Method for producing polythiol composition, and use application thereof

Abstract

Provided is a method for producing a polythiol composition, the method comprising: a preparation step for preparing a crude polythiol composition that is a polythiol composition that is not purified yet; and a purification step for purifying the crude polythiol composition with a solvent X comprising an alkylene glycol to produce a polythiol composition.

Description

Method for producing polythiol composition and its application

[0001] The present disclosure relates to a method for producing a polythiol composition and its applications.

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

[0003] Thiourethane resins are known as one type of resin for lenses. Patent Documents 1 and 2 disclose a method for producing a polythiol compound, which is one of the raw materials for thiourethane resins, and a polymerizable composition for optical materials (e.g., a polymerizable composition for lenses) containing a polythiol compound. Patent Documents 3 and 4 also disclose a polythiol composition that contains a polythiol compound and has a reduced content of nitrogen-containing compounds, as a polythiol composition that can be used to produce high-quality lenses. Patent Documents 3 and 4 also disclose a polymerizable composition for optical materials (e.g., a polymerizable composition for lenses) containing a 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] However, there are cases where it is desired to further improve the pot life of a polymerizable composition that is used in the production of a thiourethane resin and contains a polythiol composition.

[0006] An object of one aspect of the present disclosure is to provide a method for producing a polythiol composition that can improve the pot life of a polymerizable composition containing the polythiol composition, and applications thereof.

[0007] Means for solving the above problems include the following aspects: <1> A method for producing a polythiol composition, comprising: a preparation step of preparing a crude polythiol composition that is a polythiol composition before purification; and a purification step of purifying the crude polythiol composition with a solvent X containing alkylene glycol to obtain a polythiol composition. <2> The method for producing a polythiol composition according to <1>, wherein the crude polythiol composition satisfies at least one of the following conditions: the crude polythiol composition comprises a polythiol component A1 that is a polythiol compound represented by the following formula (5): and a compound (NA1) in which at least one mercapto group in the polythiol component A1 has been replaced with a group represented by the following formula (N1): and the crude polythiol composition comprises a polythiol component A2 that is at least one selected from the group consisting of a polythiol compound represented by the following formula (6): a polythiol compound represented by the following formula (7):

[0008]

[0009] In formula (N1), * represents a bonding position.

[0010] <3> The method for producing a polythiol composition according to <2>, wherein the crude polythiol composition includes the polythiol component A1 and the compound (NA1), and the preparation step includes: reacting 2-mercaptoethanol with an epihalohydrin compound represented by the following formula (1) to obtain a polyalcohol compound represented by the following formula (2): reacting the polyalcohol compound represented by the formula (2) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt; and adding a basic compound to the reaction solution containing the isothiuronium salt to hydrolyze the isothiuronium salt to obtain the crude polythiol composition.

[0011]

[0012] In formula (1), X represents a halogen atom.

[0013] <4> The method for producing a polythiol composition according to <2>, wherein the crude polythiol composition includes the polythiol component A2 and the compound (NA2), and the preparing step includes: reacting 2-mercaptoethanol with an epihalohydrin compound represented by the following formula (1) to obtain a compound represented by the following formula (3): reacting the compound represented by formula (3) with sodium sulfide to obtain a polyalcohol compound represented by the following formula (4): reacting the polyalcohol compound represented by formula (4) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt: and adding a basic compound to the reaction solution containing the isothiuronium salt to hydrolyze the isothiuronium salt to obtain the crude polythiol composition.

[0014]

[0015] In formula (1), X represents a halogen atom.

[0016] <5> The method for producing a polythiol composition according to any one of <1> to <4>, wherein the solvent X includes at least one selected from the group consisting of ethylene glycol and propylene glycol. <6> The method for producing a polythiol composition according to any one of <1> to <5>, wherein the preparing step includes preparing a toluene solution of the crude polythiol composition, and the purifying step includes mixing the toluene solution with the solvent X, thereby purifying the crude polythiol composition in the toluene solution with the solvent X. <7> The method for producing a polythiol composition according to any one of <1> to <6>, wherein the purifying step includes purifying the crude polythiol composition with the solvent X to obtain a polythiol composition, and acid-washing the obtained polythiol composition. <8> A method for producing a polymerizable composition, comprising: a step of producing a polythiol composition by the method for producing a polythiol composition according to any one of <1> to <7>; and a step of mixing the polythiol composition with a polyisocyanate compound to obtain a polymerizable composition containing the polythiol composition and the polyisocyanate compound.

[0017] <9> The step of obtaining a polymerizable composition is a step of obtaining a polymerizable composition containing the polythiol composition and the polyisocyanate composition by mixing the polythiol composition with a polyisocyanate composition containing the polyisocyanate compound, wherein the polyisocyanate composition contains 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, when the polyisocyanate composition contains the compound (N1), the peak area of ​​the compound (N1) measured by high performance liquid chromatography is 0.20 ppm or more relative to 100 ppm of the peak area of ​​xylylene diisocyanate, and when the polyisocyanate composition contains the compound (N2), the peak area of ​​the compound (N2) measured by high performance liquid chromatography is 0.05 ppm or more relative to 100 ppm of the peak area of ​​xylylene diisocyanate, <8> The method for producing a polymerizable composition according to <8>, wherein, when the polyisocyanate composition contains the compound (N3), a peak area of ​​the compound (N3) measured by high performance liquid chromatography is 0.10 ppm or more relative to 100 ppm of a peak area of ​​xylylene diisocyanate.

[0018]

[0019] <10> A method for producing a resin, comprising: a step of producing a polymerizable composition by the method for producing a polymerizable composition according to <8>; and a step of curing the polymerizable composition to obtain a resin.

[0020] <11> A polythiol composition comprising, as a main component, at least one polythiol component A2 selected from the group consisting of a polythiol compound represented by the following formula (6), a polythiol compound represented by the following formula (7), and a polythiol compound represented by the following formula (8), and also comprising a compound (NA2) in which at least one mercapto group in the polythiol component A2 has been replaced with a group represented by the following formula (N1), wherein, in high performance liquid chromatography measurement, the peak area of ​​the compound (NA2) is 0.50 to 1.50, relative to 100, of the total peak area of ​​the compounds contained in the polythiol composition.

[0021]

[0022] In formula (N1), * represents a bonding position.

[0023] <12> A polymerizable composition comprising the polythiol composition according to <11> and a polyisocyanate compound. <13> The present invention relates to a polyisocyanate composition containing the polyisocyanate compound, wherein the polyisocyanate composition contains 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, when the polyisocyanate composition contains the compound (N1), the peak area of ​​the compound (N1) measured by high performance liquid chromatography is 0.20 ppm or more relative to 100 of the peak area of ​​xylylene diisocyanate; when the polyisocyanate composition contains the compound (N2), the peak area of ​​the compound (N2) measured by high performance liquid chromatography is 0.05 ppm or more relative to 100 of the peak area of ​​xylylene diisocyanate; and when the polyisocyanate composition contains the compound (N3), the peak area of ​​the compound (N3) measured by high performance liquid chromatography is 0.10 ppm or more relative to 100 of the peak area of ​​xylylene diisocyanate. The polymerizable composition according to <12>.

[0024]

[0025] According to one aspect of the present disclosure, there is provided a method for producing a polythiol composition that can improve the pot life of a polymerizable composition, and applications thereof.

[0026] In the present disclosure, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In the present disclosure, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved. In the present disclosure, the amount of each component contained in the composition means the total amount of the multiple substances present in the composition, unless otherwise specified, when multiple substances corresponding to each component are present in the composition. In the numerical ranges described in stages in the present disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in the numerical ranges described in the present disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the examples. There may be overlap between multiple embodiments in the present disclosure. That is, the features of one embodiment may be included in another embodiment.

[0027] [Method for Producing Polythiol Composition] The method for producing a polythiol composition of the present disclosure includes: a preparation step of preparing a crude polythiol composition, which is a polythiol composition before purification; and a purification step of purifying the crude polythiol composition with a solvent X containing alkylene glycol to obtain a polythiol composition. The method for producing a polythiol composition of the present disclosure may include other steps as necessary.

[0028] According to the method for producing a polythiol composition of the present disclosure, it is possible to produce a polythiol composition that can improve the pot life of a polymerizable composition containing the polythiol composition. The reason for this effect is presumed to be as follows.

[0029] In a polymerizable composition containing a polythiol composition, if unintended polymerization of polymerizable monomers (e.g., polythiol compounds in the polythiol composition and polyisocyanate compounds described below) progresses during storage, the viscosity of the polymerizable composition may increase during storage, i.e., the pot life of the polymerizable composition may be reduced. The unintended polymerization of the polymerizable monomer is thought to occur when impurities (e.g., compound (NA1) or compound (NA2) described below) that may be unintentionally contained in the polymerizable composition act as a polymerization catalyst. Regarding this problem, the method for producing a polythiol composition of the present disclosure includes a purification step in which a crude polythiol composition, which is a polythiol composition before purification, is purified with a solvent X containing alkylene glycol (hereinafter also referred to as "purification with solvent X" or simply "purification") to obtain a polythiol composition. It is thought that this purification with solvent X removes at least a portion of the impurities from the crude polythiol composition, thereby obtaining a polythiol composition with a reduced impurity content. As a result, it is believed that an increase in viscosity during storage of the resulting polymerizable composition containing the polythiol composition is suppressed (i.e., the pot life of the polymerizable composition is improved).

[0030] According to the purification in the method for producing a polythiol composition of the present disclosure, the above-mentioned effect (improved pot life of the polymerizable composition) can be obtained while suppressing deterioration in the performance of the polythiol composition and the polymerizable composition and resin obtained using the polythiol composition. That is, it is believed that purification with solvent X can selectively remove impurities while reducing the impact on the polythiol compound contained in the polythiol composition.

[0031] Hereinafter, each step that may be included in the method for producing the polythiol composition of the present disclosure will be described.

[0032] <Preparation Step> The method for producing a polythiol composition of the present disclosure includes a preparation step of preparing a crude polythiol composition, which is a polythiol composition before purification. The preparation step may be a step of simply preparing a crude polythiol composition that has been produced in advance, or may be a step of producing a crude polythiol composition.

[0033] (Crude Polythiol Composition, Polythiol Composition) In the present disclosure, a crude polythiol composition is a polythiol composition before purification.

[0034] In the present disclosure, a polythiol composition (including a crude polythiol composition; the same applies hereinafter) refers to a composition containing at least one polythiol compound. The polythiol compound may be any compound containing two or more thiol groups (also known as mercapto groups), and is not particularly limited thereto.

[0035] The polythiol composition may contain components other than the polythiol compound as impurities. The polythiol composition preferably contains at least one polythiol compound as a main component.

[0036] Here, "the polythiol composition contains at least one polythiol compound as a main component" means that the total content of the at least one polythiol compound relative to the total amount of the polythiol composition is 50% or more. The total content of the at least one polythiol compound relative to the total amount of the polythiol composition is preferably 60% or more, more preferably 70% or more, and even more preferably 80% or more.

[0037] Similarly, in the present disclosure, the expression "containing a certain component (hereinafter referred to as "component X") as a "major component" means that the content of component X (when component X consists of two or more compounds, the total content of the two or more compounds) is 50% or more of the total amount of the composition. The content of component X as the major component is preferably 60% or more, more preferably 70% or more, and even more preferably 80% or more of the total amount of the composition.

[0038] The term "%" in the explanation of the above phrase "contains as a major component" means the ratio (area %) of the total area of ​​all peaks of component X (e.g., at least one polythiol compound) to the total area of ​​all peaks of the composition (e.g., a polythiol composition) determined by high performance liquid chromatography.

[0039] Hereinafter, the polythiol compound contained in the polythiol composition will also be referred to as the "polythiol component." The polythiol composition preferably contains at least one selected from the group consisting of 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), 2,5-dimercaptomethyl-1,4-dithiane, bis(2-mercaptoethyl)sulfide, and diethylene glycol bis(3-mercaptopropionate) (hereinafter also referred to as "polythiol component A"). The polythiol composition more preferably contains, as a main component, polythiol component A. In this case, the polythiol composition may contain at least one component other than polythiol component A (e.g., other polythiol compound, component other than polythiol compound, etc.).

[0040] Other polythiol compounds include, for example, methanedithiol, 1,2-ethanedithiol, 1,2,3-propanetrithiol, tetrakis(mercaptomethylthiomethyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, bis(2,3-dimercaptopropyl)sulfide, 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.

[0041] More specific embodiments of the polythiol composition as a raw material for the thiourethane resin include, for example: an embodiment containing 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane (hereinafter also referred to as "polythiol component A1") as a main component; an embodiment containing at least one selected from the group consisting of 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (hereinafter also referred to as "polythiol component A2") as a main component; an embodiment containing pentaerythritol tetrakis(3-mercaptopropionate) (hereinafter also referred to as "polythiol component A3") as a main component; Examples of the polythiol composition include: an embodiment containing polythiol component A1 and polythiol component A3 as the main components; an embodiment containing polythiol component A2 and polythiol component A3 as the main components; and the like. The polythiol composition of each embodiment may contain at least one other component (e.g., other polythiol compound, component other than polythiol compound, etc.) other than the main components. Examples of the other component include the compound (NA1) and compound (NA2) described below.

[0042] The preparation step may involve preparing a toluene solution of the crude polythiol composition. In this case, in the purification step described below, the toluene solution is mixed with a solvent X (i.e., a solvent X containing alkylene glycol), and the crude polythiol composition in the toluene solution is purified with the solvent X. This may more effectively demonstrate the effects of purification using the solvent X. The toluene solution of the crude polythiol composition contains the crude polythiol composition and toluene, but may also contain other components as necessary. It is also possible to purify the crude polythiol composition by directly mixing the crude polythiol composition with the solvent X, without converting it into a toluene solution.

[0043] <Purification Step> The method for producing a polythiol composition of the present disclosure includes a purification step of purifying a crude polythiol composition with a solvent X containing alkylene glycol to obtain a polythiol composition. Purification with solvent X removes impurities (e.g., compounds (NA1) and (NA2) described below) from the crude polythiol composition, yielding a polythiol composition with a reduced amount of the impurities. This results in a polythiol composition that can improve the pot life of the polymerizable composition.

[0044] (Purification with Solvent X) A specific example of the purification with solvent X is washing a liquid composition with solvent X. The temperature of the mixture of crude polythiol composition and solvent X during purification with solvent X is preferably 10°C to 60°C, more preferably 20°C to 60°C, and even more preferably 20°C to 50°C. The time for purification with solvent X is preferably 1 minute to 120 minutes, more preferably 10 minutes to 90 minutes, and even more preferably 20 minutes to 60 minutes.

[0045] As described above, the solvent X contains an alkylene glycol. From the viewpoint of impurity removal by purification, the solvent X preferably contains at least one of ethylene glycol and propylene glycol.

[0046] Solvent X may contain a solvent component other than alkylene glycol. Examples of solvent components other than alkylene glycol include monoalcohols (e.g., monoalcohols having 1 to 6 carbon atoms, such as methanol, ethanol, propanol, and isopropanol). The proportion of alkylene glycol in solvent X (e.g., the total proportion of ethylene glycol and propylene glycol) is preferably 20% by mass to 100% by mass, more preferably 50% by mass to 100% by mass, even more preferably 50% by mass to 100% by mass, and even more preferably 80% by mass to 100% by mass.

[0047] (Acid Washing) The purification step preferably includes: purifying the crude polythiol composition with a solvent X to obtain a polythiol composition; and washing the obtained polythiol composition with an acid.

[0048] The acid used for acid washing is preferably hydrochloric acid. The temperature of the mixture of the polythiol composition and the acid during acid washing is preferably 10°C to 60°C, more preferably 20°C to 60°C, and even more preferably 20°C to 50°C. The acid washing time is preferably 1 minute to 120 minutes, more preferably 5 minutes to 90 minutes, and even more preferably 10 minutes to 70 minutes. The concentration of hydrochloric acid is preferably 25% by mass to 36% by mass, and more preferably 30% by mass to 36% by mass.

[0049] The purification step may further include washing the polythiol composition with water and / or alkali, in addition to washing the polythiol composition with an acid. The water washing and / or alkali washing is preferably carried out after the acid washing. For the water washing, deaerated water having an oxygen concentration of 5 mg / L or less can preferably be used. The alkali washing can be carried out by adding an alkaline aqueous solution and stirring preferably at a temperature in the range of 20°C to 50°C, preferably for 10 minutes to 3 hours. Ammonia water is preferred as the alkaline aqueous solution. The concentration of the ammonia water is preferably 0.1% by mass to 10% by mass, more preferably 0.1% by mass to 1% by mass, and even more preferably 0.1% by mass to 0.5% by mass.

[0050] <Other Steps> The method for producing a polythiol composition of the present disclosure may include other steps as necessary. Examples of other steps include a solvent removal step, a filtration step, a distillation step, and the like, which are performed after the purification step.

[0051] <First embodiment and second embodiment> Hereinafter, a first embodiment and a second embodiment of the method for producing a polythiol composition of the present disclosure will be described. The first embodiment and the second embodiment may have some overlapping parts. That is, one of the first embodiment and the second embodiment may have the features of the other.

[0052] The method for producing a polythiol composition according to the present disclosure preferably satisfies at least one of the following first and second embodiments. The first embodiment is an embodiment in which a crude polythiol composition includes: a polythiol component A1 that is a polythiol compound represented by the following formula (5) (i.e., 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane); and a compound (NA1) in which at least one of the mercapto groups in polythiol component A1 has been replaced with a group represented by the following formula (N1). The second embodiment is an embodiment in which the crude polythiol composition comprises: a polythiol component A2 that is at least one selected from the group consisting of a polythiol compound represented by the following formula (6) (i.e., 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane), a polythiol compound represented by the following formula (7) (i.e., 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane), and a polythiol compound represented by the following formula (8) (i.e., 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane); and a compound (NA2) in which at least one of the mercapto groups in polythiol component A2 has been replaced with a group represented by the following formula (N1).

[0053]

[0054] In formula (N1), * represents a bonding position.

[0055] (First embodiment) In the first embodiment, a crude polythiol composition includes a polythiol component A1 and a compound (NA1). The crude polythiol composition in the first embodiment preferably includes the polythiol component A1 as a main component.

[0056] The compound (NA1) in the first embodiment is a compound in which at least one of the mercapto groups in the polythiol component A1 has been replaced with a group represented by formula (N1). The compound (NA1) is a reaction by-product generated in the process of producing the polythiol component A1, and is considered to be a compound that can be mixed as an impurity in a crude polythiol composition primarily composed of the polythiol component A1. The compound (NA1) is a compound having a retention time of 4.3 to 4.8 minutes in HPLC (high performance liquid chromatography) measurement shown in the "Examples" section below. The compound (NA1) is considered to be an impurity that has a catalytic action that promotes the polymerization of monomers in a polymerizable composition. For details of the compound (NA1), reference can be made to WO 2016 / 010065 (particularly the description regarding the "nitrogen-containing compound (b)") and WO 2020 / 41183 (particularly the description regarding the "nitrogen-containing compound (B)").

[0057] In the first embodiment, in the purification step described below, the compound (NA1) is removed from the crude polythiol composition by purification with a solvent X, and a polythiol composition having a reduced content of the compound (NA1) is obtained. This suppresses an increase in viscosity during storage of a polymerizable compound containing the polythiol composition.

[0058] In the above-described HPLC measurement, the peak area of ​​compound (NA1) is preferably 0.01 to 0.30, and more preferably 0.01 to 0.20, relative to the total peak area (100) of the compounds contained in the polythiol composition obtained by the purification step.

[0059] The preparation step in the first embodiment preferably includes: reacting 2-mercaptoethanol with an epihalohydrin compound represented by the following formula (1) to obtain a polyalcohol compound represented by the following formula (2): reacting the polyalcohol compound represented by the formula (2) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt; and adding a basic compound to the reaction solution containing the isothiuronium salt to hydrolyze the isothiuronium salt to obtain a crude polythiol composition.

[0060]

[0061] In formula (1), X represents a halogen atom.

[0062] For the above-described preferred aspects of the preparation step in the first embodiment, reference can be made to WO 2014 / 027427 (particularly, the description of the method for producing a polythiol compound).

[0063] The preferred aspect of the preparation step in the first embodiment includes reacting 2-mercaptoethanol with an epihalohydrin compound represented by formula (1) to obtain a polyalcohol compound represented by formula (2) below.

[0064] In formula (1), X is preferably a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, and more preferably a chlorine atom.

[0065] The reaction temperature of 2-mercaptoethanol with the epihalohydrin compound represented by formula (1) is preferably 10°C to 50°C, more preferably 15°C to 50°C, and even more preferably 25°C to 45°C.

[0066] The amount of 2-mercaptoethanol used is preferably 1.8 to 3 moles, more preferably 1.9 to 2.1 moles, per mole of the epihalohydrin compound represented by formula (1).

[0067] The reaction between 2-mercaptoethanol and the epihalohydrin compound represented by the following formula (1) is preferably carried out in an aqueous solvent, such as water or a mixed solvent of water and a lower alcohol (e.g., methanol or ethanol).

[0068] The reaction between 2-mercaptoethanol and the epihalohydrin compound represented by the following formula (1) is preferably carried out in the presence of a base. Examples of the base include metal hydroxides such as sodium hydroxide and potassium hydroxide; metal carbonates such as sodium carbonate and potassium carbonate; and tertiary amines such as triethylamine and tributylamine. Of these, sodium hydroxide is particularly preferred. In the case of a monovalent base, the amount of the base used is preferably 0.5 mol to 2 mol, more preferably 0.9 mol to 1.1 mol, per mol of the epihalohydrin compound represented by formula (1). In the case of a divalent base, half the amount of the monovalent base used is preferred.

[0069] A preferred aspect of the preparation step in the first embodiment includes reacting a polyalcohol compound represented by formula (2) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt. The amount of thiourea used is preferably 2.7 moles or more, more preferably 2.7 to 6.0 moles, and even more preferably 2.9 to 3.2 moles per mole of the polyalcohol compound represented by formula (2). The acidic conditions are preferably in the presence of hydrochloric acid. The amount of hydrochloric acid used is preferably 3 moles or more, more preferably 3 to 12 moles, and even more preferably 3 to 5 moles per mole of the polyalcohol compound represented by formula (2). The reaction temperature between the polyalcohol compound represented by formula (2) and thiourea is preferably room temperature (25°C) to reflux temperature, more preferably 90°C to 120°C. The reaction time is preferably 1 to 10 hours.

[0070] A preferred aspect of the preparation step in the first embodiment includes adding a basic compound to a reaction solution containing an isothiuronium salt, hydrolyzing the isothiuronium salt, and obtaining a crude polythiol composition. The basic compound is preferably ammonia. In this hydrolysis, an aqueous solution of the basic compound (e.g., aqueous ammonia) may be added to the reaction solution containing the isothiuronium salt. The reaction temperature for hydrolyzing the isothiuronium salt is preferably 15°C to 60°C, more preferably 25°C to 55°C. The basic compound or its aqueous solution is added to the reaction solution containing the isothiuronium salt over a period of preferably 80 minutes or less, more preferably 70 minutes or less, and even more preferably 20 to 60 minutes. After adding the basic compound or its aqueous solution to the reaction solution containing the isothiuronium salt, the hydrolysis reaction is carried out preferably at room temperature to reflux temperature (more preferably 30°C to 80°C), preferably for 1 hour to 8 hours.

[0071] In the process of obtaining a reaction solution containing an isothiuronium salt, when the polyalcohol compound represented by formula (2) is reacted with thiourea in the presence of hydrochloric acid and ammonia is used as a basic compound during hydrolysis of the isothiuronium salt, the amount of ammonia used per mole of hydrochloric acid is preferably 1 mole or more, more preferably 1 mole to 3 moles.

[0072] It is preferable to add an organic solvent to the reaction solution containing the isothiuronium salt before adding a basic compound or an aqueous solution thereof. Examples of the organic solvent include toluene, xylene, chlorobenzene, dichlorobenzene, etc. Among them, toluene is preferred. By adding toluene as the organic solvent, a toluene solution of the crude polythiol composition is obtained. As a result, as described above, the effect of purification by solvent X is more effectively exhibited.

[0073] Second Embodiment In the second embodiment, the crude polythiol composition contains polythiol component A2 and compound (NA2). The crude polythiol composition in the second embodiment preferably contains polythiol component A2 as a main component.

[0074] Compound (NA2) in the second embodiment is a compound in which at least one of the mercapto groups in polythiol component A2 has been replaced with a group represented by formula (N1). Compound (NA2) is a reaction by-product generated in the process of producing polythiol component A2, and is thought to be a compound that can be mixed as an impurity in a crude polythiol composition containing polythiol component A2 as a main component. Compound (NA2) is a compound having a retention time of 6.5 minutes to 8.0 minutes in HPLC (high performance liquid chromatography) measurement shown in the "Examples" section below. Compound (NA2) is thought to be an impurity that has a catalytic action that promotes the polymerization of monomers in the polymerizable composition.

[0075] In the second embodiment, in the purification step described below, compound (NA2) is removed from the crude polythiol composition by purification with solvent X, thereby obtaining a polythiol composition with a reduced content of compound (NA2). This suppresses an increase in viscosity during storage of a polymerizable compound containing the polythiol composition (i.e., improves the pot life of the polymerizable compound containing the polythiol composition).

[0076] In HPLC measurement, the peak area of ​​compound (NA2) is preferably 0.04 to 1.50, more preferably 0.50 to 1.50, and even more preferably 0.50 to 1.00, relative to 100 of the total peak area of ​​the compounds contained in the polythiol composition obtained by the purification step. When the peak area of ​​compound (NA2) is 0.04 or more (more preferably 0.50 or more) relative to 100 of the total peak area of ​​the compounds contained in the polythiol composition, the heat resistance (e.g., glass transition temperature (Tg)) of the resin produced using the polythiol composition is further improved. When the peak area of ​​compound (NA2) is 1.50 or less relative to 100 of the total peak area of ​​the compounds contained in the polythiol composition, an increase in viscosity during storage of a polymerizable compound containing the polythiol composition is further suppressed (i.e., the pot life of a polymerizable compound containing the polythiol composition is further improved).

[0077] The preparation step in the second embodiment preferably includes: reacting 2-mercaptoethanol with an epihalohydrin compound represented by the following formula (1) to obtain a compound represented by the following formula (3); reacting the compound represented by formula (3) with sodium sulfide to obtain a polyalcohol compound represented by the following formula (4); reacting the polyalcohol compound represented by formula (4) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt; and adding a basic compound to the reaction solution containing the isothiuronium salt to hydrolyze the isothiuronium salt to obtain a crude polythiol composition containing polythiol component A2.

[0078]

[0079] In formula (1), X represents a halogen atom.

[0080] For the above-described preferred aspects of the preparation step in the second embodiment, reference can be made to WO 2014 / 027428 (particularly, the description of the method for producing a polythiol compound).

[0081] The preferred aspect of the preparation step in the second embodiment includes reacting 2-mercaptoethanol with an epihalohydrin compound represented by formula (1) to obtain a compound represented by formula (3).

[0082] In formula (1), X is preferably a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, and more preferably a chlorine atom.

[0083] The reaction temperature of 2-mercaptoethanol with the epihalohydrin compound represented by formula (1) is preferably 2° C. to 30° C., more preferably 5° C. to 20° C., and even more preferably 5° C. to 15° C. The reaction time is preferably 2 hours to 10 hours.

[0084] The amount of 2-mercaptoethanol used is preferably 0.5 to 3 moles, more preferably 0.7 to 2.0 moles, and even more preferably 0.9 to 1.1 moles, per mole of the epihalohydrin compound represented by formula (1).

[0085] The reaction between 2-mercaptoethanol and the epihalohydrin compound represented by the following formula (1) is preferably carried out in an aqueous solvent, such as water or a mixed solvent of water and a lower alcohol (e.g., methanol or ethanol).

[0086] The reaction between 2-mercaptoethanol and the epihalohydrin compound represented by the following formula (1) is preferably carried out in the presence of a base. Examples of the base include metal hydroxides such as sodium hydroxide and potassium hydroxide; metal carbonates such as sodium carbonate and potassium carbonate; and tertiary amines such as triethylamine and tributylamine. Of these, sodium hydroxide is particularly preferred. In the case of a monovalent base, the amount of the base used is preferably 0.001 mol to 0.1 mol per 1 mol of the epihalohydrin compound represented by formula (1). In the case of a divalent base, half the amount of the monovalent base used is preferred.

[0087] A preferred aspect of the preparation step in the second embodiment includes reacting a compound represented by formula (3) with sodium sulfide to obtain a polyalcohol compound represented by formula (4). The amount of sodium sulfide used is preferably 0.4 mol to 0.6 mol per 1 mol of the polyalcohol compound represented by formula (3). The reaction temperature is preferably 10°C to 50°C, more preferably 20°C to 40°C. The reaction time is preferably 1 hour to 10 hours.

[0088] A preferred aspect of the preparation step in the second embodiment includes reacting a polyalcohol compound represented by formula (4) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt. The amount of thiourea used is preferably 3.0 moles or more, more preferably 3.0 to 6.0 moles, and even more preferably 4.6 to 5.0 moles per mole of the polyalcohol compound represented by formula (4). The acidic conditions are preferably in the presence of hydrochloric acid. The amount of hydrochloric acid used is preferably 3 moles or more, more preferably 3 to 12 moles per mole of the polyalcohol compound represented by formula (4). The reaction temperature between the polyalcohol compound represented by formula (4) and thiourea is preferably room temperature (25°C) to reflux temperature, more preferably 90°C to 120°C. The reaction time is preferably 1 to 10 hours.

[0089] A preferred aspect of the preparation step in the second embodiment includes adding a basic compound to a reaction solution containing an isothiuronium salt, hydrolyzing the isothiuronium salt, and obtaining a crude polythiol composition. The basic compound is preferably ammonia. In this hydrolysis, an aqueous solution of the basic compound (e.g., aqueous ammonia) may be added to the reaction solution containing the isothiuronium salt. The reaction temperature for hydrolyzing the isothiuronium salt is preferably 20°C to 60°C, more preferably 25°C to 55°C. The basic compound or its aqueous solution is added to the reaction solution containing the isothiuronium salt over a period of preferably 80 minutes or less, more preferably 70 minutes or less, and even more preferably 20 to 60 minutes. After adding the basic compound or its aqueous solution to the reaction solution containing the isothiuronium salt, the hydrolysis reaction is carried out preferably at room temperature to reflux temperature (more preferably 30°C to 80°C), preferably for 1 hour to 8 hours.

[0090] In the process of obtaining a reaction solution containing an isothiuronium salt, when the polyalcohol compound represented by formula (4) is reacted with thiourea in the presence of hydrochloric acid and ammonia is used as a basic compound during hydrolysis of the isothiuronium salt, the amount of ammonia used per mole of hydrochloric acid is preferably 1 mole or more, more preferably 1 mole to 3 moles.

[0091] It is preferable to add an organic solvent to the reaction solution containing the isothiuronium salt before adding a basic compound or an aqueous solution thereof. Examples of the organic solvent include toluene, xylene, chlorobenzene, dichlorobenzene, etc. Among them, toluene is preferred. By adding toluene as the organic solvent, a toluene solution of the crude polythiol composition is obtained. As a result, as described above, the effect of purification by solvent X is more effectively exhibited.

[0092] [Method for Producing Polymerizable Composition] The method for producing a polymerizable composition of the present disclosure includes the steps of producing a polythiol composition by the method for producing a polythiol composition of the present disclosure described above, and mixing at least the polythiol composition with a polyisocyanate compound to obtain a polymerizable composition containing the polythiol composition and the polyisocyanate compound. The method for producing a polymerizable composition of the present disclosure may include other steps as necessary.

[0093] In the method for producing a polymerizable composition of the present disclosure, a polythiol composition is produced by the method for producing a polythiol composition of the present disclosure described above, and therefore, the same effects as those of the method for producing a polythiol composition of the present disclosure are achieved. That is, according to the method for producing a polymerizable composition of the present disclosure, the polymerization reaction between the polythiol composition and the polyisocyanate compound during storage is suppressed, thereby suppressing an increase in viscosity during storage (i.e., suppressing a decrease in pot life).

[0094] <Step of Producing Polythiol Composition> For the step of producing a polythiol composition in the method for producing a polymerizable composition of the present disclosure, the method for producing a polythiol composition of the present disclosure described above can be appropriately referred to.

[0095] <Step of Obtaining Polymerizable Composition> In the step of obtaining a polymerizable composition, at least the polythiol composition and a polyisocyanate compound are mixed to obtain a polymerizable composition containing the polythiol composition and the polyisocyanate compound.

[0096] A preferred embodiment of the polyisocyanate compound used in the step of obtaining the polymerizable composition is the same as the preferred embodiment of the "isocyanate compound as a raw material for a thiourethane resin" described in the section "Method for producing a polythiol composition."

[0097] In the step of obtaining a polymerizable composition, the mixing ratio of the polythiol composition and the polyisocyanate compound is not particularly limited. In the step of obtaining a polymerizable composition, the ratio of the charged mass of the polythiol composition to the charged mass of the polyisocyanate compound (i.e., charged mass [polythiol composition / polyisocyanate compound]) is preferably 0.10 to 10.0, more preferably 0.20 to 5.00, even more preferably 0.50 to 1.50, and even more preferably 0.70 to 1.30. Furthermore, the molar ratio of mercapto groups of the polythiol compound contained in the polythiol composition to isocyanato groups of the polyisocyanate compound (mercapto groups / isocyanato groups) is preferably 0.5 to 3.0, more preferably 0.6 to 2.0, and even more preferably 0.8 to 1.3.

[0098] In the step of obtaining the polymerizable composition, the total charged mass of the polythiol composition and the polyisocyanate compound is not particularly limited, but is preferably 60 mass% or more, more preferably 80 mass% or more, and even more preferably 90 mass% or more, based on the total amount of the polymerizable composition to be produced.

[0099] The step of obtaining the polymerizable composition may be a step of mixing the polythiol composition with a polyisocyanate composition containing a polyisocyanate compound to obtain a polymerizable composition containing the polythiol composition and the polyisocyanate composition.

[0100] Here, the polyisocyanate composition means a composition containing at least one polyisocyanate compound.

[0101] The polyisocyanate composition may contain components other than the polyisocyanate compound as impurities. The polyisocyanate composition preferably contains at least one polyisocyanate compound as a main component. The meaning of "containing as a main component" is as described above.

[0102] The polyisocyanate composition preferably contains xylylene diisocyanate.

[0103] Hereinafter, a polyisocyanate composition containing xylylene diisocyanate will also be referred to as an XDI composition. The XDI composition preferably contains xylylene diisocyanate as a main component.

[0104] The XDI composition preferably contains at least one selected from the group consisting of the following compound (N1), the following compound (N2), and the following compound (N3).

[0105]

[0106] Below, preferred embodiments of the XDI composition will be described from the viewpoint of achieving excellent stability of the polyisocyanate composition and transparency of the resin formed using the polyisocyanate composition.

[0107] When the XDI composition contains compound (N1), it is preferable that the peak area of ​​compound (N1) measured by gas chromatography under the following GC condition 1 is 0.20 ppm or more relative to the peak area 1 of xylylene diisocyanate. -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, and after reaching 220°C, heating to 300°C at 10°C / min Split ratio: pulsed splitless method Injection port temperature: 280°C Detector temperature: 300°C Carrier gas: N ２ 158 kPa, H ２ 55 kPa, Air 45 kPa (constant pressure control) Solvent: Chloroform Sample concentration: 2.0 mass% chloroform solution Injection amount: 2 μL Detection method: FID

[0108] The peak area of ​​the 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 of ​​xylylene diisocyanate 1. The peak area of ​​the compound (N1) is 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 of ​​xylylene diisocyanate 1. The peak area of ​​the compound (N1) can be measured in accordance with the method described in paragraph 0377 of Japanese Patent No. 6373536.

[0109] When the XDI composition contains compound (N2), the peak area of ​​compound (N2) measured by gas chromatography under the following GC condition 2 is preferably 0.05 ppm or more relative to the peak area of ​​xylylene diisocyanate, 1. -GC condition 2- Column: HP-50+, inner diameter 0.25 mm × length 30 m × film thickness 0.25 μm (manufactured by Hewlett-Packard Company) Oven temperature: temperature increased from 50°C to 280°C at a rate of 10°C / min, and held for 6 minutes after reaching 280°C. Split ratio: pulsed splitless method Injection port 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 amount: 1.0 μL Detection method: SIM (monitoring ions: m / z 180, 215) (content ratio of xylylene diisocyanate (XDI))

[0110] The peak area of ​​the compound (N2) is more preferably 0.1 ppm or more, even more preferably 0.3 ppm or more, and even more preferably 0.6 ppm or more, relative to the peak area of ​​xylylene diisocyanate 1. The peak area of ​​the compound (N2) is 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 even more preferably 60 ppm or less, relative to the peak area of ​​xylylene diisocyanate 1. The peak area of ​​the compound (N2) can be measured in accordance with the method described in paragraphs 0375 and 0376 of Japanese Patent No. 6,373,536.

[0111] When the XDI composition contains compound (N3), the peak area of ​​compound (N3) measured by gas chromatography under the above-mentioned GC condition 1 is preferably 0.10 ppm or more relative to the peak area 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 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 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.

[0112] The acid content 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 acid content of the XDI composition is not particularly limited, but the lower limit is, for example, 1 ppm. The acid content of the XDI composition can be measured in accordance with the method described in paragraph 0091 of WO 2021 / 256417. The XDI composition may also contain a stabilizer.

[0113] In the step of obtaining a polymerizable composition, at least the polythiol composition and the polyisocyanate compound are mixed, but if necessary, the polythiol composition and the polyisocyanate compound may be mixed with other components. Furthermore, in the step of obtaining a polymerizable composition, after mixing at least the polythiol composition and the polyisocyanate compound, other components may be added to the mixture. Examples of these other components include polymerization catalysts, internal mold release agents, resin modifiers, chain extenders, crosslinking agents, radical scavengers, light stabilizers, UV absorbers, antioxidants, oil-soluble dyes, fillers, adhesion improvers, antibacterial agents, antistatic agents, dyes, fluorescent brighteners, fluorescent pigments, and inorganic pigments.

[0114] Examples of the polymerization catalyst include tertiary amine compounds, their inorganic or organic acid salts, metal compounds, quaternary ammonium salts, and organic sulfonic acids.

[0115] The internal mold release agent may be an acidic phosphate ester. Examples of the acidic phosphate ester include a phosphate monoester and a phosphate diester, and these may be used alone or in combination of two or more.

[0116] Examples of the resin modifier include episulfide compounds, alcohol compounds, amine compounds, epoxy compounds, organic acids, organic acid anhydrides, olefin compounds including (meth)acrylate compounds, etc. Here, the (meth)acrylate compound means at least one of an acrylate compound and a methacrylate compound.

[0117] In the step of obtaining the polymerizable composition, the above-mentioned components can be mixed in accordance with a conventional method, and the mixing method is not particularly limited.

[0118] [Method for producing resin] The method for producing a resin according to the present disclosure includes the steps of producing a polymerizable composition by the method for producing a polymerizable composition according to the present disclosure described above, and curing the polymerizable composition to obtain a resin. The method for producing a resin according to the present disclosure may include other steps as necessary.

[0119] In the step of obtaining a resin, the polymerizable composition is cured to obtain a resin. The curing of the polymerizable composition can be carried out by polymerizing the monomers in the polymerizable composition (specifically, the polythiol composition and the polyisocyanate compound; the same applies hereinafter). As a pretreatment for polymerization, the polymerizable composition may be subjected to filtration, degassing, or other treatments. The polymerization conditions (e.g., polymerization temperature, polymerization time, etc.) for polymerizing the monomers in the polymerizable composition are appropriately set taking into consideration the composition of the composition, the type and amount of monomers used in the composition, the type and amount of polymerization catalyst used in the composition, and, if a mold described below is used, the properties of the mold. Examples of polymerization temperatures include -50°C to 150°C, 10°C to 150°C, etc. Examples of polymerization times include 1 hour to 200 hours, 1 hour to 80 hours, etc.

[0120] In the step of obtaining the resin, the polymer obtained by polymerization of the monomer may be subjected to a treatment such as annealing, etc. The annealing temperature may be 50°C to 150°C, 90°C to 140°C, or 100°C to 130°C, etc.

[0121] [Method for producing a molded body] The method for producing a molded body of the present disclosure is a method for producing a molded body containing a resin (hereinafter also referred to as a "resin molded body"), and includes the steps of producing a polymerizable composition by the method for producing a polymerizable composition of the present disclosure described above, and curing the polymerizable composition to obtain a molded body containing a resin. The method for producing a molded body of the present disclosure may include other steps as necessary.

[0122] In the step of obtaining a molded article containing a resin, the polymerizable composition is cured to obtain a molded article containing a resin. For preferred conditions for curing the polymerizable composition, i.e., for polymerizing the monomers in the polymerizable composition, see the section "Method for producing a resin" as appropriate.

[0123] An example of polymerization in this step is cast polymerization. In cast polymerization, the polymerizable composition is first injected between molds held together by a gasket, tape, or the like. At this time, degassing, filtration, or the like may be performed as necessary. Next, the monomer in the polymerizable composition injected between the molds is polymerized to harden the composition between the molds and obtain a cured product. The cured product is then removed from the molds to obtain a molded product containing the resin. Polymerization of the monomer may be performed by heating the polymerizable composition. This heating can be performed, for example, using a heating device equipped with a mechanism for heating an object to be heated in an oven, water, or the like.

[0124] [Method for producing optical material, method for producing lens] The method for producing an optical material (e.g., a lens) according to the present disclosure is a method for producing an optical material (e.g., a lens) comprising a molded article containing a resin, and includes the steps of producing a polymerizable composition by the method for producing a polymerizable composition according to the present disclosure described above, and curing the polymerizable composition to obtain a molded article containing a resin. The method for producing an optical material (e.g., a lens; the same applies hereinafter) according to the present disclosure may include other steps as necessary.

[0125] The method for producing an optical material according to the present disclosure is an application of the method for producing a molded article according to the present disclosure. For example, in the method for producing a molded article according to the present disclosure, by appropriately selecting the shape of the mold used in the above-described cast polymerization, a molded article applicable to an optical material (e.g., a lens) can be obtained.

[0126] Examples of optical materials include lenses (for example, eyeglass lenses, camera lenses, and polarized lenses), light-emitting diodes (LEDs), and the like.

[0127] The method for producing an optical material (for example, a lens) according to the present disclosure may include a step of forming a coating layer on one or both sides of a molded body containing a resin.

[0128] Specific examples of the coating layer include a primer layer, a hard coat layer, an antireflection layer, an antifogging coat layer, an antifouling layer, and a water-repellent layer. Each of these coating layers may be formed alone, or a plurality of coating layers may be formed in a multilayer structure. When coating layers are formed on both sides, the same coating layer may be formed on each side, or different coating layers may be formed on each side.

[0129] The components of the coating layer can be appropriately selected depending on the purpose, and examples of the components of the coating layer include resins (e.g., urethane resins, epoxy resins, polyester resins, melamine resins, polyvinyl acetal resins, etc.), infrared absorbers, light stabilizers, antioxidants, photochromic compounds, dyes, pigments, and antistatic agents.

[0130] For details about eyeglass lenses and coating layers, reference can be made as appropriate to the descriptions in publicly known documents such as International Publication No. WO 2017 / 047745.

[0131] [Polymerizable Composition] The polymerizable composition of the present disclosure contains a polythiol composition obtained by the above-described method for producing a polythiol composition of the present disclosure, and a polyisocyanate compound.

[0132] The polymerizable composition of the present disclosure may contain a polyisocyanate composition containing the above-mentioned polyisocyanate compound. The polyisocyanate composition preferably contains xylylene diisocyanate (i.e., is the aforementioned XDI composition). Preferred aspects of the XDI composition (e.g., containing at least one selected from the group consisting of compound (N1), compound (N2), and compound (N3)) are as described in the section "<Step of Obtaining a Polymerizable Composition>" in the method for producing a polymerizable composition of the present disclosure.

[0133] The polymerizable composition of the present disclosure can be produced by the method for producing a polymerizable composition of the present disclosure described above. For preferred embodiments of the polymerizable composition of the present disclosure, the method for producing a polymerizable composition of the present disclosure described above can be appropriately referenced. However, the charged mass [polythiol composition / polyisocyanate compound] is read as the content mass ratio [polythiol composition / polyisocyanate compound], and the total charged mass of the polythiol composition and the polyisocyanate compound is read as the total content mass of the polythiol composition and the polyisocyanate compound.

[0134] [Resin, Molded Article, Optical Material (e.g., Lens)] The resin of the present disclosure is a cured product of the polymerizable composition of the present disclosure described above. The molded article of the present disclosure is a molded article containing the resin of the present disclosure described above. The optical material (e.g., lens) of the present disclosure is an optical material (e.g., lens) containing the resin of the present disclosure described above.

[0135] The resin of the present disclosure, the molded article of the present disclosure, and the optical material (e.g., a lens) of the present disclosure can be produced by the above-described method for producing a resin of the present disclosure, the method for producing a molded article of the present disclosure, and the method for producing an optical material (e.g., a lens) of the present disclosure, respectively. Preferred aspects of the resin of the present disclosure, the molded article of the present disclosure, and the optical material (e.g., a lens) of the present disclosure can be referenced to the above-described preferred aspects of the method for producing a resin of the present disclosure, the method for producing a molded article of the present disclosure, and the method for producing an optical material (e.g., a lens) of the present disclosure, respectively.

[0136] <Preferred Performance of Resin or Molded Article> From the viewpoint of heat resistance, the glass transition temperature Tg of the resin (or molded article) of the present disclosure is preferably 70° C. or higher, more preferably 80° C. or higher, and even more preferably 85° C. or higher. The glass transition temperature Tg may be 130° C. or lower, 120° C. or lower, or 110° C. or lower.

[0137] From the viewpoint of application to optical materials, the refractive index (ne) of the resin (or molded article) of the present disclosure is preferably 1.500 or more, more preferably 1.540 or more, and even more preferably 1.590 or more. There is no particular upper limit to the refractive index (ne), but the upper limit is, for example, 1.750.

[0138] From the viewpoint of application to optical materials, the Abbe number of the resin (or molded article) according to the present disclosure is preferably equal to or greater than 28, and more preferably equal to or greater than 30. There is no particular upper limit to the Abbe number, but the upper limit is, for example, 50, and preferably 45.

[0139] From the viewpoint of application to optical materials, the specific gravity d of the resin (or molded article) of the present disclosure is preferably 1.10 or more, more preferably 1.20 or more. There is no particular upper limit to the specific gravity d, but the upper limit is, for example, 1.50, preferably 1.40.

[0140] A polythiol composition according to one example of the present disclosure is a polythiol composition comprising, as a main component, polythiol component A2, which is at least one type selected from the group consisting of polythiol compounds represented by formula (6) below, polythiol compounds represented by formula (7) below, and polythiol compounds represented by formula (8) below, and also comprising compound (XC) in which at least one of the mercapto groups in polythiol component A2 is replaced with a group represented by formula (N1) below, wherein, in high performance liquid chromatography measurement, the peak area of ​​compound (NA2) is 0.50 to 1.50, relative to 100, of the total peak area of ​​the compounds contained in the polythiol composition.

[0141]

[0142] In formula (N1), * represents a bonding position.

[0143] For the polythiol composition according to one example of the present disclosure, the second embodiment described above can be referenced. In HPLC measurement, the peak area of ​​compound (NA2) is preferably 0.04 to 1.50, more preferably 0.50 to 1.50, and even more preferably 0.50 to 1.00, relative to the total peak area (100) of the compounds contained in the polythiol composition obtained by the purification step. When the peak area of ​​compound (NA2) is 0.04 or more (more preferably 0.50 or more) relative to the total peak area (100) of the compounds contained in the polythiol composition, the heat resistance (e.g., glass transition temperature (Tg)) of the resin produced using the polythiol composition is further improved.

[0144] A polymerizable composition according to one example of the present disclosure contains the polythiol composition according to the above example and a polyisocyanate compound. The polymerizable composition according to one example of the present disclosure may also contain a polyisocyanate composition containing the polythiol composition according to the above example and a polyisocyanate compound. The polyisocyanate composition preferably contains xylylene diisocyanate (i.e., the XDI composition described above). Preferred aspects of the XDI composition (e.g., containing at least one selected from the group consisting of compound (N1), compound (N2), and compound (N3)) are as described in the section "<Step of Obtaining a Polymerizable Composition>" in the method for producing a polymerizable composition according to the present disclosure.

[0145] The polymerizable composition according to one example of the present disclosure can be produced by the method for producing a polymerizable composition according to the present disclosure described above. For preferred embodiments of the polymerizable composition according to one example of the present disclosure, the method for producing a polymerizable composition according to the present disclosure described above can be appropriately referenced. However, the charged mass [polythiol composition / polyisocyanate compound] is read as the content mass ratio [polythiol composition / polyisocyanate compound], and the total charged mass of the polythiol composition and the polyisocyanate compound is read as the total content mass of the polythiol composition and the polyisocyanate compound.

[0146] A resin according to one example of the present disclosure is a cured product of the polymerizable composition according to the example of the present disclosure described above. A molded article according to one example of the present disclosure is a molded article containing the resin according to the example of the present disclosure described above. An optical material (e.g., a lens) according to one example of the present disclosure is an optical material (e.g., a lens) containing the resin of the present disclosure described above. Preferred aspects of the resin according to one example of the present disclosure, the molded article according to one example of the present disclosure, and the optical material according to one example of the present disclosure are the same as the preferred aspects of the resin of the present disclosure, the molded article of the present disclosure, and the optical material of the present disclosure described above.

[0147] Examples of the present disclosure will be shown below, but the present disclosure is not limited to the following examples. Unless otherwise specified, "parts" are by mass and "room temperature" is 25°C.

[0148] Comparative Example 1 Preparation of Crude Polythiol Composition (A1) According to the production method in Example A-1 of WO 2014 / 027427, a toluene solution of crude polythiol composition (A1) containing polythiol component A1 (i.e., a polythiol compound represented by formula (5) (4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane)) as a main component was obtained. Details are shown below.

[0149] A reactor was charged with 125.4 parts by mass of 2-mercaptoethanol and 18.3 parts by mass of degassed water. 99.8 parts by mass of a 32% by mass aqueous sodium hydroxide solution was added dropwise to the reactor at 12°C to 35°C over 40 minutes, and then 73.8 parts by mass of epichlorohydrin as the epihalohydrin compound represented by formula (1) was added dropwise at 29°C to 36°C over 4 hours, followed by stirring for 30 minutes. As a result, NMR data confirmed the production of 1,3-bis(2-hydroxyethylthio)-2-propanol as the polyalcohol compound represented by formula (2). To the liquid in which the production of 1,3-bis(2-hydroxyethylthio)-2-propanol was confirmed, 332.0 parts by mass of 36% by mass hydrochloric acid was added, followed by 183.8 parts by mass of 99.9% pure thiourea, and the mixture was stirred for 3 hours under reflux at 110°C to carry out a thiuronium chloride reaction, yielding a reaction liquid containing an isothiuronium salt. The resulting reaction liquid was cooled to 45°C, and then 355.0 parts by mass of toluene was added thereto, followed by cooling to 30°C. 244.6 parts by mass of a 25% by mass aqueous ammonia solution was added at 30°C to 40°C over 44 minutes, and the mixture was stirred for 3 hours at 54°C to 62°C to carry out a hydrolysis reaction, yielding a toluene solution of crude polythiol composition (A1) composed primarily of polythiol component A1.

[0150] <Purification of Crude Polythiol Composition (A1)> The toluene solution of the crude polythiol composition (A1) obtained above was subjected to acid washing for 1 hour at 35°C to 40°C using 147.8 parts by mass of 36% by mass hydrochloric acid. The toluene solution after the acid washing was washed once with 147.8 parts by mass of degassed water at 35°C to 40°C for 10 minutes. The toluene solution after one washing with degassed water was washed for 10 minutes with 147.8 parts by mass of 0.1% by mass ammonia water. The toluene solution after washing with ammonia water was washed twice with 147.8 parts by mass of degassed water at 35°C to 40°C for 10 minutes. The crude polythiol composition (A1) was purified by the above operations, and a toluene solution of polythiol composition (A1), which was the purified crude polythiol composition (A1), was obtained by this purification.

[0151] The toluene solution of polythiol composition (A1) obtained by the above purification was heated under reduced pressure to remove toluene and trace amounts of water, and then filtered under reduced pressure using a 3.0 μm PTFE-type membrane filter to obtain 200.0 parts by mass of polythiol composition (A1).

[0152] <Evaluation of Polythiol Composition (A1)> The polythiol composition (A1) obtained above was evaluated as follows. The results are shown in Table 1.

[0153] (Check of Appearance) The appearance of the polythiol composition (A1) was visually observed.

[0154] (Yellowness Index (YI)) The polythiol composition (A1) was filled into a 10 mm glass cell, and the yellowness index was determined from the transmittance. The transmittance was measured using a spectrophotometer CM-5 manufactured by Konica Minolta, Inc.

[0155] (Thiol Value) The thiol value [mmol / g] of the polythiol composition (A1) was determined by oxidation-reduction titration using a 0.05 M aqueous iodine solution.

[0156] (Refractive Index) The refractive index of the polythiol composition (A1) was measured using a liquid refractometer RA600 manufactured by Kyoto Electronics Manufacturing Co., Ltd.

[0157] (HPLC Measurement) High performance liquid chromatography (HPLC) measurement of the polythiol composition (A1) obtained above was carried out under the following HPLC measurement conditions. In this HPLC measurement, the contents of the main component polythiol component A1, and compound (NA1) in which at least one of the mercapto groups in polythiol component A1 has been replaced with a group represented by the above formula (N1), were determined (more specifically, the area ratio (area %) relative to the total peak area of ​​the compounds contained in polythiol composition (A1)). Compound (NA1) has a retention time of 4.3 to 4.8 minutes in this measurement.

[0158] - HPLC measurement conditions - A Mightysil RP-18 GP (registered trademark) manufactured by Kanto Chemical Co., Inc. (particle size S: 5 μm, column shape: Φ6 mm × 150 mm, product number: 25477-9) was used as the column, a mixed solution of acetonitrile / 0.01 mol / L-potassium dihydrogen phosphate aqueous solution = 60 / 40 (vol / vol) was used as the mobile phase, a mixed solution of 160 mg of the polythiol composition and 10 mL of acetonitrile was used as the measurement solution, an ultraviolet detector with a measurement wavelength of 230 nm was used as the detector, and the conditions were as follows: column temperature 40°C, flow rate 1.0 mL / min, and injection volume 2 μL.

[0159] <Preparation of Polymerizable Composition> In a flask equipped with a stirrer, the following substances were placed: dibutyltin dichloride (150 ppm by mass with respect to the total amount of the polyisocyanate compound and the polythiol composition (A)) as a polymerization catalyst; Zelec-UN (manufactured by Stepan; acidic phosphate ester) (1000 ppm by mass with respect to the total amount of the polyisocyanate compound and the polythiol composition (A)) as a mold release agent; Tinuvin 329 (manufactured by BASF Japan Ltd.; 2-(2H-benzotriazol-2-yl)-4-tert-octylphenol) (0.05% by mass with respect to the total amount of the polyisocyanate compound and the polythiol composition (A)) as an ultraviolet absorber; m-xylylene diisocyanate (XDI) (52 parts by mass) as a polyisocyanate compound; and the polythiol composition (A1) (48 parts by mass). The mixture was added and stirred at 20°C for 5 minutes to obtain a polymerizable composition.

[0160] <Viscosity Change of Polymerizable Composition> The viscosity (mPa s) of the obtained polymerizable composition at 20°C was measured using a Brookfield B-type viscometer. The viscosity was measured immediately after 5 minutes of stirring and mixing (hereinafter referred to as "0 h"), after 5 minutes of stirring and mixing followed by standing at 20°C for 1 hour (hereinafter referred to as "1 h"), after 5 minutes of stirring and mixing followed by standing at 20°C for 3 hours (hereinafter referred to as "1 h"), after 5 minutes of stirring and mixing followed by standing at 20°C for 5 hours (hereinafter referred to as "1 h"), and after 5 minutes of stirring and mixing followed by standing at 20°C for 7 hours (hereinafter referred to as "1 h"), thereby observing the change in viscosity over time. The smaller the change in viscosity, the better the pot life of the polymerizable composition.

[0161] <Preparation and Viscosity of Catalyst-Free Polymerizable Composition> A flask equipped with a stirrer was charged with m-xylylene diisocyanate (XDI) (52 parts by mass), which is a polyisocyanate compound, and the above polythiol composition (A1) (48 parts by mass), and the mixture was stirred and mixed at 30°C for 8 hours to obtain a catalyst-free polymerizable composition. The viscosity (mPa s) of the obtained catalyst-free polymerizable composition at 30°C was measured using a Brookfield B-type viscometer. The results are shown in Table 1.

[0162] <Production of Resin Molded Article> 52 parts by mass of m-xylylene diisocyanate, 0.015 parts by mass of dibutyltin dichloride as a curing catalyst, 0.10 parts by mass of Zelec UN (product name: Stepan; acidic phosphate ester), and 0.05 parts by mass of Biosorb 583 (product of Kyodo Pharmaceutical; ultraviolet absorber) were mixed and dissolved at 20°C. 48 parts by mass of polythiol composition (A) were added and mixed to obtain a homogeneous solution, yielding a polymerizable composition for producing a resin molded article. The resulting polymerizable composition was degassed at 600 Pa for 1 hour and then filtered through a 1 μm Teflon (registered trademark) filter. The filtered polymerizable composition was poured between a pair of glass molds secured with tape. The pair of glass molds were then placed in an oven, and the oven temperature was set to 10°C. The oven temperature was then raised from 10°C to 120°C over 38 hours. Through the above process, the monomers (polyisocyanate compound and polythiol composition) in the polymerizable composition were polymerized, and a resin molded body containing a thiourethane 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. The resin molded body was then removed from the pair of glass molds to obtain a flat plate-shaped resin molded body with a thickness of 9 mm. The obtained resin molded body was annealed at 120°C for 1 hour.

[0163] <Evaluation of Resin Molded Article> The resin molded article after the annealing was evaluated as follows. The results are shown in Table 1.

[0164] (Check of Appearance) The appearance of the resin molded body was visually observed.

[0165] (Yellow Index (YI), L*, a*, and b*) Using a spectrophotometer CM-5 manufactured by Konica Minolta, Inc., the yellow index (YI), L*, a*, and b* of the resin molded product were measured.

[0166] (Refractive index (ne) and Abbe number (νe)) Using a Pulfrich refractometer KPR-30 manufactured by Shimadzu Corporation, the refractive indexes (ne, nF', nC') of the molded body were measured at wavelengths of 546.1 nm (mercury e-line), 480.0 nm (Cd F'-line), and 643.9 nm (Cd C'-line) at 20° C. Based on these measurement results, the refractive index (ne) and Abbe number (νe) of the molded body were each determined.

[0167] (Heat Resistance) Using a thermomechanical analyzer TMA-60 manufactured by Shimadzu Corporation, the glass transition temperature (Tg) of the resin molded product was measured by the TMA penetration method (50 g load, pin tip 0.5 mmφ, temperature rise rate 10°C / min) and used as an index of heat resistance.

[0168] (Specific Gravity d) The specific gravity d of the molded body was measured at 20°C by the Archimedes method.

[0169] [Example 1] The same procedure as in Comparative Example 1 was carried out, except that in the "purification of crude polythiol composition (A1)", the following purification procedure with solvent X was added before the acid washing with hydrochloric acid. The results are shown in Table 1.

[0170] -Purification with Solvent X- The toluene solution of crude polythiol composition (A1) obtained in "Preparation of crude polythiol composition (A1)" was washed three times with 147.8 parts by mass of ethylene glycol as solvent X at 35 to 40°C for 15 minutes.

[0171] [Example 2] The polythiol composition (A1) (50 parts by mass) obtained in Example 1 and the polythiol composition (A1) (50 parts by mass) obtained in Comparative Example 1 were blended to obtain the polythiol composition (A1) (100 parts by mass) in Example 2. The same operations as in Comparative Example 1 (specifically, the operations after "Evaluation of polythiol composition (A1)") were performed except that the polythiol composition (A1) in Comparative Example 1 was replaced with the polythiol composition (A1) in Example 2. The results are shown in Table 1.

[0172]

[0173] As shown in Table 1, the polythiol compositions (A1) of Examples 1 and 2, which were obtained by purifying the crude polythiol composition (A1) with solvent X, were confirmed to have an effect of suppressing viscosity changes in polymerizable compositions containing the polythiol composition (A1) (i.e., an effect of improving pot life), compared to the polythiol composition (A1) of Comparative Example 1, which was obtained without purifying the crude polythiol composition (A1) with solvent X. It was confirmed that the polythiol compositions (A1) of Examples 1 and 2 had a reduced content of the impurity compound (NA1) compared to the polythiol composition (A1) of Comparative Example 1. From these results, it is believed that in the polymerizable composition of Comparative Example 1, the impurity compound (NA1) functions as a polymerization catalyst, promoting polymerization of the polythiol composition (A1) and the polyisocyanate compound, and that this polymerization causes an increase in viscosity. Compared to Comparative Example 1, in Examples 1 and 2, the content of compound (NA1) in polythiol composition (A1) was reduced, which is thought to have suppressed polymerization of polythiol composition (A1) with the polyisocyanate compound, thereby reducing the increase in viscosity.

[0174] Furthermore, from the evaluation results of the polythiol composition (A1) and the evaluation results of the resin molded body, it was confirmed that in Examples 1 and 2, the performance of the polythiol composition (A1) and the performance of the resin molded body were maintained to the same extent as in Comparative Example 1.

[0175] As described above, in Examples 1 and 2, it was confirmed that the pot life of the polymerizable composition was improved while the performance of the polythiol composition (A1) and the performance of the resin molded product were maintained at the same level as in Comparative Example 1.

[0176] [Example 1X] In Example 1X, the same procedure as in Example 1 was carried out except that the production of the molded body was changed as follows, and the same results as in Example 1 (Table 1) were obtained.

[0177] - Changes from Example 1 - In Example 1, m-xylylene diisocyanate (XDI) (52 parts by mass) was used in producing the molded body, but in Example 1X, this XDI (52 parts by mass) was changed to XDI composition X1 (an amount such that the amount of XDI contained was 52 parts by mass) as the XDI composition described above. XDI composition X1 was produced by adding trace amounts of compound (N1), compound (N2), and compound (N3) to XDI, which is the main component, and mixing them. The XDI composition X1 was subjected to gas chromatography measurement under the above-mentioned GC conditions 1 and 2. As a result, the peak area of ​​the compound (N1) was 0.20 ppm or more (specifically, 600 ppm) relative to the peak area 1 of xylylene diisocyanate, the peak area of ​​the 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 ​​the compound (N3) was 0.10 ppm or more (specifically, 100 ppm) relative to the peak area 1 of xylylene diisocyanate.

[0178] Comparative Example 101 Preparation of Crude Polythiol Composition (A2) A toluene solution of a crude polythiol composition (A2) containing polythiol component A2 as a main component was obtained according to the production method described in Example C-1 of WO 2014 / 027428. Details are shown below.

[0179] Here, the polythiol component A2 is at least one selected from the group consisting of a polythiol compound represented by formula (6) (i.e., 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane), a polythiol compound represented by formula (7) (i.e., 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane), and a polythiol compound represented by formula (8) (i.e., 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane).

[0180] Into a reactor, 89.25 parts by mass of 2-mercaptoethanol, 44.61 parts by mass of degassed water, and 0.58 parts by mass of a 30.7% by mass aqueous sodium hydroxide solution were charged and cooled to 10 ° C. Next, 107.68 parts by mass of epichlorohydrin as the epihalohydrin compound represented by formula (1) was added dropwise at 9 ° C to 11 ° C over 3.9 hours, followed by stirring for 60 minutes to carry out aging. As a result, from NMR data, the production of the compound represented by formula (3) was confirmed. Next, 262.09 parts by mass of a 17.3% by mass aqueous sodium sulfide solution was added dropwise at 28 ° C to 30 ° C over 1.0 hour, followed by stirring for 3.0 hours to carry out aging. As a result, from NMR data, the production of a polyalcohol compound represented by formula (4) was confirmed. Next, 484.6 parts by mass of 36% by mass hydrochloric acid was added, followed by 214.0 parts by mass of 99.9% pure thiourea, and the mixture was stirred for 3 hours under reflux at 110 ° C. to carry out a thiuronium chloride reaction, yielding a reaction solution containing an isothiuronium salt. The resulting reaction solution was cooled to 45 ° C., and then 373.0 parts by mass of toluene was added thereto, cooled to 32 ° C., and 354.2 parts by mass of a 24.6% by mass aqueous ammonia solution was added at 30 ° C. to 38 ° C. over 25 minutes. The mixture was then heated to 60 ° C. and stirred at 60 ° C. for 1 hour to carry out a hydrolysis reaction, yielding a toluene solution of a crude polythiol composition (A2) composed mainly of polythiol component A2.

[0181] <Purification of Crude Polythiol Composition (A2)> The toluene solution of the crude polythiol composition (A2) obtained above was subjected to acid washing using 101.1 parts by mass of 4% by mass hydrochloric acid at 35°C to 40°C for 15 minutes, and then to acid washing using 101.1 parts by mass of 35% by mass hydrochloric acid at 35°C to 40°C for 30 minutes. The toluene solution after the acid washing with 35% by mass hydrochloric acid was subjected to washing five times using 101.1 parts by mass of degassed water at 35°C to 40°C for 30 minutes. The crude polythiol composition (A2) was purified by the above operations, and a toluene solution of polythiol composition (A2), which was the purified crude polythiol composition (A2), was obtained by this purification.

[0182] The toluene solution of polythiol composition (A2) obtained by the above purification was heated under reduced pressure to remove toluene and trace amounts of water, and then filtered under reduced pressure using a 3.0 μm PTFE-type membrane filter to obtain 200.0 parts by mass of polythiol composition (A2).

[0183] <Evaluation of Polythiol Composition (A2)> The polythiol composition (A2) obtained above was evaluated in the same manner as the polythiol composition (A1) in Comparative Example 1. The results are shown in Table 2.

[0184] In the HPLC measurement of Comparative Example 101, the contents of the following compounds (more specifically, the area ratio (area %) relative to the total peak area of ​​the compounds contained in polythiol composition (A2)) were determined: polythiol component A2, which is the main component; compound (NA2) in which at least one of the mercapto groups in polythiol component A2 has been replaced with a group represented by formula (N1) above; and compound (NA2) in which at least one of the mercapto groups in polythiol component A2 has been replaced with a group represented by formula (N1) above. Compound (NA2) has a retention time of 6.5 to 8.0 minutes in this HPLC measurement.

[0185] <Preparation of polymerizable composition and change in viscosity> The same procedure as in Comparative Example 1 was carried out except that the polythiol composition (A1) was changed to the polythiol composition (A2). The results are shown in Table 2.

[0186] <Preparation and Viscosity of Catalyst-Free Polymerizable Composition> The same procedure as in Comparative Example 1 was carried out, except that the polythiol composition (A1) was changed to the polythiol composition (A2). The results are shown in Table 2.

[0187] <Production and Evaluation of Resin Molded Article> The same procedure as in Comparative Example 1 was carried out, except that the polythiol composition (A1) was changed to the polythiol composition (A2). The results are shown in Table 2.

[0188] [Example 101] In "Purification of crude polythiol composition (A2)", the same procedure as in Comparative Example 101 was carried out, except that the following alcohol purification procedure was added before the acid washing with 4% by mass hydrochloric acid. The results are shown in Table 2.

[0189] -Purification with Solvent X- The toluene solution of crude polythiol composition (A2) obtained in "Preparation of crude polythiol composition (A2)" was washed three times with a mixed solvent of 75.8 parts by mass of ethylene glycol and 24.3 parts by mass of methanol at 35°C to 40°C for 15 minutes.

[0190] [Example 102] The polythiol composition (A2) (50 parts by mass) obtained in Example 101 and the polythiol composition (A2) (50 parts by mass) obtained in Comparative Example 101 were blended to obtain the polythiol composition (A2) (100 parts by mass) in Example 102. The same operations as in Comparative Example 101 (specifically, the operations after "Evaluation of polythiol composition (A2)") were performed except that the polythiol composition (A2) in Comparative Example 101 was replaced with the polythiol composition (A1) (blend) in Example 102. The results are shown in Table 2.

[0191] [Example 103] The polythiol composition (A2) (70 parts by mass) obtained in Example 101 and the polythiol composition (A2) (30 parts by mass) obtained in Comparative Example 101 were blended to obtain the polythiol composition (A2) (100 parts by mass) in Example 103. The same operations as in Comparative Example 101 (specifically, the operations after "Evaluation of polythiol composition (A2)") were performed except that the polythiol composition (A2) in Comparative Example 101 was replaced with the polythiol composition (A1) (blend) in Example 103. The results are shown in Table 2.

[0192]

[0193] As shown in Table 2, the polythiol compositions (A2) of Examples 101 to 103, which were obtained by purifying crude polythiol composition (A2) with solvent X, were confirmed to have an effect of suppressing viscosity changes in polymerizable compositions containing polythiol composition (A2) (i.e., an effect of improving pot life), compared to the polythiol composition (A2) of Comparative Example 1, which was obtained without purifying crude polythiol composition (A2) with solvent X. It was confirmed that the polythiol compositions (A2) of Examples 101 to 103 had a reduced content of the impurity compound (NA2) compared to the polythiol composition (A2) of Comparative Example 101. From these results, it is believed that in the polymerizable composition of Comparative Example 101, the impurity compound (NA2) functions as a polymerization catalyst, promoting polymerization of the polythiol composition (A2) and the polyisocyanate compound, and that this polymerization causes an increase in viscosity. Compared to Comparative Example 101, in Examples 101 to 103, the content of compound (NA2) in polythiol composition (A2) was reduced, which is thought to have suppressed polymerization of polythiol composition (A2) with the polyisocyanate compound, thereby reducing the increase in viscosity.

[0194] Furthermore, from the evaluation results of the polythiol composition (A2) and the evaluation results of the resin molded body, it was confirmed that in Examples 101 to 103, deterioration in the performance of the polythiol composition (A2) and the performance of the resin molded body was suppressed compared to Comparative Example 101 (that is, the pot life of the polymerizable composition was improved without causing deterioration in the performance of the polythiol composition (A2) and the performance of the resin molded body).

[0195] Among Examples 101 to 103, in the resin molded articles of Examples 102 and 103 in which the peak area of ​​compound (NA2) was 0.50 to 1.50 relative to 100 of the total peak area of ​​the compounds contained in polythiol composition (A2) in HPLC measurement, it was confirmed that Tg was maintained at a high level and that heat resistance was excellent, compared to the resin molded article of Example 101 in which the peak area of ​​compound (NA2) was less than 0.50 relative to 100 of the total peak area of ​​the compounds contained in polythiol composition (A2).

[0196] [Example 101X] In Example 101X, the same procedure as in Example 101 was carried out except that the production of the molded body was changed as follows, and the same results as in Example 101 (Table 2) were obtained.

[0197] - Changes from Example 101 - In Example 101, m-xylylene diisocyanate (XDI) (52 parts by mass) was used in producing the molded body, but in Example 101X, this XDI (52 parts by mass) was changed to XDI composition X1 (an amount such that the amount of XDI contained was 52 parts by mass) as the XDI composition described above. XDI composition X1 was produced by adding trace amounts of compound (N1), compound (N2), and compound (N3) to XDI, which is the main component, and mixing them. The XDI composition X1 was subjected to gas chromatography measurement under the above-mentioned GC conditions 1 and 2. As a result, the peak area of ​​the compound (N1) was 0.20 ppm or more (specifically, 600 ppm) relative to the peak area 1 of xylylene diisocyanate, the peak area of ​​the 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 ​​the compound (N3) was 0.10 ppm or more (specifically, 100 ppm) relative to the peak area 1 of xylylene diisocyanate.

[0198] The disclosure of Japanese Patent Application No. 2022-153094, filed on September 26, 2022, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A preparation step of preparing a crude polythiol composition that is a polythiol composition before purification; A purification step of purifying the crude polythiol composition with a solvent X containing an alkylene glycol to obtain a polythiol composition; Including, A method for producing a polythiol composition.

2. The crude polythiol composition includes a polythiol component A1 which is a polythiol compound represented by the following formula (5), and a compound (NA1) in which at least one of the mercapto groups in the polythiol component A1 is replaced with a group represented by the following formula (N1): and, The crude polythiol composition includes a polythiol component A2 which is at least one selected from the group consisting of a polythiol compound represented by the following formula (6), a polythiol compound represented by the following formula (7), and a polythiol compound represented by the following formula (8), and a compound (NA2) in which at least one of the mercapto groups in the polythiol component A2 is replaced with a group represented by the following formula (N1). At least one of the following is satisfied: A method for producing the polythiol composition of claim 1. 【Chemistry 1】 In formula (N1), * represents a bonding position.

3. The crude polythiol composition comprises the polythiol component A1 and the compound (NA1), The preparation step includes: A method for producing a polyalcohol compound represented by the following formula (2) by reacting 2-mercaptoethanol with an epihalohydrin compound represented by the following formula (1); reacting the polyalcohol compound represented by the formula (2) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt; adding a base compound to the reaction solution containing the isothiuronium salt to hydrolyze the isothiuronium salt to obtain the crude polythiol composition; Including, A method for producing the polythiol composition according to claim 2. 【Chemistry 2】 [In formula (1), X represents a halogen atom.]

4. The crude polythiol composition comprises the polythiol component A2 and the compound (NA2), The preparation step includes: Reacting 2-mercaptoethanol with an epihalohydrin compound represented by the following formula (1) to obtain a compound represented by the following formula (3); Reacting the compound represented by formula (3) with sodium sulfide to obtain a polyalcohol compound represented by formula (4): reacting the polyalcohol compound represented by the formula (4) with thiourea under acidic conditions to obtain a reaction solution containing an isothiuronium salt; adding a base compound to the reaction solution containing the isothiuronium salt to hydrolyze the isothiuronium salt to obtain the crude polythiol composition; Including, A method for producing the polythiol composition according to claim 2. 【Chemistry 3】 [In formula (1), X represents a halogen atom.]

5. The solvent X contains at least one selected from the group consisting of ethylene glycol and propylene glycol. A method for producing the polythiol composition of claim 1.

6. The preparing step includes preparing a toluene solution of the crude polythiol composition, The purification step includes purifying the crude polythiol composition in the toluene solution with the solvent X by mixing the toluene solution with the solvent X. A method for producing the polythiol composition of claim 1.

7. The purification step comprises: purifying the crude polythiol composition with the solvent X to obtain a polythiol composition; washing the resulting polythiol composition with an acid; Including, A method for producing the polythiol composition of claim 1.

8. A step of producing a polythiol composition by the method for producing a polythiol composition according to any one of claims 1 to 7; A step of mixing the polythiol composition with a polyisocyanate compound to obtain a polymerizable composition containing the polythiol composition and the polyisocyanate compound; A method for producing a polymerizable composition comprising the steps of:

9. the step of obtaining a polymerizable composition is a step of obtaining a polymerizable composition containing the polythiol composition and the polyisocyanate composition by mixing the polythiol composition with a polyisocyanate composition containing the polyisocyanate compound, The polyisocyanate composition comprises: Xylylene diisocyanate, At least one selected from the group consisting of the following compound (N1), the following compound (N2), and the following compound (N3); Including, When the polyisocyanate composition contains the compound (N1), the peak area of ​​the compound (N1) measured by high performance liquid chromatography is 0.20 ppm or more relative to the peak area of ​​xylylene diisocyanate, When the polyisocyanate composition contains the compound (N2), the peak area of ​​the compound (N2) measured by high performance liquid chromatography is 0.05 ppm or more relative to the peak area of ​​xylylene diisocyanate, When the polyisocyanate composition contains the compound (N3), the peak area of ​​the compound (N3) measured by high performance liquid chromatography is 0.10 ppm or more relative to the peak area of ​​xylylene diisocyanate. The method for producing the polymerizable composition according to claim 8 . 【Chemistry 4】

10. A step of producing a polymerizable composition by the method for producing a polymerizable composition according to claim 8; curing the polymerizable composition to obtain a resin; A method for producing a resin comprising the steps of:

11. The polythiol component A2 contains, as a main component, at least one selected from the group consisting of a polythiol compound represented by the following formula (6), a polythiol compound represented by the following formula (7), and a polythiol compound represented by the following formula (8), The polythiol component A2 contains a compound (NA2) in which at least one of the mercapto groups is replaced with a group represented by the following formula (N1): In a high performance liquid chromatography measurement, the peak area of ​​the compound (NA2) is 0.50 to 1.50 relative to the total peak area of ​​the compounds contained in the polythiol composition (100). Polythiol compositions. 【Chemistry 5】 In formula (N1), * represents a bonding position.

12. The polythiol composition of claim 11 ; A polyisocyanate compound; 1. A polymerizable composition comprising:

13. A polyisocyanate composition containing the polyisocyanate compound, The polyisocyanate composition comprises: Xylylene diisocyanate, At least one selected from the group consisting of the following compound (N1), the following compound (N2), and the following compound (N3); Including, When the polyisocyanate composition contains the compound (N1), the peak area of ​​the compound (N1) measured by high performance liquid chromatography is 0.20 ppm or more relative to the peak area of ​​xylylene diisocyanate, When the polyisocyanate composition contains the compound (N2), the peak area of ​​the compound (N2) measured by high performance liquid chromatography is 0.05 ppm or more relative to the peak area of ​​xylylene diisocyanate, When the polyisocyanate composition contains the compound (N3), the peak area of ​​the compound (N3) measured by high performance liquid chromatography is 0.10 ppm or more relative to the peak area of ​​xylylene diisocyanate. The polymerizable composition of claim 12. 【Chemistry 6】

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