KR20190086257A - Manufacturing method of isocyanate compound for optical material - Google Patents

Abstract

The present invention relates to a method for manufacturing an isocyanate compound for an optical material and, more specifically, to a method for effectively manufacturing an isocyanate compound for an optical material by using a specific catalyst. When manufacturing meta-xylylene-diisocyanate by synthesizing and purifying diamine and carbonate in the presence of a solvent and a catalyst, an isocyanate compound with high purity can be manufactured due to the low impurity content in the isocyanate compound for an optical material by using diamine with the low impurity content and a specific catalyst. In addition, a lens has high quality due to low yellow index.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an isocyanate compound for optical materials,

The present invention relates to a process for producing an isocyanate compound for an optical material, and more particularly, to a process for effectively producing an isocyanate compound for an optical material by using a specific catalyst.

Generally, the phosgene method using phosgene has been mainly used for producing the isocyanate compound, but it is difficult to use the phosgene because of environmental pollution and toxicity.

The isocyanate compound is an indispensable material for an optical material. The production of an isocyanate compound having a high purity and a low yellowness is a problem of directly producing a high quality optical lens (optical material) which is colorless transparent, has a high refractive index, , It is necessary to solve the problem of raising the quality of the isocyanate compound.

An object of the present invention is to provide a method for producing an isocyanate compound for an optical material, which can produce a lens having a low total moisture content of raw materials and a low impurity content of amines in raw materials and having high purity and quality.

Another object of the present invention is to provide an optical material isocyanate compound suitable for use as an optical lens because it has high purity and low yellowing degree by lowering the moisture content and the impurity concentration in an isocyanate compound produced by using a specific catalyst.

In order to achieve the above object, the present invention provides a process for producing an isocyanate compound for optical materials,

Synthesis and purification of meta-xylylene diamine and bis (trichloromethyl) carbonate at a temperature of -20 to 180 占 폚 in a solvent and a catalyst to prepare meta-xylylene diisocyanate Wherein the catalyst is one or more selected from the group consisting of 4-Hydroxy-TEMPO, 4-nitrophenol and phenol.

 In one specific example, the total content of cyan compound, nitro compound, and iron (Fe), which are impurities in the meta-xylylenediamine, is 0.3% or less.

In another specific example, the total content of the chlorine compound and the cyanine compound in the produced isocyanate compound for an optical material is 0.3% or less.

In one specific example, the produced isocyanate compound for an optical material is purified at 60 to 150 ° C under 0.0001 to 100 mmHg to have a purity of 99% or more and an APHA value of 15 or less.

Examples of the solvent usable in the present invention include benzene, toluene, ethylbenzene, chlorobenzene, monochlorobenzene, 1,2-dichlorobenzene, 1-chloro-n-pentane, 1-chloro-n-hexane (1-chloro-n-butane) n-pentane, n-hexane, n-heptane, n-heptane, n-heptane, Is at least one member selected from the group consisting of n-octane, cyclohexane, cyclopentane, cyclooctane, and methyl cyclohexane.

As described above, in the production of the isocyanate compound for optical materials according to the present invention, in the production of meta-xylylene diisocyanate by synthesizing and purifying a diamine and a carbonate in a solvent and a catalyst, use of a diamine having a low impurity content, It is possible to produce an isocyanate compound having a high purity due to a low content of impurities in the isocyanate compound for an optical material produced by the use of the above-mentioned isocyanate compound for an optical material, and also has an effect of achieving high quality of a lens because of low yellowness index.

In the present invention, the isocyanate compound is characterized by a process for producing methacrylsilane diisocyanate.

First, an isocyanate compound means a compound containing an N = C = O- functional group, and a diisocyanate is a compound having two N = C = O-functional groups, that is, a compound containing two isocyanate groups It is a generic term to denote.

 Diisocyanates having two isocyanate functional groups generally have a structure of O = C = N-hard segment -N = C = O, wherein the hard segment is generally an aromatic ring structure or an aliphatic or alicyclic And the polyisocyanate means a structure in which such a hard segment is repeated.

Isocyanates vary according to the structure of these hard segments, which can be divided into aromatic isocyanates and aliphatic isocyanates, and aromatic diisocyanates with aromatic rings are most commonly used.

Specific examples of the (poly) isocyanate compound in general include hexamethylene diisocyanate, 2,5-bis (isocyanatomethyl) -bicyclo [2.2.1] heptane, 2,6-bis (isocyanatomethyl) -Bicyclo [2.2.1] heptane, bis (isocyanatomethyl) cyclohexane, dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,2-diisocyanatobenzene, 1,3- Diisocyanatotoluene, ethylphenylene diisocyanate, dimethylphenylene diisocyanate, trimethylbenzene triisocyanate, benzene triisocyanate, biphenyl diisocyanate, toluidine diisocyanate, 4,4'-diisocyanatobenzene, (Isocyanatomethyl) benzene, 1,2-bis (isocyanatomethyl) benzene, 1,3-bis (isocyanatomethyl) benzene, - bis (isocyanatoethyl) benzene, 1,3-bis (Isocyanatoethyl) benzene, 1,4-bis (isocyanatoethyl) benzene,?,?,? '- tetramethyl xylylene diisocyanate, bis (isocyanatomethyl) naphthalene, bis Bis (isocyanatomethyl) sulfide, bis (isocyanatopropyl) sulfide, 2,5-diisocyanatotetrahydrothiophene, 2,5-diisocyanate Diisocyanatomethyltetrahydrothiophene, 2,5-diisocyanato-1,4-dithiane, 2,5-diisocyanatomethyl-1,4-dithiane, , And the like.

Further, there may be mentioned chlorine substituents, halogen substituents such as bromine substituents, alkyl substituents, alkoxy substituents, prepolymer type modified products with nitric acid substituents or polyhydric alcohols, carbodiimide modified products, urea modified products, biuret modified products, A reaction product or the like may also be used.

In general, preferred amines used for producing isocyanates are not particularly limited to chain-like aliphatic amines or cyclic aliphatic amines, but typical examples thereof include hexamethylenediamine, 2,2-dimethylpentanediamine, 2,2,4-trimethylhexanediamine Butene diamine, 1,3-butadiene-1,4-diamine, 2,4,4-trimethylhexamethylene diamine, 1,6,11-undecatriamine, 1,3,6-hexamethylene triamine, Bis (aminoethyl) carbonate, bis (aminoethyl) ether, lysindiaminomethyl ester, lysine triamine, xylylenediamine, bis (aminoethyl) carbonate, Benzene, bis (aminopropyl) benzene, alpha, alpha, alpha ', alpha'-tetramethyl xylylenediamine, bis (aminobutyl) benzene, bis (aminomethyl) naphthalene, bis (Aminoethyl) phthalate, mesitylethylenetriamine, 2,6-di (amino (Aminomethyl) cyclohexane, dicyclohexylmethanediamine, cyclohexanediamine, methylcyclohexanediamine, dicyclohexyldimethylmethanediamine, 2,2-dimethyldicyclohexylmethanediamine , 2,6-bis (aminomethyl) bicyclo- [2,2,1] -heptane, 3,8-bis (Aminomethyl) tricyclodecane, 4,9-bis (aminomethyl) tricyclodecane, bis (aminomethyl) tricyclodecane, 4,9- (Aminoethyl) sulfide, bis (aminopropyl) sulfide, bis (aminomethyl) sulfone, bis (aminomethyl) sulfone, bis (Aminomethyl) disulfide, bis (aminoethyl) disulfide, bis (aminopropyl) disulfide, bis (aminomethylthio) Containing chain aliphatic amines such as methane, bis (aminoethylthio) ethane, bis (aminomethylthio) ethane and 1,5-diamino-2-aminomethyl-3-thiapentane.

As the amine used in the present invention, meta-xylylenediamine of the following structural formula is used.

(m-xylylene diamine)

(m-xylylene diamine)

In order to prepare such an isocyanate compound, an amine hydrochloride is generally prepared by reacting a (di) amine formed by condensing aniline and formaldehyde with hydrogen chloride, and isocyanate is produced through phosgenation in which phosgene is reacted with the obtained amine hydrochloride There is a phosgenation process.

The above-mentioned isocyanates have been synthesized from amines and phosgene (COCl 2). However, in this case, there is a problem of the toxicity characteristic of the phosgene gas. When the phosgene leaks, the non-phosgene- A phosgenation process is required.

Accordingly, the present invention is characterized in that meta-xylylene diisocyanate is produced by using diamine and bis (trichloromethyl) carbonate, i.e., triphosgene, to produce an aromatic isocyanate compound, meta-xylylene diisocyanate.

Bis (trichloromethyl) carbonate, that is, the triphosgene is a safer substitute compound of phosgene and has a solid form at room temperature, so that gas leakage does not occur compared with phosgene gas, thereby solving the problem of environmental pollution. It is a substituent that is less toxic than phosgene gas.

A method for producing an isocyanate compound for an optical material according to the present invention is as follows.

First, meta-xylylene diamine and bis (trichloromethyl) carbonate (triphosgene) are synthesized in a solvent and a catalyst at a temperature of -20 to 180 ° C.

In this case, the preferred reaction temperature is -20 to 180 ° C, more preferably, the first reaction temperature is -20 to 10 ° C, the second reaction temperature is 120 to 180 ° C, Preferably, the first stage reaction temperature is -10 to 0 占 폚, and the second stage is 120 to 160 占 폚. If the reaction temperature is lower than -20 ° C, the purity of the synthesis decreases due to the aggregation and non-polymerization of the amine and BTC. If the reaction temperature is higher than 180 ° C, excessive amounts of tar and sludge are generated due to the formation of oligomers, have.

 In the present invention, the total content of the cyan compound, the nitro compound, and the iron in the meta-xylylenediamine is 0.3% or less.

As the cyan compound, 3-cyanobenzylamine represented by the following structural formula is typically used.

(3-cyanobenzylamine)

(3-cyanobenzylamine)

As the nitric acid compound, there is typically (3-nitrophenyl) methanamine of the following structural formula.

(3-nitrophenyl)methanamine

(3-nitrophenyl) methanamine

If the amount of the above-mentioned compound, nitric acid compound or iron in the above-mentioned meta-xylylenediamine is more than 0.3%, the chlorine impurity of the synthetic product is increased to cause a problem of haze.

Examples of the solvent usable in the reaction include benzene, toluene, ethylbenzene, chlorobenzene, monochlorobenzene, 1,2-dichlorobenzene, 1,2- dichlorobenzene, dichloromethane, 1-chloro-n-butane, 1-chloo-n-pentane and 1-chloro-n- (1-chloro-n-hexane), chloroform, carbon tetrachloride, n-pentane, n-hexane, n-heptane, is one or two types selected from the group consisting of n-octane, cyclohexane, cyclopentane, cyclooctane, and methyl cyclohexane. . In the present invention, it is most preferable to use monochlorobenzene.

The catalyst used is one or more selected from the group consisting of 4-Hydroxy-TEMPO, 4-nitrophenol and phenol.

The structural formula of the catalyst is as follows.

(4-hydroxy-TEMPO)

(4-hydroxy-TEMPO)

(4-nitrophenol)

(4-nitrophenol)

(phenol)

(phenol)

In the present invention, it is possible to produce high quality isocyanate compounds for optical materials having high purity and low yellowness index by using one or more of the above catalysts.

The amount of the catalyst used is preferably 0.05 to 1.5% by weight based on the weight of the amine. If the amount of the catalyst is less than 0.05% by weight, the reaction time during the reaction may increase and non-polymerization may occur. If the amount of the catalyst is more than 1.5% by weight, the purity may decrease due to the oligomer production and the increase of the tar content have.

(Meth) acrylate is synthesized by mixing the monomeric MXDI and the polymeric MXDI through the above steps. Thus, the monomeric MXDI is synthesized by purifying the monomeric MXDI Pure monomelic MXDI is obtained.

The total content of the chlorine compound and the cyanine compound in the methoxysilylene diisocyanate (MXDI) prepared through the synthesis and purification according to the present invention is 0.3% or less.

If the content of the chlorine compound, cyanine compound or salt in the MXDI exceeds 0.3%, there arises a problem that the prepared MXDI product itself and the haze of the formed lens are lowered when the lens is molded.

Examples of the chlorine compound include 3-chloromethyl-benzyl isocyanate and 3-aminomethylhydrochloride benzyl isocyanate represented by the following structural formulas.

(3-chloromethyl-benzyl isocyanate)(CBI)

(3-chloromethyl-benzyl isocyanate) (CBI)

(3-aminomethyl hydrochloride benzyl isocyanate)

(3-aminomethyl hydrochloride benzyl isocyanate)

As the cyanine compound, 3-cyanomethyl-benzyl isocyanate represented by the following structural formula is typically used.

(3-cyanomethyl-benzyl isocyanate)

(3-cyanomethyl-benzyl isocyanate)

The content (impurity content) of chlorine compounds, cyanine compounds, etc. in the methoxysilylene diisocyanate synthesized as described above is 0.3% or less.

In addition, the MXDI of the present invention prepared through the synthesis and purification processes as described above can be purified by distillation at a temperature of 60 to 150 ° C. and a vacuum pressure of 0.0001 to 100 mmHg to produce MXDI having a purity of 99% or more, Is less than or equal to 15.

 Example

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the following examples. However, the embodiments according to the present invention can be modified into various other forms, and the scope of the present invention should not be construed as being limited to the following embodiments. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art

Example 1

Step 1 reaction (cooling reaction):

114 parts by weight of bistric chloromethyl carbonate (BTC) and 384 parts by weight of monochlorobenzene as a solvent were charged in a flask, and 0.5 part by weight of 4-hydroxy-4-hydroxy-TEMPO as a catalyst in a separate beaker, And 60 parts by weight of benzene were completely dissolved and added to the flask, followed by cooling to -10 캜 with a cooling bath.

After 80 parts by weight of monochlorobenzene and meta-xylylenamine were mixed in the beaker, the mixture was slowly dropped over a period of about 3 hours at a temperature of -15 to -5 占 폚, The reaction mixture is further stirred at the low temperature.

Two-step reaction (heating reaction)

The flask was replaced with a heating oil bath and synthesis was carried out at 60 to 160 ° C for about 20 hours. Thereafter, additional bistrichlorocarbonate is further added to complete the reaction, followed by examination by gas chromatography (GC) to terminate and cool.

Three-stage distillation purification:

The synthesized isocyanate product was subjected to distillation purification under the conditions of 60 to 150 DEG C and 0.0001 to 100 mmHg to finally produce meta-xylylene diisocyanate (MXDI).

Example 2

Methoxysilylene diisocyanate was obtained in the same manner as in Example 1 except that 4-nitrophenol was used as the catalyst.

Example 3

The procedure of Example 1 was repeated except that phenol was used as the catalyst to obtain meta-xylylene diisocyanate.

Comparative Example 1

The procedure of Example 1 was repeated without using a catalyst.

Claims (5)

Synthesis and purification of meta-xylylene diamine and bis (trichloromethyl) carbonate at a temperature of -20 to 180 占 폚 in a solvent and a catalyst to prepare meta-xylylene diisocyanate , ≪ / RTI >
Wherein the catalyst is one or more selected from the group consisting of 4-Hydroxy-TEMPO, 4-nitrophenol and phenol. Way.
The method according to claim 1,
Wherein the total content of impurities cyan compound, nitro compound, and iron in the meta-xylylenediamine is 0.3% or less.
The method according to claim 1,
Wherein the total content of the chlorine compound and the cyanine compound in the prepared isocyanate compound for an optical material is 0.3% or less.
The method according to claim 1,
Wherein the prepared isocyanate compound for optical material is purified at 60 to 150 DEG C under 0.0001 to 100 mmHg to have a purity of 99% or more and an APHA value of 15 or less.
The method according to claim 1,
The solvent is selected from the group consisting of benzene, toluene, ethylbenzene, chlorobenzene, monochlorobenzene, 1,2-dichlorobenzene, dichloromethane, 1-chloro-n-butane, 1-chloo-n-pentane and 1-chloro-n- hexane, chloroform, carbon tetrachloride, n-pentane, n-hexane, n-heptane, n-octane, ) Is at least one selected from the group consisting of cyclohexane, cyclopentane, cyclooctane, and methyl cyclohexane. The isocyanate compound for optical material according to claim 1, Way.