WO2007129605A1 - Method for producing (meth)acrylate and (meth)acrylate composition - Google Patents

Abstract

Disclosed is a simple method for producing a (meth)acrylate which enables to obtain a (meth)acrylate improved in storage stability and thermal stability. Also disclosed is a (meth)acrylate composition. The production method comprises an esterification step wherein a (meth)acrylic acid and an alcohol having an oxyalkylene group are dehydrated with an organic sulfonic acid catalyst in an organic solvent, thereby obtaining a (meth)acrylate; and an adjustment step wherein a compound A represented by the formula (1) below is controlled to be 0-100 ppm in the thus-obtained (meth)acrylate. The production method also comprises an addition step wherein a specific processing agent is added into an organic reaction liquid which contains not less than 1 ppm of the compound A relative to the (meth)acrylate obtained through the esterification step and a step for performing neutralization and water rinsing. (1) [In the formula (1), R1 represents an alkyl group or an aryl group; R2 represents an alkylene group; and R3 represents a hydrogen atom or a methyl group.]

Description

 Specification

 Method for producing (meth) acrylate and (meth) acrylate composition

 Technical field

 TECHNICAL FIELD [0001] The present invention relates to a method for producing (meth) acrylate and a (meth) acrylate composition.

 Background art

 [0002] (Meth) atalylate is cured by ultraviolet irradiation or electron beam irradiation, and as a compounding component of a photocurable composition, it is used in various industrial applications such as optical lenses, printing inks, coating agents, and adhesives. Used.

 [0003] However, if the storage stability and thermal stability of (meth) acrylate are poor, problems may occur.

 For example, if the storage stability of (meth) acrylate is poor, a polymerization reaction occurs during storage, resulting in a polymer component, or (meth) acrylate is decomposed and acid components such as (meth) acrylic acid are removed. May occur.

 The (meth) acrylate composition containing a polymer component causes uneven curing and turbidity, so it cannot be suitably used in applications such as optical lenses where uniformity and light transmission are important. In addition to the problems of odor and device corrosion, the (meth) atalylate generated deteriorates water resistance, so when used for coating agents and adhesives, the cured product absorbs moisture, causing the coating surface to peel off. Or the adhesive strength may be reduced. In addition, (meth) acrylates may be heated and stirred for homogenization at the time of blending, or may be exposed to a heat resistance test after photocuring, but (meth) acrylates with poor thermal stability are as described above. In addition to the generation of polymer components and acid components, coloring occurs, so it cannot be used in optical lens applications where transparency is essential.

 In this specification, acrylic acid and methacrylic acid are collectively referred to as “(meth) acrylic acid”.

[0004] One of the causes of poor storage stability and thermal stability of (meth) acrylate is the effect of impurities remaining in the product. (Meth) acrylate is usually produced by the dehydration reaction of (meth) acrylic acid and alcohols in the presence of an acid catalyst, but various impurities are by-produced during the ester reaction. In order to remove such impurities, the reaction solution after dehydration is usually washed with water or an aqueous alkaline solution, but the removal of impurities is not always sufficient.

 [0005] For this reason, various methods for strengthening the cleaning process during the production of (meth) acrylate are being studied.

 For example, Patent Document 1 discloses a method in which a reaction product after dehydration esterification is neutralized and then treated with amines! Speak.

 However, according to this method, after the reaction product is treated with the amine, the amine is removed from the reaction product, and therefore the reaction product must be washed with an acidic aqueous solution. Acidic components may be mixed into the product. Therefore, in this method, after washing with an aqueous alkaline solution after washing with an acidic aqueous solution, washing with soft water is repeated three times, and the process is complicated and requires a long time. Is remarkable. Also, if the treatment is carried out industrially, the ability to use a cleaning tank made of a special and expensive material that does not corrode both the alkaline aqueous solution and the acidic aqueous solution, the treatment with the alkaline aqueous solution and the treatment with the acidic aqueous solution Must be carried out in separate washing tanks and is not suitable for industrial implementation.

 [0006] Further, Patent Document 2 discloses a method of adding a cationic surfactant when neutralizing or washing the reaction solution after the production of (meth) acrylate. Therefore, it is disclosed that emulsification in the vicinity of the interface between the organic layer and the aqueous layer can be prevented, the separation time of the organic layer and the aqueous layer can be shortened, and as a result, impurities can be efficiently removed. It is.

 However, although the method described in Patent Document 2 is excellent in shortening the separation time between the organic layer and the aqueous layer, the storage stability and thermal stability of the obtained (meth) acrylate are insufficient. .

 [0007] Patent Document 1: Japanese Patent Laid-Open No. 6-219991

Patent Document 2: JP 2001-048831 A Disclosure of the invention

 Problems to be solved by the invention

 [0008] An object of the present invention is to provide a method for producing (meth) acrylate which can improve storage stability and thermal stability of the obtained (meth) acrylate by a simple method. A further object of the present invention is to provide a (meth) acrylate composition having improved storage stability and thermal stability.

 Means for solving the problem

[0009] The above-described problems of the present invention have been solved by the means described in <1>, <3>, and <9> below. The preferred embodiments are described below together with <2>, <4> to <8>, <10> and <11>.

 <1> An esterification process in which (meth) acrylic acid and an alcohol having an oxyalkylene group are dehydrated with an organic sulfonic acid catalyst in an organic solvent to form (meth) acrylate, and the obtained (meth) acrylate A process for producing (meth) acrylate, comprising a control step of controlling the compound A represented by the formula (1) in the formula so as to be Oppm or more and lOOppm or less,

 [0010] [Chemical 1]

[In the formula (1), R ¹ represents an alkyl group or an aryl group, R ² represents an alkylene group, and R ³ represents a hydrogen atom or a methyl group. ]

 <2> Management process capability The process for producing (meth) acrylate according to <1>, comprising at least one of the following 1) to 4).

 1) In the esterification step, (meth) acrylic acid is used in an amount of 0.8 mol to 2.0 mol with respect to 1 mol of alcohol hydroxyl group.

 2) Perform esterification reaction at 70 ° C or higher and 140 ° C or lower.

3) Finish when the esterification reaction is almost complete. 4) Compound A in the crude product obtained after neutralizing and washing the reaction solution obtained in the esterification process is heated in the presence of moisture to hydrolyze.

<3> Obtained by the esterification step (1) and step (1) by dehydrating (meth) acrylic acid and an alcohol having an oxyalkylene group with an organic sulfonic acid catalyst in an organic solvent to form (meth) acrylate. The organic reaction containing lppm or more of the compound A represented by the formula (1) with respect to the (meth) acrylate obtained in the step (2) and the step (2) in which the obtained reaction solution is neutralized and washed with water At least one selected from the group consisting of a quaternary ammonium salt, a quaternary phosphonium salt, an amidine, a compound having a primary amino group and a Z or secondary amino group, semicarbazide and pyridine. A method for producing (meta) atallylate, comprising an addition step of adding a specific treatment agent;

[Chemical 2]

[In the formula (1), R ¹ represents an alkyl group or an aryl group, R ² represents an alkylene group, and R ³ represents a hydrogen atom or a methyl group. ]

 <4> The method for producing a (meth) acrylate according to <3>, further comprising a desolvation step of distilling off the organic solvent after the addition step of adding the specific treating agent,

<5> After the step (2), including a desolvation step of distilling off the organic solvent, an addition step of adding the specific treating agent to the reaction solution after the desolvation step, and a heating step of heating <3> A process for producing the (meth) attalylate according to claim 1,

 <6> The method for producing a (meth) acrylate according to <5>, wherein the heating temperature is 30 to: LOO ° C.

 <7> Alcohol power having an oxyalkylene group <1> to 6> which is an alkylene oxide adduct of a polyhydric alcohol,

<8> The oxyalkylene group of the alcohol having an oxyalkylene group is 1) to <7> any one of (1) to <7>, wherein the alkylene group of R ² in the formula (1) is a ethylene group or a propylene group. Method,

 <9> A composition comprising (meth) acrylate having a (meth) acrylic acid and an (oxy) alkylene group obtained by subjecting an alcohol having an oxyalkylene group to a dehydrating ester reaction in the presence of an organic sulfonic acid catalyst. A (meth) acrylate composition containing O ppm or more and ΙΟΟρ pm or less of the compound A represented by the formula (1),

 [0013] [Chemical 3]

[In the formula (1), R ¹ represents an alkyl group or an aryl group, R ² represents an alkylene group, and R ³ represents a hydrogen atom or a methyl group. ]

[0014] <10> Alcohol power having an oxyalkylene group [9] The (meth) acrylate composition according to 9>, which is an alkylene oxide adduct of a polyhydric alcohol,

<11> old Kishianorekiren group Anorekonore having old Kishianorekiren group is the old Kishe styrene group or O alkoxy propylene group, an alkylene group of R ² in the formula (1) is a Echire down or propylene <9> or (Meth) ate acrylate composition according to 10>

 [0015] According to the present invention, it is possible to improve the storage stability and thermal stability of the (meth) atalylate obtained by a simple method, more specifically, it is possible to suppress an increase in acid value. It was possible to provide a method for producing (meth) atallylate. Furthermore, according to the present invention, it was possible to provide a (meth) acrylate composition that has improved storage stability and thermal stability, and more specifically can suppress an increase in acid value.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0016] The inventors of the present invention have provided a method for producing (meth) atarylate, in which the storage safety of (meth) atalylate is reduced. Various investigations were conducted on causative substances that cause poor qualitative and thermal stability.

 As a result, it has been found that when a specific compound is present in a specific amount in (meth) acrylate, the acid component increases with time, and by setting this value to a specific amount or less, the (meth) acrylate is reduced. The present inventors have found that storage stability and thermal stability can be improved and have completed the present invention.

 Furthermore, when the specific compound that is the causative substance exceeds a specific amount, it is possible to improve the storage stability and thermal stability of (meth) acrylate by treating with a specific treatment agent. The headline and the present invention were completed.

 Hereinafter, the present invention will be described in detail.

 [0017] The first (meth) acrylate production method of the present invention comprises dehydrating (meth) acrylic acid and an alcohol having an oxyalkylene group with an organic sulfonic acid catalyst in an organic solvent. The compound A represented by the following formula (1) in the resulting (meth) atallylate is Oppm or more and lOOppm or less (in the present invention, “Oppm or more and 10 Oppm or less”). It is also described as “0˜: LOOppm” or “Oppm˜: LOOppm” (hereinafter the same shall apply), and includes a management process for controlling so that it becomes the same.

 [0018] Further, the second method for producing (meth) acrylate according to the present invention includes dehydrating (meth) acrylic acid and alcohol having an oxyalkylene group with an organic sulfonic acid catalyst in an organic solvent. The reaction solution obtained in the esterification step (1), the step (1) is neutralized and washed with water (2), and the (meth) acrylate is obtained in step (2). In an organic reaction solution containing lppm or more of the compound A represented by the formula (1), a quaternary ammonium salt, a quaternary phosphonium salt, an amidine, a primary aamino group, and a Z or secondary amino group And a compound consisting of semicarbazide and pyridine, and an addition step of adding at least one selected specific treatment agent.

 [0019] (Compound A)

 Hereinafter, the compound A represented by the formula (1) will be described.

[0020] [Chemical 4]

In the formula (1), R ¹ represents an alkyl group or an aryl group, R ² represents an alkylene group, and R ³ represents a hydrogen atom or a methyl group.

R ¹ represents an alkyl group or an aryl group, and the alkyl group and aryl group may be unsubstituted or may have one or more substituents. The alkyl group preferably has 1 to 10 carbon atoms, and the aryl group preferably has 6 to 12 carbon atoms. The alkyl group may be linear or branched and may have a good cyclic structure.

 Examples of the substituent allowed for the alkyl group include an aryl group, an alkoxy group, and a halogen atom, preferably an aryl group, a chloro group, and a rhogen atom, more preferably an aryl group, and particularly preferably a phenyl group. is there.

 Further, examples of the substituent allowed for the aryl group include an alkyl group, a halogen atom, and an alkoxy group, preferably an alkyl group, and more preferably an alkyl group having 1 to 3 carbon atoms.

Specifically, preferred examples of R ¹ include a methyl group, a phenyl group, a tolyl group, an ethylphenol group, and a benzyl group.

[0023] In compound A, R ¹ is derived from the organic sulfonic acid catalyst used in the esterification reaction.

In the case where R ¹ is a methyl group, methanesulfonic acid is used as an acid catalyst. Similarly, in the case of a phenol group, benzenesulfonic acid is used, and in the case of a toluyl group, p-toluenesulfonic acid or ethylphenol is used. In the case of a-group, ethylbenzene sulfonic acid is used. In the case of a benzyl group, benzyl sulfonic acid is used.

The alkylene group for R ² is preferably an alkylene group having 4 or less carbon atoms, more preferably an ethylene group or a propylene group. R ² corresponds to the alkylene oxide group of the alcohol used in the esterification reaction.

R ³ represents a hydrogen atom or a methyl group. R ³ is the (meth) attaly used in the esterification reaction. Corresponds to formic acid.

 [0024] Compound A is presumed to be a reaction product of the alcohol used in the esterification reaction and the organic sulfonic acid catalyst. It is speculated that if compound A is present in (meth) acrylate, it decomposes over time and generates acid, which makes storage stability and thermal stability of (meth) acrylate become poor. .

[0025] Examples of the method for analyzing the content ratio of compound A in (meth) attalylate include liquid chromatography and gas chromatography, and liquid chromatography is preferable because compound A can be observed stably without decomposition. .

 Furthermore, as liquid chromatography, liquid chromatography / mass spectrometry (hereinafter referred to as LCZMS) is preferable because of its excellent quantitativeness and detection sensitivity.

[0026] The quantification conditions for Compound A by LCZMS include the following.

 OLC conditions

 Equipment: High performance liquid chromatograph (HPLC), column type: ODS column, column temperature: 40 ° C, eluent: water Z methanol system

 OMS conditions

 Detector: ESI (+)

[0027] (Manufacturing method of (meth) attalylate)

 In the present invention, first, an esterification step is performed in which (meth) acrylic acid and an alcohol having an oxyalkylene group are dehydrated with an organic sulfonic acid catalyst in an organic solvent to give (meth) acrylate. Hereinafter, the esterification process will be described.

[0028] 1. Esterification process

 In the present invention, first, (meth) acrylic acid and an alcohol having an oxyalkylene group (hereinafter sometimes simply referred to as “alcohol”) are dehydrated in an organic solvent in the presence of an organic sulfonic acid catalyst. (Meta) Atarirate. It is preferred that the dehydration reaction is carried out under heating and stirring.

[0029] The oxyalkylene group in the alcohol is preferably an oxyalkylene group having 4 or less carbon atoms, more preferably an oxyethylene group or an oxypropylene group.

As the oxyalkylene group in alcohol, a polyoxyethylene having two or more repeating units is used. It may be a gifted xylanolylene group!

[0030] Various compounds can be used as the alcohol, and specific examples thereof include the following alkylene oxide adducts of alcohol.

[1] Methanol, ethanol, n-propyl alcohol, isopropyl alcohol, _n -butinoreanoreconole, isobutinoleanoreconole, n-pentenoreanoleconole, cyclohexanol, n-heptyl alcohol, Monovalent alkyl alcohols such as n-octyl alcohol, 2-ethyl hexyl alcohol, isooctyl alcohol, n-nor alcohol, and isol alcohol, and calories with these alkylene oxides.

 [2] Phenol, black mouth phenol, bromophenol, fluorophenol, naphthol

Compounds having a phenolic hydroxyl group such as phenylphenol, tamphenol, nonylphenol, bisphenol A, bisphenol F, thiobisphenol and 4,4,1sulfoldiphenol, and alkylene oxide adducts thereof.

 [3] Glycols such as ethylene glycol, propylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, and their alkylene oxide adducts.

 [4] Glycerin such as glycerin, diglycerin, triglycerin, polyglycerin, and their alkylene oxide adducts.

 [5] Polyols such as butanediol, pentanediol, hexanediol, trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, and their alkylene oxide adducts.

 [6] Tris 2-hydroxyethyl isocyanurate.

 The alkylene oxide is preferably an alkylene oxide having 4 or less carbon atoms, more preferably ethylene oxide or propylene oxide.

 The average number of moles of alkylene oxide per mole of the compound is preferably 1 to 10 moles.

[0031] Among the alcohols described above, the present invention is likely to generate a large amount of impurities in the obtained (meth) acrylate, and an alkylene oxide adduct of a polyhydric alcohol or alkylene oxide. It can be more preferably applied to alcohol with a large number of id additions.

 Preference is given to alkylene oxide adducts of polyhydric alcohols, and specific examples thereof include alkylene oxide adducts of trimethylolpropane, bisphenol A alkylene oxide adducts and diglycerin alkylene oxide adducts. Specific examples of the alkylene oxide adduct include an ethylene oxide adduct and a propylene oxide adduct.

 Alcohols with a large number of alkylene oxide additions are alcohols having an alkylene oxide group with an average addition mole number of 3 moles or more per mole of the compound. Specific examples of the alkylene oxide adduct include ethylene oxide adduct and propylene oxide adduct.

 [0032] The proportion of (meth) acrylic acid and alcohol used in the dehydration esterification reaction is more preferably 0.8 to 2.0 moles of (meth) acrylic acid per mole of hydroxyl groups of the alcohol. 1. 0 to 1.5 moles. If the acrylic acid is used in an amount of 0.8 mol or more, an alcoholic hydroxyl group having a short dehydration esterification reaction time may be added to the (meth) acrylate group of the (meth) acrylate, for example, by Michael addition. This is preferable because good product purity can be obtained with less reaction. In addition, when the proportion of acrylic acid used is 2.0 mol or less, good product purity with little addition reaction such as Michael addition of (meth) acrylic acid to the (meth) atalyloyl group of (meth) acrylate. In addition, it is preferable to remove unreacted acrylic acid after dehydration esterification. /.

 [0033] The organic sulfonic acid catalyst used in the dehydration esterification reaction includes an organic sulfonic acid catalyst represented by the formula (2).

 [0034] [Chemical 5]

 Yes

R ¹ —— S—— OH ( ² )

 II

 Yes

[0035] formula (2), R ¹ is the same as R ¹ in Formula (1), and the preferred scopes are also same. Specific examples of the organic sulfonic acid catalyst include p-toluenesulfonic acid, methanesulfonic acid, benzenesulfonic acid, ethylbenzenesulfonic acid and benzylsulfonic acid, and the like can be used alone or in any combination of two or more. Can be used.

 [0036] The use ratio of the organic sulfonic acid catalyst is preferably 0.05 mol% to 10 mol%, more preferably 0.5 mol% to 5 mol, relative to the number of moles of the alcoholic hydroxyl group subjected to dehydration esterification. %. A use rate of the organic sulfonic acid catalyst of 0.5 mol% or more is preferable because a practical reaction rate can be obtained. Also, if it is 10 mol% or less, the product purity with few side reactions is high and the labor required for the removal of the catalyst and the decolorization operation of the product in the purification process with little coloration is preferred.

 [0037] In the present invention, as the organic solvent used in the esterification step, it is preferable to use an organic solvent having low solubility in water produced by the dehydration esterification reaction. The esterification process is preferably carried out while azeotropically distilling off water.

 Examples of organic solvents that can be suitably used in the esterification process include aromatic hydrocarbons such as toluene, benzene and xylene, aliphatic hydrocarbons such as hexane, cyclohexane and heptane, and methyl ethyl ketone and cyclohexane. And ketones such as xanone.

 In consideration of the solubility of the substrate, the organic solvent may be used alone or in combination of two or more.

 The proportion of the organic solvent is preferably 30 to 70% by weight in the reaction solution.

[0038] The esterification reaction temperature is preferably 70 to 140 ° C. A reaction temperature of 70 ° C or higher is preferable because a rapid reaction can be performed. Further, it is preferable that the temperature is 140 ° C. or lower because gelling is not further generated due to less by-product of impurities in the esterification step.

[0039] In the esterification reaction, it is preferable to use a polymerization inhibitor for the purpose of preventing polymerization of the (meth) atalyloyl group, and oxygen-containing gas may be introduced into the reaction solution.

Examples of the polymerization inhibitor include organic compounds such as hydroquinone, tert butyl hydroquinone, hydrated quinone monomethyl ether, 2, 6 g tert-butyl-4-methyl phenol, 2, 4, 6-tri-tert-butyl phenol, benzoquinone, phenothiazine and the like. Polymerization inhibitors, inorganic polymerization inhibitors such as copper chloride and copper sulfate, and dibutyldithiocarbami Examples thereof include organic salt polymerization inhibitors such as copper acid. The polymerization inhibitors may be used alone or in any combination of two or more. The ratio of the polymerization inhibitor is preferably 5 to 20, OOOwtppm in the reaction solution S, more preferably 25 to 3, OOOwtppm.

 Examples of the oxygen-containing gas include air, a mixed gas of oxygen and nitrogen, and a mixed gas of oxygen and helium.

 [0040] 2. Control process for controlling compound A in (meth) acrylate to be ΟΌΌΙΠ or more and ΙΟΟΌΌΙΠ or less.

 In the first method for producing (meth) acrylate, in the obtained (meth) acrylate, the process of controlling the compound 表 represented by the formula (1) so as to be Oppm or more and lOOppm or less. including.

 If the proportion of compound A in (meth) acrylate is more than lOOppm, the storage stability and thermal stability of the composition will be poor.

 The proportion of Compound A is preferably Oppm or more and 80ppm or less, more preferably 0 to 50ppm, and particularly preferably 0 to 30ppm, more preferably not detected (lppm or less).

In particular, when R ¹ contains an aromatic group, the compound A is preferably 0 to 80 ppm, more preferably 0 to 50 ppm, and further preferably 0 to 30 ppm. Further, when R ¹ does not contain an aromatic group, for example, when it is an unsubstituted alkyl group, the compound A is preferably 0 to 30 ppm, more preferably 0 to 10 ppm. More preferably, it is 0 to 5 ppm.

[0041] As a method of setting the ratio of Compound A in the finally obtained (meth) acrylate to lOOppm or less,

( _a ) a method for carrying out the esterification reaction under mild conditions;

 (b) A method for carrying out the purification step carried out after the esterification reaction in the method for producing (meth) attalylate

 Etc. can be illustrated.

( _a ) As a method for carrying out the esterification reaction under mild conditions, specifically, the following (a) — L) to (a-3) can be exemplified.

 (a— 1) Method that does not use excessive (meth) acrylic acid relative to alcohol

 The use of 0.8 to 2.0 moles of (meth) acrylic acid per mole of alcohol hydroxyl group is preferred, and the use of 1.0 to 1.5 moles is more preferred 1. It is more preferable to use 0 to 1.2 mol.

 (a-2) Do not perform esterich reaction at excessively high temperature! /, method

 The esterification reaction is preferably performed at 70 to 140 ° C, more preferably 80 to 130 ° C, and further preferably 90 to 120 ° C.

 (a-3) Method to terminate when esterification reaction is almost complete

 The fact that the esterification reaction is almost complete is a method of converting the unreacted (meth) acrylic acid contained in the reaction liquid from the charged (meth) acrylic acid by periodically measuring the acid value of the reaction liquid. Alternatively, it can be confirmed by detecting the amount of water distilled by the esterification reaction.

 In the esterification reaction, since the reaction is usually matured for several hours after the esterification reaction (post-heating), there is a possibility that compound A may be generated by the subsequent heating. Therefore, a method is preferred in which heating is not performed for a long time after completion of the esterification reaction. In this case, the heating time is preferably within 3 hours, more preferably within 1 hour.

 In the present invention, it is also preferable to appropriately combine (a-1) to (a-3). In the method for carrying out the purification step performed after the esterification reaction in the (b) (meth) acrylate production method, the purification step includes neutralization treatment and water washing treatment.

 Furthermore, even if the above method is used, the reaction solution obtained by the esterification step is neutralized for the purpose of reducing the proportion of Compound A in the case where the proportion of Compound A in (meth) atalylate exceeds lOOppm. A method of hydrolyzing the compound A in the crude product obtained after the treatment and the water washing treatment by heating in the presence of moisture can be exemplified.

The heating temperature in this case may be set as appropriate according to the ratio of compound A in (meth) atalylate, but the heating temperature is preferably 60 to 140 ° C and 60 to 120 ° C. More preferred is 60 to 100 ° C. The heating time is preferably 0.5 hours to 300 hours, more preferably 5 to 200 hours, and further preferably 20 to 150 hours. [0042] One or more of the above-mentioned methods (a) to (b) are adopted, and the ratio of compound A in the obtained (meth) atalylate is regularly monitored, and finally obtained. It is controlled so that the compound A in the (meth) acrylate is less than lOOppm.

 Among the above methods, which method to use and under what conditions is selected based on the type and amount of the (meth) acrylic acid, alcohol and sulfonic acid catalyst used, and the obtained (meta) What is necessary is just to select suitably according to the ratio of the compound A in attalylate, the use of a final product, etc.

 Among the methods described above, the method for carrying out the esterification reaction under mild conditions and the neutralized and washed (meth) acrylate are heated in the presence of moisture to hydrolyze compound A, and then The method of carrying out the esterification reaction under mild conditions is more preferred in that it can be carried out on a simple and industrial scale, where the method of neutralizing and washing again is preferred.

[0043] 3. Neutralization treatment and water washing treatment

 In addition to the neutralization treatment and washing treatment in the purification step employed in the first production method of the present invention, and the neutralization treatment performed on the reaction solution after the esterification step in the second production method of the present invention, Next, the water washing process will be described.

[0044] 3- 1. Neutralization treatment

 The neutralization treatment is performed for the purpose of removing acidic components such as unreacted (meth) acrylic acid and organic sulfonic acid catalyst in the reaction product solution, and is usually performed by bringing the reaction solution into contact with an alkaline aqueous solution.

 The neutralization treatment may be carried out according to a conventional method, for example, a method of adding an alkaline aqueous solution in which an alkali component is dissolved in the reaction solution, stirring and mixing, and the like.

[0045] Examples of the alkali component include alkali metal salts such as lithium hydroxide, sodium hydroxide and potassium hydroxide, and ammonia. As the alkali component, one kind may be used alone, or two or more kinds may be used in any combination. Of these, sodium hydroxide is preferred because of its excellent effect, low cost and easy availability. In this case, the amount of the alkali component is preferably at least 1 time in terms of molar ratio with respect to the acid component of the reaction solution, more preferably 1.1 to 2.0 times. When the molar ratio of the alkali component is 1 or more times the acid component of the reaction solution, the acid component is sufficiently neutralized. Is preferable.

 The concentration of the alkaline aqueous solution is preferably 1 to 25% by weight, more preferably 10 to 25% by weight. It is preferable that the concentration of the alkaline aqueous solution is 1% by weight or more because the amount of drainage after neutralization can be reduced. In addition, it is preferable that the concentration of the aqueous alkali solution is 25% by weight or less because (meth) acrylate does not polymerize! /.

 [0046] The stirring and mixing time when adding the alkaline aqueous solution may be appropriately set according to the amount of the reaction solution, the amount of the acid component contained therein, the purpose, and the like, but is preferably about 5 minutes to 120 minutes.

 [0047] 3-2. Washing treatment.

 In the present invention, the esterification reaction solution (reaction solution after the esterification step) or neutralization treatment solution (reaction solution that has been further neutralized after the esterification step) is washed with water. . The point at which the water washing treatment is performed can be appropriately selected according to the components used and the purpose.

 What is necessary is just to perform a washing process according to a conventional method. Specifically, a method of adding water or an inorganic aqueous solution to the esterification reaction solution obtained by the esterification reaction or the neutralization treatment solution, stirring and mixing, and the like can be mentioned.

 In the washing step, water is usually used. On the other hand, when separation from the organic layer is improved or a product with high purity is required, it is preferable to use an aqueous solution containing an inorganic salt. Specifically, an aqueous solution of ammonium sulfate and a salt are preferred. Ammonium salt aqueous solution such as aqueous ammonium solution, sodium salt aqueous solution such as sodium chloride, and acidic water such as hydrochloric acid aqueous solution.

 [0048] 3-3. Other

 In the neutralization treatment and Z or water washing treatment, heating can be performed as necessary.

 Examples of the heating temperature include 30 to 80 ° C. Examples of the heating time include 5 minutes to 5 hours.

 It is preferable to use distilled water as water used in the neutralization treatment and Z or washing treatment.

In the case of heating, polymerization is prohibited for the purpose of preventing the polymerization of the (meth) atalyloyl group. It is preferable to use a stopper, and oxygen-containing gas may be introduced into the reaction solution. Examples of the polymerization inhibitor include the same ones as described above, and the ratio thereof includes the same ratio as described above.

 Examples of the oxygen-containing gas include the same as described above.

 [0049] In the first method for producing (meth) acrylate, in the case where the neutralized water washing treatment liquid contains an organic solvent, a solvent removal step is performed.

 To explain the solvent removal process, the neutralization treatment solution or water washing treatment solution is transferred to the solvent removal tank, and the organic solvent in the organic layer after the water layer is separated by the neutralization treatment or water washing treatment is removed. It is done.

 The solvent removal treatment may be carried out according to a conventional method, for example, a method of removing the organic solvent by heating the solvent removal tank under reduced pressure.

 The depressurization degree of the solvent removal tank may be appropriately set according to the raw material to be used and the purpose, and is preferably 0.5 to 50 kPa. A method of gradually increasing the depressurization degree depending on the degree of removal of the organic solvent is preferable.

 The heating temperature may be appropriately set according to the obtained (meth) acrylate, the degree of pressure reduction, and the purpose, but is preferably 40 to 100, more preferably 60 to 80 ° C. In order to suppress thermal polymerization of (meth) atrelate, it is preferable to maintain the temperature at 80 ° C or lower.

 In the solvent removal step, it is preferable to supply oxygen or add a polymerization inhibitor in order to suppress thermal polymerization of (meth) acrylate. Examples of the polymerization inhibitor include the same ones as described above, and the ratio thereof includes the same ratio as described above.

[0050] If further product quality is required, further filtration can be performed after the solvent removal step.

 The filtration step may be performed according to a conventional method.

[0051] 4. Treatment agent addition process

The second (meth) acrylate preparation method of the present invention is represented by the above formula (1) with respect to the (meth) acrylate prepared by performing the esterification step, neutralization treatment, and water washing treatment. In an organic reaction liquid containing lppm or more of compound A, a quaternary ammonium salt, a quaternary sulfo salt, an amidine, a compound having a primary amino group and a Z or secondary amino group, semicarbazide and An addition step (treatment agent addition step) of adding at least one specific treatment agent selected from the group consisting of lysine (hereinafter, simply referred to as treatment agent);

 These treatment agents can be used alone or in combination of two or more. Hereinafter, each treatment agent will be described.

[0052] 4—1. 4th grade ammonium salt

 As the quaternary ammonium salt, various compounds can be used, and a compound represented by the following formula (3) (hereinafter referred to as compound 3) is preferable.

[0053] [Chemical 6]

[0054] [In the equation ^(3), Ri~R 3 represents an alkyl group, R ⁴ represents an alkyl group or a benzyl group, X- represents an inorganic anion. ]

[0055] In Ri to R ⁴ in the formula (3), the alkyl group may be linear or branched, but may be linear. Is preferred. An alkyl group having 8 or less carbon atoms is preferred.

 Examples of the inorganic anion in X— in the formula (3) include halide ions, hydroxide ions and hydrogen sulfate ions. Among these, as the halide ions for which halide ions and hydroxide ions are preferred, chlorine ions and bromine ions are more preferable.

 [0056] Specific examples of the compound 3 include the following examples (1) and (2).

(Examples of compounds in which DRi R ⁴ has an alkyl group

Tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium hydroxide, tetra-n-butylammonium chloride, tetra-n-butylammonium-bromide, tetra-n-butylammonium hydroxide, and tetrabutylammonium sulfate. Examples of [0057] (2) Ri~R ³ compounds R ⁴ an alkyl group having a benzyl group

 Benzyltrimethylammonium chloride, benzyltriethylammonium chloride, and benzyltri-n-butylammonium chloride.

[0058] 4— 2. Quaternary phosphonium salt

 As the quaternary phosphonium salt, various compounds can be used, and a compound represented by the following formula (4) (hereinafter referred to as compound 4) is preferable.

[0059] [Chemical 7]

[0060] [In the equation (4), Ri~R ³ represents an alkyl group, R ⁴ represents an alkyl group or a benzyl group, X- represents an inorganic anion. ]

[0061] In Ri to R ⁴ in the formula (4), the alkyl group may be linear or branched, but may be linear. Is preferred. An alkyl group having 8 or less carbon atoms is preferred.

 Examples of inorganic anions in X— in the formula (4) include halide ions, hydroxide ions and hydrogen sulfate ions. Among these, the chloride ion and the bromide ion power are more preferable as the halide ion preferred for the halide ion and the hydroxide ion.

 [0062] Specific examples of compound 4 include benzyl-tree n-butyl phospho-mum chloride and tetra-n-butyl phospho-mu-bromide.

[0063] 4- 3. Amidine

 As the amidine, various compounds can be used as long as they have an amidine skeleton. Specifically, 1,8-diazabicyclo (5.4.0) undecene-7 (diazabicyclo [5.4.0] undec-7-ene; DBU) and 1,5-diazabicyclo (4.3.0) nonene 5 (diazabicyclo [4.

3.0] non-5-ene; DBN) and the like.

[0064] 4-4. Compounds having primary aminoamino and Z or secondary amino As a compound having a primary amino group and a Z or secondary amino group (hereinafter referred to as an amine compound), a compound having a primary amino group (hereinafter referred to as a primary amine) or a compound having a secondary amino group Examples thereof include compounds (hereinafter referred to as secondary amines and 1 ヽ ぅ) and compounds having primary amino groups and secondary amino groups (hereinafter referred to as primary and secondary amines).

 Various compounds can be used as the amine compound, and examples include the following examples.

[0065] Examples of primary amines include methylamines such as methenoreamine, ethenoreamine, propylamine, butynoleamine, 2-ethylhexylamine and hexadecylamine; alkyldiamines such as 1,6-hexanediamine; Alkoxyalkylamines such as propylamine and 3- (2-ethylhexyloxy) propylamine; (Dialkylamino) alkylamines such as 3- (dimethylamino) propylamine, 3- (jetylamino) propylamine and 3- (dibutylamino) propylamine Hydroxyalkylamines such as hydroxyethylamine and hydroxypropylamine; N-methyl-3,3'-iminobis (propylamine) and other N-anolenoiminobis (anolequinoleamine); and Riruamin, and the like.

 Among these, a compound having an alkyl group may be a branched alkyl group.

 Of the above-mentioned compounds, (dialkylamino) alkylamine and N-alkyliminobis (alkylamine) have the effect of the present invention because they have a primary amino group that is a tertiary amino group.

[0066] As the secondary amine, various compounds can be used. Dialkylamines such as dimethylamine, jetylamine, dipropylamine, dibutylamine, and di-2-ethylhexylamine; di-2-ethoxypropylamine and di3- (2-ethylhexyl) ) Dialkoxyalkylamines such as propylamine; and diallylamine.

 Among these, a compound having an alkyl group may be a branched alkyl group.

[0067] Examples of primary and secondary amines include 3,3, -iminobis (propyl) amine and 6,6, monoiminobis (hexyl) amine, and 3- (methylamino) propylamine. And (alkylamino) alkylamines such as min.

 [0068] The amine compound of the present invention can be used in the form of an inorganic salt as required.

 Specific examples include hydrochlorides and sulfates of the aforementioned compounds.

 However, as the amine compound, a compound in a form that is not an inorganic salt is preferable because it is excellent in the effect of the present invention.

[0069] Of these, compounds having a boiling point of 200 ° C or higher are preferred because the treating agent is less likely to evaporate in the solvent removal step, and the boiling point at 0.5 kPa is 60 ° C. As mentioned above, the compound which is 300 degrees C or less is preferable.

 Specific examples include 6,6, -iminobis (hexyl) amine, 1,6-hexanediamine, hexadecylamine and the like.

[0070] 4— 5. Semicarbazide

 Semicarbazide is a compound having at least one semicarbazide group. The semicarbazide that can be used in the present invention is preferably a compound represented by the following formula (5).

[0071] [Chemical 8]

In the formula (5), R ¹ and R 1 represent a monovalent organic group, which may be the same or different. R ¹ and R ² are preferably a substituted or unsubstituted alkyl group or a phenyl group. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a stearyl group, a benzyl group, and a hydroxyethyl group. Of these, lower alkyl groups having 1 to 4 carbon atoms are more preferred! /.

In formula (5), R ³ and R ⁴ each independently represents a hydrogen atom or a monovalent organic group, and is preferably a hydrogen atom.

In formula (5), A represents a hydrogen atom or an n-valent organic group. A is preferably an n-valent organic group, more preferably a divalent or trivalent organic group. In the formula (5), n is an integer of 1 or more, and an integer of 1 3 is preferable, and 2 or 3 is more preferable! /.

 The n-valent organic group is not particularly limited, but is preferably an aliphatic group or an alicyclic group that is preferably a hydrogen atom, a carbon atom, a nitrogen atom, and a group composed of Z or oxygen nuclear power. It is more preferable.

 Semicarbazide can be used alone or in combination of two or more.

 As the semicarbazide, various compounds can be used, and examples thereof include compounds obtained by reaction of isocyanate compounds with N, N-disubstituted hydrazines.

 [0074] The isocyanate compound is preferably a diisocyanate compound, such as 1,4-tetramethylene diisocyanate, 1,5 pentamethylene diisocyanate, 1, 6 Hexamethylene diisocyanate, 2, 2, 4 (or 2, 4, 4) Trimethyl-1, 6 Hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, 1, 3— Aliphatic or cycloaliphatic diisocyanates such as bis (isocyanatomethyl) monocyclohexane, 4,4'-dicyclohexylmethane diisocyanate, xylylene diisocyanate and tetramethylxylene diisocyanate; 4,4'-diphenyl -Aromatic diisocyanates such as l-methane diisocyanate, 1,4-phenolic diisocyanate, 2,4 tolylene diisocyanate and naphthalene diisocyanate Examples. In addition, polyisocyanates derived from these diisocyanates; and monoisocyanates such as n-butyl isocyanate, n-xyl isocyanate, n-octyl isocyanate, and phenyl isocyanate.

 Of these isocyanate compounds, aliphatic or alicyclic diisocyanates and polyisocyanates derived therefrom are preferred. Two or more of these isocyanate compounds may be used in combination.

[0076] Examples of N, N disubstituted hydrazine include N, N dimethyl hydrazine, N, N jet hydrazine, N, N dipropyl hydrazine, N, N diisopropyl hydrazine, N, N-distearyl hydrazine, N-methyl- N-ethylhydrazine, N-methyl-N-propyl hydrazine, N-methylN benzylhydrazine, N, N di (j8-hydrochichechinole) hydrazine and the like. [0077] The reaction of the isocyanate compound and the N, N disubstituted hydrazine can be carried out with or without a solvent. When using a solvent, it is necessary to use a solvent inert to isocyanate.

 The reaction is preferably carried out at 20 to 150 ° C, more preferably 0 to 100 ° C. It is preferable to react the isocyanate with the N, N disubstituted hydrazine in an approximately equivalent amount.

[0078] Among these, R ¹ and R ² in the above formula (5) are lower alkyl groups having 1 to 4 carbon atoms in that they have an excellent acid value increase suppressing function and are easily available, and R ³ and A semicarbazide having a semicarbazide group in which R ⁴ is a hydrogen atom is preferred. Furthermore, due to these advantages, R ¹ and R ² in the above formula (5) are lower alkyl groups having 1 to 4 carbon atoms because the treating agent is difficult to evaporate in the solvent removal step described later. A compound having a semicarbazide group in which R ³ and R ⁴ are hydrogen atoms and having a molecular weight of 200 or more is more preferable.

 The compounds include 1,4-tetramethylene bis-N, N dimethyl semicarbazide, 1, 6 hexamethylene bis-N, N dimethyl semicarbazide, 1, 1, 1 ', 1, monotetramethyl 4, 4' ( Methylenedi-p-phenylene) disemicarbazide and the following compounds are preferred.

 [0079] [Chemical 9]

 [0080] 4-6. Pyridine compounds

As the pyridine compound, various compounds can be used as long as they have a pyridine ring. Specifically, pyridine, methylpyridine, ethylpyridine, propylpyridine, butylpyridine, 4- (1-butylpentyl) pyridin, dimethinorepyridine, trimethinorepyridine, and triethinorepyridine are preferred to be basic compounds. , Phenol-pyridine, aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine and the like. Among these, the pyridine compound is preferably an aminoviridine compound, more preferably 2-dimethylaminopyridine or 4-dimethylaminopyridine.

[0081] 4- 7. Preferred Specific Treatment Agent

 In the second method for producing (meth) atallylate of the present invention, a compound having a quaternary ammonium salt, a quaternary phosphate salt, an amidine, a primary amino group and Z or a secondary amino group, Group power consisting of semicarbazide and pyridine Use at least one selected specific treatment agent. Of these, quaternary ammonium salts, quaternary phosphonium salts, amidine and semicarbazide are preferred, and semicarbazides are more preferred. The use of semicarbazide is preferred because it can give the resulting (meth) atarylate an anti-coloring effect in addition to the effect of suppressing the increase in acid value.

[0082] 4-8. Method of adding treatment agent

 The timing of addition of the specific treatment agent is arbitrary as long as it is a reaction solution obtained after neutralization treatment and water washing treatment, specifically, when filtration is performed before and after the solvent removal step. Includes the final product before and after the filtration process, and even the final product.

 Among these, a method of adding a specific treating agent before the solvent removal step is preferable. This method is preferable because the solvent removal step and the specific treatment agent addition step can be performed in one step, and the addition step of the specific treatment agent can be omitted.

 Examples of the method for adding the treatment agent include a method of adding to (meth) acrylate with stirring and mixing.

 [0083] The addition ratio of the specific treatment agent is 2 to: LO, OOOwt ppm, more preferably 5 to 3, OOOwtppm, more preferably 50 to: L, OOOwtppm. The power S is more preferable. When this value is 2 wtppm or more, the effect of the specific treatment agent can be exhibited effectively. On the other hand, when it is 10, OOOwtppm or less, the composition has excellent solubility in (meth) acrylate and the composition When used as a product, it is preferable because it is excellent in compatibility with other components.

 [0084] In the addition of the treating agent, a force that can be performed even at room temperature can be heated as necessary.

Especially when polyhydric alcohol is used as alcohol, heating is preferred. Yes. This is because when the polyhydric alcohol is used as the alcohol, the (meth) acrylate obtained becomes a highly viscous product, and the treatment agent can be uniformly blended in a short time by heating.

 The heating temperature and the heating time may be appropriately set according to the (meth) acrylate and the purpose to be obtained, but the heating temperature is preferably 30 to 100 ° C, more preferably 30 to 80 ° C. The heating time is preferably 5 minutes to 5 hours, more preferably 30 minutes to 3 hours. In the case of heating, a polymerization inhibitor is used for the purpose of preventing the polymerization of the (meth) atalyloyl group. It is preferable that oxygen-containing gas may be introduced into the reaction solution. Examples of the polymerization inhibitor include the same ones as described above, and the ratio thereof includes the same ratio as described above.

 Examples of the oxygen-containing gas include the same as described above.

5.m mr ...

 In the case where the neutralized water washing treatment liquid contains an organic solvent, a solvent removal step is performed. At this time, the organic solvent may be the organic solvent used in the esterification step, or may be added in the subsequent neutralization treatment and Z or water washing treatment.

 The solvent removal process will be described. The neutralization treatment liquid or the water washing treatment liquid is transferred to the solvent removal tank, and the organic solvent in the organic layer after the aqueous layer is separated by the neutralization treatment or the water washing treatment is removed.

 The solvent removal treatment may be carried out according to a conventional method, for example, a method of removing the organic solvent by heating the solvent removal tank under reduced pressure.

 The depressurization degree of the solvent removal tank may be appropriately set according to the raw material to be used and the purpose.

Preferably, the pressure is 0.5 to 50 kPa, and a method of gradually increasing the degree of vacuum depending on the degree of removal of the organic solvent is preferable.

 The heating temperature may be appropriately set according to the obtained (meth) acrylate, the degree of pressure reduction, and the purpose, but is preferably 40 to 100, more preferably 60 to 80 ° C. In order to suppress thermal polymerization of (meth) atrelate, it is preferable to maintain the temperature at 80 ° C or lower.

In the solvent removal process, oxygen is supplied in order to suppress thermal polymerization of (meth) acrylate. It is preferable to add a polymerization inhibitor. Examples of the polymerization inhibitor include the same ones as described above, and the ratio thereof includes the same ratio as described above.

 [0086] If further product quality is required, further filtration can be performed after the solvent removal step.

 In the filtration step, it is preferable to perform pressure filtration in accordance with a conventional method.

 Examples of the pressure filtration method include a method in which the reaction liquid after solvent removal is put into a filter equipped with filter paper and filtration is performed while pressure is applied to the filter. In this case, the method of adding a filter aid to the reaction solution after the desolubilizer, the method of pre-coating the filter aid on the surface of the excess filter paper, and the method of using these in combination are preferred because the filtration efficiency can be improved. Examples of gases used for pressurization include nitrogen, oxygen-containing gas (5% oxygen, 95% nitrogen) and air.

[0087] 6. Composition

 The (meth) attalylate obtained by the production method of the present invention can improve the storage stability and thermal stability of the obtained (meth) atalylate. Therefore, the obtained (meth) acrylate can be suitably used for various industrial applications such as optical lenses, printing inks, coating agents, and adhesives as a component of the active energy ray-curable composition.

 [0088] The third invention of the present invention is a (meth) acrylate having an oxyalkylene group obtained by dehydrating esterification of an alcohol having (meth) acrylic acid and an oxyalkylene group in the presence of an acid catalyst. The present invention relates to a (meth) attalylate-based composition containing a rate and containing Compound A in an amount of Oppm to lOOppm.

 [0089] When the proportion of Compound A in the composition exceeds lOOppm, the storage stability and thermal stability of the composition become poor.

 The proportion of Compound A is preferably Oppm or more and 80ppm or less, more preferably 0 to 50 ppm, and most preferably 0 to 30 ppm is not detected.

[0090] The (meth) acrylate composition can be preferably used in an active energy ray-curable composition.

When used as an active energy ray-curable composition, a photopolymerization initiator, (Meth) acrylate (other than (meth) acrylate) other than (meth) acrylate can be blended. Hereinafter, specific examples of each component will be described.

 [0091] Other (meth) acrylates include a compound having one (meth) attaroyl group [hereinafter mono (meth) acrylate and! /, U] and a compound having two or more (meth) attaroyl groups. [Hereinafter, poly (meth) acrylate and! /, U] and the like.

 [0092] Examples of mono (meth) acrylates include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate and butyl (meth) acrylate. Hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 1,4 butanediol mono (meth) acrylate; isobornyl acrylate, etc. And alicyclic mono (meth) acrylate. In addition to these, tetrahydrofurfuryl (meth) acrylate, carbitol (meth) acrylate, (meth) taroloyl morpholine, maleimide (meth) acrylate and glycidyl (meth) acrylate are included.

 [0093] Examples of poly (meth) acrylates include (meth) acrylates having two (meth) attalyloyl groups such as pentaerythritol di (meth) acrylate monostearate, and pentaerythritol tri (meth). Examples thereof include (meth) acrylate having three (meth) attaroyl groups, such as attalylate and trimethylolpropane tri (meth) acrylate. In addition to these, (meth) acrylate with 4 or more (meth) attalyloyl groups such as dipentaerythritol hexa (meth) acrylate and di (trimethylolpropane) tetra (meth) acrylate can be used. It is.

 [0094] Also, oligomers such as urethane (meth) acrylate, polyester (meth) acrylate and epoxy (meth) acrylate can be used.

 [0095] When a visible light or ultraviolet curable composition is used, a photopolymerization initiator is added to the composition. In addition, when setting it as an electron beam curable composition, it is not necessary to mix | blend a photoinitiator.

[0096] Specific examples of the photopolymerization initiator include benzoin such as benzoin, benzoin methyl ether, and benzoin propyl ether; acetophenone, 2,2-dimethoxy-1-2-phen-lucatophenone, 2,2-diethoxy-1- Phenolacetophenone, 1, 1-dichloroa Cetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl 1- [4- (methylthio) phenol] — 2-morpholinopropane monoone and N, N-dimethylaminoacetophenone, etc. Anthraquinones such as methyl anthraquinone, 1-claw anthraquinone and 2 amyl anthraquinone; 2, 4 dimethylthioxanthone, 2, 4-jetyl thioxanthone, 2 thiaxanthone and 2, 4 diisopropyl thixanthone Ketals such as dimethyl ketal and benzyl dimethyl ketal; benzophenone, methylbenzophenone, 4,4'-diclonal benzophenone, 4, 4 'bisjetylaminobenzobenzoenone, Michler's ketone, and 4-benzoyl luo 4' methyldiphenyl Rusulfide And 2, 4, 6 trimethylbenzoyldiphosphine phosphine oxide.

 A photosensitizer can be used in combination with the photopolymerization initiator as necessary. Examples of the photosensitizer include N, N dimethylaminobenzoic acid ethyl ester, N, N dimethylaminobenzoic acid isoamyl ester, triethylamine, and triethanolamine.

[0097] In addition to the above-described components, an antifoaming agent, a leveling agent, an inorganic filler, an organic filler, a light stabilizer, an anti-oxidation agent, an ultraviolet absorber, and the like can be blended as necessary. . If necessary, a small amount of an antioxidant, a light stabilizer, an ultraviolet absorber, a polymerization inhibitor and the like may be added.

 Example

 Hereinafter, the present invention will be described more specifically by describing examples and comparative examples.

[0099] [Various analysis methods]

 〇 Acid value

 According to JIS K 0070-1992, the obtained talate was dissolved in ethanol, and titrated with a potassium hydroxide solution using phenolphthalein as an indicator. The acid value of the sample was calculated from the following formula.

 Acid value [mg—KOHZg] = N X T X f X 56. 11 / W

 N: Concentration of alcoholic potassium hydroxide solution [molZL]

 T: Titration of alcoholic potassium hydroxide solution [ml]

f: Potency of alcoholic potassium hydroxide solution W: Sample weight [g]

[0100] 〇 Forced deterioration test

 By putting 5g of the obtained talate in a 30ml glass container and allowing it to stand for several days in an air-cooled dark place, the water concentration contained in the talate was adjusted to 1,000-3, OOOwtppm.

 Thereafter, the glass container containing attalylate was sealed and heated in a heating block maintained at 80 ° C. for 72 hours. After cooling, the acid value was measured by the method described above.

[0101] 〇 Comparative example 1 1

 In a 1 L side necked four-necked flask equipped with a reflux tube, 350 g of bisphenol A ethylene oxide 4 mol adduct, 180 g of acrylic acid, 348 g of toluene, 20.9 g of normal toluenesulfonic acid monohydrate, hydroquinone 0. 52 g and 0.52 g of cupric chloride were added. Heat and stir at a reaction liquid temperature of 100 to 119 ° C while blowing oxygen-containing gas (oxygen 5% by volume, nitrogen 95% by volume, and so on), and remove the generated water from the system with a Dean-Stark tube for 9 hours. The dehydration reaction was performed.

 After that, the reaction solution is cooled to 40 ° C or lower, extracted and washed by adding toluene and water, neutralized by adding a 20 wt% aqueous solution of sodium hydroxide and sodium hydroxide, and further added with water. Then, extraction washing was performed.

 To the obtained organic layer, 0.2 g of hydroquinone monomethyl ether (hereinafter referred to as MQ!) Was added, and heated to 60-80 ° C under reduced pressure [665 Pa; 5 mmHg] while blowing oxygen-containing gas. Toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained.

[0102] As a result of analyzing the compound A using LCZMS under the following conditions for the obtained atarylate, in formula (1), R ¹ is a tolyl group, R ² is an ethylene group, R ^It was confirmed that 3 contained 382 ppm of a compound having a hydrogen atom (hereinafter referred to as Compound A1).

 The identity of compound A1 was confirmed by the retention time of the standard substance of compound A1 and the fragment pattern. Compound A1 was quantified based on the results of preparing a calibration curve for the standard substance of Compound A1.

[0103] (UPLC)

Equipment: Acquity UPLC system manufactured by Nippon Waters Column: ODS column; Acquity BEH 1.7 μτα C18 (column: inner diameter; 2. Imm X length; 50 mm)

 Column temperature: 40 ° C

 Eluent: Water Z Methanol = 70Z30 (Initial) → 65/35 (lOmin) → 50/50 (20min) → 0/100 (21-23min)

 Flow rate: 0.4 mL / min

 Detector: Photodiode array (PDA) (200—400nm)

 Sample concentration: 1% methanol solution

 Injection volume: 5; z L

 (MS)

 Equipment: Quattro premier API tandem quadrupole

 Detection: ESI positive ionization detection

 Capillary voltage: 3.5kV,

 MS: MRM (monitor ion: m / z 271> 99), extractor: 4.0V, RF Lens: 3.0V, desolvation gas: 800LZhr, cone voltage: 30V,

 Cone gas flow rate: 50LZhr

 Source temperature: 120 ° C, solvent removal temperature: 400 ° C, collision energy: 30V

[0104] The acid value of the obtained acrylate was measured. Furthermore, in order to evaluate storage stability and heat stability, a forced deterioration test was performed, and then the acid value was measured. Table 1 shows the results.

[0105] Example 1 1

 In Comparative Example 1-1, the charged amount of acrylic acid was changed from 180 g to 150 g, the reaction temperature of dehydrated ester was changed from 100 to 119 ° C to 100 to 117 ° C, and the reaction time was changed from 9 hours to 5 hours and 30 minutes. Except for the change, attalylate was produced in the same manner as in Comparative Example 1-1 and purified in the same manner.

 With respect to the obtained acrylate, Compound A1 was quantified in the same manner as in Comparative Example 11, and the acid value and the acid value after the forced deterioration test were measured. The results are shown in Table 1.

[0106] Example 1 2 In Example 1-1, the crude product obtained after the solvent removal step was placed in a 500 ml flask, heated and stirred at 80 ° C, and then added with water to adjust the water concentration to 4,000- 5, Adjusted to OOOppm. Thereafter, the flask was sealed, and heating and stirring were continued for 72 hours.

 Thereafter, the crude product was cooled to 40 ° C. or less, neutralized by adding toluene and a 20 wt% sodium hydroxide aqueous solution, and further subjected to extraction washing by adding water.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained.

 With respect to the obtained acrylate, Compound A1 was quantified in the same manner as in Comparative Example 11, and the acid value and the acid value after the forced deterioration test were measured. The results are shown in Table 1.

[0107] 〇 Comparative Example 1 2

 In a flask similar to Comparative Example 1-1, 350 g of ethylene oxide 1 mol adduct of p-amylphenol, 142 g of acrylic acid, 321 g of toluene, 16.5 g of paratoluenesulfonic acid monohydrate, 0.48 g of hydroquinone, and secondary chloride 0.48 g of copper was added. While blowing oxygen-containing gas, the mixture was heated and stirred at a reaction solution temperature of 100 to 119 ° C, and the generated water was removed from the system by a Dean-Stark tube, and a dehydrating esterification reaction was performed for 9 hours.

 After that, the reaction solution is cooled to 40 ° C or lower, extracted and washed by adding toluene and water, neutralized by adding a 20 wt% aqueous solution of sodium hydroxide and sodium hydroxide, and further added with water. Then, extraction washing was performed.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained.

[0108] With respect to the obtained atarylate, Compound A1 was quantified in the same manner as in Comparative Example 11, and the acid value and the acid value after the forced deterioration test were measured. The results are shown in Table 1.

[0109] Example 1 3

In Comparative Example 1-2, the crude product obtained after the solvent removal step was placed in a 500 ml flask, heated and stirred at 80 ° C, and then added with water to adjust the water concentration to 4,000- 5, Adjusted to OOOppm. Thereafter, the flask was sealed, and heating and stirring were continued for 72 hours. Thereafter, the crude product was cooled to 40 ° C. or less, neutralized by adding toluene and a 20 wt% sodium hydroxide aqueous solution, and further subjected to extraction washing by adding water.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained. With respect to the obtained acrylate, Compound A1 was quantified in the same manner as in Comparative Example 11, and the acid value and the acid value after the forced deterioration test were measured. The results are shown in Table 1.

[0110] ○ Comparative Example 1 3

 In a flask similar to that of Comparative Example 1-1, a 2.5 mol adduct of propylene oxide of nourphenol, 350 g of acrylic acid, 106 g of acrylic acid, 295 g of toluene, 12.3 g of normal toluenesulfonic acid monohydrate, 0.44 g of hydroquinone, and Cupric chloride 0.44 g was added. While blowing oxygen-containing gas, the mixture was heated and stirred at a reaction solution temperature of 100 to 119 ° C, and the generated water was removed from the system by a Dean-Stark tube, and a dehydrating esterification reaction was performed for 9 hours.

 After that, the reaction solution is cooled to 40 ° C or lower, extracted and washed by adding toluene and water, neutralized by adding a 20 wt% aqueous solution of sodium hydroxide and sodium hydroxide, and further added with water. Then, extraction washing was performed.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained.

[0111] With respect to the obtained atelate, Compound A was analyzed under the following conditions using LCZMS. As a result, it was confirmed that the compound (1) contained 288 ppm of a compound (hereinafter referred to as compound A2) in which R ¹ is a tolyl group, R ² is a propylene group, and R ³ is a hydrogen atom. The identity of Compound A2 was confirmed by the retention time of the standard substance of Compound A2 and the fragment pattern. Compound A2 was quantified based on the results of a calibration curve prepared for the standard substance of Compound A2.

[0112] (UPLC)

 Same as Comparative Example 1-1.

(MS) Same as Comparative Example 1 1 except for the following.

 MS: MRM (monitor ion: m / z 285> 113), extractor: 3.0V, RF Lens: 2.0V, solvent removal gas: 800LZhr, cone voltage: 30V, cone gas flow rate: 50LZhr, source temperature: 120 ° C, solvent removal temperature: 400 ° C, collision energy: 10V)

[0113] Example 1-4

 In Comparative Example 1-3, the crude product obtained after the solvent removal step was placed in a 500 ml flask, heated and stirred at 80 ° C, and then added with water to adjust the water concentration to 4,000- 5, Adjusted to OOOppm. Thereafter, the flask was sealed, and heating and stirring were continued for 72 hours.

 Thereafter, the crude product was cooled to 40 ° C. or less, neutralized by adding toluene and a 20 wt% sodium hydroxide aqueous solution, and further subjected to extraction washing by adding water.

 To the obtained organic layer, 0.3 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained. With respect to the obtained acrylate, Compound A2 was quantified in the same manner as in Comparative Example 1-3, and the acid value and the acid value after the forced deterioration test were measured. The results are shown in Table 1.

[0114] Example 1-5

 In a flask similar to Comparative Example 1-1, 350 g of bisphenol A ethylene oxide with 4 moles of carotenol, 180 g of acrylic acid, 341 g of toluene, 10.6 g of methanesulfonic acid, 0.51 g of hydroquinone and 0.51 g of cupric chloride Was introduced. While blowing oxygen-containing gas, the mixture was heated and stirred at a reaction solution temperature of 100 to 119 ° C, and the generated water was removed from the system with a Dean-Stark tube, and a dehydrating esterification reaction was performed for 9 hours.

 After that, the reaction solution is cooled to 40 ° C or lower, extracted and washed by adding toluene and water, neutralized by adding a 20 wt% aqueous solution of sodium hydroxide and sodium hydroxide, and further added with water. Then, extraction washing was performed.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

[0115] The obtained crude product was put into a 500 ml flask, heated and stirred at 80 ° C, and water was added to adjust the water concentration to 4,000 to 5, 5 ppm. Then seal the flask and heat and stir Continued for 72 hours.

 Thereafter, the crude product was cooled to 40 ° C. or less, neutralized by adding toluene and a 20 wt% sodium hydroxide aqueous solution, and further subjected to extraction washing by adding water.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained.

[0116] The obtained atelate was analyzed for Compound A under the following conditions using LCZMS. As a result, it was confirmed that the compound (23) contained 23 ppm of a compound in which R ¹ was a methyl group, R ² was an ethylene group, and R ³ was a hydrogen atom (hereinafter referred to as compound A3). . The identity of compound A1-3 was confirmed by the retention time and fragment pattern of the standard substance of compound A3. Compound A3 was quantified based on the results of preparing a calibration curve for the standard substance of compound A3.

 Quantified based on.

[0117] (UPLC)

 Same as Comparative Example 1 1 except for the following.

 Eluent: Water / methanol = 10/90 (Initial— 5min) → 0/100 (10-1 lmin) Sample concentration: 2% methanol solution

[0118] (MS)

 Same as Comparative Example 1 1 except for the following.

 Capillary voltage: 4.5kV

 MS: MRM (monitor ion: m / z 195> 99), extractor: 2. OV, RF Lens: 3.0V, solvent removal gas: 800LZhr, cone voltage: 20V, cone gas flow rate: 50LZhr, source temperature: 120 ° C, solvent removal temperature: 400 ° C, collision energy: 10V

[0119] Example 1-6

In a flask similar to Comparative Example 1-1, 350 g of trimethylolpropane propylene oxide 6-mol adduct, 227 g of acrylic acid, 372 g of toluene, 13.3 g of methanesulfonic acid, 0.56 g of quinone quinone and cupric chloride Added 0.5 g. While blowing oxygen-containing gas, heat and stir at a reaction liquid temperature of 100 to 120 ° C, and remove the generated water from the system with a Dean-Stark tube. A 9-hour dehydration reaction was performed while leaving.

 After that, the reaction solution is cooled to 40 ° C or lower, extracted and washed by adding toluene and water, neutralized by adding a 20 wt% aqueous solution of sodium hydroxide and sodium hydroxide, and further added with water. Then, extraction washing was performed.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

[0120] The obtained crude product was placed in a 500 ml flask, heated and stirred at 80 ° C, and then added with water to adjust the water concentration to 4,000-5, OOOppm. Thereafter, the flask was sealed, and heating and stirring were continued for 72 hours.

 Thereafter, the crude product was cooled to 40 ° C. or less, neutralized by adding toluene and a 20 wt% sodium hydroxide aqueous solution, and further subjected to extraction washing by adding water.

 To the obtained organic layer, 0.2 g of MQ was added, and heated to 60 to 80 ° C. under reduced pressure while blowing oxygen-containing gas, and toluene was distilled off.

 After filtration under pressure, the product, atelate, was obtained.

[0121] As a result of analyzing the compound A using LCZMS under the following conditions for the obtained atelate, in formula (1), R ¹ is a methyl group, R ² is a propylene group, R ³ compounds of the hydrogen atom (hereinafter, compound A4 and U) Ru it was confirmed to contain 7 ppm.

 The identity of compound A4 was confirmed by the retention time of the standard substance of compound A4 and the fragment pattern. Compound A4 was quantified based on the results of preparing a calibration curve for the standard substance of Compound A4.

[0122] (UPLC)

 Same as Comparative Example 1 1 except for the following.

 Eluent: Water Z Methanol = 10/90 (Initial— 5min) → 0/100 (10-1 lmin) Sample concentration: 2% methanol solution

[0123] (MS)

 Same as Comparative Example 1 1 except for the following.

 Capillary voltage: 4.5kV

MS: MRM (monitor ion: m / z 209> 113), extractor: 2.0V, RF Lens: 3. 0V, solvent removal gas: 800LZhr, cone voltage: 20V, cone gas flow rate: 50LZhr, source temperature: 120 ° C, solvent removal temperature: 400 ° C, collision energy: 10V

[0124] [Table 1]

 [0125] 〇 Comparative Example 2-1

 In a 1-L side-mounted four-necked flask equipped with a reflux tube, 350 g of bisphenol A ethylene oxide 4 mol adduct, 150 g of acrylic acid, 348 g of toluene, and noratoluenesulfonic acid monohydrate (hereinafter referred to as PTS) 20. 9 g, 0.52 g of hydroquinone (hereinafter referred to as HQ) and 0.52 g of cupric chloride were added. Heat and stir at a reaction liquid temperature of 100 to 118 ° C while blowing oxygen-containing gas (oxygen 5% by volume, nitrogen 95% by volume, and so on), and remove the generated water from the system with a Dean-Stark tube for 7 hours. The dehydration esterification reaction of was carried out.

 After that, the reaction solution is cooled to 40 ° C or lower, extracted and washed by adding toluene and water, neutralized by adding a 20 wt% aqueous solution of sodium hydroxide and sodium hydroxide, and further added with water. Then, extraction washing was performed.

 To the obtained organic layer, 0.2 g of hydroquinone monomethyl ether (hereinafter referred to as MQ and!) Was added and heated to 60-80 ° C under reduced pressure while blowing oxygen-containing gas to distill off toluene. It was.

 After filtration under pressure, the product, atelate, was obtained.

[0126] With respect to the obtained atarylate, Compound A1 was quantified in the same manner as in Comparative Example 11, and the acid value and the acid value after the forced deterioration test were measured. Table 2 shows the results.

[0127] [Table 2] Compound A Acid value (mg- KOH / g)

 Type (wtppm) Immediately after production After forced deterioration Comparative example 2-1 A1 382 0.049 1.774

[0128] Example 2— 1

 Comparative Example 2-1 Esterification, neutralization, and extraction washing were performed in the same manner and conditions as in o

 To the obtained organic layer, 0.2 g of MQ and tetraptylammonium bromide as a treatment agent were added to 348 wtppm with respect to attalylate, stirred, and heated to 60-80 ° C under reduced pressure while blowing oxygen-containing gas. And toluene was distilled off.

 The reaction solution after removal of the solvent was filtered under pressure to obtain acrylate.

 The acid value immediately after manufacture and after the forced deterioration test was measured for the obtained atelate. Table 3 shows the results.

[0129] 〇Example 2-2 to 2-8

 In Example 2-1, attalylate was produced in the same manner as in Example 2-1, except that a predetermined amount of the treating agent described in Table 3 below was added in the solvent removal step.

 The reaction solution after removal of the solvent was filtered under pressure to obtain acrylate.

 The acid value immediately after manufacture and after the forced deterioration test was measured for the obtained atelate. Table 3 shows the results.

[0130] [Table 3]

 The abbreviations in Table 3 mean the following.

TBAB: Tetraptylammo-umbromide • TBAOH: Tetraptyl ammonium hydroxide

 TMAOH: Tetramethylammonium hydroxide

 • TBPB: Tetrabutylphosphonium bromide

 • IBHA: 6, 6, Iminobis (hexyl) amamine

 • DMAP: 4-Dimethylaminopyridine

 • HMSC: 1,6-hexamethylenebis-N, N-dimethylsemicarbazide

[0132] Example 2-9 to 2-11

 In Example 2-1, the solvent removal treatment without adding the treatment agent was performed. A predetermined amount of the treating agent described in Table 4 below was added to the crude product obtained after the toluene was distilled off, and the mixture was stirred at 70 ° C. for 1 hour for uniform mixing. Then, after filtration under pressure, a phthalate was obtained.

 The acid value immediately after manufacture and after the forced deterioration test was measured for the obtained atelate. Table 4 shows the results.

[0133] [Table 4]

 [0134] The abbreviations in Table 4 mean the following.

 DBA: Dibutylamine

 BA: Butyramine

 • DEA · HC1: Jetylamine hydrochloride

[0135] Example 2—12

 According to Examples 2-1 to 2-8, the solvent removal treatment without adding the treatment agent was performed.

The treating agent was added to the crude product obtained after distilling off toluene at the same rate as in Examples 2-1 to 2-8, and stirred at 70 ° C. for 1 hour for uniform mixing. Then, after filtration under pressure, attalylate was obtained. The obtained attalylate had a low acid value after the forced deterioration test as in Examples 2-1 to 2-8.

[0136] 〇 Comparative Example 2-2

 Comparative Example 2-1 Into the same flask as in Example 1, 372 g of trimethylolpropane propylene oxide 6-mol adduct, 200 g of acrylic acid, 294 g of toluene, PTS19. Og, HQO. 89 g and cupric chloride 0.89 g were added. While stirring the oxygen-containing gas, the mixture was heated and stirred within the reaction liquid temperature range of 80 to 110 ° C and the reaction system pressure range of 400 to 650 mmHg. The generated water was removed from the system with a Dean-Stark tube, and a 7-hour dehydrating esterification reaction was performed.

 After the completion of the reaction, the reaction solution was neutralized by the same method as in Comparative Example 2-1, further added with water, extracted and washed, and then the solvent was removed.

[0137] With respect to the obtained atarylate, Compound A2 was quantified in the same manner as in Comparative Example 1-3, and the acid value and the acid value after forced degradation test were measured. The results are shown in Table 5.

[0138] [Table 5]

 [0139] Example 2-13

 Esterification, neutralization treatment and extraction washing were performed in the same method and conditions as in Comparative Example 2-2 o

 To the obtained organic layer, 0.2 g of MQ and tetraptylammonium hydroxide as a treatment agent were added at 570 wtppm with respect to attalylate, added, and 60-80 ° C under reduced pressure while blowing oxygen-containing gas. The toluene was distilled off.

 The reaction solution after removal of the solvent was filtered under pressure to obtain acrylate.

 The acid value was measured for the obtained attalylate, and the acid value was measured after the forced deterioration test. Table 6 shows the results.

[0140] Example 2-14 to 2-18

In Example 2-13, attalylate was produced in the same manner as in Example 2-13, except that a predetermined amount of the treatment agent shown in Table 6 below was added in the solvent removal step. The reaction solution after removal of the solvent was filtered under pressure to obtain acrylate.

 The acid value immediately after manufacture and after the forced deterioration test was measured for the obtained atelate. Table 6 shows the results.

 [Table 6]

 [0142] Example 2—19

 In Examples 2 to 13, the solvent removal treatment without adding the treatment agent was performed. A predetermined amount of the treatment agent shown in Table 7 below was added to the crude product obtained after the toluene was distilled off, and the mixture was stirred at 70 ° C for 1 hour to be uniformly mixed. Then, after filtration under pressure, a phthalate was obtained.

 The acid value immediately after manufacture and after the forced deterioration test was measured for the obtained atelate. Table 7 shows the results.

[0143] [Table 7]

 [0144] Example 2-20

 In Examples 2-13 to 2-18, the solvent removal treatment without adding the treatment agent was performed.

 The treating agent was added to the crude product obtained after distilling off toluene at the same ratio as in Examples 2-13 to 2-18, and stirred at 70 ° C. for 1 hour to be uniformly mixed. Then, after filtration under pressure, attalylate was obtained.

The obtained attalylate had a low acid value after the forced deterioration test, as in Examples 2-13 to 2-18. Industrial applicability

 The production method of the present invention can be used for a production method of (meth) acrylate.

 Further, the obtained (meth) acrylate can be suitably used for various industrial uses such as optical lenses, printing inks, coating agents, and adhesives as a component of the photocurable composition.

Claims

Claims (meth) acrylic acid and an alcohol having an oxyalkylene group are dehydrated with an organic sulfonic acid catalyst in an organic solvent to give (meth) acrylate, and obtained in the esterification step. A method for producing (meth) acrylate, comprising a control step of controlling the compound A represented by the formula (1) in the obtained (meth) acrylate to be Oppm or more and lOOppm or less.

 [Chemical 1]

[In the formula (1), R ¹ represents an alkyl group or an aryl group, R ² represents an alkylene group, and R ³ represents a hydrogen atom or a methyl group. ]

[2] The method for producing a (meth) acrylate according to claim 1, wherein the management step includes at least one of the following 1) to 4).

 1) In the esterification step, (meth) acrylic acid is used in an amount of 0.8 mol to 2.0 mol with respect to 1 mol of alcohol hydroxyl group.

 2) Perform esterification reaction at 70 ° C or higher and 140 ° C or lower.

 3) Finish when the esterification reaction is almost complete.

 4) Compound A in the crude product obtained after neutralization and water washing treatment of the reaction solution obtained in the esterification process is heated in the presence of moisture to hydrolyze.

[3] According to steps (1) and (1), (meth) acrylic acid and alcohol having an oxyalkylene group are dehydrated with an organic sulfonic acid catalyst in an organic solvent to form (meth) acrylate. The obtained reaction solution is neutralized and washed with water (2), and contains (ppm) or more of compound A represented by formula (1) with respect to the (meth) acrylate obtained in step (2). In the reaction solution, at least one selected from the group consisting of a quaternary ammonium salt, a quaternary phosphonium salt, an amidine, a compound having a primary amino group and a Z or secondary amino group, semicarbazide and pyridine Including an addition step of adding a specific treatment agent; Do

 A method for producing (meth) atallylate.

 [Chemical 2]

[In the formula (1), R ¹ represents an alkyl group or an aryl group, R ² represents an alkylene group, and R ³ represents a hydrogen atom or a methyl group. ]

[4] The method for producing (meth) acrylate according to [3], further comprising a desolvation step of distilling off the organic solvent after the addition step of adding the specific treating agent.

[5] After the step (2), a desolvation step of distilling off the organic solvent,

 It includes an addition step of adding the specific treatment agent to the reaction solution after the desolvation step, and a heating step of heating.

 4. The method for producing a (meth) acrylate according to claim 3.

[6] The method for producing (meth) acrylate according to claim 5, wherein the heating temperature is 30 to 100 ° C.

[7] The method for producing (meth) acrylate according to any one of claims 1 to 6, wherein the alcohol having an oxyalkylene group is an alkylene oxide addition product of a polyhydric alcohol.

[8] Okishiarukiren Okishiarukiren group of the alcohol having a group is Okishiechiren group or O alkoxy propylene group, an alkylene group of R ² in the formula (1) is, according to claim 1 ethylene group or a propylene group 7. The method for producing (meth) atallylate according to any one of 7 above.

 [9] A composition comprising (meth) acrylate having an oxyalkylene group obtained by reacting (meth) acrylic acid and an alcohol having an oxyalkylene group in the presence of an organic sulfonic acid catalyst and dehydrating ester reaction. A (meth) attalylate composition containing the compound A represented by the formula (1) in a range of Oppm to lOOppm.

[Chemical 3]

[In the formula (1), R ¹ represents an alkyl group or an aryl group, R ² represents an alkylene group,

R ³ represents a hydrogen atom or a methyl group. ]

10. The (meth) acrylate composition according to claim 9, wherein the alcohol having an oxyalkylene group is an alkylene oxide addition product of a polyhydric alcohol.

[11] Sai Kishianorekiren old Kishianorekiren group Anorekonore having group is an old Kishiechiren group or O alkoxy propylene group, an alkylene group of R ² in the formula (1) is, according to claim 9 or 10 ethylene group or a propylene group (Meth) atarylate composition described in 1.