JP7371554B2 - Bisoxime ester photopolymerization initiator, polymerizable composition, cured product and method for producing the same - Google Patents

Description

The present invention relates to a bisoxime ester photopolymerization initiator, a polymerizable composition, a cured product, and a method for producing the same.

Radical polymerization initiators that generate radicals by heat, light, or oxidation-reduction are widely used as polymerization initiators to synthesize polymers and the like. In particular, photopolymerization initiators can generate radicals by bond cleavage and hydrogen abstraction from substrates by absorbing active energy rays such as light. used as. For example, oxime ester derivatives, α-hydroxyacetophenone derivatives, α-aminoacetophenone derivatives, acylphosphine oxide derivatives, halomethyltriazine derivatives, benzyl ketal derivatives, thioxanthone derivatives, etc. are used.

Photopolymerizable compositions consisting of a photopolymerization initiator and a radically polymerizable compound as described above are rapidly cured by light irradiation, so they can be used as coating agents, paints, printing inks, photosensitive printing plates, adhesives, and various photoresists. It is applied for such purposes.

Patent Documents 1 to 4 describe oxime ester derivatives, and these oxime ester derivatives are known to be used as highly sensitive photopolymerization initiators in black resists, color resists, and the like.

Special Publication No. 2012-526185 Special table 2017-512886 publication China Patent Publication No. 109666088 Japanese Patent Application Publication No. 2007-269779

In recent years, high color purity has been required for liquid crystal display panels, etc., and the content of pigments has increased in the production of color resists, so the content of photopolymerization initiators has increased to maintain curability. There is a tendency. However, the monofunctional oxime ester photopolymerization initiator having a cycloalkyl group in the side chain described in Patent Document 1 has insufficient sensitivity, and a large amount of the initiator must be blended in order to maintain curability. Therefore, as the content of the photopolymerization initiator increases, the coloring of the cured product becomes stronger, which adversely affects the color reproducibility of liquid crystal display panels and the like.

Further, as a highly sensitive photopolymerization initiator, bisoxime ester photopolymerization initiators having two oxime ester groups in one molecule have been proposed as described in Patent Documents 2 to 4. However, since the compounds described in Patent Documents 2 to 4 have highly crystalline structures, they have low solubility in solvents, so there is a problem that a sufficient amount of photopolymerization initiator cannot be blended.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a photopolymerization initiator that is highly sensitive to light having a wavelength of 365 nm, etc., and has high solubility.

（Ｒ^１及びＲ^２は、独立して炭素数が１～８の直鎖または分岐鎖のアルキル基である。また、Ｒ^１及びＲ^２は、同一でない。Ｒ^３は、独立して炭素数が１～８の直鎖もしくは分岐鎖のアルキル基、または炭素数が１～８のアルコキシ基である。）で表される構造を有するビスオキシムエステル系光重合開始剤に関する。 That is, the present invention provides general formula (I):

(R ¹ and R ² are independently linear or branched alkyl groups having 1 to 8 carbon atoms. R ¹ and R ² are not the same. R ³ is independently a straight chain or branched alkyl group having 1 to 8 carbon atoms. is a linear or branched alkyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms.

The present invention also relates to a polymerizable composition containing the bisoxime ester photopolymerization initiator and a radically polymerizable compound, a cured product formed from the polymerizable composition, and a method for producing the same.

Although the details of the mechanism of action of the bisoxime ester photopolymerization initiator according to the present invention are unclear, it is presumed as follows. However, the present invention is not limited to this mechanism of action.

The bisoxime ester photopolymerization initiator of the present invention can efficiently absorb light of 365 nm or the like emitted from a light source to efficiently generate radicals, and has an asymmetric structure, so it has excellent solubility. Therefore, the polymerizable composition containing the bisoxime ester photopolymerization initiator and the radically polymerizable compound can be well cured by light irradiation.

（Ｒ^１及びＲ^２は、独立して炭素数が１～８の直鎖または分岐鎖のアルキル基である。また、Ｒ^１及びＲ^２は、同一でない。Ｒ^３は、独立して炭素数が１～８の直鎖もしくは分岐鎖のアルキル基、または炭素数が１～８のアルコキシ基である。） <Bisoxime ester photopolymerization initiator>
The bisoxime ester photopolymerization initiator of the present invention can be represented by the following general formula (1).

(R ¹ and R ² are independently linear or branched alkyl groups having 1 to 8 carbon atoms. R ¹ and R ² are not the same. R ³ is independently a straight chain or branched alkyl group having 1 to 8 carbon atoms. is a linear or branched alkyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms.)

In the general formula (1), R ¹ and R ² are, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-hexyl group. , n-octyl group, isooctyl group, 2-ethylhexyl group, and 1,3,3-trimethylbutyl group. Furthermore, from the viewpoint of forming an asymmetric structure and increasing solubility, either one of R ¹ or R ² is preferably a methyl group. Further, R ³ is, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, an n-octyl group, an isooctyl group, Examples include alkyl groups such as 2-ethylhexyl group and 1,3,3-trimethylbutyl group; and alkoxy groups such as methoxy group and ethoxy group. Further, R ³ is preferably a methyl group from the viewpoint of increasing sensitivity.

Specific examples of the bisoxime ester photopolymerization initiator of the present invention are shown below, but the present invention is not limited thereto.

<Method for producing bisoxime ester photopolymerization initiator>
The method for producing the bisoxime ester photopolymerization initiator is not particularly limited, and for example, a) diphenylthioether is used as a starting material, and the starting material and an acyl halide having R ¹ group are reacted with aluminum chloride or the like, a) a step of synthesizing intermediate I in which intermediate I of the ketoxime ester photoinitiator is synthesized by ^a Friedel-Crafts reaction; c) Subsequently, Intermediate II and isoamyl nitrite are reacted with Friedel-Crafts to synthesize Intermediate II of the ketoxime ester photoinitiator, and c) d) a synthesis step of intermediate III in which intermediate III, which is a hydroxylamine compound, is produced by oxidation reaction in the presence of a catalyst such as sodium alcoholate, potassium alcoholate, etc.; and d) intermediate III and acetyl chloride or anhydride. Examples include a method including a step of synthesizing a bisoxime ester photoinitiator by esterifying it to synthesize a bisoxime ester photoinitiator.

In step a, for example, the starting materials, aluminum chloride, and organic solvent A are stirred and mixed, the temperature is cooled to 0° C., and then a mixed solution of an acyl halide having R ¹ group and organic solution A is added dropwise. Then, adjust the temperature to a range of 0 to 10°C, add dropwise over 0.5 to 2 hours, maintain the temperature at 0 to 30°C, and continue stirring for 1 to 3 hours to obtain a reaction solution. . The obtained reaction solution is subjected to a washing treatment, etc., to obtain a white solid intermediate I. The molar ratio between the starting material and aluminum chloride (starting material/aluminum chloride) is usually about 0.1 to 1.5, preferably about 0.5 to 1.0. Further, the molar ratio between the starting material and the acyl halide having R ¹ group (starting material/acyl halide having R ¹ group) is usually about 0.1 to 1.5, and 0.5 to 1.0. It is preferable that the degree of

Examples of the organic solvent A include dichloroethane, dichloromethane, and carbon tetrachloride.

In step b, for example, the intermediate I, aluminum chloride, and the organic solvent A are stirred and mixed, the temperature is cooled to 0° C., and then the acyl halide having R ² groups and the organic solution A are mixed. The mixed solution was added dropwise, the temperature was adjusted to a range of 0 to 10°C, and the dropwise addition took 0.5 to 2 hours.The temperature was maintained at 0 to 30°C, and the mixture was continuously stirred for 1 to 3 hours. , obtain a reaction solution. The obtained reaction solution is subjected to washing treatment and the like to obtain a white solid intermediate II. The molar ratio between Intermediate I and aluminum chloride (Intermediate I/aluminum chloride) is usually about 0.1 to 1.5, preferably about 0.1 to 0.5. Further, the molar ratio between intermediate I and acyl halide having ² R groups (intermediate I/acyl halide having ² R groups) is usually about 0.1 to 1.5, and 0.5 to 1 It is preferable that it is about .0.

In step c, for example, a catalyst such as hydrogen chloride is added to a mixed solution of intermediate II produced in step b, organic solvent B, and isoamyl nitrite, and the mixture is reacted for 1 to 10 hours with stirring at room temperature. to obtain a reaction solution. The obtained reaction solution is subjected to washing treatment and the like to obtain intermediate III as a viscous liquid. The molar ratio of intermediate II and isoamyl nitrite (intermediate II/isoamyl nitrite) is usually about 0.2 to 0.5, preferably about 0.2 to 0.3.

Examples of the organic solvent B include dichloroethane and tetrahydrofuran.

In step d, for example, intermediate III produced in step b, an amine catalyst such as pyridine, and the above organic solvent B are stirred and mixed, the temperature is cooled to 0° C., and then acetyl chloride or anhydride is mixed. A solution containing organic solvent B and organic solvent B is started to be added dropwise over a period of 0.5 to 1.5 hours, and then stirred for 1 to 4 hours to obtain a reaction solution. The obtained reaction solution is subjected to washing treatment and the like to obtain a bisoxime ester photoinitiator. The molar ratio of intermediate III and acetyl chloride or anhydride (intermediate III/acetyl chloride or anhydride) is usually about 0.2 to 0.5, and should be about 0.2 to 0.3. is preferred.

<Polymerizable composition>
The polymerizable composition of the present invention contains a polymerization initiator including the bisoxime ester photopolymerization initiator and a radically polymerizable compound. Furthermore, the polymerizable composition can impart developability by containing an alkali-soluble resin. Moreover, the polymerizable composition can contain other components in appropriate combination.

<Polymerization initiator>
The polymerization initiator of the present invention contains the bisoxime ester photopolymerization initiator. The polymerization initiator is decomposed by active energy rays, and the generated radicals have the function of initiating polymerization (curing) of a radically polymerizable compound. The bisoxime ester photopolymerization initiator may be used alone or in combination of two or more types.

Further, the polymerization initiator may contain a polymerization initiator other than the bisoxime ester photopolymerization initiator (hereinafter also referred to as other polymerization initiator). By using two or more types of bisoxime ester photopolymerization initiators or other polymerization initiators with different absorption bands, for example, it is possible to improve the polymerizability of lamps that emit light of multiple wavelengths, such as high-pressure mercury lamps. High sensitivity of the composition can be achieved. In addition, considering the polymerizability of the radically polymerizable compound contained in the polymerizable composition, the type of pigment that absorbs or scatters light contained in the polymerizable composition, the film thickness of the cured product, etc., other polymerization initiation methods are determined. By using the agent, the surface curability, deep curability, transparency, etc. of the polymerizable composition can be improved.

As the other polymerization initiators, known ones can be used, such as 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-propiophenone, 4'-(2-hydroxyethoxy)-2-hydroxy -2-Methylpropiophenone, α-hydroxyacetophenone derivatives such as 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one, etc. ;2-Methyl-4'-methylthio-2-morpholinopropiophenone, 2-benzyl-2-(N,N-dimethylamino)-1-(4-morpholinophenyl)butan-1-one, 2-(dimethyl α-Aminoacetophenone derivatives such as amino)-2-(4-methylbenzyl)-1-(4-morpholinophenyl)butan-1-one; diphenyl-2,4,6-trimethylbenzoylphosphine oxide, phenylbis(2 , 4,6-trimethylbenzoyl)phosphine oxide, ethyl (mesitylcarbonyl) phenylphosphinate and other acylphosphine oxide derivatives; 1-[4-(phenylthio)phenyl]octane-1,2-dione-2-(O 2- (4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(3,4-dimethoxystyryl)-4,6-bis(trichloromethyl)1,3,5 -Triazine, halomethyltriazine derivatives such as 2-(4-ethoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine; 2,2-dimethoxy-2-phenylacetophenone, etc. benzyl ketal derivatives; thioxanthone derivatives such as isopropylthioxanthone; benzophenone derivatives such as 4-(4-methylphenylthio)benzophenone; 3-benzoyl-7-diethylaminocoumarin, 3,3'-carbonylbis(7-diethylaminocoumarin), etc. Coumarin derivatives; imidazole derivatives such as 2-(2-chlorophenyl)-1-[2-(2-chlorophenyl)-4,5-diphenyl-1,3-diazol-2-yl]-4,5-diphenylimidazole; Organic peroxides such as 3,3',4,4'-tetrakis(tert-butylperoxycarbonyl)benzophenone and dibenzoyl peroxide; azo compounds such as azobisisobutyronitrile; and camphorquinone. Other polymerization initiators may be used alone or in combination of two or more.

<Radical polymerizable compound>
As the radically polymerizable compound of the present invention, a compound having an ethylenically unsaturated group can be preferably used. Examples of the radically polymerizable compounds include (meth)acrylic esters, styrenes, maleic esters, fumaric esters, itaconic esters, cinnamic esters, crotonic esters, vinyl ethers, and vinyl esters. Examples include esters, vinyl ketones, allyl ethers, allyl esters, N-substituted maleimides, N-vinyl compounds, unsaturated nitriles, and olefins. Among these, it is preferable to include highly reactive (meth)acrylic esters. The radically polymerizable compounds may be used alone or in combination of two or more.

As the (meth)acrylic esters, monofunctional compounds and polyfunctional compounds can be used. Monofunctional compounds include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, and stearyl (meth)acrylate. Alkyl (meth)acrylates such as acrylate; cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth) Ester compounds of (meth)acrylic acid and alicyclic alcohol such as acrylate and 2-ethyl-2-adamantyl (meth)acrylate; aryl (meth)acrylates such as phenyl (meth)acrylate and benzyl (meth)acrylate ; 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 3-hydroxy-1-adamantyl (meth)acrylate, polyethylene glycol mono(meth)acrylate Monomers with hydroxy groups such as acrylate and polypropylene glycol mono(meth)acrylate; methoxyethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, 2-phenylphenoxyethyl (meth)acrylate, Tetrahydrofurfuryl (meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, cyclic Monomers having a chain or cyclic ether bond such as trimethylolpropane formal (meth)acrylate; N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethyl (meth)acrylamide, N-methylol (meth)acrylate Nitrogen atoms such as acrylamide, N-isopropyl (meth)acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, diacetone (meth)acrylamide, (meth)acryloylmorpholine, N-(meth)acryloyloxyethylhexahydrophthalimide, etc. Monomers having isocyanate groups such as 2-(meth)acryloyloxyethyl isocyanate; Monomers having epoxy groups such as glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether; Phosphoric acid 2-(( Monomers having a phosphorus atom such as meth)acryloyloxy)ethyl; monomers having a silicon atom such as 3-(meth)acryloxypropyltrimethoxysilane; 2,2,2-trifluoroethyl (meth)acrylate, 2,2 , 3,3,3-pentafluoropropyl (meth)acrylate, 2-(perfluorohexyl)ethyl (meth)acrylate, and other fluorine atom-containing monomers; (meth)acrylic acid, succinic acid mono(2-(meth)acrylate) Contains carboxyl groups such as mono(acryloyloxyethyl) phthalate (2-(meth)acryloyloxyethyl), mono(2-(meth)acryloyloxyethyl) maleate, and ω-carboxy-polycaprolactone mono(meth)acrylate. Examples include monomers.

Examples of the polyfunctional compound include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, 1,4 -Butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, glycerin di(meth)acrylate, glycerin tri(meth)acrylate, glycerin propoxytri (meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane ethylene oxide modified tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, Pentaerythritol di(meth)acrylate monostearate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate Acrylate, 2,2-bis(4-(meth)acryloxyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloxypolyethoxyphenyl)propane, 9,9-bis(4-(2- (meth)acryloyloxyethoxy)phenyl)fluorene, 9,9-bis(4-(2-(2-(meth)acryloyloxyethoxy)ethoxy)phenyl)fluorene, and (meth)acrylic acid. Ester compounds; bis(4-(meth)acryloxyphenyl) sulfide, bis(4-(meth)acryloylthiophenyl) sulfide, tris(2-(meth)acryloyloxyethyl)isocyanurate, ethylene bis(meth)acrylamide , zinc (meth)acrylate, zirconium (meth)acrylate, aliphatic urethane acrylate, aromatic urethane acrylate, epoxy acrylate, polyester acrylate, and the like.

The above (meth)acrylic esters improve the sensitivity of the polymerizable composition, reduce curing inhibition caused by oxygen, and improve the mechanical strength, hardness, heat resistance, durability, and chemical resistance of the cured coating. From this point of view, ester compounds of the polyhydric alcohol and (meth)acrylic acid are preferred, particularly trimethylolethane triacrylate, trimethylolpropane triacrylate, trimethylolpropane ethylene oxide modified tri(meth)acrylate, and pentaerythritol triacrylate. , pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are preferred.

The content of the polymerization initiator is preferably from 0.1 to 40 parts by mass, more preferably from 0.5 to 20 parts by mass, and from 1 to 20 parts by mass, based on 100 parts by mass of the radically polymerizable compound. More preferably, the amount is 15 parts by mass. If the content of the polymerization initiator is less than 0.1 parts by mass based on 100 parts by mass of the radically polymerizable compound, the curing reaction will not proceed, which is not preferable. In addition, when the content of the polymerization initiator is more than 40 parts by mass with respect to 100 parts by mass of the radically polymerizable compound, the solubility in the radically polymerizable compound reaches saturation, and when forming a film of the polymerizable composition, This is not preferable because crystals of the polymerization initiator may precipitate, causing a problem of roughening of the film surface, or the strength of the cured product may decrease due to an increase in decomposed residues of the polymerization initiator.

In addition, when the other polymerization initiator is included in the polymerization initiator, the proportion of the other polymerization initiator is preferably 50% by mass or less, and preferably 30% by mass or less in the polymerization initiator. More preferred.

<Alkali-soluble resin>
The polymerizable composition can be suitably used as a negative resist by further blending an alkali-soluble resin. As the alkali-soluble resin, those commonly used for negative resists can be used, and there are no particular limitations as long as the resin is soluble in an aqueous alkaline solution, but a resin containing a carboxyl group is preferable. The alkali-soluble resins may be used alone or in combination of two or more.

As the alkali-soluble resin, for example, a carboxyl group-containing (meth)acrylic acid ester copolymer, a carboxyl group-containing epoxy acrylate resin, etc. are preferably used.

The carboxyl group-containing (meth)acrylic acid ester copolymer includes at least one type selected from the monofunctional compounds of the (meth)acrylic acid esters described above (excluding the monomer having the carboxyl group), and (meth)acrylic acid ester copolymer. ) Acrylic acid, (meth)acrylic acid dimer, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinylbenzoic acid, cinnamic acid, mono(2-(meth)acryloyloxyethyl) succinate, monophthalic acid Ethylenically unsaturated groups such as (2-(meth)acryloyloxyethyl), mono(2-(meth)acryloyloxyethyl) maleate, ω-carboxy-polycaprolactone mono(meth)acrylate, and their acid anhydrides. It is a copolymer containing at least one kind selected from the carboxylic acids contained therein.

Examples of the carboxyl group-containing (meth)acrylic acid ester copolymer include copolymers of methyl methacrylate, cyclohexyl methacrylate, and methacrylic acid. Furthermore, styrene, α-methylstyrene, N-vinyl-2-pyrrolidone, N-methylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide, diethyl fumarate, diethyl itaconate, and the like may be copolymerized.

In addition, the above-mentioned carboxyl group-containing (meth)acrylic acid ester copolymer is suitable for the reaction of ethylenically unsaturated groups, etc., from the viewpoint of achieving both the developability of a negative resist and film properties such as heat resistance, hardness, and chemical resistance. A carboxyl group-containing (meth)acrylic acid ester copolymer in which a functional group is introduced into the side chain is also preferably used. As a method for introducing an ethylenically unsaturated group into the side chain described above, for example, an epoxy group may be added to a part of the carboxyl group of a carboxyl group-containing (meth)acrylic acid ester copolymer, such as glycidyl (meth)acrylate, etc. and a method of adding a compound having an ethylenically unsaturated group, or a method of adding an ethylenically unsaturated group-containing monocarboxylic acid such as methacrylic acid to a (meth)acrylic acid ester copolymer containing an epoxy group and a carboxyl group. , a method of adding a compound having an isocyanate group and an ethylenically unsaturated group in the molecule, such as 2-(meth)acryloyloxyethyl isocyanate, to a (meth)acrylic acid ester copolymer containing a hydroxyl group and a carboxyl group. .

As the carboxyl group-containing epoxy acrylate resin, a compound obtained by further reacting an epoxy acrylate resin, which is a reaction product of an epoxy compound and the ethylenically unsaturated group-containing carboxylic acid, with an acid anhydride is suitable.

Examples of the epoxy resin include (o, m, p-)cresol novolac type epoxy resin, phenol novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, trisphenolmethane type epoxy resin, bisphenylfluorene. Examples include molded epoxy resins. Epoxy resins may be used alone or in combination of two or more.

Examples of the acid anhydride include maleic anhydride, succinic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, and chlorindic anhydride. , trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride, itaconic anhydride, and the like.

Furthermore, when synthesizing a carboxyl group-containing epoxy acrylate resin, if necessary, a tricarboxylic acid anhydride such as trimellitic anhydride is used to hydrolyze the acid anhydride group remaining after the reaction, thereby adding carboxyl groups to the epoxy acrylate resin. can be increased. Furthermore, the number of ethylenic double bonds can be further increased by using maleic anhydride containing an ethylenically unsaturated group.

The acid value of the alkali-soluble resin is preferably from 20 to 300 mgKOH/g, more preferably from 40 to 180 mg/KOH. If the acid value is less than 20 mgKOH/g, the solubility in an alkaline aqueous solution is poor, making it difficult to develop unexposed areas, which is not preferable. In addition, if the acid value is more than 300 mgKOH/g, the exposed areas also tend to detach from the base material during development, which is not preferable.

The weight average molecular weight of the alkali-soluble resin is preferably from 1,000 to 100,000, and preferably from 1,500 to 30,000. If the weight average molecular weight is less than 1,000, the heat resistance and hardness of the exposed portion will be poor, which is not preferable. If the weight average molecular weight is greater than 100,000, it may be difficult to develop unexposed areas, which is not preferable. The weight average molecular weight can be measured by gel permeation chromatography (GPC). As an example, HLC-8220GPC (manufactured by Tosoh Corporation) is used as a GPC device, three TSKgelHZM-M (manufactured by Tosoh Corporation) are used as columns, tetrahydrofuran is used as a developing solvent, the column temperature is 40°C, and the flow rate is 0.3 ml/min. , an RI detector, a sample injection concentration of 0.5% by mass, and an injection volume of 10 microliters.The weight average molecular weight can be determined as a polystyrene equivalent.

Further, the proportion of the alkali-soluble resin is preferably 10 to 70% by mass, more preferably 15 to 60% by mass, based on the total solid content of the polymerizable composition. When the proportion is less than 10% by mass, developability is poor, which is not preferable. If the proportion is more than 70% by mass, it is not preferable because the reproducibility of pattern shape and heat resistance will deteriorate.

In addition, the alkali-soluble resin may be one obtained by isolating and purifying the alkali-soluble resin as an active ingredient after the synthesis reaction, or the reaction solution obtained by the synthesis reaction, its dried product, etc. can also be used as they are. .

As the other components, the polymerizable composition includes coating agents, paints, printing inks, photosensitive printing plates, adhesives, and those commonly used in various photoresists such as color resists and black resists. Additives can be added. Examples of additives include sensitizers (benzophenone derivatives such as 4,4'-bis(diethylamino)benzophenone; thioxanthone derivatives such as isopropylthioxanthone and diethylthioxanthone; anthracene derivatives such as 9,10-dibutoxyanthracene; coumarin, Coumarin derivatives such as ketocoumarin; acridine derivatives such as acridine orange and 9-phenylacridine; benzoic acid ester derivatives such as ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, and (2-dimethylamino)ethyl benzoate; Alkylamine derivatives such as triethanolamine and methyldiethanolamine; camphorquinone, etc.), polymerization inhibitors (p-methoxyphenol, hydroquinone, 2,6-di-t-butyl-4-methylphenol, phenothiazine, etc.), ultraviolet absorbers , infrared absorbers, light stabilizers, antioxidants, leveling agents, surface conditioning agents, surfactants, thickeners, antifoaming agents, adhesion promoters, plasticizers, epoxy compounds, thiol compounds, ethylenically unsaturated bonds resin, saturated resin, colored dye, fluorescent dye, pigment (organic pigment, inorganic pigment), carbon-based material (carbon fiber, carbon black, graphite, graphitized carbon black, activated carbon, carbon nanotube, fullerene, graphene, carbon micro coils, carbon nanohorns, carbon airgel, etc.), metal oxides (titanium oxide, iridium oxide, zinc oxide, alumina, silica, etc.), metals (silver, copper, etc.), inorganic compounds (glass powder, layered clay minerals, mica, talc) , calcium carbonate, etc.), dispersants, flame retardants, etc. The additives may be used alone or in combination of two or more.

The content of the additive is appropriately selected depending on the purpose of use and is not particularly limited, but it is usually preferably 500 parts by mass or less with respect to 100 parts by mass of the radically polymerizable compound. It is more preferable that the amount is 100 parts by mass or less.

A solvent can also be added to the polymerizable composition in order to improve the viscosity, paintability, and smoothness of the cured film. The solvent is one that can dissolve or disperse the polymerization initiator, the radically polymerizable compound, the alkali-soluble resin, and the other components, and is particularly limited as long as it evaporates at the drying temperature. It's not a thing.

Examples of the solvent include water, alcohol solvents, carbitol solvents, ester solvents, ketone solvents, ether solvents, lactone solvents, unsaturated hydrocarbon solvents, cellosolve acetate solvents, and carbitol acetate solvents. Examples include solvents, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, and the like. The solvent may be used alone or in combination of two or more.

The amount of the solvent used is preferably 10 to 1000 parts by mass, more preferably 20 to 500 parts by mass, based on 100 parts by mass of the solid content of the polymerizable composition.

<Method for preparing polymerizable composition>
When preparing the polymerizable composition, the polymerization initiator, the radically polymerizable compound, and if necessary, the alkali-soluble resin and other components are placed in a storage container, and the mixture is heated using a paint shaker, a bead mill, It may be dissolved or dispersed according to a conventional method using a sand grind mill, a ball mill, an attritor mill, a two-roll mill, a three-roll mill, or the like. Furthermore, if necessary, it may be filtered through a mesh or membrane filter.

In the preparation of the polymerizable composition, the polymerization initiator may be added to the polymerizable composition from the beginning, but if the polymerizable composition is to be stored for a relatively long time, it may be added immediately before use. It is preferable to dissolve or disperse a polymerization initiator in a radically polymerizable composition.

<Method for producing cured product>
The cured product of the present invention is formed from the polymerizable composition. The method for producing a cured product includes a step of applying the polymerizable composition to a base material and then irradiating the polymerizable composition with active energy rays.

Examples of the coating method include spin coating, bar coating, spray coating, dip coating, flow coating, slit coating, doctor blade coating, gravure coating, screen printing, offset printing, and inkjet coating. Various methods such as a printing method and a dispenser printing method can be used. Furthermore, the material of the base material is not limited, and examples thereof include glass, silicon, metal, and plastic. Further, the shape of the base material is not limited, and includes, for example, a film, a sheet, and a three-dimensional molded product.

The step of irradiating the polymerizable composition with active energy rays includes decomposing the polymerization initiator and polymerizing the radically polymerizable compound by irradiating the polymerizable composition with active energy rays such as electron beams, ultraviolet rays, visible light, and radiation. By doing so, a cured product can be obtained.

The active energy ray preferably has a wavelength of 250 to 450 nm, and more preferably has a wavelength of 300 to 410 nm from the viewpoint of rapid curing.

Examples of the light source for the light irradiation include a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, an ultraviolet electrodeless lamp, a light emitting diode (LED), a xenon arc lamp, a carbon arc lamp, sunlight, a YAG laser, etc. Solid state lasers, semiconductor lasers, gas lasers such as argon lasers, etc. can be used. In addition, when using visible light to infrared light that is poorly absorbed by the polymerization initiator, curing can be carried out by using a sensitizer that absorbs the light as the additive.

The exposure amount of the active energy rays should be appropriately set depending on the wavelength and intensity of the active energy rays and the composition of the polymerizable composition. As an example, the exposure amount in the UV-A region is preferably from 10 to 5,000 mJ/cm ² , more preferably from 30 to 1,000 mJ/cm ² .

Moreover, when the polymer composition contains the solvent, the method for producing the cured product can include a drying step. In particular, when applying the step of irradiating with the active energy rays after coating the polymerizable composition on the substrate, it is preferable to provide a drying step before the step of irradiating with the active energy rays.

In the drying step, methods for drying the solvent include, for example, heating drying, ventilation heating drying, reduced pressure drying, and the like. The heating drying method is not particularly limited, and examples thereof include an oven, a hot plate, infrared irradiation, electromagnetic wave irradiation, and the like. Further, examples of the ventilation heating drying method include a ventilation drying oven.

The dry film thickness (thickness of the cured product) of the polymerizable composition is appropriately set depending on the application, but is preferably from 0.05 to 300 μm, more preferably from 0.1 to 100 μm. .

<Pattern formation method>
When the polymerizable composition contains the alkali-soluble resin, a pattern can be formed by photolithography. The polymerizable composition is applied to the substrate in the same manner as described above, and if necessary, dried to form a dry film. Then, by irradiating the dried film with active energy rays through a mask, the radically polymerizable compound polymerizes in the exposed area, resulting in a cured film. On the other hand, a highly accurate pattern shape can also be created by direct writing using a laser without using a mask.

After the above exposure, the unexposed areas are developed and removed using an alkaline developer such as a 0.3 to 3% by mass aqueous sodium carbonate solution to obtain a patterned cured film. Further, post-drying is performed by post-baking at 180 to 250° C. for 20 to 90 minutes in order to improve the adhesion between the cured film and the base material. In this way, a desired pattern based on the cured film is formed.

The polymerizable composition of the present invention is a hard coating agent, a coating agent for optical discs, a coating agent for optical fibers, a coating agent for mobile terminals, a coating for home appliances, a coating for cosmetic containers, an internal antireflection coating for optical elements, and a high/low refractive index coating. Paints and coating agents such as coating agents, thermal barrier coating agents, heat dissipation coating agents, antifogging agents; offset printing inks, gravure printing inks, screen printing inks, inkjet printing inks, conductive inks, insulating inks, inks for light guide plates Printing inks such as; photosensitive printing plates; nanoimprint materials; resins for 3D printers; holographic recording materials; dental materials; materials for waveguides; black stripes for lens sheets; green sheets and electrode materials for capacitors; adhesives for FPD; Adhesives and sealants for HDDs, optical pickups, image sensors, organic EL sealants, OCA for touch panels, OCR for touch panels, etc. Color resists, black resists, protective films for color filters, FPD resists such as photo spacers, black column spacers, picture frame resists, photo resists for TFT wiring, and interlayer insulating films; resists for printed circuit boards such as liquid solder resists and dry film resists; semiconductor materials such as semiconductor resists and buffer coat films. It can be used for various purposes such as, and there are no particular restrictions on its uses.

The present invention will be explained in more detail with reference to Examples below.

１００ｍＬの四つ口フラスコ中に０．０４ｍｏｌのジフェニルチオエーテル、０．０４ｍｏｌのＡｌＣｌ_３、１０ｍＬのジクロロエタンを投入して、攪拌し、氷バスで冷却して温度が０℃までに低下した時に、０．０４ｍｏｌのプロピオニルクロライドと１５ｍＬのジクロロエタンの混合溶液を、温度を０℃以下に調整しながら、約２０分をかけて添加した。温度を０℃に保ち、引き続き２時間攪拌した。その後、０℃の１０％塩酸水中に反応液を徐々に投入し、分液漏斗で下層を分液し、上層を５０ｍＬのジクロロエタンで抽出した後、抽出液と下層液とを合わせた。その後、５％炭酸水素ナトリウム水溶液で洗浄し、更にｐＨの値が中性を呈するまでに２００ｍＬ水で３回洗浄し、３ｇ無水硫酸マグネシウムで乾燥して水分を除去した後、回転蒸発によりジクロロエタンを蒸発させた。蒸発が終わった後、回転蒸発瓶中の粗製品を酢酸エチルとヘキサンで精製し、化合物１－ａ（収量：８．３ｇ、ＬＣ純度：９２．６％、収率：９８．３％）を得た。 <(1) Synthesis of bisoxime ester photopolymerization initiator>
[Synthesis Example 1-a (Synthesis of Intermediate I (Compound 1-a))]

0.04 mol of diphenylthioether, 0.04 mol of AlCl ₃ and 10 mL of dichloroethane were put into a 100 mL four-necked flask, stirred, and cooled in an ice bath until the temperature dropped to 0°C. A mixed solution of .04 mol of propionyl chloride and 15 mL of dichloroethane was added over about 20 minutes while adjusting the temperature to below 0°C. The temperature was maintained at 0° C. and stirring continued for 2 hours. Thereafter, the reaction solution was gradually poured into 10% hydrochloric acid solution at 0° C., the lower layer was separated using a separatory funnel, the upper layer was extracted with 50 mL of dichloroethane, and the extract and lower layer were combined. Thereafter, it was washed with a 5% aqueous sodium bicarbonate solution, and then washed three times with 200 mL of water until the pH value became neutral, and after drying with 3 g of anhydrous magnesium sulfate to remove water, dichloroethane was removed by rotary evaporation. Evaporated. After the evaporation was completed, the crude product in the rotary evaporator was purified with ethyl acetate and hexane to obtain compound 1-a (yield: 8.3 g, LC purity: 92.6%, yield: 98.3%). Obtained.

１００ｍＬの四つ口フラスコ中に０．０２ｍｏｌの化合物１－ａ、０．０９ｍｏｌのＡｌＣｌ_３、５０ｍＬのジクロロエタンを投入して、攪拌し、氷バスで冷却して温度が０℃までに低下した時に、０．０４ｍｏｌの塩化ブチルと３０ｍＬのジクロロエタンの混合溶液を、温度を０℃以下に調整しながら、約２０分をかけて添加した。温度を０℃に保ち、引き続き２時間攪拌した。その後、０℃の１０％塩酸水中に反応液を徐々に投入し、分液漏斗で下層を分液し、上層を５０ｍＬのジクロロエタンで抽出した後、抽出液と下層液とを合わせた。その後、５％炭酸水素ナトリウム水溶液で洗浄し、更にｐＨの値が中性を呈するまでに２００ｍＬ水で３回洗浄し、３ｇ無水硫酸マグネシウムで乾燥して水分を除去した後、回転蒸発によりジクロロエタンを蒸発させた。蒸発が終わった後、回転蒸発瓶中の粗製品を酢酸エチルとヘキサンで精製し、化合物１－ｂ（収量：６．４ｇ、ＬＣ純度：９６．２％、収率：９５．８％）を得た。 [Synthesis Example 1-b (Synthesis of Intermediate II (Compound 1-b))]

0.02 mol of compound 1-a, 0.09 mol of AlCl ₃ and 50 mL of dichloroethane were put into a 100 mL four-necked flask, stirred, and cooled in an ice bath until the temperature dropped to 0°C. A mixed solution of 0.04 mol of butyl chloride and 30 mL of dichloroethane was added over about 20 minutes while adjusting the temperature to below 0°C. The temperature was maintained at 0° C. and stirring continued for 2 hours. Thereafter, the reaction solution was gradually poured into 10% hydrochloric acid solution at 0° C., the lower layer was separated using a separatory funnel, the upper layer was extracted with 50 mL of dichloroethane, and the extract and lower layer were combined. Thereafter, it was washed with a 5% aqueous sodium bicarbonate solution, and then washed three times with 200 mL of water until the pH value became neutral, and after drying with 3 g of anhydrous magnesium sulfate to remove water, dichloroethane was removed by rotary evaporation. Evaporated. After the evaporation was completed, the crude product in the rotary evaporator was purified with ethyl acetate and hexane to obtain compound 1-b (yield: 6.4 g, LC purity: 96.2%, yield: 95.8%). Obtained.

１００ｍＬのナスフラスコ中に０．０１２ｍｏｌの化合物１－ｂ、テトラヒドロフラン（ＴＨＦ）１２ｍＬ、濃塩酸０．５ｇ、亜硝酸イソアミル０．０３１ｍоｌを投入して、常温で５時間攪拌した後、反応液をビーカーに入れ、酢酸エチルと１０％食塩水で３回洗浄し、分液漏斗にて分層した。その後、５ｇ無水硫酸マグネシウムを加入して乾燥した後、吸引ろ過を行い、更に、ろ液を回転蒸発させた。蒸発が終わった後、回転蒸発瓶中の粗製品を酢酸エチルとヘキサンで精製し、化合物１－ｃ（収量：３．２ｇ、ＬＣ純度：８５．３％、収率：５８．４％）を得た。 [Synthesis Example 1-c (Synthesis of Intermediate III (Compound 1-c))]

0.012 mol of compound 1-b, 12 mL of tetrahydrofuran (THF), 0.5 g of concentrated hydrochloric acid, and 0.031 mol of isoamyl nitrite were put into a 100 mL eggplant flask, and after stirring at room temperature for 5 hours, the reaction solution was poured into a beaker. The mixture was washed three times with ethyl acetate and 10% saline, and the layers were separated using a separatory funnel. Thereafter, 5 g of anhydrous magnesium sulfate was added and dried, followed by suction filtration, and the filtrate was rotary evaporated. After the evaporation was completed, the crude product in the rotary evaporator was purified with ethyl acetate and hexane to obtain compound 1-c (yield: 3.2 g, LC purity: 85.3%, yield: 58.4%). Obtained.

１００ｍＬのナスフラスコ中に０．００９ｍоｌの化合物１－ｃ、テトラヒドロフラン（ＴＨＦ）１０ｍＬ、ピリジン（Ｐｙ）２ｇを投入して、攪拌し、アセチルクロリド０．０２９ｍоｌを、約０．５時間をかけて滴下した。引き続いて２時間攪拌した後、冷水５００ｍＬを滴下し始め、分液漏斗で分層した。その５％塩酸水で一回洗い、３％炭酸水素ナトリウム水溶液１０ｍＬで一回洗い、続いて１０％食塩水１０ｍＬで洗った後、１０ｇ無水硫酸マグネシウムで乾燥し、溶剤を回転蒸発させて、除去し、粘稠状液体を得た。該粘稠状液体に適量の酢酸エチルとヘキサンを加入し、ろ過、乾燥して、化合物１（収量：３．２ｇ、ＬＣ純度：９５．２％、収率：７７．３％）を得た。^１Ｈ－ＮＭＲによる分析結果を表１に示す。 [Synthesis example 1-d (synthesis of compound 1)]

0.009 mol of compound 1-c, 10 mL of tetrahydrofuran (THF), and 2 g of pyridine (Py) were put into a 100 mL eggplant flask, stirred, and 0.029 mol of acetyl chloride was added dropwise over about 0.5 hours. did. After continued stirring for 2 hours, 500 mL of cold water was added dropwise and the layers were separated using a separatory funnel. The solution was washed once with 5% hydrochloric acid, once with 10 mL of 3% sodium bicarbonate aqueous solution, and then with 10 mL of 10% saline, dried over 10 g of anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation. A viscous liquid was obtained. Appropriate amounts of ethyl acetate and hexane were added to the viscous liquid, filtered and dried to obtain Compound 1 (yield: 3.2 g, LC purity: 95.2%, yield: 77.3%). . The analysis results by ¹ H-NMR are shown in Table 1.

[Synthesis Example 10-b (Synthesis of Intermediate II (Compound 10-b))]
0.02 mol of compound 1-a, 0.09 mol of AlCl ₃ and 10 mL of dichloroethane were put into a 100 mL four-necked flask, stirred, and cooled in an ice bath until the temperature dropped to 0°C. A mixed solution of 0.02 mol of n-octanoyl chloride and 40 mL of dichloroethane was added over about 20 minutes while adjusting the temperature to below 0°C. The temperature was maintained at 0° C. and stirring continued for 2 hours. Thereafter, the reaction solution was gradually poured into 10% hydrochloric acid solution at 0° C., the lower layer was separated using a separatory funnel, the upper layer was extracted with 50 mL of dichloroethane, and the extract and lower layer were combined. Thereafter, it was washed with a 5% aqueous sodium bicarbonate solution, and then washed three times with 200 mL of water until the pH value became neutral, and after drying with 3 g of anhydrous magnesium sulfate to remove water, dichloroethane was removed by rotary evaporation. Evaporated. After the evaporation was completed, the crude product in the rotary evaporator was purified with ethyl acetate and hexane to obtain compound 10-b (yield: 7.5 g, LC purity: 96.0%, yield: 94.5%). Obtained.

[Synthesis Example 10-c (Synthesis of Intermediate III (Compound 10-c))]
0.008 mol of compound 10-b, 12 mL of tetrahydrofuran, 0.6 g of concentrated hydrochloric acid, and 0.020 mol of isoamyl nitrite were placed in a 100 mL eggplant flask, and after stirring at room temperature for 5 hours, the reaction solution was placed in a beaker. It was washed three times with ethyl acetate and 10% saline, and the layers were separated using a separatory funnel. Thereafter, 5 g of anhydrous magnesium sulfate was added and dried, followed by suction filtration, and the filtrate was rotary evaporated. After the evaporation was completed, the crude product in the rotary evaporator was purified with ethyl acetate and hexane to obtain compound 10-c (yield: 1.8 g, LC purity: 90.0%, yield: 48.0%). Obtained.

[Synthesis Example 10-d (Synthesis of Compound 10)]
0.003 mol of Compound 10-c, 5 mL of tetrahydrofuran, and 0.8 g of pyridine were placed in a 100 mL eggplant flask, stirred, and 0.010 mol of acetyl chloride was added dropwise over about 0.5 hours. After continued stirring for 2 hours, 500 mL of cold water was added dropwise and the layers were separated using a separatory funnel. After washing once with 5% hydrochloric acid solution, once with 10 mL of 3% sodium bicarbonate aqueous solution, and then with 10 mL of 10% saline solution, drying with 1 g of anhydrous magnesium sulfate, and removing the solvent by rotary evaporation. A crude product was obtained. Appropriate amounts of ethyl acetate and hexane were added to the crude product, filtered and dried to obtain Compound 10 (yield: 0.9 g, LC purity: 94.4%, yield: 52.6%). The analysis results by ¹ H-NMR are shown in Table 1.

[Synthesis Example 15-b (Synthesis of Intermediate II (Compound 15-b))]
0.02 mol of compound 1-a, 0.09 mol of AlCl ₃ and 45 mL of dichloroethane were put into a 100 mL four-necked flask, stirred, and cooled in an ice bath until the temperature dropped to 0°C. A mixed solution of 10 mL of 0.02 mol of isononanoyl chloride and 20 mL of dichloroethane was added over about 20 minutes while adjusting the temperature to 0° C. or lower. The temperature was maintained at 0° C. and stirring continued for 2 hours. Thereafter, the reaction solution was gradually poured into 10% hydrochloric acid solution at 0° C., the lower layer was separated using a separatory funnel, the upper layer was extracted with 50 mL of dichloroethane, and the extract and lower layer were combined. Thereafter, it was washed with a 5% aqueous sodium bicarbonate solution, and then washed three times with 200 mL of water until the pH value became neutral, and after drying with 3 g of anhydrous magnesium sulfate to remove water, dichloroethane was removed by rotary evaporation. Evaporated. After the evaporation was completed, the crude product in the rotary evaporator bottle was purified with ethyl acetate and hexane to obtain compound 15-b (yield: 2.6 g, LC purity: 95.6%, yield: 44.1%). Obtained.

[Synthesis Example 15-c (Synthesis of Intermediate III (Compound 15-c))]
0.01 mol of compound 15-b, 5 mL of tetrahydrofuran, 0.3 g of concentrated hydrochloric acid, and 0.004 mol of isoamyl nitrite were placed in a 100 mL eggplant flask, and after stirring at room temperature for 5 hours, the reaction solution was placed in a beaker. It was washed three times with ethyl acetate and 10% saline, and the layers were separated using a separatory funnel. Thereafter, 5 g of anhydrous magnesium sulfate was added and dried, followed by suction filtration, and the filtrate was rotary evaporated. After the evaporation was completed, the crude product in the rotary evaporator bottle was purified with ethyl acetate and hexane to obtain compound 15-c (yield: 0.6 g, LC purity: 94.9%, yield: 31.6%). Obtained.

[Synthesis Example 15-d (Synthesis of Compound 15)]
0.001 mol of Compound 15-c, 2 mL of tetrahydrofuran, and 0.3 g of pyridine were placed in a 100 mL eggplant flask, stirred, and 0.004 mol of acetyl chloride was added dropwise over about 0.5 hours. After continued stirring for 2 hours, 500 mL of cold water was added dropwise and the layers were separated using a separatory funnel. After washing once with 5% hydrochloric acid solution, once with 10 mL of 3% sodium bicarbonate aqueous solution, and then with 10 mL of 10% saline solution, drying with 1 g of anhydrous magnesium sulfate, and removing the solvent by rotary evaporation. A crude product was obtained. Appropriate amounts of ethyl acetate and hexane were added to the crude product, filtered and dried to obtain Compound 15 (yield: 0.6 g, LC purity: 96.9%, yield: 86.8%). The analysis results by ¹ H-NMR are shown in Table 1.

<(2) Evaluation of UV absorption characteristics>
For acetonitrile solutions of the compounds listed in Table 1, UV-VIS spectra at wavelengths from 200 to 600 nm were measured using a UV-VIS spectrum measuring device (1.0 cm quartz cell, manufactured by Shimadzu Corporation, UV-2450). The results are shown in Table 2.

Further, as comparative reference examples, the results of Compound R1, Compound R2, Compound R3, and Compound R4 are shown in Table 2.

In Table 2, λ _max is the maximum absorption wavelength (nm), ε _max is the molar extinction coefficient at the maximum absorption wavelength (L・mol ⁻¹・cm ⁻¹ ), and ε313 is the molar extinction coefficient at the wavelength of 313 nm (L・mol ^{− 1} ·cm ⁻¹ ), ε365 indicates the molar extinction coefficient (L·mol ⁻¹ ·cm ⁻¹ ) at a wavelength of 365 nm.

Generally, the larger the molar extinction coefficient of a photopolymerization initiator at the exposure wavelength, the more light is absorbed and the more likely radicals are generated. That is, for increasing the sensitivity of a photopolymerization initiator, a compound having a large molar absorption coefficient at the exposure wavelength is suitable. Ultra-high-pressure mercury lamps and high-pressure mercury lamps used for UV curing have a main wavelength of 365 nm (i-line) and efficiently emit light with a wavelength of 313 nm (j-line), etc. From the results in Table 2, it can be seen that the bisoxime ester photopolymerization initiator of the present invention has a large molar absorption coefficient at wavelengths of 365 nm and 313 nm emitted from a high-pressure mercury lamp or the like. Furthermore, although a single light having a wavelength of 365 nm or the like is emitted from the LED, it can be seen that Compound 1, Compound 10, and Compound 15 have large molar extinction coefficients at a wavelength of 365 nm.

<Examples 1 to 3, Comparative Examples 1 to 4>
<Preparation of polymerizable composition (A)>
The amounts of the radically polymerizable compound, alkali-soluble resin, and other components shown in Table 3 were mixed and stirred, and then a polymerization initiator was added and stirred thoroughly. Composition (A) was prepared.

In Table 3 above,
DPHA is a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (trade name: Aronix M-402, manufactured by Toagosei Co., Ltd.);
RD200 is a methyl methacrylate/methacrylic acid/cyclohexylmaleimide (mass%: 61/14/25) copolymer, weight average molecular weight: 17,000, acid value: 90 (synthetic product);
F-477 is a fluorine-based leveling agent (trade name: Megafac F-477, manufactured by DIC Corporation);
PGMEA represents propylene glycol monomethyl ether acetate (Fujifilm Wako Pure Chemicals Reagent);

<(3) Sensitivity evaluation>
The polymerizable composition (A) prepared above was applied onto an aluminum substrate using a spin coater. After coating, the solvent was dried by drying the aluminum substrate in a clean oven at 90° C. for 2.5 minutes to produce a uniform coating film with a thickness of 1.5 μm. Next, stepwise exposure was performed in a range of 10 mJ/cm ² through a mask pattern using a proximity exposure machine using an ultra-high pressure mercury lamp as a light source. The exposed aluminum substrate was immersed in a 1.0 mass % sodium carbonate aqueous solution at 23° C. for 60 seconds, and the unexposed areas were removed by development. Subsequently, washing was performed for 30 seconds with pure water to obtain a pattern shape. Table 5 shows the evaluation results for each polymerization initiator.
○: A film remains without dissolving.
×: Dissolved and no film remained.

<Preparation of polymerizable composition (B)>
The amounts of the radically polymerizable compound, alkali-soluble resin, and other components shown in Table 4 were mixed and stirred, and then a polymerization initiator was added and stirred thoroughly. Composition (B) was prepared.

In Table 4 above,
PE4A is pentaerythritol tetraacrylate (Tokyo Kasei Kogyo Reagent);
BYK302 is a silicone surface conditioner (manufactured by BYK Chemie Japan);
PGMEA represents propylene glycol monomethyl ether acetate (Fujifilm Wako Pure Chemicals Reagent);

<(4) Evaluation of color difference (b ^* value)>
The polymerizable composition (B) prepared above was applied onto a glass substrate using a spin coater. After coating, the glass substrate was dried in a clean oven at 90° C. for 2.5 minutes to dry the solvent, thereby producing a uniform coating film with a thickness of 1.5 μm. Then, using a conveyor-type UV irradiation device equipped with a high-pressure mercury lamp, irradiation was performed at 300 mJ/cm ² to prepare a test piece. As a result of measuring the degree of hardening of the obtained test pieces, the degree of hardening was 90% or more in all test pieces. Regarding the obtained test piece, the values of L ^* , a ^* , b ^* color system were measured by the transmission method according to JIS-Z-8722 using a spectrophotometer (CM-3500d, manufactured by Minolta Camera). . The value of b ^* is evaluated as an index of yellowness, and the smaller b ^* is, the lower the yellowness is. The results are shown in Table 5.
○: b ^* value is less than 1%.
△:b ^* value is 1% or more and less than 2%.
×:b ^* value is 2% or more.

<(5) Evaluation of solubility>
Each polymerization initiator shown in Table 2 was mixed with PGMEA, and the maximum concentration dissolved when stirring with a mix rotor at 25° C. was measured. Table 5 shows the solubility of each photoinitiator.
○: The maximum concentration dissolved in PGMEA is 20% or more.
×: The maximum concentration dissolved in PGMEA is less than 20%.

As shown in the table, the results of evaluations (3) to (5) indicate that the bisoxime ester photopolymerization initiator of the present invention has high sensitivity and high solubility, and suppresses coloration of the cured film. It is.

Claims (7)

General formula (I):

(R ¹ and R ² are independently linear or branched alkyl groups having 1 to 8 carbon atoms. R ¹ and R ² are not the same. R ³ is independently a straight chain or branched alkyl group having 1 to 8 carbon atoms. is a linear or branched alkyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms. The bisoxime ester photopolymerization initiator according to claim 1, wherein R ¹ or R ² is a methyl group. The bisoxime ester photopolymerization initiator according to claim 1 or 2, wherein R ³ is a methyl group. A polymerizable composition comprising a polymerization initiator including the bisoxime ester photopolymerization initiator according to any one of claims 1 to 3, and a radically polymerizable compound. The polymerizable composition according to claim 4, further comprising an alkali-soluble resin. A cured product formed from the polymerizable composition according to claim 4 or 5. 7. The method for producing a cured product according to claim 6, comprising the step of irradiating the polymerizable composition with active energy rays.