Epoxy resin curable composition and adhesive including same

Abstract

Provided is an epoxy resin curable composition that cures quickly and has high hardness and exceptional color tone after curing. Provided is an epoxy resin curable composition containing an epoxy resin having two or more epoxy groups per molecule, a thiol compound having two or more thiol groups per molecule, an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group, the epoxy resin curable composition being characterized in that the molar ratio M1+2 / Me is 0.11-0.5 and the molar ratio M3 / Me is 0.005-0.1, where Me is the number of moles of epoxy groups included in the epoxy resin curable composition, M1+2 is the total number of moles of primary amino groups and secondary amino groups, and M3 is the number of moles of tertiary amino groups.

Description

Epoxy resin curable composition and adhesive containing same

[0001] The present invention relates to a curable epoxy resin composition that cures quickly and gives a cured product with high hardness and strong adhesive strength after curing, as well as excellent color tone.

[0002] Epoxy resins have been widely used as adhesives because of their excellent adhesive properties, chemical resistance, and physical properties. For applications requiring fast curing and high adhesive strength, a method of adding a thiol compound as a curing agent and an amine as a curing accelerator is known.

[0003] Numerous compounds containing terminal thiol groups that do not contain a polysulfide skeleton in the main chain have been reported as compounds capable of rapidly reacting thiol groups with epoxy groups (see, for example, Patent Document 1). Among these, compounds that have a polyether skeleton in the main chain and three or more thiol groups per molecule are widely available commercially as curing agents for epoxy resins that are both economical and safe. Examples of compounds that have a polyether skeleton in the main chain and three or more thiol groups per molecule include "Polythiol QE-340M" manufactured by Toray Fine Chemicals Co., Ltd., and "Capcure 3-800" and "GPM-800" manufactured by Gabriel Performance Products.

[0004] Amines widely used as curing accelerators for thiol groups and epoxy groups include tertiary amines such as 2,4,6-tris(dimethylaminomethyl)phenol (ANCAMINE K-54, manufactured by Evonik Corporation), N,N-dimethylpropylamine, and bis(2-dimethylaminoethyl)ether.

[0005] However, conventionally known epoxy resin curable compositions turn yellow and become colored when cured, which poses a problem when used in applications requiring near colorlessness and excellent color tone, such as adhesives for glass and decorative items.

[0006] Conventionally known colorless epoxy resin curable compositions have slow curing properties, making them unsuitable for applications requiring rapid curing, and have not always provided sufficient hardness or adhesive strength. Thus, it has been difficult for an epoxy resin curable composition comprising an epoxy resin, a thiol compound, and an amine compound to simultaneously achieve rapid curing, hardness, adhesive strength, and color tone.

[0007] Japanese Patent Application Publication No. 8-269203

[0008] The present invention provides a curable epoxy resin composition that cures quickly, has high hardness after curing, has strong adhesive strength, and is excellent in color tone.

[0009] The epoxy resin curable composition of the present invention is an epoxy resin curable composition containing an epoxy resin having two or more epoxy groups in one molecule, a thiol compound having two or more thiol groups in one molecule, an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group, wherein the number of moles of the epoxy groups contained in the epoxy resin curable composition is Me, and the total number of moles of the primary amino group and the secondary amino group is M. 1+2 When the number of moles of tertiary amino groups is M3, the molar ratio M 1+2 / Me is 0.11 to 0.5, and the molar ratio M3 / Me is 0.005 to 0.1.

[0010] The epoxy resin curable composition of the present invention cures quickly, has high hardness and strong adhesive strength after curing, and has excellent color tone.

[0011] When the epoxy resin curable composition of the present invention is used as an adhesive, it exhibits strong adhesive strength to various adherends such as metals and glass. This epoxy resin curable composition can be used as an adhesive, a sealant, a potting material, a coating agent, a resin modifier, etc.

[0012] In particular, the epoxy resin curable composition of the present invention has excellent color tone and is therefore ideal for use as an adhesive for glass, an adhesive for decorative items, an adhesive for watch parts, an adhesive for electrical and electronic applications, a potting material for electrical and electronic applications, and an adhesive for everyday carpentry.

[0013] The epoxy resin curable composition of the present invention contains an epoxy resin having two or more epoxy groups in one molecule, a thiol compound having two or more thiol groups in one molecule, an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group.

[0014] Examples of epoxy resins having two or more epoxy groups per molecule include epoxy resins obtained by adding epichlorohydrin to polyhydric phenols such as bisphenol A, bisphenol F, resorcinol, hydroquinone, pyrocatechol, 4,4-dihydroxybiphenyl, and 1,5-hydroxynaphthalene, epoxy resins obtained by adding epichlorohydrin to polyhydric alcohols such as ethylene glycol, propylene glycol, and glycerin, and epoxy resins obtained by adding epichlorohydrin to aromatic dicarboxylic acids such as hydroxybenzoic acid and phthalic acid, and polysulfide polymers having epoxy groups at their terminals (trade names "FLEP-50" and "FLEP-60," both manufactured by Toray Fine Chemicals Co., Ltd.). Epoxy resins having two or more epoxy groups per molecule are preferably liquid at room temperature from the viewpoints of workability and preventing poor mixing. Examples of epoxy resins having two or more epoxy groups in one molecule include jER-828 (trade name, manufactured by Mitsubishi Chemical Corporation), DER-331 (trade name, manufactured by Dow Chemical), jER-825 (trade name, manufactured by Mitsubishi Chemical Corporation), jER-827 (trade name, manufactured by Mitsubishi Chemical Corporation), jER-806 (trade name, manufactured by Mitsubishi Chemical Corporation), and jER-807 (trade name, manufactured by Mitsubishi Chemical Corporation).

[0015] The epoxy resin having two or more epoxy groups in one molecule preferably has an epoxy equivalent of 50 to 1000 g / eq, and more preferably has an epoxy equivalent of 100 to 300 g / eq.

[0016] Examples of thiol compounds containing two or more thiol groups in one molecule include ethylene glycol bis(3-mercaptopropionate), diethylene glycol bis(3-mercaptopropionate), tetraethylene glycol bis(3-mercaptopropionate), 1,2-propylene glycol bis(3-mercaptopropionate), diethylene glycol bis(3-mercaptobutyrate), 1,4-butanediol bis(3-mercaptopropionate ... 1,8-octanediol bis(3-mercaptobutyrate), 1,8-octanediol bis(3-mercaptopropionate), 1,8-octanediol bis(3-mercaptobutyrate), hexanediol bisthioglycolate, trimethylolpropane tris(3-mercaptopropionate), trimethylolpropane tris(3-mercaptobutyrate), trimethylolpropane tris(3-mercaptoisobutyrate), trimethylolpropane tris(2 ... propane tristhioglycolate, tris-[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, trimethylolethane tris(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptoisobutyrate), pentaerythritol tetrakis(2-mercaptoisobutyrate), dipentaerythritol hexakis( Examples of the thiol compounds include dipentaerythritol hexakis(3-mercaptopropionate), dipentaerythritol hexakis(2-mercaptopropionate), dipentaerythritol hexakis(3-mercaptobutyrate), dipentaerythritol hexakis(3-mercaptoisobutyrate), dipentaerythritol hexakis(2-mercaptoisobutyrate), pentaerythritol tetrakisthioglycolate, dipentaerythritol hexakisthioglycolate, and thiol compounds having a polyether moiety in the main chain.

[0017] The thiol compound preferably has three or more thiol groups in one molecule, and examples of such thiol compounds include trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptopropionate), trimethylolethane tris(3-mercaptobutyrate), and pentaerythritol tetrakis(3-mercaptoacetate).

[0018] A thiol compound containing two or more thiol groups per molecule preferably has a polyether moiety in the main chain and a thiol group on the carbon adjacent to the carbon bearing a hydroxyl group. Furthermore, the thiol compound preferably does not have a carbonyl group. The absence of a carbonyl group in a thiol compound is preferred because it inhibits hydrolysis of the cured product and improves water resistance.

[0019] The structure having a polyether moiety in the main chain is preferably represented by the following general formula (1), and the terminal thiol group is preferably represented by the following formula (2). (However, R 1 is a residue obtained by removing m hydrogen atoms from a polyamine or polyhydric alcohol having 10 or less carbon atoms, and R 2 is an alkylene group having 2 to 4 carbon atoms, n is an integer of 1 to 200, and m is an integer of 2 to 8.

[0020] In the general formula (1), R 1 is a residue obtained by removing m hydrogen atoms from a polyhydric amine or polyhydric alcohol having 10 or less carbon atoms. Examples of polyhydric amines or polyhydric alcohols having 10 or less carbon atoms include glycerin, trimethylolpropane, trimethylolethane, hexanetriol, diglycerin, pentaerythritol, triethanolamine, ethylenediamine, and sucrose. These polyhydric amines and polyhydric alcohols may be used alone or in combination. Among the above polyols, glycerin, trimethylolpropane, and trimethylolethane are particularly preferred.

[0021] In the general formula (1), R 2is an alkylene group having 2 to 4 carbon atoms. Examples of the alkylene group having 2 to 4 carbon atoms include ethylene, n-propylene, isopropylene, n-butylene, and isobutylene.

[0022] In the general formula (1), n ​​is an integer of 1 to 200, preferably an integer of 1 to 100. Furthermore, m is an integer of 2 to 8, preferably an integer of 2 to 5.

[0023] Examples of thiol compounds having the structures represented by the general formula (1) and formula (2) include "Polythiol QE-340M" manufactured by Toray Fine Chemicals Co., Ltd., and "Capcure3-800" and "GPM-800" manufactured by Gabriel Performance Products. These thiol compounds do not have a carbonyl group.

[0024] The thiol compound containing two or more thiol groups in one molecule preferably has at least one thiol group represented by the formula (2), and more preferably has two or more thiol groups. All of the thiol groups in the thiol compound may be contained as the structure represented by the formula (2).

[0025] The thiol compound containing two or more thiol groups in one molecule preferably has a thiol group content of 1 to 50% by mass, more preferably 5 to 20% by mass.

[0026] The phrase "the thiol compound does not have a carbonyl group" means that the thiol compound does not have a carbonyl group, a carboxy group, a thiocarboxy group, an aldehyde group, an ester bond, a thioester bond, an amide bond, or the like.

[0027] The amounts of the epoxy resin and thiol compound described above can be determined so that the molar ratio Mt / Me (the number of moles of thiol groups derived from the thiol compound Mt to the number of moles of epoxy groups derived from the epoxy resin Me present in the epoxy resin curable composition) is preferably 0.1 to 0.9, more preferably 0.2 to 0.8, even more preferably 0.2 to 0.7, and even more preferably 0.32 to 0.64. A molar ratio Mt / Me of 0.1 or greater is preferred because it accelerates curing. Furthermore, a molar ratio Mt / Me of 0.9 or less is preferred because it increases the Shore D hardness of the cured product.

[0028] The amount of thiol compound can be appropriately designed depending on the physical properties of the epoxy resin curable composition, and preferably satisfies the above-mentioned molar ratio Mt / Me relationship. For example, it is preferable to blend 50 to 150 parts by mass of thiol compound per 100 parts by mass of epoxy resin having two or more epoxy groups per molecule. When the amount of thiol compound is 50 to 150 parts by mass per 100 parts by mass of epoxy resin, the resulting epoxy resin curable composition cures quickly, the cured product has high hardness, and has sufficient adhesive strength. The amount of thiol compound per 100 parts by mass of epoxy resin is more preferably 60 to 120 parts by mass, and even more preferably 70 to 100 parts by mass.

[0029] The epoxy resin curable composition contains an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group. By containing at least two types of amine compounds, consisting of amine compound A and amine compound B, the epoxy resin curable composition can be cured quickly, have high hardness and strong adhesive strength after curing, and achieve excellent color tone. Amine compound A may have only primary amino groups derived from a primary amine, only secondary amino groups derived from a secondary amine, or may have primary amino groups derived from a primary amine and secondary amino groups derived from a secondary amine.

[0030] The amine compound A is preferably an aliphatic amine. Examples of aliphatic amines include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,5-diaminopentane, hexamethylenediamine, tetramethylenediamine, trimethylhexamethylenediamine, 2-methyl-1,5-diaminopentane, polyetherdiamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, bis(hexamethylene)triamine, N,N'-dimethylethylenediamine, and N,N-dimethyl-1,3-propanediamine. It is preferable that the amine compound A is not an aliphatic amine in which the amino group is composed solely of secondary amino groups. That is, it is preferable that the amine compound A has at least one primary amino group. It is also preferable that the amine compound A has no tertiary amino group.

[0031] More preferably, the amine compound A is an amine having two or more primary amino groups and / or two or more secondary amino groups in one molecule, but no tertiary amino group. Examples of the amine compound A include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,5-diaminopentane, hexamethylenediamine, tetramethylenediamine, trimethylhexamethylenediamine, 2-methyl-1,5-diaminopentane, polyetherdiamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, bis(hexamethylene)triamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, and bis(hexamethylene)triamine. More preferred examples of the amine having two or more amino groups in one molecule and no tertiary amino group in the molecule include ethylenediamine, diethylenetriamine, triethylenetetramine, 1,3-diaminopropane, and tetraethylenepentamine.

[0032] More preferably, the amine compound A has three or more primary amino groups and / or secondary amino groups per molecule. The amine having three or more amino groups per molecule is preferably diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, or bis(hexamethylene)triamine, and more preferably triethylenetetramine.

[0033] Amine compound A is particularly preferably a modified product made from an amine having three or more primary amino groups and / or secondary amino groups per molecule. Modified products made from amines having three or more amino groups per molecule are particularly preferably modified products of diethylenetriamine, triethylenetetramine, or tetraethylenepentamine, and more preferably modified products obtained by reacting the amino groups of triethylenetetramine with a mono- or polyepoxy compound. An example of a modified product made from an amine having three or more amino groups per molecule is "BB-AMINE 3138" manufactured by BB Resins SRL.

[0034] The modified product made from an amine having three or more amino groups in one molecule preferably has an amine value of 500 to 2500 KOHmg / g, more preferably 800 to 1700 KOHmg / g.

[0035] The amine compound B is an amine having a tertiary amino group derived from a tertiary amine. Examples of amine compound B include trimethylamine, benzyldimethylamine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethyl-1,3-diaminopropane, dimethylaniline, N,N-dimethyl-1,3-propanediamine, diazabicycloundecene, 2,4,6-tris(dimethylaminomethyl)phenol, ANCAMINE (registered trademark) K-54 (manufactured by Evonik), and N,N'-bis(3-(dimethylamine)propylurea). Amine compound B is preferably an amine having two or more tertiary amino groups derived from a tertiary amine. More preferably, it is an amine having no primary amino groups derived from a primary amine. Even more preferably, it is an amine having only tertiary amino groups derived from a tertiary amine, and no primary amino groups derived from a primary amine or secondary amino groups derived from a secondary amine. By including amine compound B, the hardness of the cured product can be increased, and the adhesive strength can be increased.

[0036] The amine compound A is present in the epoxy resin curable composition, and the total number of moles of primary amino groups and secondary amino groups, M, is determined based on the number of moles of epoxy groups derived from the epoxy resin, Me, present in the epoxy resin curable composition. 1+2 Molar ratio M 1+2 The amount of each compound can be determined so that the molar ratio M / Me is 0.11 to 0.5. 1+2 The molar ratio M / Me is preferably 0.15 to 0.5, more preferably 0.2 to 0.5, and even more preferably 0.27 to 0.50. 1+2 By setting the molar ratio M / Me to 0.11 or more, the color tone of the cured product becomes excellent, which is preferable. 1+2 By setting / Me to 0.5 or less, the Shore D hardness of the cured product becomes high, which is preferable.

[0037] The amount of amine compound B can be determined so that the molar ratio M3 / Me (the number of moles of tertiary amino groups M3 to the number of moles of epoxy groups derived from the epoxy resin Me present in the epoxy resin curable composition) is 0.005 to 0.1. The molar ratio M3 / Me is preferably 0.01 to 0.095, more preferably 0.015 to 0.09, even more preferably 0.015 to 0.085, and even more preferably 0.02 to 0.08. By setting the molar ratio M3 / Me to 0.005 or more, the Shore D hardness of the cured product is increased, which is preferable. Furthermore, by setting the molar ratio M3 / Me to 0.1 or less, the color tone of the cured product is excellent, which is preferable.

[0038] The amine compound A and the amine compound B are each independently selected from the group consisting of a primary amino group, a secondary amino group, a hydroxyl ... 1+2 The molar ratio M3 / M 1+2 The molar ratio M3 / M is preferably 0.04 to 1.1. 1+2 is more preferably 0.04 to 1.0, even more preferably 0.04 to 0.7, and even more preferably 0.04 to 0.4. 1+2 By making the molar ratio M3 / M3 equal to or greater than 0.04, the Shore D hardness of the cured product becomes high, which is preferable. 1+2 By making the value 1.1 or less, the color tone of the cured product becomes excellent, which is preferable.

[0039] The blending amounts of the amine compound A and the amine compound B can be appropriately designed depending on the physical properties of the cured product. 1+2 / Me and M3 / Me, and preferably the molar ratio M3 / M 1+2The following relationship is satisfied. For example, it is preferable to blend 1 to 30 parts by mass of amine compound A with 100 parts by mass of epoxy resin having two or more epoxy groups per molecule. When the amount of amine compound A is 1 to 30 parts by mass with respect to 100 parts by mass of epoxy resin, a cured product can be obtained that cures quickly, has sufficient adhesive strength, and is excellent in color toning ability. The blend amount of amine compound A with respect to 100 parts by mass of epoxy resin is more preferably 2 to 30 parts by mass, and even more preferably 5 to 30 parts by mass.

[0040] For example, it is preferable to blend 0.5 to 10 parts by mass of amine compound B per 100 parts by mass of epoxy resin having two or more epoxy groups per molecule. When the amount of amine compound B is 0.5 to 10 parts by mass per 100 parts by mass of epoxy resin, a cured product with high Shore D hardness and excellent color tone can be obtained. The blend amount of amine compound B per 100 parts by mass of epoxy resin is more preferably 1 to 9 parts by mass, and even more preferably 1 to 7 parts by mass.

[0041] The epoxy resin curable composition of the present invention cures at room temperature. The epoxy resin curable composition has an excellent color tone after curing, being colorless and / or nearly white. In the present invention, the color tone is excellent when the L of a cured product having a thickness of 8 mm is measured. * a * b * Chromaticity a in the color system * is -10 to +10, and b * is -20 to +20. * If the value is outside the range of −10 to +10, the color tone becomes dark. * a * b * Chromaticity a in the color system * is −9 to +9, and b * The curable epoxy resin composition preferably has an L of 8 mm after curing under conditions of 23°C and 50% RH for 24 hours. * a * b * Chromaticity a in the color system * is −8 to +8, and b *The color of the cured product is -15 to +19. * is more preferably −8 to +5, and even more preferably −7 to +1. * is more preferably −10 to +19, even more preferably −7 to +19, and particularly preferably −5 to +19.

[0042] The epoxy resin curable composition has a cured product with a thickness of 8 mm and a color tone of L. * a * b * In the color space of the color system, lightness L * is preferably 50 or more, more preferably 55 or more, and even more preferably 60 or more.

[0043] Said L * a * b * The color space of a color specification system is a method of displaying colors, which was established by the International Commission on Illumination (CIE) in 1976. It physically measures the amount of color light stimulation that causes color sensation, and expresses lightness (L * value), the degree of magenta and green (a * value), yellow and blue levels (b * The L * A value of 0 represents black, a value of 100 represents white, and * If the value is negative, it represents a greenish color, and if it is positive, it represents a reddish color. * Negative values ​​represent bluer colors, positive values ​​represent yellower colors.

[0044] Said L * a * b * The color space can be determined by measuring using a colorimeter (for example, a colorimeter manufactured by Minolta under the trade name "CR-300"), which is a measuring device specified in Japanese Industrial Standards JIS Z 8781-4:2013.

[0045] The curing time of the epoxy resin curable composition is preferably 1 to 20 minutes. The curing time of the epoxy resin curable composition is more preferably 1 to 15 minutes, and even more preferably 1 to 10 minutes, when 10 g of the epoxy resin curable composition is used and cured at 23°C and 50% RH. A curing time of 1 to 15 minutes is suitable for applications requiring fast curing and is therefore preferred.

[0046] The curing time was measured with reference to the method for determining the pot life of a multi-component adhesive (Method 1) described in JIS K 6870. A thiol compound and an amine compound were mixed in a predetermined ratio with 10 g of epoxy resin under conditions of 23°C and 50% RH, and the curing time was defined as the point at which a toothpick inserted into the epoxy resin curable composition no longer moved.

[0047] When the epoxy resin curable composition is applied to a thickness of 6.0 mm or more and cured at 23°C and 50% RH, the Shore D hardness according to JIS K7215 after 3 hours of curing is preferably 75 or more, and the Shore D hardness according to JIS K7215 after 24 hours of curing is preferably 75 or more. A Shore D hardness of 75 or more after 3 hours of curing is preferred, as it results in a cured product with strong adhesive strength. The Shore D hardness after 3 hours of curing is more preferably 76 to 88, and even more preferably 77 to 85. Furthermore, a Shore D hardness of 75 or more after 24 hours of curing is preferred, as it results in a cured product with strong adhesive strength. The Shore D hardness after 24 hours of curing is more preferably 76 to 83, and even more preferably 78 to 84.

[0048] The epoxy resin curable composition may further contain a filler, a plasticizer, a flexibility-imparting agent, a coupling agent, an antioxidant, a thixotropy-imparting agent, a dispersant, etc., within the scope of not impairing the object of the present invention.

[0049] The epoxy resin curable composition of the present invention can be used as an adhesive that adheres well to metals, glass, stone, concrete, etc. and has excellent color tone. Adhesives containing this epoxy resin curable composition are suitable as adhesives for iron plates, glass, decorative items, watch parts, and everyday carpentry, for example, and are particularly suitable as adhesives for glass, decorative items, watch parts, and everyday carpentry.

[0050] Examples and comparative examples are shown below. In the following examples, unless otherwise specified, common reagents purchased from reagent manufacturers were used as raw materials. The following equipment and methods were used for analysis.

[0051] Curing Time: The curing time of the epoxy resin curable composition was defined as the point at which a toothpick inserted into the epoxy resin curable composition no longer moves, based on the method for determining the pot life of multi-component adhesives (Method 1) described in JIS K 6870. Specifically, a toothpick was inserted into the epoxy resin curable composition obtained by mixing the raw materials according to each example at 23°C and 50% RH, and the curing time was measured at the point at which the toothpick no longer moves. The curing time was measured from the start of mixing and determined in minutes by checking the condition of the toothpick every 30 seconds. In Examples 1 to 7 and Comparative Examples 1 to 11, a thiol compound, amine compound A, and amine compound B were mixed with 10 g of epoxy resin in the proportions shown in Tables 1 and 2.

[0052] Hardness (Shore D Hardness) The hardness of the epoxy resin curable composition was measured according to the method specified in JIS K 7215. Specifically, the epoxy resin curable composition was poured into multiple containers with an inner diameter of 31 mm and a depth of 8 mm in a room at a temperature of 23°C and a humidity of 50% RH. 3 hours and 24 hours after the start of mixing the epoxy resin curable composition, measurement samples with a diameter of 31 mm x 8 mm were obtained. The flat surfaces of the samples were measured using a Type D durometer. The measurement was performed three times for each measurement sample, and the average value was used as the hardness value.

[0053] Lightness and chromaticity The lightness and chromaticity of the cured epoxy resin were measured. Specifically, using a color difference meter (Minolta "CR-300") specified in JIS Z 8781-4, the curable epoxy resin composition according to each example was placed in a container with an inner diameter of 31 mm and a depth of 8 mm and cured at 23°C and 50% RH. After 24 hours, the cured epoxy resin was removed from the container, and the lightness L of the 8 mm-thick cured epoxy resin was measured. * , chromaticity a * , chromaticity b * was measured at room temperature. * and b * The measurement results are shown in Tables 1 and 2.

[0054] Example 1 Under conditions of 23°C and 50% RH, 10 g (100 parts by mass) of "jER828" (bisphenol A-type epoxy resin, epoxy equivalent weight: 184 to 194 g / eq) manufactured by Mitsubishi Chemical Corporation as an epoxy resin having two or more epoxy groups per molecule, 8.8 g (88 parts by mass) of "Polythiol QE-340M" manufactured by Toray Fine Chemicals Co., Ltd. as a thiol compound having two or more thiol groups per molecule, 0.8 g (8 parts by mass) of "BB-AMINE 3138" manufactured by BB Resins SRL as an amine compound A having a primary amine and / or secondary amine, and 0.4 g (4 parts by mass) of "EHC-30" manufactured by ADEKA Corporation as an amine compound B having a tertiary amine were mixed with a spatula for 15 seconds to obtain a curable epoxy resin composition. The number of moles of epoxy groups Me, the number of moles of thiol groups Mt, and the total number of moles of primary amines and secondary amines M of the amine compound A contained in the epoxy resin curable composition are 1+2 , and the number of moles of tertiary amine M3 are listed in Table 1. 1+2 / Me, M3 / Me, M3 / M 1+2 , and Mt / Me were calculated and listed.

[0055] The curing time of the obtained epoxy resin curable composition at 23°C was measured, and it cured in 6 minutes. The Shore D hardness was 78 after 3 hours from the start of curing, and 80 after 24 hours from the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * is -6, b* The result was 18. These results are shown in Table 1.

[0056] Example 2 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amounts of the thiol compound, amine compound A, and amine compound B were changed to 8.6 g (86 parts by mass), 1.1 g (11 parts by mass), and 0.3 g (3 parts by mass).

[0057] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 5 minutes. The Shore D hardness was 78 3 hours after the start of curing, and 80 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -6, b * The result was 19. These results are shown in Table 1.

[0058] Example 3 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amounts of the thiol compound, amine compound A, and amine compound B were changed to 8.7 g (87 parts by mass), 1.1 g (11 parts by mass), and 0.2 g (2 parts by mass).

[0059] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 5 minutes. The Shore D hardness was 79 3 hours after the start of curing, and 79 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * is -6, b * The result was 17. These results are shown in Table 1.

[0060] Example 4 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amounts of the thiol compound, amine compound A, and amine compound B were changed to 8.9 g (89 parts by mass), 0.9 g (9 parts by mass), and 0.2 g (2 parts by mass).

[0061] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 6 minutes. The Shore D hardness was 77 3 hours after the start of curing, and 80 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -6, b *The result was 16. These results are shown in Table 1.

[0062] Example 5 A curable epoxy resin composition was obtained in the same manner as in Example 1, except that the amount of thiol compound was changed to 8.9 g (89 parts by mass) and the amount of amine compound B was changed to 0.3 g (3 parts by mass).

[0063] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 6 minutes. The Shore D hardness was 78 3 hours after the start of curing, and 80 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -6, b * The result was 18. These results are shown in Table 1.

[0064] Example 6 A curable epoxy resin composition was obtained in the same manner as in Example 1, except that the amount of amine compound A was changed to 1.5 g (15 parts by mass) and the amount of amine compound B was changed to 0.1 g (1 part by mass).

[0065] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 4 minutes. The Shore D hardness was 78 3 hours after the start of curing, and 76 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -5, b * The result was 14. These results are shown in Table 1.

[0066] Example 7 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amounts of the thiol compound, amine compound A, and amine compound B were changed to 4.4 g (44 parts by mass), 1.5 g (15 parts by mass), and 0.1 g (1 part by mass).

[0067] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 5 minutes. The Shore D hardness was 84 3 hours after the start of curing, and 83 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * is -6, b * The result was 17. These results are shown in Table 1.

[0068] Comparative Example 1 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.9 g (89 parts by mass), the amine compound A was changed to 1.1 g (11 parts by mass), and the amine compound B was not blended.

[0069] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 6 minutes. The Shore D hardness was 72 3 hours after the start of curing, and 73 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -5, b * The result was 7. The results are shown in Table 1.

[0070] Comparative Example 2 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.9 g (89 parts by mass), the amine compound B was changed to 1.1 g (11 parts by mass), and the amine compound A was not blended.

[0071] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 5 minutes. The Shore D hardness was 82 3 hours after the start of curing, and 83 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * is -8, b * The result was 37. These results are shown in Table 1.

[0072] Comparative Example 3 A curable epoxy resin composition was obtained in the same manner as in Example 1, except that the amount of amine compound A was changed to 1.5 g (15 parts by mass) and the amount of amine compound B was changed to 0.6 g (6 parts by mass).

[0073] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 4 minutes. The Shore D hardness was 80 3 hours after the start of curing, and 78 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -5, b * The result was 22. These results are shown in Table 2.

[0074] Comparative Example 4 A curable epoxy resin composition was obtained in the same manner as in Example 1, except that the amount of amine compound A was changed to 0.3 g (3 parts by mass) and the amount of amine compound B was changed to 0.6 g (6 parts by mass).

[0075] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 7 minutes. The Shore D hardness was 82 3 hours after the start of curing, and 81 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -8, b * The result was 23. These results are shown in Table 2.

[0076] Comparative Example 5 A curable epoxy resin composition was obtained in the same manner as in Example 1, except that the amount of amine compound A was changed to 0.3 g (3 parts by mass) and the amount of amine compound B was changed to 0.1 g (1 part by mass).

[0077] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 15 minutes. The Shore D hardness was 46 3 hours after the start of curing, and 63 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -6, b * The result was 12. These results are shown in Table 2.

[0078] Comparative Example 6 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amount of thiol compound was changed to 13.2 g (132 parts by mass), the amount of amine compound A was changed to 1.5 g (15 parts by mass), and the amount of amine compound B was changed to 0.6 g (6 parts by mass).

[0079] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 5 minutes. The Shore D hardness was 29 3 hours after the start of curing, and 32 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -3, b * The result was 15. These results are shown in Table 2.

[0080] Comparative Example 7 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amounts of the thiol compound, amine compound A, and amine compound B were changed to 4.4 g (44 parts by mass), 1.5 g (15 parts by mass), and 0.6 g (6 parts by mass).

[0081] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 5 minutes. The Shore D hardness was 84 3 hours after the start of curing, and 85 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -7, b * The result was 25. These results are shown in Table 2.

[0082] Comparative Example 8 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound, amine compound A, and amine compound B were changed to 13.2 g (132 parts by mass), 0.3 g (3 parts by mass), and 0.6 g (6 parts by mass).

[0083] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 9 minutes. The Shore D hardness was 38 3 hours after the start of curing, and 39 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * is -6, b * The result was 16. These results are shown in Table 2.

[0084] Comparative Example 9 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amount of thiol compound was changed to 4.4 g (44 parts by mass), the amount of amine compound A was changed to 0.3 g (3 parts by mass), and the amount of amine compound B was changed to 0.6 g (6 parts by mass).

[0085] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 6 minutes. The Shore D hardness was 83 3 hours after the start of curing, and 84 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * -9, b * The result was 26. These results are shown in Table 2.

[0086] Comparative Example 10 A curable epoxy resin composition was obtained in the same manner as in Example 1, except that the amounts of the thiol compound, amine compound A, and amine compound B were changed to 13.2 g (132 parts by mass), 0.3 g (3.0 parts by mass), and 0.1 g (1 part by mass).

[0087] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 17 minutes. The Shore D hardness was 41 3 hours after the start of curing, and 44 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * is -5, b * The result was 10. The results are shown in Table 2.

[0088] Comparative Example 11 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the amount of thiol compound was changed to 4.4 g (44 parts by mass), the amount of amine compound A was changed to 0.3 g (3 parts by mass), and the amount of amine compound B was changed to 0.1 g (1 part by mass).

[0089] The curing time at 23°C was measured in the same manner as in Example 1, and the composition cured in 12 minutes. The Shore D hardness was 10 3 hours after the start of curing, and 27 24 hours after the start of curing. Furthermore, the chromaticity of the cured product of the epoxy resin curable composition was measured. * is -6, b * The result was 12. These results are shown in Table 2.

[0090]

[0091]

Claims

1. An epoxy resin curable composition comprising an epoxy resin having two or more epoxy groups in one molecule, a thiol compound having two or more thiol groups in one molecule, an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group, wherein the number of moles of the epoxy groups contained in the epoxy resin curable composition is Me, the total number of moles of the primary amino group and the secondary amino group is M, １＋２ , the number of moles of tertiary amino groups is M ３ When the molar ratio M １＋２ / Me is 0.11 to 0.5, and the molar ratio M ３ The epoxy resin curable composition according to claim 1, wherein / Me is 0.005 to 0.

1.

2. The total number of moles of the primary amino group and the secondary amino group, M １＋２ The number of moles M of the tertiary amino group relative to ３ Molar ratio M ３ / M １＋２ 2. The epoxy resin curable composition according to claim 1, wherein

3. 3. The epoxy resin curable composition according to claim 1, wherein the molar ratio Mt / Me of the number of moles of the epoxy groups to the number of moles of the thiol groups contained in the epoxy resin curable composition is 0.1 to 0.

9.

4. The epoxy resin curable composition according to claim 1 or 2, wherein the thiol compound has no carbonyl group.

5. L of the cured product ＊ a ＊ b ＊ The chromaticity in the color system is a ＊ is -10 to +10, b ＊ The epoxy resin curable composition according to claim 1 or 2, wherein is −20 to +20.

6. 3. The epoxy resin curable composition according to claim 1, wherein the curing time when 10 g of the epoxy resin curable composition is cured at 23° C. and 50% RH is 1 to 15 minutes.

7. 3. The epoxy resin curable composition according to claim 1 or 2, wherein when the epoxy resin curable composition is applied to a thickness of 6.0 mm or more and cured at 23° C. and 50% RH, the Shore D hardness according to JIS K7215 is 75 or more 3 hours after the start of curing and the Shore D hardness according to JIS K7215 is 75 or more 24 hours after the start of curing.

8. The epoxy resin curable composition according to claim 1 or 2, which is used as an adhesive.

9. An adhesive comprising the epoxy resin curable composition according to claim 1 or 2.