0001 The present invention relates to a compound useful as a crosslinking agent for reactive molecules or reactive high polymer molecules, or an additive, and particularly the present invention relates to an isocyanurate compound having three 1,3-oxathiolane-2-thione rings in a molecule, which is suitably usable as an optical material having a high refractive index such as a plastic lens, an optical fiber or a functional film, and a starting material for a vulcanizing agent of rubber, an ink, a building sealing agent, a sealer or an adhesive agent, and also relates to a method for producing the same, and the present invention further relates to a trithiol isocyanurate compound obtained from the isocyanurate compound and a method for producing the same. 0002 An organic high molecular material is light and easily processible, and therefore has been recently widely used as an optical material such as a plastic lens, an optical fiber or a functional film. However, as compared with an inorganic high molecular material, it has a low refractive index, which is one of important optical properties, and has a large chromatic aberration expressed by an Abbe number, and therefore it has a disadvantage that its use is limited. 0003 On the other hand, an inorganic high molecular material has satisfactory performances in respect of heat resistance, mechanical property or chemical resistance and has a high refractive index, as compared with an organic high molecular material, but it has disadvantages that it is heavy and is not easily processible. 0004 In the production of a conventional organic material having a high refractive index, it has been widely studied to introduce an aromatic ring, a halogen and sulfur in order to obtain a high refractive index. However, in case of introducing an aromatic ring into a structure, it is known that a double refraction is easily caused due to a high orientation property of an aromatic ring and that a transparency is degraded, and since an absorption wavelength of an aromatic ring resides relatively in the vicinity of a visible light part, an Abbe number becomes small and consequently there was a problem of providing a large chromatic aberration. This is caused by maximization of a refractive index in the vicinity of absorption wavelength, which is called as abnormal dispersion, and this is generally well known. Accordingly, it is necessary to produce a molecule containing no aromatic ring, but there have been not so many organic materials having a high refractive index but containing no aromatic ring. 0005 Also, an inorganic high molecular material generally has a refractive index of from 1.46 to 1.92 and an Abbe number of from 25 to 80 in a wide range, but there is not known an organic high refractive index material having a refractive index of around 1.65 and having a large Abbe number of exceeding 40. An organic high refractive index material is desired to be designed so as to provide satisfactory properties by an appropriate combination in respect of an Abbe number and a refractive index, but there is a problem that a material having wide various optical properties is not available at present. Under the circumstances, it is desired to provide an organic high refractive index material having various optical properties in respect of a refractive index and an Abbe number, and it is therefore demanded by a market to provide a novel organic high refractive index material or its starting material. 0006 In order to satisfy the above market's demand, the present invention provides a starting material for an organic high refractive index material having a high Abbe number without degrading a transparency, and a compound useful as a curing agent or a high molecular modifier. Particularly, the present invention provides a novel isocyanurate compound having three 1,3-oxathiolane-2-thione rings in a molecule and its production method as a first invention, and also provides a trithiol isocyanurate compound obtained from the isocyanurate compound and its production method as a second invention. 0007 As the first invention, the first embodiment resides in an isocyanurate compound of the formula (1), 2

0008 wherein R is a hydrogen atom or a methyl group. 0009 The second embodiment resides in tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate according to the first embodiment, wherein R in the formula (1) is a hydrogen atom. 0010 The third embodiment resides in tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate according to the first embodiment, wherein R in the formula (1) is a methyl group. 0011 The fourth embodiment resides in a method for producing an isocyanurate compound of the formula (1), 3

0012 wherein R is a hydrogen atom or a methyl group, which comprises reacting carbon disulfide with a triglycidyl isocyanurate compound of the formula (2), 4

0013 wherein R is a hydrogen atom or a methyl group. 0014 The fifth embodiment resides in the method for producing an isocyanurate compound according to the fourth embodiment, wherein the reaction of carbon disulfide with a triglycidyl isocyanurate compound is carried out in the presence of a catalyst of at least one compound selected from the group consisting of an alkali metal halide, an alkali earth metal halide, an organic base, an alkali metal hydroxide and an onium salt. 0015 The sixth embodiment resides in the method for producing an isocyanurate compound according to the fourth or fifth embodiment, wherein the reaction of carbon disulfide with a triglycidyl isocyanurate compound is carried out by previously mixing carbon disulfide with a catalyst of at least one compound selected from the group consisting of an alkali metal halide, an alkali earth metal halide, an organic base, an alkali metal hydroxide and an onium salt and then adding the triglycidyl isocyanurate compound thereto. 0016 As the second invention, the seventh embodiment resides in a trithlol isocyanurate compound obtained by reacting an isocyanurate compound of the formula (1), 5

0017 wherein R is a hydrogen atom or a methyl group, with a compound having at least one functional group selected from the group consisting of an amino group, an imino group, a hydroxyl group and a thiol group. 0018 The eighth embodiment resides in the trithiol isocyanurate compound according to the seventh embodiment, which is obtained by reacting an isocyanurate compound with a compound having at least one amino group. 0019 The ninth embodiment resides in the trithiol isocyanurate compound according to the seventh or eighth embodiment, which is obtained by reacting an isocyanurate compound with a primary amine having a C1-C6 alkyl group wherein the alkyl group may be substituted optionally with at least one different or same substituent selected from the group consisting of a C1-C4 alkoxy group and a C2-C8 dialkylamino group. 0020 The tenth embodiment resides in the trithiol isocyanurate compound according to the seventh or eighth embodiment, which is obtained by reacting an isocyanurate compound with a benzylamine. 0021 The eleventh embodiment resides in the trithiol isocyanurate compound according to the seventh or eighth embodiment, which is obtained by reacting an isocyanurate compound with a secondary benzylamine having a C1-C6 alkyl group. 0022 The twelfth embodiment resides in the trithiol isocyanurate compound according to the seventh or eighth embodiment, which is obtained by reacting an isocyanurate compound with a primary amine having a C1-C6 alkenyl group. 0023 The thirteenth embodiment resides in a method for producing a trithiol isocyanurate compound, which comprises reacting an isocyanurate compound of the formula (1), 6

0024 wherein R is a hydrogen atom or a methyl group, with a compound having at least one functional group selected from the group consisting of an amino group, an imino group, a hydroxyl group and a thiol group. 0025 The fourteenth embodiment resides in the method for producing a trithiol isocyanurate compound according to the thirteenth embodiment, which comprises reacting an isocyanurate compound with a compound having at least one amino group. 0026 The fifteenth embodiment resides in the method for producing a trithiol isocyanurate compound according to the thirteenth or fourteenth embodiment, which comprises reacting an isocyanurate compound with a primary amine having a C1-C6 alkyl group wherein the alkyl group may be substituted optionally with at least one different or same substituent selected from the group consisting of C1-C4 alkoxy group and a C2-C8 dialkylamino group. 0027 The sixteenth embodiment resides in the method for producing a trithiol isocyanurate compound according to the thirteenth or fourteenth embodiment, which comprises reacting an isocyanurate compound with a benzylamine. 0028 The seventeenth embodiment resides in the method for producing a trithiol isocyanurate compound according to the thirteenth or fourteenth embodiment, which comprises reacting an isocyanurate compound with a secondary benzylamine having a C1-C6 alkyl group. 0029 The eighteenth embodiment resides in the method for producing a trithiol isocyanurate compound according to the thirteenth or fourteenth embodiment, which comprises reacting an isocyanurate compound with a primary amine having a C1-C6 alkenyl group. 0030 An isocyanurate compound having three 1,3-oxathiolane-2-thione rings of the first invention is expressed by the following formula (1), 7

0031 (wherein R is a hydrogen atom or a methyl group). 0032 In the formula (1), when R is a hydrogen atom, the formula (1) expresses tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate, and when R is a methyl group, the formula (1) expresses tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. 0033 The production method of the first invention is fully explained in details hereinafter. 0034 The above isocyanurate compound of the first invention is produced by reacting at least 3 mol, preferably from 3 to 10 mol, more preferably from 3 to 5 mol of carbon disulfide with one mol of a triglycidyl isocyanurate compound. The triglycidyl isocyanurate compound used herein is expressed by the following formula (2), 8

0035 (wherein R is a hydrogen atom or a methyl group). 0036 In the above formula (2), when R is a hydrogen atom, the formula (2) expresses tris(2,3-epoxypropyl)isocyanurate, and when R is a methyl group, the formula (2) expresses tris(2-methyl-2,3-epoxypropyl)isocyanurate. 0037 When using a triglycidyl isocyanurate, i.e. tris(2,3-epoxypropyl)isocyanurate, as a starting material, the obtained isocyanurate compound is tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 1,3,5-tris(1,3-oxathiolane-2-thion-5-ylmethyl)-1,3,5-triazine-2,4-6-trione. 0038 When using tris(2-methyl-2,3-epoxypropyl)isocyanurate as a starting material having a methyl group for R in the formula (2), the obtained isocyanurate compound is tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate1,3,5-tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)-1,3,5-triazine-2,4-6-trione. 0039 A triglycidyl isocyanurate compound used as a starting material may be produced by any method, but tris(2,3-epoxypropyl)isocyanurate is commercially easily available as TEPIC (tradename) manufactured by Nissan Chemical Industries, Ltd. Further, by using TEPIC-S (tradename) commercially available as a high purity product and manufactured by Nissan Chemical Industries, Ltd., a side reaction can be inhibited and tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate having a high purity can be obtained at a high yield. 0040 Also, by using TEPIC-H (tradename) commercially available as a high melting point type product, tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate having a high pyrolysis temperature can be preferably obtained. The TEPIC-H used as a starting material is a compound providing a highly crystalline type crystal having a high melting point which comprises a pair of optically active substances of triglycidyl isocyanurate, i.e. (2R,2R,2R)-tris(2,3-epoxypropyl)isocyanurate and (2S,2S,2S)-tris(2,3-epoxypropyl)isocyanurate, and can be produced, for example, as described in EP 0952155 Al (corresponding to Japanese Patent publication: JP 2000007672 A). The tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate derived from the type tris(2,3-epoxypropyl)isocyanurate has a low solubility to various organic solvents as compared with other isomers, and provides an excellent storage stability when made into a one-pack type composition since its reaction-proceeding speed is low during storing. Thus, by using a high melting point type crystal of tris(2,3-epoxypropyl)isocyanurate, i.e. (2R,2R,2R)-tris(2,3-epoxypropyl)isocyanurate and (2S,2S,2S)-tris(2,3-epoxypropyl)isocyanurate, as a starting material, a 1:1 mixture of (1R,1R,1R)-tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and (1S,1S,1S)-tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate, having a high melting point and a low solubility, can be obtained. 0041 Also, by using an optically active tris(2,3-epoxypropyl)isocyanurate described in EP 1061080A1 (corresponding to Japanese Patent Publication: JP 11315078 A) as a starting material, its corresponding optically active tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate can be produced. For example, when using (2R,2R,2R)-tris(2,3-epoxypropyl)isocyanurate as a starting material, (1R,1R,1R)-tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate can be obtained. 0042 Also, with regard to tris(5-methyl-1-3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained by using tris(2-methyl-2,3-epoxypropyl)isocyanurate as a starting material, there is present the same optically active substance as described above. For example, when using (2R,2R,2R)-tris(2-methyl-2,3-epoxypropyl)isocyanurate as a starting material, (1R,1R,2R)-tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate can be obtained. 0043 For carbon disulfide, 1,3-oxathiolane-2-thione or its compound can be used as a compound equivalent to carbon dioxide. In this case, carbon dioxide is generated in the system by equilibrium reaction, and it is considered to provide an aimed product by reacting the carbon disulfide with an isocyanurate compound. 0044 In the first invention, the reaction between a triglycidyl isocyanurate compound and carbon disulfide is carried out efficiently in the presence of a catalyst of at least one compound selected from the group consisting of an alkali metal halide, an alkali earth metal halide, an organic base, an alkali metal hydroxide and an onium salt to produce an isocyanurate compound having three 1,3-oxathiolane-2-thione rings in a molecule. 0045 Hereinafter, examples of a catalyst used in the production of an isocyanurate compound of the first invention are illustrated below. 0046 Examples of the alkali metal halide include a lithium halide such as lithium chloride or lithium bromide, a sodium halide such as sodium chloride, sodium bromide or sodium iodide, a potassium halide such as potassium chloride, potassium bromide or potassium iodide, and the like. Examples of the alkali earth metal halide include a magnesium halide such as magnesium chloride or magnesium bromide, a calcium halide such as calcium chloride or calcium bromide, and the like. Examples of the organic base include any of generally basic organic compounds which do not participate in the reaction, for example, alkylamines such as triethylamine, diethylisopropylamine or dimethylbenzylamine, cyclic amines such as hexamethylenetetramine, pyridine, 4-dimethylaminopyridine, piperidine, piperazine, N-methylpiperidine, N,N-dimethylpiperazine, pyridine or imidazole, and an alkali metal alkoxide such as sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide or potassium t-butoxide. 0047 Examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide or lithium hydroxide. 0048 Examples of the onium salt include an ammonium salt, a phosphonium salt, an arsonium salt, a stibonium salt, an oxonium salt, a sulfonium salt, a selenonium salt, a stannonium salt or a iodonium salt. Also, examples of the onium salt used in the first invention include an ammonium salt, a phosphonium salt, an arsonium salt, a stibonium salt, an oxonium salt, a sulfonium salt, a selenonium salt, a stannonium salt or a iodonium salt. Examples of typical compounds include a quaternary ammonium salt such as trimethylbenzylammonium halide, triethylbenzylammonium halide, trioctylmethylammonium halide, tributylbenzylammonium halide or trimethylbenzylammonium halide. Also, examples of a quaternary phosphonium salt include a tetraalkylphosphonium halide such as tetra n-butylphosphonium halide or terra n-propylphosphonium halide, a trialkylbenzylphosphonium halide such as triethylbenzylphosphonium halide, a triphenylmonoalkylphosphonium halide such as triphenylmethylphosphonium halide or triphenylethylphosphonium halide, a triphenylbenzylphosphonium halide, a tetraphenylphosphonium halide, a tritolylmonoarylphosphonium halide, or a tritolylmonoalkylphosphonium halide. Among the onium salts, a quaternary ammonium salt or a quaternary phosphonium salt is particularly preferable. A quaternary ammonium salt is known to form a highly basic quaternary ammonium base by being treated with wet silver oxide or sodium hydroxide or with an anion exchange resin to substitute a counter ion (such as a halogen ion) with a hydroxyl ion (OH), but these compounds also can be used as a preferable organic base. 0049 The catalyst may be used in a combination of two or more, and is used in a total catalyst amount of from 0.001 to 0.3 mol, preferably from 0.01 to 0.15 mol, to 1 mol of a triglycidyl isocyanurate compound. 0050 A solvent used in the production of an isocyanurate compound of the first invention may be any solvent so long as it is inert, typical examples of which include amides such as N,N-dimethylformamide, N,N-dimethylacetamide or N-methyl-2-pyrrolidone, which is known as an aprotic polar solvent, a sulfur compound such as dimethylsulfoxide, or cyclohexanone. Examples of other solvents include aromatic hydrocarbons such as toluene or chlorobenzene, ethers such as dioxane, dimethoxyethane or tetrahydrofuran, halogenated hydrocarbons such as dichloroethane or chloroform, ketones such as acetone or methyl ethyl ketone, nitrites such as acetonitrile, nitro compounds such as nitroethane or nitrobenzene, esters such as ethyl acetate, or their mixtures. Also, other solvents such as alcohols including methanol, ethanol, isopropanol, 2-methoxyethanol or 2-ethoxyethanol, can be used, provided that they do not participate in the reaction. 0051 The reaction using a solvent in the production of an isocyanurate compound of the first invention is carried out at a reaction temperature of from 78 C. to a boiling point of a solvent used, preferably in a range of from 0 C. to 100 C. 0052 An isocyanurate compound of the first invention can be produced by mixing a triglycidyl isocyanurate compound, carbon disulfide, a catalyst and optionally a solvent in a reactor at the same time, but may be produced by previously placing a triglycidyl isocyanurate compound, a catalyst and optionally a solvent in a reactor and then dropwise adding carbon disulfide thereto. However, a more preferable production method comprises previously mixing carbon disulfide, at least one catalyst compound selected from the group consisting of an alkali metal halide, an alkali earth metal halide, an organic base, an alkali metal hydroxide and an onium salt, and optionally a solvent, and then adding a triglycidyl isocyanurate compound thereto. By producing an isocyanurate compound according to this method, a side reaction hardly occurs and consequently an isocyanurate compound having a high purity can be obtained. 0053 The isocyanurate compound thus obtained in the above production method can be purified by washing, recrystallizing or reprecipitating to remove impurities including a starting material, a catalyst or a by-product. It is preferable to use a solvent for the washing step in the purification process, which has a low solubility to the isocyanurate compound product and has a power of dissolving impurities, and examples of such a preferable solvent include water, alcohols such as methanol or ethanol, ethers such as diethyl ether, tetrahydrofuran or dioxane, and the like. Also, in the purification by reprecipitation, the isocyanurate compound product is once dissolved in a polar solvent such as dimethylsulfoxide, cyclohexanone, N-methyl-2-pyrrolidone or dimethylformamide, and the resultant solution is placed in an alcohol such as methanol to precipitate a crystal which is then filtrated out, thereby removing impurities. The isocyanurate compound product purified in this manner has an improved pyrolysis temperature, and is decolored to some extent when it is colored by the reaction. 0054 The isocyanurate compound obtained in the first invention has a large sulfur content to its molecular weight, and consequently has a high refractive index, and it is accordingly used as an additive for other materials to provide an organic material having a high refractive index. For example, the isocyanurate compound thus obtained can be mixed with a transparent resin such as acrylic resin, polyester resin or polyvinyl chloride to provide a material having a high refractive index. 0055 The isocyanurate compound of the first invention can be preferably used not only by physically mixing with the above-mentioned resins or other monomer compounds but also by chemically reacting with other materials to provide materials excellent in adhesive properties or optical properties. This can be effected by using an active hydrogen-containing reactive compound having a reactivity to a functional group such as a 1,3-oxathiolane-2-thion-5-ylmethyl group or a 5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl group in the isocyanurate compound. Preferable examples of an active hydrogen-containing functional group include an amino group, an imino group, a hydroxyl group, a thiol group and the like. When using a resin as the reactive compound, by using a resin containing at least one functional group selected from the group consisting of an amino group, an imino group, a hydroxyl group and a thiol group, the isocyanurate compound of the first invention works as a crosslinking agent to provide a material excellent in adhesive properties and optical properties. Examples of a resin used in this case include the above-mentioned transparent resins such as acrylic resin, polyester resin or polyvinyl chloride, having an amino group, an imino group, a hydroxyl group or a thiol group introduced therein. 0056 A trithiol isocyanurate compound of the second invention is provided by reacting an active hydrogen-containing reactive compound with a functional group such as a 1,3-oxathiolane-2-thion-5-ylmethyl group or a 5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl group in an isocyanurate compound of the first invention. 0057 The above reaction may be carried out in the presence of a catalyst such as an alkali metal halide, an alkali earth metal halide, an organic base, an alkali metal hydroxide or an onium salt used in the above production of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. Also, in case of reacting with a compound having an amino group or an imino group, by using the compound having an amino group or an imino group in an excess amount, it works as a catalyst to accelerate the reaction. These reactions may be carried out without using a solvent, but it is preferable to carry out by dispersing or dissolving the reactants in an organic solvent. 0058 When reacting the above compound having an amino group or an imino group with tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate, an addition reaction with a part or all of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate is carried out by the above catalytic action to produce a trithiol isocyanurate compound as a thiocarbamate compound. 0059 Examples of a trithiol isocyanurate compound obtained by reacting with a reactive compound having at least one functional group selected from the group consisting of an amino group, an imino group, a hydroxyl group and a thiol group include a compound of the following formula (3), 9

0060 (wherein R1 is a hydrogen atom or a methyl group, and X is an NHR2 group, an NR3R4 group, an OR5 group or an SR6 group, in which R2, R3, R4, R5 and R6 are respectively a hydrogen atom, a C1-C6 alkyl group (which may be substituted optionally with at least one different or same substituent selected from the group consisting of a C1-C4 alkoxy group and a C2-C8 dialkylamino group), a C1-C6 alkenyl group or a benzyl group). 0061 Now, concrete chemical structures of the reaction products are illustrated hereinafter. 0062 A trithiolisocyanurate compound obtained from tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and a compound having an amino group is expressed by the following formula (4). 10

0063 A reaction product obtained from tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and a compound having an imino group is expressed by the following formula (5). 11

0064 A reaction product obtained from tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and a compound having a hydroxyl group is expressed by the following formula (6). 12

0065 A reaction product obtained from tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and a compound having a thiol group is expressed by the following formula (7). 13

0066 In the above formulae (4) to (7), each of R2, R3, R4, R5 and R6 corresponds to that of a compound having at least one functional group selected from the group consisting of an amino group, an imino group, a hydroxyl group and a thiol group to be reacted, and when each of R2, R3, R4, R5 and R6 is a methyl group, each of corresponding starting materials is methylamine in case of a compound having an amino group, dimethylamine in case of a compound having an imino group, methyl alcohol in case of a compound having a hydroxyl group and methylthiol in case of a compound having a thiol group. 0067 A production method of the second invention is fully is described in more details hereinafter. 0068 A tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate compound used as a starting material may be prepared by any method, and can be easily prepared from tris(2,3-epoxypropyl)isocyanurate (easily commercially available as TEPIC (tradename) manufactured by Nissan Chemical Industries, Ltd.) as described below. Also, it is preferable to use tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate having a high purity, which is prepared from TEPIC-S (tradename) commercially available as a high purity product manufactured by Nissan Chemical Industries, Ltd. Further, it is possible to use tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate prepared from TEPIC-H (tradename) commercially available as a high melting point type product. Still further, it is also possible to use optically active tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate as a starting material, which is prepared from optically active tris(2,3-epoxypropyl)isocyanurate, as described in JP-A-11-315078. For example, (2R,2R,2R)-tris(2,3-epoxypropyl)isocyanurate produces tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate having all of three asymmetric carbons composed of steric configuration of R, and a trithiol isocyanurate obtained therefrom also has all of three asymmetric carbons composed of steric configuration of R. 0069 Examples of a compound having at least one functional group selected from the group consisting of an amino group, an imino group, a hydroxyl group and a thiol group, which is used as a reactive compound having an active hydrogen atom in the second invention, are illustrated below. 0070 Examples of a compound having an amino group include a primary amine. Concrete examples of a primary amine having a C1-C6 alkyl group (which may be substituted optionally with at least one different or same substituent selected from the group consisting of a C1-C4 alkoxy group and a C2-C8 dialkylamino group) include aliphatic monoamines such as methylamine, ethylamine, butylamine, pentylamine, hexylamine, aminocyclohexane, methoxyethylamine, ethoxyethylamine, 3-methoxypropylamine, 3-ethoxypropylamine, N,N-dimethylethylenediamine, 3-(diethylamino)propylamine, 3-(dibutylamino)propylamine or the like, and examples of a primary amine having a C1-C6 alkenyl group include unsaturated alkylamines such as allylamine, aromatic monoamines such as aniline, benzylamine or phenethylamine, aliphatic diamines such as ethylenediamine or hexamethylenediamine, aromatic diamines such as phenylenediamine or xylylenediamine, and the like. 0071 Examples of a compound having an imide group include a secondary amine. Concrete examples of the secondary amine include aliphatic monoamines such as dimethylamine, diethylamine, dibutylamine, dihexylamine or dicyclohexylamine, aromatic monoamines such as diphenylamine or dibenzylamine, and concrete examples of a secondary benzylamine having a C1-C6 alkyl group include N-methylbenzylamine, N-ethylbenzylamine, N-butylbenzylamine, N-pentylbenzylamine or N-hexylbenzylamine. Other three or more functional amines or amines substituted with a hetero ring may also be used, and for example, melamine, guanamine, imidazoles or the like may be used. Also, isocyanuric acid included in amines may be used as an active hydrogen-containing reactive compound having a reactivity to a 1,3-oxathiolane-2-thione ring. 0072 Examples of a compound having a hydroxyl group include aliphatic monoalcohols such as methanol, ethanol, hexanol or 2-ethyl-hexanol, aromatic monoalcohols such as phenol or naphthol, glycols such as ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol or neopentyl glycol, and examples of three or more functional compounds include glycerin, trimethylolpropane, pentaerythritol or dipentaerythritol. 0073 Examples of a compound having a thiol group include aliphatic monothiols such as methanethiol, ethanethiol, hexanethiol or 2-ethyl-hexanethiol, aromatic monothiols such as benzenethiol or naphthalenethiol, and dithiols such as ethylenedithiol, propylenedithiol or neopentyldithiol. 0074 Also, it is possible to use a compound having at least two or more of an amino group, an imino group, a hydroxyl group and a thiol group in combination in a molecule, examples of which include amino alcohols such as monoethanolamine or diethanolamine, and polyamines such as diethylene triamine, triethylene tetramine or hexamethylene tetramine. 0075 The second invention is not limited to the above illustrated compounds, and these compounds may have a substituent such as a halogen or a nitro group to such an extent as not to participate in the reaction, and may have a bonding group such as ester, ether or sulfide (S) in a molecule. 0076 Further, when using a compound having at least two functional groups in a molecule as a compound having at least one functional group selected from the group consisting of an amino group, an imino group, a hydroxyl group and a thiol group used in the second invention, a crosslinking reaction is caused to form a gel insoluble in a solvent. The above crosslinking reaction produces a reactive crosslinked gel having a thiol group therein, and the reactive crosslinked gel thus produced has an ability of modifying various functions by reacting with a compound reactive with the thiol group in the crosslinked gel. 0077 In the second invention, the reaction of an isocyanurate compound with an amino group, an imino group, a hydroxyl group or a thiol group to produce a trithiol isocyanurate compound is carried out optionally in the presence of a catalyst such as a Lewis acid, an onium salt, an inorganic base, an organic base, an alkali metal hydride, an alkali metal hydroxide, an alkali metal halide, an alkali earth metal halide, an organic acid or the like. 0078 Examples of a catalyst used in the production of a trithiol isocyanurate compound of the second invention are illustrated below. 0079 Examples of the Lewis acid include aluminum chloride, tinchloride, titanium tetrachloride, boron trifluoride-etherate, triisopropoxy aluminum, ytterbium trifrate, and the like. Examples of the alkali metal halide include a lithium halide such as lithium chloride or lithium bromide, a sodium halide such as sodium chloride, sodium bromide or sodium iodide, a potassium halide such as potassium chloride, potassium bromide or potassium iodide, and the like. 0080 Examples of the alkali earth metal halide include a magnesium halide such as magnesium chloride or magnesium bromide, a calcium halide such as calcium chloride or calcium bromide, and the like. The organic base may be any organic compound generally having a basic property and not participating in the reaction, examples of which include alkylamines such as triethylamine, diethylisopropylamine or dimethylbenzylamine, cyclic amines such as hexamethylenetetramine, pyridine, 4-dimethylaminopyridine, piperidine, piperazine, N-methylpiperidine, N,N-dimethylpiperazine, pyridine or imidazole, and alkali metal alkoxides such as sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide or potassium t-butoxide, and the like. 0081 Examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide or lithium hydroxide. 0082 Examples of the alkali metal hydride include sodium hydride or potassium hydride. 0083 Examples of the inorganic base include potassium carbonate, cesium carbonate or potassium hydrogencarbonate. 0084 Examples of the onium salt include an ammonium salt, a phosphonium salt, an arsonium salt, a stibonium salt, an oxonium salt, a sulfonium salt, a selenonium salt, a stannonium salt and a iodonium salt. Examples of the onium salt used in the present invention include an ammonium salt, a phosphonium salt, an arsonium salt, a stibonium salt, an oxonium salt, a sulfonlum salt, a selenonium salt, a stannonium salt and a iodonium salt. Typical examples of these compounds include a quaternary ammonium salt such as trimethylbenzylammonium halide, triethylbenzylammonium halide, trioctylmethylammonium halide, tributylbenzylammonium halide or trimethylbenzylammonium halide. Also, example of a quaternary phosphonium salt include a tetraalkylphosphonium halide such as tetra n-butylphosphonium halide or tetra n-propylphosphonium halide, a trialkylbenzylphosphonium halide such as triethylbenzylphosphonium halide, a triphenylmonoalkylphosphonium halide such as triphenylmethylphosphonium halide or triphenylethylphosphonium halide, a triphenylbenzylphosphonium halide, a tetraphenylphosphonium halide, a tritolylmonoarylphosphonium halide, or a tritolylmonoalkylphosphonium halide. Among these onium salts, a quaternary ammonium salt or a quaternary phosphonium salt is particularly preferable. The quaternary ammonium salt is known to provide a strongly basic quaternary ammonium base by being treated with wet silver oxide or sodium hydroxide or an anion exchange resin to have a halogen ion as a counter ion substituted with a hydroxyl ion (OH), and this can be used also as a preferable organic base. 0085 The catalyst may be used in a combination of two or more, and is used in a total catalyst amount of from 0.001 to 0.3 mol, preferably from 0.01 to 0.15 mol, to 1 mol of an isocyanurate compound obtained in the first invention. 0086 Also, when reacting with a compound having an amino group or an imino group, the compound having an amino group or an imino group is used preferably in an excess amount to accelerate the reaction. It is preferable to use the compound having an amino group or an imino group in an amount of at least 3 mol, preferably from 3 to 20 mol, more preferably from 3 to 10 mol, to 1 mol of an isocyanurate compound. 0087 A solvent used in the production of a trithiol isocyanurate compound of the second invention may be any solvent so long as it is inert, typical examples of which include amides such as N,N-dimethylformamide, N,N-dimethylacetamide or N-methyl-2-pyrrolidone, which is known as an aprotic polar solvent, a sulfur compound such as dimethylsulfoxide, or cyclohexanone. Other examples of the solvent include aromatic hydrocarbons such as toluene or chlorobenzene, ethers such as dioxane, dimethoxyethane or tetrahydrofuran, halogenated hydrocarbons such as dichloroethane or chloroform, ketones such as acetone or methyl ethyl ketone, nitrites such as acetonitrile, nitro compounds such as nitroethane or nitrobenzene, esters such as ethyl acetate, or their mixtures. Also, a solvent such as alcohols including methanol, ethanol, isopropanol, 2-methoxyethanol or 2-ethoxyethanol may be used, provided that they do not participate in the reaction. 0088 In the production of a trithiol isocyanurate compound of the second invention, an unpreferable coloration is sometimes caused when using ketones such as cyclohexanone, acetone or methyl ethyl ketone as a solvent among the above solvents for mixing with a compound having particularly an amino group in a molecule. 0089 In the second invention, the reaction is carried out at a reaction temperature of from 78 C. to a boiling point of a solvent used, preferably in a range of from 0 C. to 100 C. 0090 Further, since an oxidation reaction from the obtained thiol into disulfide also proceeds, it is preferable to carry out the reaction in an inert gas such as nitrogen or argon. A solvent may not be used for carrying out these reactions, but it is preferable to carry out the reaction by dispersing or dissolving in an organic solvent. 0091 A trithiol isocyanurate compound of the second invention such as reaction products illustrated by the above formulae (4) to (7) easily forms a cured product having a disulfide (SS) bond by oxidation polymerization due to oxygen in an oxygen atmosphere or air. 0092 This reaction is explained below by the following chemical structural formulae. Methylamine is addition-reacted to tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate to form a trithiol isocyanurate compound having the following structural formula (8), 14

0093 and the product thus formed is oxidized in air to form a cured product bonded by such a disulfide structure unit as illustrated by the following formula (9). 15

0094 An isocyanurate compound forms a thiol in the compounds as illustrated by the above formulae (3) to (8) by reacting with the above-mentioned active hydrogen-containing reactive compound. 0095 A solvent used in the production of a trithiol isocyanurate compound of the second invention may be any solvent, provided that it is inert, typical examples of which include amides such as N,N-dimethylformamide, N,N-dimethylacetamide or N-methyl-2-pyrrolidone, known as an aprotic polar solvent, sulfur compounds such as dimethylsulfoxide, or cyclohexanone. Examples of other solvents include aromatic hydrocarbons such as toluene or chlorobenzene, ethers such as dioxane, dimethoxyethane or tetrahydrofuran, halogenated hydrocarbons such as dichloroethane or chloroform, ketones such as acetone or methyl ethyl ketone, nitriles such as acetonitrile, nitro compounds such as nitroethane or nitrobenzene, esters such as ethyl acetate, or their mixtures. Also, a solvent such as alcohols including methanol, ethanol, isopropanol, 2-methoxyethanol or 2-ethoxyethanol, may be used, provided that it does not participate in the reaction. 0096 In the production of a trithiol isocyanurate compound of the second invention, an unpreferable coloration is sometimes caused when using ketones such as cyclohexanone, acetone or methyl ethyl ketone among the above solvents for mixing with a compound having particularly an amino group in a molecule. 0097 When using a solvent, the reaction of the second invention is carried out at a reaction temperature of from 78 C. to a boiling of the solvent, preferably in a range of from 0 C. to 100 C. 0098 Also, a trithiol isocyanurate compound obtained in the second invention forms a cured product by a crosslinking reaction by mixing with a compound having at least two functional groups in a molecule, which are reactive with a thiol group in the compound. Examples of this functional group include isocyanate (NCO), thioisocyanate (NCS), acid anhydride, acid chloride, alkyl halide and epoxy groups. Concrete examples include isocyanates such as hexamethylene diisocyanate, toluyl diisocyanate, isophorone diisocyanate or diphenylmethane diisocyanate, acid chlorides such as terephthalic acid dichloride, alkyl halides such as xylene dichloride or xylene dibromide, glycidyl compounds such as bisphenol A diglycidyl ether, terephthalic acid diglycidyl ester or N,N-diglycidylaniline, and the like. 0099 The crosslinking reaction of a trithiol isocyanurate compound is carried out optionally in the presence of a catalyst such as an onium salt, an inorganic base or an organic base. 0100 Their concrete examples are illustrated below. The organic base may be any compound such as generally basic organic compounds, provided that it does not participate in the reaction, examples of which include alkylamines such as triethylamine, diethylisopropylamine or dimethylbenzylamine, cyclic amines such as hexamethylenetetramine, pyridine, 4-dimethylaminopyridine, piperidine, piperazine, N-methylpiperidine, N,N-dimethylpiperazine, pyridine or imidazole, alkali metal alkoxides such as sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide or potassium t-butoxide, and the like. 0101 Examples of the inorganic base include potassium carbonate, cesium carbonate, potassium hydrogencarbonate, and the like. 0102 Examples of the onium salt include an ammonium salt, a phosphonium salt, an arsonium salt, a stibonium salt, an oxonium salt, a sulfonium salt, a selenonium salt, a stannonium salt, an iodonium salt, and the like. Also, examples of the onium salt used in the present invention include an ammonium salt, a phosphonium salt, an arsonium salt, a stibonium salt, an oxonium salt, a sulfonium salt, a selenonium salt, a stannonium salt, a iodonium salt, and the like. Typical examples of a quaternary ammonium salt include trimethylbenzylammonium halide, triethylbenzylammonium halide, trioctylmethylammonium halide, tributylbenzylammonium halide, trimethylbenzylammonium halide, and the like. Also, examples of a quaternary phosphonium salt include a tetraalkylphosphonium halide such as tetra n-butylphosphonium halide or tetra n-propylphosphonium halide, a trialkylbenzylphosphonium halide such as triethylbenzylphosphonium halide, a triphenylmonoalkylphosphonium halide such as triphenylmethylphosphonium halide or triphenylethylphosphonium halide, a triphenylbenzylphosphonium halide, a tetraphenylphosphonium halide, a tritolylmonoarylphosphonium halide, or a tritolylmonoalkylphosphonium halide. Among the onium salts, a quaternary ammonium salt and a quaternary phosphonium salt are particularly preferable. The quaternary ammonium salt is known to form a strongly basic quaternary ammonium base by being treated with wet silver oxide or sodium hydroxide, or an anion exchange resin to substitute a halogen ion as a counter ion with a hydroxyl ion (OH), and these can be used also as a preferable organic base. 0103 The catalyst may be used in a combination of two or more, and is used in a total catalyst amount of from 0.001 to 0.3 mol, preferably from 0.01 to 0.15 mol, to 1 mol of an isocyanurate compound obtained in the first invention. 0104 The crosslinking reaction of a trithiol isocyanurate compound is carried out preferably in the absence of a solvent, but it may be carried out in the presence of a solvent, if necessary. Examples of the solvent to be used may be any solvent, provided that it is inert to the reaction, typical examples of which include amides such as N,N-dimethylformamide, N,N-dimethylacetamide or N-methyl-2-pyrrolidone, known as an aprotic polar solvent, sulfur compounds such as dimethylsulfoxide, aromatic hydrocarbons such as toluene or chlorobenzene, ethers such as dioxane, dimethoxyethane or tetrahydrofuran, halogenated hydrocarbons such as dichloroethane or chloroform, ketones such as acetone, methyl ethyl ketone or cyclohexanone, nitrites such as acetonitrile, nitro compounds such as nitroethane or nitrobenzene, esters such as ethyl acetate, or their mixtures. Also, solvents such as alcohols including methanol, ethanol, isopropanol, 2-methoxyethanol or 2-ethoxyethanol, and amines including triethylamine or pyridine, may be used, provided that they do not participate in the reaction. 0105 As mentioned above, an isocyanurate compound of the first invention or a trithiol isocyanurate compound of the second invention is characterized by providing a material having a high refractive index due to a high sulfur content to a molecular weight of the compound itself when it is used as a composition or as a curing agent or an additive. Further, the isocyanurate compound alone can be polymerized in the presence of a basic material as a catalyst. 0106 Further, the isocyanurate compound of the first invention or the trithiol isocyanurate compound of the second invention does not have a benzene ring in its structure, and consequently less absorbs ultraviolet light in a long wavelength zone so that it can be used as a starting material for providing an excellent optical material having a relatively large Abbe number and a small chromatic aberration. Further, when it is used as a curing agent, it provides a tri-dimensional crosslinked structure excellent in isotropy, and consequently its double refraction is small, thus providing an excellent transparency. 0107 Still further, tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate is characterized by having a relatively low solubility to a solvent, and consequently it is possible to provide a one-pack type reactive mixture liquid together with a high molecular compound having a reactive substituent, which can be stored for a long time. Particularly, tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained from TEPIC-H (tradename: type tris(2,3-epoxypropyl)-isocyanurate) manufactured by Nissan Chemical Industries, Ltd. is characterized by its low solubility to a solvent as compared with other isomers.

EXAMPLES 0108 Hereinafter, the present invention is further illustrated with reference to Examples, but should not be limited thereto. Also, analysis processes employed in the Examples are explained below. 0109 Mass Spectrometric Analysis Method (MASS)0110 A method employed in the Examples was an FD method (field desorption method). An FD method apparatus employed was SX-102 manufactured by JEOL Ltd. 0111 Proton Nuclear Magnetic Resonance Method (1H-NMR)0112 An identification method of reaction products in the Examples employed INOVA400 manufactured by Varian, Inc. as a 1H-NMR apparatus, deuterated dimethylsulfoxide or deuterated chloroform as a measuring solvent, and tetramethylsilane as a standard material. 0113 Melting Point Measurement, Thermal Analysis Conditions0114 A melting point measuring method in each of the Examples employed TG/DTA320U manufactured by Seiko Instruments Inc., as a thermal analysis apparatus, and an endothermic temperature was defined as a melting point. 0115 Tg Measuring Conditions0116 A Tg measuring method in each of the Examples employed DSC8230 manufactured by Rigaku International Corp., as a thermal analysis apparatus. 0117 Purity Measuring Conditions0118 Each Example was employed a liquid chromatography (HPLC) as a purity measuring condition. An apparatus employed was a liquid chromatography apparatus manufactured by JASCO Corporation and detection was carried out at UV280 nm by using a UV detector (model No. UV-1575) as a detector. A column employed was ODS-3 (4.6 mm250 mm) manufactured by GL Sciences Inc., and the purity measurement was carried out by using an oven temperature of 40 C., acetonitrile/water1.5:1 as an eluate, and 4-t-butyl-toluene as an internal standard material. 0119 Molecular Weight Measuring Conditions0120 A gel permeation chromatography (GPC) was employed for the molecular weight measuring conditions in each Example. An apparatus employed was SSC-7200 manufactured by Senshu Scientific Co., Ltd. and calculation was carried out in terms of polystyrene conversion. The measurement was carried out by using DMF as an eluate. 0121 Refractive Index, Abbe Number Measurement0122 A refractive index measurement method in Examples 9 to 10 employed DUV-VASE manufactured by J. A. Woollam Japan Corp. as a multi-incident spectroellipsometry, and a refractive index (ND) was measured by 589 nm, and an Abbe number (D) was calculated in accordance with the following calculation formula.

D(nD1)/(nFnC)

0123 In the above calculation formula, nC represents a refraction index at 656 nm, nD represents a refraction index at 589 nm and nF represents a refraction index at 486 nm.

Example 1

Preparation of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0124 10 g of tris(2,3-epoxypropyl)isocyanurate (TEPIC-S (tradename): high purity product, manufactured by Nissan Chemical Industries, Ltd.), 9.2 g of carbon disulfide, 0.43 g of lithium bromide as a catalyst and 20 ml of tetrahydrofuran as a solvent were placed in a reaction flask equipped with a thermometer and a stirrer, and the resultant mixture was stirred at room temperature for 24 hours. Thereafter, the reaction mixture was placed in water, and a precipitate was filtrated and was washed with methanol. A crystal thus obtained was dried at 50 C. under vacuum to obtain 17.4 g of a pale yellow powder-like tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. A purity measured by HPLC was 93.4%. 0125 MASS (M): 525 (C15H15N3O6S6) 0126 1H-NMR(ppm, DMSO-d6): 3.74.0(m, 6H), 4.24.4(m, 6H), 5.35.5(m, 3H) 0127 Melting point ( C.): 196 (decomposition)

Example 2

Preparation of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0128 9.2 g of carbon disulfide, 0.43 of lithium bromide as a catalyst and 20 ml of tetrahydrofuran as a solvent were placed in a reaction flask equipped with a thermometer and a stirrer, and the resultant mixture was stirred at room temperature for about 5 minutes, and 10 g of tris(2,3-epoxypropyl)isocyanurate (TEPIC-S (tradename): high purity product, manufactured by Nissan Chemical Industries, Ltd.) was then slowly added into the reaction container for at least 1 hour, and after the addition, the resultant mixture was stirred at room temperature for 24 hours. After the reaction, the reaction mixture was poured into water, and a precipitate was filtrated and was washed with methanol. A crystal thus obtained was dried at 50 C. under vacuum to obtain 17.8 g of a pale yellow powder-like tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. A purity measured by HPLC was 97.3%. 0129 MASS (M): 525 (C15H15N3O6S6) 0130 1H-NMR(ppm, DMSO-d6): 3.74.0(m, 6H), 4.24.4(m, 6H), 5.35.5(m, 3H) 0131 Melting point ( C.): 197 (decomposition)

Example 3

Preparation of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0132 138.4 g of carbon disulfide, 6.45 g of lithium bromide as a catalyst and 300 ml of acetonitrile as a solvent were placed in a reaction flask equipped with a thermometer and a stirrer, and the resultant mixture was stirred at room temperature for about 5 minutes, and 150 g of tris(2,3-epoxypropyl)isocyanurate (TEPIC-S (tradename): high purity product, manufactured by Nissan Chemical Industries, Ltd.) was then slowly added into the reaction container for at least 5 hours, and after the addition, the resultant mixture was stirred at room temperature for 24 hours. After the reaction, the reaction mixture was poured into water, and a precipitate thus obtained was filtrated and was washed with methanol. A crystal thus obtained was dried at 50 C. under vacuum to obtain 265.1 g of a pale yellow powder-like tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. A purity measured by HPLC was 97.1%. 0133 MASS (M): 525 (C15H15N3O6S6) 0134 1 H-NMR (ppm, DMSO-d6): 3.74.0 (m, 6 H) 4.24.4 (m, 6 H), 5.35.5 (m, 3 H) 0135 Melting point ( C.): 197 (decomposition)

Example 4

Preparation of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0136 9.2 g of carbon disulfide, 0.21 g of lithium chloride as a catalyst and 20 ml of tetrahydrofuran as a solvent were placed in a reaction flask equipped with a thermometer and a stirrer, and the resultant mixture was stirred at room temperature for about 5 minutes, and 10 g of tris(2,3-epoxypropyl)isocyanurate (TEPIC-S (tradename): high purity product, manufactured by Nissan Chemical Industries, Ltd.) was then slowly added into the reaction container for at least 1 hour, and after the addition, the resultant mixture was stirred at room temperature for 24 hours. After finishing the reaction, the reaction mixture was poured into water, and a precipitate was filtrated and was washed with methanol. A crystal thus obtained was dried at 50 C. under vacuum to obtain 17.9 g of a pale yellow powder-like tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. A purity measured by HPLC was 98.1%. 0137 MASS (M): 525 (C15H15N3O6S6) 0138 1H-NMR(ppm, DMSO-d6): 3.74.0(m, 6H), 4.24.4 (m, 6H), 5.35.5(m, 3H) 0139 Melting point ( C.): 197 (decomposition)

Example 5

Preparation of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0140 9.2 g of carbon disulfide, 0.43 g of lithium bromide as a catalyst and 20 ml of methyl isobutyl ketone as a solvent were placed in a reaction flask equipped with a thermometer and a stirrer, and the resultant mixture was stirred at room temperature for about 5 minutes, and 10 g of tris(2,3-epoxypropyl)isocyanurate (TEPIC-S (tradename): high purity product, manufactured by Nissan Chemical Industries, Ltd.) was then slowly added into the reaction container for at least 1 hour, and after the addition, the resultant mixture was stirred at room temperature for 24 hours. After finishing the reaction, the reaction mixture was poured into water, and a precipitate was filtrated and was washed with methanol. A crystal thus obtained was dried at 50 C. under vacuum to obtain 17.3 g of a pale yellow powder-like tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. A purity measured by HPLC was 95.2%. 0141 MASS (M): 525 (C15H15N3O6S6) 0142 1H-NMR(ppm, DMSO-d6): 3.74.0(m, 6H), 4.24.4(m, 6H), 5.35.5(m, 3H) 0143 Melting point ( C.): 197 (decomposition)

Example 6

Preparation of tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0144 10 g of tris(2-methyl-2,3-epoxypropyl)isocyanurate (manufactured by Nissan Chemical Industries, Ltd.), 8.1 g of carbon disulfide, 0.38 g of lithium bromide as a catalyst and 20 ml of tetrahydrofuran as a solvent were placed in a reaction flask equipped with a thermometer and a stirrer, and the resultant mixture was stirred at room temperature for 24 hours. Thereafter, THF was distilled out from the reaction mixture at 50 C. under vacuum to obtain pale yellow tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. 0145 MASS(M): 567(C18H21N3O6S6)

Example 7

Preparation of tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0146 1.13 g of carbon disulfide, 6 ml of THF and 0.1 g of NaOMe methanol solution (28%) were placed in a reaction flask equipped with a thermometer and a stirrer. The resultant mixture was stirred at room temperature for 10 minutes, and 1.4 g of 1,3,5-tris(2-methyl-2,3-epoxypropyl)isocyanurate (manufactured by Nissan Chemical Industries, Ltd.), was added thereto, and the resultant mixture was stirred at room temperature for 3 days. After finishing the reaction, 20 ml of water was added thereto, and a solid was filtrated out and was fully washed with water, and a crystal thus obtained was dried at 50 C. under vacuum to obtain 2.3 g of a pale yellow solid of tris(5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. 0147 MASS (M): 567 (C18H21N3O6S6) 0148 1H-NMR(ppm, DMSO-d6): 1.6(s, 9H), 3.74.0(m, 6H), 4.24.4 (m, 6H)

Example 8

Preparation of high melting point type tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate (1:1 mixture of (1R,1R,1R)-tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and (1S,1S,1S)-tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate) 0149 10 g of high melting point type tris(2,3-epoxypropyl)isocyanurate (TEPIC-H (tradename): high purity product, manufactured by Nissan Chemical Industries, Ltd.), 9.2 g of carbon disulfide, 0.43 g of lithium bromide as a catalyst and 20 ml of tetrahydrofuran as a solvent were placed in a reaction flask equipped with a thermometer and a stirrer, and the resultant mixture was stirred at room temperature for 24 hours. Thereafter, the reaction mixture was poured into methanol, and a precipitate was filtrated and was washed with methanol. A crystal thus obtained was dried at 50 C. under vacuum to obtain 17.2 g of a pale yellow powder of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate. A purity measured by HPLC was 91.4%. 0150 MASS (M): 525(C15H15N3O6S6) 0151 Melting point ( C.): 223 (decomposition)

Example 9

Synthesis of trithiol isocyanurate compound (methylamine adduct of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate) and synthesis of polydisulfide film of oxidized cured material 0152 1 g of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained in Example 1 was suspended in 10 g of N-methyl-2-pyrrolidone, and 2 g of 40% methylamine-methanol solution was added thereto, and the mixture was stirred at room temperature for 30 minutes. The resultant reaction product was identified by mass spectrum, and it was recognized that methylamine 3 mol adduct of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate of 618 (C18H30N6O6S6, M) was formed. 0153 Thereafter, the colorless transparent reaction solution thus obtained was filtrated by 0.2 m diameter filter, and was spin-coated on a 4 inch silicon wafer at 2,500 rounds per minute for 1 minute, and was then heat-cured on a hot plate at 120 C. for 5 minutes. The cured product thus obtained was analyzed by IR spectrum, and it was recognized judging from disappearance of SH stretching vibration in the vicinity of 2,600-2,550 cm1 and CS stretching vibration based on thiocarbamate in the vicinity of 1,560 cm1 that a polydisulfide film of an oxidized cured material or trithiol isocyanurate compound was formed. The film thus obtained had a film thickness of about 800 , a refraction index (nD) of 1.62 and an Abbe number (D) of 33.

Example 10

Synthesis of trithiol isocyanurate compound (methylamine adduct of high melting point type tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate) and synthesis of polydisulfide film of oxidized cured material 0154 The same procedure as in Example 9 was repeated, except that the high melting point type tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate compound obtained in Example 8 was used as tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate starting material. The resultant reaction product was analyzed by mass spectrum, and it was recognized that methylamine 3 mol adduct of high melting point type tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate of 618(C18H30N6O6S6,M30 ) was formed. Thereafter, in the same manner as in Example 9, a polydisulfide film was synthesized, and its physical properties were measured. The film thus obtained had a film thickness of about 800 , a refraction index (nD) of 1.63 and an Abbe number of (D) of 24.

Example 11

Synthesis of trithiol isocyanurate compound by tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and butylamine 0155 1 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained in Example 1 was suspended in 10 g of tetrahydrofuran, and 0.5 g of butylamine was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was distilled off to obtain 1.45 g of a colorless foam-like compound. 0156 MASS (M): 744 (C27H48N6O6S6) 0157 1H-NMR(ppm, CDCl3): 0.81.0(t, 9H), 1.31.7(m, 12H), 1.8 6(bs, 3H), 2.73.0(m, 6H), 3.03.6(m, 6H),4.04.5(m, 6H), 5.56.1(m, 3H), 6.87.1(m, 3H)

Example 12

Synthesis of trithiol isocyanurate compound by tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and benzylamine 0158 5.26 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained in Example 1 was suspended in 10 ml of tetrahydrofuran, and 3.85 g of benzylamine was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was distilled off to obtain 8.95 g of a colorless foam-like compound. 0159 MASS (M): 846 (C36H42N6O6S6) 0160 1H-NMR (ppm, CDCl3): 1.71 (bs, 3 H), 2.6 2.9 (m, 6 H), 3.94.9 (m, 12 H), 5.65.9 (m, 3 H), 7.27.6 (m, 18 H)

Example 13

Synthesis of trithiol isocyanurate compound by tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and N-methylbenxylamine 0161 2.63 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained in Example 1 was suspended in 5 ml of tetrahydrofuran, and 1.84 g of N-methylbenzylamine was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was distilled off to obtain 4.5 g of a pale yellow foam-like compound. 0162 MASS (M): 888 (C39H48N6O6S6) 0163 1H-NMR (ppm, CDCl3): 1.62 (bs, 3 H) 2.73.4 (m, 15 H), 3.8 4.5 (m, 6 H), 4.55.2 (m, 6 H), 5.76.1 (m, 3 H), 7.17.5 (m, 15 H)

Example 14

Synthesis of trithiol isocyanurate compound by tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and allylamine 0164 2.1 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained in Example 1 was suspended in 5 ml of tetrahydrofuran, and 0.77 g of allylamine was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was distilled off to obtain 2.78 g of a colorless foam-like compound. 0165 MASS (M): 696 (C24H36N6O6S6) 0166 1H-NMR(ppm, CDCl3): 1.65(bs, 3H), 2.73.1(m, 6H), 3.74.6(m, 12H) 5.15.4(m, 6H) 5.66.1(m, 6H) 6.67.4(m, 3H)

Example 15

Synthesis of trithiol isocyanurate derivative by tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and 2-ethoxyethylamine 0167 1.05 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained in Example 1 was suspended in 5 ml of tetrahydrofuran, and 0.56 g of 2-ethoxyethylamine was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was distilled off to obtain 1.56 g of a pale yellow highly viscous compound. 0168 MASS (M): 792 (C27H48N6O9S6) 0169 1H-NMR (ppm, CDCl3): 1.20 (t, 9 H), 1.79 (bs, 3 H) 2.73.0 (m, 6 H) 3.43.9 (m, 18 H) 4.04.5 (m, 6 H), 5.66.1 (m, 3 H) 6.97.6 (m, 3 H)

Example 16

Synthesis of trithiol isocyanurate derivative by tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate and N,N-dimethylethylenediamine 0170 1.05 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate obtained in Example 1 was suspended in 5 ml of tetrahydrofuran, and 0.56 g of N,N-dimethylethylenediamine was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was distilled off to obtain 1.56 g of a colorless foam-like compound. 0171 MASS (M): 789 (C27H51N9O6S6) 0172 1H-NMR (ppm, CDCl3): 1.86 (bs, 3 H), 2.12.6 (m, 24 H), 2.73.1 (m, 6 H), 3.13.9 (m, 6 H), 3.94.6 (m, 6 H), 5.76.1 (m, 3 H) 7.78.4 (m, 3 H)

Application Example 1

Acetylation of benzylamine adduct of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0173 1.6 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate-benzylamine 3 mol adduct obtained in Example 12 was suspended in 10 ml of tetrahydrofuran, and 0.5 g of acetic anhydride and 0.5 g of pyridine were dropwise added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was distilled off, and solvent extraction with water and chloroform and concentration were carried out to obtain 2.64 g of a crude product. The crude product thus obtained was subjected to column (solvent: chloroform)-purification to obtain 1.73 g of a colorless foam-like aimed product. 0174 MASS (M): 972 (C42H48N6O9S6) 0175 1H-NMR (ppm, CDCl3): 1.65 (bs, 3 H), 2.22.4 (m, 9 H), 3.03.5 (m, 6 H), 3.84.9 (m, 1 2 H), 5.66.1 (m, 3 H) 7.27.4 (m, 15 H)

Application Example 2

Benzylation of benzylamine adduct of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0176 1.55 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate-benzylamine 3 mol adduct obtained in Example 12 was suspended in 15 ml of tetrahydrofuran, and 0.96 g of benzyl bromide and 1 ml of triethylamine were dropwise added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, an undissolved material was removed, and the reaction mixture was concentrated to obtain 2.0 g of a crude product. The crude product thus obtained was subjected to column (solvent: chloroform)-purification to obtain 1.4 g of a colorless foam-like aimed product. 0177 MASS (M): 972 (C42H48N6O9S6) 0178 1H-NMR (ppm, CDCl3): 2.52.9 (m, 6 H) 3.63.9 (m, 6 H), 3.94.8 (m, 12 H), 5.76.1 (m, 3 H), 7.17.6 (m, 33 H)

Application Example 3

Benzoylation of benzylamine adduct of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate 0179 0.86 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate-benzylamine 3 mol adduct obtained in Example 12 was suspended in 5 ml of tetrahydrofuran, and 0.42 g of benzoyl chloride and 0.6 ml of triethylamine were dropwise added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, an undissolved material was removed, and a crude product obtained by concentration was subjected to column (solvent: chloroform)-purification to obtain 1.1 g of a colorless foam-like aimed product. 0180 MASS (M): 1158 (C57H54N6O9S6) 0181 1 H-NMR (ppm, CDCl3): 3.23.7 (m, 6 H), 3.84.9 (m, 12 H), 5.86.1 (m, 3 H), 7.17.7 (m, 27 H), 7.78.1 (m, 6 H)

Application Example 4

Reaction of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate-benzylamine 3 mol adduct and phenyl isocyanate 0182 1.6 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate-benzylamine 3 mol adduct obtained in Example 12 was suspended in 5 ml of tetrahydrofuran, and 0.68 g of phenyl isocyanate was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the solvent was concentrated to obtain 2.48 g of a crude product. The crude product thus obtained was subjected to column (solvent: chloroform)-purification to obtain 1.93 g of a colorless foam-like aimed product. 0183 MASS (M): 1203 (C57H57N9O9S6) 0184 1H-NMR (ppm, CDCl3): 3.13.5 (m, 6 H), 3.94.8 (m, 12 H), 5.86.1 (m, 3 H), 7.07.6 (m, 36 H)

Application Example 5

Reaction of tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate-benzylamine 3 adduct and hexamethylene diisocyanate 0185 1.7 g of the tris(1,3-oxathiolane-2-thion-5-ylmethyl)isocyanurate-benzylamine 3 mol adduct obtained in Example 12 was suspended in 8 ml of tetrahydrofuran, and 0.5 g of hexamethylene diisocyanate was added thereto, and the resultant mixture was stirred at room temperature for 1 night in a nitrogen atmosphere. After finishing the reaction, the reaction mixture was poured into 50 ml of acetonitrile to carry out reprecipitation, and the precipitated material was dried to obtain 2.0 g of a white solid. 0186 Tg: 60 C., decomposition-initiation temperature: 203 C. (reduction of 5 wt %) 0187 Number average molecular weight (Mn): 2200 0188 Weight average molecular weight (Mw): 5900 0189 Polydispersity (Mw/Mn): 2.66 0190 According to the present invention, an isocyanurate compound having three 1,3-oxathiolane-2-thione rings in a molecular could be obtained, and a method for producing this isocyanurate compound was discovered. 0191 The isocyanurate compound having three 1,3-oxathiolane-2-thione rings in a molecule itself can be used as an additive to other material system to obtain an organic material having a high refractive index. Also, the isocyanurate compound of the present invention can be used as a crosslinking agent for polyamine, polyol, polythiol or the like, which is a reactive compound containing active hydrogen reactive with a 1,3-oxathiolane-2-thion-5-ylmethyl group or a 5-methyl-1,3-oxathiolane-2-thion-5-ylmethyl group which is a substituent site of the isocyanurate compound, and in this case also, an organic material having a high refractive index can be obtained. Further, not only by using the properties of this compound itself but also by using this compound as a curing agent or an additive, a material having a high refractive index can be provided since this compound has a large sulfur content to its molecular weight. 0192 The socyanurate compound of the first invention provides a trithiol isocyanurate compound by reacting with a compound having at least one functional group selected from the group consisting of a primary amine, a secondary amine, a hydroxyl group and a thiol group. The trithiol isocyanurate compound of the second invention is a compound having a thiol group in a side chain, and this compound can be used as a curing agent for a polyepoxy compound or a polyisocyanate compound. Also, when the trithiol isocyanurate compound is subjected to oxidation polymerization by oxygen, a cured film having a polydisulfide structure can be obtained. It has been discovered that this cured product provides an optically excellent material having a relatively high refractive index and a satisfactory Abbe number. 0193 On the other hand, it is possible to polymerize the isocyanurate compound alone in the presence of a catalyst of a basic material. 0194 The entire disclosures of Japanese Patent Application No. 2001-020907 filed on Jan. 30, 2001 and Japanese Patent Application No. 2001-237387 filed on Aug. 6, 2001 including specifications, claims and summaries are incorporated herein by reference in their entireties.