Highly soluble modified epoxy resin composition

Abstract

An epoxy resin composition in a liquid or solid state having excellent solubility and having high preservation stability. A modified epoxy resin composition including: Compound A containing tris-(2,3-epoxypropyl)-isocyanurate having 1 to 3 glycidyl group(s) in a molecule substituted with a functional group(s) of Formula (1): ##STR00001##
in which R.sup.1 and R.sup.2 are each independently an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, a heterocyclic group; or a halogenated derivative, an aminated derivative, or a nitrated derivative of these groups; and Compound B containing tris-(2,3-epoxypropyl)-isocyanurate, wherein tris-(2,3-epoxypropyl)-isocyanurate of Compound A before the substitution and tris-(2,3-epoxypropyl)-isocyanurate of Compound B comprise 2% by mass to 15% by mass of -type tris-(2,3-epoxypropyl)-isocyanurate and a remaining percentage of -type tris-(2,3-epoxypropyl)-isocyanurate based on a total mass of Compound A before the substitution and Compound B.

Claims

1. A modified epoxy resin composition comprising: Compound A containing tris-(2,3-epoxypropyl)-isocyanurate having 1 to 3 glycidyl group(s) in a molecule substituted with a functional group(s) of Formula (1): ##STR00004## wherein R.sup.1 and R.sup.2 are each independently an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, a heterocyclic group; or a halogenated derivative, an aminated derivative, or a nitrated derivative of these groups; and Compound B containing tris-(2,3-epoxypropyl)-isocyanurate, wherein: a molar ratio of Compound A:Compound B is 90:10 to 30:70; tris-(2,3-epoxypropyl)-isocyanurate of Compound A before the substitution and tris-(2,3-epoxypropyl)-isocyanurate of Compound B comprise 2% by mass to 15% by mass of -type tris-(2,3-epoxypropyl)-isocyanurate and a remaining percentage of -type tris-(2,3-epoxypropyl)-isocyanurate based on a total mass of tris-(2,3-epoxypropyl)-isocyanurate of Compound A before the substitution and tris-(2,3-epoxypropyl)-isocyanurate of Compound B; and the composition is formed by: extracting -type tris-(2,3-epoxypropyl)-isocyanurate from a crystalline body containing -type tris-(2,3-epoxypropyl)-isocyanurate and -type tris-(2,3-epoxypropyl)-isocyanurate using a solvent having about 20 times increased solubility with -type tris-(2,3-epoxypropyl)-isocyanurate versus -type tris-(2,3-epoxypropyl)-isocyanurate, to obtain a tris-(2,3-epoxypropyl)-isocyanurate crystalline body having an increased content ratio of -type tris-(2,3-epoxypropyl)-isocyanurate, and reacting the crystalline body with an acid anhydride of Formula (2): ##STR00005## wherein R.sup.1 and R.sup.2 have the same meaning as those in Formula (1).

2. The modified epoxy resin composition according to claim 1, wherein tris-(2,3-epoxypropyl)-isocyanurate of Compound A before the substitution and tris-(2,3-epoxypropyl)-isocyanurate of Compound B comprise 2% by mass to 10% by mass of -type tris-(2,3-epoxypropyl)-isocyanurate and a remaining percentage of -type tris-(2,3-epoxypropyl)-isocyanurate based on a total mass of tris-(2,3-epoxypropyl)-isocyanurate of Compound A before the substitution and tris-(2,3-epoxypropyl)-isocyanurate of Compound B.

3. The modified epoxy resin composition according to claim 1, wherein the solvent is methyl ethyl ketone, acetone, acetonitrile, ethyl acetate, or epichlorohydrin.

4. The modified epoxy resin composition according to claim 1, wherein the composition is soluble in a 83 wt % mixture of the composition in acid anhydride for at least 1 week at 25 C.

5. The modified epoxy resin composition according to claim 1, wherein the composition is soluble in a 83 wt % mixture of the composition in acid anhydride for at least 40 days at 25 C.

6. The modified epoxy resin composition according to claim 1, wherein the molar ratio of Compound A:Compound B is 61.8:38.2 to 30:70.

7. The modified epoxy resin composition according to claim 1, wherein the molar ratio of Compound A:Compound B is 48.2:51.8 to 30:70.

8. A method for manufacturing a modified epoxy resin composition, the method comprising: Step (i): separating -type tris-(2,3-epoxypropyl)-isocyanurate contained in a tris-(2,3-epoxypropyl)-isocyanurate solution from the solution as a solid, and obtaining a crystalline body having an increased content ratio of -type tris-(2,3-epoxypropyl)-isocyanurate from the solution; Step (ii): obtaining a tris-(2,3-epoxypropyl)-isocyanurate crystalline body having a further increased content ratio of -type tris-(2,3-epoxypropyl)-isocyanurate from the crystalline body obtained in Step (i) by extracting -type tris-(2,3-epoxypropyl)-isocyanurate with a solvent having about 20 times increased solubility with -type tris-(2,3-epoxypropyl)-isocyanurate versus -type tris-(2,3-epoxypropyl)-isocyanurate; and Step (iii): reacting the tris-(2,3-epoxypropyl)-isocyanurate crystalline body obtained in Step (ii) with an acid anhydride, provided that a molar ratio of (glycidyl groups):(acid anhydrides) is 1:0.05 to 0.5, in order to obtain the modified epoxy resin composition, wherein the modified epoxy resin composition comprises: Compound A containing tris-(2,3-epoxypropyl)-isocyanurate having 1 to 3 glycidyl group(s) in a molecule substituted with a functional group(s) of Formula (1): ##STR00006## wherein, R.sup.1 and R.sup.2 are each independently an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, a heterocyclic group; or a halogenated derivative, an aminated derivative, or a nitrated derivative of these groups; and Compound B containing tris-(2,3-epoxypropyl)-isocyanurate, wherein tris-(2,3-epoxypropyl)-isocyanurate of Compound A before the substitution and tris-(2,3-epoxypropyl)-isocyanurate of Compound B comprise 2% by mass to 15% by mass of -type tris-(2,3-epoxypropyl)-isocyanurate and a remaining percentage of -type tris-(2,3-epoxypropyl)-isocyanurate based on a total mass of tris-(2,3-epoxypropyl)-isocyanurate of Compound A before the substitution and tris-(2,3-epoxypropyl)-isocyanurate of Compound B.

9. The method according to claim 8, wherein the solvent used for extracting -type tris-(2,3-epoxypropyl)-isocyanurate in Step (ii) is methyl ethyl ketone, acetone, methanol, ethanol, or isopropanol (2-propanol).

Description

EXAMPLES

(1) The following are devices used for analyzing samples.

(2) HPLC

(3) Device: LC-20A system manufactured by SHIMADZU Corporation (analysis of compositions of -type and -type)

(4) GC

(5) Device: GC-2010 system manufactured by SHIMADZU Corporation (analysis of compositions after modifications)

(6) Viscosity measurement: E-type viscometer (VISCONIC ED) manufactured by TOKIMEC INC.

(7) Transmittance measurement: UV-Vis-NIR spectrophotometer (UV-3600) manufactured by SHIMADZU Corporation

(8) Bending test: Precision universal tester (AGS-X series) manufactured by SHIMADZU Corporation

(9) Coefficient of linear expansion, glass transition temperature measurement: Thermomechanical analyzer (TMA Q400) manufactured by TA Instruments

(10) <Method for Measuring Proportion of -type and -type of Tris-(2,3-epoxypropyl)-isocyanurate>

(11) HPLC was performed by using a commercially available column for optical resolution whose product name is CHIRALPAK AS-3 (manufactured by Daicel Corporation (0.46 cm diameter10 cm long)) and n-hexane/ethanol (60/40 w/w) as an eluant, in the condition of 40 C. for a column temperature and 0.4 ml/minute for flux. The crystals in a sample were dissolved in acetonitrile, and the solution was further diluted with the eluant. The diluted solution was injected into HPLC to be separated by chromatography. The -type tris-(2,3-epoxypropyl)-isocyanurate is eluted at 11.1 minutes and 13.2 minutes; and the -type tris-(2,3-epoxypropyl)-isocyanurate is eluted at 11.7 minutes and 12.4 minutes. The proportion of -type or -type in the total crystals was calculated by the area ratio of each of the peaks.

(12) <Method for Measuring Proportion of Tris-(2,3-epoxypropyl)-isocyanurate and Modified Product Thereof>

(13) GC was performed by using a commercially available column whose product name is HP-5 (manufactured by Agilent Technologies, Inc.) (30 m0.32 mm0.25 m), in the condition of 250 C. for an injector temperature, 300 C. for a detector temperature, 40 C. (5 minutes) >20 C./minute >300 C. (12 minutes) for oven temperatures, a carrier gas: nitrogen, 89.1 kPa for gas pressure, 74.4 ml/minute for total flux, 3.4 ml/minute for column flux, and 50 cm/second for linear velocity. Samples were dissolved in acetonitrile for measurements. Tris-(2,3-epoxypropyl)-isocyanurate was detected at 16.5 minutes, one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate was detected at 18.4 minutes, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate were detected at 20.9 minutes, and three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate were detected at 25.1 minutes. The proportion of tris-(2,3-epoxypropyl)-isocyanurate and each of the modified products thereof was calculated by the area ratio of each of the peaks.

Synthesis Example 1

(14) To a reaction flask having an inner volume of 2 liters and equipped with a stirrer, 30 g of water, 5.5 g of tetramethylammonium chloride, 1,388 g (15 mol) of epichlorohydrin, and 129 g (1 mol) of isocyanuric acid were placed to form a reaction mixture. Next, the reaction mixture in the flask was heated with stirring to elevate a temperature. When the temperature of the reaction mixture reached 89 C., the reaction mixture started to be boiled under atmospheric pressure; however, the reaction mixture was continued to be heated. Generated steam was cooled in a condenser, all of liquefied epichlorohydrin was sequentially refluxed in the flask, and liquefied water was discharged out of the flask. These processes were performed to be continued for five hours to allow the temperature of the reaction mixture to reach 120 C. Then heating was stopped at this time point, and the reaction mixture was cooled to obtain a reaction product whose temperature was 45 C. Unreacted isocyanuric acid was not detected in this product.

(15) Next, as the entire reaction product in the flask was kept at 50 C., dropping of 256 g (3.2 mol as NaOH) of a 50% by mass sodium hydroxide aqueous solution to the reaction product was started under 100 mmHg of reduced pressure to form a reaction mixture. At the same time, water and epichlorohydrin were allowed to be evaporated from the reaction mixture with stirring vigorously. As gradually increasing the degree of reduced pressure, steam was cooled in a condenser, all of liquefied epichlorohydrin was sequentially refluxed in the flask, and liquefied water was discharged out of the flask. As continuing these processes, dropping was stopped when the degree of reduced pressure reached 60 mmHg to obtain slurry containing precipitated sodium chloride. Six hours have passed from the beginning to ending of the dropping. During the six hours, the stirred reaction mixture was kept homogeneous, while it became clouded by precipitated sodium chloride. According to a liquid chromatography analysis, a content of the compound having a 2-hydroxy-3-chlorpropyl group in the obtained slurry was 1% or less.

(16) The obtained tris-(2,3-epoxypropyl)-isocyanurate was (in crystalline bodies, the mass ratio of crystals: crystals=75:25).

Synthesis Example 2

(17) 80.0 kg (269 mol) of the highly pure tris-(2,3-epoxypropyl)-isocyanurate manufactured in Synthesis Example 1 and 680 kg of acetone were mixed, and stirred at 9 C. After that, crystals were filtered to obtain a filtrate containing a high proportion of the -type. The filtrate was vacuum concentrated at 40 C., 243 kg of methanol was added thereto, and the mixture was cooled to 20 C. After that, the mixture was filtered, and the obtained crystals were vacuum dried to obtain 37.3 kg (125 mol) of tris-(2,3-epoxypropyl)-isocyanurate (in crystalline bodies, the mass ratio of crystals: crystals=98:2).

Synthesis Example 3

(18) 5.0 g (17 mmol) of the highly pure tris-(2,3-epoxypropyl)-isocyanurate manufactured in Synthesis Example 1 and 42.5 g of epichlorohydrin were mixed, and stirred at 6 C. After that, crystals were filtered to obtain a filtrate containing a high proportion of the -type. 785 g of methanol was added thereto, and the mixture was cooled to 78 C. After that, the mixture was filtered, and the obtained crystals were vacuum dried to obtain 3.2 g (11 mmol) of tris-(2,3-epoxypropyl)-isocyanurate (in crystalline bodies, the mass ratio of crystals: crystals=92:8).

Synthesis Example 4

(19) 42.5 g of tris-(2,3-epoxypropyl)-isocyanurate (the mass ratio of crystals: crystals=98:2) manufactured in Synthesis Example 2, 11.0 g of acetonitrile, 7.63 g (the molar ratio of glycidyl groups:acid anhydrides=1:0.13) of propionic anhydride, and 23.8 mg of ethyl triethyl phosphonium bromide were mixed, and stirred at 100 C. for 2 hours. After that, the mixture was vacuum concentrated to obtain 47.8 g of a liquid modified epoxy resin composition.

(20) As a result of a GC analysis, a molar ratio of one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, and tris-(2,3-epoxypropyl)-isocyanurate (non-adduct) in the product was 39.7:8.1:0.4:51.8 (a molar ratio of Compound A:Compound B=48.2:51.8). The epoxy equivalent was 138.1 g/eq, viscosity was 4, 090 mPa.Math.s at 60 C. This epoxy resin composition was designated as (i-1).

Synthesis Example 5

(21) 42.5 g of tris-(2,3-epoxypropyl)-isocyanurate (the mass ratio of crystals: crystals=98:2) manufactured in Synthesis Example 2, 11.0 g of acetonitrile, 11.2 g (the molar ratio of glycidyl groups:acid anhydrides=1:0.20) of propionic anhydride, and 23.8 mg of ethyl triethyl phosphonium bromide were mixed, and stirred at 100 C. for 4 hours. After that, the mixture was vacuum concentrated to obtain 52.4 g of a liquid modified epoxy resin composition.

(22) As a result of a GC analysis, a molar ratio of one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, and tris-(2,3-epoxypropyl)-isocyanurate (non-adduct) in the product was 46.0:14.5:1.3:38.2 (a molar ratio of Compound A:Compound B=61.8:38.2). The epoxy equivalent was 157.2 g/eq, viscosity was 3,344 mPa.Math.s at 60 C. This epoxy resin composition was designated as (i-2).

Synthesis Example 6

(23) 85.0 g of tris-(2,3-epoxypropyl)-isocyanurate (the mass ratio of crystals: crystals=98:2) manufactured in Synthesis Example 2, 46.8 g of toluene, 29.8 g (the molar ratio of glycidyl groups:acid anhydrides=1:0.27) of propionic anhydride, and 48.6 mg of ethyl triethyl phosphonium bromide were mixed, and stirred at 100 C. for 8 hours, and 120 C. for 3 hours. After that, the mixture was vacuum concentrated to obtain 112.8 g of a liquid modified epoxy resin composition.

(24) As a result of a GC analysis, a molar ratio of one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, and tris-(2,3-epoxypropyl)-isocyanurate (non-adduct) in the product was 52.5:22.3:2.2:23.1 (a molar ratio of Compound A:Compound B=76.9:23.1). The epoxy equivalent was 177.4 g/eq, viscosity was 2,610 mPa.Math.s at 60 C. This epoxy resin composition was designated as (i-3).

Synthesis Example 7

(25) 2.70 g of tris-(2,3-epoxypropyl)-isocyanurate (the mass ratio of crystals: crystals=92:8) manufactured in Synthesis Example 3, 0.71 g of acetonitrile, 0.49 g (the molar ratio of glycidyl groups:acid anhydrides=1:0.13) of propionic anhydride, and 1.5 mg of ethyl triethyl phosphonium bromide were mixed, and stirred at 110 C. for 6 hours. After that, the mixture was vacuum concentrated to obtain 2.97 g of a liquid modified epoxy resin composition.

(26) As a result of a GC analysis, a molar ratio of one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, and tris-(2,3-epoxypropyl)-isocyanurate (non-adduct) in the product was 40.2:5.0:0.2:54.6 (a molar ratio of Compound A:Compound B=45.4:54.6). The epoxy equivalent was 134.4 g/eq, viscosity was 4, 280 mPa.Math.s at 60 C. This epoxy resin composition was designated as (i-4).

Reference Example 1

(27) 42.5 g of tris-(2,3-epoxypropyl)-isocyanurate (the mass ratio of -types:-types=75:25) manufactured in Synthesis Example 1, 11.0 g of acetonitrile, 7.63 g (the molar ratio of glycidyl groups:acid anhydrides=1:0.13) of propionic anhydride, and 23.8 mg of ethyl triethyl phosphonium bromide were mixed, and stirred at 100 C. for 2 hours. After that, the mixture was vacuum concentrated to obtain 48.3 g of a liquid modified epoxy resin composition.

(28) As a result of a GC analysis, a molar ratio of one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, and tris-(2,3-epoxypropyl)-isocyanurate (non-adduct) in the product was 37.7:7.9:0.6:53.8 (a molar ratio of Compound A:Compound B=46.2:53.8). The epoxy equivalent was 136.4 g/eq, viscosity was 4, 640 mPa.Math.s at 60 C. This epoxy resin composition was designated as (i-5).

Reference Example 2

(29) 42.5 g of tris-(2,3-epoxypropyl)-isocyanurate (the mass ratio of -types:-types=75:25) manufactured in Synthesis Example 1, 11.0 g of acetonitrile, 11.2 g (the molar ratio of glycidyl groups:acid anhydrides=1:0.20) of propionic anhydride, and 23.8 mg of ethyl triethyl phosphonium bromide were mixed, and stirred at 100 C. for 4 hours. After that, the mixture was vacuum concentrated to obtain 52.1 g of a liquid modified epoxy resin composition.

(30) As a result of a GC analysis, a molar ratio of one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, and tris-(2,3-epoxypropyl)-isocyanurate (non-adduct) in the product was 45.2:14.3:1.5:39.1 (a molar ratio of Compound A:Compound B=60.9:39.1). The epoxy equivalent was 157.9 g/eq, viscosity was 3,748 mPa.Math.s at 60 C. This epoxy resin composition was designated as (i-6).

Reference Example 3

(31) 85.0 g of tris-(2,3-epoxypropyl)-isocyanurate (the mass ratio of -types:-types=75:25) manufactured in Synthesis Example 1, 46.8 g of toluene, 29.8 g (the molar ratio of glycidyl groups:acid anhydrides=1:0.27) of propionic anhydride, and 48.6 mg of ethyl triethyl phosphonium bromide were mixed, and stirred at 100 C. for 8 hours and 120 C. for 1 hour. After that, the mixture was vacuum concentrated to obtain 113.3 g of a liquid modified epoxy resin composition.

(32) As a result of a GC analysis, a molar ratio of one adduct of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, two adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, three adducts of propionic anhydride to tris-(2,3-epoxypropyl)-isocyanurate, and tris-(2,3-epoxypropyl)-isocyanurate (non-adduct) in the product was 51.0:22.9:2.6:23.5 (a molar ratio of Compound A:Compound B=76.5:23.5). The epoxy equivalent was 181.8 g/eq, viscosity was 2,681 mPa.Math.s at 60 C. This epoxy resin composition was designated as (i-7).

(33) (Solubility Test to Solvent)

(34) To 100 g of each of the solvents, each of the epoxy resin compositions was added with each of the amounts shown below, and the mixtures were left at 25 C. for 1 week or longer. After that, the mixtures were visually inspected for existence of precipitated crystals. The results are shown in Tables 1 to 5, as the case where none of crystals were observed is (), and the case where crystals were precipitated is (). Note that () means that the solubility test was not conducted. In Tables, PGME refers to propylene glycol monomethyl ether, PGMEA refers to propylene glycol monomethyl ether acetate, and MEK refers to methyl ethyl ketone.

(35) TABLE-US-00001 TABLE 1 Example 1 Example 2 Example 3 Example 4 Example 5 Amount of Epoxy Resin Composition Epoxy Resin (i-1) (i-1) (i-1) (i-1) (i-1) Composition Solvent (g/solvent Ethyl 100 g) PGME PGMEA MEK Acetate Toluene 25 x 20 x x x 15 x x 10 x 5 x 3 1

(36) TABLE-US-00002 TABLE 2 Exam- Exam- Exam- Exam- Exam- ple 6 ple 7 ple 8 ple 9 ple 10 Amount of Epoxy Resin Composition Epoxy Resin (i-4) (i-4) (i-4) (i-4) (i-4) Composition Solvent (g/solvent Ethyl 100 g) PGME PGMEA MEK Acetate Toluene 20 x x x x 10 x x x 5 3 x 1

(37) TABLE-US-00003 TABLE 3 Compar- Compar- Compar- Compar- Compar- ative ative ative ative ative Example 1 Example 2 Example 3 Example 4 Example 5 Amount of Epoxy Resin Composition Epoxy Resin (i-5) (i-5) (i-5) (i-5) (i-5) Composition Solvent (g/solvent Ethyl 100 g) PGME PGMEA MEK Acetate Toluene 10 x x x x x 5 x x x x x 3 x x x 1 x x x

(38) TABLE-US-00004 TABLE 4 Exam- Exam- Exam- Exam- Exam- ple 11 ple 12 ple 13 ple 14 ple 15 Amount of Epoxy Resin Composition Epoxy Resin (i-3) (i-3) (i-3) (i-3) (i-3) Composition Solvent (g/solvent Ethyl 100 g) PGME PGMEA MEK Acetate Toluene 40 x x x 35 x x 30 x 25 x 20 x x 15 x x 10 5

(39) TABLE-US-00005 TABLE 5 Compar- Compar- Compar- Compar- Compar- ative ative ative ative ative Exam- Exam- Exam- Exam- Exam- ple 6 ple 7 ple 8 ple 9 ple 10 Amount of Epoxy Resin Composition Epoxy Resin (i-7) (i-7) (i-7) (i-7) (i-7) Composition Solvent (g/solvent Ethyl 100 g) PGME PGMEA MEK Acetate Toluene 25 x 20 x x x 15 x x x 10 x x 5 x 3

(40) In the epoxy resin composition (i-3) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=97:3 was modified, solubility was improved in any of the solvents compared to the epoxy resin composition (i-7) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=75:25 was modified.

(41) (Solubility Test to Acid Anhydride as Curing Agent)

Example 16

(42) To 4.0 g of the epoxy resin composition (i-1), 4.8 g of a compound having the product name of RIKACID MH-700 (manufactured by New Japan Chemical Co., Ltd., a liquid mixture containing hexahydro-4-methylphthalic anhydride and hexahydro phthalic anhydride in the mass ratio of 70/30) was added, and mixed and defoamed in a device for stirring and defoaming (the product name: Awatori Rentaro, manufactured by THINKY Corporation) to prepare a composition. Ingredients were confirmed to be colorless and transparent, and to be dissolved uniformly. After that, the composition was left at 25 C. for 40 days, and then the appearance of the composition was visually confirmed.

Example 17

(43) To 0.40 g of the epoxy resin composition (i-4), 0.48 g of a compound having the product name of RIKACID MH-700 (manufactured by New Japan Chemical Co., Ltd., a liquid mixture containing hexahydro-4-methylphthalic anhydride and hexahydro phthalic anhydride in the mass ratio of 70/30) was added, and mixed and defoamed in a device for stirring and defoaming (the product name: Awatori Rentaro, manufactured by THINKY Corporation) to prepare a composition. Ingredients were confirmed to be colorless and transparent, and to be dissolved uniformly. After that, the composition was left at 25 C. for 1 week, and then the appearance of the composition was visually confirmed.

Comparative Example 11

(44) To 4.0 g of the epoxy resin composition (i-5), 4.8 g of a compound having the product name of RIKACID MH-700 (manufactured by New Japan Chemical Co., Ltd., a liquid mixture containing hexahydro-4-methylphthalic anhydride and hexahydro phthalic anhydride in the mass ratio of 70/30) was added, and mixed and defoamed in a device for stirring and defoaming (the product name: Awatori Rentaro, manufactured by THINKY Corporation) to prepare a composition. Ingredients were confirmed to be colorless and transparent, and to be dissolved uniformly. After that, the composition was left at 25 C. for 40 days, and then the appearance of the composition was visually confirmed.

(45) TABLE-US-00006 TABLE 6 Comparative Example 16 Example 17 Example 11 Epoxy Resin Composition (i-1) (i-4) (i-5) Curing Agent MH-700 MH-700 MH-700 Appearance Colorless and Colorless and Clouded Transparent Transparent

(46) The epoxy resin composition (i-1) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=97:3 was modified and the epoxy resin composition (i-4) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=92:8 was modified were uniformly dissolved in curing agents after they were left; however, in the epoxy resin composition (i-5) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=75:25 was modified, crystals were precipitated and the solution became clouded because of low solubility of the epoxy resin composition (i-5).

(47) [Preparation of Heat Cured Product]

Example 18

(48) To 20.0 g of the epoxy resin composition (i-1), 23.9 g of an acid anhydride curing agent RIKACID MH700 (the product name, manufactured by New Japan Chemical Co., Ltd., the ingredient is a mixture in which hexahydro-4-methylphthalic anhydride and hexahydro phthalic anhydride are mixed in the molar ratio of 70:30) and 0.2 g of a curing accelerator HISHICOLIN PX-4ET (the product name, manufactured by The Nippon Synthetic Chemical Industry Co., Ltd., the ingredient is tetrabutylphosphonium diethyl phosphorodithioate) were added, and mixed and defoamed in a device for stirring and defoaming (the product name: Awatori Rentaro, manufactured by THINKY Corporation) to prepare a composition.

(49) The mixture was poured between glass plates sandwiching a 3 mm silicone rubber, in which the glass plates were treated with a releasing agent (the treatment was performed at 150 C. for 1 hour with the releasing agent SR-2410 (the product name) manufactured by Dow Corning Toray Co., Ltd.), and curing was performed such that preliminary curing was performed at 100 C. for 2 hours, and actual curing was performed at 150 C. for 5 hours.

Example 19

(50) 20.0 g of the epoxy resin composition (i-2), 21.0 g of RIKACID MH-700, and 0.20 g of HISHICOLIN PX-4ET were placed in the same manner as in the case of Example 18, and curing was performed.

Example 20

(51) 20.0 g of the epoxy resin composition (i-3), 18.6 g of RIKACID MH-700, and 0.20 g of HISHICOLIN PX-4ET were placed in the same manner as in the case of Example 18, and curing was performed.

Comparative Example 12

(52) 20.0 g of the epoxy resin composition (i-5), 24.2 g of RIKACID MH-700, and 0.20 g of HISHICOLIN PX-4ET were placed in the same manner as in the case of Example 18, and curing was performed.

Comparative Example 13

(53) 20.0 g of the epoxy resin composition (i-6), 20.9 g of RIKACID MH-700, and 0.20 g of HISHICOLIN PX-4ET were placed in the same manner as in the case of Example 18, and curing was performed.

Comparative Example 14

(54) 20.0 g of the epoxy resin composition (i-7), 18.1 g of RIKACID MH-700, and 0.20 g of HISHICOLIN PX-4ET were placed in the same manner as in the case of Example 18, and curing was performed.

(55) For the obtained cured product, a three-point bending test (bending strength and bending modulus of elasticity) was conducted, and transmittance, a glass transition temperature, and a coefficient of linear expansion of the product were measured.

(56) (Measurement of Bending Property)

(57) Bending Properties were measured with a universal testing machine according to JIS K-6911.

(58) The height and width of a test piece were measured, and the test piece was supported. Loads were applied on the center of the test piece with a pressure wedge, and a load by which the test piece was broken was measured to calculate a bending strength ().

(59) A bending strength : (MPa) {kgf/mm.sup.2}; P: a load when the test piece was broken (N) {kgf}; L: a distance between fulcra (mm); W: a width of the test piece (mm); and h: a height of the test piece (mm).
=(3PL)/(2Wh.sup.2)

(60) When F/Y is a slope on a linear portion on a load-deflection curve (N/mm) {kgf/mm}, bending modulus of elasticity (E): (MPa) {kgf/mm.sup.2} is
E=[L.sup.3/(4Wh.sup.3)][FLY]

(61) (Measurement of Transmittance)

(62) Transmittance at 400 nm was measured by using a spectrophotometer.

(63) (Measurement of Glass Transition Temperature (Tg))

(64) A thickness of the test piece was precisely measured, and an expansion and contraction method of TMA (thermo-mechanical analysis) was performed with a load of 0.05 N and a rate of temperature rise at 5 C./minute. Tangent lines were drawn on a curve before and after a glass transition point, and Tg was calculated from a intersecting point of the tangent lines.

(65) (Measurement of Coefficient of Linear Expansion)

(66) The coefficient of linear expansion was measured according to JIS K-6911. A thickness of the test piece was precisely measured, and an expansion and contraction method of TMA (thermo-mechanical analysis) was performed with a load of 0.05 N and a rate of temperature rise at 5 C./minute.

(67) The linear coefficient of expansion 1 was calculated as: an amount of change of the length from at 30 C. to at 80 C. (L1)/an initial length of the test piece (L)50=1.

(68) TABLE-US-00007 TABLE 7 Bending Coefficient Bending Modulus of Transmit- of Linear Strength Elasticity tance Tg Expansion MPa MPa % C. ppm/ C. Example 18 145 3778 90 168 77 Example 19 142 3594 87 161 79 Example 20 135 3428 86 152 93 Comparative 136 3802 89 172 78 Example 12 Comparative 135 3558 87 166 81 Example 13 Comparative 120 3407 86 151 93 Example 14

(69) The epoxy resin composition (i-1) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=97:3 was modified and the epoxy resin composition (i-5) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=75:25 was modified showed almost comparable curing characteristics. The epoxy resin composition (i-2) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=97:3 was modified and the epoxy resin composition (i-6) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=75:25 was modified showed almost comparable curing characteristics. The epoxy resin composition (i-3) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=97:3 was modified and the epoxy resin composition (i-7) in which tris-(2,3-epoxypropyl)-isocyanurate having the mass ratio of -types:-types=75:25 was modified showed almost comparable curing characteristics.

INDUSTRIAL APPLICABILITY

(70) As described above, the present invention can provide a liquid or solid epoxy resin composition having excellent solubility and high preservation stability, by modifying a crystalline epoxy resin.