High Purity 3,4-Epoxycyclohexylmethyl Methacrylate

Abstract

To provide a high-purity 3,4-epoxycyclohexylmethyl methacrylate that is useful as a starting material for functional materials, optical members and the like having excellent transparency and heat resistance.SOLUTION: An alicyclic epoxy compound product has a purity of 3,4-epoxycyclohexylmethyl methacrylate equal to or greater than 98.0 wt.%, and a total content of a compound represented by the specified formula (a) and a compound represented by the specified formula (b) equal to or less than 1.3 wt.%. Preferably, this alicyclic epoxy compound product has a Hazen color number equal to or less than 25.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to high-purity 3,4-epoxycyclohexylmethyl methacrylate, a curable composition containing the same, and a cured product thereof, a sealant, an adhesive, a coating agent, and an optical component. [Background technology]

[0002] 3,4-epoxycyclohexylmethyl methacrylate is a compound having two different curable groups, a cationic polymerizable epoxy group and a radically polymerizable methacryloyl group, and can produce a cured product having various physical properties and characteristics by curing. The cured product thus obtained can be used as a functional material, an optical component, etc. That is, 3,4-epoxycyclohexylmethyl methacrylate can be used, for example, as a coating agent (including paint), a sealant, an adhesive, a raw material for optical materials, etc. However, when producing 3,4-epoxycyclohexylmethyl methacrylate, there is a problem that the raw materials and products are easily polymerized in the reaction process and the desolvation process of the reaction crude liquid. In addition, there is a problem that industrially produced 3,4-epoxycyclohexylmethyl methacrylate has a high degree of coloration and is easily discolored over time.

[0003] Patent Document 1 describes that in the process of producing 3,4-epoxycyclohexylmethyl(meth)acrylate by epoxidizing cyclohexenylmethyl(meth)acrylate with an oxidizing agent, the polymerization inhibition effect is significantly increased when a specific polymerization inhibitor is used in combination with a molecular oxygen-containing gas as a polymerization inhibitor in the reaction step and the low boiling point removal and / or productization step.

[0004] Patent Document 2 discloses a method for producing 3,4-epoxycyclohexylmethyl(meth)acrylate, which comprises the steps of (a) washing a reaction crude liquid containing 3,4-epoxycyclohexylmethyl(meth)acrylate obtained by epoxidizing cyclohexenylmethyl(meth)acrylate with an organic peracid with water using a device having a short contact time, (b) neutralizing the crude liquid with alkali, (c) removing the low boiling point components at a heating temperature of 100°C or less under reduced pressure to obtain a liquid having a low boiling point component content of 3 to 50% by weight, and (d) removing the low boiling point components at a heating temperature of 100°C or less under reduced pressure that is half or less that of the step (c) to obtain a liquid having a low boiling point component content of less than 1% by weight. Note that in the examples of Patent Document 1, the removal of low boiling points in the steps (c) and (d) is carried out using a thin-film evaporator, and the conditions for the first stage of removal of low boiling points are a heating temperature of 60°C and a pressure of 150 mmHg, and the conditions for the second stage of removal of low boiling points are a heating temperature of 60°C and a pressure of 40 mmHg. This method is said to be able to reduce the loss of valuable materials during the purification process, as well as to reduce the polymer content in the product, resulting in a product with a purity of 94 to 97%.

[0005] Patent Document 3 discloses a method for purifying 3,4-epoxycyclohexylmethyl(meth)acrylate, in which an alkaline water washing step is added between steps (c) and (d) in the method of Patent Document 2. In the examples of Patent Document 3, the low boiling point removal treatments in steps (c) and (d) are carried out using a flash tube. The evaporation conditions in the first and second stages are the same as those in Patent Document 2. This method is said to be able to prevent discoloration of the product and also to effectively prevent discoloration of the product over time.

[0006] Patent Document 4 describes that in a process for continuously purifying a crude liquid containing epoxidized cyclohexenyl methyl methacrylate after washing by connecting two or more thin-film evaporators to remove the solvent, blocking of the inside of the piping due to polymers can be suppressed by blowing molecular oxygen into the bottom hold tank of each thin-film evaporator. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2-262574 [Patent Document 2] Japanese Patent Application Publication No. 6-25203 [Patent Document 3] Japanese Patent Application Publication No. 9-67308 [Patent Document 4] Japanese Patent Application Publication No. 8-245511 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the 3,4-epoxycyclohexylmethyl methacrylate obtained by the above-mentioned conventional method is not necessarily sufficient in terms of quality and characteristics for use as a raw material for modern highly functional materials, high-performance optical components, etc. More specifically, the cured product obtained by curing the 3,4-epoxycyclohexylmethyl methacrylate produced by the conventional method is poor in transparency and heat resistance.

[0009] Therefore, an object of the present invention is to provide high-purity 3,4-epoxycyclohexylmethyl methacrylate which is useful as a raw material for functional materials excellent in transparency and heat resistance, optical members, etc. Another object of the present invention is to provide a high-purity 3,4-epoxycyclohexylmethyl methacrylate having excellent curability. It is still another object of the present invention to provide a curable composition useful as a raw material for functional materials excellent in transparency and heat resistance, optical components, etc., a cured product thereof, a sealant, an adhesive, or a coating agent containing the curable composition, and an optical component comprising a component made of the cured product.

[0010] In this specification, the term "product" refers to something that is industrially manufactured and in a form that can be distributed in the market, and is not a chemical substance itself. In the sense that completely pure industrial products do not exist in reality, a "product" can be said to be a composition (a composition that contains the target substance as the main component, for example, nearly 100% by weight). [Means for solving the problem]

[0011] As a result of intensive research by the present inventors to achieve the above object, they have found that when a reaction crude liquid containing 3,4-epoxycyclohexylmethyl methacrylate obtained by epoxidizing 3-cyclohexenylmethyl methacrylate is subjected to low-boiling point distillation and high-boiling point distillation, 3,4-epoxycyclohexylmethyl methacrylate with an extremely low content of specific impurities, high purity, excellent hue, and excellent curability is obtained, and when the 3,4-epoxycyclohexylmethyl methacrylate thus obtained is cured, a cured product with excellent transparency and heat resistance is obtained. Based on these findings and through further research, the present invention has been completed.

[0012] That is, the present invention provides an alicyclic epoxy compound product in which the purity of 3,4-epoxycyclohexylmethyl methacrylate is 98.0% by weight or more, and the total content of the compound represented by the following formula (a) and the compound represented by the following formula (b) is 1.3% by weight or less. [ka]

[0013] In the alicyclic epoxy compound product, the total content of the compound represented by formula (a), the compound represented by formula (b), and the compound represented by the following formula (c) is preferably 1.6% by weight or less. [ka]

[0014] In addition, in the alicyclic epoxy compound product, the total content of the compound represented by the formula (a), the compound represented by the formula (b), the compound represented by the formula (c), and the compound represented by the following formula (d) is preferably 2.0% by weight or less. [ka]

[0015] The Hazen color scale of the alicyclic epoxy compound product is preferably 25 or less.

[0016] The present invention also provides a curable composition comprising the cycloaliphatic epoxy compound product.

[0017] The curable composition may further contain a curing agent and a curing accelerator.

[0018] The curable composition may further contain a curing catalyst.

[0019] The present invention further provides a cured product of the curable composition.

[0020] The present invention still further provides a sealant comprising the curable composition.

[0021] The present invention also provides an adhesive comprising the curable composition.

[0022] The present invention further provides a coating agent comprising the curable composition.

[0023] The present invention still further provides an optical member comprising a member made of the cured product. Effect of the Invention

[0024] The alicyclic epoxy compound product of the present invention contains 3,4-epoxycyclohexylmethyl methacrylate at high purity and has a low content of specific impurities, so that a cured product having excellent transparency and heat resistance can be obtained by curing a curable composition containing this alicyclic epoxy compound product. In addition, the curable composition containing this alicyclic epoxy compound product has a faster curing speed than conventional products. According to the production method of the present invention, an alicyclic epoxy compound product having the above-mentioned excellent properties can be industrially and efficiently produced. The cured product and optical component of the present invention are produced by curing the above-mentioned curable composition, and therefore have excellent transparency and heat resistance. Since the sealant, adhesive, and coating agent of the present invention contain a curable composition having the excellent properties described above, a cured product having excellent physical properties such as transparency and heat resistance can be obtained in a relatively short time. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic diagram (cross-sectional view) illustrating an example of an optical member (optical semiconductor device) of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] [Alicyclic epoxy compound products] The alicyclic epoxy compound product of the present invention, i.e., high-purity 3,4-epoxycyclohexylmethyl methacrylate, is 3,4-epoxycyclohexylmethyl methacrylate (= the following formula (i) [ka] The alicyclic epoxy compound product of the present invention contains 3,4-epoxycyclohexylmethyl methacrylate (a compound represented by the formula (I)) having a purity (or content) of 98.0% by weight or more. The purity (or content) of 3,4-epoxycyclohexylmethyl methacrylate is preferably 98.5% by weight or more, more preferably 99.0% by weight or more, and particularly preferably 99.5% by weight or more. In the alicyclic epoxy compound product of the present invention, the purity of 3,4-epoxycyclohexylmethyl methacrylate is 98.0% by weight or more, so that the curability of the curable composition containing the alicyclic epoxy compound product can be improved, and the physical properties, particularly the heat resistance, of the cured product of the curable composition can be improved.

[0027] In addition, the alicyclic epoxy compound product of the present invention has a total content of the compound represented by formula (a) and the compound represented by formula (b) of 1.3% by weight or less. The total content of the compound represented by formula (a) and the compound represented by formula (b) is preferably 1.1% by weight or less, more preferably 0.09% by weight or less, and particularly preferably 0.07% by weight or less. By making the total content of the compound represented by formula (a) and the compound represented by formula (b) 1.3% by weight or less in the alicyclic epoxy compound product of the present invention, the physical properties, particularly the transparency and heat resistance, of the cured product of the curable composition containing the alicyclic epoxy compound product can be improved.

[0028] In the alicyclic epoxy compound product of the present invention, the total content of the compound represented by formula (a), the compound represented by formula (b), and the compound represented by formula (c) is preferably 1.6% by weight or less, more preferably 1.4% by weight or less, even more preferably 1.0% by weight or less, and particularly preferably 0.5% by weight or less (e.g., 0.2% by weight or less). By setting the total content of the compound represented by formula (a), the compound represented by formula (b), and the compound represented by formula (c) within the above range, the physical properties, particularly the transparency and heat resistance, of the cured product of the curable composition containing the alicyclic epoxy compound product can be further improved.

[0029] In the alicyclic epoxy compound product of the present invention, the total content of the compound represented by formula (a), the compound represented by formula (b), the compound represented by formula (c), and the compound represented by formula (d) is preferably 2.0% by weight or less, more preferably 1.5% by weight or less, even more preferably 1.0% by weight or less, and particularly preferably 0.5% by weight or less (e.g., 0.2% by weight or less). By setting the total content of the compound represented by formula (a), the compound represented by formula (b), the compound represented by formula (c), and the compound represented by formula (d) within the above range, the physical properties, particularly the transparency and heat resistance, of the cured product of the curable composition containing the alicyclic epoxy compound product can be further improved.

[0030] The compound represented by formula (b) (=3-cyclohexenylmethyl methacrylate) is a raw material for 3,4-epoxycyclohexylmethyl methacrylate, and is the unreacted raw material mixed into the alicyclic epoxy compound product. The compound represented by formula (a) and the compound represented by formula (c) are impurities contained in the raw material, and are mixed into the alicyclic epoxy compound product. The compound represented by formula (d) is an impurity that is mainly by-produced in the reaction process (epoxidation process), and can also be produced when the reaction product is evaporated or distilled (solvent removal process, low boiling point removal process, high boiling point removal process). The compound represented by formula (d) is produced by further epoxidizing the double bond of the target compound represented by formula (i).

[0031] The compound represented by formula (a), the compound represented by formula (b) and the compound represented by formula (c) do not have a cationic polymerizable group, and the compound represented by formula (d) does not have a radical polymerizable group. Therefore, if these compounds are contained in a large amount in an alicyclic epoxy compound product, the desired physical properties (e.g., heat resistance, mechanical strength, etc.) may not be obtained for the cured product obtained by curing the alicyclic epoxy compound product. In addition, since the compound represented by formula (a) has an aromatic ring and the compound represented by formula (b) has an unsaturated bond, if these compounds are contained in a large amount in an alicyclic epoxy compound product, it will cause the color of the cured product to deteriorate.

[0032] Although the compounds represented by formula (a) and (c) have lower boiling points than the target compound [compound represented by formula (i)], the difference in boiling points is not so great, so they cannot be separated and removed by a low-boiling point removal treatment (solvent removal treatment) using an evaporator such as a thin-film evaporator described in the above patent document. On the other hand, the compounds represented by formula (d) have a higher boiling point than the target compound [compound represented by formula (i)], so they cannot be separated and removed by a low-boiling point removal treatment (solvent removal treatment) using an evaporator such as a thin-film evaporator described in the above patent document, and are mixed into the bottom product. In addition, if an epoxidizing agent such as an organic peroxy acid is used in excess of the raw material compound represented by formula (b) in the reaction process to reduce the remaining amount of the unreacted compound represented by formula (b), the by-product amount of the compound represented by formula (d) increases. Conversely, if the amount of an epoxidizing agent such as an organic peroxy acid is reduced in order to reduce the by-product amount of the compound represented by formula (d), the remaining amount of the unreacted compound represented by formula (b) increases. The above patent documents make no mention of the presence of these impurities and therefore make no disclosure or suggestion as to how such impurities might be removed.

[0033] In the alicyclic epoxy compound product of the present invention, the content of the compound represented by formula (a) is preferably 0.3% by weight or less, more preferably 0.2% by weight or less, even more preferably 0.1% by weight or less, and particularly preferably 0.05% by weight or less (e.g. 0.02% by weight or less). The content of the compound represented by formula (b) is preferably 1.0% by weight or less, more preferably 0.8% by weight or less, even more preferably 0.5% by weight or less, and particularly preferably 0.2% by weight or less (e.g. 0.1% by weight or less). The content of the compound represented by formula (c) is preferably 0.3% by weight or less, more preferably 0.2% by weight or less, even more preferably 0.1% by weight or less, and particularly preferably 0.05% by weight or less (e.g. 0.03% by weight or less). The content of the compound represented by formula (d) is preferably 0.6% by weight or less, more preferably 0.3% by weight or less, even more preferably 0.2% by weight or less, and particularly preferably 0.1% by weight or less (e.g. 0.05% by weight or less).

[0034] The alicyclic epoxy compound product of the present invention has a low coloration degree, and the Hazen color number (APHA) is, for example, 25 or less, preferably 20 or less, and particularly preferably 18 or less. In addition, the alicyclic epoxy compound product of the present invention also has excellent storage stability, and the increase rate of the Hazen color number (APHA) of the alicyclic epoxy compound product after storage at 30° C. for one month is less than 200%.

[0035] (Production method of alicyclic epoxy compound products) The alicyclic epoxy compound product of the present invention can be produced through the following steps. Note that either step B or step C may be carried out first. Step A: A step of epoxidizing 3-cyclohexenylmethyl methacrylate with an organic peracid to obtain a reaction product (reaction crude liquid) (epoxidation step) Step B: A step of subjecting the reaction product (which may have undergone a predetermined step) to low-boiling distillation (low-boiling step) Step C: A step of subjecting the reaction product (which may have undergone a predetermined step) to high-boiling distillation (high-boiling step)

[0036] After completion of step A, and before step B (step C when steps are performed in the order of step C-step B), a step of washing the obtained reaction product with water (water washing step) or a step of neutralizing the reaction product with an alkali (alkali neutralization treatment step) may be provided. When step B is performed in multiple steps, a step of washing with an aqueous alkali solution (alkali water washing step) may be provided between each step. Furthermore, a desolvation step may be provided before step B or step C in order to remove the solvent in the reaction product. This desolvation step corresponds to the low-boiling point removal step described in the above patent document.

[0037] (Epoxidation process) The epoxidation step is a step in which 3-cyclohexenylmethyl methacrylate represented by formula (b) is reacted with an organic peracid to produce 3,4-epoxycyclohexylmethyl methacrylate, as shown in the following formula. In this step, a reaction product (reaction crude liquid) containing 3,4-epoxycyclohexylmethyl methacrylate represented by formula (i) is obtained. [ka]

[0038] Examples of the organic peracid include performic acid, peracetic acid, perpropionic acid, m-chloroperbenzoic acid, trifluoroperacetic acid, and perbenzoic acid. These may be used in combination with a catalyst. Examples of the catalyst include alkalis such as sodium carbonate and acids such as sulfuric acid.

[0039] The amount of organic peracid used is, for example, 0.5 to 3 moles per mole of 3-cyclohexenylmethyl methacrylate. If the amount of organic peracid used is too small, problems such as loss due to polymerization of raw materials and target compounds, and high costs required for recovering unreacted 3-cyclohexenylmethyl methacrylate occur. On the other hand, if the amount of organic peracid used is too large, problems such as an increase in by-products due to excess organic peracid occur.

[0040] The epoxidation reaction can be carried out in the presence of a solvent. Examples of the solvent include aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, isopropylbenzene, diethylbenzene, and p-cymene; alicyclic hydrocarbons such as cyclohexane and decalin; aliphatic hydrocarbons such as hexane, heptane, octane, nonane, and decane; monohydric alcohols such as cyclohexanol, hexanol, heptanol, octanol, nonanol, and furfuryl alcohol; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; esters such as ethyl acetate, n-amyl acetate, cyclohexyl acetate, isoamyl propionate, and methyl benzoate; ethylene glycol, propylene glycol, ... Examples of the polyhydric alcohols include polyhydric alcohols and derivatives thereof (monoethers, monoesters, monoether monoesters, diethers, diesters, etc.), such as ethylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol dimethyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether; halogenated hydrocarbons, such as chloroform, methylene chloride, carbon tetrachloride, and chlorobenzene; and ethers, such as diethyl ether, diisopropyl ether, and dibutyl ether. These may be used alone or in combination of two or more.

[0041] The amount of the solvent used is, for example, about 0.2 to 10 times by weight of the raw material, 3-cyclohexenylmethyl methacrylate.

[0042] In the epoxidation reaction, stabilizers for organic peracids (e.g., ammonium hydrogen phosphate, potassium pyrophosphate, 2-ethylhexyl pyrophosphate, potassium 2-ethylhexyl pyrophosphate, potassium tripolyphosphate, 2-ethylhexyl tripolyphosphate, etc.), polymerization inhibitors (e.g., hydroquinone, hydroquinone monomethyl ether, p-benzoquinone, cresol, t-butylcatechol, 2,4-dimethyl-6-t-butylphenol, 2-t-butyl-4-methoxyphenol, 3-t-butyl-4-methoxyphenol, 2,6-di-t-butyl-p-cresol, 2,5-dihydroxy-p-quinone, piperidine, ethanolamine, α-nitroso-β-naphthol, etc.), etc. may be used as necessary. can be used).

[0043] The reaction temperature of the epoxidation reaction is, for example, 0 to 70° C. The reaction atmosphere is not particularly limited as long as it does not inhibit the reaction, and may be, for example, any of an air atmosphere, a nitrogen atmosphere, an argon atmosphere, etc. The epoxidation reaction may be carried out while blowing a molecular oxygen-containing gas into the reaction system in order to suppress polymerization.

[0044] The reaction may be carried out in any of a continuous system (piston flow, etc.), a semi-batch system, and a batch system.

[0045] (Water washing process) The water-washing step is a step of removing the organic peracid contained in the reaction product obtained through the epoxidation step and the organic acid which is the decomposition product thereof by washing with water.

[0046] The amount of water used is, for example, about 0.1 to 3 times (V / V) the reaction product. For washing with water, an equilibrium type extractor such as a mixer-settler type, an extraction tower, a centrifugal extractor, etc. can be used.

[0047] (Alkaline neutralization process, alkaline washing process) The alkaline neutralization step and alkaline water washing step are steps for removing organic peracids and organic acids contained in the reaction product with an alkali. Examples of the alkaline aqueous solution used include an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution, an aqueous sodium carbonate solution, and an aqueous sodium hydrogen carbonate solution. The amount of the alkaline aqueous solution used is, for example, about 0.1 to 10 times the weight of the reaction product (liquid to be treated) to be treated.

[0048] The alkali neutralization treatment and alkali washing can be carried out using an equilibrium type extractor such as a mixer-settler type, an extraction tower, a centrifugal extractor, or the like.

[0049] (Desolvation process) The desolvation step is a step of distilling off the solvent contained in the reaction product. For the desolvation, an evaporator such as a thin film evaporator or a flash can is usually used. The desolvation is preferably carried out in two stages in order to completely remove the solvent. The first stage of desolvation is preferably carried out at a heating temperature in the range of 50 to 100°C, preferably 50 to 70°C. In the first stage of desolvation, a bottom product having a solvent concentration of 3 to 50% by weight (preferably 10 to 20% by weight) is obtained. The second stage of desolvation is preferably carried out at a heating temperature in the range of 50 to 100°C, preferably 50 to 70°C. In the second stage of desolvation, a bottom product having a solvent concentration of, for example, 1% by weight or less is obtained.

[0050] In the solvent removal step, in order to make up for the polymerization inhibitor or organic peracid stabilizer lost in the water washing, alkali neutralization treatment, and alkali water washing, it is preferable to replenish the liquid to be treated with an appropriate amount of these. Also, in this step, it is preferable to introduce a molecular oxygen-containing gas having a polymerization inhibitory effect into the evaporator. The place where the molecular oxygen-containing gas is introduced can be selected arbitrarily, but it is preferable to blow the molecular oxygen-containing gas into the bottoms withdrawal line.

[0051] By undergoing the solvent removal step, a crude product of 3,4-epoxycyclohexylmethyl methacrylate with a purity of 94 to 97% by weight can be obtained.

[0052] (Low boiling process) The low-boiling point removal step is a step of distilling off components (e.g., solvent, water, low-boiling point impurities) contained in the reaction product that have a boiling point lower than that of 3,4-epoxycyclohexylmethyl methacrylate. This step makes it possible to reduce the content of the compounds represented by the formulas (a) to (c) mixed into the alicyclic epoxy compound product to an extremely low level. By reducing the content of the compounds represented by the formulas (a) to (c), it is possible to suppress coloration of the obtained alicyclic epoxy compound product and coloration over time, and to improve the physical properties, particularly the transparency, heat resistance, and mechanical properties, of the cured product obtained by curing the curable composition containing the alicyclic epoxy compound product.

[0053] As the distillation tower in the low boiling point removal step, for example, a plate tower, a packed tower, etc. can be used. The actual number of stages of the distillation tower is usually 10 or more (for example, 10 to 100 stages), preferably 20 or more (for example, 20 to 50 stages). The tower top pressure is usually 1 mmHg or less, preferably 0.3 mmHg or less, more preferably 0.1 mmHg or less. The tower top temperature is usually 100°C or less (for example, 40 to 100°C), preferably 85°C or less (for example, 50 to 85°C), more preferably 80°C or less (for example, 50 to 80°C). The tower bottom temperature is usually 140°C or less (for example, 60 to 140°C), preferably 130°C or less (for example, 70 to 130°C), more preferably 110°C or less (for example, 80 to 110°C). The heating temperature is usually 150° C. or lower (for example, 70 to 150° C.), and preferably 130° C. or lower (for example, 90 to 130° C.). The reflux ratio is usually 0.1 to 50, and preferably 1 to 10.

[0054] By increasing the number of actual plates of the distillation column or by increasing the reflux ratio, the amount of the compounds represented by the formulas (a) to (c) mixed into the product can be reduced. In addition, by lowering the bottom temperature or heating temperature of the distillation column, the formation of polymers and other undesirable by-products can be suppressed.

[0055] It is preferable to add a polymerization inhibitor to the liquid to be treated (liquid fed to the distillation column) to be subjected to the low boiling point distillation in order to suppress polymerization of the target compound during distillation. As the polymerization inhibitor, the above-mentioned examples can be used. Among them, preferred polymerization inhibitors include hydroquinone, p-benzoquinone, N-nitroso-N-phenylhydroxylamine ammonium salt, N-nitroso-N-phenylhydroxylamine aluminum salt, N-nitroso-N,N-diphenylamine, dibutylhydroxytoluene, 2,2,6,6-tetramethylpiperidine 1-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl, 4-acetamido-2,2,6,6-tetramethylpiperidine 1-oxyl, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine 1-oxyl, and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate. A molecular oxygen-containing gas having a polymerization-inhibiting effect may be blown into the distillation column, but from the viewpoint of maintaining a high degree of vacuum, blowing a molecular oxygen-containing gas into the distillation column is not preferred.

[0056] The amount of the polymerization inhibitor used is, for example, 0.005 to 1% by weight, preferably 0.005 to 0.5% by weight, more preferably 0.005 to 0.1% by weight, and particularly preferably 0.01 to 0.05% by weight, based on the liquid to be treated (liquid fed to the distillation column).

[0057] The ratio of the overhead distillate amount to the bottoms amount (the former / the latter) is, for example, 2 / 98 to 20 / 80, preferably 5 / 95 to 15 / 85, and more preferably 7 / 93 to 13 / 87.

[0058] In the low boiling point removal step, components having a boiling point lower than that of 3,4-epoxycyclohexylmethyl methacrylate are distilled off from the distillation column feed liquid through the top of the column, thereby obtaining 3,4-epoxycyclohexylmethyl methacrylate or a mixture of 3,4-epoxycyclohexylmethyl methacrylate and components having a boiling point higher than that of 3,4-epoxycyclohexylmethyl methacrylate, for example, as a bottoms liquid.

[0059] (High boiling process) The high boiling point removal step is a step of separating and removing components having a higher boiling point than 3,4-epoxycyclohexylmethyl methacrylate contained in the reaction product, for example, from the bottom of the column. This step can reduce the amount of the compound represented by formula (d) and polymers mixed into the alicyclic epoxy compound product to an extremely low level. By reducing the content of the compound represented by formula (d) and polymers, it is possible to improve the physical properties of the cured product of the curable composition containing the obtained alicyclic epoxy compound product, particularly the transparency, heat resistance, and mechanical properties.

[0060] As the distillation tower in the high boiling removal step, for example, a plate tower, a packed tower, etc. can be used. The number of actual stages of the distillation tower is usually 10 or more (for example, 10 to 100 stages), preferably 20 or more (for example, 20 to 50 stages). The pressure at the top of the tower is usually 1 mmHg or less, preferably 0.3 mmHg or less, more preferably 0.1 mmHg or less. The temperature at the top of the tower is usually 100°C or less (for example, 40 to 100°C), preferably 85°C or less (for example, 50 to 85°C), more preferably 80°C or less (for example, 50 to 80°C). The temperature at the bottom of the tower is usually 140°C or less (for example, 60 to 140°C), preferably 120°C or less (for example, 80 to 120°C), more preferably 110°C or less (for example, 80 to 110°C). The heating temperature is usually 150° C. or lower (for example, 70 to 150° C.), preferably 140° C. or lower (for example, 90 to 140° C.), and more preferably 130° C. or lower (for example, 90 to 130° C.). The reflux ratio is usually 0.1 to 50, and preferably 1 to 10.

[0061] By increasing the number of actual plates of the distillation column or by increasing the reflux ratio, the inclusion of the compound represented by formula (d) or polymers in the product can be reduced. In addition, by lowering the bottom temperature or heating temperature of the distillation column, the formation of polymers and other undesirable by-products can be suppressed.

[0062] A polymerization inhibitor may be added to the liquid to be treated (liquid fed to the distillation column) to be subjected to the high boiling point removal distillation in order to suppress polymerization of the target compound during distillation. As the polymerization inhibitor, those exemplified in the section on low boiling point removal distillation can be used. Although a molecular oxygen-containing gas having a polymerization inhibitor effect may be blown into the distillation column, from the viewpoint of maintaining a high degree of vacuum, blowing a molecular oxygen-containing gas into the distillation column is not preferable.

[0063] The amount of the polymerization inhibitor used is, for example, 0.005 to 1% by weight, preferably 0.005 to 0.5% by weight, more preferably 0.005 to 0.1% by weight, and particularly preferably 0.01 to 0.05% by weight, based on the liquid to be treated (liquid fed to the distillation column).

[0064] The ratio of the overhead distillate amount to the bottoms amount (the former / the latter) is, for example, 80 / 20 to 98 / 2, preferably 85 / 15 to 95 / 5, and more preferably 87 / 13 to 93 / 7.

[0065] In the high boiling point removal step, components having a higher boiling point than 3,4-epoxycyclohexylmethyl methacrylate are discharged from the distillation column feed liquid, for example, from the bottom of the column, to obtain 3,4-epoxycyclohexylmethyl methacrylate or a mixture of 3,4-epoxycyclohexylmethyl methacrylate and components having a lower boiling point than that, for example, as a bottoms liquid.

[0066] In this way, by subjecting the reaction product to treatments for removing low boiling points and high boiling points, it is possible to obtain an alicyclic epoxy compound product having a high purity of 3,4-epoxycyclohexylmethyl methacrylate and a low content of specific impurities.

[0067] [Curable composition] The curable composition of the present invention contains the above-mentioned alicyclic epoxy compound product (high purity 3,4-epoxycyclohexylmethyl methacrylate).

[0068] The curable composition of the present invention contains, as the curable compound (A), 3,4-epoxycyclohexylmethyl methacrylate contained in the alicyclic epoxy compound product, and may also contain one or more other curable compounds.

[0069] Examples of other curable compounds include a compound (A1) having a cationically polymerizable group and a radically polymerizable group other than 3,4-epoxycyclohexylmethyl methacrylate, a cationically polymerizable compound (A2) having no radically polymerizable group, and a radically polymerizable compound (A3) having no cationically polymerizable group.

[0070] Examples of the compound (A1) having a cationically polymerizable group and a radically polymerizable group other than 3,4-epoxycyclohexylmethyl methacrylate include 3,4-epoxycyclohexyl(meth)acrylate, 3,4-epoxycyclohexylmethyl acrylate, 2-(3,4-epoxycyclohexyl)ethyl(meth)acrylate, 2-(3,4-epoxycyclohexylmethyloxy)ethyl(meth)acrylate, 3-(3,4-epoxycyclohexylmethyloxy)propyl ... Polymerizable unsaturated compounds containing an epoxy group-containing alicyclic carbon ring such as a 3,4-epoxycyclohexane ring, such as (meth)acrylate (e.g., (meth)acrylic acid ester derivatives); polymerizable unsaturated compounds containing a 5,6-epoxy-2-bicyclo[2.2.1]heptane ring, such as 5,6-epoxy-2-bicyclo[2.2.1]heptyl (meth)acrylate (e.g., (meth)acrylic acid ester derivatives); epoxidized dicyclopentenyl (meth)acrylate [3,4-epoxytricyclo[5.2.1.0 2,6 ]Decan-9-yl (meth)acrylate, 3,4-epoxytricyclo[5.2.1.0 2,6 ]decan-8-yl (meth)acrylate, or mixtures thereof], epoxidized dicyclopentenyloxyethyl (meth)acrylate [2-(3,4-epoxytricyclo[5.2.1.0 2,6 ]decan-9-yloxy)ethyl (meth)acrylate, 2-(3,4-epoxytricyclo[5.2.1.0 2,6]decane-8-yloxy)ethyl (meth)acrylate, or a mixture thereof], 3,4-epoxytricyclo[5.2.1.0 such as epoxidized dicyclopentenyloxybutyl (meth)acrylate, and epoxidized dicyclopentenyloxyhexyl (meth)acrylate 2,6 ] Polymerizable unsaturated compounds containing a decane ring (such as (meth)acrylic acid ester derivatives).

[0071] The compound (A1) having a cationically polymerizable group and a radically polymerizable group other than 3,4-epoxycyclohexylmethyl methacrylate can be used alone or in combination of two or more kinds.

[0072] Examples of the cationically polymerizable compound (A2) having no radically polymerizable group include epoxy compounds, oxetane compounds, and vinyl ether compounds.

[0073] The epoxy compounds include alicyclic epoxy compounds, aromatic epoxy compounds, and aliphatic epoxy compounds.

[0074] The alicyclic epoxy compounds include the following compounds: (1) Compounds having an epoxy group (sometimes referred to as an "alicyclic epoxy group" in this specification) composed of two adjacent carbon atoms and an oxygen atom that constitute an alicyclic ring in the molecule (excluding 3,4-epoxycyclohexylmethyl methacrylate) (2) Compounds in which an epoxy group is directly bonded to an alicyclic ring via a single bond (3) Compounds having an alicyclic ring and a glycidyl ether group in the molecule (glycidyl ether type epoxy compounds)

[0075] An example of the compound (1) having an alicyclic epoxy group is a compound represented by the following formula (1). [ka] (wherein X represents a single bond or a linking group).

[0076] In the above formula (1), X represents a single bond or a linking group (a divalent group having one or more atoms). Examples of the linking group include a divalent hydrocarbon group, an alkenylene group in which a part or all of the carbon-carbon double bonds are epoxidized, a carbonyl group, an ether bond, an ester bond, a carbonate group, an amide group, and a group in which a plurality of these groups are linked together. The cyclohexene oxide group in formula (1) may have a substituent (e.g., an alkyl group, etc.) bonded thereto.

[0077] Examples of the divalent hydrocarbon group include linear or branched alkylene groups and divalent alicyclic hydrocarbon groups having 1 to 18 carbon atoms. Examples of the linear or branched alkylene groups having 1 to 18 carbon atoms include methylene, methylmethylene, dimethylmethylene, ethylene, propylene, and trimethylene. Examples of the divalent alicyclic hydrocarbon group include cycloalkylene groups (including cycloalkylidene groups) such as 1,2-cyclopentylene, 1,3-cyclopentylene, cyclopentylidene, 1,2-cyclohexylene, 1,3-cyclohexylene, 1,4-cyclohexylene, and cyclohexylidene.

[0078] Examples of the alkenylene group in the alkenylene group in which some or all of the carbon-carbon double bonds have been epoxidized (sometimes referred to as "epoxidized alkenylene group") include linear or branched alkenylene groups having 2 to 8 carbon atoms, such as vinylene group, propenylene group, 1-butenylene group, 2-butenylene group, butadienylene group, pentenylene group, hexenylene group, heptenylene group, and octenylene group. In particular, the epoxidized alkenylene group is preferably an alkenylene group in which all of the carbon-carbon double bonds have been epoxidized, and more preferably an alkenylene group in which all of the carbon-carbon double bonds have been epoxidized and have 2 to 4 carbon atoms.

[0079] Representative examples of the compound represented by the above formula (1) include (3,4,3',4'-diepoxy)bicyclohexyl, bis(3,4-epoxycyclohexylmethyl)ether, 1,2-epoxy-1,2-bis(3,4-epoxycyclohexane-1-yl)ethane, 2,2-bis(3,4-epoxycyclohexane-1-yl)propane, 1,2-bis(3,4-epoxycyclohexane-1-yl)ethane, and compounds represented by the following formulas (1-1) to (1-7). L in the following formula (1-4) is an alkylene group having 1 to 8 carbon atoms, and among these, a linear or branched alkylene group having 1 to 3 carbon atoms such as a methylene group, an ethylene group, a propylene group, or an isopropylene group is preferred. n in the following formulas (1-4) and (1-6) 1 , n 2 Each represents an integer from 1 to 30.

[0080] [ka]

[0081] The compound (1) having an alicyclic epoxy group includes, in addition to the compound represented by the above formula (1), compounds having three or more alicyclic epoxy groups in the molecule represented by the following formulas (1-8) and (1-9), and compounds having one alicyclic epoxy group in the molecule represented by the following formula (1-10). 3 ~n 8 Each represents an integer from 1 to 30.

[0082] [ka]

[0083] [ka]

[0084] Examples of the compound (2) in which an epoxy group is directly bonded to the alicyclic ring via a single bond include compounds represented by the following formula (2). [ka]

[0085] In formula (2), R' is a group (p-valent organic group) obtained by removing p hydroxyl groups from the structural formula of p-valent alcohol, and p, n 9 Each represents a natural number. p-valent alcohol [R'(OH) p Examples of the alkyl group include polyhydric alcohols (polyhydric alcohols having 1 to 15 carbon atoms) such as 2,2-bis(hydroxymethyl)-1-butanol. p is preferably an integer of 1 to 6, and n 9 is preferably 1 to 30. When p is 2 or more, n in each group in [ ] (in the outer square brackets) 9 may be the same or different. Specific examples of the compound represented by the above formula (2) include 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol [e.g., trade name "EHPE3150" (manufactured by Daicel Corporation)].

[0086] Examples of the glycidyl ether type epoxy compound (3) include glycidyl ethers of alicyclic alcohols (particularly, alicyclic polyhydric alcohols). More specifically, examples of the glycidyl ethers include hydrogenated bisphenol A type epoxy compounds, hydrogenated bisphenol F type epoxy compounds, hydrogenated biphenol type epoxy compounds, hydrogenated phenol novolac type epoxy compounds, and hydrogenated cresol novolac type epoxy compounds.

[0087] Examples of the aromatic epoxy compound include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, biphenol type epoxy compounds, phenol novolac type epoxy compounds, and cresol novolac type epoxy compounds.

[0088] Examples of the aliphatic epoxy compound include glycidyl ethers of q-valent alcohols (where q is a natural number) that do not have a cyclic structure; glycidyl esters of monovalent or polyvalent carboxylic acids (e.g., acetic acid, propionic acid, butyric acid, stearic acid, adipic acid, sebacic acid, maleic acid, itaconic acid, etc.); epoxidized products of oils and fats having double bonds, such as epoxidized linseed oil, epoxidized soybean oil, and epoxidized castor oil; and epoxidized products of polyolefins (including polyalkadienes), such as epoxidized polybutadiene.

[0089] Examples of the oxetane compound include 3,3-bis(vinyloxymethyl)oxetane, 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane, 3-ethyl-3-(hydroxymethyl)oxetane, 3-ethyl-3-[(phenoxy)methyl]oxetane, 3-ethyl-3-(hexyloxymethyl)oxetane, 3-ethyl-3-(chloromethyl)oxetane, 3,3-bis(chloromethyl)oxetane, 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene, and bis(vinyloxymethyl)oxetane. Examples of the bis([1-ethyl(3-oxetanyl)]methyl)ether include 4,4'-bis[(3-ethyl-3-oxetanyl)methoxymethyl]bicyclohexyl, 4,4'-bis[3-ethyl-(3-oxetanyl)methoxymethyl]biphenyl, 1,4-bis[(3-ethyl-3-oxetanyl)methoxymethyl]cyclohexane, 1,4-bis([(3-ethyl-3-oxetanyl)methoxy]methyl)benzene, 3-ethyl-3([(3-ethyloxetan-3-yl)methoxy]methyl)oxetane, and xylylene bisoxetane.

[0090] Examples of the vinyl ether compound include aryl vinyl ethers such as phenyl vinyl ether; alkyl vinyl ethers such as n-butyl vinyl ether and n-octyl vinyl ether; cycloalkyl vinyl ethers such as cyclohexyl vinyl ether; vinyl ethers having a hydroxyl group such as 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether and 2-hydroxybutyl vinyl ether; and polyfunctional vinyl ethers such as hydroquinone divinyl ether, 1,4-butanediol divinyl ether, cyclohexane divinyl ether, cyclohexane dimethanol divinyl ether, ethylene glycol divinyl ether, diethylene glycol divinyl ether and triethylene glycol divinyl ether.

[0091] The cationically polymerizable compound (A2) having no radically polymerizable group can be used alone or in combination of two or more kinds.

[0092] Examples of the radical polymerizable compound (A3) having no cationically polymerizable group include (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and dodecyl (meth)acrylate [e.g., (meth)acrylic acid C 1-10alkyl esters, etc.]; (meth)acrylic acid esters having an aromatic ring structure in the molecule, such as benzyl (meth)acrylate; (meth)acrylic acid esters containing a cyclohexane ring, such as cyclohexyl (meth)acrylate, cyclohexylmethyl (meth)acrylate, 2-(cyclohexyl)ethyl (meth)acrylate, 2-(cyclohexylmethyloxy)ethyl (meth)acrylate, and 3-(cyclohexylmethyloxy)propyl (meth)acrylate; (meth)acrylic acid esters containing a 2-bicyclo[2.2.1]heptane ring, such as 2-bicyclo[2.2.1]heptyl (meth)acrylate; (meth)acrylic acid esters containing an adamantane ring, such as 1-adamantyl (meth)acrylate; dicyclopentanyl (meth)acrylate {tricyclo[5.2.1.0 2,6 ]Decan-9-yl (meth)acrylate, tricyclo[5.2.1.0 2,6 ]decan-8-yl (meth)acrylate, or mixtures thereof}, dicyclopentenyl (meth)acrylate {tricyclo[5.2.1.0 2,6 ]dec-3-en-9-yl (meth)acrylate, tricyclo[5.2.1.0 2,6 ]dec-3-en-8-yl (meth)acrylate, or a mixture thereof}, dicyclopentenyloxyethyl (meth)acrylate {2-(tricyclo[5.2.1.0 2,6 ]decan-9-yloxy)ethyl (meth)acrylate, 2-(tricyclo[5.2.1.0 2,6 ]decan-8-yloxy)ethyl (meth)acrylate, or a mixture thereof}, dicyclopentenyloxybutyl (meth)acrylate, dicyclopentenyloxyhexyl (meth)acrylate, or other tricyclo[5.2.1.0 2,6](Meth)acrylic acid esters having an alicyclic structure, such as (meth)acrylic acid esters containing a decane ring; styrene-based compounds such as styrene, vinyl toluene, α-methylstyrene, and vinyl naphthalene; vinyl ether compounds such as methyl vinyl ether, butyl vinyl ether, and phenyl vinyl ether; (meth)acrylic acid esters having a hydroxyl group, such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate; methoxydiethylene glycol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, and isooctyloxydiethylene glycol Examples of the polyalkylene glycol (meth)acrylate include alkoxypolyalkylene glycol (meth)acrylates such as glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, and methoxypolyethylene glycol (meth)acrylate; (meth)acrylic acid esters having an amino group such as 2-aminoethyl (meth)acrylate; heterocyclic compounds having a vinyl group such as 2-vinylpyrrolidone (nitrogen-containing heterocyclic compounds, etc.); α,β-unsaturated carboxylic acids and their acid anhydrides (maleic anhydride, itaconic anhydride, etc.) such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, and fumaric acid; and polyfunctional (meth)acrylates.

[0093] The radically polymerizable compound (A3) having no cationically polymerizable group can be used alone or in combination of two or more kinds.

[0094] The proportion of 3,4-epoxycyclohexylmethyl methacrylate in the total amount (100% by weight) of the curable compound (A) contained in the curable composition is, for example, 10% by weight or more (e.g., 10 to 100% by weight), preferably 30% by weight or more, more preferably 50% by weight or more, and even more preferably 80% by weight or more.

[0095] The curable composition of the present invention preferably contains, in addition to the curable compound (A), for example, a curing agent (B) and a curing accelerator (C) or a curing catalyst (D).

[0096] The proportion of the total content of the curable compound (A), the curing agent (B), and the curing accelerator (C) in the total amount of the curable composition of the present invention is, for example, 5% by weight or more, preferably 30% by weight or more, more preferably 60% by weight or more, even more preferably 80% by weight or more, particularly preferably 90% by weight or more, and especially preferably 95% by weight or more.

[0097] The proportion of the total content of the curable compound (A) and the curing catalyst (D) in the total amount of the curable composition of the present invention is, for example, 5% by weight or more, preferably 30% by weight or more, more preferably 60% by weight or more, even more preferably 80% by weight or more, particularly preferably 90% by weight or more, and especially preferably 95% by weight or more.

[0098] Therefore, the content of compounds other than the curable compound (A), the curing agent (B), the curing accelerator (C), and the curing catalyst (D) in the total amount of the curable composition of the present invention is, for example, 95% by weight or less, preferably 50% by weight or less, and more preferably 40% by weight or less.

[0099] (Hardening agent (B)) As the curing agent (B), for example, known or conventional curing agents for epoxy resins, such as acid anhydrides (acid anhydride-based curing agents), amines (amine-based curing agents), polyamide resins, imidazoles (imidazole-based curing agents), polymercaptans (polymercaptan-based curing agents), phenols (phenol-based curing agents), polycarboxylic acids, dicyandiamides, organic acid hydrazides, etc., can be used. These can be used alone or in combination of two or more.

[0100] Examples of the acid anhydrides include methyltetrahydrophthalic anhydride (4-methyltetrahydrophthalic anhydride, 3-methyltetrahydrophthalic anhydride, etc.), methylhexahydrophthalic anhydride (4-methylhexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, etc.), dodecenyl succinic anhydride, methyl endomethylene tetrahydrophthalic anhydride, phthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylcyclohexene diphthalate, and the like. Examples of the acid anhydride include carboxylic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenone tetracarboxylic anhydride, nadic anhydride, methyl nadic anhydride, hydrogenated methyl nadic anhydride, 4-(4-methyl-3-pentenyl)tetrahydrophthalic anhydride, succinic anhydride, adipic anhydride, sebacic anhydride, dodecanedioic anhydride, methylcyclohexene tetracarboxylic anhydride, vinyl ether maleic anhydride copolymer, alkylstyrene-maleic anhydride copolymer, etc. Among these, from the viewpoint of handling, acid anhydrides that are liquid at 25° C. [for example, methyl tetrahydrophthalic anhydride, methyl hexahydrophthalic anhydride, dodecenyl succinic anhydride, methyl end methylene tetrahydrophthalic anhydride, etc.] are preferred.

[0101] Examples of the amines include aliphatic polyamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenediamine, diethylaminopropylamine, and polypropylenetriamine; menthenediamine, isophoronediamine, bis(4-amino-3-methyldicyclohexyl)methane, diaminodicyclohexylmethane, bis(aminomethyl)cyclohexane, N-aminoethylpiperazine, 3,9-bis(3-aminopropyl)-3,4,8 alicyclic polyamines such as 1,10-tetraoxaspiro[5,5]undecane, etc.; mononuclear polyamines such as m-phenylenediamine, p-phenylenediamine, tolylene-2,4-diamine, tolylene-2,6-diamine, mesitylene-2,4-diamine, 3,5-diethyltolylene-2,4-diamine, and 3,5-diethyltolylene-2,6-diamine; and aromatic polyamines such as biphenylenediamine, 4,4-diaminodiphenylmethane, 2,5-naphthylenediamine, and 2,6-naphthylenediamine.

[0102] Examples of the polyamide resin include polyamide resins having either or both of a primary amino group and a secondary amino group in the molecule.

[0103] Examples of the imidazoles include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl- Examples of the compound include 2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2-methylimidazolium isocyanurate, 2-phenylimidazolium isocyanurate, 2,4-diamino-6-[2-methylimidazolyl-(1)]-ethyl-s-triazine, and 2,4-diamino-6-[2-ethyl-4-methylimidazolyl-(1)]-ethyl-s-triazine.

[0104] Examples of the polymercaptans include liquid polymercaptan and polysulfide resin.

[0105] Examples of the phenols include aralkyl resins such as novolac type phenol resins, novolac type cresol resins, p-xylylene modified phenol resins, and p-xylylene / m-xylylene modified phenol resins, terpene modified phenol resins, dicyclopentadiene modified phenol resins, and triphenolpropane.

[0106] Examples of the polycarboxylic acids include adipic acid, sebacic acid, terephthalic acid, trimellitic acid, and carboxy group-containing polyesters.

[0107] As the curing agent (B), from the viewpoint of the heat resistance and transparency of the obtained cured product, acid anhydrides (acid anhydride-based curing agents) are preferable. For example, commercially available products such as trade names "RIKACID MH-700" and "RIKACID MH-700F" (both manufactured by New Japan Chemical Co., Ltd.) and trade name "HN-5500" (manufactured by Hitachi Chemical Co., Ltd.) can be used.

[0108] The content (mixture amount) of the curing agent (B) is preferably 50 to 200 parts by weight, more preferably 80 to 150 parts by weight, based on 100 parts by weight of the total amount of the compounds having an epoxy group contained in the curable composition. More specifically, when an acid anhydride is used as the curing agent (B), it is preferable to use it in a ratio of 0.5 to 1.5 equivalents per equivalent of the epoxy group in all the compounds having an epoxy group contained in the curable composition of the present invention. By making the content of the curing agent (B) 50 parts by weight or more, the curing can be sufficiently advanced, and the toughness of the obtained cured product tends to be improved. On the other hand, by making the content of the curing agent (B) 200 parts by weight or less, coloring is suppressed, and a cured product having excellent hue tends to be obtained.

[0109] (Cure accelerator (C)) When the curable composition of the present invention contains a curing agent (B), it is preferable that the composition further contains a curing accelerator (C). The curing accelerator (C) has an effect of accelerating the reaction rate when a compound having an epoxy group (oxiranyl group) reacts with the curing agent (B).

[0110] Examples of the curing accelerator (C) include 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) or a salt thereof (e.g., phenol salt, octylate salt, p-toluenesulfonate, formate salt, tetraphenylborate salt, etc.), 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) or a salt thereof (e.g., phenol salt, octylate salt, p-toluenesulfonate, formate salt, tetraphenylborate salt, etc.), benzyldimethylamine, and 2,4,6-tris(dimethylaminomethyl)phenol. tertiary amines such as N,N-dimethylcyclohexylamine, imidazoles such as 2-ethyl-4-methylimidazole and 1-cyanoethyl-2-ethyl-4-methylimidazole, phosphoric acid esters, phosphines such as triphenylphosphine and tris(dimethoxy)phosphine, phosphonium compounds such as tetraphenylphosphonium tetra(p-tolyl)borate, organic metal salts such as zinc octylate, tin octylate and zinc stearate, metal chelates such as aluminum acetylacetone complex, etc. These can be used alone or in combination of two or more.

[0111] As the curing accelerator (C), for example, commercially available products such as trade names "U-CAT SA 506", "U-CAT SA 102", "U-CAT 5003", "U-CAT 18X", and "U-CAT 12XD" (developed products) (all manufactured by San-Apro Co., Ltd.); trade names "TPP-K" and "TPP-MK" (all manufactured by Hokko Chemical Industry Co., Ltd.); and trade name "PX-4ET" (manufactured by Nippon Chemical Industry Co., Ltd.) can be used.

[0112] The content (mixture amount) of the curing accelerator (C) is preferably 0.01 to 5 parts by weight, more preferably 0.02 to 3 parts by weight, and further preferably 0.03 to 3 parts by weight, based on 100 parts by weight of the curing agent (B). By making the content of the curing accelerator (C) 0.01 parts by weight or more, a more efficient curing acceleration effect tends to be obtained. On the other hand, by making the content of the curing accelerator (C) 5 parts by weight or less, coloring is suppressed, and a cured product with excellent hue tends to be obtained.

[0113] (Curing catalyst (D)) The curable composition of the present invention may contain a curing catalyst (D) instead of the curing agent (B). The curing catalyst (D) has a function of initiating and / or accelerating the curing reaction (polymerization reaction) of a curable (polymerizable) compound such as 3,4-epoxycyclohexylmethyl methacrylate, thereby curing the curable composition. Examples of the curing catalyst (D) include cationic polymerization initiators (photocationic polymerization initiators, thermal cationic polymerization initiators, etc.) that generate cationic species by applying light irradiation or heat treatment, and initiate polymerization, Lewis acid-amine complexes, Bronsted acid salts, imidazoles, radical polymerization initiators (photoradical polymerization initiators, thermal radical polymerization initiators), etc. These may be used alone or in combination of two or more.

[0114] Examples of the photocationic polymerization initiator include hexafluoroantimonate salts, pentafluorohydroxyantimonate salts, hexafluorophosphate salts, and hexafluoroarsenate salts. More specifically, examples of the photocationic polymerization initiator include sulfonium salts (particularly triarylsulfonium salts) such as triarylsulfonium hexafluorophosphate (e.g., p-phenylthiophenyldiphenylsulfonium hexafluorophosphate) and triarylsulfonium hexafluoroantimonate; iodonium salts such as diaryliodonium hexafluorophosphate, diaryliodonium hexafluoroantimonate, bis(dodecylphenyl)iodonium tetrakis(pentafluorophenyl)borate, and iodonium [4-(4-methylphenyl-2-methylpropyl)phenyl]hexafluorophosphate; phosphonium salts such as tetrafluorophosphonium hexafluorophosphate; and pyridinium salts such as N-hexylpyridinium tetrafluoroborate. As the photocationic polymerization initiator, for example, commercially available products such as "UVACURE1590" (manufactured by Daicel-Cytec Co., Ltd.); "CD-1010", "CD-1011", and "CD-1012" (all manufactured by Sartomer Co., Ltd., USA); "Irgacure 264" (manufactured by BASF); and "CIT-1682" (manufactured by Nippon Soda Co., Ltd.) can be preferably used.

[0115] Examples of the thermal cationic polymerization initiator include aryl diazonium salts, aryl iodonium salts, aryl sulfonium salts, and allene ion complexes. Commercially available products such as trade names "PP-33", "CP-66", and "CP-77" (all manufactured by ADEKA CORPORATION); trade name "FC-509" (manufactured by 3M); trade name "UVE1014" (manufactured by GE); trade names "SAN-AID SI-60L", "SAN-AID SI-80L", "SAN-AID SI-100L", "SAN-AID SI-110L", and "SAN-AID SI-150L" (all manufactured by Sanshin Chemical Industry Co., Ltd.); and trade name "CG-24-61" (manufactured by BASF) can be preferably used.

[0116] Examples of the Lewis acid-amine complex include BF3·n-hexylamine, BF3·monoethylamine, BF3·benzylamine, BF3·diethylamine, BF3·piperidine, BF3·triethylamine, BF3·aniline, BF4·n-hexylamine, BF4·monoethylamine, BF4·benzylamine, BF4·diethylamine, BF4·piperidine, BF4·triethylamine, BF4·aniline, PF5·ethylamine, PF5·isopropylamine, PF5·butylamine, PF5·laurylamine, PF5·benzylamine, and AsF5·laurylamine.

[0117] Examples of the Bronsted acid salts include aliphatic sulfonium salts, aromatic sulfonium salts, iodonium salts, and phosphonium salts.

[0118] Examples of the imidazoles include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl- Examples of the compound include 2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2-methylimidazolium isocyanurate, 2-phenylimidazolium isocyanurate, 2,4-diamino-6-[2-methylimidazolyl-(1)]-ethyl-s-triazine, and 2,4-diamino-6-[2-ethyl-4-methylimidazolyl-(1)]-ethyl-s-triazine.

[0119] As the radical polymerization initiator, a thermal radical polymerization initiator or a photoradical polymerization initiator can be used. Examples of the thermal radical polymerization initiator include azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), dimethyl-2,2'-azobis(2-methylpropionate), 2,2'-azobis(isobutyric acid)dimethyl, diethyl-2,2'-azobis(2-methylpropionate), and dibutyl-2,2'-azobis(2-methylpropionate), organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butyl peroxypivalate, and 1,1-bis(t-butylperoxy)cyclohexane, and hydrogen peroxide. When a peroxide is used as a radical polymerization initiator, it may be combined with a reducing agent to form a redox type initiator. The radical polymerization initiator and the chain transfer agent may be used in combination.

[0120] Examples of the photoradical polymerization initiator include benzophenones such as benzophenone; acetophenone benzyl, benzyl dimethyl ketone; benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; acetophenones such as dimethoxyacetophenone, dimethoxyphenylacetophenone, and diethoxyacetophenone; diphenyl disulfite, methyl orthobenzoylbenzoate, ethyl 4-dimethylaminobenzoate [Kayacure EPA, manufactured by Nippon Kayaku Co., Ltd., and the like], 2,4-diethylthioxanthone [Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd., and the like], 2-methyl-1-[4-(methyl)phenyl]-2-morpholinopropanone-1 [Ciba-Geigy Co., Ltd. Irgacure 907, etc.], tetra(t-butylperoxycarbonyl)benzophenone, benzil, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 4,4-bisdiethylaminobenzophenone, 2,2'-bis(2-chlorophenyl)-4,5,4',5'-tetraphenyl-1,2'-biimidazole [B-CIM manufactured by Tsuchitani Chemical Co., Ltd., etc.] can be used alone or in combination, and a photosensitizer can be added as necessary.

[0121] The content (blended amount) of the curing catalyst (D) is preferably 0.01 to 10 parts by weight, more preferably 0.02 to 7 parts by weight, and further preferably 0.03 to 5 parts by weight, based on 100 parts by weight of the curable (polymerizable) compound contained in the curable composition. By using the curing catalyst (D) within the above range, the curing speed of the curable composition increases, and the heat resistance and transparency of the cured product tend to be improved in a well-balanced manner.

[0122] In addition to the above, the curable composition of the present invention may contain one or more additives as necessary. Examples of the additives include polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and glycerin; antifoaming agents, leveling agents, silane coupling agents, surfactants, inorganic fillers, flame retardants, colorants, ion adsorbents, pigments, fluorescent materials, and mold release agents.

[0123] The curable composition of the present invention can be prepared by stirring and mixing the above-mentioned components in a heated state as necessary. For the stirring and mixing, known or commonly used stirring and mixing means can be used, such as various mixers such as dissolvers and homogenizers, kneaders, roll mills, bead mills, and planetary stirring devices. After stirring and mixing, the mixture may be degassed under vacuum.

[0124] The viscosity of the curable composition of the present invention at 25° C. is, for example, 100 to 50,000 mPa·s, preferably 200 to 45,000 mPa·s, and particularly preferably 300 to 40,000 mPa·s. By controlling the viscosity at 25° C. within the above range, workability during casting and coating is improved, and the cured product tends to be less susceptible to defects due to poor casting or coating.

[0125] The curable composition of the present invention contains at least 3,4-epoxycyclohexylmethyl methacrylate having both a cationic polymerizable group and a radical polymerizable group. Therefore, the curable composition of the present invention can be cured by cationic polymerization, radical polymerization, or a combination of these. When cationic polymerization and radical polymerization are combined, radical polymerization may be performed first and then cationic polymerization, or cationic polymerization may be performed first and then radical polymerization, or further, cationic polymerization and radical polymerization may be performed simultaneously.

[0126] The curable composition of the present invention has a fast curing property. For example, when cationic polymerization (curing) is performed using a curing agent, the curing time (gel time) at 120°C is, for example, 2500 seconds or less, preferably 2400 seconds or less. When cationic polymerization (curing) is performed using a curing catalyst (thermal cationic polymerization initiator), the curing time (gel time) at 80°C is, for example, 2000 seconds or less. Furthermore, when cationic polymerization (curing) and radical polymerization are simultaneously performed using a combination of a thermal cationic polymerization initiator and a thermal radical polymerization initiator as a curing catalyst, the curing time (gel time) at 80°C is, for example, 900 seconds or less.

[0127] The heating temperature (curing temperature) when curing the curable composition of the present invention is, for example, 60 to 200°C, preferably 80 to 160°C, when a curing agent is used, and is, for example, 45 to 160°C, preferably 60 to 120°C, when a curing catalyst is used. The heating time (curing time) is, for example, 0.5 to 20 hours, preferably 1 to 10 hours. If the heating temperature or heating time is below the above range, curing becomes insufficient, and conversely, if it exceeds the above range, decomposition of the resin component may occur, so neither is preferable. The curing conditions depend on various conditions, but can be appropriately adjusted, for example, by shortening the heating time when the heating temperature is high, and lengthening the heating time when the heating temperature is low.

[0128] When the curable composition of the present invention is cured, it can be cured in an extremely short time by irradiating it with active energy rays such as ultraviolet rays or electron beams. As a light source for irradiating ultraviolet rays, a high pressure mercury lamp, an ultra-high pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, etc. are used. The irradiation time varies depending on the type of light source, the distance between the light source and the substrate, and other conditions, but is at most several tens of seconds, and is usually several seconds. Usually, an irradiation source with a lamp output of about 80 to 300 W / cm is used. In the case of electron beam irradiation, it is preferable to use an electron beam having an energy in the range of 50 to 1000 keV, and to set the irradiation amount to 2 to 5 Mrad. After irradiation with active energy rays, heating (post-cure) may be performed as necessary to promote curing.

[0129] [Cured product] The cured product of the present invention is obtained by curing the above-mentioned curable composition. The cured product of the present invention includes a cured product obtained by cationic polymerization of the curable composition of the present invention, a cured product obtained by radical polymerization of the curable composition of the present invention, and a cured product obtained by cationic polymerization and radical polymerization of the curable composition of the present invention. The cured product of the present invention (particularly, a cured product obtained by cationic polymerization, or a cured product obtained by cationic polymerization and radical polymerization) is excellent in transparency and heat resistance.

[0130] The cured product has excellent transparency. The light transmittance of the light having a wavelength of 400 nm [thickness 3 mm] is, for example, 70% or more, preferably 80% or more, and particularly preferably 90% or more. Since the curable composition of the present invention forms a cured product having excellent transparency, when used as a sealant or a die attachment paste agent for an optical semiconductor element in an optical semiconductor device, the luminous intensity emitted from the optical semiconductor device tends to be higher.

[0131] The cured product has excellent heat resistance. The glass transition temperature (Tg) of the cured product obtained by cationic polymerization is, for example, 60° C. or higher, and preferably 70° C. or higher, and the cured product obtained by cationic polymerization and radical polymerization is, for example, 140° C. or higher.

[0132] In addition, the cured product has excellent heat resistance and can maintain high light transmittance even in a high temperature environment. For example, after heating the cured product at 120°C for 300 hours, the retention rate of light transmittance of 400 nm (calculated by the following formula) is, for example, 70% or more, preferably 80% or more. Light transmittance maintenance rate = (Light transmittance of cured material after heating) / (Light transmittance of cured material before heating) x 100

[0133] The curable composition of the present invention can be used for various applications, such as a sealant, an adhesive, a coating agent, an electrical insulating material, a laminate, an ink, a sealant, a resist, a composite material, a transparent substrate, a transparent sheet, a transparent film, an optical element, an optical lens, photolithography, electronic paper, a touch panel, a solar cell substrate, an optical waveguide, a light guide plate, and a holographic memory.

[0134] <Sealant> The encapsulant of the present invention is characterized by containing the above-mentioned curable composition. The encapsulant of the present invention can be preferably used for encapsulating an optical semiconductor (optical semiconductor element) in an optical semiconductor device. By using the encapsulant of the present invention, the optical semiconductor element can be encapsulated with a cured product (=encapsulant) having excellent transparency and heat resistance.

[0135] The content of the curable composition in the total amount of the sealant of the present invention is, for example, 50% by weight or more, preferably 60% by weight or more, and particularly preferably 70% by weight or more. The sealant of the present invention may consist of only the curable composition.

[0136] <Adhesive> The adhesive of the present invention is characterized by containing the above-mentioned curable composition. The adhesive of the present invention can be used in various applications requiring excellent transparency and heat resistance, such as applications for adhering and fixing a member or the like to an adherend, specifically, a die attachment paste for adhering and fixing an optical semiconductor element to a metal electrode in an optical semiconductor device, a lens adhesive for fixing a lens of a camera or the like to an adherend or bonding lenses together, and an optical film adhesive for fixing an optical film (e.g., a polarizer, a polarizer protective film, a retardation film, etc.) to an adherend or bonding optical films together or an optical film to another film.

[0137] The adhesive of the present invention can be particularly preferably used as a die attachment paste (or die bond agent). By using the adhesive of the present invention as a die attachment paste, an optical semiconductor device can be obtained in which an optical semiconductor element is attached to an electrode by a cured product having excellent transparency and heat resistance.

[0138] The content of the curable composition in the total amount of the adhesive of the present invention is, for example, 50% by weight or more, preferably 60% by weight or more, and particularly preferably 70% by weight or more. The adhesive of the present invention may consist of only the curable composition.

[0139] <Coating agent> The coating agent of the present invention is characterized by containing the above-mentioned curable composition. The coating agent of the present invention can be used in various applications in which excellent transparency and heat resistance are particularly required.

[0140] The content of the curable composition in the total amount of the coating agent of the present invention is, for example, 5% by weight or more, preferably 30% by weight or more, more preferably 60% by weight or more, and particularly preferably 70% by weight or more. The coating agent of the present invention may be composed of only the curable composition. It may also contain a solvent.

[0141] <Optical components> The optical member of the present invention is characterized by comprising a cured product of the above-mentioned curable composition. Examples of the optical member include an optical semiconductor device in which an optical semiconductor element is sealed with the cured product of the above-mentioned curable composition, an optical semiconductor device in which an optical semiconductor element is bonded to an electrode with the cured product of the above-mentioned curable composition, and an optical semiconductor device in which an optical semiconductor element is bonded to an electrode with the cured product of the above-mentioned curable composition and the optical semiconductor element is sealed with the cured product of the above-mentioned curable composition. The optical member of the present invention has a configuration in which it is sealed and bonded with the cured product of the above-mentioned curable composition, and therefore has excellent heat resistance and high light extraction efficiency.

[0142] The optical member of the present invention has excellent heat resistance and can maintain a high light transmittance even in a high-temperature environment. For example, the light transmittance of the optical member after heating at 120° C. for 300 hours (calculated by the following formula) is, for example, 70% or more, preferably 75% or more. Light transmittance maintenance rate = (Light transmittance of optical member after heating) / (Light transmittance of optical member before heating) x 100 EXAMPLES

[0143] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" representing a concentration means % by weight, and "ppm" representing a concentration means ppm by weight. It should be noted that Examples 3, 6, 9, and 12 are comparative examples.

[0144] Example 1 (Epoxidation process) 3000g of cyclohexenyl methyl methacrylate (hereinafter abbreviated as CHMA), 11000g of ethyl acetate, 1.2g of hydroquinone monomethyl ether, and 9.0g of sodium tripolyphosphate were added to a 20-liter SUS316 reactor equipped with a stirrer and a cooling jacket, and a mixed gas of oxygen / nitrogen (10 / 90% by volume) was blown into the reactor at 32N liters / hr from an insertion tube. Next, the reaction temperature was kept at 40°C, and 5166g of 30% peracetic acid solution was charged over 3 hours using a metering pump. After the charging was completed, the reaction was terminated after a further 5-hour aging. In this way, 19167g of reaction crude liquid containing 3,4-epoxycyclohexyl methyl methacrylate (hereinafter abbreviated as METHB) was obtained.

[0145] (Water washing process) A centrifugal extractor was operated at 4000 revolutions with a rotor having an outer diameter of 46 cm and an inner diameter of 25 mm. The crude reaction liquid containing METHB was fed from the light liquid inlet at a rate of 2108 g / min, and water was fed from the heavy liquid inlet at a rate of 3590 g / min. The light liquid was fed again to the same centrifugal extractor at a rate of 2108 g / min, and water was fed from the heavy liquid inlet at a rate of 3590 g / min. The light liquid was fed from the light liquid outlet at a rate of 1664 g / min, and the heavy liquid was fed from the heavy liquid outlet at a rate of 4034 g / min. The light liquid was fed again to the same centrifugal extractor at a rate of 2108 g / min, and water was fed from the heavy liquid inlet at a rate of 3590 g / min. The light liquid was fed from the light liquid outlet at a rate of 1877 g / min, and the heavy liquid was fed from the heavy liquid outlet at a rate of 3821 g / min. The concentrations of acetic acid and peracetic acid in the light liquid were 400 ppm and 150 ppm, respectively.

[0146] (Alkaline neutralization process) 3000 g of the light liquid thus obtained was charged into a 15-liter SUS316 treatment tank equipped with a stirrer and a cooling jacket, and 3000 g of a 1% NaOH aqueous solution was charged thereto and stirred for 1 hour while maintaining the temperature at 10° C. The residual peracetic acid concentration in the obtained crude liquid was 100 ppm or less.

[0147] (Desolvation process) Next, 0.16 g of hydroquinone monomethyl ether was added to 2790 g of this light liquid, and the first stage of desolvation was carried out using a SUS Smith-type thin-film evaporator. The operating conditions were a heating temperature of 60°C and a pressure of 150 mmHg, and a mixed gas of oxygen / nitrogen was blown in at 32 L / Hr from the bottom liquid discharge line. The second stage of desolvation was carried out on this bottom liquid under conditions of a heating temperature of 60°C and a pressure of 40 mmHg, and a mixed gas of oxygen / nitrogen (10 / 90% by volume) was blown in at 32 N L / Hr from the bottom liquid discharge line. The amount of the obtained bottom liquid was 538 g. The composition of the bottom liquid was examined by gas chromatography analysis, and it was found to be METHB 96.4%. The polymer content was found to be 0.01% by HT (heptane test).

[0148] (Low boiling process) 0.03% of polymerization inhibitor (N-nitroso-N,N-diphenylamine) was added to the METHB (purity 96.4%) obtained by the above method. This was continuously fed at a flow rate of 100 parts by weight / Hr to the 10th plate from the bottom of a 20-plate perforated plate column (tower diameter 50 mm) (low boiling point removal distillation column), and low boiling point removal distillation was carried out under the conditions of a top pressure of 0.1 mmHg, a top temperature of 80°C, a bottom temperature of 100°C, a heating temperature of 120°C, and a reflux ratio of 3. The flow rate of the bottom product was 90 parts by weight / Hr, and the flow rate of the overhead distillate was 10 parts by weight / Hr.

[0149] (High boiling process) The bottoms liquid obtained in the low boiling point removal step was continuously supplied to the 10th plate from the bottom of a 20-plate perforated tray tower (tower diameter 50 mm) (high boiling point removal distillation tower) at a flow rate of 100 parts by weight / Hr, and high boiling point removal distillation was carried out under conditions of a top pressure of 0.1 mmHg, a top temperature of 80°C, a bottom temperature of 110°C, a heating temperature of 130°C, and a reflux ratio of 3. The flow rate of the bottoms liquid was 10 parts by weight / Hr, and the flow rate of the overhead distillate was 90 parts by weight / Hr. The overhead distillate was recovered to obtain an alicyclic epoxy compound product 1.

[0150] Example 2 An alicyclic epoxy compound product 2 was obtained in the same manner as in Example 1, except that the reflux ratio of the low boiler removal distillation column was 1 and the reflux ratio of the high boiler removal distillation column was 1.

[0151] Example 3 An alicyclic epoxy compound product 3 was obtained in the same manner as in Example 1, except that the bottom product of the solvent removal step was charged into the fifth plate from the bottom of a perforated plate tower (tower diameter 50 mm) having an actual number of 10 plates (low boiling point removal distillation tower), and then the bottom product of the low boiling point removal distillation tower was charged into the fifth plate from the bottom of a perforated plate tower (tower diameter 50 mm) having an actual number of 10 plates (high boiling point removal distillation tower).

[0152] Comparative Example 1 An alicyclic epoxy compound product 4 was obtained in the same manner as in Example 1, except that the bottom product of the solvent removal step was charged into the second-from-the-bottom plate of a 5-actual-plate perforated tray tower (tower diameter 50 mm) (low-boiling-component removal distillation tower), and then the bottom product of the low-boiling-component removal distillation tower was charged into the second-from-the-bottom plate of a 5-actual-plate perforated tray tower (tower diameter 50 mm) (high-boiling-component removal distillation tower).

[0153] Comparative Example 2 Alicyclic epoxy compound product 5 was obtained in the same manner as in Example 1, except that the bottom product of the solvent removal step was charged to the fifth plate from the bottom of a 10-plate perforated column (tower diameter 50 mm) (low boiling point removal distillation column) and subjected to low boiling point removal distillation under conditions of a top temperature of 110°C, a bottom temperature of 140°C, and a heating temperature of 160°C, and subsequently the bottom product of the low boiling point removal distillation column was charged to the fifth plate from the bottom of a 10-plate perforated column (tower diameter 50 mm) (high boiling point removal distillation column) and subjected to high boiling point removal distillation under conditions of a top temperature of 110°C, a bottom temperature of 150°C, and a heating temperature of 170°C.

[0154] (Evaluation of alicyclic epoxy compound products) (1) Purity and impurity content For each of the alicyclic epoxy compound products obtained in the Examples and Comparative Examples, the purity of 3,4-epoxycyclohexylmethyl methacrylate [compound represented by formula (i)], and the contents of the compound represented by formula (a) [=compound (a)], the compound represented by formula (b) [=compound (b)], the compound represented by formula (c) [=compound (c)], and the compound represented by formula (d) [=compound (d)] were measured using a gas chromatograph under the conditions described below, and calculated in terms of area %. <Measurement conditions> Measuring device: Product name "GC-2014", manufactured by Shimadzu Corporation Column packing material: (15% PEG-20M) UniportHPS Column size: Length 2.1m x inner diameter 3.2mmφ Column temperature: 100°C → (heating at 10°C / min) → 210°C (held for 29 min) Detector:TCD

[0155] (2) Coloring degree The degree of coloration of each of the alicyclic epoxy compound products obtained in the Examples and Comparative Examples was evaluated by determining the Hazen color number (APHA).

[0156] (3) Storage stability The Hazen color number (APHA) of each of the alicyclic epoxy compound products obtained in the Examples and Comparative Examples was measured after storage at 30°C for one month, and the increase rate of the Hazen color number (APHA) (Hazen index after storage for one month / Hazen index immediately after production) was calculated, and the storage stability of each of the alicyclic epoxy compound products was evaluated according to the following criteria. ○: Less than 2 times ×: 2 times or more

[0157] The evaluation results of the alicyclic epoxy compound products obtained in the examples and comparative examples are shown in Table 1.

[0158] [Table 1]

[0159] Examples 4 to 12, Comparative Examples 3 to 8 The components were mixed according to the formulations (unit: parts by weight) shown in Tables 2 to 4 below, stirred using a planetary stirring device (product name "Awatori Rentaro AR-250", manufactured by Thinky Corporation), and then degassed to obtain curable compositions.

[0160] (Evaluation of Cured Product of Curable Composition) Each curable composition was filled into a mold and heated in a resin curing oven at a predetermined temperature for a predetermined time to obtain a cured product, and the glass transition temperature and transparency of the obtained cured product were evaluated by the following methods. Note that the curing conditions during curing were as follows. Examples 4 to 6, Comparative Examples 3 to 4: 120°C x 5 hours Examples 7 to 9, Comparative Examples 5 to 6: 80°C x 2 hours, and then 140°C x 2 hours Examples 10 to 12, Comparative Examples 7 to 8: 80°C x 2 hours, then 110°C x 3 hours

[0161] (1) Glass transition temperature (Tg) of the cured product The glass transition temperature of the cured product was determined under the following conditions. <Measurement conditions> Sample: Length 4mm x Width 5mm x Thickness 10mm Measurement equipment: Thermomechanical measurement equipment (TMA), product name "TMA / SS6000", manufactured by Seiko Instruments Inc. Measurement mode: Compression (penetration), constant load measurement Measurement temperature: 25℃ to 300℃ Heating rate: 5℃ / min

[0162] (2) Transparency of the cured product The light transmittance (thickness direction; % T) of light with a wavelength of 400 nm of the cured product (thickness: 3 mm) was measured using a spectrophotometer (product name "UV-2400", manufactured by Shimadzu Corporation).

[0163] (3) Overall Judgment Regarding Examples 4 to 6 and Comparative Examples 3 to 4 ○: Tg is 70°C or higher and transparency is 70% or higher ×: Tg is less than 70° C. or transparency is less than 70%. Regarding Examples 7 to 9 and Comparative Examples 5 to 6 ○: Tg is 60°C or higher and transparency is 70% or higher ×: Tg is less than 60°C or transparency is less than 70% Regarding Examples 10 to 12 and Comparative Examples 7 to 8 ○: Tg is 140°C or higher and transparency is 90% or higher ×: Tg is less than 140°C or transparency is less than 90%

[0164] (Evaluation of optical semiconductor devices) Each curable composition was poured into an optical semiconductor lead frame (InGaN element, 3.5 mm x 2.8 mm) and then heated in an oven at 120°C for 5 hours to obtain an optical semiconductor device in which an optical semiconductor element was encapsulated with a cured product of the curable composition (see Figure 1). The brightness and heat resistance of the obtained optical semiconductor device were evaluated.

[0165] (1) Brightness rating The brightness (lumen: lm) of the optical semiconductor device was measured by measuring the total luminous flux of the optical semiconductor device using a total luminous flux measuring device (product name "Multispectral Radiation Measurement System OL771", manufactured by Optronic Laboratories).

[0166] (2) Heat resistance evaluation The heat resistance of the optical semiconductor device was evaluated by subjecting the optical semiconductor device to heat treatment (aging) at 120° C. for 300 hours and calculating the light transmittance retention rate from the following formula, which was used as an index of heat resistance. Retention rate of light transmittance (%)=(light transmittance of optical semiconductor device after heat treatment / light transmittance of optical semiconductor device before heat treatment)×100

[0167] (3) Overall Judgment Regarding Examples 4 to 6 and Comparative Examples 3 to 4 ○: Brightness is 0.60lm or more and heat resistance is 70% or more ×: Brightness is less than 0.60lm or heat resistance is less than 70%. Regarding Examples 7 to 9 and Comparative Examples 5 to 6 ○: Brightness is 0.60lm or more and heat resistance is 70% or more ×: Brightness is less than 0.60lm or heat resistance is less than 70%. Regarding Examples 10 to 12 and Comparative Examples 7 to 8 ○: Brightness is 0.70lm or more and heat resistance is 80% or more ×: Brightness is less than 0.70lm or heat resistance is less than 80%.

[0168] (Evaluation of coating agents) Each of the curable compositions was used as a coating agent, and the reactivity thereof was evaluated by the following method.

[0169] (1) Reactivity (gel time) The reactivity of each curable composition (coating agent) was measured using a gel time measuring device (product name "No. 153 Gel Time Tester (Magnetic Type)" manufactured by Yasuda Seiki Seisakusho Co., Ltd.). Note that in Examples 4 to 6 and Comparative Examples 3 to 4, the reactivity (curability; gel time) was evaluated when heated at 120°C, and in Examples 7 to 12 and Comparative Examples 5 to 8, the reactivity (curability; gel time) was evaluated when heated at 80°C.

[0170] (2) Overall Judgment Regarding Examples 4 to 6 and Comparative Examples 3 to 4 ○: 120℃ gel time is within 2400 seconds ×: Gel time at 120°C exceeds 2400 seconds Regarding Examples 7 to 9 and Comparative Examples 5 to 6 ○: 80℃ gel time is within 2000 seconds ×: Gel time at 80℃ exceeds 2000 seconds Regarding Examples 10 to 12 and Comparative Examples 7 to 8 ○: 80℃ gel time is within 900 seconds ×: Gel time at 80℃ exceeds 900 seconds

[0171] Tables 2 to 4 show the evaluation results of the cured products of the above curable compositions, the photosemiconductor devices obtained using the above curable compositions, and the coating agents using the above curable compositions.

[0172] [Table 2]

[0173] [Table 3]

[0174] [Table 4]

[0175] The abbreviations in the table are explained below. MH-700: Hardener, 4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 70 / 30, product name "Rikacid MH-700", manufactured by New Japan Chemical Co., Ltd. 18X: Curing accelerator, special amine, product name "U-CAT 18X", manufactured by San-Apro Co., Ltd. SI-100L: Curing catalyst (thermal cationic polymerization initiator), product name "San-Aid SI-100L", manufactured by Sanshin Chemical Industry Co., Ltd. Perbutyl O: Curing catalyst (radical polymerization initiator) [Explanation of symbols]

[0176] 1 Reflector 2. Encapsulating materials for optical semiconductor elements 3 Bonding Wire 4. Optical semiconductor elements 5 Die bonding material 6 Metal wiring

Claims

1. An alicyclic epoxy compound product having a purity of 3,4-epoxycyclohexylmethyl methacrylate of 99.90 to 99.96% by weight, a total content of a compound represented by the following formula (a) and a compound represented by the following formula (b) of 0.02 to 0.05% by weight, and a Hazen color scale of 5 to 7. 【Chemistry 1】

2. The alicyclic epoxy compound product according to claim 1, wherein the total content of the compound represented by formula (a), the compound represented by formula (b), and the compound represented by the following formula (c) is 0.03 to 0.07% by weight: 【Chemistry 2】

3. The alicyclic epoxy compound product according to claim 1 or 2, wherein the total content of the compound represented by formula (a), the compound represented by formula (b), the compound represented by formula (c), and the compound represented by the following formula (d) is 0.04 to 0.10% by weight. 【Chemistry 3】

4. A curable composition comprising the cycloaliphatic epoxy compound product according to any one of claims 1 to 3.

5. The curable composition of claim 4 further comprising a curing agent and a curing accelerator.

6. The curable composition of claim 4 further comprising a curing catalyst.

7. A cured product of the curable composition according to any one of claims 4 to 6.

8. A sealant comprising the curable composition according to any one of claims 4 to 6.

9. An adhesive comprising the curable composition according to any one of claims 4 to 6.

10. A coating agent comprising the curable composition according to any one of claims 4 to 6.

11. An optical member comprising a member made of the cured product according to claim 7.

Images