Xylene diisocyanate preparations, polymerizable preparations for optical materials, plastics, molded products, optical components and lenses.

Abstract

The invention relates to a xylen diisocyanate composition, a polymerizable composition for optical materials, plastics, molded products, optical components, and lenses capable of stably producing plastics of good thermal resistance. Xylene diisocyanate, the compound represented by the following chemical formula (1), and the compound represented by the following chemical formula (2) are contained in the xylen diisocyanate composition.

Description

Xylylene diisocyanate composition, polymerizable composition for optical materials, resin, molded article, optical element, and lens

[0001] The present invention relates to a xylylene diisocyanate composition, a polymerizable composition for optical materials, a resin, a molded article, an optical element, and a lens.

[0002] BACKGROUND ART Xylylene diisocyanate compositions have been known as raw materials for resins used in various industrial products.

[0003] For example, a xylylene diisocyanate composition has been proposed that contains xylylene diisocyanate and dichloromethyl benzyl isocyanate, and the content of dichloromethyl benzyl isocyanate is 0.6 ppm or more and 60 ppm or less (see, for example, Patent Document 1).

[0004] International Publication No. 2018 / 190290

[0005] Resins produced from xylylene diisocyanate compositions may be required to have excellent heat resistance depending on the purpose and application. However, when resins are produced from the xylylene diisocyanate composition described in Patent Document 1, there is a limit to how much improvement in heat resistance can be achieved.

[0006] Therefore, the present invention provides a xylylene diisocyanate composition that allows stable production of a resin having excellent heat resistance, a polymerizable composition for optical materials, a resin, a molded article, an optical element, and a lens.

[0007] The present invention [1] includes a xylylene diisocyanate composition containing xylylene diisocyanate, a compound represented by the following chemical formula (1), and a compound represented by the following chemical formula (2).

[0008]

[0009]

[0010] The present invention [2] includes the xylylene diisocyanate composition according to the above [1], in which the mass ratio of the compound represented by the chemical formula (1) to the compound represented by the chemical formula (2) is 10,000 or less.

[0011] The present invention [3] includes the xylylene diisocyanate composition according to the above [2], in which the mass ratio of the compound represented by the chemical formula (1) to the compound represented by the chemical formula (2) is less than 3000. The present invention [4] includes the xylylene diisocyanate composition according to any one of the above [1] to [3], further comprising a curing catalyst represented by the following chemical formula (3), in which the molar ratio of the curing catalyst to the compound represented by the chemical formula (1) is 2 or more. (In chemical formula (3), R １ represents a linear alkyl group having 1 to 20 carbon atoms, a branched alkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or a halogen atom. m is an integer of 0 to 5. When m is 2 to 5, multiple R １ may be the same or different. Q represents a carbon atom or a nitrogen atom.) The present invention [5] includes the xylylene diisocyanate composition according to the above [4], wherein the curing catalyst is at least one selected from pyridine, 3-chloropyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 3-ethylpyridine, 2,6-dimethylpyridine, 3,5-dimethylpyridine, 2,4,6-trimethylpyridine, and 2-methylpyrazine.

[0012] The present invention [6] includes a polymerizable composition for optical materials, which comprises the xylylene diisocyanate composition according to any one of the above [1] to [5] and an active hydrogen group-containing component.

[0013] The present invention [7] is a method for manufacturing a mercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane-based mercaptosilane comprising the steps of: 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane; 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane; 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane; 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane; pentaerythritol tetrakis(2-mercaptoacetate); pentaerythritol tetrakis(3-mercaptopropionate); 2,5-bis(mercaptomethyl)-1,4-dithiane; bis(mercaptomethyl)-1,4-dithiane;

[0023] The polymerizable composition for an optical material according to [6] above contains at least one polythiol selected from the group consisting of 1,2,3-tetrakis(mercaptomethylthio)propane, 4,6-bis(mercaptomethylthio)-1,3-dithiane, 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, 3-mercaptomethyl-1,5-dimercapto-2,4-dithiapentane, tris(mercaptomethylthio)methane, and ethylene glycol bis(3-mercaptopropionate).

[0014] The present invention [8] includes a resin that is a cured product of the polymerizable composition for optical materials according to the above [6] or [7].

[0015] The present invention [9] includes a molded article containing the resin described in the above [8].

[0016] The present invention

[10] includes an optical element comprising the molded article according to the above [9].

[0017] The present invention

[11] includes a lens including the optical element according to the above

[10] .

[0018] The xylylene diisocyanate composition of the present invention contains xylylene diisocyanate, the compound represented by the above chemical formula (1), and the compound represented by the above chemical formula (2). Therefore, a resin produced from the above xylylene diisocyanate composition has excellent heat resistance.

[0019] The polymerizable composition for an optical material of the present invention contains the xylylene diisocyanate composition described above. Therefore, a resin produced from the polymerizable composition for an optical material described above has excellent heat resistance.

[0020] The resin, molded article, optical element, and lens of the present invention contain a cured product of the polymerizable composition for optical materials described above, and therefore the resin, molded article, optical element, and lens have excellent heat resistance.

[0021] Figure 1 is a graph showing the correlation between the mass ratio of isocyanatomethylbenzylcarbamic acid chloride to dichloromethylbenzyl isocyanate in the xylylene diisocyanate composition of each Example and the glass transition temperature of the resin. Figure 2 is a graph showing the correlation between the content of isocyanatomethylbenzylcarbamic acid chloride in the xylylene diisocyanate composition of each Example and the glass transition temperature of the resin.

[0022] 1. Xylylene diisocyanate composition The xylylene diisocyanate composition of the present invention is a substantially single compound (i.e., xylylene diisocyanate) containing 98% by mass or more of xylylene diisocyanate as the main component. The xylylene diisocyanate composition of the present invention is defined as a xylylene diisocyanate composition because it contains, as secondary components, a compound represented by the following chemical formula (1) and a compound represented by the following chemical formula (2).

[0023] That is, the xylylene diisocyanate composition of the present invention contains, as essential components, xylylene diisocyanate, a compound represented by the following chemical formula (1), and a compound represented by the following chemical formula (2). The xylylene diisocyanate composition may further contain a curing catalyst.

[0024] Hereinafter, the xylylene diisocyanate composition will be referred to as the XDI composition, and xylylene diisocyanate will be referred to as XDI. Furthermore, the compound (isocyanatomethylbenzylcarbamic acid chloride) shown in the following chemical formula (1) will be referred to as the monocarbamoyl Cl form or the MCC form. Furthermore, the compound (dichloromethylbenzylisocyanate) shown in the following chemical formula (2) will be referred to as DCI.

[0025]

[0026]

[0027] Examples of XDI include 1,2-XDI (o-XDI), 1,3-XDI (m-XDI), and 1,4-XDI (p-XDI).

[0028] One or more of such XDIs may be contained in the XDI composition.

[0029] Of the XDIs, 1,3-XDI (m-XDI) is preferred.

[0030] The content (purity) of XDI is, for example, 98.00% by mass or more, preferably 99.00% by mass or more, more preferably 99.30% by mass or more, and even more preferably 99.60% by mass or more, and for example, 99.95% by mass or less, relative to the total mass of the XDI composition. The content of XDI can be measured in accordance with the method described in paragraphs

[0376] and

[0377] of WO 2018 / 190290.

[0031] The monocarbamoyl Cl form represented by the above chemical formula (1) is isocyanatomethylbenzylcarbamic acid chloride, in which one of the two isocyanate groups in XDI is substituted with a carbamoyl chloride group (—NH—CO—Cl group).

[0032] Examples of monocarbamoyl Cl forms include (2-(isocyanatomethyl)benzyl)carbamic acid chloride, (3-(isocyanatomethyl)benzyl)carbamic acid chloride, and (4-(isocyanatomethyl)benzyl)carbamic acid chloride.

[0033] One or more types of such monocarbamoyl Cl forms may be contained in the XDI composition.

[0034] As will be described in detail later, the monocarbamoyl Cl form is produced as a reaction intermediate of XDI in the production of an XDI composition, and is also produced by the reaction of XDI with hydrogen chloride. The structural isomer of the produced monocarbamoyl Cl form corresponds to the structural isomer of the XDI used as the raw material. For example, in an XDI composition, when the main component is 1,3-XDI, the monocarbamoyl Cl form as a minor component is (3-(isocyanatomethyl)benzyl)carbamic acid chloride.

[0035] Of the monocarbamoyl Cl compounds, (3-(isocyanatomethyl)benzyl)carbamic acid chloride is preferred.

[0036] The content of the monocarbamoyl Cl form is, relative to the total mass of the XDI composition, for example, 1 ppm, preferably 10 ppm or more, more preferably 100 ppm or more, even more preferably 300 ppm or more, particularly preferably 1000 ppm or more, and for example, 10000 ppm or less, preferably 6000 ppm or less, more preferably 4000 ppm or less, even more preferably 2000 ppm or less. The content of the monocarbamoyl Cl form is calculated from the remaining chlorine amount calculated by subtracting the chlorine amount of chlorine-containing components other than the monocarbamoyl Cl form (e.g., DCI and CBI (described below)) from the hydrolyzable chlorine amount (HC, described below) of the XDI composition. When the XDI composition contains both monocarbamoyl Cl and dicarbamoyl compounds, the ratio of the monocarbamoyl Cl to dicarbamoyl compounds is calculated from the difference in the inflection point observed when the XDI composition is titrated with an aqueous solution of an alkali metal hydroxide, where sodium hydroxide or potassium hydroxide is used as the alkali metal hydroxide.

[0037] The mass ratio of the monocarbamoyl Cl form to DCI is, for example, 1 or more, preferably 30 or more, more preferably 100 or more, even more preferably 200 or more, particularly preferably 400 or more, and particularly preferably 800 or more, and for example, 10,000 or less, preferably 6,000 or less, more preferably less than 3,000, even more preferably 1,900 or less, and particularly preferably 950 or less.

[0038] When the mass ratio of the monocarbamoyl Cl body to DCI is equal to or greater than the lower limit, the heat resistance (glass transition temperature Tg) of the resin produced from the XDI composition can be reliably improved. When the mass ratio of the monocarbamoyl Cl body to DCI is equal to or less than the upper limit, the pot life can be sufficiently ensured when the XDI composition is mixed with the active hydrogen group-containing component described below. In particular, when the mass ratio of the monocarbamoyl Cl body to DCI is less than 3,000, the releasability of the resin from the mold can be improved when the resin is produced by a casting method.

[0039] DCI is dichloromethylbenzyl isocyanate, in which one of the two isocyanatomethyl groups in XDI has been substituted with a dichloromethyl group (-CHCl2 group).

[0040] Examples of DCI include 2-dichloromethylbenzyl isocyanate (o-DCI), 3-dichloromethylbenzyl isocyanate (m-DCI), and 4-dichloromethylbenzyl isocyanate (p-DCI).

[0041] One or more of such DCIs may be contained in the XDI composition.

[0042] As will be described in detail later, DCI is a by-product in the production of XDI. The structural isomer of the by-product DCI corresponds to the structural isomer of the produced XDI. For example, in an XDI composition, when the main component is 1,3-XDI, the DCI as a minor component is 3-dichloromethylbenzyl isocyanate.

[0043] Of the DCIs, 3-dichloromethylbenzyl isocyanate (m-DCI) is preferred.

[0044] The content of DCI is, for example, 0.1 ppm or more, preferably 0.6 ppm or more, and for example, 60 ppm or less, preferably 30 ppm or less, more preferably 10 ppm or less, even more preferably 5.0 ppm or less, particularly preferably 3.0 ppm or less, and particularly preferably less than 2.0 ppm, relative to the total mass of the XDI composition. The content of DCI can be measured by gas chromatography analysis in accordance with the method described in the Examples below.

[0045] When the content of DCI is equal to or less than the upper limit, the heat resistance (glass transition temperature Tg) of the resin produced from the XDI composition can be further improved.

[0046] The XDI composition may also contain chloromethyl benzyl isocyanate represented by the following chemical formula (4): Hereinafter, chloromethyl benzyl isocyanate represented by the following chemical formula (4) will be referred to as CBI.

[0047]

[0048] CBI is monochloromethylbenzyl isocyanate, in which one of the two isocyanatomethyl groups in XDI has been substituted with a monochloromethyl group (-CH2Cl group).

[0049] Examples of CBI include 2-chloromethylbenzyl isocyanate (o-CBI), 3-chloromethylbenzyl isocyanate (m-CBI), and 4-dichloromethylbenzyl isocyanate (p-CBI).

[0050] One or more of such CBIs may be contained in the XDI composition.

[0051] As will be described in detail later, CBI is a by-product in the production of XDI. The structural isomer of the by-product CBI corresponds to the structural isomer of the produced XDI. For example, in an XDI composition, when the main component is 1,3-XDI, the CBI as a minor component is 3-chloromethylbenzyl isocyanate.

[0052] Of the CBIs, 3-chloromethylbenzyl isocyanate (m-CBI) is preferred.

[0053] The CBI content is, for example, 0 ppm or more, preferably 0.2 ppm or more, preferably 6 ppm or more, more preferably 100 ppm or more, and for example, 5000 ppm or less, preferably 4000 ppm or less, more preferably 3000 ppm or less, particularly preferably 1600 ppm or less, and particularly preferably 1000 ppm or less, relative to the total mass of the XDI composition. It can be measured in accordance with the method described in paragraphs

[0376] and

[0377] of WO 2018 / 190290.

[0054] When the CBI content is within the above range, the yellowing resistance of the resin produced from the XDI composition can be reliably improved. In particular, when the CBI content is equal to or less than the above upper limit, the yellowing resistance of the resin produced from the XDI composition can be reliably improved, and the mechanical properties of the resin can be improved.

[0055] The concentration of hydrolyzable chlorine (HC) in the XDI composition is, for example, 0.15 ppm or more, preferably 1 ppm or more, more preferably 50 ppm or more, particularly preferably 100 ppm or more, and for example, 3000 ppm or less, preferably 2000 ppm or less, more preferably 1000 ppm or less. The concentration of hydrolyzable chlorine (HC) is measured in accordance with the method for determining hydrolyzable chlorine described in JIS K-1603-3 (2007). The curing catalyst is preferably represented by the following chemical formula (3): In the above chemical formula (3), R １ represents a linear alkyl group having 1 to 20 carbon atoms, a branched alkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or a halogen atom. １ Examples of the linear alkyl group having 1 to 20 carbon atoms represented by the formula (R) include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a pentyl group, a hexyl group, a heptyl group, an n-octyl group, a nonyl group, a decyl group, and a dodecyl group. １Examples of the branched alkyl group having 3 to 20 carbon atoms represented by the formula (R) include an isopropyl group, an isobutyl group, a t-butyl group, an isopentyl group, an isooctyl group, a 2-ethylhexyl group, a 2-propylpentyl group, and an isodecyl group. １ Examples of the cycloalkyl group having 3 to 20 carbon atoms represented by the formula (R) include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. １ is preferably a linear alkyl group having 1 to 20 carbon atoms, more preferably a linear alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group. In the above chemical formula (3), m is an integer of 0 to 5, preferably an integer of 0 to 3, and more preferably an integer of 1 to 3. When m is 2 to 5, multiple R １ may be the same or different. Preferably, a plurality of R １are the same. In the above chemical formula (3), Q represents a carbon atom or a nitrogen atom. Q is preferably a carbon atom. Examples of the curing catalyst represented by the above chemical formula (3) include pyridine, 3-chloropyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 3-ethylpyridine, 2,6-dimethylpyridine, 3,5-dimethylpyridine, 2,4,6-trimethylpyridine, and 2-methylpyrazine. Preferred curing catalysts include 3,5-dimethylpyridine and 2,4,6-trimethylpyridine. The molar ratio of the curing catalyst to the monocarbamoyl Cl form represented by chemical formula (1) is 2 or more, preferably 2.3 or more. When the molar ratio of the curing catalyst to the monocarbamoyl Cl form represented by chemical formula (1) is equal to or greater than the above lower limit, the polymerizable composition for optical materials can be smoothly cured. The molar ratio of the curing catalyst to the monocarbamoyl Cl form represented by chemical formula (1) is 4 or less, preferably 3 or less, and more preferably 2.5 or less. When the molar ratio of the curing catalyst to the monocarbamoyl Cl form represented by chemical formula (1) is equal to or less than the above upper limit, the pot life of the polymerizable composition for optical materials can be ensured. The polymerizable composition for optical materials may contain a curing catalyst other than the above chemical formula (3). Examples of curing catalysts other than the chemical formula (3) include organotin catalysts and Lewis acid catalysts. Examples of organotin catalysts include dialkyltin halides and dialkyltin dicarboxylates. Examples of dialkyltin halides include dibutyltin dichloride and dimethyltin dichloride. Examples of dialkyltin dicarboxylates include dimethyltin diacetate, dibutyltin dioctanoate, and dibutyltin dilaurate.

[0056] 2. Method for Producing XDI Composition Next, a method for producing the XDI composition will be described.

[0057] To produce the XDI composition, for example, a reaction mass is prepared by the method for producing an XDI composition described in paragraphs

[0054] to

[0110] of WO 2018 / 190290, and then the reaction mass is purified so that the contents of at least XDI, monocarbamoyl Cl form, and DCI fall within the above-mentioned ranges.

[0058] To prepare the reaction mass, for example, xylylenediamine and hydrogen chloride are mixed to form xylylenediamine hydrochloride, and then the hydrochloride is reacted with carbonyl chloride (phosgene) (amine hydrochloride phosgenation method).

[0059] Hereinafter, xylylenediamine will be referred to as XDA. Examples of XDA include 1,2-XDA (o-XDA), 1,3-XDA (m-XDA), and 1,4-XDA (p-XDA), and preferably 1,3-XDA (m-XDA).

[0060] In the salt formation step of forming XDA hydrochloride, for example, XDA and hydrogen chloride are mixed in the presence of an inert solvent to produce XDA hydrochloride (salt formation).

[0061] Examples of inert solvents include those described in paragraph

[0059] of WO 2018 / 190290. The inert solvents can be used alone or in combination of two or more. Among the inert solvents, halogenated aromatic hydrocarbons are preferred, and chlorobenzene and dichlorobenzene are more preferred.

[0062] Hydrogen chloride gas is then supplied to the amine solution in which XDA is dissolved in an inert solvent, and the hydrogen chloride gas and the amine solution are then mixed by stirring.

[0063] The mass ratio of XDA to the sum of the masses of XDA and the inert solvent (total amine concentration) is, for example, 3 mass% or more, preferably 5 mass% or more, and for example, 30 mass% or less, preferably 20 mass% or less, more preferably 15 mass% or less.

[0064] The supply ratio of hydrogen chloride is, for example, 2 moles or more and, for example, 10 moles or less, preferably 6 moles or less, and more preferably 4 moles or less, per mole of XDA.

[0065] The salt formation temperature in the salt formation step is, for example, 30° C. or more, preferably 50° C. or more, and for example, 160° C. or less, preferably 150° C. or less. The salt formation pressure (gauge pressure) in the salt formation step is, for example, atmospheric pressure (0 MPaG) or more, preferably 0.01 MPaG or more, and for example, 1.0 MPaG or less, preferably 0.5 MPaG or less.

[0066] As a result, XDA hydrochloride is produced from XDA and hydrogen chloride (hydrochlorination reaction), and a slurry containing XDA hydrochloride is produced.

[0067] Next, carbonyl chloride is supplied to the slurry containing XDA hydrochloride to react the XDA hydrochloride with the carbonyl chloride (isocyanation reaction, phosgenation).

[0068] The supply ratio of carbonyl chloride is, relative to 1 mole of XDA hydrochloride, for example, 4 moles or more, preferably 5 moles or more, more preferably 6 moles or more, and for example, 50 moles or less, preferably 40 moles or less, more preferably 30 moles or less.

[0069] The reaction time of the isocyanation step is, for example, 4 hours or more, preferably 6 hours or more, and for example, 25 hours or less, preferably 20 hours or less, more preferably 15 hours or less.

[0070] The reaction temperature in the isocyanation step is, for example, 90°C or more, preferably 100°C or more, more preferably 110°C or more, and for example, 190°C or less, preferably 180°C or less, more preferably 160°C or less.

[0071] The reaction pressure (gauge pressure) in the isocyanation step exceeds atmospheric pressure (0 MPaG), and is preferably 0.0005 MPaG or more, more preferably 0.001 MPaG or more, even more preferably 0.003 MPaG or more, particularly preferably 0.01 MPaG (10 kPaG) or more, particularly preferably 0.02 MPaG (20 kPaG) or more, most preferably 0.03 MPaG (30 kPaG) or more, and is, for example, 0.6 MPaG or less, preferably 0.4 MPaG or less, more preferably 0.2 MPaG or less.

[0072] The isocyanation step is preferably carried out continuously, i.e., the slurry (XDA hydrochloride) produced in the stirring tank is continuously transferred from the stirring tank to a reaction tank separate from the stirring tank, and the reaction liquid (reaction mass) is continuously removed from the reaction tank while the XDA hydrochloride and carbonyl chloride are reacted in the reaction tank.

[0073] This causes XDA hydrochloride to react with carbonyl chloride to produce XDI as the main component, and a monocarbamoyl Cl compound as a reaction intermediate of XDI.

[0074] Furthermore, as described above, by supplying an excess amount of carbonyl chloride under pressurized conditions and continuously carrying out the isocyanation step of the hydrochloride method, CBI, which is by-produced along with the production of XDI, reacts with chlorine inevitably contained in the carbonyl chloride to produce DCI.

[0075] Next, if necessary, the reaction liquid (reaction mixture) is subjected to a degassing step, a desolvation step, and a detarring step. In the degassing step, excess carbonyl chloride and gases such as by-product hydrogen chloride are removed from the reaction liquid (reaction mixture) using a known degassing tower. In the desolvation step, the inert solvent is distilled off from the reaction liquid using a known distillation tower. In the detarring step, tar components are removed from the reaction liquid using a known detarring apparatus.

[0076] As a result of the above, a reaction mass containing at least XDI, a monocarbamoyl Cl form, and DCI is produced.

[0077] The content of XDI in the reaction mass is, for example, 80.0 mass% or more, preferably 90.0 mass% or more, more preferably 95.0 mass% or more, and for example, 99.0 mass% or less, preferably 98.5 mass% or less, more preferably 98.0 mass% or less.

[0078] The content of monocarbamoyl Cl forms in the reaction mass is, for example, 5 ppm or more, preferably 10 ppm or more, more preferably 20 ppm or more, and for example, 10,000 ppm or less, preferably 5,000 ppm or less, more preferably 3,000 ppm or less.

[0079] The DCI content in the reaction mass is, for example, 1 ppm or more, preferably 2 ppm or more, more preferably 5 ppm or more, and for example, 80 ppm or less, preferably 70 ppm or less, more preferably 50 ppm or less.

[0080] The reaction mass may further contain CBI. When the reaction mass contains CBI, the content of CBI in the reaction mass is, for example, 0.1 mass% or more, preferably 0.3 mass% or more, more preferably 0.5 mass% or more, and for example, 3.0 mass% or less, preferably 1.5 mass% or less, more preferably 1.0 mass% or less.

[0081] Next, the reaction mass (pre-purification composition) is purified to adjust the content ratio of the monocarbamoyl Cl form and DCI to fall within the above-mentioned ranges.

[0082] An example of a method for purifying the reaction mass is distillation. To purify the reaction mass by distillation, for example, low boiling points (low boiling point components) are removed from the reaction mass by distillation, and the reaction mass after removal of the low boiling points is then rectified.

[0083] In the low boiling point removal step, for example, the reaction mass is distilled in a low boiling point removal column to remove the low boiling points.

[0084] Examples of the low boiling point removal tower include a plate tower and a packed tower, preferably a packed tower. The number of theoretical plates of the low boiling point removal tower is, for example, 3 or more, preferably 5 or more, more preferably 7 or more, and for example, 40 or less, preferably 20 or less, more preferably 15 or less.

[0085] The temperature at the bottom of the low boiling separation tower is, for example, 130°C or higher, preferably 140°C or higher, more preferably 150°C or higher, and for example, 200°C or lower, preferably 190°C or lower, more preferably 180°C or lower.

[0086] The top temperature of the low boiling separation tower is, for example, 90°C or higher, preferably 100°C or higher, more preferably 110°C or higher, and for example, 160°C or lower, preferably 150°C or lower, more preferably 140°C or lower.

[0087] The pressure at the top of the low boiling separation tower is, for example, 0.05 kPa or more, preferably 0.1 kPa or more, more preferably 0.2 kPa or more, and for example, 3.0 kPa or less, preferably 2.0 kPa or less, more preferably 1.0 kPa or less.

[0088] The reflux ratio at the top of the low boiling separation tower is, for example, 1 or more, preferably 5 or more, more preferably 10 or more, and for example, 80 or less, preferably 60 or less, more preferably 50 or less.

[0089] The residence time in the low boiling removal tower is, for example, 0.1 hour or more, preferably 0.2 hour or more, more preferably 0.3 hour or more, and for example, 10 hours or less, preferably 5 hours or less, more preferably 3 hours or less.

[0090] From this, low boiling matters are distilled off, and the low boiling mass is obtained as the bottoms.

[0091] Next, in the rectification step, for example, the low boiling mass is distilled in a rectification column to extract a fraction.

[0092] Examples of the rectification column include a plate column and a packed column, and preferably a packed column. The number of theoretical plates of the rectification column is, for example, 1 or more and, for example, 20 or less, preferably 10 or less, more preferably 5 or less.

[0093] The bottom temperature of the rectification column is, for example, 120°C or more, preferably 130°C or more, more preferably 140°C or more, and for example, 190°C or less, preferably 180°C or less, more preferably 170°C or less.

[0094] The top temperature of the rectification column is, for example, 90°C or higher, preferably 110°C or higher, more preferably 130°C or higher, and for example, 180°C or lower, preferably 170°C or lower, more preferably 160°C or lower.

[0095] The pressure at the top of the rectification column is, for example, 0.05 kPa or more, preferably 0.1 kPa or more, more preferably 0.2 kPa or more, and for example, 3.0 kPa or less, preferably 2.0 kPa or less, more preferably 1.0 kPa or less.

[0096] The top reflux ratio of the rectification column is, for example, 0.1 or more, preferably 0.2 or more, more preferably 0.3 or more, and for example, 50 or less, preferably 20 or less, more preferably 10 or less.

[0097] The residence time in the rectification column is, for example, 0.2 hours or more, preferably 0.5 hours or more, more preferably 1.0 hour or more, and for example, 20 hours or less, preferably 10 hours or less.

[0098] As a result, the XDI composition is extracted as a fraction, and the contents of XDI, monocarbamoyl Cl form, and DCI in the XDI composition can be adjusted to fall within the above-mentioned ranges. The DCI content in the XDI composition can also be adjusted by adding DCI to the XDI composition after rectification. Furthermore, the monocarbamoyl Cl content in the XDI composition can also be adjusted by supplying hydrogen chloride gas to the XDI composition after rectification.

[0099] Furthermore, experimentally, as in the examples described below, an XDI composition containing XDI and DCI but substantially no monocarbamoyl Cl isomers (an XDI composition free of MCC isomers) can be prepared, and hydrogen chloride gas can be supplied to the XDI composition free of MCC isomers to produce an XDI composition containing XDI, monocarbamoyl Cl isomers, and DCI in the above-mentioned ratios.

[0100] To prepare an XDI composition free of MCC compounds, for example, in the low-boiling point removal step and the rectification step, the monocarbamoyl Cl compounds contained in the reaction mass are thermally decomposed and converted into XDI. The content of the monocarbamoyl Cl compounds in the XDI composition free of MCC compounds is, for example, less than 0.05 ppm, preferably 0 ppm.

[0101] Next, hydrogen chloride gas is supplied to the MCC-free XDI composition, for example, at room temperature (25° C.) and atmospheric pressure (0.1 MPa).

[0102] The amount of hydrogen chloride supplied is, for example, 0.08 mmol or more and, for example, 10 mmol or less, preferably 8.0 mmol or less, more preferably 6.0 mmol or less, per mole of XDI in the MCC-free XDI composition.

[0103] When the amount of hydrogen chloride supplied is below the upper limit, XDI mainly reacts with hydrogen chloride, producing monocarbamoyl Cl isomers almost quantitatively from the supplied hydrogen chloride. DCI and CBI are present in trace amounts relative to XDI. Therefore, it is considered extremely unlikely that the isocyanato groups of DCI and CBI react with hydrogen chloride to produce carbamoyl Cl isomers. Therefore, the content of monocarbamoyl Cl isomers in the XDI composition can be adjusted by adjusting the amount of hydrogen chloride supplied. The content of monocarbamoyl Cl isomers in the XDI composition is measured by the measurement method described above.

[0104] <Effects> The XDI composition described above contains XDI, the monocarbamoyl Cl form represented by the above chemical formula (1), and DCI represented by the above chemical formula (2). Therefore, a resin produced from the XDI composition described above has excellent heat resistance.

[0105] The mass ratio of the monocarbamoyl Cl form to DCI is preferably less than 3000. However, the resin may be produced by molding into a desired shape by a known casting method. In this case, if the mass ratio of the monocarbamoyl Cl form to DCI in the XDI composition is less than 3000, the releasability of the resin from the mold can be improved, and damage to the resin when it is removed from the mold can be suppressed.

[0106] The XDI composition described above is used as a raw material for resins, and is particularly suitable as a raw material for optical materials. In other words, the XDI composition is preferably contained as an isocyanate component in a polymerizable composition for optical materials.

[0107] The polymerizable composition for an optical material contains an isocyanate component and an active hydrogen group-containing component.

[0108] The isocyanate component contains, and preferably consists of, an XDI composition.

[0109] Examples of the active hydrogen group-containing component include a polyol component, a polythiol component, and a polyamine component.

[0110] The active hydrogen group-containing component may be used alone or in combination of two or more kinds.

[0111] Among the active hydrogen group-containing components, polythiol components are preferred from the viewpoint of optical properties, for example.

[0112] Examples of the polythiol component include an aliphatic polythiol compound, an aromatic polythiol compound, and a heterocyclic polythiol compound.

[0113] Examples of aliphatic polythiol compounds include methanedithiol, 1,2-ethanedithiol, 1,2,3-propanetrithiol, 1,2-cyclohexanedithiol, bis(2-mercaptoethyl)ether, tetrakis(mercaptomethyl)methane, diethylene glycol bis(2-mercaptoacetate), diethylene glycol bis(3-mercaptopropionate), ethylene glycol bis(2-mercaptoacetate), ethylene glycol bis(3-mercaptopropionate), trimethylolpropane tris(2-mercaptoacetate), ester), trimethylolpropane tris(3-mercaptopropionate), trimethylolethane tris(2-mercaptoacetate), trimethylolethane tris(3-mercaptopropionate), pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), bis(mercaptomethyl)sulfide, bis(mercaptomethyl)disulfide, bis(mercaptoethyl)sulfide, bis(mercaptoethyl)disulfide, bis(mercaptopropyl)sulfide, Bis(mercaptomethylthio)methane, bis(2-mercaptoethylthio)methane, bis(3-mercaptopropylthio)methane, 1,2-bis(mercaptomethylthio)ethane, 1,2-bis(2-mercaptoethylthio)ethane, 1,2-bis(3-mercaptopropylthio)ethane, 1,2,3-tris(mercaptomethylthio)propane, 1,2,3-tris(2-mercaptoethylthio)propane, 1,2,3-tris(3-mercaptopropylthio)propane, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 5,7 -dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, tetrakis(mercaptomethylthiomethyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, bis(2,3-dimercaptopropyl)sulfide, 2,5-dimercaptomethyl-1,4-dithiane, 2,5-Dimercapto-1,4-dithiane, 2,5-dimercaptomethyl-2,5-dimethyl-1,4-dithiane, and their esters of thioglycolic acid and mercaptopropionic acid, hydroxymethyl sulfide bis(2-mercaptoacetate), hydroxymethyl sulfide bis(3-mercaptopropionate), hydroxyethyl sulfide bis(2-mercaptoacetate), hydroxyethyl sulfide bis(3-mercaptopropionate), hydroxymethyl disulfide bis(2-mercaptoacetate), hydroxymethyl disulfide bis(3-mercaptopropionate), hydroxyethyl disulfide bis(2-mercaptoacetate), hydroxyethyl disulfide bis(3-mercaptopropionate), 2-mercaptoethyl ether bis(2-mercaptoacetate), 2-mercapto Examples of suitable mercaptomethylthioesters include ethyl ether bis(3-mercaptopropionate), thiodiglycolic acid bis(2-mercaptoethyl ester), thiodipropionic acid bis(2-mercaptoethyl ester), dithiodiglycolic acid bis(2-mercaptoethyl ester), dithiodipropionic acid bis(2-mercaptoethyl ester), 1,1,3,3-tetrakis(mercaptomethylthio)propane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, 4,6-bis(mercaptomethylthio)-1,3-dithiane, 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane, 3-mercaptomethyl-1,5-dimercapto-2,4-dithiapentane, tris(mercaptomethylthio)methane, tris(mercaptoethylthio)methane, and 2,5-bis(mercaptomethyl)-1,4-dithiane.

[0114] Examples of aromatic polythiol compounds include 1,2-dimercaptobenzene, 1,3-dimercaptobenzene, 1,4-dimercaptobenzene, 1,2-bis(mercaptomethyl)benzene, 1,3-bis(mercaptomethyl)benzene, 1,4-bis(mercaptomethyl)benzene, 1,2-bis(mercaptoethyl)benzene, 1,3-bis(mercaptoethyl)benzene, 1,4-bis(mercaptoethyl)benzene, 1,3,5-trimercaptobenzene, 1,3,5-tris(mercaptomethyl)benzene, 1,3,5-tris(mercaptomethyleneoxy)benzene, 1,3,5-tris(mercaptoethyleneoxy)benzene, 2,5-toluenedithiol, 3,4-toluenedithiol, 1,5-naphthalenedithiol, and 2,6-naphthalenedithiol.

[0115] Examples of heterocyclic polythiol compounds include 2-methylamino-4,6-dithiol-sym-triazine, 3,4-thiophenedithiol, and bismuthiol.

[0116] Such polythiol components can be used alone or in combination of two or more kinds.

[0117] Furthermore, preferred examples of the polythiol component include 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), 2,5-bis(mercaptomethyl)-1,4-dithiane, bis(mercaptomethyl)-1,4-dithiane, and the like. and at least one selected from the group consisting of 1,2,3-tetrakis(mercaptomethylthio)propane, 4,6-bis(mercaptomethylthio)-1,3-dithiane, 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, 3-mercaptomethyl-1,5-dimercapto-2,4-dithiapentane, tris(mercaptomethylthio)methane, ethylene glycol bis(3-mercaptopropionate), and diethylene glycol bis(3-mercaptopropionate).

[0118] 3. Resin A resin is produced by reacting the above-described isocyanate component with the above-described active hydrogen group-containing component. In other words, the resin is a cured product of the polymerizable composition for optical materials. Therefore, the resin is an optical material. The resin is preferably molded by a known molding method. In other words, the molded product contains the resin. Therefore, the molded product is an optical component. An example of a molded resin product is an optical element.

[0119] Examples of the optical element include a lens, a sheet, and a film, and preferably a lens.

[0120] The lens is produced, for example, by reacting the XDI composition with the polythiol component, and the lens can be produced, for example, by a casting method.

[0121] Examples of lenses include clear lenses, sunglasses lenses, polarized lenses, eyeglass lenses, camera lenses, pickup lenses, and contact lenses.

[0122] <Effects> The resin, molded article, optical element, and lens described above contain a cured product of the polymerizable composition for optical materials described above, and therefore the resin, molded article, optical element, and lens have excellent heat resistance.

[0123] The XDI composition described above can also be used as a raw material for coatings (e.g., paints and adhesives). In this case, the XDI composition is modified as needed by a known method and then incorporated as an isocyanate component into a polymerizable composition for coating.

[0124] The xylylene diisocyanate modified composition (hereinafter referred to as XDI modified composition) is produced by modifying the above-described XDI composition, and contains at least one of the following functional groups (a) to (i): (a) an isocyanurate group, (b) an allophanate group, (c) a biuret group, (d) a urethane group, (e) a urea group, (f) an iminooxadiazinedione group, (g) a uretdione group, (h) a uretonimine group, and (i) a carbodiimide group.

[0125] More specifically, the XDI modified composition containing the functional group (isocyanurate group) described above in (a) contains a trimer of XDI, and can be obtained, for example, by adding a known isocyanuration catalyst to an XDI monomer composition, allowing the composition to react, and thereby isocyanurating (e.g., trimerizing) the XDI.

[0126] The XDI modified composition containing the functional group (allophanate group) of (b) above contains an allophanate modified XDI, and can be obtained, for example, by reacting an XDI monomer composition with a monohydric alcohol or a dihydric alcohol, and then adding a known allophanate catalyst to further react the resulting mixture.

[0127] The XDI modified composition containing the functional group (biuret group) of (c) above contains a biuret modified XDI, and can be obtained, for example, by reacting an XDI monomer composition with water or a secondary amine, and then adding a known biuret catalyst to further react.

[0128] The XDI modified composition containing the functional group (urethane group) of (d) above contains a polyol modified XDI, and can be obtained, for example, by reacting an XDI monomer composition with a low-molecular-weight polyol (e.g., trimethylolpropane).

[0129] The XDI modified composition containing the functional group (urea group) of (e) above contains a polyamine modified XDI, and can be obtained, for example, by reacting an XDI monomer composition with a polyamine.

[0130] The XDI modified composition containing the functional group (f) (iminooxadiazinedione group) contains an iminooxadiazinedione modified product (asymmetric trimer) of XDI, and can be obtained, for example, by reacting the XDI composition in the presence of a known iminooxadiazinedione-forming catalyst to convert XDI into iminooxadiazinedione (e.g., trimerization).

[0131] The XDI modified composition containing the functional group (uretdione group) of (g) above contains a uretdione modified XDI, and can be obtained, for example, by applying heat to the XDI composition at about 90°C to 200°C, or by reacting the XDI in the presence of a known uretdione-forming catalyst to uretdioneize (e.g., dimerize) the XDI.

[0132] The XDI modified composition containing the functional group (uretonimine group) of (h) above contains a uretonimine modified XDI, and can be obtained, for example, by reacting an XDI composition in the presence of a known carbodiimidation catalyst to form a carbodiimide group, and then adding XDI to the carbodiimide group.

[0133] The XDI modified composition containing the functional group (carbodiimide group) described above (i) contains a carbodiimide modified XDI, and can be obtained, for example, by reacting an XDI composition in the presence of a known carbodiimide catalyst.

[0134] The XDI modified composition may contain at least one of the functional groups (a) to (i) above, and may contain two or more of them. The XDI modified composition may be used alone or in combination of two or more thereof.

[0135] The polymerizable composition for coating is, for example, a two-component curable resin raw material, and contains an agent A as a curing agent and an agent B as a main component.

[0136] The component A includes, for example, the above-described XDI modified composition, and the component B includes, for example, a polyol component.

[0137] A coating formed from such a polymerizable coating composition also has excellent heat resistance.

[0138] The present invention will be described in more detail below with reference to examples, but is not limited thereto. Specific numerical values ​​such as blending ratios (content ratios), physical property values, and parameters used in the following description can be replaced with the upper limit values ​​(numeric values ​​defined as "not more than" or "less than") or lower limit values ​​(numeric values ​​defined as "not less than" or "exceeding") of the corresponding blending ratios (content ratios), physical property values, and parameters described in the above "Modes for Carrying Out the Invention." Note that "parts" and "%" are based on mass unless otherwise specified.

[0139] <Measurement Method> The method for measuring the content of the compound (DCI) represented by the above chemical formula (2) and the method for measuring the pot life are as follows.

[0140] <<DCI Content>> DCI with a purity of 99 mol% synthesized in the same manner as in Preparative Example 1 of WO 2018 / 190290 was used as a standard substance and analyzed by gas chromatography under the following conditions. A calibration curve was created from the area values ​​of the obtained gas chromatogram (absolute calibration curve method).

[0141] Next, the XDI composition of each Example described later was analyzed by gas chromatography under the following conditions to obtain the number of moles of DCI. This was converted to mass to calculate the content of DCI in the XDI composition of each Example described later. The retention time of DCI was 16.6 minutes. Apparatus: HP-6890 / 5873 (manufactured by Hewlett-Packard Company) Column: HP-50+, inner diameter 0.25 mm x length 30 m x film thickness 0.25 μm (manufactured by Hewlett-Packard Company) Oven temperature: heated 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) <<Pot life>> 50.8 parts by mass of the XDI composition obtained in each example and 0.01 parts by mass of dimethyltin dichloride as a curing catalyst were mixed and dissolved at 20°C. Subsequently, 49.2 parts by mass of a polythiol component mainly composed 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 were added and mixed to prepare a mixed homogeneous liquid. 10 g of this mixed homogeneous liquid was placed in a sample bottle and stirred with a magnetic stirrer at a temperature of 25°C. Every hour, the stirring state was visually confirmed, and the time until the viscosity of the mixed homogeneous liquid increased and stirring with a magnetic stirrer became impossible was measured. The longer this time, the better the pot life was determined to be.

[0142] <Preparation Example: Preparation of XDI composition substantially free of monocarbamoyl Cl forms (MCC-free XDI composition)> <<Preparation Example 1>> An MCC-free XDI composition was produced in accordance with the method described in WO 2018 / 190290.

[0143] Specifically, 457.5 parts by mass of orthodichlorobenzene (ODCB) and 43 parts by mass of m-XDA (total amine concentration 9% by mass) were charged into a stirring vessel. The temperature was then raised to 120°C, and hydrogen chloride gas was then blown into the ODCB and XDA mixture at a rate of 23 parts by mass / hr for 2 hours. This yielded a slurry containing XDA hydrochloride.

[0144] Next, the slurry (XDA hydrochloride) was continuously transferred from the stirring tank to a reaction tank separate from the stirring tank, and carbonyl chloride was supplied to the XDA hydrochloride in the reaction tank to cause a reaction, while the reaction mass was continuously removed from the reaction tank.

[0145] The reaction temperature of the XDA hydrochloride and the carbonyl chloride was 150° C., and the reaction pressure (gauge pressure) of the XDA hydrochloride and the carbonyl chloride was 0.03 MPa G. The supply ratio of carbonyl chloride to 1 mole of XDA hydrochloride was 12 moles.

[0146] The reaction mass was then degassed and desolvated to further remove tar components.

[0147] Thereafter, the reaction mass from which the tar components had been removed was distilled in a low boiling point removal tower under the following conditions to remove low boiling points. The low boiling point removal tower was packed with packing equivalent to 10 theoretical plates.

[0148] Low boiling point removal conditions in the low boiling point removal tower: Tower bottom temperature: 160 to 170°C Tower top temperature: 115 to 125°C Tower top pressure: 0.5 to 1.0 kPa Tower top reflux amount: 100 parts / hr Low boiling point distillate amount: 3.1 parts / hr Tower top reflux ratio: 32 Residence time: 0.3 to 3 hr Next, the reaction mass from which the low boiling points had been removed was rectified in a rectification tower under the following conditions to obtain an XDI composition as a fraction. The rectification tower was packed with packing equivalent to a theoretical plate number of 3.

[0149] Rectification conditions in the rectification column: Column bottom temperature: 150 to 160°C Column top temperature: 140 to 150°C Column top pressure: 0.5 to 0.8 kPa Distillate amount of XDI composition: 93.7 parts / hr Column top reflux ratio: 1 Residence time: 1 to 10 hr In this manner, an XDI composition containing no MCC bodies was produced.

[0150] <<Preparation Example 2>> An XDI composition containing no MCC bodies was produced in the same manner as in Preparation Example 1. In Preparation Example 2, the reaction pressure (gauge pressure) between XDA hydrochloride and carbonyl chloride was changed to 0.044 MPaG, and the supply ratio of carbonyl chloride per mole of XDA hydrochloride was changed to 13.0 moles. In addition, the distillation rate of low boilers in the low boiler removal tower was changed to 3.4 parts / hr, and the tower top reflux ratio was changed to 29. Furthermore, the distillation rate of the XDI composition in the rectification tower was changed to 93.8 parts / hr.

[0151] <<Preparation Example 3>> An XDI composition containing no MCC isomers was produced in the same manner as in Preparation Example 2. In Preparation Example 3, the reaction pressure (gauge pressure) between XDA hydrochloride and carbonyl chloride was changed to 0.07 MPaG, and the supply ratio of carbonyl chloride per mole of XDA hydrochloride was changed to 15.2 moles.

[0152] Examples 1 to 24: Preparation of XDI compositions Hydrogen chloride gas was blown into the MCC-isomer-free XDI compositions obtained in each preparation example immediately after rectification so that the content of monocarbamoyl Cl isomer in the XDI composition reached the target value.

[0153] The content of the monocarbamoyl Cl form in the obtained XDI composition was measured by the above-mentioned measurement method. The results are shown in Table 1.

[0154] The content of DCI in each XDI composition was measured according to the above-mentioned measurement method. The results are shown in Table 1. The mass ratio of the monocarbamoyl Cl form to DCI is also shown in Table 1. The pot life when each XDI composition was mixed with a polythiol component was also measured according to the above-mentioned measurement method. The results are shown in Table 1. The pot life of the polymerizable composition for optical materials was also measured according to the following measurement method. The results are shown in Table 2. The molar ratio of the catalyst to the monocarbamoyl Cl form is also shown in Table 2. <<Pot Life>> A curing catalyst shown in Table 2 was mixed and dissolved in 50.8 parts by mass of the XDI composition of Example 1 at 20°C in the blending amount shown in Table 2. Subsequently, 49.2 parts by mass of a polythiol component mainly composed 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 was added and mixed to obtain the polymerizable compositions for optical materials of Examples 25 to 27 and Comparative Examples 1 to 4 as mixed homogeneous liquids. The obtained polymerizable compositions for optical materials were placed in sample bottles and stirred with a magnetic stirrer at a temperature of 20°C. Every hour, the viscosity (mPa s) of the polymerizable compositions for optical materials at 20°C was measured using a Brookfield B-type viscometer. The time when the viscosity (mPa·s) at 20°C exceeds 40 mPa·s is defined as time (A), and the time when the viscosity (mPa·s) at 20°C exceeds 1000 mPa·s is defined as time (B).

[0155] <Production of Plastic Lenses> 50.2 parts by mass of the XDI composition obtained in each Example, 0.01 part by mass of dimethyltin dichloride as a curing catalyst, 0.10 part by mass of Zelec UN (trade name, product of Stepan Corporation; acidic phosphate ester), and 1.5 parts by mass of Biosorb 583 (product of Kyodo Pharmaceutical Co., Ltd.; ultraviolet absorber) were mixed and dissolved at 20° C. Then, 49.2 parts by mass of a polythiol composition mainly composed 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 was added to the mixture and mixed to prepare a homogeneous solution.

[0156] This homogeneous liquid was degassed at 600 Pa for 1 hour, filtered through a 1 μm Teflon (registered trademark) filter, and then poured into a mold consisting of a glass mold and tape. This mold was placed in an oven, and the temperature was gradually raised from 25°C to 120°C, and polymerization was carried out for 24 hours. After polymerization was completed, the mold was removed from the oven and demolded to obtain a resin (plastic lens). The resin had a disk shape with a thickness of 9 mm and a diameter of 75 mm.

[0157] The mold releasability of the resin was evaluated according to the following criteria. The results are shown in Table 1. A: When the resin was released from the glass mold, it was possible to release it without damage to either the glass mold or the resin. B: When the resin was released from the glass mold, the glass mold was not damaged, but the resin was damaged. C: After heat polymerization and cooling, the glass mold was already damaged when the resin was released from the glass mold.

[0158] The resulting resin was then further annealed at 120° C. for 1 hour to produce a plastic lens.

[0159] The glass transition temperature Tg of the obtained plastic lens was then measured using a Shimadzu TMA-60 thermomechanical analyzer by the TMA penetration method (50 g load, pin tip 0.5 mmφ, heating rate 10°C / min) to serve as an index of heat resistance. The results are shown in Table 1. The correlation between the mass ratio of monocarbamoyl Cl-form to DCI in the XDI composition of each Example and the glass transition temperature (Tg) of the resin (plastic lens) is shown in Figure 1. The correlation between the content of monocarbamoyl Cl-form in the XDI composition of each Example and the glass transition temperature (Tg) of the resin (plastic lens) is shown in Figure 2.

[0160] From the results shown in Table 2, the time (A) of Comparative Example 1 is longer than the time (B) of Examples 25 and 26. Therefore, it can be determined that the polymerizable composition for optical materials of Comparative Example 1 is more difficult to thermally cure than the polymerizable compositions for optical materials of Examples 25 and 26. The time (A) of Comparative Example 2 is longer than the time (B) of Examples 27, 28, and 29. Therefore, it can be determined that the polymerizable composition for optical materials of Comparative Example 2 is more difficult to thermally cure than the polymerizable compositions for optical materials of Examples 27, 28, and 29.

Claims

1. A xylylene diisocyanate composition comprising: xylylene diisocyanate; a compound represented by the following chemical formula (1); and a compound represented by the following chemical formula (2).

2. The xylylene diisocyanate composition according to claim 1, wherein the mass ratio of the compound represented by chemical formula (1) to the compound represented by chemical formula (2) is 10,000 or less.

3. The xylylene diisocyanate composition according to claim 2, wherein the mass ratio of the compound represented by chemical formula (1) to the compound represented by chemical formula (2) is less than 3,000.

4. The xylylene diisocyanate composition according to any one of claims 1 to 3, further comprising a curing catalyst represented by the following chemical formula (3), wherein the molar ratio of the curing catalyst to the compound represented by the chemical formula (1) is 2 or more: (In chemical formula (3), R １ represents a linear alkyl group having 1 to 20 carbon atoms, a branched alkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or a halogen atom. m is an integer of 0 to 5. When m is 2 to 5, multiple R １ may be the same or different. Q represents a carbon atom or a nitrogen atom.

5. The xylylene diisocyanate composition according to claim 4, wherein the curing catalyst is at least one selected from the group consisting of pyridine, 3-chloropyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 3-ethylpyridine, 2,6-dimethylpyridine, 3,5-dimethylpyridine, 2,4,6-trimethylpyridine, and 2-methylpyrazine.

6. A polymerizable composition for optical materials, comprising the xylylene diisocyanate composition according to any one of claims 1 to 5 and an active hydrogen group-containing component.

7. The active hydrogen-containing component is selected from the group consisting of 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), 2,5-bis(mercaptomethyl)-1,4-dithiane, bis(mercaptomethyl)-1,4-dithiane, 7. The polymerizable composition for an optical material according to claim 6, comprising at least one polythiol selected from the group consisting of 1,2,3-tetrakis(mercaptomethylthio)methyl sulfide, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 4,6-bis(mercaptomethylthio)-1,3-dithiane, 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, 3-mercaptomethyl-1,5-dimercapto-2,4-dithiapentane, tris(mercaptomethylthio)methane, and ethylene glycol bis(3-mercaptopropionate).

8. A resin which is a cured product of the polymerizable composition for optical materials according to claim 6 or 7.

9. A molded article comprising the resin according to claim 8.

10. An optical element comprising the molded article according to claim 9.

11. A lens comprising the optical element of claim 10.