Episulfide composition, polymerizable composition, cured product, optical material, and lens

Abstract

This episulfide composition contains an optically-active compound A that includes one disulfide bond and two episulfide rings, and one of the two episulfide rings is an episulfide ring 1 that includes an asymmetric carbon atom C*1, and the other of the two episulfide rings is an episulfide ring 2 that includes an asymmetric carbon atom C*2. The optically-active compound A includes: at least one of a compound A-SS in which both C*1 and C*2 are S configurations and a compound A-RR in which both C*1 and C*2 are R configurations; and a compound A-RS in which one of C*1 and C*2 is an R configuration and the other is an S configuration. The ratio of the peak area RS of the compound A-RS to the total peak area T of the compound A-SS, the compound A-RR and the compound A-RS, as measured by HPLC, is 10-70% by area.

Description

Episulfide composition, polymerizable composition, cured product, optical material, and lens

[0001] The present disclosure relates to an episulfide composition, a polymerizable composition, a cured product, an optical material, and a lens.

[0002] Plastic lenses are lighter and less likely to break than inorganic lenses, and can be dyed, so in recent years they have rapidly become popular as optical materials for eyeglass lenses, camera lenses, and the like.

[0003] Among these, optical materials made of resins made from episulfide compounds are widely used because of their excellent refractive index and other properties (see, for example, Patent Document 1).

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2002-194083

[0005] Incidentally, there are cases where it is required to further suppress haze in a cured product obtained using an episulfide compound and an optical material containing the cured product.

[0006] The present disclosure has been made in view of the above circumstances. An object of the present disclosure is to provide an episulfide composition and a polymerizable composition from which a cured product with reduced haze can be obtained, as well as a cured product, an optical material, and a lens with reduced haze.

[0007] Means for solving the above problems include the following embodiments: <1> An episulfide composition containing an optically active compound A, wherein the optically active compound A contains one disulfide bond and two episulfide rings, one of the two episulfide rings having an asymmetric carbon atom C ＊１ and the other is an episulfide ring 1 containing an asymmetric carbon atom C ＊２ and the optically active compound A is an episulfide ring 2 containing the asymmetric carbon atom C ＊１ and the asymmetric carbon atom C ＊２ and an optically active compound A-SS, wherein each of the asymmetric carbon atoms C ＊１ and the asymmetric carbon atom C ＊２ and at least one of the optically active compounds A-RR, in which each of the asymmetric carbon atoms C＊１ and the asymmetric carbon atom C ＊２ and an optically active compound A-RS, one of which is an R-isomer and the other is an S-isomer, wherein the ratio of a peak area RS of the optically active compound A-RS to a total peak area T of the optically active compound A-SS, the optically active compound A-RR, and the optically active compound A-RS, as measured by high performance liquid chromatography, is 10 area% to 70 area%. <2> The episulfide composition according to <1>, wherein the ratio of the peak area RS to the total peak area T is more than 50 area% and not more than 70 area%. <3> The episulfide composition according to <1>, wherein the ratio of the peak area RS to the total peak area T is 10 area% to 50 area%. <4> The episulfide composition according to any one of <1> to <3>, wherein the optically active compound A comprises a compound represented by the following formula (A1):

[0008]

[0009] In formula (A1), R １Ａ ~R ７Ａ are each independently a hydrogen atom or an optionally substituted monovalent hydrocarbon group, m is an integer of 0 to 3, C ＊１Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊１ and C ＊２Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊２ There are multiple R １Ａ ~R ７Ａ and m may be the same or different.

[0010] <5> The episulfide composition according to any one of <1> to <4>, wherein the content of the optically active compound A is 90 mass% or more based on the total amount of the episulfide composition. <6> A polymerizable composition comprising the episulfide composition according to any one of <1> to <5> and a polymerization catalyst. <7> The polymerizable composition according to <6>, which is used for producing an optical material. <8> A cured product of the polymerizable composition according to <6>. <9> An optical material comprising the cured product of the polymerizable composition according to <6>. <10> A lens comprising the cured product of the polymerizable composition according to <6>.

[0011] According to the present disclosure, there are provided an episulfide composition and a polymerizable composition that can give a cured product with reduced haze, as well as a cured product, an optical material, and a lens with reduced haze.

[0012] In the present disclosure, a numerical range expressed using "to" means a range that includes the numerical values ​​written before and after "to" as the lower and upper limits. In the present disclosure, when a composition contains multiple substances corresponding to each component, the amount of each component refers to the total amount of the multiple substances present in the composition, unless otherwise specified. In the numerical ranges described in stages in the present disclosure, the upper or lower limit described in one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in the numerical ranges described in the present disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the examples.

[0013] [Episulfide composition] The episulfide composition of the present disclosure is an episulfide composition containing an optically active compound A, wherein the optically active compound A contains one disulfide bond and two episulfide rings, one of which has an asymmetric carbon atom C ＊１ and the other is an episulfide ring 1 containing an asymmetric carbon atom C ＊２ and the optically active compound A is an episulfide ring 2 containing an asymmetric carbon atom C ＊１ and the asymmetric carbon atom C ＊２ and an optically active compound A-SS in which all of the asymmetric carbon atoms C ＊１and the asymmetric carbon atom C ＊２ and at least one of optically active compounds A-RR, in which each of the above is an R-configuration, and an asymmetric carbon atom C ＊１ and the asymmetric carbon atom C ＊２ and an optically active compound A-RS, one of which is an R-configuration and the other an S-configuration, wherein the ratio of the peak area RS of the optically active compound A-RS to the total peak area T of the optically active compound A-SS, the optically active compound A-RR, and the optically active compound A-RS (hereinafter also referred to as the peak area ratio [RS / T]) measured by high performance liquid chromatography is 10 area % to 80 area %.

[0014] According to the episulfide composition of the present disclosure, a cured product with reduced haze can be obtained. It is believed that the effect of reducing haze in the cured product is contributed to by a peak area ratio [RS / T] of 80 area% or less. It is believed that a peak area ratio [RS / T] of 10 area% or more contributes to the curability and handleability of the episulfide composition.

[0015] <Optical Active Compound A> The episulfide composition of the present disclosure contains optically active compound A. Optically active compound A is a compound containing one disulfide bond and two episulfide rings. That is, optically active compound A is a compound encompassed within the concept of an episulfide compound (i.e., a compound containing an episulfide ring).

[0016] One of the two episulfide rings in the optically active compound A has an asymmetric carbon atom C ＊１ and the other is an episulfide ring 1 containing an asymmetric carbon atom C ＊２ The optically active compound A is an episulfide ring 2 containing an asymmetric carbon atom C ＊１ and the asymmetric carbon atom C ＊２ and an optically active compound A-SS in which all of the asymmetric carbon atoms C ＊１ and the asymmetric carbon atom C ＊２ and at least one of optically active compounds A-RR, in which each of the above is an R-configuration, and an asymmetric carbon atom C ＊１ and the asymmetric carbon atom C ＊２and an optically active compound A-RS, one of which is an R-configuration and the other is an S-configuration.

[0017] In the present disclosure, an asymmetric carbon atom in the R configuration means an asymmetric carbon atom in the R configuration, and an asymmetric carbon atom in the S configuration means an asymmetric carbon atom in the S configuration.

[0018] Asymmetric carbon atom C in optically active compound A ＊１ and the asymmetric carbon atom C ＊２ The optically active compound A-RS, in which one of the two is an R-configuration and the other is an S-configuration, is preferably a meso-configuration. The optically active compound A-RS is a meso-configuration when the asymmetric carbon atom C ＊１Ａ is an S-configuration and the asymmetric carbon atom C ＊２Ａ is an R-configuration, and a compound having an asymmetric carbon atom C ＊２Ａ is an R-configuration and the asymmetric carbon atom C ＊２Ａ This means that a compound in which the S-form is the same compound as the S-form is the same compound.

[0019] As described above, the optically active compound A includes at least one of the optically active compound A-SS and the optically active compound A-RR. It is more preferable that the optically active compound A includes both the optically active compound A-SS and the optically active compound A-RR.

[0020] The optically active compound A preferably includes a compound represented by the following formula (A1).

[0021]

[0022] In formula (A1), R １Ａ ~R ７Ａ are each independently a hydrogen atom or an optionally substituted monovalent hydrocarbon group, m is an integer of 0 to 3, C ＊１Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊１ and C ＊２Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊２ There are multiple R １Ａ ~R ７Ａ and m may be the same or different.

[0023] In formula (A1), R１Ａ ~R ７Ａ Examples of the optionally substituted monovalent hydrocarbon group represented by each of the formulas (A1) include a halogen atom, a thiol group (i.e., a mercapto group), an alkoxy group, an alkylthio group, and a hydroxyl group. １Ａ ~R ７Ａ The number of carbon atoms in the optionally substituted monovalent hydrocarbon group represented by each of the following formulas is preferably 1 to 10, more preferably 1 to 6, even more preferably 1 to 3, still more preferably 1 or 2, and even more preferably 1, as the total number of carbon atoms including the carbon atoms of the substituent when the group has a substituent. １Ａ ~R ７Ａ The "optionally substituted monovalent hydrocarbon group" represented by each of the formulas (A1) and (B) is preferably an alkyl group having 1 to 6 carbon atoms (i.e., an unsubstituted alkyl group), more preferably an alkyl group having 1 to 3 carbon atoms, even more preferably a methyl group or an ethyl group, and even more preferably a methyl group. １Ａ ~R ７Ａ It is particularly preferred that each of is a hydrogen atom.

[0024] In formula (A1), m is an integer of 0 to 3. m is preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 1.

[0025] In formula (A1), C ＊１Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊１ and C ＊２Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊２ It is. C ＊１Ａ and C ＊２Ａ Each of the carbon atoms may be an asymmetric carbon atom of S configuration or an asymmetric carbon atom of R configuration. The optically active compound A is a compound represented by formula (A1), ＊１Ａ and C ＊２Ａ and a compound (A1SS) represented by formula (A1), wherein all of the following are S-configurations: ＊１Ａ and C ＊２Ａand at least one (more preferably both) of the compounds (A1RR) in which all of the following are R-configurations, and a compound represented by formula (A1), ＊１Ａ and C ＊２Ａ It is more preferable that the compound (A1RS) contains one of the compounds in the R-configuration and the other in the S-configuration.

[0026] The content of the optically active compound A is preferably 80% by mass or more, and more preferably 90% by mass or more, based on the total amount of the episulfide composition.

[0027] The total content of the optically active compound A-SS, the optically active compound A-RR, and the optically active compound A-RS is preferably 80% by mass or more, and more preferably 90% by mass or more, based on the total amount of the episulfide composition.

[0028] The total content of the compound (A1SS), the compound (A1RR), and the compound (A1RS) is preferably 80% by mass or more, and more preferably 90% by mass or more, based on the total amount of the episulfide composition.

[0029] <Peak Area Ratio [RS / T]> In the episulfide composition of the present disclosure, the peak area ratio [RS / T] (i.e., the ratio of the peak area RS of the optically active compound A-RS to the total peak area T of the optically active compound A-SS, the optically active compound A-RR, and the optically active compound A-RS, as measured by high performance liquid chromatography) is 10 area% to 70 area%.

[0030] The conditions for measuring the peak area ratio [RS / T] by high performance liquid chromatography (HPLC) are as shown in the Examples below.

[0031] In the episulfide composition of the present disclosure, when the peak area ratio [RS / T] is 70 area% or less, haze in a cured product of the episulfide composition of the present disclosure is suppressed. In the episulfide composition of the present disclosure, when the peak area ratio [RS / T] is 10 area% or more, curability and handleability of the episulfide composition of the present disclosure are improved.

[0032] In the present disclosure, the concept of a cured product of the episulfide composition of the present disclosure encompasses not only a cured product obtained by curing only the episulfide composition of the present disclosure, but also a cured product obtained by curing a polymerizable composition of the present disclosure described below (i.e., a polymerizable composition comprising the episulfide composition of the present disclosure and a polymerization catalyst). Furthermore, in the present disclosure, the concept of curability of the episulfide composition of the present disclosure encompasses not only the curability of the episulfide composition of the present disclosure alone, but also the curability of a polymerizable composition of the present disclosure described below (i.e., a polymerizable composition comprising the episulfide composition of the present disclosure and a polymerization catalyst).

[0033] As described above, the peak area ratio [RS / T] may be 10 area% to 70 area%. From the viewpoint of further improving the maximum bending stress of the cured product of the episulfide composition, the peak area ratio [RS / T] is preferably 20 area% to 70 area%, more preferably 50 area% to 70 area%, and even more preferably more than 50 area% but not more than 70 area%.

[0034] The peak area ratio [RS / T] may be 10 area% to 50 area%.

[0035] <Other Components> The episulfide composition of the present disclosure may contain other components in addition to the optically active compound A. Examples of other components include a reaction solvent used in the synthesis of the optically active compound A, reaction by-products (impurities) generated by the synthesis, and the like.

[0036] <Applications> There are no particular limitations on the applications of the episulfide composition of the present disclosure. The episulfide composition of the present disclosure can be used to produce a cured product of an episulfide compound (specifically, optically active compound A) that can have a high refractive index, and is therefore suitable for use, for example, in producing optical materials. Optical materials will be described later.

[0037] [Polymerizable composition] The polymerizable composition of the present disclosure contains the episulfide composition of the present disclosure described above and a polymerization catalyst. The polymerizable composition of the present disclosure has excellent polymerizability because it contains the episulfide composition of the present disclosure described above.

[0038] <Polymerization Catalyst> The polymerizable composition of the present disclosure contains a polymerization catalyst. The polymerization catalyst contained in the polymerizable composition may be one type or two or more types.

[0039] Examples of the polymerization catalyst include a tertiary amine compound, a phosphine compound, a Lewis acid, a radical polymerization catalyst, a cationic polymerization catalyst, etc. For the polymerization catalyst, reference can be made to the description in paragraphs 0029 to 0033 of JP-A No. 2002-194083, for example.

[0040] The polymerization catalyst is preferably a tertiary amine compound or a phosphine compound. Examples of tertiary amine compounds include triethylamine, tri-n-butylamine, tri-n-hexylamine, N,N-diisopropylethylamine, triethylenediamine, triphenylamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N,N-dibutylethanolamine, triethanolamine, N-ethyldiethanolamine, N,N-dimethylbenzylamine, N,N-diethylbenzylamine, tribenzylamine, N-methyldibenzylamine, N,N-dimethylcyclohexylamine, N,N-dicyclohexylmethylamine, N,N-diethylcyclohexylamine, N,N-dicyclohexylethylamine, N,N-dimethylbutylamine, N,N-dicyclohexylbutylamine, N-methylmorpholine, N-isopropylmorpholine, pyridine, quinoline, N,N-dimethylaniline, N,N-diethylaniline, Examples of the amine compound include α-picoline, β-picoline, γ-picoline, 2,2'-bipyridyl, 1,4-dimethylpiperazine, tetramethylethylenediamine, hexamethylenetetramine, 1,8-diazabicyclo(5,4,0)-7-undecene, and 2,4,6-tris(N,N-dimethylaminomethyl)phenol.

[0041] Examples of the phosphine compound include trimethylphosphine, triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, tribenzylphosphine, 1,2-bis(diphenylphosphino)ethane, and 1,2-bis(dimethylphosphino)ethane.

[0042] The content of the polymerization catalyst in the polymerizable composition of the present disclosure is preferably 0.01% by mass to 5% by mass, more preferably 0.01% by mass to 2% by mass, and even more preferably 0.03% by mass to 1% by mass, relative to the total amount of the polymerizable composition.

[0043] <Thiol Compound> The polymerizable composition of the present disclosure preferably further contains a thiol compound. When the polymerizable composition of the present disclosure contains a thiol compound, a resin (i.e., a cured product) can be obtained by polymerizing the episulfide compound (A) and the episulfide compound (B) in the episulfide composition with the thiol compound. The obtained resin may have better resin properties. When the polymerizable composition of the present disclosure contains a thiol compound, the thiol compound contained may be only one type, or two or more types.

[0044] The thiol compound includes an aliphatic thiol, an aromatic thiol, and the like.

[0045] Aliphatic thiols include pentaerythritol tetrakis(2-mercaptothioglycolate), pentaerythritol tetrakis(3-mercaptopropionate), trimethylolpropane tris(2-mercaptothioglycolate), trimethylolpropane tris(3-mercaptopropionate), 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 2,5-dimercaptomethyl-1,4-dithiane, 2,5-bis[(2-mercaptoethyl)thiomethyl]-1,4-dithiane, 1,3-cyclohexanedithiol, 1,4-cyclohexanedithiol, bis(mercaptomethyl)sulfide, bis(mercaptomethyl)disulfide, bis(mercaptoethyl)sulfide, bis(mercaptoethyl)disulfide, At least one selected from the group consisting of 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and tetrakis(mercaptomethylthio)propane is preferred, although the aliphatic thiol is not limited to these specific examples.

[0046] The aromatic thiol is preferably at least one selected from the group consisting of benzylthiol, xylylenedithiol, 1,3-bis(mercaptoethyl)benzene, 1,4-bis(mercaptoethyl)benzene, 2,5-toluenedithiol, 3,4-toluenedithiol, thiophenol, 1,2-dimercaptobenzene, 1,3-dimercaptobenzene, 1,4-dimercaptobenzene, and 1,2-bis(mercaptomethyl)benzene. However, the aromatic thiol is not limited to these specific examples.

[0047] The thiol compound is preferably a compound having two or more thiol groups (i.e., mercapto groups) (hereinafter also referred to as a "polythiol compound").

[0048] Furthermore, when the polymerizable composition of the present disclosure contains a thiol compound, the thiol compound preferably contains an aliphatic polythiol (i.e., an aliphatic thiol that is a polythiol compound). In this case, the proportion of the aliphatic polythiol in the total amount of thiol compounds is preferably 50% by mass, more preferably 60% by mass or more, and even more preferably 80% by mass or more. There is no particular upper limit for the proportion of the aliphatic thiol. The proportion of the aliphatic thiol may be 100% by mass, less than 100% by mass, 99% by mass or less, or 95% by mass or less.

[0049] The thiol compound more preferably contains at least one selected from the group consisting of 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (hereinafter also referred to as "polythiol A"). In this case, the proportion of polythiol A in the total amount of thiol compounds is preferably 50% by mass, more preferably 60% by mass or more, and even more preferably 80% by mass or more. There is no particular upper limit to the proportion of polythiol A. The proportion of the polythiol A may be 100% by mass, less than 100% by mass, 99% by mass or less, or 95% by mass or less.

[0050] The thiol compound more preferably contains at least one selected from the group consisting of 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (hereinafter also referred to as "polythiol A1"). In this case, the proportion of polythiol A1 in the total amount of thiol compounds is preferably 50% by mass, more preferably 60% by mass or more, and even more preferably 80% by mass or more. There is no particular upper limit to the proportion of polythiol A1. The proportion of polythiol A1 may be 100% by mass, less than 100% by mass, 99% by mass or less, or 95% by mass or less.

[0051] When the episulfide composition of the present disclosure contains a thiol compound, the content of the thiol compound is preferably 1% by mass to 50% by mass, more preferably 2% by mass to 30% by mass, even more preferably 3% by mass to 20% by mass, and still more preferably 5% by mass to 15% by mass, relative to the total amount of the specific episulfide compound.

[0052] For thiol compounds, reference may be made to paragraph 0039 of WO 2018 / 079829.

[0053] <Other Components> The polymerizable composition of the present disclosure may contain other components in addition to the components described above. Examples of the other components include isocyanate compounds, epoxy compounds, alcohol compounds (e.g., polyol compounds), mercapto organic acids, resins (e.g., acrylic resins, olefin resins, etc.), crosslinking agents, light stabilizers, UV absorbers, antioxidants, coloring inhibitors, dyes, fillers, and internal mold release agents. Known components can be used as the other components. For details of the other components, see, for example, JP 2002-194083 A.

[0054] <Applications> There are no particular limitations on the applications of the polymerizable composition of the present disclosure. The polymerizable composition of the present disclosure can produce a cured product that can have a high refractive index, and is therefore suitable for use in, for example, producing optical materials. Optical materials will be described later.

[0055] [Cured Product] The cured product of the present disclosure is a cured product of the polymerizable composition of the present disclosure. The cured product of the present disclosure can be obtained, for example, by polymerizing the monomers in the polymerizable composition of the present disclosure (e.g., the episulfide compound (A) and the episulfide compound (B), or the episulfide compound (A), the episulfide compound (B), and a thiol compound, etc.) to thereby cure the polymerizable composition of the present disclosure. In this case, the cured product of the present disclosure includes a resin obtained by polymerizing the monomers in the polymerizable composition of the present disclosure. The obtained resin has excellent resin specificity.

[0056] There are no particular limitations on the method for polymerizing the monomer in the polymerizable composition of the present disclosure (i.e., the method for producing the cured product of the present disclosure). Examples of methods for polymerizing the monomer in the polymerizable composition of the present disclosure include cast polymerization. In cast polymerization, the polymerizable composition of the present disclosure is first poured between molds held together by a gasket, tape, or the like. If necessary, degassing, filtration, or the like may be performed during this process. Next, the monomer in the polymerizable composition poured between the molds is polymerized, thereby curing the polymerizable composition between the molds to obtain a cured product. The cured product is then removed from the mold to obtain a cured product. Polymerization of the monomer may be performed by heating the polymerizable composition of the present disclosure. This heating can be performed, for example, using a heating device equipped with a mechanism for heating an object to be heated in an oven, water, or the like.

[0057] The polymerization conditions (e.g., polymerization temperature, polymerization time, etc.) for polymerizing the monomers in the polymerizable composition of the present disclosure are appropriately set in consideration of the composition, the type and amount of monomers used in the composition, the type and amount of polymerization catalyst used in the composition, the shape of the mold, etc. Examples of the polymerization temperature include −50° C. to 150° C., 10° C. to 150° C., etc. Examples of the polymerization time include 1 hour to 200 hours, 1 hour to 80 hours, etc.

[0058] The cured product of the present disclosure may be obtained by subjecting the monomer to polymerization followed by treatment such as annealing, etc. Annealing temperatures include 50°C to 150°C, 90°C to 140°C, and 100°C to 130°C.

[0059] The cured product of the present disclosure may have a high refractive index because it is a cured product of a polymerizable composition containing an episulfide compound. The refractive index (nd) of the cured product of the present disclosure is preferably 1.71 or more, more preferably 1.72 or more, and even more preferably 1.73 or more.

[0060] Furthermore, by changing the molding mold used during cast polymerization, cured products of various shapes can be obtained. Therefore, the cured products of the present disclosure can be suitably used, for example, as materials for optical materials such as eyeglass lenses, camera lenses, and light-emitting diodes (LEDs); materials for transparent resin members; and the like.

[0061] [Optical Material] The optical material (e.g., a lens; the same applies hereinafter) of the present disclosure includes the cured product of the present disclosure. The optical material of the present disclosure may consist of the cured product of the present disclosure, or may include the cured product of the present disclosure and other elements. Examples of other elements include other members and a coating layer provided on the cured product of the present disclosure.

[0062] The optical material of the present disclosure contains a cured product of an episulfide composition and therefore can have a high refractive index. The refractive index (nd) of the optical material of the present disclosure is preferably 1.71 or more, more preferably 1.72 or more, and even more preferably 1.73 or more.

[0063] Optical materials of the present disclosure include eyeglass lenses, camera lenses, polarized lenses, light-emitting diodes (LEDs), and the like.

[0064] - Eyeglass Lens - Hereinafter, an eyeglass lens will be described as an example of the optical material of the present disclosure. The eyeglass lens includes the cured product of the present disclosure molded into a desired lens shape. The eyeglass lens preferably further includes a coating layer provided on one or both sides of the cured product.

[0065] Specific examples of the coating layer include a primer layer, a hard coat layer, an antireflection layer, an antifogging coat layer, an antifouling layer, and a water-repellent layer. Each of these coating layers can be used alone, or multiple coating layers can be used in combination. When coating layers are applied to both sides of the cured product, the same coating layer or different coating layers can be applied to each side.

[0066] The components of the coating layer can be appropriately selected depending on the purpose, and examples of the components of the coating layer include resins (e.g., urethane resins, epoxy resins, polyester resins, melamine resins, polyvinyl acetal resins, etc.), infrared absorbers, light stabilizers, antioxidants, photochromic compounds, dyes, pigments, and antistatic agents.

[0067] For details about eyeglass lenses and coating layers, reference can be made to the descriptions in publicly known documents such as JP 2002-194083 A and WO 2017 / 047745 A, as appropriate.

[0068] Examples of the present disclosure are shown below, but the present disclosure is not limited to the following examples. Hereinafter, "%" means % by mass. "(SS)", "(RR)", and "(RS)" mean a combination of S- and S-isomers, a combination of R- and R-isomers, and a combination of R- and S-isomers, respectively.

[0069] [Production of composition 1 containing episulfide compound (A1-1) as the main component] In this production example, using racemic epichlorohydrin as a starting material, composition 1 containing episulfide compound (A1-1) (hereinafter also simply referred to as "(A1-1)") as the main component was produced as the target product. Here, (A1-1) is a mixture of the RR form (hereinafter referred to as "(A1-1RR)"), the SS form (hereinafter referred to as "(A1-1SS)"), and the RS form (hereinafter referred to as "(A1-1RS)"). (A1-1RR) is an example of optically active compound A, and more specifically, ＊１ and the asymmetric carbon atom C ＊２(A1-1SS) is an example of an optically active compound A, and more specifically, in formula (A1), ＊１ and the asymmetric carbon atom C ＊２ (A1-1RS) is an example of an optically active compound A, and more specifically, in formula (A1), ＊１ and the asymmetric carbon atom C ＊２ is an example of a compound in which one of the compounds is an R-configuration and the other is an S-configuration.

[0070]

[0071] A production example of composition 1 containing (A1-1) as the main component will be described in detail below.

[0072] <Synthesis of Intermediate a1, Racemic 3-chloro-1-mercapto-2-propanol> The starting materials, racemic epichlorohydrin and H ２ S to produce racemic 3-chloro-1-mercapto-2-propanol, intermediate a1 (see reaction scheme below).

[0073]

[0074] The detailed procedure is as follows. A reaction flask equipped with a stirrer, thermometer, gas inlet tube, and condenser was charged with racemic epichlorohydrin (462.4 g; 5.00 mol), methanol (800 ml), and a 48% by mass aqueous solution of NaSH (6.0 g; the amount of NaSH was 2.9 g). The internal temperature was maintained at 0 to 5°C with stirring. Hydrogen sulfide gas (277.5 g; 7.500 mol) was blown into the reaction system through the gas inlet tube over 2 hours, and the mixture was aged at 5°C for 3 hours, thereby reacting epichlorohydrin and hydrogen sulfide to obtain a reaction solution. After removing the methanol from the resulting reaction solution, the concentrate was subjected to Smith distillation, and intermediate a1 (i.e., racemic 3-chloro-1-mercapto-2-propanol) with a purity of 99% was obtained from the distillate side.

[0075] <Synthesis of Intermediate b1, a Racemic Halohydrin Compound> Using the intermediate a1 obtained above as a starting material, intermediate b1, a racemic halohydrin compound, was obtained (see the following reaction scheme).

[0076]

[0077] The detailed procedure is as follows: Pure water (445.1 g), sodium bicarbonate (380.8 g), and methanol (123.6 g) were added to the intermediate a1 (553.9 g; 4.330 mol) obtained above, and bromine (362.1 g; 2.266 mol) was added dropwise to the mixture over 10 hours while stirring under a nitrogen atmosphere while maintaining the internal temperature at 10° C. The resulting liquid was aged by continuing to stir for 1 hour while maintaining the internal temperature at 10° C., to obtain a reaction liquid containing intermediate b1.

[0078] <Synthesis of Intermediate c1, a Racemic Epoxy Compound> Using the intermediate c1 obtained above as a starting material, intermediate c1, a racemic epoxy compound, was obtained (see the following reaction scheme).

[0079]

[0080] The detailed procedure is described below. Toluene (93.4 g) was added to the reaction solution containing intermediate b1 obtained above, and while stirring, the internal temperature was maintained at 10°C. To this, 25% by mass aqueous NaOH solution (824.2 g; 5.151 mol) was added dropwise over 3 hours. Stirring was continued for another 3 hours while maintaining the internal temperature at 10°C, and the mixture was aged. Next, pure water (203.3 g) was added to the reaction solution, and the mixture was stirred for 15 minutes, allowing the mixture to separate into an organic layer and an aqueous layer. The aqueous layer was then discharged. To the remaining organic layer, 13% by mass aqueous NaCl solution (71.2 g) was added and the mixture was stirred, allowing the mixture to separate into an organic layer and an aqueous layer. Acetic acid was then added while stirring until the pH of the aqueous layer reached 5 to 6. The aqueous layer was then discharged. The remaining organic layer was concentrated under reduced pressure to obtain a crude product (365.3 g; purity 97.6%) containing racemic bis(2,3-epoxypropyl) disulfide (i.e., intermediate c1).

[0081] <Synthesis of Intermediate d1, which is a Racemic Thiuronium Salt> Intermediate d1, which is a racemic thironium salt, was synthesized by converting the above-mentioned intermediate c1 into a thiuronium salt.

[0082]

[0083] The detailed procedure is described below. In a separate flask, 72.0 g (1.2 mol) of acetic acid, 313.0 g (4.111 mol) of thiourea, 684.1 g of pure water, and 533.3 g of methanol were added to form a bed solution. While the internal temperature was maintained at 15° C., a crude product containing the intermediate c1 (365.3 g; 2.000 mol as the amount of intermediate c1) was added dropwise from dropping funnel 1, and 88% by mass formic acid (157.0 g) was added dropwise from dropping funnel 2 over 5 hours. After completion of these additions, the mixture was stirred for an additional 3 hours while maintaining the internal temperature at 15° C., yielding a reaction solution containing intermediate d1, which is a racemic thioronium salt.

[0084] <Production of a crude product containing episulfide compound (A1-1)> A crude product containing episulfide compound (A1-1) (hereinafter, also referred to as "crude (A1-1)") was produced using a reaction solution containing the above-mentioned intermediate d1 (see the following reaction scheme).

[0085]

[0086] The detailed procedure is described below. Methyl isobutyl ketone (MIBK) (760.7 g) was charged all at once into a flask containing the reaction solution containing the intermediate d1. Then, 10% by mass aqueous ammonia (679.7 g; 3.991 mol as the amount of ammonia) was added dropwise thereto over 2 hours, and the mixture was aged with stirring for another 2 hours while maintaining the internal temperature at 10°C. The resulting liquid was allowed to stand, separated, and the aqueous layer was discarded. The remaining organic layer was washed with 1056.7 g of a 13% by mass aqueous NaCl solution and 6 g of 10% by mass aqueous ammonia, and then washed with 13% by mass aqueous NaCl solution (1056.7 g), acetic acid (11.9 g), and methanol (126.7 g). The washed organic layer was concentrated under reduced pressure to obtain a crude product containing episulfide compound (A1-1) (hereinafter also referred to as crude (A1-1)) (393.3 g).

[0087] <Purification (Production of Composition 1 Comprising Episulfide Compound (A1-1) as the Main Component)> The crude (A1-1) described above was subjected to column purification to obtain a composition 1 comprising a purified episulfide compound (A1-1) as the main component and containing trace amounts of impurities.

[0088]

[0089] The detailed procedure is as follows. The above-mentioned crude (A1-1) was dissolved in a large amount of methylcyclohexane, and some components that were not completely dissolved were removed. The obtained solution of (A1-1) was passed through a silica gel column for purification. The silica gel column fraction was concentrated and subjected to a low-boiling point removal treatment, thereby obtaining Composition 1 containing purified (A1-1) as the main component and trace amounts of impurities.

[0090] [Separation of composition 1 containing (A1-1) as the main component (production of crystalline composition and liquid composition)] The composition 1 containing (A1-1) as the main component obtained above was separated into a crystalline composition containing (A1-1RR) and (A1-1SS) as the main components, and a liquid composition containing (A1-1RS) as the main component. The detailed procedures are described below.

[0091] Composition 1 obtained above was placed in a transparent glass bottle and stored in a refrigerator at 5°C for one week to allow crystallization. After storage, Composition 1 was in a clear liquid state in the upper part and in a state where white crystals had settled in the lower part. After storage, Composition 1 was separated by decantation into the upper supernatant liquid and the lower crystalline part.

[0092] The crystalline portion was placed in ethyl acetate cooled to below -25°C and slowly sludged. Then, the stirring was stopped and the mixture was placed in a freezer at -25°C for 24 hours (hereinafter, the operation up to this point is referred to as "ethyl acetate sludge"). The slurry after ethyl acetate sludge was then quickly filtered, and the crystalline portion remaining as a filter cake was recovered. The ethyl acetate sludge and filtration procedures were repeated two more times for the recovered crystalline portion. The crystalline portion thus obtained, which had been subjected to the ethyl acetate sludge and filtration procedures three times in total, was dried in a desiccator under high vacuum for 24 hours to obtain a crystalline composition containing (A1-1RR) and (A1-1SS) as major components. The optical isomer ratio of (A1-1) in the crystalline composition was analyzed as described below.

[0093] On the other hand, the supernatant was concentrated under reduced pressure and further subjected to a low-boiling point removal treatment to obtain a liquid composition containing (A1-1RS) as a main component. The optical isomer ratio of (A1-1) in the liquid composition was analyzed as described below.

[0094] [Analysis of Optical Isomer Ratio in Crystalline Composition and Liquid Composition] (A1-1) in the crystalline composition and (A1-1) in the liquid composition were analyzed by high performance liquid chromatography (HPLC) under the following measurement conditions. The results are shown in Table 1.

[0095] - HPLC measurement conditions - Column: Daicel Chemical Co., Ltd. Optical resolution column AD-H φ0.46 cm x 25 cm x 2 in series Mobile phase: Hexane: Isopropyl alcohol (IPA) = 98:2 (volume ratio) Flow rate: 0.7 ml / min Oven temperature: 29°C Measurement wavelength: 215 nm

[0096]

[0097] As shown in Table 1, the total peak area T (= peak area RS + peak area RR + peak area SS), peak area RR + peak area SS, and peak area RS were determined for (A1-1) in the crystalline composition and (A1-1) in the liquid composition. Specifically, in the analysis results for the crystalline composition, the peak area RR + peak area SS was large, confirming that the main components in the crystalline composition were (A1-1RR) and (A1-1SS). On the other hand, in the analysis results for the liquid composition, the peak area RS was large, confirming that the main component in the liquid composition was (A1-1RS).

[0098] [Examples 1 to 3 and Comparative Example 1] <Production of Episulfide Compositions> The above-mentioned crystalline composition and the above-mentioned liquid composition were appropriately blended to obtain the episulfide compositions of Examples 1 to 3 and Comparative Example 1 shown in Table 2. The conditions for component analysis of each episulfide composition were the same as the conditions for component analysis performed on the crystalline composition and the liquid composition, respectively.

[0099] <Production of Polymerizable Composition> Polymerizable compositions were prepared using the episulfide compositions of Examples 1 to 3 and Comparative Example 1 as follows. Dicyclohexylmethylamine (15 mg) and dimethylcyclohexylamine (3 mg) as polymerization catalysts, and TINUVIN PS (manufactured by BASF Japan) (0.165 g) as an ultraviolet absorber were placed in a conical beaker. Any one of the episulfide compositions of Examples 1 to 3 and Comparative Example 1 (15,000 g) was placed therein, and the mixture was stirred and mixed. After confirming that TINUVIN PS had dissolved through this stirring and mixing, a mixture (1.500 g) of 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane [polythiol composition] was added and mixed to obtain a polymerizable composition.

[0100] <Production of Cured Product (Resin Molded Product)> The polymerizable composition obtained above was filtered through a TEFE filter with a retention particle size of 3 μm. The resulting filtrate (i.e., the polymerizable composition) was subjected to vacuum degassing at 15°C to 25°C for 1 hour. The vacuum-degassed polymerizable composition was poured between a pair of glass molds secured with tape. The "pair of glass molds secured with tape" used were those used to prepare 2 mm flat plates. The pair of glass molds into which the polymerizable composition had been poured were then placed in an oven. The temperature inside the oven was first maintained at 30°C for 10 hours, then increased from 30°C to 120°C over 8 hours, then maintained at 120°C for 2 hours, and then decreased from 120°C to 60°C over 1 hour. Through the above process, the monomers (i.e., the episulfide compound and the polythiol compound) in the polymerizable composition were polymerized, and a cured product of the polymerizable composition (i.e., a resin molded product) was formed between the pair of glass molds. Thereafter, the resin molded body was released from the pair of glass molds to obtain a 2 mm thick flat plate-shaped resin molded body as a cured product of the polymerizable composition.

[0101] <Evaluation> (Haze of cured product) The haze of the cured product obtained above (i.e., a 2 mm thick flat resin molded product) was measured using an NDH2000 (Nippon Denshoku Industries Co., Ltd.) in accordance with JIS K7361-1 "Test method for total light transmittance of plastic transparent materials," JIS K7105 "Test method for optical properties of plastics," and JIS K7136 "Determination of haze of plastic - transparent materials." Based on the haze obtained, the haze of the cured product was evaluated according to the following evaluation criteria. The results are shown in Table 2. In the evaluation criteria below, the rank A is the rank in which the haze of the cured product is most suppressed.

[0102] -Evaluation criteria for haze of cured product- A: Haze is less than 3 B: Haze is 3 or more but less than 20 C: Haze is 20 or more

[0103] (Maximum bending stress of cured product) For Examples 1 to 3, in addition to the evaluation of the haze of the cured product described above, the maximum bending stress of the cured product was also evaluated. Test pieces measuring 65 mm in length and 25 mm in width were cut from the cured products obtained above (i.e., 2 mm thick flat resin molded products), and the cut surfaces of the cut test pieces were polished with a No. 800 file to obtain flat test pieces measuring 65 mm in length, 25 mm in width, and 2 mm in thickness. A three-point bending test was performed on the obtained flat test pieces using an autograph (manufactured by Shimazu Corporation), with the width of the base on which the flat test piece was placed during measurement set to 34 mm. The maximum bending stress in this three-point bending test was determined, and the maximum bending stress was evaluated based on the following evaluation criteria. The results are shown in Table 2. In the evaluation criteria below, the cured product with the best maximum bending stress was ranked AA.

[0104] -Evaluation criteria for maximum bending stress of cured product- AA: Maximum bending stress is 125 N / mm ２ A: Maximum point stress is 100 N / mm or more ２ 125N / mm or more ２ B: Maximum point stress is less than 90 N / mm ２ More than 100N / mm ２ C: Maximum point stress is less than 90 N / mm ２ is less than

[0105]

[0106] As shown in Table 2, the haze of the cured product was suppressed in Examples 1 to 3, which used episulfide compositions having a peak area ratio [RS / T] of 10 area% to 70 area%. In contrast, the haze of the cured product could not be suppressed in Comparative Example 1, in which the peak area ratio [RS / T] exceeded 70 area%.

[0107] Of Examples 1 to 3, Example 1, in which the peak area ratio [RS / T] was more than 50 area % and not more than 70 area %, exhibited superior maximum bending stress of the cured product.

[0108] The disclosure of Japanese Patent Application No. 2023-009655, filed on January 25, 2023, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. An episulfide composition containing an optically active compound A, wherein the optically active compound A contains one disulfide bond and two episulfide rings, one of which has an asymmetric carbon atom C ＊１ and the other is an episulfide ring 1 containing an asymmetric carbon atom C ＊２ and the optically active compound A is an episulfide ring 2 containing the asymmetric carbon atom C ＊１ and the asymmetric carbon atom C ＊２ and an optically active compound A-SS, wherein each of the asymmetric carbon atoms C ＊１ and the asymmetric carbon atom C ＊２ and at least one of the optically active compounds A-RR, in which each of the asymmetric carbon atoms C ＊１ and the asymmetric carbon atom C ＊２ an optically active compound A-RS, one of which is an R-configuration and the other is an S-configuration, wherein the ratio of a peak area RS of the optically active compound A-RS to a total peak area T of the optically active compound A-SS, the optically active compound A-RR, and the optically active compound A-RS, as measured by high performance liquid chromatography, is 10 area % to 70 area %.

2. The episulfide composition according to claim 1, wherein the ratio of the peak area RS to the total peak area T is more than 50 area% and not more than 70 area%.

3. The episulfide composition according to claim 1, wherein the ratio of the peak area RS to the total peak area T is 10 area% to 50 area%.

4. The episulfide composition according to any one of claims 1 to 3, wherein the optically active compound A comprises a compound represented by the following formula (A1): [In formula (A1), R １Ａ ~R ７Ａ are each independently a hydrogen atom or an optionally substituted monovalent hydrocarbon group, m is an integer of 0 to 3, C ＊１Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊１ and C ＊２Ａ represents the asymmetric carbon atom C in the compound represented by formula (A1). ＊２ There are multiple R １Ａ ~R ７Ａ and m may be the same or different.

5. The episulfide composition according to any one of claims 1 to 3, wherein the content of the optically active compound A is 90 mass % or more based on the total amount of the episulfide composition.

6. A polymerizable composition comprising the episulfide composition according to any one of claims 1 to 3 and a polymerization catalyst.

7. The polymerizable composition according to claim 6, which is used in the production of an optical material.

8. A cured product of the polymerizable composition according to claim 6.

9. An optical material comprising a cured product of the polymerizable composition according to claim 6.

10. A lens comprising a cured product of the polymerizable composition according to claim 6.