KR20220024347A - Method of preparing diisocyanate composition and optical lens - Google Patents

Abstract

An embodiment relates to a process of preparing diisocyanate from diamine through diamine hydrochloride in which an aqueous hydrochloric acid solution can be used instead of hydrogen chloride gas and solid triphosgene can be used instead of phosgene gas. In addition, the embodiment provides a preparation method of a diisocyanate composition and an optical lens which has excellent yield and quality while reducing an environmental problem by controlling the total content of cations in the diisocyanate composition within a specific range.

Description

Diisocyanate composition and manufacturing method of an optical lens {METHOD OF PREPARING DIISOCYANATE COMPOSITION AND OPTICAL LENS}

Embodiments relate to diisocyanate compositions and methods of making optical lenses. More specifically, the embodiment relates to a method for preparing a diisocyanate composition using a diamine hydrochloride composition, and a method for manufacturing an optical lens using the diisocyanate composition.

Isocyanate used as a raw material for plastic optical lenses is manufactured by a phosgene method, a non-phosgene method, a thermal decomposition method, or the like.

The phosgene method is to react a raw material amine with phosgene (COCl ₂ ) gas to synthesize isocyanate, and the biphosgene method is to react xylylene chloride with sodium cyanate in the presence of a catalyst to synthesize isocyanate, and the thermal decomposition method is to synthesize an amine After reacting with alkyl chloroformate to prepare carbamate, it is pyrolyzed at high temperature in the presence of a catalyst to synthesize isocyanate.

Among these isocyanate manufacturing methods, the phosgene method is most widely used, and in particular, a direct method of directly reacting phosgene gas with an amine has been generally used, but there is a problem that requires a large number of devices for the direct reaction of the phosgene gas. Meanwhile, in order to supplement the direct method, as in Korean Patent Publication No. 1994-0001948, a hydrochloride method was developed in which an amine hydrochloride was obtained by reacting an amine with hydrogen chloride gas and reacted with phosgene.

In the conventional phosgene method for synthesizing isocyanate, the method of reacting an amine with hydrogen chloride gas to obtain a hydrochloride as an intermediate material, the hydrochloride is generated as fine particles at normal pressure, and the stirring condition inside the reactor is not smooth, so the pressure inside the reactor In order to increase the temperature, an additional process of increasing the temperature is required, and there is a problem in that the yield of the final product is also low.

In addition, the phosgene gas used in the conventional phosgene method is a substance subject to environmental regulations as it is highly toxic, and there is a problem in storage and management, such as a separate cooling device is required to store it.

(Patent Document 1) Korean Patent Publication No. 1994-0001948

Therefore, in the process of manufacturing diisocyanate, which is mainly used as a raw material for plastic optical lenses, from diamine through hydrochloric acid, the present inventors use an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas by adjusting the reaction conditions. , could solve the conventional environmental, yield and quality problems.

In addition, the present inventors can control the total content of cations in the diisocyanate composition by adjusting the amount of the organic solvent added to the reaction in the process of preparing the diamine hydrochloride composition used as a raw material for diisocyanate synthesis, or washing with a specific solvent. It was noted that there is In particular, the present inventors have discovered that when the total content of cations in the diisocyanate composition is out of a specific range, side reactions caused by the cations remaining in the diisocyanate composition are promoted, thereby causing deterioration of physical properties such as streak in the final optical lens. .

Accordingly, an object of the embodiment is to provide a diisocyanate composition capable of improving optical properties and a method of manufacturing an optical lens by controlling the total content of cations in the diisocyanate composition.

According to an embodiment, (1) reacting a diamine composition with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; and (2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition, wherein before step (2), the diamine hydrochloride composition is dissolved in a solvent having a polarity of 6.2 to 9.8 and recrystallized Further comprising the step of, the total content of cations in the diisocyanate composition is controlled to 100 ppm or less, a method for producing a diisocyanate composition is provided.

According to another embodiment, (1) reacting a diamine composition with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; (2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition; and (3) mixing the diisocyanate composition with thiol or episulfide and polymerizing and curing in a mold, prior to step (2), the diamine hydrochloride composition is dissolved in a solvent having a polarity of 6.2 to 9.8. Further comprising the step of recrystallization after dissolution, the total content of cations in the diisocyanate composition is controlled to 100 ppm or less, a method of manufacturing an optical lens is provided.

The manufacturing method of diisocyanate according to the above embodiment uses triphosgene with low toxicity without requiring a separate cooling storage device as a solid state at room temperature without using phosgene gas, which is difficult to store and manage and highly toxic. Therefore, it has excellent handling and fairness. In addition, the method for producing diisocyanate according to the embodiment uses an aqueous hydrochloric acid solution without using hydrogen chloride gas for the production of diamine hydrochloride, which is an intermediate material, so that the reaction can proceed even at normal pressure, so an additional device for high-temperature heating and cooling is required and the yield can also be improved.

In addition, in the method for producing a diisocyanate composition according to the embodiment, the final yield can be further increased by preparing a diamine hydrochloride composition using an aqueous hydrochloric acid solution, and the range of raw material selection is not greatly affected by the moisture and impurity content in the raw material diamine. can be widened

In particular, according to the above embodiment, by controlling the total content of cations in the diisocyanate within a specific range, side reactions caused by the cations remaining in the diisocyanate composition are suppressed, and deterioration of physical properties such as occurrence of streaks in the final optical lens can be prevented.

Therefore, the method for preparing the diisocyanate composition according to the embodiment can be applied to the manufacture of high-quality plastic optical lenses.

1 schematically shows a method for preparing a diisocyanate composition according to an embodiment.
2 shows an example of a process device for the reaction of diamine hydrochloride and triphosgene.

In the present specification, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.

In addition, it should be understood that all numerical ranges indicating physical property values, contents, dimensions, etc. of the components described in the present specification are modified by the term "about" in all cases unless otherwise specified.

As used herein, "amine" means a compound having at least one amine group at the terminal, "diamine" means a compound having two amine groups at the terminal, and an aliphatic chain, an aliphatic ring, and an aromatic ring It may have a very diverse structure depending on the skeleton. Specific examples of the diamine include xylylenediamine (XDA), hexamethylenediamine (HDA), 2,2-dimethylpentanediamine, 2,2,4-trimethylhexanediamine, butenediamine, 1,3-butadiene-1, 4-diamine, 2,4,4-trimethylhexamethylenediamine, bis(aminoethyl)carbonate, 4,4'-methylenediamine (MDA), bis(aminoethyl)ether, bis(aminoethyl)benzene, bis(amino Propyl)benzene, α,α,α',α'-tetramethylxylylenediamine, bis(aminobutyl)benzene, bis(aminomethyl)naphthalene, bis(aminomethyl)diphenyl ether, bis(aminoethyl)phthalate , 2,6-di(aminomethyl)furan, xylylenediamine hydride (H6XDA), dicyclohexylmethanediamine, cyclohexanediamine, methylcyclohexanediamine, isophoronediamine (IPDA), dicyclohexyldimethylmethanediamine, 2 ,2-Dimethyldicyclohexylmethanediamine, 2,5-bis(aminomethyl)bicyclo-[2,2,1]-heptane, 2,6-bis(aminomethyl)bicyclo-[2,2,1 ]-Heptane, 3,8-bis(aminomethyl)tricyclodecane, 3,9-bis(aminomethyl)tricyclodecane, 4,8-bis(aminomethyl)tricyclodecane, 4,9-bis(amino Methyl) tricyclodecane, norbornenediamine (NBDA), bis (aminomethyl) sulfide, bis (aminoethyl) sulfide, bis (aminopropyl) sulfide, bis (aminohexyl) sulfide, bis (aminomethyl) Sulfone, bis(aminomethyl)disulfide, bis(aminoethyl)disulfide, bis(aminopropyl)disulfide, bis(aminomethylthio)methane, bis(aminoethylthio)methane, bis(aminoethylthio)ethane, Bis(aminomethylthio)ethane etc. are mentioned. More specifically, the diamine is one selected from the group consisting of xylylenediamine (XDA), norbornenediamine (NBDA), hydrogenated xylylenediamine (H6XDA), isophoronediamine (IPDA) and hexamethylenediamine (HDA) may be more than The xylylenediamine (XDA) includes orthoxylylenediamine (o-XDA), metaxylylenediamine (m-XDA), and paraxylylenediamine (p-XDA).

As used herein, "isocyanate" means a compound having an NCO group, "diisocyanate" means a compound having two NCO groups at the terminal, and depending on the skeleton of an aliphatic chain, an aliphatic ring, and an aromatic ring It can have a wide variety of structures. Specific examples of the diisocyanate include xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), 2,5-bis(isocyanatomethyl)-bicyclo[2.2.1]heptane, 2,6-bis (isocyanatomethyl)-bicyclo[2.2.1]heptane, xylylene hydride diisocyanate (H6XDI), dicyclohexylmethane diisocyanate, isophorone diisocyanate (IPDI), 1,2-diisocyanatobenzene , 1,3-diisocyanatobenzene, 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene, ethylphenylene diisocyanate, dimethylphenylene diisocyanate, biphenyl diisocyanate, toluidine diisocyanate, 4,4'-methylenebis(phenylisocyanate)(MDI), 1,2-bis(isocyanatomethyl)benzene, 1,3-bis(isocyanatomethyl)benzene, 1,4-bis(iso Cyanatomethyl)benzene, 1,2-bis(isocyanatoethyl)benzene, 1,3-bis(isocyanatoethyl)benzene, 1,4-bis(isocyanatoethyl)benzene, α ,α,α',α'-tetramethylxylylenediisocyanate, bis(isocyanatomethyl)naphthalene, bis(isocyanatomethylphenyl)ether, norbornene diisocyanate (NBDI), bis(isocyanatomethyl) ) sulfide, bis (isocyanatoethyl) sulfide, bis (isocyanatopropyl) sulfide, 2,5-diisocyanatotetrahydrothiophene, 2,5-diisocyanatomethyltetrahydro Thiophene, 3,4-diisocyanatomethyltetrahydrothiophene, 2,5-diisocyanato-1,4-dithiane, 2,5-diisocyanatomethyl-1,4-dithiane, etc. can be heard More specifically, the diisocyanate is xylylene diisocyanate (XDI), norbornene diisocyanate (NBDI), hydrogenated xylylene diisocyanate (H6XDI), isophorone diisocyanate (IPDI) and the group consisting of hexamethylene diisocyanate (HDI) It may be one or more selected from. The xylylene diisocyanate (XDI) includes ortho-xylylene diisocyanate (o-XDI), meta-xylylene diisocyanate (m-XDI) and para-xylylene diisocyanate (p-XDI).

As used herein, the term “composition” may refer to a form in which two or more chemical components are mixed or combined in a solid, liquid and/or gaseous phase while generally maintaining their respective unique properties.

In the present specification, the ppm unit means ppm based on weight.

A compound (eg, triphosgene) or a compound obtained as a result of the reaction (eg, diamine hydrochloride, diisocyanate) used in each reaction step according to the embodiment is generally a residual, side reaction, or moisture of an unreacted sample in each reaction step. It exists in a mixed or combined state with heterogeneous components generated due to a reaction with or natural decomposition of a compound, and these heterogeneous components may be present together with the main component in a trace amount even after several purifications.

According to the above embodiment, since attention is paid to these heterogeneous components mixed or combined with the main compound, even a trace amount of the heterogeneous component is treated as a composition in a state mixed or combined with the main compound, and the components and contents thereof are specifically exemplified.

In addition, in this specification, for clear and easy distinction between various compositions, terms are also described in combination with the name of the main component in the composition, for example, "diamine hydrochloride composition" means a composition containing diamine hydrochloride as a main component, , "diisocyanate composition" means a composition comprising diisocyanate as a main component. At this time, the content of the main component in the composition may be 50% by weight or more, 80% by weight or more, or 90% by weight or more, for example, may be 90% by weight to 99.9% by weight.

[Method for producing diisocyanate composition]

According to an embodiment, (1) reacting a diamine composition with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; and (2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition, wherein before step (2), the diamine hydrochloride composition is dissolved in a solvent having a polarity of 6.2 to 9.8 and recrystallized Further comprising the step of, the total content of cations in the diisocyanate composition is controlled to 100 ppm or less, a method for producing a diisocyanate composition is provided.

1 schematically shows a method for preparing a diisocyanate composition according to an embodiment. In FIG. 1, R includes an aromatic ring, an aliphatic ring, an aliphatic chain, and the like, and as a specific example, R may be xylylene, norbornene, xylylene hydride, isophorone, or hexamethylene, but is not limited thereto.

Hereinafter, each step will be described in detail.

Preparation of diamine hydrochloride composition

First, diamine is reacted with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition.

In addition, after the reaction of the diamine composition with the aqueous hydrochloric acid solution, a first organic solvent may be additionally added to obtain the diamine hydrochloride composition in a solid phase.

Scheme 1 below shows an example of the reaction of this step.

[Scheme 1]

In the above formula, R includes an aromatic ring, an aliphatic ring, an aliphatic chain, and the like, and as a specific example, R may be xylylene, norbornene, xylylene hydride, isophorone or hexamethylene, but is not limited thereto.

In the case of using hydrogen chloride gas in the prior art, since hydrochloride is generated as fine particles during the atmospheric reaction and the stirring state inside the reactor is not smooth, a process of increasing the internal temperature of the reactor by increasing the pressure is additionally required, and the final process product There was also a problem with the yield of low.

However, according to the above embodiment, since the aqueous hydrochloric acid solution is used, it is possible to solve the problem that occurs when using hydrogen chloride gas in the prior art. Specifically, when an aqueous hydrochloric acid solution is used, the yield is high because the product produced through the reaction is in the form of a solid rather than in the form of a slurry, and a separate device or process for rapid cooling is not required because the reaction can be carried out even at atmospheric pressure.

The concentration of the aqueous hydrochloric acid solution may be 5 wt% to 50 wt%. When it is within the above concentration range, it is possible to minimize the dissolution of hydrochloric acid in the aqueous hydrochloric acid solution, thereby increasing the final yield and improving handling.

Specifically, the concentration of the aqueous hydrochloric acid solution may be 10 wt% to 45 wt%, 20 wt% to 45 wt%, or 30 wt% to 40 wt%. More specifically, the aqueous hydrochloric acid solution may have a concentration of 20 wt% to 45 wt%.

The diamine and the aqueous hydrochloric acid solution may be added to the reaction in an equivalent ratio of 1: 2 to 5. When the equivalence ratio is within the range, it is possible to prevent the yield from being lowered due to dissolution due to the generation of moisture while reducing unreacted substances. Specifically, the diamine and the aqueous hydrochloric acid solution may be added to the reaction in an equivalent ratio of 1: 2 to 2.5.

The diamine and the aqueous hydrochloric acid solution may be added while maintaining a constant temperature inside the reactor. The temperature inside the reactor when the diamine and the aqueous hydrochloric acid solution are added may be in a range of 20°C to 100°C. When it is within the above temperature range, it is possible to prevent the temperature from being higher than the boiling point, which is not suitable for the reaction, or the reaction efficiency is decreased due to the temperature being too low. Specifically, the temperature inside the reactor when the diamine and the aqueous hydrochloric acid solution are added may be 20°C to 60°C, more specifically 20°C to 40°C, or 40°C to 60°C.

In the conventional hydrochloric acid salt method, a lot of heat is generated during the reaction process and thus rapid cooling is required through a separate cooler, whereas according to the above embodiment, a separate cooler is not required because the reactant is introduced while maintaining a low temperature.

The diamine and the aqueous hydrochloric acid solution may be added, for example, in the order of first introducing the hydrochloric acid aqueous solution into the reactor and then slowly introducing the diamine. The diamine and/or the aqueous hydrochloric acid solution may be added for 30 minutes to 3 hours.

After the addition of the diamine and the aqueous hydrochloric acid solution is completed, the temperature inside the reactor may be cooled to 0°C to 20°C, 0°C to 10°C, or 10°C to 20°C.

The reaction of the diamine and the aqueous hydrochloric acid solution may be carried out at normal pressure, for example, may be performed while stirring for 30 minutes to 2 hours.

Through the reaction of the diamine with the aqueous hydrochloric acid solution, a reaction result in an aqueous solution state in which the diamine hydrochloride composition is dissolved in water may be obtained.

Thereafter, the step of treating the diamine hydrochloride composition may be further performed. For example, treating the diamine hydrochloride composition includes precipitating the diamine hydrochloride composition, filtering the diamine hydrochloride composition, drying the diamine hydrochloride composition, and washing the diamine hydrochloride composition, It may include at least one.

Specifically, the solid diamine hydrochloride composition may be precipitated by adding the first organic solvent to the reaction product. That is, the first organic solvent may induce precipitation of the solid diamine hydrochloride composition through crystallization. More specifically, the first organic solvent may be added to the reaction result, and after cooling, the reaction may proceed while further stirring.

The first organic solvent is specifically diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, methanol, ethanol, dimethyl sulfoxide, dimethyl formamide, acetonitrile, acetone, trichloroethylene, tetrachloroethane, It may be at least one selected from the group consisting of trichloroethane, n-butanol, isobutanol, methyl ethyl ketone, methyl butyl ketone, isopropanol, hexane, chloroform and methyl acetate.

The input amount (weight) of the first organic solvent may be 1 to 5 times the weight of the diamine. When it is within the above dosage range, it is possible to prevent the use of excessive organic solvent while the yield of the final hydrochloride is high. Specifically, the first organic solvent may be added to the reaction in an amount of 1 to 2 times, or 1 to 1.5 times the weight of the diamine.

The cooling temperature after the input of the first organic solvent may be -10 °C to 10 °C or -5 °C to 5 °C. In addition, the additional reaction time after the cooling may be 30 minutes to 2 hours, or 30 minutes to 1 hour.

According to a specific example, (1a) adding the aqueous hydrochloric acid solution to the first reactor; (1b) adding and stirring the diamine to the first reactor; and (1c) adding and stirring the first organic solvent to the first reactor may be sequentially performed.

More specifically, cooling the inside of the reactor to a temperature of 0° C. to 10° C. before stirring after the addition of the diamine in step (1b); and cooling the inside of the reactor to a temperature of -5°C to 5°C after the input of the first organic solvent in step (1c) and before stirring.

After the input of the first organic solvent, separation, filtration, washing and drying may be further performed. For example, a solid diamine hydrochloride composition may be obtained by separating the aqueous layer after the input of the first organic solvent, filtration, washing, and drying. The washing may be performed one or more times using, for example, a solvent having a polarity of 5.7 or less. In addition, the drying may use vacuum drying, for example, may be performed at a temperature of 40 ℃ to 90 ℃ and a pressure of 2.0 torr or less.

As a result, impurities generated in the step of obtaining the diamine hydrochloride composition may be removed together with the first organic solvent. Accordingly, the method may further include removing impurities generated in the step of obtaining the diamine hydrochloride composition together with the first organic solvent. Impurities are generated in the reaction process for preparing the diamine hydrochloride composition and are included in the first organic solvent, and the purity of the product can be increased by removing such impurities through the removing step of the first organic solvent.

According to the method, the diamine is reacted with an aqueous hydrochloric acid solution, and the solid diamine hydrochloride composition can be obtained with high purity through additional treatment such as precipitation, filtration, drying, and washing. On the other hand, when diamine is reacted with hydrogen chloride gas in an organic solvent as in the prior art, a slurry of diamine hydrochloride is obtained, which is not easy to purify.

The yield of the diamine hydrochloride composition thus obtained may be 50% or more, 65% or more, 80% or more, 85% or more, or 90% or more, and specifically 85% to 95%, or 88% to 92%. .

Meanwhile, the organic layer may be separated from the reactants and reused as an organic solvent. Accordingly, the recovery rate of the first organic solvent may be 80% or more, 85% or more, or 90% or more, and specifically, 80% to 95%, or 80% to 82%.

Diamine hydrochloride composition

The total content of cations in the diamine hydrochloride composition prepared according to the above embodiment is adjusted to 100 ppm or less. When the cation content in the diamine hydrochloride composition is within the above range, side reactions caused by the cations remaining in the diisocyanate composition prepared therefrom are suppressed, thereby preventing deterioration of physical properties such as streak in the final optical lens. For example, the total content of cations in the diamine hydrochloride composition may be 50 ppm or less, 30 ppm or less, or 20 ppm or less. In addition, the total content of cations in the diamine hydrochloride composition may be 0 ppm or more, 1 ppm or more, 5 ppm or more, or 10 ppm or more.

The total content of cations in the diamine hydrochloride composition may be adjusted in advance before being added to a subsequent reaction.

Accordingly, before being added to the subsequent reaction, the step of measuring the total content of cations in the diamine hydrochloride composition may be further included.

As a result of the measurement, when the total content of cations in the diamine hydrochloride composition is within 100 ppm, it may be directly added to the subsequent reaction.

However, when the total content of cations in the diamine hydrochloride composition exceeds 100 ppm, the total content of cations may be adjusted.

The method of controlling the cation content in the diamine hydrochloride composition may be performed by controlling the reaction conditions for the preparation of the diamine hydrochloride composition to have a specific cation content, or by washing or recrystallizing the diamine hydrochloride composition with a specific solvent. .

The cation in the diamine hydrochloride composition may include a metal ion. For example, the cation in the diamine hydrochloride composition may include an ion of one or more metals selected from the group consisting of Fe, Na, Ca, Mg, Cr, Mn, Ni, Cu, and Zn. Specifically, the diamine hydrochloride composition may include Fe ions, and the content of Fe ions based on the total weight of the diamine hydrochloride composition may be 10 ppm or less.

First, a first organic solvent is added after the reaction between the diamine and the aqueous hydrochloric acid solution described above, and at this time, the amount of the first organic solvent is adjusted to obtain a diamine hydrochloride composition having a specific cation content. For example, the input weight of the first organic solvent may be 1.1 times or more, 1.2 times or more, or 1.3 times or more, and may be 1.9 times or less, 1.7 times or less, or 1.5 times or less compared to the weight of the aqueous hydrochloric acid solution. Specifically, the first organic solvent may be added to the reaction in an amount of 1.3 to 1.5 times the weight of the aqueous hydrochloric acid solution. When it is within the above range, it may be more advantageous to control the cation content in the diamine hydrochloride composition.

In this case, the first organic solvent may include an amphiphilic organic solvent, and specifically, the first organic solvent is diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, methanol, ethanol, dimethyl sulfoxide, At least one selected from the group consisting of dimethylformamide, acetonitrile, acetone, trichloroethylene, tetrachloroethane, trichloroethane, n-butanol, isobutanol, methyl ethyl ketone, methyl butyl ketone, isopropanol and methyl acetate can Effective cation removal can be achieved when using the amphiphilic organic solvent as described above.

Next, the diamine hydrochloride composition can be washed with a specific solvent to control the cation content. That is, before step (2), the step of washing the diamine hydrochloride composition with a solvent having a polarity of 3.9 to 5.7 may be additionally performed. In this case, the solvent used may include, for example, at least one selected from the group consisting of tetrahydrofuran (THF), ethyl acetate, methyl acetate, methyl ethyl ketone, and acetone.

Alternatively, before the step (2), the step of recrystallizing the diamine hydrochloride composition after dissolving it in a solvent having a polarity of 6.2 to 9.8 may be additionally performed. The solvent used at this time may be, for example, water (deionized water), dimethylformamide, dimethyl sulfoxide, or the like. In addition, in the recrystallization, an amphiphilic organic solvent and an aqueous hydrochloric acid solution having a concentration of 20 wt% to 45 wt% may be used together. In this case, the aqueous hydrochloric acid solution used may serve to supplement the amount of hydrochloric acid reduced in the recrystallization process.

In addition, the total content of anions in the diamine hydrochloride composition prepared according to the above embodiment may be adjusted to 100 ppm or less. When the anion content in the diamine hydrochloride composition is within the above range, side reactions caused by the anions remaining in the diisocyanate composition prepared therefrom are suppressed, thereby preventing deterioration of physical properties such as streak in the final optical lens. For example, the total content of anions in the diamine hydrochloride composition may be 100 ppm or less, 900 ppm or less, 60 ppm or less, or 50 ppm or less. In addition, the total content of anions in the diamine hydrochloride composition may be 0 ppm or more, 1 ppm or more, 5 ppm or more, 10 ppm or more, or 15 ppm or more.

Anions in the diamine hydrochloride composition may include non-metal ions. For example, the anion in the diamine hydrochloride composition may be at least one selected from the group consisting of Cl ^- , NO ³ - , SO ₄ ² - , F ^- , Br ^- , NO ² - and PO ⁴ -. Specifically, the diamine hydrochloride composition may include SO ₄ ^2- ions, and the content of SO ₄ ^2- based on the total weight of the diamine hydrochloride composition may be 1030 ppm or less.

In addition, in the manufacturing process of the diamine hydrochloride, the b* value according to the CIE color coordinate of the diamine hydrochloride composition may be increased by being easily changed due to temperature and humidity due to the high reactivity and pH of the diamine. In particular, when preparing a diisocyanate composition using a diamine hydrochloride composition having a b* value of a certain level or higher, color and haze are reduced, and may also affect the striatum, transmittance, yellowness and refractive index of the final optical lens. In addition, when distillation is performed several times to change the discolored diisocyanate composition to be colorless and transparent, it may cause economical degradation due to yield loss.

However, according to the above embodiment, by adjusting the b* value according to the CIE color coordinate in water of the diamine hydrochloride composition, the optical properties of the diisocyanate composition and the optical lens can be improved.

Accordingly, the diamine hydrochloride composition prepared by the method according to the embodiment may have a b* value of 1.2 or less according to the CIE color coordinate when dissolved in water at a concentration of 8% by weight. For example, the b* value according to the CIE color coordinate may be 1.0 or less or 0.8 or less. Specifically, the b* value according to the CIE color coordinate may be 0.1 to 1.2, 0.1 to 1.0, 0.1 to 0.8, or 0.2 to 1.0.

In order to control the b* value of the diamine hydrochloride composition, an aqueous hydrochloric acid solution having an Fe ion content below a certain level may be used as a raw material. For example, the Fe ion content in the aqueous hydrochloric acid solution used for preparing the diamine hydrochloride composition may be 0.5 ppm or less. Specifically, the Fe ion content in the aqueous hydrochloric acid solution may be 0.3 ppm or less, or 0.2 ppm or less. More specifically, the Fe ion content in the aqueous hydrochloric acid solution may be 0.001 ppm to 0.5 ppm, or 0.1 ppm to 0.3 ppm.

Alternatively, the b* value according to the CIE color coordinate of the diamine hydrochloride composition may be adjusted by washing with a solvent having a polarity of 5.7 or less. That is, in the method for preparing the diamine hydrochloride composition used in the above embodiment, the composition containing the diamine hydrochloride is washed with a solvent having a polarity of 5.7 or less, and when dissolved in water at a concentration of 8% by weight, b* value according to the CIE color coordinates It may include the step of adjusting so that it is less than or equal to 1.2.

In this case, the solvent having a polarity of 5.7 or less may include dichloromethane, and other solvents are also possible. In addition, the temperature of the solvent having a polarity of 5.7 or less may be 0 °C to 5 °C.

The diamine hydrochloride composition obtained through the above process mainly includes diamine hydrochloride, and the content of the diamine hydrochloride salt may be 50 wt% or more to 99.9 wt% based on the total weight of the composition. In this case, the diamine hydrochloride salt may contain two HCl bonded to the two terminal amine groups of the diamine.

In addition, the water content of the obtained diamine hydrochloride composition may be 5% or less.

Preparation of diisocyanate composition

Next, the diamine hydrochloride composition is reacted with triphosgene to obtain a diisocyanate composition.

In this case, the reaction of triphosgene with the diamine hydrochloride composition may be performed in a second organic solvent.

Scheme 2 below shows an example of the reaction of this step.

[Scheme 2]

In the above formula, R includes an aromatic ring, an aliphatic ring, an aliphatic chain, and the like, and as a specific example, R may be xylylene, norbornene, xylylene hydride, isophorone or hexamethylene, but is not limited thereto.

Specifically, the diamine hydrochloride composition prepared above is added to an organic solvent, reacted with triphosgene (BTMC, bis(trichloromethyl)carbonate), and then purified to obtain a diisocyanate composition.

Specific examples of the second organic solvent include benzene, toluene, ethylbenzene, chlorobenzene, monochlorobenzene, 1,2-dichlorobenzene (ODCB), dichloromethane, 1-chloro-n-butane, 1-chloro-n- 1 selected from the group consisting of pentane, 1-chloro-n-hexane, chloroform, carbon tetrachloride, n-pentane, n-hexane, n-heptane, n-octane, cyclohexane, cyclopentane, cyclooctane and methylcyclohexane may be more than one species.

The amount (weight) of the second organic solvent may be 1 to 5 times the weight of the diamine hydrochloride composition. When it is within the above dosage range, it is possible to prevent the use of an excessive organic solvent while the yield of the final diisocyanate is high. Specifically, the second organic solvent may be added to the reaction in an amount of 2 to 5 times, or 3 to 5 times the weight of the diamine hydrochloride composition.

When the reaction temperature of the diamine hydrochloride composition and triphosgene is 115° C. or higher, the reaction between the diamine hydrochloride and triphosgene proceeds more smoothly, which may be advantageous in increasing the yield and shortening the reaction time. In addition, when the reaction temperature of the diamine hydrochloride composition and triphosgene is 160° C. or less, generation of impurities such as tar can be suppressed during final diisocyanate production. For example, the reaction temperature of the diamine hydrochloride composition and triphosgene may be 115°C to 160°C, 115°C to 130°C, or 130°C to 160°C.

In addition, when the reaction temperature of the diamine hydrochloride composition and triphosgene is 130° C. or less, it may be more advantageous to suppress chlorine-containing impurities (eg, chloromethylbenzyl isocyanate, 1,3-bis(chloromethyl)benzene, etc.). Specifically, the reaction temperature of the diamine hydrochloride composition and triphosgene may be 115°C to 130°C. More specifically, the reaction temperature of the diamine hydrochloride composition and triphosgene may be 115°C to 120°C.

The reaction of the diamine hydrochloride composition with triphosgene may be performed for 5 to 100 hours. When the reaction time is within the range, the reaction time is not excessive, and generation of unreacted substances due to phosgene generation can be minimized. Specifically, the reaction of the diamine hydrochloride composition with triphosgene may be performed for 15 hours to 40 hours, 20 hours to 35 hours, or 24 hours to 30 hours.

As a specific example, the reaction of the diamine hydrochloride composition with triphosgene may be performed at a temperature of 115° C. to 160° C. for 5 hours to 100 hours.

The diamine hydrochloride composition and the triphosgene may be added to the reaction in an equivalent ratio of 1:1 to 5. When the equivalence ratio is within the range, it is possible to prevent the reaction time from increasing due to excessive input while the reaction efficiency is high. Specifically, the diamine hydrochloride composition and the triphosgene may be added to the reaction in an equivalent ratio of 1: 1.5 to 4, or 1: 2 to 2.5.

The reaction of the diamine hydrochloride composition and triphosgene, the reaction of the diamine hydrochloride composition and triphosgene includes mixing the diamine hydrochloride composition and the second organic solvent to obtain a first solution; mixing triphosgene and the second organic solvent to obtain a second solution; and sequentially adding and stirring the second solution to the first solution. In this case, the input and stirring of the second solution may be performed at a temperature of 115 °C to 160 °C. In addition, the input of the second solution may be divided into two or more times for a total of 25 to 40 hours. In addition, at this time, the input time for each time may be 5 hours to 25 hours, or 10 hours to 14 hours. In addition, the time for further reaction by stirring after the addition may be 2 hours to 5 hours or 3 hours to 4 hours.

Alternatively, the reaction of the diamine hydrochloride composition and triphosgene comprises the steps of (2a) introducing the second organic solvent to a second reactor; (2b) adding and stirring the diamine hydrochloride composition to the second reactor; and (2c) adding and stirring the triphosgene to the second reactor in sequence. At this time, the introduction of the triphosgene in the step (2c) is a solution in which the triphosgene is dissolved in the same solvent as the second organic solvent in the reactor at a temperature of 115°C to 130°C for a total of 25 hours to 40 hours. It may be divided into more than one time. In addition, at this time, the input time for each time may be 5 hours to 25 hours, or 10 hours to 14 hours. In addition, the time for further reaction by stirring after the addition may be 2 hours to 5 hours or 3 hours to 4 hours.

After the reaction, the reaction product may be cooled at 90°C to 110°C.

The product obtained through the reaction may be further subjected to separation, degassing, cooling, filtration, distillation, and the like.

For example, after the reaction, degassing may be performed at 80° C. to 150° C. while bubbling the reaction product with nitrogen gas. In addition, after the degassing, it can be cooled to 10°C to 30°C and filtered to remove the solid content.

The diisocyanate composition may be obtained by distillation after the reaction of the diamine hydrochloride composition with the triphosgene.

The distillation may include distillation to remove the second organic solvent. For example, after the reaction, the resultant of the reaction may be distilled at 40° C. to 60° C. for 2 to 8 hours to remove the second organic solvent. The pressure during the distillation may be 2.0 torr or less, 1.0 torr or less, 0.5 torr or less, or 0.1 torr or less. In addition, the second organic solvent may be recovered and recycled through the distillation.

In addition, the distillation may include distilling the diisocyanate. For example, the distillation may include diisocyanate distillation at 100°C to 130°C. When it is within the above distillation temperature range, it effectively removes hydrolyzable chlorine compounds generated at high temperatures such as chloromethylbenzyl isocyanate (CBI) or 1,3-bis(chloromethyl)benzene in the final optical lens, such as streaks, cloudiness, and yellowing. It may be more advantageous to prevent deterioration of physical properties. Specifically, the distillation may be performed by setting the bottom temperature of the distiller to 100°C to 130°C. For example, the distillation may be performed by setting the temperature of the reboiler to 100°C to 130°C.

In addition, the pressure during the distillation may be 2.0 torr or less, 1.0 torr or less, 0.5 torr or less, or 0.1 torr or less. Specifically, the distillation may include diisocyanate distillation at a temperature of 100° C. to 130° C. and a pressure of 2 torr or less.

In addition, the diisocyanate distillation time may be 1 hour or more, 2 hours or more, or 3 hours or more, and may be 10 hours or less, or 5 hours or less. Specifically, the diisocyanate distillation may be performed for 2 hours to 10 hours.

The yield of the diisocyanate distillation may be 80% or more, specifically 85% or more, or 90% or more. At this time, the distillation yield can be calculated by measuring the yield of the diisocyanate composition after distillation compared to the theoretical production amount of the diisocyanate composition calculated from the amount of the diamine hydrochloride composition added to the reaction with triphosgene.

According to the method of the embodiment, by controlling the reaction temperature range of the diamine hydrochloride composition and triphosgene, there may be very few impurities in the crude diisocyanate composition before purification. Specifically, the diisocyanate composition, before the diisocyanate distillation, may include 99.0% by weight or more of diisocyanate. In addition, the diisocyanate composition, after the diisocyanate distillation, may include the diisocyanate in an amount of 99.9% by weight or more.

In addition, the content of the aromatic compound having a halogen group in the diisocyanate composition may be 1000 ppm or less.

In addition, the yield of the finally obtained diisocyanate composition may be 80% or more, 85% or more, or 90% or more.

Diisocyanate composition

The diisocyanate composition prepared by the above method may have improved color and haze.

The diisocyanate composition may have an American Public Health Association (APHA) color value of 20 or less, or 10 or less. Specifically, the diisocyanate composition may have an APHA color value of 1 to 20, or 1 to 10.

In addition, the haze of the diisocyanate composition may be 10% or less, 5% or less, or 3% or less.

According to the above embodiment, since the diisocyanate composition is prepared using the diamine hydrochloride composition in which the total content of cations is controlled, as a result, the cation content in the diisocyanate composition can also be adjusted. A cation such as a metal contained in the diisocyanate composition may promote a side reaction and cause deterioration of physical properties such as streak in the final optical lens.

The reaction equation below shows the mechanism of promoting the reaction of isocyanate by inducing a catalytic reaction when metal ions remain.

wherein R and R' are each an alkyl group or an aromatic group; X of R′-X is —OH, —NH ₂ , or —SH; M is an alkali metal ion or an alkaline earth metal ion; X of MX ₂ is a halogen element.

For example, the total content of cations in the diisocyanate composition may be 100 ppm or less, 50 ppm or less, or 10 ppm or less. Specifically, the total content of cations in the diisocyanate composition may be 5 ppm or less. In this case, the content range may be a value after purification by distillation.

In addition, for the diisocyanate composition having the above cation content range, the reactivity (polymerization rate) of the polymerizable composition using the same may be appropriate. Specifically, the polymerizable composition using the diisocyanate composition may have a rate of change of viscosity with time in Equation 1, that is, a b value of 0.1 to 0.3, specifically 0.13 to 0.28, 0.13 to 0.25, or 0.15 to 0.23. .

[Equation 1]

Y= a x exp(b x X)

In the above formula, Y is the viscosity (cPs) of the polymerizable composition, X is the elapsed time (hr) after preparing the polymerizable composition, for example, a variable of 5 to 24, a is the initial viscosity (cPs) as a constant, Depending on the polymerization conditions, it can be set, for example, between 20 and 1000 and does not affect the determination of the b value.

The cation in the diisocyanate composition may include an ion of one or more metals selected from the group consisting of Fe, Na, Ca, Mg, Cr, Mn, Ni, Cu, and Zn.

As a specific example, the content of Fe ions in the diisocyanate composition may be 2 ppm or less.

In addition, the content of diisocyanate in the diisocyanate composition may be 90% by weight or more, 95% by weight or more, or 99.5% by weight or more, and specifically may be 90% by weight to 99.9% by weight.

In addition, the diisocyanate composition may further include benzyl isocyanate, methylbenzyl isocyanate, cyanobenzyl isocyanate, and the like, and the total content of these components may be 1% by weight or less.

The diisocyanate composition may include xylylene diisocyanate or other diisocyanates used in the manufacture of optical lenses, specifically ortho-xylylene diisocyanate (o-XDI), meta-xylylene diisocyanate (m-XDI) 1 selected from the group consisting of , para-xylylene diisocyanate (p-XDI), norbornene diisocyanate (NBDI), hydrogenated xylylene diisocyanate (H6XDI), isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI) It may include more than one species.

According to the method of the above embodiment, the yield of diisocyanate is high, the recycling rate of the organic solvent is excellent, and it is eco-friendly because it does not use toxic phosgene gas, and it does not require a separate device for pressurization or rapid cooling.

Measurement of color and transparency of reaction solution

The step of obtaining a diisocyanate composition from the diamine hydrochloride composition and triphosgene includes: (i) reacting the diamine hydrochloride composition in a reactor with triphosgene in a second organic solvent to obtain a reaction solution; (ii) measuring the color and transparency of the reaction solution; and (iii) obtaining a diisocyanate composition from the reaction solution.

In the reaction of the diamine hydrochloride composition and triphosgene, the reaction conditions can be adjusted by measuring the color and transparency of the reaction solution.

For example, in the reaction of obtaining metaxylylenediisocyanate from metaxylylenediamine hydrochloride and triphosgene, the reaction solution at the initial stage of the reaction may be opaque, colorless to white, and the reaction solution at the time when the reaction is normally completed is transparent or transparent It is close to and may have a light brown color.

For example, in the step of measuring the color and transparency of the reaction solution, the reaction solution may exhibit a transparent light brown color.

Specifically, the reaction solution may have an L* value of 45 to 60, an a* value of 3 to 15, and a b* value of 15 to 30 in the CIE-LAB color coordinate. More specifically, the reaction solution may have an L* value of 50 to 55, an a* value of 5 to 10, and a b* value of 20 to 25 in the CIE-LAB color coordinates.

In addition, the reaction solution may have a transmittance of 60% or more, 70% or more, 80% or more, or 90% or more for light having a wavelength of 550 nm. In addition, the reaction solution may have a haze of 20% or less, 10% or less, 5% or less, or 3% or less. Specifically, the reaction solution may have a transmittance of 70% or more and a haze of 10% or less for light having a wavelength of 550 nm. More specifically, the reaction solution may have a transmittance of 80% or more and a haze of 5% or less for light having a wavelength of 550 nm.

On the other hand, if the reaction between metaxylylenediamine hydrochloride and triphosgene is not completed, the reaction solution may be opaque or have a precipitate, and the color may be faint, white, or colorless. In addition, if a large number of side reactions occur, the reaction solution may be opaque or may exhibit a color other than light brown, for example, may exhibit a dark brown to dark color.

The reaction step of the diamine hydrochloride composition and triphosgene may be performed simultaneously with the step of measuring the color and transparency of the reaction solution.

That is, the color and transparency of the reaction solution can be measured in real time while the reaction of the diamine hydrochloride composition and triphosgene is in progress.

In addition, for more accurate measurement, color and transparency can be precisely measured by collecting a part of the reaction solution. For example, the measurement of the color and transparency of the reaction solution may be performed by collecting a portion of the reaction solution and measuring the color and transparency of the collected reaction solution.

In this case, the reaction equivalent, reaction temperature, or reaction time may be adjusted according to the color and transparency of the reaction solution. For example, the reaction end time may be determined according to the color and transparency of the reaction solution. Specifically, the completion time of the reaction may be after the time when the reaction solution changes to a transparent light brown color.

As an example, the reactor may have a viewing window, and measurement of color and transparency of the reaction solution may be performed through the viewing window.

The reactor may be connected to one or more condensers, and after the gas generated in the reactor is transferred to the one or more condensers, the second organic solvent present in the gas may be condensed and recovered to the reactor.

The one or more condensers are connected to the first scrubber and the second scrubber, and the gas transferred from the reactor to the one or more condensers includes hydrogen chloride gas and phosgene gas, and the first scrubber is the hydrogen chloride gas in water. Dissolving to produce an aqueous solution, the second scrubber can neutralize the phosgene gas by the aqueous NaOH solution.

In addition, the reactor may be connected to one or more stills, and the reaction solution may be transferred to the one or more stills, and the one or more stills may separate the diisocyanate composition and the second organic solvent from the reaction solution.

The separated second organic solvent may be recycled for the reaction between the diamine hydrochloride composition and triphosgene.

2 shows an example of a process device for the reaction of a diamine hydrochloride composition and triphosgene.

First, a second organic solvent and triphosgene are filled in the first tank T-1, and a constant temperature is maintained by reflux of hot water. The inside of the reactor (R-1) is substituted with nitrogen, a second organic solvent is added thereto, and while stirring, the diamine hydrochloride composition is slowly added and stirred while maintaining the inside of the reactor at a constant temperature.

Then, triphosgene in the second organic solvent is slowly introduced into the reactor (R-1) from the first tank (T-1). The introduction of triphosgene in the second organic solvent is performed once or in two or more divided times, and at this time, stirring is performed while maintaining the internal temperature of the reactor (R-1) constant. After the addition is completed, an additional reaction is performed while stirring for a certain period of time. As an example, the color and transparency of the reaction solution are visually observed through the viewing window (G-1) provided in the reactor (R-1). As another example, the color and transparency of the reaction solution are measured with an optical device through the viewing window (G-1) provided in the reactor (R-1). The optical device may include a digital camera, a spectrometer, an optical analysis device, and the like.

The gas (second organic solvent, hydrogen chloride, phosgene, etc.) existing inside the reactor R-1 is transferred to the first condenser C-1. The second organic solvent is primarily condensed by cooling in the first condenser (C-1) and recovered to the reactor (R-1), and the remaining gas is transferred to the second condenser (C-2). The second organic solvent is secondarily condensed by cooling in the second condenser (C-2) and recovered to the reactor (R-1), and the remaining gas is transferred to the third condenser (C-3). The second organic solvent is tertiarily condensed by cooling in the third condenser (C-3) and is recovered to the reactor (R-1).

As described above, after the second organic solvent is removed through the multi-stage condenser, the remaining gas (hydrogen chloride, phosgene, etc.) is transferred to the first scrubber S-1. Hydrochloric acid aqueous solution is obtained by dissolving hydrogen chloride gas in water in the first scrubber S-2, and stored in the second tank T-2, and the remaining gas is transferred to the second scrubber S-2. In the second scrubber (S-2), using the sodium hydroxide aqueous solution stored in the third tank (T-3), phosgene (COCl ₂ ) It can be removed by neutralizing the gas.

The reaction solution obtained in the reactor (R-1) is sequentially transferred to the first still (D-1) and the second still (D-2), and through primary and secondary distillation, diisocyanate from the reaction solution The composition and the second organic solvent are separated.

The second organic solvent separated from the reaction solution may be transferred to and stored in the solvent recovery unit V-1, and then may be recycled for the reaction between the diamine hydrochloride composition and triphosgene.

In addition, the diisocyanate composition separated from the reaction solution may be provided as a final product through further filtration and drying.

[Manufacturing method of optical lens]

A composition for an optical material may be prepared by combining the diisocyanate prepared in the above embodiment with other components.

That is, the composition for an optical material includes the diisocyanate prepared according to the embodiment, and a thiol or episulfide.

An optical material, specifically, an optical lens may be manufactured by using the composition for an optical material. For example, an optical lens may be manufactured by mixing the composition for an optical material and curing by heat in a mold.

A method of manufacturing an optical lens according to an embodiment comprises the steps of (1) reacting a diamine composition with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; (2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition; and (3) mixing the diisocyanate composition with thiol or episulfide and polymerizing and curing in a mold, prior to step (2), the diamine hydrochloride composition is dissolved in a solvent having a polarity of 6.2 to 9.8. Further comprising the step of recrystallization after dissolution, the total content of cations in the diisocyanate composition is adjusted to 100 ppm or less.

The thiol may be a polythiol including two or more SH groups, and may have an aliphatic, alicyclic, or aromatic skeleton. The episulfide may have two or more thioepoxy groups, and may have an aliphatic, alicyclic, or aromatic skeleton.

Specific examples of the thiol include bis(2-mercaptoethyl)sulfide, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 2,3-bis(2-mercaptoethylthio ) Propane-1-thiol, 2,2-bis(mercaptomethyl)-1,3-propanedithiol, tetrakis(mercaptomethyl)methane, 2-(2-mercaptoethylthio)propane-1,3 -dithiol, 2-(2,3-bis(2-mercaptoethylthio)propylthio)ethanethiol, bis(2,3-dimercaptopropanyl)sulfide, bis(2,3-dimercaptopropanyl) ) disulfide, 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane, 1,2-bis(2-(2-mercaptoethylthio)-3-mercaptopropylthio)ethane; Bis(2-(2-mercaptoethylthio)-3-mercaptopropyl)sulfide, bis(2-(2-mercaptoethylthio)-3-mercaptopropyl)disulfide, 2-(2-mer Captoethylthio)-3-2-mercapto-3-[3-mercapto-2-(2-mercaptoethylthio)-propylthio]propylthio-propane-1-thiol, 2,2-bis-( 3-Mercapto-propionyloxymethyl)-butyl ester, 2-(2-mercaptoethylthio)-3-(2-(2-[3-mercapto-2-(2-mercaptoethylthio)- Propylthio]ethylthio)ethylthio)propane-1-thiol, (4R,11S)-4,11-bis(mercaptomethyl)-3,6,9,12-tetrathiatetradecane-1,14-diti ol, (S)-3-((R-2,3-dimercaptopropyl)thio)propane-1,2-dithiol, (4R,14R)-4,14-bis(mercaptomethyl)-3, 6,9,12,15-pentathiaheptane-1,17-dithiol, (S)-3-((R-3-mercapto-2-((2-mercaptoethyl)thio)propyl)thio) Propyl)thio)-2-((2-mercaptoethyl)thio)propane-1-thiol, 3,3′-dithiobis(propane-1,2-dithiol), (7R,11S)-7,11 -bis(mercaptomethyl)-3,6,9,12,15-pentathiaheptadecane-1,17-dithiol, (7R,12S)-7,12-bis(mercaptomethyl)-3,6 ,9,10,13,16-hexathiaoctadecane-1,18-dithiol, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithioundecane, 4,7 -Dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, penta erythritol tetra Kiss (3-mercaptopropionate), trimethylolpropane tris (3-mercaptopropionate), pentaethritol tetrakis (2-mercaptoacetate), bispentaerythritol-ether-hexakis ( 3-mercaptopropionate), 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(mercaptodimethylthio)ethyl)-1,3-dithiane, 2,5-bismercaptomethyl-1,4 -dithiane, bis(mercaptomethyl)-3,6,9-trithiaundecan-1,11-dithiol, and the like.

Preferably, the thiol is 2-(2-mercaptoethylthio)propane-1,3-dithiol, 2,3-bis(2-mercaptoethylthio)propane-1-thiol, 2-(2, 3-bis(2-mercaptoethylthio)propylthio)ethanethiol, 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane, 1,2-bis(2-(2-mercapto) Ethylthio)-3-mercaptopropylthio)-ethane, bis(2-(2-mercaptoethylthio)-3-mercaptopropyl)sulfide, 2-(2-mercaptoethylthio)-3-2 -Mercapto-3-[3-mercapto-2-(2-mercaptoethylthio)-propylthio]propylthio-propane-1-thiol, 2,2'-thiodiethanethiol, 4,14-bis (Mercaptomethyl)-3,6,9,12,15-pentathiahexadecane-1,17-dithiol, 2-(2-mercaptoethylthio)-3-[4-(1-{4- [3-Mercapto-2-(2-mercaptoethylthio)-propoxy]-phenyl}-1-methylethyl)-phenoxy]-propane-1-thiol, pentaerythritol tetrakis (3-mercapto propionate), pentaerythritol mercapto acetate, trimethylolpropane trismercaptopropionate, glycerol trimercaptopropionate, dipentaepitritol hexamercaptopropionate, 2,5-bismercaptomethyl -1,4-dithiane, or the like. The thiol may be any one or two or more of the exemplary compounds, but is not limited thereto.

In addition, specific examples of the episulfide include bis(β-epithiopropylthio)methane, 1,2-bis(β-epithiopropylthio)ethane, 1,3-bis(β-epithiopropylthio)propane , 1,2-bis(β-epithiopropylthio)propane, 1-(β-epithiopropylthio)-2-(β-epithiopropylthiomethyl)propane, 1,4-bis(β-epithio Propylthio)butane, 1,3-bis(β-epithiopropylthio)butane, 1-(β-epithiopropylthio)-3-(β-epithiopropylthiomethyl)butane, 1,5-bis( β-epithiopropylthio)pentane, 1-(β-epithiopropylthio)-4-(β-epithiopropylthiomethyl)pentane, 1,6-bis(β-epithiopropylthio)hexane, 1- (β-epithiopropylthio)-5-(β-epithiopropylthiomethyl)hexane, 1-(β-epithiopropylthio)-2-[(2-β-epithiopropylthioethyl)thio]ethane , 1-(β-epithiopropylthio)-2-[[2-(2-β-epithiopropylthioethyl)thioethyl]thio]ethane, tetrakis(β-epithiopropylthiomethyl)methane, 1 ,1,1-tris(β-epithiopropylthiomethyl)propane, 1,5-bis(β-epithiopropylthio)-2-(β-epithiopropylthiomethyl)-3-thiapentane, 1, 5-bis(β-epithiopropylthio)-2,4-bis(β-epithiopropylthiomethyl)-3-thiapentane, 1-(β-epithiopropylthio)-2,2-bis(β -Epithiopropylthiomethyl)-4-thiahexane, 1,5,6-tris(β-epithiopropylthio)-4-(β-epithiopropylthiomethyl)-3-thiahexane, 1,8- Bis(β-epithiopropylthio)-4-(β-epithiopropylthiomethyl)-3,6-dithiaoctane, 1,8-bis(β-epithiopropylthio)-4,5-bis( β-epithiopropylthiomethyl)-3,6-dithiaoctane, 1,8-bis(β-epithiopropylthio)-4,4-bis(β-epithiopropylthiomethyl)-3,6- Dithiaoctane, 1,8-bis(β-epithiopropylthio)-2,4,5-tris(β-epithiopropylthiomethyl)-3,6-dithiaoctane, 1,8-bis(β -epithiopropylthio)-2,5-bis(β-epithiopropylthiomethyl)-3,6-dithiaoctane, 1,9-bis(β-epithiopropylthio)-5-(β-epi Thiopropylthiomethyl)-5-[(2-β -epithiopropylthioethyl)thiomethyl]-3,7-dithianonane, 1,10-bis(β-epithiopropylthio)-5,6-bis[(2-β-epithiopropylthioethyl) Thio]-3,6,9-trithiadecane, 1,11-bis(β-epithiopropylthio)-4,8-bis(β-epithiopropylthiomethyl)-3,6,9-trithia Undecane, 1,11-bis(β-epithiopropylthio)-5,7-bis(β-epithiopropylthiomethyl)-3,6,9-trithiaundecane, 1,11-bis(β -epithiopropylthio)-5,7-[(2-β-epithiopropylthioethyl)thiomethyl]-3,6,9-trithioundecane, 1,11-bis(β-epithiopropylthio )-4,7-bis(β-epithiopropylthiomethyl)-3,6,9-trithioundecane, 1,3-bis(β-epithiopropylthio)cyclohexane, 1,4-bis( β-epithiopropylthio)cyclohexane, 1,3-bis(β-epithiopropylthiomethyl)cyclohexane, 1,4-bis(β-epithiopropylthiomethyl)cyclohexane, bis[4-(β -epithiopropylthio)cyclohexyl]methane, 2,2-bis[4-(β-epithiopropylthio)cyclohexyl]propane, bis[4-(β-epithiopropylthio)cyclohexyl]sulfide, 2,5-bis(β-epithiopropylthiomethyl)-1,4-dithiane, 2,5-bis(β-epithiopropylthioethylthiomethyl)-1,4-dithiane, 1,3- Bis(β-epithiopropylthio)benzene, 1,4-bis(β-epithiopropylthio)benzene, 1,3-bis(β-epithiopropylthiomethyl)benzene, 1,4-bis(β- epithiopropylthiomethyl)benzene, bis[4-(β-epithiopropylthio)phenyl]methane, 2,2-bis[4-(β-epithiopropylthio)phenyl]propane, bis[4-(β -epithiopropylthio)phenyl]sulfide, bis[4-(β-epithiopropylthio)phenyl]sulfone, 4,4'-bis(β-epithiopropylthio)biphenyl, and the like.

The episulfide may be any one or two or more of the exemplary compounds, but is not limited thereto. In addition, the episulfide may be a compound in which at least one hydrogen of a thioepoxy group is substituted with a methyl group.

The composition for an optical material may include the diisocyanate composition and the thiol or episulfide in a mixed state or in a separate state. That is, in the polymerizable composition, they may be in a mixed state in contact with each other, or may be in a separated state so as not to contact each other.

The composition for an optical material may include the thiol or episulfide and the diisocyanate composition in a weight ratio of 2:8 to 8:2, 3:7 to 7:3, or 4:6 to 6:4.

A catalyst, a chain extender, a crosslinking agent, a UV stabilizer, an antioxidant, a color inhibitor, a dye, a filler, a mold release agent, and the like may be further added according to the purpose of the composition for the optical material and the optical lens.

After mixing these thiols or episulfides with the diisocyanate composition and other additives and defoaming, they are poured into a mold, and polymerized while slowly rising from a low temperature to a high temperature, and the resin is cured by heating it to manufacture an optical lens.

The temperature of the polymerization reaction may be, for example, 20 °C to 150 °C, specifically 25 °C to 120 °C. In addition, in order to control the reaction rate, a reaction catalyst commonly used in the production of polythiourethane may be added, and specific types thereof are the same as those exemplified above.

In addition, if necessary, the manufactured optical lens has physical or physical or A chemical treatment may be further carried out.

The optical lens manufactured by the above method has excellent optical properties such as transparency, refractive index, and yellowness. For example, the optical lens may have a refractive index of 1.55 or more, specifically, a refractive index of 1.55 to 1.77. Alternatively, the optical lens may have a refractive index of 1.6 or more, specifically, a refractive index of 1.6 to 1.7. In addition, the optical lens may have an Abbe's number of 30 to 50, specifically 30 to 45, or 31 to 40. In addition, the optical lens may have a light transmittance of 80% or more, 85% or more, or 87% or more, which may be a total light transmittance. In addition, the optical lens may have a yellowness (Y.I.) of 30 or less, 25 or less, or 20 or less, for example, 1 to 25, or 10 to 20. Specifically, the optical lens may have a transmittance of 90% or more and a yellowness of 20 or less.

[Example]

More specific examples are exemplified below, but are not limited thereto.

<Preparation of diisocyanate composition>

Example 1

Step (1) Preparation of diamine hydrochloride composition

1009.4 g (9.46 mol) of a 35% aqueous hydrochloric acid solution was added to the reactor, and the internal temperature of the reactor was cooled to 15° C. while stirring. While maintaining the temperature of the reactor at 60° C., 600.0 g (4.4 mol) of m-XDA was added for 1 hour. After completion of the input, the reactor internal temperature was cooled to 10° C. and stirred for 1 hour, 1500.0 g of tetrahydrofuran (THF) was further added, and the reactor internal temperature was cooled to -5° C., followed by further stirring for 1 hour. After completion of the reaction, the diamine hydrochloride composition containing m-XDA·2HCl was separated by vacuum filtration using a filter, and filtered tetrahydrofuran was recovered for reuse. In order to remove the residual solvent and moisture, the residual solvent and moisture in the separated diamine hydrochloride composition were removed at 90° C. and vacuum dried at 0.5 torr.

Step (2) Preparation of diisocyanate composition

In Reactor A, 800 g of the diamine hydrochloride composition and 3,550 g of orthodichlorobenzene (ODCB) prepared in advance were added and heated at about 125° C. while stirring. 950 g of triphosgene (BTMC) and 800 g of ODCB were put into reactor B, stirred and dissolved at about 60° C., and dropped into reactor A over 24 hours while maintaining a temperature of 125° C. to prevent precipitation. After completion of the dropping, stirring was performed for 4 hours, and when the reaction was completed, nitrogen gas was blown into the solvent at 125° C. and degassed while bubbling. After cooling to 10° C., the remaining solid was filtered using Celite, and the organic solvent (ODCB) was removed and distilled to obtain a diisocyanate composition containing m-XDI. At this time, the organic solvent was removed at a pressure of 0.5 torr or less and a temperature of 60° C. for 8 hours, and distillation was performed at a pressure of 0.5 torr or less and a temperature of 120° C. for 10 hours.

Example 2

The procedure of step (1) of Example 1 was repeated to obtain a diamine hydrochloride composition with an input amount of THF of 1400.0 g, and from this, the procedure of step (2) of Example 1 was repeated to obtain a diisocyanate composition.

Example 3

The procedure of step (1) of Example 1 was repeated, but the input amount of THF was 1100.0 g to obtain a diamine hydrochloride composition, and the diamine hydrochloride composition was washed with 2000 g of tetrahydrofuran at 0° C. and dried. The procedure of step (2) of Example 1 was repeated from the dried diamine hydrochloride composition to obtain a diisocyanate composition.

Example 4

The procedure of step (1) of Example 1 was repeated, but the amount of THF was 800.0 g to obtain a diamine hydrochloride composition, and the diamine hydrochloride composition was washed with 2000 g of tetrahydrofuran at 0° C. and dried. The procedure of step (2) of Example 1 was repeated from the dried diamine hydrochloride composition to obtain a diisocyanate composition.

Comparative Example 1

The procedure of step (1) of Example 1 was repeated to obtain a diamine hydrochloride composition with an input amount of THF of 1100.0 g, and from this, the procedure of step (2) of Example 1 was repeated to obtain a diisocyanate composition.

Comparative Example 2

The procedure of step (1) of Example 1 was repeated to obtain a diamine hydrochloride composition with an input amount of THF of 800.0 g, and from this, the procedure of step (2) of Example 1 was repeated to obtain a diisocyanate composition.

Example 5

Step (1) Preparation of diamine hydrochloride composition

1009.4 g (9.46 mol) of a 35% aqueous hydrochloric acid solution was added to Reactor No. 1, and the internal temperature of the reactor was cooled to 15° C. while stirring. H6XDA 627.0 g (4.4 mol) was added for 1 hour while maintaining the temperature of the reactor below 50 ℃. After completion of the input, the temperature inside the reactor was cooled to 10 ℃ and stirred for 1 hour, and then the internal temperature of the reactor 2, in which 2640.0 g of diethyl ether was added, was cooled to -5 ℃, and then the mixture in the reactor 1 was heated at 0 ℃ or less. It was dripped slowly into the No. 2 reactor. After completion, the diamine hydrochloride composition containing H6XDA·2HCl was separated by vacuum filtration using a filter, and the filtered diethyl ether was recovered for reuse. Thereafter, the separated diamine hydrochloride composition was vacuum dried at 90° C. and 0.5 torr to remove residual solvent and moisture.

Step (2) Preparation of diisocyanate composition

823 g of the diamine hydrochloride composition and 3,550 g of ODCB prepared in the reactor A were added and heated at about 125° C. while stirring. 950 g of triphosgene (BTMC) and 800 g of ODCB were put into reactor B, stirred and dissolved at about 60° C., and dropped into reactor A over 24 hours while maintaining a temperature of 125° C. to prevent precipitation. Stirring was performed for 3-4 hours after completion|finish of dripping. After completion of the reaction, nitrogen gas was blown into the solvent at 125° C. and degassed while bubbling. After cooling to 10° C., the remaining solid was filtered using Celite. A diisocyanate composition containing H6XDI was obtained by performing the removal and distillation process of the organic solvent (ODCB). At this time, the organic solvent was removed at a pressure of 0.5 torr or less and a temperature of 60° C. for 8 hours. In addition, distillation was performed at a temperature of 120 °C and a pressure of 0.5 torr or less for 10 hours.

Example 6

Step (1) Preparation of diamine hydrochloride composition

1009.4 g (9.46 mol) of a 35% aqueous hydrochloric acid solution was added to the reactor, and the internal temperature of the reactor was cooled to 15° C. while stirring. While maintaining the temperature of the reactor at 50 ° C. or less, 490.1 g (4.4 mol) of HDA was added for 1 hour. After completion of the input, the reactor internal temperature was cooled to 10 ℃ and stirred for 1 hour, 1320.0 g of tetrahydrofuran was additionally added, and the reactor internal temperature was cooled to -5 ℃ and further stirred for 1 hour. After completion of the reaction, the diamine hydrochloride composition containing HDA·2HCl was separated by vacuum filtration using a filter, and filtered tetrahydrofuran was recovered for reuse. Thereafter, the separated diamine hydrochloride composition was vacuum dried at 90° C. and 0.5 torr to remove residual solvent and moisture.

Step (2) Preparation of diisocyanate composition

723 g of the diamine hydrochloride composition prepared previously in Reactor A and 3,550 g of ODCB were added and heated at about 125° C. while stirring. 950 g of triphosgene (BTMC) and 800 g of ODCB were put into reactor B, stirred and dissolved at about 60° C., and dropped into reactor A over 24 hours while maintaining a temperature of 125° C. to prevent precipitation. Stirring was performed for 3-4 hours after completion|finish of dripping. After completion of the reaction, nitrogen gas was blown into the solvent at 125° C. and degassed while bubbling. After cooling to 10° C., the remaining solid content was filtered using Celite to obtain a diisocyanate composition containing HDI. Thereafter, organic solvent removal and distillation processes in the diisocyanate composition were performed. At this time, the organic solvent was removed at a pressure of 0.5 torr or less and a temperature of 60° C. for 8 hours. In addition, distillation was performed at a temperature of 120 °C and a pressure of 0.5 torr or less for 10 hours.

Example 7

Step (1) Preparation of diamine hydrochloride composition

1009.4 g (9.46 mol) of a 35% aqueous hydrochloric acid solution was added to Reactor No. 1, and the internal temperature of the reactor was cooled to 15° C. while stirring. While maintaining the temperature of the reactor below 50 ℃ IPDA 812.0 g (4.4 mol) was added for 1 hour. After completion of the input, the temperature inside the reactor was cooled to 10 ℃ and stirred for 1 hour, and then the internal temperature of the reactor 2, in which 2640.0 g of diethyl ether was added, was cooled to -5 ℃, and then the mixture in the reactor 1 was heated at 0 ℃ or less. It was dripped slowly into the No. 2 reactor. After completion, the diamine hydrochloride composition containing IPDA·2HCl was separated by vacuum filtration using a filter, and the filtered diethyl ether was recovered for reuse. Thereafter, the separated diamine hydrochloride composition was vacuum dried at 90° C. and 0.5 torr to remove residual solvent and moisture.

Step (2) Preparation of diisocyanate composition

984 g of the diamine hydrochloride composition and 3,550 g of ODCB prepared in the reactor A were added and heated at about 125° C. while stirring. 950 g of triphosgene (BTMC) and 800 g of ODCB were put into reactor B, and stirred and dissolved at about 60° C., and the temperature was maintained at 125° C. to prevent precipitation, and it was added dropwise to reactor A over 24 hours. Stirring was performed for 3-4 hours after completion|finish of dripping. After completion of the reaction, nitrogen gas was blown into the solvent at 125° C. and degassed while bubbling. After cooling to 10° C., the remaining solid content was filtered using Celite to obtain a diisocyanate composition containing IPDI. Thereafter, organic solvent removal and distillation processes in the diisocyanate composition were performed. At this time, the organic solvent was removed at a pressure of 0.5 torr or less and a temperature of 60° C. for 8 hours. In addition, distillation was performed at a temperature of 120 °C and a pressure of 0.5 torr or less for 10 hours.

Comparative Example 3

A diisocyanate composition was prepared according to the procedure of step (2) of Example 5 using a diamine hydrochloride composition containing H6XDA·2HCl and having a total cation content of more than 200 ppm.

Comparative Example 4

A diisocyanate composition was prepared according to the procedure of step (2) of Example 6 using a diamine hydrochloride composition containing HDA·2HCl and having a total cation content of more than 200 ppm.

Comparative Example 5

A diisocyanate composition was prepared according to the procedure of step (2) of Example 7 using a diamine hydrochloride composition containing IPDA·2HCl and having a total cation content of more than 200 ppm.

<Manufacture of optical lens>

As described in Table 1 below, the diisocyanate composition (main component: m-XDI, H6XDI, HDI or IPDI) prepared in Examples or Comparative Examples, 5,7-dimercaptomethyl-1,11-diol as polythiol A polymerizable composition was prepared by uniformly mixing mercapto-3,6-trithioundecane (BET), and a tin-based catalyst as an additive, and defoaming at 600 Pa for 1 hour.

The polymerizable composition was filtered through a 3 mu m Teflon filter, and poured into a glass mold mold assembled by means of a tape. First polymerization of the polymerizable composition injected into the mold for 3 to 9 hours at a temperature of 10 to 35° C., secondary polymerization for 3 to 9 hours at a temperature of 35 to 60° C., a temperature exceeding 60° C. 3rd polymerization was carried out in 2-7 hours. After polymerization, the plastic molded body (optical lens) was released from the mold, and further curing was performed at 130° C. for 2 hours.

5,7-디메르캅토메틸-1,11-디메르캅토-3,6-트리티아운데칸BET:

5,7-dimercaptomethyl-1,11-dimercapto-3,6-trithiaundecane

m-자일릴렌디이소시아네이트m-XDI:

m-xylylene diisocyanate

수소화 자일릴렌디이소시아네이트H6XDI:

Hydrogenated xylylene diisocyanate

헥사메틸렌디이소시아네이트HDI:

hexamethylene diisocyanate

이소포론디이소시아네이트IPDI:

isophorone diisocyanate

polymeric composition Diisocyanate composition Polythiol (BET) additive type parts by weight chief ingredient parts by weight catalyst Example 1 50.7 m-XDI 49.3 0.01 Example 2 50.7 m-XDI 49.3 0.01 Example 3 50.7 m-XDI 49.3 0.01 Example 4 50.7 m-XDI 49.3 0.01 Example 5 48.6 H6XDI 51.4 0.05 Example 6 48.6 HDI 51.4 0.05 Example 7 48.2 IPDI 54.8 0.05 Comparative Example 1 50.7 m-XDI 49.3 0.01 Comparative Example 2 50.7 m-XDI 49.3 0.01 Comparative Example 3 48.6 H6XDI 51.4 0.05 Comparative Example 4 48.6 HDI 51.4 0.05 Comparative Example 5 48.2 IPDI 54.8 0.05

<Evaluation method>

The Examples and Comparative Examples were evaluated as follows.

(1) Ion content - IC measurement

- Measuring equipment: Ion Chromatography

- Model name: metrohm 882 Compact IC Plus

- Sample pretreatment: In the case of a liquid sample, 2 g of the sample was sonicated in 18 g of water for 1 hour, and only the aqueous layer was collected. In the case of a solid sample, a solution was prepared by dissolving 0.2 g of the sample in 19.8 g of water.

(2) diisocyanate content

The diisocyanate content in the diisocyanate composition was measured by gas chromatography (GC) (instrument: Agilent 6890/7890, carrier gas: He, injection temperature 250° C., oven temperature 40-320° C., column: HP-1, Wax, 30 m, detector: FID, 300°C)

(3) McLee

A lens having a diameter of 75 mm, -2.00, -8.00 D was manufactured, and a Mercury lamp light source was transmitted through the manufactured lens, and the transmitted light was projected on a white plate to determine whether stria occurred by the presence or absence of contrast.

(4) Yellowness (Y.I.) and Transmittance

An optical lens was manufactured in the form of a cylinder having a radius of 16 mm and a height of 45 mm, and light was transmitted in the height direction to measure yellowness and transmittance. The yellowness was calculated by the following equation based on the measurement results of x and y. Y.I = (234x + 106y) / y

(5) refractive index (nd20)

The solid-state refractive index (nd20) was measured at 20°C using an Abbe refractometer DR-M4.

The evaluation results of the above Examples and Comparative Examples are shown in the table below.

(6) Measurement of polymerization rate (reactivity)

With respect to the polymerizable composition, using a non-contact viscometer (EMS-1000, Kyoto Electronics Co., Ltd.) was used to measure the change in viscosity over time at 10°C. At this time, the polymerization rate was calculated as a slope value when the graph was straightened by using the X-axis as time and the Y-axis as the log value of viscosity. Specifically, the change rate (b) of the viscosity (Y) according to the time (X) of the polymerizable composition was derived using Equation 1 below, and then rounded to the third decimal place and summarized in Table 4 below.

[Equation 1]

Y= a x exp(b x X)

In the above formula, Y is the viscosity (cPs) of the polymerizable composition, X is the elapsed time (hr) after preparing the polymerizable composition, for example, a variable of 5 to 24, a is the initial viscosity (cPs) as a constant, Depending on the polymerization conditions, it can be set, for example, between 20 and 1000 and does not affect the determination of the b value.

The results are summarized in the table below.

division Diamine hydrochloride composition Total cation content transference number Example 1 35 ppm 92% Example 2 92 ppm 91% Example 3 135 ppm before washing / 64 ppm after washing 85% Example 4 190 ppm before washing / 88 ppm after washing 84% Example 5 45 ppm 68% Example 6 29 ppm 89% Example 7 25 ppm 71% Comparative Example 1 135 ppm 90% Comparative Example 2 190 ppm 91% Comparative Example 3 156 ppm 71% Comparative Example 4 141 ppm 88% Comparative Example 5 125 ppm 73%

division Diisocyanate composition before distillation Distillation yield (%) after distillation diisocyanate
content (wt%) cation
total content diisocyanate
content (wt%) Example 1 99.3 91 11 ppm 99.9 Example 2 98.9 90 88 ppm 99.9 Example 3 99.2 90 75 ppm 99.9 Example 4 99.1 90 62 ppm 99.9 Example 5 99.1 89 55 ppm 99.9 Example 6 99.1 89 48 ppm 99.8 Example 7 99.0 90 33 ppm 99.8 Comparative Example 1 98.4 88 128 ppm 99.7 Comparative Example 2 98.1 86 150 ppm 99.6 Comparative Example 3 98.3 88 117 ppm 99.2 Comparative Example 4 98.5 87 141 ppm 99.4 Comparative Example 5 98.1 86 130 ppm 99.4

division Reactivity
polymerization rate
(b value) optical lens McLee transmittance Y.I. refractive index Example 1 0.18 radish 91 18 1.670 Example 2 0.23 radish 91 20 1.670 Example 3 0.20 radish 90 20 1.670 Example 4 0.20 radish 90 21 1.670 Example 5 0.22 radish 90 21 1.623 Example 6 0.23 radish 90 21 1.624 Example 7 0.22 radish 90 21 1.596 Comparative Example 1 0.31 Occur 88 21 1.670 Comparative Example 2 0.33 Occur 88 21 1.670 Comparative Example 3 0.29 Occur 89 22 1.623 Comparative Example 4 0.31 Occur 89 21 1.624 Comparative Example 5 0.30 Occur 88 22 1.596

As shown in the table, when the total cation content in the diisocyanate composition is adjusted to 100 ppm or less as in Examples 1 to 7, the polymerization reaction is excellent in quality and the total cation content is small, so that a polymerization reaction at an appropriate rate is possible, and accordingly, the optical lens It was all excellent in terms of stria, transmittance, yellowness and refractive index. In addition, as in Examples 3 and 4, the diamine hydrochloride composition was washed with deionized water and recrystallized to adjust the total cation content to 100 ppm or less. On the other hand, as in Comparative Examples 1 to 5, when the total content of cations in the diisocyanate composition exceeds 100 ppm, the quality of the diisocyanate composition is relatively low and the total content of cations is high, so that the polymerization reaction rate is increased, and accordingly, the optical lens Streaks occurred on the surface, and the transmittance and yellowness were poor.

Claims (11)

(1) reacting the diamine composition with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; and
(2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition,
Prior to step (2), dissolving the diamine hydrochloride composition in a solvent having a polarity of 6.2 to 9.8 and further comprising recrystallizing the composition,
A method for producing a diisocyanate composition, wherein the total content of cations in the diisocyanate composition is controlled to 100 ppm or less. The method of claim 1,
The cation in the diisocyanate composition is Fe, Na, Ca, Mg, Cr, Mn, Ni, Cu, and a method for producing a diisocyanate composition comprising an ion of one or more metals selected from the group consisting of Zn. The method of claim 1,
In the step (1), a first organic solvent is additionally added after the reaction of the diamine composition with the aqueous hydrochloric acid solution to obtain the diamine hydrochloride composition in a solid phase, a method for producing a diisocyanate composition 4. The method of claim 3,
The method for producing a diisocyanate composition, wherein the first organic solvent is added in an amount of 1.3 times to 1.5 times the weight of the aqueous hydrochloric acid solution. 4. The method of claim 3,
The method for producing a diisocyanate composition, wherein the first organic solvent comprises an amphiphilic organic solvent. 4. The method of claim 3,
The first organic solvent is diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, methanol, ethanol, dimethyl sulfoxide, dimethylformamide, acetonitrile, acetone, trichloroethylene, tetrachloroethane, trichloro At least one selected from the group consisting of ethane, n-butanol, isobutanol, methyl ethyl ketone, methyl butyl ketone, isopropanol and methyl acetate, a method for producing a diisocyanate composition. The method of claim 1,
Prior to the step (2), the method for producing a diisocyanate composition, further comprising the step of measuring the total content of cations in the diamine hydrochloride composition. The method of claim 1,
Prior to the step (2), the method for preparing a diisocyanate composition, further comprising the step of washing the diamine hydrochloride composition with a solvent having a polarity index of 3.9 to 5.7. The method of claim 1,
In the recrystallization, an amphiphilic organic solvent, and an aqueous hydrochloric acid solution having a concentration of 20 wt% to 45 wt% are used together, a method for producing a diisocyanate composition. (1) reacting the diamine composition with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition;
(2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition; and
(3) mixing the diisocyanate composition with thiol or episulfide and polymerizing and curing in a mold;
Prior to step (2), dissolving the diamine hydrochloride composition in a solvent having a polarity of 6.2 to 9.8 and further comprising recrystallizing the composition,
A method for producing an optical lens, wherein the total content of cations in the diisocyanate composition is controlled to 100 ppm or less. 11. The method of claim 10,
The method for manufacturing an optical lens, wherein the optical lens has a light transmittance of 90% or more and a yellowness (YI) of 20 or less.

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