KR102456419B1 - Method of preparing diisocyanate composition and optical lens - Google Patents

Abstract

In an embodiment, in the process of preparing diisocyanate from diamine through diamine hydrochloride, an aqueous hydrochloric acid solution and an organic solvent may be used instead of hydrogen chloride gas, and a solid triphosgene may be used instead of phosgene gas. In addition, the embodiment provides a method for producing a diisocyanate composition and an optical lens having excellent yield and quality while reducing environmental problems by adjusting the molar ratio of diamine hydrochloride and triphosgene 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 synthesize isocyanate by reacting the raw amine with phosgene (COCl ₂ ) gas, 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 into an alkyl After reacting with chloroformate to prepare carbamate, it is pyrolyzed at high temperature in the presence of a catalyst to synthesize isocyanate.

Among these isocyanate production methods, the phosgene method is the 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. On the other hand, 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 hydrogen chloride gas with an amine and reacted with phosgene.

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

There is an attempt to obtain hydrochloric acid by using an aqueous solution of hydrochloric acid instead of hydrogen chloride gas, but the amine is dissolved in the aqueous solution of hydrochloric acid and the yield is greatly reduced to 50%, making it difficult to apply in practice. There was a difficulty in using this low amine. 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.

Korean Patent Publication No. 1994-0001948

Accordingly, the present inventors, in the process of producing diisocyanate, which is mainly used as a raw material for plastic optical lenses, from diamine through hydrochloride, use an aqueous hydrochloric acid solution and an organic solvent instead of hydrogen chloride gas, and use solid triphosgene instead of phosgene gas. By controlling them, it was possible to solve the conventional environmental, yield and quality problems.

In addition, the present inventors noted that by controlling the amounts of the diamine hydrochloride composition, triphosgene, and the organic solvent to be added during the preparation of the diisocyanate composition, the yield and purity of the diisocyanate to be prepared can be improved. In particular, the present inventors have discovered that when the molar ratio of the diamine hydrochloride composition and triphosgene is out of a specific range, urea is formed or hydrolysable chlorine is increased, thereby reducing the yield and purity of diisocyanate produced. .

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 adjusting the molar ratio of the diamine hydrochloride composition and triphosgene.

According to an embodiment, (a1) reacting a diamine with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; and (a2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition, wherein the molar ratio of the diamine hydrochloride composition and triphosgene added to the reaction of step (a2) is 1:0.70 to less than 0.95 , a method for preparing a diisocyanate composition is provided.

According to an embodiment, (b1) reacting a diamine with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; (b2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition; and (b3) mixing the diisocyanate composition with thiol or episulfide and polymerizing and curing in a mold, wherein the molar ratio of the diamine hydrochloride composition and triphosgene added to the reaction of step (b2) is 1:0.70 A method of making an optical lens is provided, which is greater than to less than 0.95.

The manufacturing method of diisocyanate according to the above embodiment does not use phosgene gas, which is difficult to store and manage and highly toxic, and uses triphosgene with low toxicity as a solid state at room temperature without requiring a separate cooling storage device. Therefore, it has excellent handling and fairness. In addition, in the method for producing diisocyanate according to the embodiment, by using an aqueous hydrochloric acid solution without using hydrogen chloride gas for the production of diamine hydrochloride, which is an intermediate material, the reaction can proceed even at normal pressure, so that an additional device for high-temperature heating and cooling is provided. It is not necessary and the yield can also be improved.

In addition, the method for producing a diisocyanate composition according to the embodiment uses an organic solvent together with an aqueous hydrochloric acid solution and adjusts the reaction conditions to prepare a diamine hydrochloride composition, thereby minimizing dissolution of the hydrochloride in the aqueous hydrochloric acid solution to further increase the final yield It can be increased, and the range of raw material selection can be broadened as it is not significantly affected by the moisture and impurity content in the raw material diamine.

In particular, according to the above embodiment, by adjusting the molar ratio of diamine hydrochloride and triphosgene within a specific range, the yield and purity of the diisocyanate composition prepared therefrom can be improved, so physical properties such as cloudiness and yellowing in the final optical lens deterioration 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.

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. In addition, in the present specification, the ppm unit means ppm by weight.

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 can 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).

In the present specification, "isocyanate" means a compound having an NCO group, "diisocyanate" means a compound having two NCO groups at the terminal, and according to 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.

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 caused by 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. and "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]

A method for preparing a diisocyanate composition according to an embodiment comprises the steps of (a1) reacting a diamine with an aqueous hydrochloric acid solution to obtain a diamine hydrochloride composition; and (a2) reacting the diamine hydrochloride composition with triphosgene to obtain a diisocyanate composition, wherein the molar ratio of the diamine hydrochloride composition and triphosgene added to the reaction of step (a2) is 1:0.70 to less than 0.95 to be.

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 of low yield.

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 performed 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 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, when the diamine and the aqueous hydrochloric acid solution are added, the internal temperature of the reactor 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 and rapid cooling through a separate cooler is required, 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 comprises at least one of precipitating the diamine hydrochloride composition, filtering the diamine hydrochloride composition, washing the diamine hydrochloride composition, and drying the diamine hydrochloride composition. may contain one.

Specifically, a solid diamine hydrochloride composition may be precipitated by adding a 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 diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, methanol, ethanol, dimethyl sulfoxide, dimethylformamide, acetonitrile, acetone, trichloroethylene, tetrachloroethane, trichloro It may be at least one selected from the group consisting of ethane, 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 an 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, the reaction of this step comprises the steps of (a1-1) introducing the aqueous hydrochloric acid solution into the first reactor; (a1-2) adding and stirring the diamine to the first reactor; and (a1-3) adding and stirring the first organic solvent to the first reactor may be sequentially performed.

More specifically, the reaction of this step may include 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 (a1-2); and cooling the inside of the reactor to a temperature of -5°C to 5°C before stirring after the first organic solvent is added in step (a1-3).

After the first organic solvent is added, 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. In the reaction process for preparing the diamine hydrochloride composition, impurities are generated and 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 above method, a solid diamine hydrochloride composition can be obtained with high purity by reacting the diamine with an aqueous hydrochloric acid solution and performing additional treatment such as precipitation, filtration, washing, and drying. 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 and purification is not easy.

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

In the process of preparing the diamine hydrochloride as described above, 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 a diisocyanate composition is prepared 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 stria, 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 economic 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 of 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* according to the CIE color coordinate It may include adjusting the value to be 1.2 or less.

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 by the above process mainly contains diamine hydrochloride, and the content of diamine hydrochloride based on the total weight of the composition is 50 wt% to 99.9 wt%, 65 wt% to 99.9 wt%, 80 wt% to 99.9 wt% % or from 90% to 99.9% by weight. 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 the diamine hydrochloride composition and triphosgene 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, dichloromethane, 1-chloro-n-butane, 1-chloro-n-pentane, 1 -Chloro-n-hexane, chloroform, carbon tetrachloride, n-pentane, n-hexane, n-heptane, n-octane, cyclohexane, cyclopentane, cyclooctane, and may be at least one selected from the group consisting of methylcyclohexane have.

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 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 within the reaction time 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 a molar ratio of 1:0.70 to less than 0.95 or 1:0.73 to 0.90. When the molar 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, when the molar ratio of the diamine hydrochloride composition and the triphosgene is 1:0.70 or less, the reaction does not proceed sufficiently and the remaining amine reacts with the prepared diisocyanate to form urea, thereby reducing the yield and purity. In addition, when the molar ratio of the diamine hydrochloride composition and the triphosgene is 1:0.95 or more, cloudiness may occur due to the remaining triphosgene, and the content of hydrolyzable chlorine increases, thereby reducing the yield and purity of the diisocyanate produced. have.

The hydrolyzable chlorine is a material produced as a by-reactant in the reaction of the diamine hydrochloride composition and the triphosgene, and can promote quality deterioration such as haze and yellowing of the diisocyanate produced, so that the final optical lens is cloudy and yellowed. can cause deterioration of the lens quality.

The reaction of the diamine hydrochloride composition and triphosgene may include: (a2-1) mixing the diamine hydrochloride composition and a second organic solvent to obtain a first solution; (a2-2) mixing triphosgene and a second organic solvent to obtain a second solution; and (a2-3) adding and stirring the second solution to the first solution in sequence.

The obtaining of the first solution may be performed at a temperature of 115°C to 160°C, and the obtaining of the second solution may be performed at a temperature of 50°C to 70°C. For example, the step of obtaining the first solution may be performed at 115°C to 160°C or 115°C to 130°C, and the step of obtaining the second solution is at a temperature of 50°C to 70°C or 55°C to 65°C. can be performed in

The amount of the second organic solvent added in step (a2-1) may be 4.2 to 4.8 times the weight of the diamine hydrochloride composition, and the amount of the second organic solvent added in step (a2-2) is the triphosgene It may be 0.6 times to 0.9 times the weight of the. 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 diisocyanate is high.

In this case, the input and stirring of the second solution may be performed at a temperature of 115°C to 160°C or 115°C to 130°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 number 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 4.5 hours.

Alternatively, the reaction of the diamine hydrochloride composition with triphosgene is performed by adding the second organic solvent to a second reactor; adding and stirring the diamine hydrochloride composition to the second reactor; And it may include sequentially adding and stirring the triphosgene to the second reactor. At this time, the introduction of the triphosgene 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 160°C or 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 4.5 hours.

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

The product obtained through the above 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 may be cooled to 5° C. to 30° C. or 5° C. to 20° C. and filtered to remove the solid content.

The diisocyanate composition may be obtained by distillation after the reaction of the diamine hydrochloride composition and 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 150°C. When it is within the 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 150°C. For example, the distillation may be performed by setting the temperature of the reboiler to 100°C to 150°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 a 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 1,000 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 by adjusting the molar ratio of the diamine hydrochloride composition and triphosgene, the yield and purity of the diisocyanate can be improved by suppressing side reactions that may occur in the preparation of the diisocyanate composition.

The content of hydrolyzable chlorine that may be generated from the side reaction may be 150 ppm or less or 130 ppm or less. For example, the content of the hydrolyzable chlorine may be 55 ppm to 150 ppm or 55 ppm to 130 ppm. The hydrolyzable chlorine may cause deterioration of physical properties such as cloudiness in the final optical lens.

In addition, the content of the 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 about 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 is possible to react at atmospheric pressure and 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 metaxylylene diisocyanate 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 coordinate.

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 may be precisely measured by collecting a portion 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 end time of the reaction 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 converts the hydrogen chloride gas into 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, the 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 replaced with nitrogen, and a second organic solvent is added thereto and stirred, the diamine hydrochloride composition is slowly added thereto 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 carried out 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 recovered to the reactor (R-1).

In this way, 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 distillation unit (D-1) and the second distillation unit (D-2), and through primary distillation 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 can 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 heat curing in a mold.

A method of manufacturing an optical lens according to an embodiment comprises the steps of (b1) reacting a diamine with an aqueous hydrochloric acid solution in a first organic solvent to obtain a diamine hydrochloride composition; (b2) reacting the diamine hydrochloride composition with triphosgene in a second organic solvent to obtain a diisocyanate composition; and (b3) mixing the diisocyanate composition with thiol or episulfide and polymerizing and curing in a mold, wherein the molar ratio of the diamine hydrochloride composition and triphosgene added to the reaction of step (b2) is 1:0.70 greater than to less than 0.95.

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 mercaptoacetate, trimethylolpropanetrismercaptopropionate, 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 as exemplified above.

In addition, the manufactured optical lens has physical properties such as anti-reflection, high hardness, abrasion resistance, chemical resistance, anti-fogging, surface polishing, antistatic treatment, hard coat treatment, anti-reflection coating treatment, dyeing treatment, etc. Alternatively, a chemical treatment may be further performed.

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, 87% or more, or 90% 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 22 or less, for example, 1 to 25, or 10 to 22. Specifically, the optical lens may have a transmittance of 90% or more and a yellowness of 22 or less.

[Example]

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

Example 1: Preparation of diisocyanate composition

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 temperature inside the reactor was cooled to 10° C. and stirred for 1 hour, 1500.0 g of tetrahydrofuran (THF) was further added, and the temperature inside the reactor 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

800 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) composition and 800 g of orthodichlorobenzene (ODCB) were put into reactor B, stirred and dissolved at about 60° C., and the temperature was maintained at 125° C. to prevent precipitation. It was dropped into reactor A over 24 hours. . After completion of the dropwise addition, stirring was carried out 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 the distillation was performed at a pressure of 0.5 torr or less and a temperature of 120° C. for 10 hours.

Examples 2 to 4 and Comparative Examples 1 to 4

A diisocyanate composition was prepared in the same manner as in Example 1, except that the molar ratio of diamine hydrochloride and triphosgene was changed as shown in Table 1 below.

division Molar ratio of diamine hydrochloride:triphosgene Example 1 1:0.84 Example 2 1:0.90 Example 3 1:0.88 Example 4 1:0.73 Comparative Example 1 1:0.70 Comparative Example 2 1:0.67 Comparative Example 3 1:0.95 Comparative Example 4 1:1.00

<Manufacture of optical lens>

4,8-bis(mercaptomethyl-3,6,9-trithiaundecan-1,11-dithiol 49.3 parts by weight, 50.7 parts by weight of the diisocyanate composition prepared in Examples or Comparative Examples above, dibutyl tin A polymerizable composition was prepared by uniformly mixing 0.01 parts by weight of chloride and 0.1 parts by weight of ZELEC ^® UN Stepan's phosphate ester release agent and defoaming at 600 Pa for 1 hour.

The polymerizable composition was filtered through a 3 μm Teflon filter and injected into a mold made of a glass mold and a tape. After maintaining the mold at 10° C. to 25° C. for 8 hours, the temperature was slowly raised to 130° C. at a constant rate for 8 hours, followed by polymerization at 130° C. for 2 hours. After the molding was released from the mold, it was further cured at 120° C. for 2 hours to obtain an optical lens.

<Evaluation method>

The Examples and Comparative Examples were evaluated as follows.

(1) content of diisocyanate

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

(2) content of hydrolyzable chlorine

It was measured by the method of obtaining|requiring hydrolysable chlorine of the plastic polyurethane raw material aromatic isocyanate test method 3 part prescribed|regulated to JISK1603-3 (2007).

(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) cloudiness

The lens was irradiated with a projector in a dark place, and the presence or absence of a cloudy or opaque material was visually checked. If the lens had no cloudy or opaque material, it was evaluated as no (no cloudiness), and if there was a cloudy or opaque material, it was evaluated as present (with cloudiness).

(5) Yellowness (Y.I)

An optical lens was manufactured in the form of a cylinder having a radius of 16 mm and a height of 45 mm, and the light was transmitted in the height direction to measure the yellowness. Yellowness was calculated by the following equation based on the measurement results of x and y.

Y.I = (234x + 106y) / y

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

division Diisocyanate composition distillation yield
(%) Diisocyanate content (wt%) Content of hydrolyzable chlorine (ppm) Example 1 88 99.9 68 Example 2 91 99.9 110 Example 3 89 99.9 84 Example 4 86 99.9 55 Comparative Example 1 77 99.8 54 Comparative Example 2 65 99.7 45 Comparative Example 3 90 99.7 215 Comparative Example 4 91 99.7 890

division optical lens McLee cloudiness Y.I. Example 1 radish radish 19 Example 2 radish radish 22 Example 3 radish radish 19 Example 4 radish radish 19 Comparative Example 1 radish you 20 Comparative Example 2 radish you 21 Comparative Example 3 radish you 25 Comparative Example 4 radish you 28

As shown in the table above, when the molar ratio of diamine hydrochloride and triphosgene is adjusted to greater than 1:0.70 to less than 0.95 as in Examples 1 to 4, the content of hydrolyzable chlorine is controlled to 150 ppm or less, the final prepared therefrom All of the optical lenses were excellent in terms of streaks, white turbidity and yellowness.

On the other hand, as in Comparative Examples 1 to 4, when the molar ratio of diamine hydrochloride and triphosgene does not satisfy 1:0.70 to less than 0.95, Comparative Examples 1 and 2 have hydrolyzable chlorine content of 150 ppm or less, but cloudy In Comparative Examples 3 and 4, the content of the hydrolyzable dye was more than 150 ppm, and both were poor in terms of cloudiness and yellowness.

Claims (13)

(a1) reacting diamine with an aqueous hydrochloric acid solution in a first organic solvent to obtain a diamine hydrochloride composition in a solid phase; and
(a2) reacting the diamine hydrochloride composition with triphosgene in a second organic solvent to obtain a diisocyanate composition,
In the step (a1), (a1-1) adding the aqueous hydrochloric acid solution to the first reactor, (a1-2) adding and stirring the diamine to the first reactor, and (a1-3) the first reactor Including sequentially introducing and stirring the first organic solvent in one reactor,
In step (a2), the second organic solvent is added in an amount of 3 to 5 times the weight of the diamine hydrochloride composition,
The molar ratio of the diamine hydrochloride composition and triphosgene added to the reaction of step (a2) is 1:0.70 to less than 0.95,
The first organic solvent is diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, methanol, ethanol, dimethyl sulfoxide, dimethylformamide, acetone, trichloroethylene, tetrachloroethane, trichloroethane, n- At least one selected from the group consisting of butanol, isobutanol, methyl ethyl ketone, methyl butyl ketone, isopropanol, hexane, chloroform and methyl acetate, a method for producing a diisocyanate composition. The method of claim 1,
In the step (a1), a first organic solvent is further 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. The method of claim 1,
The step (a2) is
(a2-1) mixing the diamine hydrochloride composition and a second organic solvent to obtain a first solution;
(a2-2) mixing triphosgene and the second organic solvent to obtain a second solution; and
(a2-3) A method for producing a diisocyanate composition comprising sequentially adding and stirring the second solution to the first solution. 4. The method of claim 3,
The step (a2-3) is carried out at 115 ℃ to 160 ℃, the method for producing a diisocyanate composition. 4. The method of claim 3,
In the step (a2-1), the second organic solvent is added to the reaction in an amount of 4.2 to 4.8 times the weight of the diamine hydrochloride composition, the method for producing a diisocyanate composition. 4. The method of claim 3,
In the step (a2-2), the second organic solvent is added to the reaction in an amount of 0.6 to 0.9 times the weight of the triphosgene, the method for producing a diisocyanate composition. The method of claim 1,
The diamine is xylylenediamine,
The method for producing a diisocyanate composition, wherein the diisocyanate composition comprises xylylene diisocyanate. The method of claim 1,
The method for producing a diisocyanate composition, wherein the aqueous hydrochloric acid solution has a concentration of 20 wt% to 45 wt%. The method of claim 1,
The diisocyanate composition is obtained by distillation after the reaction of the diamine hydrochloride composition with the triphosgene,
The method for producing a diisocyanate composition, wherein the distillation comprises diisocyanate distillation at a temperature of 100°C to 150°C and a pressure condition of 2 torr or less. 10. The method of claim 9,
The yield of the diisocyanate distillation is 85% or more,
The method for producing a diisocyanate composition, wherein the diisocyanate composition comprises at least 99.9% by weight of diisocyanate after diisocyanate distillation. 10. The method of claim 9,
The method for producing a diisocyanate composition, wherein the diisocyanate composition contains 150 ppm or less of hydrolysable chlorine after the diisocyanate distillation. (b1) reacting diamine with an aqueous hydrochloric acid solution in a first organic solvent to obtain a diamine hydrochloride composition in a solid phase;
(b2) reacting the diamine hydrochloride composition with triphosgene in a second organic solvent to obtain a diisocyanate composition; and
(b3) mixing the diisocyanate composition with thiol or episulfide and polymerizing and curing in a mold;
In the step (b1), (a1-1) introducing the aqueous hydrochloric acid solution into the first reactor, (a1-2) adding and stirring the diamine to the first reactor, and (a1-3) the first reactor Including sequentially introducing and stirring the first organic solvent in one reactor,
In the step (b2), the second organic solvent is added in an amount of 3 to 5 times the weight of the diamine hydrochloride composition,
The molar ratio of the diamine hydrochloride composition and triphosgene added to the reaction of step (b2) is 1:0.70 to less than 0.95,
The first organic solvent is diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, methanol, ethanol, dimethyl sulfoxide, dimethylformamide, acetone, trichloroethylene, tetrachloroethane, trichloroethane, n- At least one selected from the group consisting of butanol, isobutanol, methyl ethyl ketone, methyl butyl ketone, isopropanol, hexane, chloroform and methyl acetate, a method of manufacturing an optical lens. 13. The method of claim 12,
The method for manufacturing an optical lens, wherein the optical lens has a yellowness (YI) of 22 or less.

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