ) 3.00 g (9.544 mmol) of "Intermediate 2", 1.000 g (5.000 mmol) of polyethylene glycol (average molecular weight 200) and 0.182 g (0.957 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 3.83 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):3.15-3.75 (m, 4.4H), 3.80-4.38 (m, 4H), 7.30-7.53 (m, 3H), 7.53-7.82 (m, 4H), 7.87 (m, 1H), 7.90-8.07 (m, 3H) EXAMPLES

[0145] [ka] (where: [ka] ) 3.00 g (9.544 mmol) of "Intermediate 2", 1.691 g (hydroxyl value 364 / g) of polyhol 3380 (purchased from PERSTORP) and 0.182 g (0.957 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 mL of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 mL of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 mL of saturated sodium bicarbonate solution and 30 mL of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.52 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):0.44-0.91 (m, 3H), 1.00-1.45 (m, 2H), 2.88-3.75 (m, 33.5H), 3.76-4.38 (m, 9H), 7.30-7.44 (m, 4.5H), 7.44-7.81 (m, 11.25H), 7.81-8.09 (m, 9H) EXAMPLES

[0146] [ka] (where: [ka] ) 3.00 g (8.972 mmol) of "Intermediate 1", 1.645 g (3.290 mmol) of Polyglycol G 500 (purchased from Clariant) and 0.171 g (0.899 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (15:15), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.48 g of a pale oil (100% yield). 1 H-NMR (DMSO-d6, δ ppm):3.05-3.75 (m, 13H), 4.00-4.40 (m, 2H), 7.10-7.84 (m, 12H), 7.86-8.02 (m, 1H) EXAMPLES

[0147] [ka] (where: [ka] ) 3.00 g (9.544 mmol) of "Intermediate 2", 1.829 g (3.658 mmol) of Polyglycol G 500 (purchased from Clariant) and 0.182 g (0.957 mmol) of p-toluenesulfonic acid monohydrate were mixed in 5 ml of toluene and refluxed until all water was removed by azeotropic distillation. The reaction mixture was then cooled, diluted with ethyl acetate and washed successively with 30 ml of a mixture of saturated sodium bicarbonate solution / water (1:1), 30 ml of saturated sodium bicarbonate solution and 30 ml of water. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and the solvent was removed by vacuum distillation to give 4.66 g of a pale oil (100% yield). 1H-NMR (DMSO-d6, δ ppm):3.05-3.75 (m, 11.7H), 3.80-4.36 (m, 4H), 7.28-7.82 (m, 7H), 7.82-8.06 (m, 4H)

[0148] [Comparative Example 1] [ka] (where: [ka] ) The compound of Comparative Example 1 was synthesized as disclosed in WO 2015 / 010729.

[0149] [Test example 1] yellowness Yellowing was measured as Yellowness Index (YI) using BYK Color Guide 45 / 0. Test samples were prepared as follows: 3% by weight of photoinitiator, 3% by weight of co-initiator (Esacure A198) and 0.5% by weight of Omnirad ITX (obtained from IGM Resins BV) were added to a formulation containing 50% by weight of Photomer 6577, 15% by weight of Photomer 4335, 15% by weight of Photomer 4666 and 20% by weight of Photomer 4172 and stirred at 60° C. for 1 hour. The formulation thus obtained was spread on a varnished cardboard with a thickness of 12 microns using a bar coater and was then exposed to a LED lamp (16 W / cm 2 ) at the maximum speed at which tack-free was achieved. 2 The yellowing was then measured as the yellowness index (YI), and the results are shown in Table 1. [Table 1] The above tests confirm that the compounds of formula (I) surprisingly exhibit very low yellowing after curing with respect to the comparative compounds, in some cases the yellowness index is as much as 2 points lower, which is a particularly remarkable result.

[0150] [Test example 2] Through cure in cyan offset ink under Hg lamp Test formulations were prepared by dissolving the photoinitiator in an industrial cyan offset ink at a concentration of 3% by weight. The same amount (3% by weight) of co-initiator (Esacure A198) was added to the composition. The test formulations were homogenized with a mechanical stirrer at 50°C for 1 hour and coated at a thickness of 1.5 microns onto white cardboard using an IGT repro-tester device. The coating was then heated to 30°C for 1 hour ... 2 ) was used to cure the formulation. The through cure test is a measurement of the complete ink cure obtained at a defined speed, checked by the "thumb twist pressure test". A faster speed corresponds to a higher reactivity. The results are shown in Table 2. [Table 2] This result again confirms the very good performance of the photoinitiators of the present invention.

[0151] [Test example 3] Surface curing of cyan offset ink under LED 365 nm lamp Test formulations were prepared by dissolving the photoinitiator in an industrial cyan offset ink at a concentration of 3% by weight. Co-initiator (Esacure A198) was added in equal amounts (3% by weight) and Omnirad ITX at 0.5% by weight to the composition. The test formulations were homogenized with a mechanical stirrer at 50°C for 1 hour and coated at a thickness of 1.5 microns onto white cardboard using an IGT repro-tester device. LED 365 nm lamp (12 W / cm 2 ) was used to cure the formulation. The evaluation was carried out taking into account the number of passes at a speed of 100 m / min to obtain a dry surface (cotton test): the fewer the number of passes, the better the surface cure. The results are shown in Table 3. [Table 3] This test also confirms that the compounds of formula (I) are more effective than comparative compounds of the prior art.

Claims

1. A compound of formula (I). Formula (I) 【Chemistry 1】 [where: G is an optionally ethoxylated and / or propoxylated monomeric, oligomeric, or polymeric polyol G-(OH) n+p is a residue of n is 1 to 8; p is 0 to 7; n+p is 2 to 8; and Z is represented by the following formulae (i), (ii) and (iii): 【Chemistry 2】 (where: X, Y and W are each independently selected from O, S and C(R2)(R3); R1 is hydrogen, halogen, substituted or unsubstituted C1-C20 alkyl, C5-C7 cycloalkyl, C3-C12 alkenyl, -O(C3-C12 alkenyl), -S(C3-C12 alkenyl), aryl, substituted or unsubstituted C1-C20 alkoxy, C1-C50 alkyl interrupted by one or more oxygen atoms, C5-C7 cycloalkoxy, aryloxy, substituted or unsubstituted C1-C20 alkylthio, arylthio, substituted or unsubstituted (C1-C12 alkyl). 2 Amino, (C5-C7 cycloalkyl) 2 Selected from amino, morpholino, piperidino, piperazino, and N(C1-C12 alkyl)piperazino; R2 and R3 are each independently selected from H, C1-C12 alkyl, OH, and C1-C10 alkoxy; and The wavy line represents the bond connected to the keto group in formula (I). are selected from.

2. 2. The compound according to claim 1, characterized in that G-(OH)n+p is selected from monomeric, oligomeric, polymeric polyols and mixtures thereof, optionally ethoxylated and / or propoxylated, n is from 1 to 6, preferably from 2 to 6, more preferably from 2 to 6, most preferably from 3 to 5; p is from 0 to 6, more preferably from 0 to 3; and n+p is from 2 to 8, more preferably from 3 to 6.

3. The compound according to claim 1, characterized in that Z is (i) or (iii).

4. The compound according to claim 1, characterized in that Z is (i) and X is S or O, or Z is (iii) and W is C(R2)(R3).

5. a) 50 to 99.9% by weight, preferably 70 to 98.9% by weight (based on the total weight of the composition) of at least one ethylenically unsaturated compound; b) 0.1 to 35% by weight, preferably 0.1 to 20% by weight, more preferably 0.2 to 15% by weight (based on the total weight of the composition) of at least one compound of formula (I) as defined in claim 1; and c) Accelerators and / or coinitiators: 0 to 20% by weight, preferably 0.2 to 15% by weight, more preferably 0.2 to 15% by weight (based on the total weight of the composition) A photopolymerizable composition comprising:

6. In addition, the following ingredients: d) 0.01 to 15% by weight (based on the total content of the composition) of one or more photosensitizers; and / or e) 0.5 to 15% by weight (based on the total content of the composition) of one or more further photoinitiators The photocurable composition of claim 5 comprising one or more of the following:

7. 1. A method for photocuring photopolymerizable compositions, coatings, adhesives and inks comprising: (i) providing a photopolymerizable composition according to claim 5 or 6; (ii) coating or printing the photopolymerizable composition onto a substrate; and (iii) photopolymerizing the coated or printed composition on the substrate with a light source. The method comprising:

8. 7. A method of three-dimensional printing comprising providing a photopolymerizable composition according to claim 5 or 6 and photocuring said composition with a light source.

9. 8. The method of claim 7, wherein the light source comprises UV light in at least one of the UVA, UVB, and UVC regions.

10. 8. The method of claim 7, wherein the light source is an LED source emitting in the range of 350 to 420 nm.

11. 9. The method of claim 8, wherein the light source comprises UV light in at least one of the UVA, UVB, and UVC regions.

12. 9. The method of claim 8, wherein the light source is an LED source emitting in the range of 350 to 420 nm.

13. 9. The method of claim 8, further comprising the step of applying the photopolymerizable composition to a substrate prior to photopolymerization.

14. An industrial product obtained according to the method of claim 7.

15. An industrial product obtained according to the method of claim 8.

16. An industrial product obtained according to the method of claim 13.

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