JP2012211240A - Method of manufacturing epoxy compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing an epoxy compound in which a quarternary ammonium salt contained in the epoxy compound obtained by oxidizing a compound having a carbon-carbon double bond by using an oxidizing agent under the presence of the quarternary ammonium salt is efficiently removed to manufacture the epoxy compound excellent in thermal stability.SOLUTION: The method of manufacturing an epoxy compound is characterized as follows. The remaining quarternary ammonium salt in the epoxy compound is removed by using a montmorillonite-based material. In this case, the montmorillonite-based material whose pH of the suspension when dispersing in water is less than 7 (acidity) is used as a montmorillonite-based material, the epoxy resin is processed by the montmorillonite-based material, and then is washed by an aqueous acid.

Description

  The present invention relates to a method for producing an epoxy compound. More specifically, the present invention relates to a method for producing an epoxy compound containing less catalyst residue.

  Epoxy compounds (resins) have excellent physical properties such as electrical insulation, high heat resistance, moisture resistance, and dimensional stability. Semiconductor encapsulants, printed circuit boards, build-up boards, electronic components such as resist inks, and conductive pastes Conductive adhesives and other adhesives, liquid sealing materials such as underfill, liquid crystal sealing materials, flexible substrate coverlays, build-up adhesive films, composite matrixes, paints, photoresist materials, developer materials Etc. are widely used. Among these, in the field of electronic materials such as semiconductors and printed wiring boards, demands for higher performance of sealing materials and substrate materials are increasing along with technological innovation in these fields. In order to meet these demands, it is desirable that the epoxy compound (resin) is of high purity. However, in the production of the epoxy compound (resin), impurities such as halogens and metals are mixed in and remain, thereby reducing the performance. End up.

  Epoxy compounds (resins) are generally produced by the reaction of phenols, epichlorohydrin, and alkali metal oxides. The epoxy compounds (resins) produced by this method are hydrolyzable by-produced by the reaction. Chlorine compounds are included as impurities. When this epoxy compound (resin) containing a large amount of hydrolyzable chlorine compound is used as an underfill material, the hydrolyzable chlorine compound is decomposed and chlorine ions are decomposed when exposed to severe conditions such as high temperature and high humidity. It is known that a phenomenon occurs in which the wiring metal (semiconductor bonding portion) is corroded, and the long-term reliability of the semiconductor package is adversely affected. Therefore, as a sealing material for semiconductor devices, a method of oxidizing a carbon-carbon double bond of a compound having a carbon-carbon double bond by using an oxidizing agent is examined instead of a method using epichlorohydrin. . One example is a method of obtaining an epoxy compound by introducing an allyl group into a phenol (synthesizes allyl ether) and then oxidizing the allyl group with hydrogen peroxide.

  However, since hydrogen peroxide itself has a weak oxidizing power, it is necessary to perform an oxidation reaction using a metal catalyst or a phase transfer catalyst in combination. At that time, if the catalyst remains after the reaction, the oxirane (epoxy) ring is opened, leading to a problem that the thermal stability of the epoxy compound (resin) is lowered and the performance of the cured product is lowered.

  Thus, some studies on catalyst removal have been made. In Patent Document 1, a carbon-carbon double bond of a compound having a cyclohexene carboxyl ester structure having a carbon-carbon double bond in an alicyclic skeleton is oxidized using hydrogen peroxide, a quaternary ammonium salt and heteropolyphosphoric acid. However, it is disclosed that a quaternary ammonium salt is adsorbed with a smectite-based material. Patent Document 2 discloses that a polymer having an olefinic double bond is epoxidized with hydrogen peroxide, a tungstic acid catalyst, and a quaternary ammonium salt and then contacted with a basic substance. .

JP 2010-70481 A JP 2002-371113 A

  However, the compound having a cyclohexene carboxyl ester structure disclosed in Patent Document 1 is a low-molecular compound having no so-called repeating unit, and the present inventor performs the treatment disclosed in Patent Document 1 with a molecular weight distribution. When applied to a novolac compound, there was a problem that the water separation after the adsorption treatment had poor separation between the organic layer and the aqueous layer and was not efficient. Patent Document 2 describes only the remaining amount of tungstic acid and does not describe the remaining amount of quaternary ammonium salt. This method is insufficient because the quaternary ammonium salt is not sufficiently removed.

  The present invention efficiently converts a quaternary ammonium salt contained in an epoxy compound obtained by oxidizing a compound having a carbon-carbon double bond using a oxidant in the presence of a quaternary ammonium salt as a phase transfer catalyst. The present invention provides a method for producing an epoxy compound that is well removed and excellent in thermal stability.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have included a specific treatment for an epoxy compound obtained by using a quaternary ammonium salt as a phase transfer catalyst. It has been found that quaternary ammonium salts can be efficiently removed, and the present invention has been completed. That is, the present invention includes the following embodiments.

[1] A first step of synthesizing an epoxy compound by oxidizing a compound having a carbon-carbon double bond using an oxidizing agent in the presence of a quaternary ammonium salt, and the first step. A second step of removing a quaternary ammonium salt remaining in the epoxy compound by using a montmorillonite-based material, wherein in the second step, as a montmorillonite-based material, A method for producing an epoxy compound comprising a step of using a montmorillonite-based material having a pH of less than 7 when dispersed, or washing with an acidic aqueous solution after treating with a montmorillonite-based material.
[2] The method for producing an epoxy compound according to [1], wherein the montmorillonite-based substance is acidic clay or activated clay.
[3] The method for producing an epoxy compound according to [1] or [2], wherein the epoxy compound is a compound having a repeating unit.
[4] The method for producing an epoxy compound according to [3], wherein the epoxy compound is an epoxy compound having a number average molecular weight of 500 to 1200.
[5] The method for producing an epoxy compound according to any one of [1] to [4], wherein the compound having a carbon-carbon double bond is a phenol novolac polyallyl ether compound.
[6] The method for producing an epoxy compound according to any one of [1] to [5], wherein the oxidizing agent is hydrogen peroxide.
[7] The method for producing an epoxy compound according to any one of [1] to [6], wherein the quaternary ammonium salt is quaternary ammonium hydrogen sulfate or quaternary ammonium methyl sulfate.
[8] The method for producing an epoxy compound according to any one of [1] to [7], wherein a tungstic acid compound and a phosphorus compound are further used as a catalyst in the first step.
[9] The tungstic acid compound is at least one selected from the group consisting of tungstic acid, tungsten trioxide, tungsten trisulfide, phosphotungstic acid, potassium tungstate dihydrate, and sodium tungstate dihydrate. The method for producing an epoxy compound according to [8], which is characterized in that it exists.
[10] The phosphorus compound is at least one selected from the group consisting of phosphoric acid, polyphosphoric acid, pyrophosphoric acid and aminomethylphosphonic acid, and sodium and potassium salts thereof [8] or [8] 9] The manufacturing method of the epoxy compound as described in 9].

  According to the method for producing an epoxy compound of the present invention, an epoxy compound having few catalyst residues and excellent in thermal stability can be obtained. As a result, it is useful for electrical / electronic material applications such as semiconductor encapsulants that require heat resistance.

  The method for producing an epoxy compound of the present invention comprises a first step of synthesizing an epoxy compound by oxidizing a compound having a carbon-carbon double bond using an oxidizing agent in the presence of a quaternary ammonium salt, A second step of removing the quaternary ammonium salt remaining in the epoxy compound obtained in one step using a montmorillonite-based material, and in the second step, dispersed in water as a montmorillonite-based material A step of using a montmorillonite-based material having a pH of the suspension of less than 7 (acidic) or treating with a montmorillonite-based material and then washing with an acidic aqueous solution is characterized.

[First step]
The first step in the method for producing an epoxy compound of the present invention is to oxidize a compound having a carbon-carbon double bond using an oxidizing agent in the presence of a quaternary ammonium salt as a phase transfer catalyst, that is, carbon-carbon. This is a step of obtaining an epoxy compound by oxidizing (epoxidizing) a double bond.

  The compound having a carbon-carbon double bond used in the first step of the present invention is not particularly limited, and may be a compound having one carbon-carbon double bond in the molecule, or a carbon-carbon double bond. It may be a compound having two or more. Moreover, any of an aliphatic compound, a compound having an alicyclic skeleton, and an aromatic compound may be used, or a low molecular compound (monomer) or a compound having a repeating unit (polymer, oligomer) may be used. The effect of the present invention is more exhibited when a compound having a repeating unit, for example, a compound having a plurality of carbon-carbon double bonds having a molecular weight distribution which is a mixture of a plurality of molecules having different numbers of repeating units is used. Examples of such a compound are obtained by allylating the hydroxyl group of an allyl ether compound or a phenol novolak compound obtained by allylating the hydroxyl group of a bisphenol A type or bisphenol F type and hydrogenated bisphenol compound. An allyl ether compound is mentioned. Examples of the phenol compound that can be used as a raw material for the phenol novolac compound include phenol, orthocresol, naphthol, bisphenol A, and bisphenol F.

  As the phenol novolac compound, known compounds obtained by addition condensation of phenols and formaldehydes under acidic conditions can be used. The number average molecular weight of the phenol novolac compound is preferably 450 to 1000. When the number average molecular weight of the phenol novolac compound is less than 450, the heat resistance cannot be sufficiently satisfied, and when it exceeds 1000, the melt viscosity becomes high and the workability is deteriorated.

  The allyl etherification of the known phenol compound is a known method in which an allyl halide such as allyl bromide, an allyl carboxylate such as allyl acetate, an allylating agent such as allyl carbonate, allyl alcohol and the like are reacted with the hydroxyl group of the phenol compound. You can use the method. Among the phenol compounds derived from these phenol compounds, phenol novolac compounds such as phenol novolak and ortho cresol novolak which are raw materials for general-purpose epoxy resins having high heat resistance and polyfunctional structure are preferable, and ortho is more preferable. It is a cresol novolac compound.

  The oxidizing agent used in the first step of the present invention can be applied as long as it can oxidize (epoxidize) the carbon-carbon double bond of the compound having a carbon-carbon double bond. From the viewpoint of cost, it is preferable to use hydrogen peroxide. As the hydrogen peroxide source, an aqueous hydrogen peroxide solution can be suitably used, and various concentrations can be used. From the viewpoint of reaction efficiency, volumetric efficiency, and safety, about 10 to about 80% by mass. It is preferable to use an aqueous hydrogen peroxide solution, and it is more preferable to use an aqueous hydrogen peroxide solution of about 30 to about 60% by mass. Although there is no restriction | limiting about the usage-amount of hydrogen peroxide, Generally about 0.8-about 10 equivalent with respect to the carbon-carbon double bond of the compound which has a carbon-carbon double bond, Preferably about 1- A range of about 3 equivalents.

  In the first step of the present invention, a quaternary ammonium salt is used as a phase transfer catalyst. Examples of quaternary ammonium salts include tetrapentyl ammonium chloride, tetrahexyl ammonium chloride, tetraheptyl ammonium chloride, tetraoctyl ammonium chloride, dilauryl dimethyl ammonium chloride, methyl triheptyl ammonium chloride, methyl trioctyl ammonium chloride, bromide. Quaternary ammonium chloride such as tetrapentylammonium, tetrahexylammonium bromide, tetraheptylammonium bromide, tetraoctylammonium bromide, methyltriheptylammonium bromide, methyltrioctylammonium bromide, dilauryldimethylammonium bromide, etc. Quaternary ammonium bromide, tetrapentylammonium hydrogensulfate, tetrahexylammonium hydrogensulfate, tetraheptylammonium hydrogensulfate, sulfur Quaternary ammonium hydrogen sulfate such as tetraoctylammonium hydrogen, methyltriheptylammonium hydrogensulfate, methyltrioctylammonium hydrogensulfate, dilauryldimethylammonium hydrogensulfate, methyltetrapentylammonium sulfate, methyltetrahexylammonium sulfate, methyltetraheptyl sulfate Examples thereof include quaternary ammonium sulfate such as ammonium, methyltetraoctylammonium sulfate, methylmethyltriheptylammonium sulfate, methylmethyltrioctylammonium sulfate, and methyldilauryldimethylammonium sulfate. Among these compounds, quaternary ammonium hydrogen sulfate and quaternary ammonium methyl sulfate are preferable because they do not contain halogen. Tetrahexyl ammonium hydrogen sulfate, tetraoctyl ammonium hydrogen sulfate, methyl trioctyl ammonium hydrogen sulfate, methyl methyl trioctyl ammonium sulfate Etc. are more preferable in terms of reactivity. These compounds may be used alone or in combination of two or more. The amount used is preferably from about 0.0001 to about 10 mol%, more preferably from about 0.01 to about 5 mol%, based on the carbon-carbon double bond of the compound having a carbon-carbon double bond. It is a range.

  In the first step of the present invention, various known methods using a quaternary ammonium salt as a phase transfer catalyst can be applied, but it is preferable to use a tungstic acid compound and a phosphorus compound in combination. Tungstic acid-based compounds are compounds that generate tungstate anions in water, such as tungstic acid, tungsten trioxide, tungsten trisulfide, phosphotungstic acid, potassium tungstate dihydrate, sodium tungstate dihydrate. Thing etc. are mentioned. Among these compounds, tungstic acid, tungsten trioxide, phosphotungstic acid, sodium tungstate dihydrate and the like are preferable. These catalysts may be used alone or in combination of two or more. The amount used is preferably from about 0.0001 to about 20 mol%, more preferably from about 0.01 to about 10 mol%, based on the carbon-carbon double bond of the compound having a carbon-carbon double bond. It is a range.

  Examples of the phosphorus compound include phosphoric acid, polyphosphoric acid, pyrophosphoric acid, aminomethylphosphonic acid, and sodium salts and potassium salts thereof. Among these compounds, phosphoric acid and aminomethylphosphonic acid are preferable. These compounds may be used alone or in combination of two or more. The amount used is preferably from about 0.0001 to about 20 mol%, more preferably from about 0.01 to about 10 mol%, based on the carbon-carbon double bond of the compound having a carbon-carbon double bond. It is a range.

  In the first step of the present invention, it is preferable to use an organic solvent from the viewpoint of reducing the viscosity of the reaction solution and improving the reactivity. Examples of the organic solvent include normal hexane, cyclohexane, toluene, xylene, methanol, ethanol, 2-propanol, 1,2-dimethoxyethane, ethyl acetate and the like. Among these, toluene, xylene, ethyl acetate and the like are preferable. These organic solvents may be used alone or in combination of two or more. The amount to be used is preferably in the range of about 10 to about 500% by mass, more preferably about 50 to 200% by mass, based on the compound having a carbon-carbon double bond.

  The reaction temperature of the oxidation (epoxidation) reaction, which is the first step of the present invention, is not particularly limited, but is usually in the range of about 30 to about 100 ° C, preferably in the range of about 50 to about 90 ° C. . The reaction time is not particularly limited, but is usually in the range of 1 hour to 48 hours, preferably 3 hours to 24 hours.

  When the epoxy compound obtained in the first step of the present invention has a small number average molecular weight, the epoxidation reaction proceeds sufficiently, and there is no problem with the separation between the organic layer and the aqueous layer during washing. On the other hand, when the number average molecular weight is large, the reaction result of epoxidation is lowered and it is difficult to obtain a sufficiently epoxidized compound. Therefore, it is preferable that the number average molecular weight of an epoxy compound exists in the range of 500-1200, More preferably, it is 600-1000.

  After completion of the epoxidation reaction, a base is added to the reaction solution, and the aqueous layer is neutralized to pH 6-7. In this case, examples of the base to be added include alkali metal hydroxides and alkali metal carbonates. Preferred are sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and the like.

  Thereafter, the organic layer and the aqueous layer are separated, and excess hydrogen peroxide is reduced. Examples of the reducing agent used include sodium sulfite, sodium bisulfite, and sodium thiosulfate. The amount of the reducing agent used is preferably in the range of about 0.1 to about 5 equivalents, more preferably about 1 to about 3 equivalents, with respect to the excess hydrogen peroxide.

[Second step]
The 2nd process in the manufacturing method of the epoxy compound of this invention is a process of removing the quaternary ammonium salt which remains in the epoxy compound obtained at the 1st process using a montmorillonite type substance. In this second step, as a first aspect, as a montmorillonite-based material, a method of treating with a montmorillonite-based material showing a numerical value (acidic) of a suspension having a pH smaller than 7 when dispersed in water; As a second embodiment, there is a method of washing with an acidic aqueous solution after treating with a montmorillonite-based substance.

  In the first embodiment, a montmorillonite-based substance is added to the organic layer subjected to the reduction treatment to adsorb the quaternary ammonium salt remaining in the epoxy compound. By this treatment, the quaternary ammonium salt can be efficiently removed including the subsequent water washing step. The montmorillonite-based material that can be used in the first embodiment is not particularly limited as long as the main component is montmorillonite and the pH of the suspension when dispersed in water exhibits a value (acidity) smaller than 7. , Mainly acidic clay and activated clay. Acid clay is a white clay mineral mainly composed of montmorillonite, and when dispersed in water, the pH of the suspension is less than 7, that is, it is acidic. Activated clay is obtained by treating acid clay with acid, and when dispersed in water, the suspension similarly exhibits acidity. Examples of the acid clay include Mizuka Ace # 20, Mizuka Ace # 400 (manufactured by Mizusawa Chemical Co., Ltd.), Nikkanite S-200, Nikkanite A-36 (manufactured by Toshin Kasei Co., Ltd.), and examples of the activated clay include Galeon Earth. V2, Galeon Earth NVZ (made by Mizusawa Chemical Co., Ltd.), activated white clay SA-35, activated white clay T (made by Toshin Kasei Co., Ltd.), and the like. In the case where a montmorillonite-based substance having a pH of suspension of less than 7 when dispersed in water, that is, acidic, is used, the next operation is merely to wash away water-soluble impurities by washing with water.

  On the other hand, when using other montmorillonite substances whose pH of the suspension does not become less than 7 when dispersed in water, it is necessary to wash with an acidic aqueous solution after treating with the second aspect, ie, the montmorillonite substance. There is. Examples of other montmorillonite materials include galeonite # 036 (manufactured by Mizusawa Chemical Co., Ltd.), Kunipia F (manufactured by Kunimine Kogyo Co., Ltd.), and the like.

  The amount of the montmorillonite-based material used is preferably about 0.1 to about 20 times (mass ratio), more preferably about 0.5 to about the quaternary ammonium salt remaining after the reaction in any embodiment. The amount is 10 times (mass ratio). The number of times of processing may be divided into once or a plurality of times.

  When the montmorillonite-based substance is acidic, the next operation is only to wash away water-soluble impurities by washing with water. However, you may wash | clean with acidic aqueous solution. On the other hand, when a montmorillonite-based substance whose pH of the suspension does not become less than 7 when dispersed in water is used, the separation property between the organic layer and the aqueous layer at the time of water washing is not good. As a result, separability is improved and workability can be improved. In that case, examples of the acidic substance used include hydrochloric acid, sulfuric acid, nitric acid, carbonic acid, phosphoric acid, and boric acid. The amount of water used may be such that the pH of the aqueous layer after washing is closer to the acidic side than neutral, and is preferably 0.01% to 5% with respect to the mass of the washing water.

EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited to these Examples.
The analysis and evaluation methods for the epoxy compounds used in the examples of the present invention are as follows.

<Remaining amount of quaternary ammonium salt>
The residual amount of the quaternary ammonium salt was measured by 1H-NMR using a 400 MHz nuclear magnetic resonance apparatus AVANCE III 400 manufactured by Bruker BioSpin Corporation using deuterated chloroform as a measurement solvent.

<Average molecular weight>
The average molecular weight of the epoxy compound was measured using JASCO Corporation high performance liquid chromatograph LC-2000Plus series. The measurement conditions were as follows: Column: KF-802 (manufactured by Showa Denko KK), oven temperature: 40 ° C., eluent: tetrahydrofuran, flow rate: 1.0 mL / min, detector: RI2031, number average in terms of polystyrene The molecular weight was determined.

<Epoxy equivalent>
The epoxy equivalent was determined according to JIS-K7236. A sample is weighed in an amount of 0.1 to 0.2 g, placed in an Erlenmeyer flask, and then dissolved by adding 10 mL of dichloromethane. Next, 20 mL of acetic acid is added, followed by 10 mL of tetraethylammonium bromide solution (100 g of tetraethylammonium bromide dissolved in 400 mL of acetic acid). One or two drops of crystal violet indicator were added to this solution and titrated with a 0.1 mol / L perchloric acid acetic acid solution. Based on the titration result, the epoxy equivalent was determined according to the following formula.
Epoxy equivalent (g / eq) = (1000 × m) / {(V ₁ −V ₀ ) × c}
m: Mass of the sample (g)
V ₀ : Amount of perchloric acid acetic acid solution consumed for titration to the end point in the blank test (mL)
V ₁ : Amount of perchloric acid acetic acid solution consumed for titration to the end point (mL)
c: Concentration of perchloric acid acetic acid solution (0.1 mol / L)

<Thermal stability evaluation>
In order to evaluate the thermal stability of the purified epoxy compound, a heat treatment was performed at 100 ° C. for 24 hours. Thereafter, the melt viscosity at 100 ° C. was measured using a Phison MCR301 manufactured by Anton Paar at a shear rate of 100 seconds ⁻¹ and a measurement time of 200 seconds. The melt viscosity at 100 ° C. before the heat treatment was 2990 mPa · s.

Synthesis Example 1 (Synthesis of cresol novolac polyallyl ether)
In a 2000 mL eggplant-shaped flask, orthocresol novolak resin CRG-951 (manufactured by Showa Denko KK, hydroxyl group equivalent 118) 200.0 g, 50% water content 5% -Pd / C-STD type (N Chemchem Co., Ltd.) 3.61 g (0.847 mmol), triphenylphosphine (Hokuko Chemical Co., Ltd.) 2.22 g (8.47 mmol), potassium carbonate (Asahi Glass Co., Ltd.) 234 g (1.69 mol), allyl acetate ( 187 g (1.86 mol) manufactured by Showa Denko KK and 200 g of isopropanol were added and reacted at 85 ° C. for 8 hours in a nitrogen atmosphere. After the reaction, a part is sampled, diluted with ethyl acetate, washed with pure water until the washing solution becomes neutral, then isopropanol and ethyl acetate are distilled off, and the hydroxyl value is measured according to JIS-K0070, It was confirmed that hydroxyl groups were almost consumed. Thereafter, 400 g of toluene was added to the reaction solution, Pd / C and the precipitated solid were removed by filtration, and isopropanol and toluene were distilled off by an evaporator to obtain 260 g of polyallyl ether of cresol novolac resin. It was 157 as a result of measuring the iodine value of this polyallyl ether by the neutralization titration method based on JIS-K0070.

Example 1
A solution prepared by previously dissolving 16.7 g (50.8 mmol) of sodium tungstate in 20.0 g of pure water and 7.68 g (100 mmol) of 45% hydrogen peroxide aqueous solution was prepared.
In a 2000 mL three-necked flask equipped with a dropping funnel and a Dimroth condenser, 200 g of cresol novolac polyallyl ether, 133 g of toluene, 5.88 g (12.6 mmol) of methyl trioctylammonium hydrogensulfate, 4.96 g (50.8 mmol) of phosphoric acid , And a pre-dissolved tungstic acid solution were added, and the bath temperature was heated to 70 ° C. When the bath temperature reached 70 ° C., 143 g (1.89 mol) of an aqueous hydrogen peroxide solution was added dropwise over 1 hour, and then the reaction was continued for 7 hours at a bath temperature of 70 ° C. After 7 hours, the reaction solution was cooled to room temperature, toluene (100 mL) was added, and 1N aqueous sodium hydroxide solution was added to adjust the pH to 6. After transferring to a separatory funnel and separating the aqueous layer, the toluene layer was washed with pure water (100 g). Thereafter, the remaining peroxide was treated with a 1% sodium sulfite aqueous solution (100 g), and further washed with pure water (100 g).
The washed toluene layer was transferred to a 1 L separable flask, Mizuka Ace # 20 (acid white clay manufactured by Mizusawa Chemical Co., Ltd.) (17.6 g) was added, and the mixture was stirred for 1 hour, and then Mizuka Ace # 20 was filtered off. did. The same treatment was repeated twice for the filtrate using the same amount of Mizuka Ace # 20, and then the filtrate was washed 3 times with pure water (100 g). In this water washing step, the separation time of the organic layer and the aqueous layer required 30 minutes each time. Thereafter, toluene in the organic layer was distilled off to obtain 200 g of an epoxy compound (cresol novolac polyglycidyl ether). When the epoxy equivalent of the epoxy compound was measured, it was 195 g / eq, and when the number average molecular weight was measured by GPC, it was Mn = 822. When the residual amount of the quaternary ammonium salt was confirmed by 1H-NMR, it was 560 ppm. The melt viscosity after heat treatment at 100 ° C. for 24 hours was 3020 mPa · s. Mizuka Ace # 20 had a pH of 5.0 as measured at 20 ° C. of a suspension in which 0.5 g was dispersed in 10 g of pure water.

Example 2
The same operation was performed using the same amount of Galleon Earth V2 (activated clay manufactured by Mizusawa Chemical Co., Ltd.) instead of Mizuka Ace # 20 used in Example 1. The separation time in the water washing step after removing the quaternary ammonium salt required 40 minutes each time. The residual amount of ammonium salt in the obtained epoxy compound was 1680 ppm. Moreover, the melt viscosity after heat-processing at 100 degreeC for 24 hours was 3110 mPa * s. In addition, Galleon Earth V2 had a pH of 3.5 when a suspension in which 0.5 g was dispersed in 10 g of pure water was measured at 20 ° C.

Example 3
Quaternary ammonium salt removal was performed using the same amount of Kunipia F (Kunmine Industrial Co., Ltd. montmorillonite) instead of Mizuka Ace # 20 used in Example 1. Thereafter, it was washed with a 3% phosphoric acid solution (100 g) instead of pure water. The separation time of the washing step required 40 minutes each time, and the pH of the aqueous layer after washing was 5.6. Furthermore, pure water washing (100 g) was repeated twice. The residual amount of ammonium salt in the obtained epoxy compound was 1260 ppm. Moreover, the melt viscosity after heat-processing at 100 degreeC for 24 hours was 3090 mPa * s. The pH of Kunipia F measured at 20 ° C. in a suspension of 0.5 g in 10 g of pure water was 10.2.

Comparative Example 1
In Example 1, the quaternary ammonium salt removal treatment was not performed, but toluene was distilled off to obtain an epoxy compound. The residual amount of ammonium salt in the epoxy compound was 28000 ppm. Moreover, when it heat-processed at 100 degreeC for 24 hours, the epoxy compound hardened | cured and melt viscosity measurement was not able to be performed.

Comparative Example 2
A similar operation was performed using the same amount of Kunipia F (Kunmine Industrial Co., Ltd. Montmorillonite) instead of Mizuka Ace # 20 used in Example 1. The separation time in the water washing step after removing the quaternary ammonium salt required 2 hours each time. The residual amount of ammonium salt in the obtained epoxy compound was 1260 ppm. Moreover, the melt viscosity after heat-processing at 100 degreeC for 24 hours was 3090 mPa * s.

Comparative Example 3
The same operation was carried out using the same amount of Somasif ME100 (Mica from Corp Chemical Co.) instead of Mizuka Ace # 20 used in Example 1. The separation time of the water washing step after removing the quaternary ammonium salt required 2.5 hours. The remaining amount of ammonium salt in the obtained epoxy compound was 1,080 ppm. Moreover, the melt viscosity after a heat test was 7230 mPa * s.

  The present invention can be suitably used for producing an epoxy compound having high thermal stability. The epoxy compound produced by the method of the present invention is useful for electrical / electronic material applications such as semiconductor encapsulants that require heat resistance.

Claims (10)

A first step of synthesizing an epoxy compound by oxidizing a compound having a carbon-carbon double bond with an oxidizing agent in the presence of a quaternary ammonium salt;
A second step of removing a quaternary ammonium salt remaining in the epoxy compound obtained in the first step by using a montmorillonite-based substance,
In the second step, as the montmorillonite-based material, a step of using a montmorillonite-based material whose pH of the suspension when dispersed in water is less than 7 or treating with the montmorillonite-based material and then washing with an acidic aqueous solution The manufacturing method of the epoxy compound characterized by including.   The method for producing an epoxy compound according to claim 1, wherein the montmorillonite-based substance is acidic clay or activated clay.   The method for producing an epoxy compound according to claim 1, wherein the epoxy compound is a compound having a repeating unit.   The said epoxy compound is an epoxy compound of the number average molecular weights 500-1200, The manufacturing method of the epoxy compound of Claim 3 characterized by the above-mentioned.   The method for producing an epoxy compound according to any one of claims 1 to 4, wherein the compound having a carbon-carbon double bond is a phenol novolac polyallyl ether compound.   The said oxidizing agent is hydrogen peroxide, The manufacturing method of the epoxy compound of any one of Claims 1-5 characterized by the above-mentioned.   The method for producing an epoxy compound according to any one of claims 1 to 6, wherein the quaternary ammonium salt is quaternary ammonium hydrogen sulfate or quaternary ammonium methyl sulfate.   The method for producing an epoxy compound according to any one of claims 1 to 7, wherein a tungstic acid compound and a phosphorus compound are further used as a catalyst in the first step.   The tungstic acid-based compound is at least one selected from the group consisting of tungstic acid, tungsten trioxide, tungsten trisulfide, phosphotungstic acid, potassium tungstate dihydrate, and sodium tungstate dihydrate. The manufacturing method of the epoxy compound of Claim 8 characterized by the above-mentioned.   10. The phosphorus compound according to claim 8 or 9, wherein the phosphorus compound is at least one selected from the group consisting of phosphoric acid, polyphosphoric acid, pyrophosphoric acid and aminomethylphosphonic acid, and sodium salts and potassium salts thereof. A method for producing an epoxy compound.