Polythiol composition and application thereof

Abstract

Provided is a polythiol composition containing a polythiol component (A) that is at least one selected from the group consisting of polythiol compounds represented by formula (A) and a thioamide component (B) that is at least one selected from the group consisting of thioamide compounds represented by formula (B). The peak area ratio [thioamide component (B) / polythiol component (A)] measured by high-performance liquid chromatography is 3 area% or less. In formula (A) and formula (B), R1 represents a C1-30 (m+n)-valent organic group, and n and m each independently represent an integer of 1-8.

Description

Polythiol composition and its applications 【0001】 This disclosure relates to polythiol compositions and their applications. 【0002】 Plastic lenses, which contain resin, are lighter, less prone to breakage, and can be dyed compared to inorganic lenses, and have therefore become rapidly popular in recent years for applications such as eyeglass lenses and camera lenses. 【0003】 Thiourethane resin is known as one of the resins used for lenses. Patent documents 1 and 2 disclose a method for producing polythiol compounds, which are one of the raw materials for thiourethane resin, and a polymerizable composition for optical materials (for example, a polymerizable composition for lenses) containing the polythiol compound. Patent documents 3 and 4 also disclose a polythiol composition containing a polythiol compound as a polythiol composition that can produce lenses of excellent quality. Patent documents 3 and 4 also disclose a polymerizable composition for optical materials (for example, a polymerizable composition for lenses) containing the polythiol composition. 【0004】 Patent Document 1: International Publication No. 2014 / 027427 Patent Document 2: International Publication No. 2014 / 027428 Patent Document 3: International Publication No. 2016 / 010065 Patent Document 4: International Publication No. 2020 / 41183 【0005】 In some cases, a reduction in yellowness may be required for resins manufactured using polythiol compositions containing polythiol compounds. 【0006】 One embodiment of this disclosure aims to solve the problem of providing a polythiol composition and its applications that can produce a resin with reduced yellowness. 【0007】The means for solving the above problems include the following embodiments: <1> A polythiol composition comprising: a polythiol component (A) selected from the group consisting of polythiol compounds represented by the following formula (A); and a thioamide component (B) selected from the group consisting of thioamide compounds represented by the following formula (B), wherein the peak area ratio [thioamide component (B) / polythiol component (A)] measured by high-performance liquid chromatography is 3 area % or less. 【0008】 【0009】 In equations (A) and (B), R １ The symbol represents an organic group with 1 to 30 carbon atoms and an (m+n) valency, where n is an integer from 1 to 8 and m is an integer from 0 to 8. 【0010】 <2> R in formula (A) and formula (B) １ The polythiol composition described in <1>, wherein the group contains the following structure (RS1). 【0011】 【0012】 In the structure (RS1), the eight asterisks (*) each represent a bond location. 【0013】 <3> R in formula (A) and formula (B) １However, the residue obtained by removing (m+n) mercapto groups from 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, the residue obtained by removing (m+n) mercapto groups from 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, the residue obtained by removing (m+n) mercapto groups from 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, the residue obtained by removing (m+n) mercapto groups from 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, the residue obtained by removing (m+n) mercapto groups from 2,5-bismercaptomethyl-1,4-dithiane, or A polythiol composition according to <1> or <2>, wherein the residue is obtained by removing (m+n) mercapto groups from bis(2-mercaptoethyl) sulfide. <4> A polythiol composition according to any one of <1> to <3>, wherein the peak area ratio [thioamide component (B) / polythiol component (A)] is 0.001 area% or more. <5> A polymerizable composition comprising the polythiol composition according to any one of <1> to <4>, and a polyiso(thio)cyanate compound. <6> A polymerizable composition according to <5>, further comprising thiol compound XS, which is a thiol compound other than the polythiol component (A).<7> The thiol compound XS is methanedithiol, 1,2-ethanedithiol, 1,2,3-propanetrithiol, pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), tetrakis(mercaptomethylthiomethyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, bis(2-mercaptoethyl)sulfide The polymerizable composition according to <6>, which is at least one selected from the group consisting of bis(2,3-dimercaptopropyl) sulfide, 2,5-dimercaptomethyl-1,4-dithiane, 2,5-dimercapto-1,4-dithiane, 2,5-dimercaptomethyl-2,5-dimethyl-1,4-dithiane, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, and 4,6-bis(mercaptomethylthio)-1,3-dithiane. <8> The polymerizable composition according to any one of <5> to <7>, wherein the polyiso(thio)cyanate compound comprises at least one selected from the group consisting of pentamethylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, bis(isocyanatomethyl)cyclohexane, bis(isocyanatocyclohexyl)methane, 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and phenylene diisocyanate.<9> A polyiso(thio)cyanate composition comprising the polyiso(thio)cyanate compound, wherein the polyiso(thio)cyanate composition comprises xylylene diisocyanate and at least one selected from the group consisting of the following compound (N1), the following compound (N2), and the following compound (N3), wherein if the polyiso(thio)cyanate composition comprises compound (N1), the peak area of ​​compound (N1) in gas chromatography measurement is 0.20 ppm or more relative to the peak area of ​​xylylene diisocyanate, and if the polyiso(thio)cyanate composition comprises compound (N2), the peak area of ​​compound (N2) in gas chromatography measurement is 0.05 ppm or more relative to the peak area of ​​xylylene diisocyanate. The polymerizable composition according to any one of <5> to <8>, wherein, when the polyiso(thio)cyanate composition contains the compound (N3), the peak area of ​​the compound (N3) in gas chromatography measurement is 0.10 ppm or more relative to the peak area of ​​xylylene diisocyanate (1). 【0014】 【0015】<10> A resin containing a cured product of the polymerizable composition according to any one of <5> to <9>. <11> A molded article containing the resin according to <9>. <12> An optical material containing the resin according to <9>. <13> A lens containing the resin according to <9>. <14> A process for producing the polythiol composition according to any one of <1> to <4>, the method comprising: preparing a raw material composition containing the polythiol component (A) and the thioamide component (B); and reacting the raw material composition in the presence of a basic compound to obtain the polythiol composition. <15> The method for producing a polythiol composition according to <14>, wherein the basic compound contains an amine compound having a pKa in the range of 4 to 12. <16> The method for producing a polythiol composition according to <14> or <15>, wherein the basic compound contains an amine compound containing at least one of a primary amino group and a secondary amino group. <17> The method for producing a polythiol composition according to any one of <14> to <16>, wherein the step of preparing the raw material composition includes reacting an isothiouronium salt (1) represented by the following formula (1) in the presence of a sulfur-containing compound (2) represented by the following formula (2) to obtain the raw material composition. 【0016】 【0017】 In formula (1), R １ represents a (m + n)-valent organic group having 1 to 30 carbon atoms, R ２ , R ３ , and R ４ each independently represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, n represents an integer of 1 to 8, m represents an integer of 0 to 8, and X represents a halogen atom. When there are a plurality of R ２ in formula (1), the plurality of R ２ may be the same or different. When there are a plurality of R ３ in formula (1), the plurality of R ３ may be the same or different. When there are a plurality of R ４ in formula (1), the plurality of R ４X may be the same or different, and if there are multiple X in equation (1), the multiple X may be the same or different. In equation (2), M １ These are alkali metal atoms, alkaline earth metal atoms, or NH ４ ＋ Here, m1 represents an integer between 1 and 3, n1 represents an integer between 1 and 3, and k represents an integer between 0 and 3. 【0018】 <18> A method for producing a thiol compound according to <17>, comprising the steps of: reacting a compound (Px) represented by the following formula (Px) with a thiourea compound (4) represented by the following formula (4) to produce the isothiouronium salt (1); and reacting the isothiouronium salt (1) in the presence of the sulfur-containing compound (2) to obtain the raw material composition. 【0019】 【0020】 In formula (Px), R Ｘ represents an organic group with 1 to 30 carbon atoms and an (m+n) valency, where n is an integer from 1 to 8, m is an integer from 0 to 8, and A represents a hydroxyl group or a halogen atom. If there are multiple A's in formula (Px), the multiple A's may be the same or different. In formula (4), R ２ , R ３ , and R ４ Each of these independently represents either a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms. 【0021】 <19> A method for producing a polythiol composition according to any one of <14> to <18>, comprising the step of preparing the raw material composition, wherein the step of reacting an isothiouronium salt (1) represented by the following formula (1) with a sulfur-containing compound (2) represented by the following formula (2) and at least one selected from the group consisting of a basic compound (3) represented by the following formula (3), a basic compound (X) represented by the following formula (X), and ammonia, to obtain the raw material composition. 【0022】 In formula (1), R １ R represents an organic group with 1 to 30 carbon atoms and an (m+n) valency.２ , R ３ , and R ４ Each of these independently represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, n represents an integer from 1 to 8, m represents an integer from 0 to 8, and X represents a halogen atom. In formula (1), R ２ If multiple R ２ They may be the same or different, and R in equation (1) ３ If multiple R ３ They may be the same or different, and R in equation (1) ４ If multiple R ４ X may be the same or different, and if there are multiple X in equation (1), the multiple X may be the same or different. In equation (2), M １ These are alkali metal atoms, alkaline earth metal atoms, or NH ４ ＋ In equation (3), M ２ These are alkali metal atoms, alkaline earth metal atoms, or NH ４ ＋ In equation (X), M ３ 'r' represents an alkali metal atom or alkaline earth metal atom, r represents an integer between 1 and 2, and s represents an integer between 0 and 1. 【0023】 <20> A method for producing a thiol compound according to <19>, comprising the steps of: reacting a compound (Px) represented by the following formula (Px) with a thiourea compound (4) represented by the following formula (4) to produce the isothiouronium salt (1); and reacting the isothiouronium salt (1) with the sulfur-containing compound (2) and at least one selected from the group consisting of the basic compound (3), the basic compound (X), and ammonia to obtain the raw material composition. 【0024】 【0025】 In formula (Px), RＸ represents an organic group with 1 to 30 carbon atoms and an (m+n) valency, where n is an integer from 1 to 8, m is an integer from 0 to 8, and A represents a hydroxyl group or a halogen atom. If there are multiple A's in formula (Px), the multiple A's may be the same or different. In formula (4), R ２ , R ３ , and R ４ Each of these independently represents either a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms. 【0026】 According to one aspect of this disclosure, a polythiol composition and its applications are provided that can produce a resin with reduced yellowness. 【0027】 In this disclosure, numerical ranges expressed using "~" mean a range that includes the numbers before and after "~" as the lower and upper limits. In this disclosure, the term "process" includes not only independent processes but also processes that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved. In this disclosure, the amount of each component in a composition means the total amount of multiple substances present in the composition, unless otherwise specified, if there are multiple substances corresponding to each component in the composition. In numerical ranges described in steps in this disclosure, the upper or lower limit stated in one numerical range may be replaced with the upper or lower limit of another numerical range described in steps. Also, in numerical ranges described in this disclosure, the upper or lower limit of that numerical range may be replaced with the values ​​shown in the examples. In this disclosure, "*" in a chemical formula means a bond position. 【0028】 [Polythiol Composition] The polythiol composition of this disclosure contains a polythiol component (A) which is at least one selected from the group consisting of polythiol compounds represented by the following formula (A), and a thioamide component (B) which is at least one selected from the group consisting of thioamide compounds represented by the following formula (B), wherein the peak area ratio [thioamide component (B) / polythiol component (A)] measured by high-performance liquid chromatography is 3 area % or less. 【0029】 【0030】 In equations (A) and (B), R １ The symbol represents an organic group with 1 to 30 carbon atoms and an (m+n) valency, where n is an integer from 1 to 8 and m is an integer from 0 to 8. 【0031】 As mentioned above, in some cases, a reduction in the yellowness (YI (Yellow Index)) of resins produced using a polythiol composition containing a polythiol compound is required. For example, when the reaction of an isothiouronium salt to produce the above-mentioned polythiol component (A) is carried out in the presence of a sulfur-containing compound (e.g., NaSH), a thioamide component (B) may be produced as a reaction byproduct along with the polythiol component (A). When a resin is produced using these polythiol component (A) and thioamide component (B), the YI of the resulting resin may be high (see, for example, Comparative Example 2 described later). The YI of the resin is thought to be due to the thioamide component (B). In this regard, the polythiol composition of this disclosure makes it possible to produce a resin with reduced yellowness. The reason why this effect is obtained is thought to be that the peak area ratio [thioamide component (B) / polythiol component (A)] is reduced to 3 area % or less. 【0032】 The following describes the components that may be contained in the polythiol composition of this disclosure. 【0033】 <Polythiol component (A)> The polythiol composition of this disclosure contains polythiol component (A). Polythiol component (A) is at least one selected from the group consisting of polythiol compounds represented by the above formula (A). 【0034】 In formula (1), R １ In the monovalent organic group with 1 to 30 carbon atoms represented by , the number of carbon atoms is preferably 1 to 10. 【0035】 R １ The group is preferably a group containing a hydrogen atom, a carbon atom, and a sulfur atom, and more preferably a group containing the following structure (RS1). For example, the polythiol compound represented by formula (A) preferably contains a mercaptoethylthio group. 【0036】 【0037】 In the structure (RS1), the eight asterisks (*) each represent a bond location. 【0038】 R １ The molecular weight of the group represented is preferably 100 to 500, more preferably 150 to 350, and even more preferably 150 to 300. 【0039】 R １ This is a residue obtained by removing (m+n) mercapto groups from 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, a residue obtained by removing (m+n) mercapto groups from 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, a residue obtained by removing (m+n) mercapto groups from 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, a residue obtained by removing (m+n) mercapto groups from 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, a residue obtained by removing (m+n) mercapto groups from 2,5-bismercaptomethyl-1,4-dithiane, or It is preferable that the residue is obtained by removing (m+n) mercapto groups from bis(2-mercaptoethyl) sulfide, more preferably that the residue is obtained by removing (m+n) mercapto groups from 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, a residue obtained by removing (m+n) mercapto groups from 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, a residue obtained by removing (m+n) mercapto groups from 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, or a residue obtained by removing (m+n) mercapto groups from 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane. It is particularly preferable that the residue is obtained by removing (m+n) mercapto groups from 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane. 【0040】In formula (A), n represents an integer from 1 to 8, and m represents an integer from 0 to 8. In formula (A), m + n (i.e., the sum of m and n) is preferably an integer from 2 to 8, more preferably an integer from 2 to 4, even more preferably an integer from 3 to 4, and even more preferably 3. 【0041】 The polythiol compound represented by formula (A) contained in the polythiol component (A) may be one type or two or more types. The polythiol compound represented by formula (A) is preferably polythiol A1, which is 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane; polythiol A2, which is 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; 2,5-bismercaptomethyl-1,4-dithiane; or bis(2-mercaptoethyl) sulfide, with polythiol component A1 or polythiol component A2 being more preferred, and polythiol component A1 being particularly preferred. 【0042】 <Thiamide component (B)> The polythiol composition of this disclosure contains a thioamide component (B). The thioamide component (B) is at least one selected from the group consisting of thioamide compounds represented by the above formula (B). 【0043】 In formula (B), R １ n and m are, respectively, R in equation (A). １ It is synonymous with n and m, and the preferred embodiment is the same. 【0044】<Peak Area Ratio [Thioamide Component (B) / Polythiol Component (A)]> The polythiol composition of this disclosure has a peak area ratio [Thioamide Component (B) / Polythiol Component (A)] (hereinafter also simply referred to as the peak area ratio [Thioamide Component (B) / Polythiol Component (A)]) of 3 area or less, as measured by high-performance liquid chromatography. This reduces the YI of the resin produced using the polythiol composition of this disclosure. The peak area ratio [Thioamide Component (B) / Polythiol Component (A)] is preferably 2 area or less, more preferably 0.6 area or less, and even more preferably 0.4 area or less. The lower limit of the peak area ratio [Thioamide Component (B) / Polythiol Component (A)] is, for example, 0.001 area, 0.005 area, 0.01 area, 0.05 area, etc. 【0045】 The analytical conditions for high-performance liquid chromatography (HPLC) are as follows: 【0046】 -HPLC Analysis Conditions- • Machine: Shimadzu HPLC Detector: SPD-10Avp Pump: LC-10ADvp Thermostat: CTO-10Avp • Column: Mightysil RP-18 Aqua 250-4.6 (5μm) • Mobile Phase: 0.1mol-KH ２ PO ４ A liquid obtained by adjusting the pH of an aqueous solution to 3 with phosphoric acid. • Flow rate: 0.9 mL / min • Temperature bath: 40°C • Detector: UV 220 nm 【0047】 <Compound (XB)> The polythiol composition of this disclosure may also contain the following compound (XB). Compound (XB) is a compound obtained by replacing at least one of the mercapto groups in the polythiol component (A) described above with a group represented by the following formula (XB-1). 【0048】 【0049】 In equation (XB-1), * indicates a bonding position. 【0050】Examples of compound (XB) are shown below, but compound (XB) is not limited to these examples. 【0051】 【0052】 <Compound (C1)> The polythiol composition of this disclosure may contain the following compound (C1). 【0053】 【0054】 In compound (C1), X is -CH ２ - Or represents a sulfur atom. 【0055】 <Other Components> The polythiol compositions of this disclosure may contain at least one other component other than those described above (for example, other thiol compounds, components other than thiol compounds, etc.). An example of other thiol compounds is thiol compound XS, which may be contained in the polymerizable composition described later. 【0056】 <Method for Producing Polythiol Composition> The polythiol composition of the present disclosure described above can be produced, for example, by adjusting the production conditions when producing the polythiol component (A) and adjusting the composition of the polythiol composition (in particular, the peak area ratio [thioamide component (B) / polythiol component (A)]). Alternatively, the polythiol composition of the present disclosure may be produced by mixing two or more raw material compositions with different peak area ratios [thioamide component (B) / polythiol component (A)] in a proportion such that the peak area ratio [thioamide component (B) / polythiol component (A)] is 3 area or less (see Example 1, etc.). Alternatively, the polythiol composition of the present disclosure may be produced by the following production method X, which includes a base treatment to reduce the peak area ratio [thioamide component (B) / polythiol component (A)] (see, for example, Example 101). 【0057】<Method for producing a polythiol composition including base treatment (Method X)> The method for producing a polythiol composition including base treatment (Method X) includes the steps of: preparing a raw material composition containing a polythiol component (A) and a thioamide component (B); and reacting the raw material composition in the presence of a basic compound to obtain the polythiol composition of the present disclosure described above. 【0058】 According to manufacturing method X, by reacting the raw material composition in the presence of a basic compound (i.e., performing a basic treatment), the peak area ratio [thioamide component (B) / polythiol component (A)] in the raw material composition can be reduced, and as a result, a polythiol composition of the present disclosure having a peak area ratio [thioamide component (B) / polythiol component (A)] of 3 area % or less can be produced. This is thought to be because, by reacting the raw material composition in the presence of a basic compound, a polythiol component (A) is generated from a portion of the thioamide component (B) in the raw material composition. 【0059】 (Step to prepare the raw material composition) The step to prepare the raw material composition in manufacturing method X is the step to prepare a raw material composition containing a polythiol component (A) and a thioamide component (B). The step to prepare the raw material composition may be a step to prepare a pre-manufactured raw material composition, or it may be a step to manufacture the raw material composition. 【0060】 The step of preparing the raw material composition preferably includes reacting an isothiuronium salt (1) represented by the following formula (1) in the presence of a sulfur-containing compound (2) represented by the following formula (2) to obtain the raw material composition. 【0061】 【0062】 In formula (1), R １ R represents an organic group with 1 to 30 carbon atoms and an (m+n) valency. ２ , R ３ , and R ４ Each of these independently represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, n represents an integer from 1 to 8, m represents an integer from 0 to 8, and X represents a halogen atom. In formula (1), R ２If multiple R ２ They may be the same or different, and R in equation (1) ３ If multiple R ３ They may be the same or different, and R in equation (1) ４ If multiple R ４ X may be the same or different, and if there are multiple X in equation (1), the multiple X may be the same or different. In equation (2), M １ These are alkali metal atoms, alkaline earth metal atoms, or NH ４ ＋ Here, m1 represents an integer from 1 to 3, n1 represents an integer from 1 to 3, and k represents an integer from 0 to 3. 【0063】 When an isothiouronium salt (1) is reacted in the presence of a sulfur-containing compound (2), a polythiol component (A), which is the main product, and a thioamide component (B), which is a by-product, may be produced. 【0064】 Furthermore, when the isothiouronium salt (1) is reacted in the presence of a sulfur-containing compound (2), a thiourea compound (4) represented by formula (4), described later, may also be produced as a by-product. In this case, for example, the reaction of the isothiouronium salt (1) yields an organic layer containing a raw material composition comprising a polythiol component (A), which is the main product, and a thioamide component (B), which is a by-product, and an aqueous layer containing the thiourea compound (4). As described later, the thiourea compound (4) is used in the production of the isothiouronium salt (1). Therefore, the method of reacting the isothiouronium salt (1) in the presence of a sulfur-containing compound (2) has the advantage that the thiourea compound (4) can be recycled. 【0065】 -Isothiouronium salt (1)- Isothiouronium salt (1) is the salt represented by the above formula (1). 【0066】 In formula (1), R １ n and m are, respectively, R in equation (A). １ It is synonymous with n and m, and the preferred embodiment is the same. 【0067】In formula (1), R ２ , R ３ , and R ４ Each of these independently represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms. ２ , R ３ , or R ４ The number of carbon atoms in the monovalent organic group having 1 to 10 carbon atoms, represented by R, is preferably 1 to 6, and more preferably 1 to 3. ２ , R ３ , or R ４ The monovalent organic group represented by is preferably an aliphatic group which may contain a heteroatom, an alicyclic group which may contain a heteroatom, or an aromatic group which may contain a heteroatom, more preferably an alkyl group, and even more preferably a methyl group or an ethyl group. 【0068】 R ２ , R ３ , and R ４ Each of these is independently preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (more preferably 1 to 6, even more preferably 1 to 3 carbon atoms), more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom. 【0069】 In formula (1), X represents a halogen atom. The halogen atom represented by X is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, with a chlorine atom being more preferred. 【0070】 -Sulfur-containing compound (2)- Sulfur-containing compound (2) is a compound represented by the following formula (2). In the process of preparing the raw material composition, only one type of sulfur-containing compound (2) may be used, or two or more types may be used. 【0071】 【0072】 In formula (2), M １ These are alkali metal atoms, alkaline earth metal atoms, or NH ４ ＋ Here, m1 represents an integer from 1 to 3, n1 represents an integer from 1 to 3, and k represents an integer from 0 to 3. 【0073】 In formula (2), M １represents an alkali metal atom, an alkaline earth metal atom, or NH ４ ＋ . 【0074】 M １ As the alkali metal atom represented by, preferably, it is a Li atom, a Na atom, or a K atom, and more preferably a Na atom. 【0075】 M １ As the alkaline earth metal atom represented by, preferably, it is a Mg atom or a Ca atom. 【0076】 M １ As, preferably, it is an alkali metal atom, an alkaline earth metal atom, or NH ４ ＋ , more preferably an alkali metal atom, still more preferably a Li atom, a Na atom, or a K atom, and still more preferably a Na atom. 【0077】 In formula (2), m1 represents an integer of 1 to 3. As m1, preferably, it is 1 or 2, and more preferably 1. 【0078】 In formula (2), n1 represents an integer of 1 to 3. As n1, preferably, it is 1 or 2, and more preferably 1. 【0079】 In formula (2), the sum of m1 and n1 is preferably 2 or 3. 【0080】 In formula (2), k represents an integer of 0 to 3. As k, preferably, it is an integer of 0 to 2, and more preferably 0 or 1. 【0081】 Specific examples of the sulfur-containing compound (2) include NaSH, Na ２ S, KSH, K ２ S, Ca(SH) ２ , CaS, Li ２ S, LiSH, (NH ４ ) ２ S, (NH ４ )SH, etc. 【0082】 The charged amount of the sulfur-containing compound (2) is preferably 90 mol% to 200 mol% with respect to the charged amount of the isothiouronium salt (1). 【0083】 In the step of preparing the raw material composition, it is preferable to use an aqueous solution of the sulfur-containing compound (2). The concentration of the aqueous solution can be adjusted as appropriate. 【0084】 - At least one selected from the group consisting of the basic compound (3), the basic compound (X), and ammonia - In the step of preparing the raw material composition, it is preferable to react the isothiouronium salt (1) in the presence of the sulfur-containing compound (2) and at least one selected from the group consisting of the basic compound (3), the basic compound (X), and ammonia to obtain the raw material composition. 【0085】 The basic compound (3) is a compound represented by the following formula (3). When the basic compound (3) is used, the basic compound (3) used may be only one kind or two or more kinds. 【0086】 【0087】 In formula (3), M ２ represents an alkali metal atom, an alkaline earth metal atom, or NH ４ ＋ p represents an integer from 1 to 2, and q represents an integer from 1 to 2. 【0088】 M ２ As the alkali metal atom represented by, preferably, a Li atom, a Na atom, or a K atom, more preferably a Na atom. 【0089】 M ２ As the alkaline earth metal atom represented by, preferably, a Mg atom or a Ca atom. 【0090】 M ２ is preferably an alkali metal atom or NH ４ ＋ and more preferably a Na atom or NH ４ ＋ is. 【0091】 In formula (3), p represents an integer from 1 to 2. As p, preferably 1. 【0092】In equation (3), q represents an integer between 1 and 2. Preferably, q is 1. 【0093】 Specific examples of basic compounds (3) include NaOH and NH. ４ Examples include OH (i.e., aqueous ammonia), etc. 【0094】 Basic compound (3), basic compound (X), and ammonia (NH ３ The total amount of (1) added is preferably 10 mol% to 200 mol% relative to the amount of isothiouronium salt (1) added. 【0095】 When using basic compound (3) in the process of preparing the raw material composition, it is preferable to use an aqueous solution of basic compound (3). The concentration of the aqueous solution can be adjusted as appropriate. 【0096】 Basic compound (X) is a compound represented by the following formula (X). When using basic compound (X), only one basic compound (X) or two or more basic compounds (X) may be used. 【0097】 【0098】 In formula (X), M ３ 'r' represents an alkali metal atom or alkaline earth metal atom, r represents an integer between 1 and 2, and s represents an integer between 0 and 1. 【0099】 A preferred embodiment of the basic compound (X) is M ３ A configuration in which is an alkali metal atom, r is 1, and s is 1 (i.e., alkali metal bicarbonate), M ３ A configuration in which is an alkali metal atom, r is 2, and s is 0 (i.e., an alkali metal carbonate), and M ３ This is an embodiment in which is an alkaline earth metal atom, r is 1, and s is 0 (i.e., an alkaline earth metal carbonate). 【0100】 A specific example of a basic compound (X) is NaHCO3. ３ Na ２ CO ３ , KHCO ３ _K ２ CO ３ , MgCO ３ CaCO３ Examples include, etc. 【0101】 When using a basic compound (X) in the reaction step, it is preferable to use an aqueous solution of the basic compound (X). The concentration of the aqueous solution can be adjusted as appropriate. 【0102】 - Addition format of isothiouronium salt (1), sulfur-containing compound (2), and "at least one selected from the group consisting of basic compound (3), basic compound (X), and ammonia" - When a raw material composition is obtained by reacting isothiouronium salt (1) with sulfur-containing compound (2) and at least one selected from the group consisting of basic compound (3), basic compound (X), and ammonia in the process of preparing the raw material composition, there are no particular restrictions on the addition format of isothiouronium salt (1), sulfur-containing compound (2), and "at least one selected from the group consisting of basic compound (3), basic compound (X), and ammonia," and they can be selected as appropriate. Examples of addition formats include the following addition formats 1 to 4. (Addition Method 1) An isothiuronium salt reaction mass (hereinafter also referred to as "ITU salt mass") is charged into the reactor, and then a sulfur-containing compound (2) and "at least one selected from the group consisting of basic compound (3), basic compound (X), and ammonia" (hereinafter also simply referred to as "base") are added thereto (corresponding to addition method (1) in the example). (Addition Method 2) The sulfur-containing compound (2) and the base are charged into the reactor, and then the ITU salt mass is added thereto (corresponding to addition method (2) in the example). (Addition Method 3) The base is charged into the reactor, and then the sulfur-containing compound and the ITU salt mass are added thereto. (Addition Method 4) The sulfur-containing compound, the base, and the ITU salt mass are simultaneously added dropwise to the reactor. In addition methods 1 to 3 above, a portion of each component may be charged into the reactor and the remainder added later. Also, in addition method 1, the base may be added in portions. In this case, the base added in portions may be the same or different. An example of adding the base in a divided manner in addition method 1 is to first charge the reactor with ITU salt mass and a portion of the base to be used (e.g., NaOH), and then add the sulfur-containing compound (2) and the remainder of the base to be used (e.g., NH4). ４An example of adding OH is given. 【0103】 -Reaction solvent (organic solvent)- The above reaction of isothiouronium salt (1) may be carried out in the presence of a reaction solvent or in the absence of a reaction solvent (i.e., under conditions where no reaction solvent is present). Here, the reaction solvent means an organic solvent (e.g., toluene). It is preferable to carry out the above reaction of isothiouronium salt (1) in the absence of a reaction solvent. 【0104】 -At least one selected from the group consisting of alkali metal sulfites and alkaline earth metal sulfites- In the step of preparing the raw material composition, isothiouronium salt (1) may be reacted with sulfur-containing compound (2), at least one selected from the group consisting of basic compound (3), basic compound (X), and ammonia, and other basic compounds. From the viewpoint of obtaining the effects of the method for producing thiol compounds of this disclosure more effectively, it is preferable in the reaction step to react isothiouronium salt (1) with at least one selected from the group consisting of sulfur-containing compound (2), basic compound (3), basic compound (X), and ammonia, and at least one selected from the group consisting of alkali metal sulfites and alkaline earth metal sulfites (hereinafter, these are collectively referred to as "specific sulfites"). 【0105】 The amount of specific sulfite added is preferably 0.1 mol% to 10 mol%, and more preferably 1 mol% to 8 mol%, relative to the amount of isothiouronium salt (1). 【0106】 Specific sulfites may be added to the NaSH aqueous solution beforehand. 【0107】The following timings are preferred for adding the specific sulfite. For example, in the case of Method 1 described above, it is preferable to charge the reactor with an isothiuronium salt reaction mass (hereinafter also referred to as "ITU salt mass"), then dropwise add the sulfur-containing compound (2) and the base, and then add the specific sulfite (see Example 1 described below). In the case of Method 2 described above, the reactor is charged with the sulfur-containing compound (2), the base, and the specific sulfite, and then dropwise add the ITU salt mass (see Example 2 described below). 【0108】 -Preferred pH- The reaction of isothiuronium salt (1) is preferably carried out under conditions of pH 7 or higher (preferably pH 7 to pH 14). 【0109】 In this disclosure, pH refers to the pH at 25°C unless otherwise specified. 【0110】 -Preferred reaction temperature- The reaction of isothiouronium salt (1) is preferably carried out under conditions of 30°C to 80°C (more preferably 40°C to 70°C). 【0111】 -Preferred reaction time- The reaction of isothiouronium salt (1) is preferably carried out for 0.3 hours to 10 hours (preferably 1 hour to 5 hours). 【0112】 - Separation of reaction mixture and target product - In the step of preparing the raw material composition, an isothiouronium salt (1) may be reacted with a sulfur-containing compound (2) and at least one selected from the group consisting of a basic compound (3), a basic compound (X), and ammonia to obtain a reaction mixture containing a polythiol component (A), a thioamide component (B), and a thiourea compound (4) described later. The reaction mixture may contain components other than those mentioned above (e.g., unreacted raw materials, reaction by-products, etc.). 【0113】As a method for separating the raw material composition (i.e., the composition containing the polythiol component (A) and the thioamide component (B)) from the reaction mixture, known methods can be appropriately applied. For example, the reaction mixture can be allowed to stand, and the mixture can be separated into an organic layer containing the raw material composition containing the polythiol component (A) and the thioamide component (B) and an aqueous layer containing the thiourea compound (4), and the raw material composition can be separated from the resulting organic layer. As a method for separating the raw material composition from the organic layer, conventional methods such as acid washing, water washing, distillation, and filtration can be appropriately combined and applied. 【0114】 When separating the thiourea compound (4) from the aqueous layer described above, there are no particular restrictions on the separation method, and conventional methods can be appropriately combined and applied. 【0115】 - Compound (Px), Thiourea compound (4) - The steps for preparing the raw material composition may include: reacting a compound (Px) represented by the following formula (Px) with a thiourea compound (4) represented by the following formula (4) to produce an isothiouronium salt (1); and reacting the isothiouronium salt (1) in the presence of a sulfur-containing compound (2) to obtain the raw material composition. 【0116】 【0117】 In formula (Px), R Ｘ represents an organic group with 1 to 30 carbon atoms and an (m+n) valency, where n is an integer from 1 to 8, m is an integer from 0 to 8, and A represents a hydroxyl group or a halogen atom. If there are multiple A's in formula (Px), the multiple A's may be the same or different. In formula (4), R ２ , R ３ , and R ４ Each of these independently represents either a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms. 【0118】 In formula (Px), R Ｘ n and m are, respectively, R in equation (A). １ , n, and m are synonymous, and the same applies to preferred embodiments. However, R in formula (Px) Ｘ And, R in equation (A) １ And may be the same or different. 【0119】 In formula (Px), A represents a hydroxyl group or a halogen atom. If there are multiple A's in formula (Px), the multiple A's may be the same or different. 【0120】 In the process of producing the isothiouronium salt (1), two or more compounds (Px) may be reacted with the thiourea compound (4). 【0121】 In formula (4), R ２ , R ３ , and R ４ Each of these independently represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms. In formula (4), R ２ , R ３ , and R ４ These are, respectively, R in equation (1). ２ , R ３ , and R ４ This is synonymous with the same as the preferred configuration. 【0122】 In this disclosure, "thiourea compound" means thiourea (i.e., in formula (4), R ２ , R ３ , and R ４ However, all of them are compounds in which hydrogen atoms exist) and their derivatives (i.e., in formula (4), R ２ , R ３ , and R ４ This refers to a compound in which at least one of the elements is a monovalent organic group having 1 to 10 carbon atoms. 【0123】 When producing the isothiouronium salt (1), only one type of thiourea compound (4) may be obtained, or two or more types may be obtained. 【0124】 Thiourea compound (4) is a raw material for isothiouronium salt (1). On the other hand, as mentioned above, thioourea compound (4) can be obtained by reaction in the presence of sulfur-containing compound (2) of isothiouronium salt (1). If thioourea compound (4) is obtained by reaction in the presence of sulfur-containing compound (2) of isothiouronium salt (1), recycling of thioourea compound (4) can be realized. 【0125】(Step to obtain the polythiol composition) The step to obtain the polythiol composition in manufacturing method X is to react the raw material composition in the presence of a basic compound (i.e., to base treatment) to obtain the polythiol composition of the present disclosure described above (i.e., a polythiol composition containing a polythiol component (A) and a thioamide component (B), wherein the peak area ratio [thioamide component (B) / polythiol component (A)] is 3 area % or less). 【0126】 The basic compound used in the process of obtaining the polythiol composition preferably contains at least one amine compound. Hereinafter, the amine compound that may be included in the basic compound used in the process of obtaining the polythiol composition will be referred to as "amine compound A". Amine compound A may consist of only one type or two or more types. 【0127】 - Amine compound A - Amine compound A preferably has a pKa in the range of 4 to 12, and more preferably has a pKa in the range of 5 to 11. 【0128】 Furthermore, amine compound A has a primary amino group (i.e., -NH ２ Preferably, the amine compound A contains at least one of a tertiary amino group (i.e., a -NH- group) and a secondary amino group (i.e., a -NH- group). In this case, the amine compound A may further contain a tertiary amino group (i.e., a -NR ２ It may contain a group (R is an organic group). 【0129】 Amine compound A may be a compound that satisfies only one of the following conditions: having a pKa in the range of 4 to 12, and containing at least one of a primary amino group and a secondary amino group, or it may be a compound that satisfies both conditions. The basic compound used in the process of obtaining the polythiol composition may include amine compound A that satisfies both of the above conditions. Furthermore, the basic compound used in the process of obtaining the polythiol composition may include both amine compound A having a pKa in the range of 4 to 12 and amine compound A containing at least one of a primary amino group and a secondary amino group, or it may include only one of them. 【0130】Amine compound A may be a chain-like amine compound or a cyclic amine compound (for example, morpholine, piperidine, piperazine, etc.). 【0131】 The molecular weight of amine compound A is preferably 1000 or less, more preferably 500 or less, even more preferably 300 or less, and even more preferably 200 or less. The lower limit of the molecular weight of amine compound A is, for example, 45 or more, preferably 59 or more, and more preferably 60 or more. 【0132】 Amine compound A may be an amine compound containing monoalkylamino groups, wherein the total number of monoalkylamino groups is 1 to 6 (preferably 1 to 3, more preferably 1 or 2, and even more preferably 1). 【0133】 An example of amine compound A is an amine compound containing a monoalkylamino group, with a total number of monoalkylamino groups of 1 and a molecular weight of 300 or less. 【0134】 Examples of amine compound A include, for example, dialkylamines having 2 to 10 carbon atoms (e.g., dimethylamine, diethylamine, di-n-propylamine, di-n-butylamine, etc.), alkyltriamines having 2 to 10 carbon atoms (e.g., bis(2-aminoethyl)amine, etc.), bis(hydroxyalkyl)amines having 2 to 10 carbon atoms (e.g., bis(hydroxyethyl)amine, etc.), cyclic amines having 2 to 10 carbon atoms (e.g., morpholine, piperidine, piperazine), and alkyl(hydroxyalkyl)amines having 2 to 10 carbon atoms (e.g., N-methylethanolamine (NMEA), N-ethylethanolamine, N-n-propylethanolamine, N-isopropylethanolamine, etc.). 【0135】Furthermore, amine compound A may be at least one selected from the group consisting of, for example, benzylamine, ethylenediamine, monoethanolamine, n-butylamine, m-xylylenediamine, di-n-butylamine, dipropylamine, morpholine, piperidine, N-(2-aminoethyl)piperazine, 1-methylpiperazine, diethylenetriamine, and N,N'-dimethylethylenediamine. 【0136】 Amine compound A may contain a hydroxyl group. Examples of amine compound A containing a hydroxyl group include alkyl (hydroxyalkyl)amines having 2 to 10 carbon atoms (for example, N-methylethanolamine). 【0137】 - Amount of basic compound to be added - The mass ratio of the basic compound (e.g., amine compound A) to the raw material composition (i.e., mass ratio [amine compound A / raw material composition]) can be adjusted as appropriate, but is preferably 0.01 to 1.0, preferably 0.02 to 0.5, and preferably 0.05 to 0.3. 【0138】 The temperature of the base treatment (i.e., the reaction of the raw material composition in the presence of a basic compound) is preferably 40°C to 80°C, more preferably 50°C to 80°C, and even more preferably 50°C to 75°C. 【0139】 The duration of the base treatment (i.e., the reaction of the raw material composition in the presence of a basic compound) is preferably 0.1 to 10 hours, more preferably 0.2 to 5 hours, and even more preferably 0.2 to 4 hours. 【0140】 The base treatment may be carried out in the presence of the reaction solvent or in the absence of the reaction solvent (i.e., under conditions where the reaction solvent is not present). Here, the reaction solvent refers to an organic solvent (e.g., toluene, xylene, chlorobenzene, dichlorobenzene, etc.). It is preferable to carry out the base treatment in the absence of the reaction solvent. 【0141】 [Polymerizable Composition] The polymerizable composition of this disclosure comprises the polythiol composition of this disclosure and a polyiso(thio)cyanate compound. 【0142】<Polyiso(thio)cyanate compounds> The polyiso(thio)cyanate compounds are not particularly limited as long as they can exhibit the effects of the present disclosure, and conventionally known compounds can be used. The compounds are not particularly limited as long as they have at least two or more iso(thio)cyanate groups in one molecule, and specifically, for example, aliphatic polyisocyanate compounds such as tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, octamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate methyl ester, lysine triisocyanate, xylylene diisocyanate, etc. Alicyclic polyisocyanate compounds such as isophorone diisocyanate, bis(isocyanatomethyl)cyclohexane, bis(isocyanatocyclohexyl)methane, dicyclohexyldimethylmethane diisocyanate, 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 3,8-bis(isocyanatomethyl)tricyclodecane, 3,9-bis(isocyanatomethyl)tricyclodecane, 4,8-bis(isocyanatomethyl)tricyclodecane, and 4,9-bis(isocyanatomethyl)tricyclodecane; aromatic polyisocyanate compounds such as tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, diphenyl sulfide-4,4-diisocyanate, and phenylene diisocyanate; Heterocyclic polyisocyanate compounds such as 2,5-diisocyanatothiophene, 2,5-bis(isocyanatomethyl)thiophene, 2,5-diisocyanatotetrahydrothiophene, 2,5-bis(isocyanatomethyl)tetrahydrothiophene, 3,4-bis(isocyanatomethyl)tetrahydrothiophene, 2,5-diisocyanato-1,4-dithiane, 2,5-bis(isocyanatomethyl)-1,4-dithiane, 4,5-diisocyanato-1,3-dithiolane, and 4,5-bis(isocyanatomethyl)-1,3-dithiolane;Aliphatic polyisothiocyanate compounds such as hexamethylene diisothiocyanate, lysine diisothiocyanate methyl ester, lysine triisothiocyanate, and xylylene diisothiocyanate; Alicyclic polyisothiocyanate compounds such as isophorone diisothiocyanate, bis(isothiocyanatomethyl)cyclohexane, bis(isothiocyanatocyclohexyl)methane, cyclohexane diisothiocyanate, methylcyclohexane diisothiocyanate, 2,5-bis(isothiocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isothiocyanatomethyl)bicyclo-[2.2.1]-heptane, 3,8-bis(isothiocyanatomethyl)tricyclodecane, 3,9-bis(isothiocyanatomethyl)tricyclodecane, 4,8-bis(isothiocyanatomethyl)tricyclodecane, and 4,9-bis(isothiocyanatomethyl)tricyclodecane; Examples include aromatic polyisothiocyanate compounds such as tolylene diisothiocyanate, 4,4-diphenylmethane diisothiocyanate, and diphenyl disulfide-4,4-diisothiocyanate; and sulfur-containing heterocyclic polyisothiocyanate compounds such as 2,5-diisothiocyanatothiophene, 2,5-bis(isothiocyanatomethyl)thiophene, 2,5-isothiocyanatotetrahydrothiophene, 2,5-bis(isothiocyanatomethyl)tetrahydrothiophene, 3,4-bis(isothiocyanatomethyl)tetrahydrothiophene, 2,5-diisothiocyanato-1,4-dithiane, 2,5-bis(isothiocyanatomethyl)-1,4-dithiane, 4,5-diisothiocyanato-1,3-dithiolane, and 4,5-bis(isothiocyanatomethyl)-1,3-dithiolane. The polyiso(thio)cyanate compound may include at least one selected from these. 【0143】 Furthermore, as polyiso(thio)cyanate compounds, halogen-substituted compounds such as chlorine-substituted and bromine-substituted compounds, alkyl-substituted compounds, alkoxy-substituted compounds, nitro-substituted compounds, prepolymer-type modified compounds with polyhydric alcohols, carbodiimide-substituted compounds, urea-substituted compounds, biuret-substituted compounds, and dimerization or trimmerization reaction products can also be used. 【0144】The polyiso(thio)cyanate compound is preferably a polyisocyanate compound, and preferably contains at least one selected from the group consisting of pentamethylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, bis(isocyanatomethyl)cyclohexane, bis(isocyanatocyclohexyl)methane, 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and phenylene diisocyanate. 【0145】 The mixing ratio of the polythiol composition and the polyiso(thio)cyanate compound is not particularly limited. For example, the molar ratio (mercapto group / iso(thio)cyanate group) of the mercapto group of the polythiol compound contained in the polythiol composition to the iso(thio)cyanate group of the polyiso(thio)cyanate compound is preferably 0.5 to 3.0, more preferably 0.6 to 2.0, and even more preferably 0.8 to 1.3. When the mixing ratio is within the above range, it tends to be possible to satisfy various properties such as refractive index and heat resistance required for plastic lenses, etc., in a well-balanced manner. 【0146】 The polymerizable composition of this disclosure may include a polyiso(thio)cyanate composition containing the above-mentioned polyiso(thio)cyanate compound. 【0147】 Here, a polyisocyanate composition means a composition containing at least one polyisocyanate compound. 【0148】 The polyisocyanate composition may contain components other than the polyisocyanate compound as impurities. Preferably, the polyisocyanate composition contains at least one polyisocyanate compound as a main component. In this disclosure, "main component" in the polyisocyanate composition means the component that has the largest peak in gas chromatography measurement. 【0149】The polyisocyanate composition preferably contains xylylene diisocyanate (XDI). 【0150】 Hereinafter, a polyisocyanate composition containing xylylene diisocyanate will also be referred to as an XDI composition. It is preferable that the XDI composition contains xylylene diisocyanate as its main component. 【0151】 The XDI composition preferably contains at least one compound selected from the group consisting of the following compounds (N1), (N2), and (N3). 【0152】 【0153】 The following describes preferred embodiments of the XDI composition from the viewpoint of superior stability of the polyiso(thio)cyanate composition and transparency of the resin formed using the polyiso(thio)cyanate composition. 【0154】 If the XDI composition contains compound (N1), it is preferable that the peak area of ​​compound (N1) in gas chromatography measurement under the following GC condition 1 is 0.20 ppm or more relative to the peak area of ​​xylylene diisocyanate (1). -GC condition 1- Packing material: DB-1 (film thickness) 1.5 μm Column: Inner diameter 0.53 mm × length 60 m (manufactured by Agilent) Oven temperature: Heating from 130°C to 220°C at 3°C / min, then heating to 300°C at 10°C / min after reaching 220°C. Split ratio: Pulsed splitless method Inlet temperature: 280°C Detector temperature: 300°C Carrier gas: N ２ 158 kPa, H ２ Pressure: 55 kPa, Air pressure: 45 kPa (constant pressure control) Solvent: Chloroform Sample concentration: 2.0% by mass chloroform solution Injection volume: 2 μL Detection method: FID 【0155】The peak area of ​​compound (N1) is more preferably 5.0 ppm or more, even more preferably 50 ppm or more, and even more preferably 100 ppm or more, relative to the peak area 1 of xylylene diisocyanate. The peak area of ​​compound (N1) is more preferably 4000 ppm or less, more preferably 3000 ppm or less, even more preferably 2000 ppm or less, even more preferably 1500 ppm or less, and even more preferably 1000 ppm or less, relative to the peak area 1 of xylylene diisocyanate. The peak area of ​​compound (N1) can be measured in accordance with the method described in paragraph 0377 of Japanese Patent No. 6373536. 【0156】 If the XDI composition contains compound (N2), it is preferable that the peak area of ​​compound (N2) in gas chromatography measurement under the following GC condition 2 is 0.05 ppm or more relative to the peak area of ​​xylylene diisocyanate. -GC condition 2- Column: HP-50+, inner diameter 0.25 mm × length 30 m × film thickness 0.25 μm (Hewlett-Packard) Oven temperature: Heat from 50°C to 280°C at a rate of 10°C / min, hold for 6 min after reaching 280°C. Split ratio: Pulsed splitless method Inlet temperature: 200°C Detector temperature: 280°C Carrier gas: He Carrier gas flow rate: 1.0 ml / min (constant flow rate control) Sample concentration: 1.0 mass% dichloromethane solution Injection volume: 1.0 μL Detection method: SIM (monitoring ions: m / z 180, 215) (percentage of xylylene diisocyanate (XDI) content) 【0157】The peak area of ​​the above compound (N2) is more preferably 0.1 ppm or more, even more preferably 0.3 ppm or more, and still more preferably 0.6 ppm or more, relative to the peak area 1 of xylylene diisocyanate. The peak area of ​​the above compound (N2) is more preferably 200 ppm or less, more preferably 150 ppm or less, even more preferably 100 ppm or less, even more preferably 80 ppm or less, even more preferably 70 ppm or less, and still more preferably 60 ppm or less, relative to the peak area 1 of xylylene diisocyanate. The peak area of ​​the above compound (N2) can be measured in accordance with the method described in paragraphs 0375 and 0376 of Japanese Patent No. 6373536. 【0158】 When the XDI composition contains compound (N3), it is preferable that the peak area of ​​compound (N3) in the gas chromatography measurement under the aforementioned GC condition 1 is 0.10 ppm or more relative to the peak area 1 of xylylene diisocyanate. The peak area of ​​compound (N3) is more preferably 0.1 ppm or more, even more preferably 3.0 ppm or more, and even more preferably 5.0 ppm or more, relative to the peak area 1 of xylylene diisocyanate. The peak area of ​​compound (N3) is preferably 1000 ppm or less, more preferably 500 ppm or less, even more preferably 300 ppm or less, even more preferably 100 ppm or less, and even more preferably 75 ppm or less, relative to the peak area 1 of xylylene diisocyanate. The peak area of ​​compound (N3) can be measured in accordance with the method described in paragraph 0377 of Japanese Patent No. 6373536. 【0159】 The acidity of the XDI composition is preferably 3000 ppm or less, more preferably 2000 ppm or less, even more preferably 1000 ppm or less, even more preferably 100 ppm or less, even more preferably 50 ppm or less, even more preferably 30 ppm or less, and even more preferably less than 15 ppm. The lower limit of the acidity of the XDI composition is not particularly limited, but the lower limit is, for example, 1 ppm. The acidity of the XDI composition can be measured in accordance with the method described in paragraph 0091 of International Publication No. 2021 / 256417. The XDI composition may also contain stabilizers. 【0160】 <Thiol Compound XS> The polymerizable composition of this disclosure may further contain thiol compound XS, which is a thiol compound other than polythiol component (A) contained in the polythiol composition described above. 【0161】 The thiol compound XS is preferably methanedithiol, 1,2-ethanedithiol, 1,2,3-propanetrithiol, pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), tetrakis(mercaptomethylthiomethyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, or bis(2-mercaptoethyl)sulf It is at least one selected from the group consisting of iodide, bis(2,3-dimercaptopropyl) sulfide, 2,5-dimercaptomethyl-1,4-dithiane, 2,5-dimercapto-1,4-dithiane, 2,5-dimercaptomethyl-2,5-dimethyl-1,4-dithiane, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, and 4,6-bis(mercaptomethylthio)-1,3-dithiane. 【0162】 The polymerizable compositions of this disclosure may contain other components besides polythiol compounds and polyiso(thio)cyanate compounds for the purpose of improving the various physical properties of the resin, handling properties, polymerization reactivity of the polymerizable composition, etc. Examples of other components include polymerization catalysts, internal release agents, resin modifiers, chain extenders, crosslinking agents, radical scavengers, light stabilizers, ultraviolet absorbers, antioxidants, oil-soluble dyes, fillers, adhesion improvers, antibacterial agents, antistatic agents, dyes, fluorescent whitening agents, fluorescent pigments, inorganic pigments, and other blue ink agents. 【0163】 Examples of polymerization catalysts include tertiary amine compounds, their inorganic or organic salts, metal compounds, quaternary ammonium salts, and organic sulfonic acids. 【0164】As an internal release agent, an acidic phosphate ester can be used. Examples of acidic phosphate esters include phosphate monoesters and phosphate diesters, which can be used individually or in combination of two or more types. 【0165】 Examples of resin modifiers include episulfide compounds, alcohol compounds, amine compounds, epoxy compounds, organic acids and their anhydrides, and olefin compounds including (meth)acrylate compounds. The polymerizable composition of this disclosure can be obtained by mixing the above components. 【0166】 [Resin, Molded Article] The resin of this disclosure includes a cured product of the polymerizable composition of this disclosure. The molded article of this disclosure includes the resin of this disclosure. The method for producing the molded article of this disclosure is not particularly limited, but a preferred method is casting polymerization. First, the polymerizable composition is injected between molds held together by a gasket or tape. At this time, depending on the physical properties required of the resulting plastic lens, it is often preferable to perform degassing treatment under reduced pressure, filtration treatment under pressure or reduced pressure, etc., as necessary. 【0167】 Polymerization conditions are not limited to specific conditions, as they vary greatly depending on the composition of the polymerizable composition, the type and amount of catalyst used, the shape of the mold, etc. For example, polymerization is carried out at a temperature of -50°C to 150°C for 1 to 50 hours. In some cases, it is preferable to maintain the temperature in the range of 10°C to 150°C or gradually raise the temperature and cure it for 1 to 48 hours. 【0168】 The molded article may be subjected to treatments such as annealing as needed. Annealing is usually carried out at a temperature between 50°C and 150°C, preferably between 90°C and 140°C, and more preferably between 100°C and 130°C. 【0169】 <Applications> The resin obtained from the polymerizable composition of this disclosure can be used as a material for manufacturing molded articles of various shapes by changing the type of mold used during casting polymerization. 【0170】[Optical Materials] The optical materials of this disclosure include the resin of this disclosure. Molded articles obtained from the polymerizable composition of this disclosure can be made of a material with reduced yellowness without impairing transparency. Furthermore, molded articles obtained from a polymerizable composition containing the polythiol composition of the first embodiment can be made of a material that also possesses excellent devitrification. Therefore, it can be used in various optical materials such as plastic lenses. 【0171】 [Lenses] The lenses of this disclosure include the resin of this disclosure. Lenses are particularly preferred as optical materials. Examples of lenses include plastic spectacle lenses and plastic polarizing lenses. 【0172】 <Plastic Eyeglass Lenses> Plastic eyeglass lenses using a lens substrate made from the molded product of the present disclosure may have a coating layer applied to one or both sides as needed. The plastic eyeglass lenses of the present disclosure comprise a lens substrate containing a cured product of the polymerizable composition described above, and a coating layer. 【0173】 Examples of coating layers include primer layers, hard coat layers, anti-reflective layers, anti-fogging layers, anti-stain layers, and water-repellent layers. These coating layers can be used individually or in multiple layers. When applying coating layers to both surfaces, the same coating layer may be applied to each surface, or different coating layers may be applied to each surface. 【0174】 These coating layers may each contain known additives such as infrared absorbers to protect the eyes from infrared rays, light stabilizers and antioxidants to improve the weather resistance of the lenses, photochromic compounds, dyes, and pigments to enhance the fashionability of the lenses, and antistatic agents to improve the performance of the lenses. For layers coated by application, various leveling agents may be used to improve the applicability. In addition, an anti-fog layer, an anti-stain layer, and a water-repellent layer may be formed on top of the anti-reflective layer as needed. 【0175】The embodiments described above are examples of this disclosure, and various other configurations can be adopted as long as they do not impair the effects of this disclosure. 【0176】 Examples of the present disclosure are shown below, but the present disclosure is not limited to these examples.Hereinafter, unless otherwise specified, "%" and "ppm" mean "mass%" and "mass ppm," and pH means pH at 25°C. 【0177】 [HPLC Analysis Conditions] The HPLC (High-Performance Liquid Chromatography) analysis conditions in this example are as follows: 【0178】 -HPLC Analysis Conditions- • Machine: Shimadzu HPLC Detector: SPD-10Avp Pump: LC-10ADvp Thermostat: CTO-10Avp • Column: Mightysil RP-18 Aqua 250-4.6 (5μm) • Mobile Phase: 0.1mol-KH ２ PO ４ A liquid obtained by adjusting the pH of an aqueous solution to 3 with phosphoric acid. • Flow rate: 0.9 mL / min • Temperature bath: 40°C • Detector: UV 220 nm 【0179】 [Production Example 1] <Production of Isothiouronium Salt (1-1)> As Production Example 1, isothiouronium salt (1-1) was produced as isothiouronium salt (1). Details are shown below. 184.4 parts by mass of 2-mercaptoethanol and 29.4 parts by mass of degassed water (dissolved oxygen concentration 2 ppm) were charged into the reactor. Then, 158.6 parts by mass of a 30.5% by mass aqueous sodium hydroxide solution was added dropwise over 30 minutes at 12°C to 35°C, followed by the dropwise addition of 110.8 parts by mass of epichlorohydrin over 3 hours at 29°C to 36°C, and the mixture was stirred for 1 hour. This yielded an aqueous solution containing compound (Px-1) as compound (Px). 【0180】 The structure of compound (Px-1) is as follows. The formation of compound (Px-1) was confirmed by NMR. 【0181】 【0182】 Next, 498.7 parts by mass of 35% hydrochloric acid were added to a reactor containing an aqueous solution of the above compound (Px-1), and then 275.3 parts by mass of thiourea as the thiourea compound (4) with a purity of 99.30% was added. The reaction was carried out by stirring at 110°C under reflux for 3 hours to perform the isothiouronium chloride reaction. This yielded an aqueous solution of isothiouronium salt (1-1) as isothiouronium salt (1). 【0183】 The structure of isothiuronium salt (1-1) is as follows. The formation of isothiuronium salt (1-1) was confirmed by NMR. 【0184】 【0185】[Examples 1-8, Comparative Examples 1-2] <<Preparation of Raw Material Composition 1>> An aqueous solution of isothiouronium salt (1-1) obtained in Production Example 1 (1158.6 g) and toluene (448.3 g) were charged into a reactor. To this, 84.9 parts by mass of 31.1% by mass sodium hydroxide aqueous solution, 74.0 parts by mass of 25.30% by mass ammonia aqueous solution, and 385.4 parts by mass of 48.0% by mass sodium hydrogen sulfide aqueous solution were added (all of the above, addition method (1)). The resulting liquid was stirred at 54°C to 62°C for 3 hours to carry out the reaction, and then allowed to stand to separate into an aqueous layer and an organic layer. HPLC analysis confirmed that thiourea was present in the aqueous layer. The above organic layer was acid-washed with 227 parts by mass of 35% hydrochloric acid water at 35°C to 43°C for 2 hours, then washed with 227 parts by mass of degassed water (dissolved oxygen concentration 2 ppm) at 35°C to 45°C for 15 minutes, then washed with 227 parts by mass of 0.1% ammonia water for 15 minutes, and then washed twice with 227 parts by mass of degassed water (dissolved oxygen concentration 2 ppm) at 35°C to 45°C for 15 minutes each. From the organic layer after the above washing, the solvent was removed by distillation under reduced heating pressure, then trace amounts of water were removed under reduced heating pressure, and then vacuum filtration was performed using a 3 μm PTFE type membrane filter to obtain raw material composition 1 mainly composed of the aforementioned polythiol A1 (i.e., 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane; structure shown below). Here, the main component in a composition containing a polythiol compound refers to the component with the largest peak area in HPLC analysis. HPLC analysis confirmed that raw material composition 1 also contains thioamide B1 (structure shown below) as thioamide component (B) in a proportion such that the peak area ratio [thioamide component (B) / polythiol component (A)] in HPLC analysis is 8.3 area. Here, in thioamide B1, one or two of the three X groups are -S-C(=S)-NH ２ It is a group, and the rest is a mercapto group (-SH group). 【0186】 【0187】Furthermore, sodium hydrogen sulfide (NaSH) is an example of a sulfur-containing compound (2) (specifically, in formula (2), M １ (where is a sodium atom, and m, k, and n are all 1 in a sulfur-containing compound), and sodium hydroxide (NaOH) is an example of a basic compound (3) (specifically, in formula (3), M ２ It is a basic compound in which the atom is sodium and both p and q are 1. 【0188】 <<Preparation of Raw Material Composition 2>> An aqueous solution (1158.6 g) of the isothiouronium salt (1-1) obtained in Production Example 1 and toluene (448.3 g) were charged into a reactor, and 334.5 parts by mass of 25.2% by mass aqueous ammonia were added thereto. The resulting liquid was stirred at 54°C to 62°C for 3 hours to carry out the reaction, and then allowed to stand to separate into an aqueous layer and an organic layer. HPLC analysis confirmed that the aqueous layer did not contain thiourea. The same procedure as the procedure for the organic layer in Raw Material Composition 1 was performed on the organic layer to obtain Raw Material Composition 2, which mainly consists of polythiol A1. HPLC analysis further confirmed that the raw material composition did not contain thioamide component (B). 【0189】 <<Preparation of Polythiol Composition>> Raw material composition 1 and raw material composition 2 were mixed in a ratio such that the peak area ratio [thioamide component (B) / polythiol component (A)] determined by HPLC analysis was area % as shown in Table 1, to obtain a polythiol composition. However, in Comparative Example 2, raw material composition 2 was not used, and raw material composition 1 itself was used as the polythiol composition. 【0190】<<Preparation of Polymerizable Composition>> XDI composition X1 (52 parts by mass), which is one embodiment of the polyiso(thio)cyanate composition as described above, dibutyltin dichloride (0.015 parts by mass) as a curing catalyst, Zerec UN (product of Stepan, trade name; acidic phosphate ester) (0.10 parts by mass) as a release agent, and Biosorb 583 (manufactured by Kyodo Yakuhin Co., Ltd.; ultraviolet absorber) (1.5 parts by mass) as an ultraviolet absorber were mixed and dissolved at 20°C. The polythiol composition obtained above (48 parts by mass) was then added and mixed to obtain a polymerizable composition as a homogeneous liquid. 【0191】 In XDI composition X1, gas chromatography measurements were performed under GC condition 1 and GC condition 2 as described above. The results showed that the peak area of ​​compound (N1) was 0.20 ppm or more (specifically 600 ppm) relative to the peak area 1 of xylylene diisocyanate, the peak area of ​​compound (N2) was 0.05 ppm or more (specifically 18 ppm) relative to the peak area 1 of xylylene diisocyanate, and the peak area of ​​compound (N3) was 0.10 ppm or more (specifically 100 ppm) relative to the peak area 1 of xylylene diisocyanate. 【0192】<<Manufacturing of Resin Molded Articles>> The polymerizable composition described above was degassed at 600 Pa for 1 hour. The degassed polymerizable composition was filtered through a 1 μm Teflon® filter, and the filtrate was injected between a pair of glass molds fixed with tape. The pair of glass molds was then placed in an oven, and the oven temperature was set to 10°C. Next, the oven temperature was raised from 10°C to 120°C over 38 hours. Through this process, the monomers (polyisocyanate compounds and polythiol compounds) in the polymerizable composition were polymerized, and a molded article containing resin (i.e., a cured product of the polymerizable composition) was formed between the pair of glass molds. Subsequently, the oven was cooled, and after cooling, the pair of glass molds were removed from the oven, and then the molded article containing resin (hereinafter referred to as the resin molded article) was removed from the pair of glass molds. A flat resin molded article (i.e., a lens) with a thickness of 9 mm was obtained. The obtained resin molded article was annealed at 120°C for 1 hour. 【0193】 ≪Evaluation of Yellowness Index (YI) of Resin Molded Products≫ The yellowness index (YI) of the resin molded products after annealing was measured using a Konica Minolta CM-5 spectrophotometer. The lower the yellowness index (YI) of the resin molded product, the better the hue of the resin molded product. The results are shown in Table 1. 【0194】 【0195】 As shown in Table 1, in Examples 1 to 8, which used polythiol compositions with a peak area ratio [thioamide component (B) / polythiol component (A)] of 3 area % or less, the yellowness (YI (Yellow Index)) of the resulting resin molded articles was reduced compared to Comparative Examples 1 and 2, which used polythiol compositions with a peak area ratio [thioamide component (B) / polythiol composition] of more than 3 area %. 【0196】[Example 101] <<Production of Polythiol Composition (Base Treatment)>> Monoethanolamine (MEA) (3.20 parts by mass) as a base (i.e., a basic compound) was added to the aforementioned raw material composition 1 (i.e., the polythiol composition of Comparative Example 2) (50 parts by mass), and the resulting mixture was stirred at 60°C for 2 hours to perform base treatment of raw material composition 1. After stirring (i.e., after base treatment), water (50 parts by mass) was added to the liquid, stirred, and then allowed to stand to separate into an aqueous layer and an organic layer. The obtained organic layer was washed twice with deaerated water (dissolved oxygen concentration 2 ppm) (50 parts by mass) at 35°C to 45°C for 15 minutes each time. After removing trace amounts of water from the organic layer under reduced heating pressure, a polythiol composition was obtained by vacuum filtration using a 3 μm PTFE type membrane filter, with a peak area ratio [thioamide component (B) / polythiol component (A)] of the values ​​shown in Table 2. 【0197】 Using the obtained polythiol composition, polymerizable compositions, resin molded articles, and the yellowness of the resin molded articles were manufactured in the same manner as in Example 1. The results are shown in Table 2. 【0198】 [Example 102] The same procedure as in Example 101 was followed, except that 3.20 parts by mass of MEA was replaced with 5.30 parts by mass of dipropylamine (DPA) and the processing time (stirring time) was changed to 0.5 hours. The results are shown in Table 2. 【0199】 Table 2 shows, for comparison, the YI values ​​of the resin molded articles of Comparative Example 2, described above, in which raw material composition 1 itself was used as the polythiol composition (i.e., without base treatment). 【0200】 【0201】As shown in Table 2, in Examples 101 and 102, the peak area ratio [thioamide component (B) / polythiol component (A)] in the raw material composition 1 was reduced by base treatment, and as a result, a polythiol composition with a peak area ratio [thioamide component (B) / polythiol component (A)] of 3 area % or less was obtained. In Examples 101 and 102, a resin molded article with reduced yellowness (YI) was produced using the obtained polythiol composition. 【0202】 [Production Example 2] <Production of Isothioronium Salt (1-2)> As Production Example 2, isothioronium salt (1-2) was produced as isothioronium salt (1). Details are shown below. 89.25 parts by mass of 2-mercaptoethanol, 44.61 parts by mass of degassed water (dissolved oxygen concentration 2 ppm), and 0.58 parts by mass of a 31% by mass sodium hydroxide aqueous solution were charged into the reactor. Next, 107.68 parts by mass of epichlorohydrin were added dropwise over 4.5 hours at 9°C to 11°C, and the mixture was stirred for 1 hour. The formation of 1-chloro-3-(2-hydroxyethylthio)-2-propanol was confirmed from NMR data. Next, 262.30 parts by mass of a 17.3% by mass sodium sulfide aqueous solution were added dropwise over 1 hour at 7°C to 37°C, and the mixture was stirred for 3 hours. This yielded an aqueous solution containing compound (Px-2) as compound (Px). 【0203】 The structure of compound (Px-2) is as follows. The formation of compound (Px-2) was confirmed by NMR. 【0204】 【0205】 Next, 484.6 parts by mass of 35% hydrochloric acid were added to a reactor containing an aqueous solution of the above compound (Px-2). Then, 214 parts by mass of thiourea as the thiourea compound (4) with a purity of 99.90% was added, and the mixture was stirred at 110°C under reflux for 3 hours to carry out the isothiouronium chloride reaction. This yielded an aqueous solution of isothiouronium salt (1-2) as isothiouronium salt (1). 【0206】The isothiuronium salt (1-2) is at least one compound selected from the group consisting of the following three compounds. The formation of the isothiuronium salt (1-2) was confirmed by NMR. 【0207】 【0208】 [Comparative Example 201] An aqueous solution of isothiuronium salt (1-2) obtained in Production Example 2 (1203.0 g) and toluene (373 g) were charged into a reactor, and 191.2 parts by mass of 25.4% by mass sodium hydroxide aqueous solution and 271.7 parts by mass of 48.0% by mass sodium hydrogen sulfide aqueous solution were added thereto (addition method (1)). The resulting liquid was stirred at 54°C to 62°C for 1 hour to carry out the reaction, and then allowed to stand to separate into an aqueous layer and an organic layer. 【0209】 HPLC analysis confirmed the presence of thiourea in the aqueous layer. 【0210】The above organic layer was subjected to two acid washes with 125 parts by mass of 35% hydrochloric acid solution at 35°C to 43°C for 30 minutes each, followed by five washes with 125 parts by mass of degassed water (dissolved oxygen concentration 2 ppm) at 35°C to 45°C for 15 minutes each. From the organic layer after washing as described above, the solvent was removed by distillation under reduced heating pressure, and then trace amounts of water were removed under reduced heating pressure. Finally, vacuum filtration was performed using a 3 μm PTFE type membrane filter to obtain a raw material composition 201 (i.e., the polythiol composition of Comparative Example 201) mainly composed of the aforementioned polythiol A2 (i.e., at least one selected from the group consisting of 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (compound (A2-1) below), 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (compound (A2-2) below), and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (compound (A2-3) below)). Here, the main component in a composition containing a polythiol compound means the component with the largest peak area in HPLC analysis. HPLC analysis confirmed that the raw material composition 201 also contains thioamide B2 as thioamide component (B) (i.e., at least one selected from the group consisting of the following compounds (B2-1), (B2-2), and (B2-3)) in a proportion such that the peak area ratio [thioamide component (B) / polythiol component (A)] determined by HPLC analysis is 8.75 area. Here, in thioamide B201, one, two, or three of the four X groups in one molecule are -S-C(=S)-NH ２ It is a group, and the rest is a mercapto group (-SH group). 【0211】 【0212】 【0213】 Furthermore, sodium hydrogen sulfide (NaSH) is an example of a sulfur-containing compound (2) (specifically, in formula (2), M １(where is a sodium atom, and m, k, and n are all 1 in a sulfur-containing compound), and sodium hydroxide (NaOH) is an example of a basic compound (3) (specifically, in formula (3), M ２ It is a basic compound in which the atom is sodium and both p and q are 1. 【0214】 <<Preparation of Polymerizable Composition>> XDI composition X1 (52 parts by mass), which is one embodiment of the polyiso(thio)cyanate composition as described above, dibutyltin dichloride (0.015 parts by mass) as a curing catalyst, Zerec UN (product of Stepan, trade name; acidic phosphate ester) (0.10 parts by mass) as a release agent, and Biosorb 583 (manufactured by Kyodo Yakuhin Co., Ltd.; ultraviolet absorber) (1.5 parts by mass) as an ultraviolet absorber were mixed and dissolved at 20°C. The raw material composition 201 (48 parts by mass) obtained above was then charged and mixed to obtain a polymerizable composition as a homogeneous liquid. 【0215】 In XDI composition X1, gas chromatography measurements were performed under GC condition 1 and GC condition 2 as described above. The results showed that the peak area of ​​compound (N1) was 0.20 ppm or more (specifically 600 ppm) relative to the peak area 1 of xylylene diisocyanate, the peak area of ​​compound (N2) was 0.05 ppm or more (specifically 18 ppm) relative to the peak area 1 of xylylene diisocyanate, and the peak area of ​​compound (N3) was 0.10 ppm or more (specifically 100 ppm) relative to the peak area 1 of xylylene diisocyanate. 【0216】<<Manufacturing of Resin Molded Articles>> The polymerizable composition described above was degassed at 600 Pa for 1 hour. The degassed polymerizable composition was filtered through a 1 μm Teflon® filter, and the filtrate was injected between a pair of glass molds fixed with tape. The pair of glass molds was then placed in an oven, and the oven temperature was set to 10°C. Next, the oven temperature was raised from 10°C to 120°C over 38 hours. Through this process, the monomers (polyisocyanate compounds and polythiol compounds) in the polymerizable composition were polymerized, and a molded article containing resin (i.e., a cured product of the polymerizable composition) was formed between the pair of glass molds. Subsequently, the oven was cooled, and after cooling, the pair of glass molds were removed from the oven, and then the molded article containing resin (hereinafter referred to as the resin molded article) was removed from the pair of glass molds. A flat resin molded article (i.e., a lens) with a thickness of 9 mm was obtained. The obtained resin molded article was annealed at 120°C for 1 hour. 【0217】 ≪Evaluation of Yellowness Index (YI) of Resin Molded Products≫ The yellowness index (YI) of the resin molded products after the above annealing was measured using a Konica Minolta CM-5 spectrophotometer. The lower the yellowness index (YI) of the resin molded product, the better the hue of the resin molded product. The results are shown in Table 3. 【0218】[Example 201] <<Production of Polythiol Composition (Base Treatment)>> Monoethanolamine (MEA) (50 parts by mass) as a base (i.e., a basic compound) was added to the aforementioned raw material composition 201 (i.e., the polythiol composition of Comparative Example 201) (200 parts by mass). The resulting mixture was stirred at 60°C for 30 minutes, then degassed water (dissolved oxygen concentration 2 ppm) (100 parts by mass) was added, and the mixture was stirred at 60°C for 30 minutes. After standing, the mixture was separated into an aqueous layer and an organic layer to obtain the organic layer, thus performing base treatment of the raw material composition 201. This base treatment was repeated twice. To the obtained organic layer, 100 parts by mass of degassed water (dissolved oxygen concentration 2 ppm) was added and washed at 35°C to 43°C for 15 minutes. Then, acid washing was performed twice with 125 parts by mass of 35% hydrochloric acid water at 35°C to 43°C for 30 minutes each, followed by five washes with 125 parts by mass of degassed water (dissolved oxygen concentration 2 ppm) at 35°C to 45°C for 15 minutes each. After washing, trace amounts of water were removed from the organic layer under reduced heating pressure, and then a polythiol composition was obtained by vacuum filtration using a 3 μm PTFE type membrane filter, with a peak area ratio [thioamide component (B) / polythiol component (A)] of the values ​​shown in Table 2. 【0219】 Using the obtained polythiol composition, polymerizable compositions, resin molded articles, and the yellowness of the resin molded articles were manufactured in the same manner as in Comparative Example 201. The results are shown in Table 3. 【0220】 【0221】 As shown in Table 3, in Example 201, the peak area ratio [thioamide component (B) / polythiol component (A)] in the raw material composition 201 was reduced by base treatment, and as a result, a polythiol composition with a peak area ratio [thioamide component (B) / polythiol component (A)] of 3 area % or less was obtained. In Example 201, a resin molded article with reduced yellowness (YI) was produced using the obtained polythiol composition. 【0222】The disclosure of Japanese Patent Application No. 2024-218887, filed on 13 December 2024, 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 were specifically and individually noted to be incorporated by reference.

Claims

1. A polythiol composition comprising: a polythiol component (A) selected from the group consisting of polythiol compounds represented by the following formula (A); and a thioamide component (B) selected from the group consisting of thioamide compounds represented by the following formula (B), wherein the peak area ratio [thioamide component (B) / polythiol component (A)] measured by high-performance liquid chromatography is 3 area % or less. [In formulas (A) and (B), R １ [where represents an organic group with 1 to 30 carbon atoms and (m+n) valency, where n is an integer from 1 to 8, and m is an integer from 0 to 8.] 2. R in formulas (A) and (B) １ The polythiol composition according to claim 1, wherein the group comprises the following structure (RS1). [In the structure (RS1), the eight asterisks (*) each represent a bond location.] 3. R ​​in formulas (A) and (B) １ However, the residue obtained by removing (m+n) mercapto groups from 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, the residue obtained by removing (m+n) mercapto groups from 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, the residue obtained by removing (m+n) mercapto groups from 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, the residue obtained by removing (m+n) mercapto groups from 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, the residue obtained by removing (m+n) mercapto groups from 2,5-bismercaptomethyl-1,4-dithiane, or The polythiol composition according to claim 1, wherein the residue is obtained by removing (m+n) mercapto groups from bis(2-mercaptoethyl) sulfide.

4. The polythiol composition according to claim 1, wherein the peak area ratio [thioamide component (B) / polythiol component (A)] is 0.001 area % or more.

5. A polymerizable composition comprising the polythiol composition according to any one of claims 1 to 4, and a polyiso(thio)cyanate compound.

6. The polymerizable composition according to claim 5, further comprising thiol compound XS, which is a thiol compound other than the polythiol component (A).

7. The thiol compound XS is methanedithiol, 1,2-ethanedithiol, 1,2,3-propanetrithiol, pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), tetrakis(mercaptomethylthiomethyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, bis(2-mercaptoethyl)sulfide The polymerizable composition according to claim 6, which is at least one selected from the group consisting of bis(2,3-dimercaptopropyl) sulfide, 2,5-dimercaptomethyl-1,4-dithiane, 2,5-dimercapto-1,4-dithiane, 2,5-dimercaptomethyl-2,5-dimethyl-1,4-dithiane, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, and 4,6-bis(mercaptomethylthio)-1,3-dithiane.

8. The polymerizable composition according to claim 5, wherein the polyiso(thio)cyanate compound comprises at least one selected from the group consisting of pentamethylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, bis(isocyanatomethyl)cyclohexane, bis(isocyanatocyclohexyl)methane, 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and phenylene diisocyanate.

9. A polyiso(thio)cyanate composition comprising the polyiso(thio)cyanate compound, wherein the polyiso(thio)cyanate composition comprises xylylene diisocyanate and at least one compound selected from the group consisting of the following compounds (N1), (N2), and (N3), wherein if the polyiso(thio)cyanate composition comprises compound (N1), the peak area of ​​compound (N1) in gas chromatography measurement is 0.20 ppm or more relative to the peak area of ​​xylylene diisocyanate, and if the polyiso(thio)cyanate composition comprises compound (N2), the peak area of ​​compound (N2) in gas chromatography measurement is 0.05 ppm or more relative to the peak area of ​​xylylene diisocyanate. The polymerizable composition according to claim 5, wherein, when the polyiso(thio)cyanate composition contains the compound (N3), the peak area of ​​the compound (N3) in gas chromatography measurement is 0.10 ppm or more relative to the peak area of ​​xylylene diisocyanate (1).

10. A resin comprising a cured product of the polymerizable composition according to claim 5.

11. A molded article comprising the resin described in claim 10.

12. An optical material comprising the resin described in claim 10.

13. A lens comprising the resin described in claim 10.

14. A method for producing a polythiol composition according to any one of claims 1 to 4, comprising: preparing a raw material composition containing the polythiol component (A) and the thioamide component (B); and obtaining the polythiol composition by reacting the raw material composition in the presence of a basic compound.

15. A method for producing a polythiol composition according to claim 14, wherein the basic compound comprises an amine compound having a pKa in the range of 4 to 12.

16. A method for producing a polythiol composition according to claim 14, wherein the basic compound comprises an amine compound containing at least one of a primary amino group and a secondary amino group.

17. The step of preparing the raw material composition includes reacting an isothiouronium salt (1) represented by the following formula (1) in the presence of a sulfur-containing compound (2) represented by the following formula (2) to obtain the raw material composition. The method for producing a polythiol composition according to claim 14. [In formula (1), R １ represents a (m + n)-valent organic group having 1 to 30 carbon atoms, and R ２ , R ３ , and R ４ each independently represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms. n represents an integer from 1 to 8, m represents an integer from 0 to 8, and X represents a halogen atom. When there are a plurality of R ２ in formula (1), the plurality of R ２ may be the same or different. When there are a plurality of R ３ in formula (1), the plurality of R ３ may be the same or different. When there are a plurality of R ４ in formula (1), the plurality of R ４ may be the same or different. When there are a plurality of X in formula (1), the plurality of X may be the same or different. In formula (2), M １ represents an alkali metal atom, an alkaline earth metal atom, or NH ４ ＋ , m1 represents an integer from 1 to 3, n1 represents an integer from 1 to 3, and k represents an integer from 0 to 3. ] 18. A method for producing a thiol compound according to claim 17, comprising the steps of: reacting a compound (Px) represented by the following formula (Px) with a thiourea compound (4) represented by the following formula (4) to produce the isothiouronium salt (1); and reacting the isothiouronium salt (1) in the presence of the sulfur-containing compound (2) to obtain the raw material composition. [In formula (Px), R Ｘ represents an organic group with 1 to 30 carbon atoms and an (m+n) valency, where n is an integer from 1 to 8, m is an integer from 0 to 8, and A represents a hydroxyl group or a halogen atom. If there are multiple A's in formula (Px), the multiple A's may be the same or different. In formula (4), R ２ , R ３ , and R ４ Each of these independently represents either a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms.

19. A method for producing a polythiol composition according to claim 14, wherein the step of preparing the raw material composition comprises reacting an isothiouronium salt (1) represented by the following formula (1) with a sulfur-containing compound (2) represented by the following formula (2) and at least one selected from the group consisting of a basic compound (3) represented by the following formula (3), a basic compound (X) represented by the following formula (X), and ammonia, to obtain the raw material composition. [In formula (1), R １ R represents an organic group with 1 to 30 carbon atoms and an (m+n) valency. ２ , R ３ , and R ４ Each of these independently represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, n represents an integer from 1 to 8, m represents an integer from 0 to 8, and X represents a halogen atom. In formula (1), R ２ If multiple R ２ They may be the same or different, and R in equation (1) ３ If multiple R ３ They may be the same or different, and R in equation (1) ４ If multiple R ４ X may be the same or different, and if there are multiple X in equation (1), the multiple X may be the same or different. In equation (2), M １ These are alkali metal atoms, alkaline earth metal atoms, or NH ４ ＋ In equation (3), M ２ These are alkali metal atoms, alkaline earth metal atoms, or NH ４ ＋ In equation (X), M ３ 'r' represents an alkali metal atom or alkaline earth metal atom, r represents an integer between 1 and 2, and s represents an integer between 0 and 1.

20. A method for producing a thiol compound according to claim 19, comprising the steps of: reacting a compound (Px) represented by the following formula (Px) with a thiourea compound (4) represented by the following formula (4) to produce the isothiouronium salt (1); and reacting the isothiouronium salt (1) with the sulfur-containing compound (2) and at least one selected from the group consisting of the basic compound (3), the basic compound (X), and ammonia to obtain the raw material composition. [In formula (Px), R Ｘ represents an organic group with 1 to 30 carbon atoms and an (m+n) valency, where n is an integer from 1 to 8, m is an integer from 0 to 8, and A represents a hydroxyl group or a halogen atom. If there are multiple A's in formula (Px), the multiple A's may be the same or different. In formula (4), R ２ , R ３ , and R ４ Each of these independently represents either a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms.

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