Polythiol composition and optical resin material

Abstract

The present invention relates to the field of polymer materials, and in particular to a polythiol composition containing pentaerythritol tetra(3-mercaptopropionate) and a pentaerythritol tetra(3-mercaptopropionate) disulfide-substituted compound, and an optical resin material. The mass ratio of the pentaerythritol tetra(3-mercaptopropionate) disulfide-substituted compound to pentaerythritol tetra(3-mercaptopropionate) is 1:181 to 10,000. By controlling the specific proportion of the pentaerythritol tetra(3-mercaptopropionate) disulfide-substituted compound in the polythiol composition, the present invention effectively avoids gel polymerization inhibition, reduces the presence of active groups in resin lenses, and reduces the penetration of water and oxygen. This significantly reduces the deterioration and yellowing of resin lenses, reduces the occurrence of prism effects, and alleviates visual fatigue.

Description

[Technical Field]

[0001] The present invention belongs to the technical field of optical materials, and particularly relates to a polythiol composition and an optical resin material. [Background technology]

[0002] With the rapid development of the information society, the prevalence of myopia is increasing year by year, and is gradually becoming more prevalent among younger people. According to relevant statistics, the prevalence is 14.3% among 6-year-olds, 35.6% among elementary school students, 71.7% among middle school students, and 80.5% among high school students. Proper use of glasses and timely correction of vision can help prevent the continued deterioration of vision caused by fatigue of the human eye's lens.

[0003] Polythiol compounds are used in lenses with a refractive index of 1.56 to 1.61. The resulting lenses have excellent refractive index, toughness, and light transmittance characteristics, as well as cost-effectiveness, leading to a large market share. Current lens curing methods involve homogeneously mixing reactant materials, pouring them into a mold, and then heating them in an oven to react and solidify. The reaction rate increases as the temperature and degree of crosslinking increase. However, the reaction is carried out statically in the oven. The polythiol compounds have low reactivity and significant steric hindrance, which can lead to self-crosslinking of isocyanate groups and inhibition of gel polymerization. Furthermore, the viscosity of the reactant increases, resulting in partial curing, which prevents sufficient contact between active groups. The presence of uncrosslinked thiol and isocyanate groups during crosslinking increases the activity of these reactive groups, leading to deterioration and yellowing. Furthermore, the long shelf life of current eyeglasses—1 to 2 years—causes light and oxygen to denature the active groups during use, causing the lenses to yellow and lose transparency. In addition, polythiol compounds contain ester groups, which damage the molecular chains of lenses when secreted and penetrated by body oils and sweat, accelerating the deterioration rate. This phenomenon is particularly pronounced in rimless glasses, where the edges of the lenses generate heat and are not protected by a film layer, making them prone to oxidation and yellowing, causing a prismatic effect in the wearer, worsening visual fatigue and accelerating the deterioration of eyesight in young people. Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the current problems, the present invention provides a polythiol composition and an optical resin material. By using a specific proportion of pentaerythritol tetra(3-mercaptopropionate) disulfide substitution in the polythiol composition, the gel polymerization inhibition phenomenon can be effectively avoided, the presence of active groups in the resin lens and the penetration of water and oxygen can be reduced, and the deterioration and yellowing of the resin lens can be significantly reduced, the occurrence of prism effect can be reduced, and visual fatigue can be alleviated. [Means for solving the problem]

[0005] The technical solution of the present invention is as follows: A polythiol composition characterized by comprising pentaerythritol tetra(3-mercaptopropionate) and a pentaerythritol tetra(3-mercaptopropionate) disulfide substituted compound, wherein the mass ratio of the pentaerythritol tetra(3-mercaptopropionate) disulfide substituted compound to pentaerythritol tetra(3-mercaptopropionate) is 1:181 to 10,000. The structural formula of the pentaerythritol tetra(3-mercaptopropionate) disulfide substituted compound is shown in Formula 1.

[0006] [ka]

[0007] Preferably, the polythiol composition comprises 50 to 90 parts of a mixture of pentaerythritol tetra(3-mercaptopropionate) and pentaerythritol tetra(3-mercaptopropionate) disulfide substituted, 10 to 20 parts of pentaerythritol tris(3-mercaptopropionate), 2 to 15 parts of [2,2-bis(3-sulfonylpropionyloxymethyl)-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl] 3-sulfonylpropionate, and 50 to 145 parts of 2,3-dithio(2-mercapto)-1-propanethiol.

[0008] More preferably, the polythiol composition comprises 1 to 5 parts pentaerythritol bis(3-mercaptopropionate), 0 to 3 parts pentaerythritol-3-mercaptopropionate, and 0 to 5 parts [2-(hydroxymethyl)-2-(3-sulfonylpropionyloxymethyl)-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate.

[0009] An optical resin material made from the polythiol composition and an isocyanate.

[0010] When manufacturing the corresponding optical resin material, the practicality of the resulting optical material can be further improved by adding additives to the raw materials mentioned above. The raw materials may also contain additives such as catalysts, UV absorbers, release agents, blue agents, red agents, etc.

[0011] Preferably, the isocyanate is one or more selected from m-xylylene diisocyanate, cyclohexanedimethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and norbornane diisocyanate in any proportion.

[0012] Preferably, the raw material is cured to obtain the optical resin material.

[0013] The pentaerythritol tetra(3-mercaptopropionate) disulfide-substituted compound of the present invention (referred to as the "disulfide-substituted compound") contains six thiol groups compared to other polythiol compounds, significantly improving the relationship between the polythiol compound and isocyanate. This reduces steric hindrance and allows the polythiol's thiol groups to react with isocyanate to form active sites, thereby activating the polythiol's thiol groups and extending the molecular chain through reaction with isocyanate. This reduces the steric hindrance effect, resulting in a point-line-surface polymerization reaction, i.e., a uniform polymerization reaction. This avoids steric hindrance and gel inhibition, increases the crosslink density and uniformity of the resin network, reduces the presence of active groups and the intrusion of water and oxygen, and significantly reduces the progression of degradation. At the same time, because the structure of the disulfide-substituted compound is similar to that of polythiol compounds, lenses polymerized with isocyanate still exhibit excellent refractive index, toughness, and light transmittance properties. If too much disulfide substituent is added to the polythiol composition, the reaction will be too rapid during the degassing step, resulting in a viscosity that is too high to be poured into a mold, whereas adding too little will not be effective.

[0014] The following describes a method for synthesizing the pentaerythritol tetra(3-mercaptopropionate) disulfide-substituted product shown in Scheme 1, but the synthesis method is not limited to this. Specifically, the synthesis method involves placing pentaerythritol tetra(3-mercaptopropionate) and toluene in a water bath, stirring uniformly, adding an oxidizing agent, and preparing the product under the catalytic action of a neutral or alkaline reagent. After removing the solvent, the product is separated using a chromatography column to obtain the disulfide-substituted product.

[0015] Preferably, the mass ratio of pentaerythritol tetra(3-mercaptopropionate) to toluene is 1:5-10.

[0016] Preferably, the oxidizing agent is selected from one or more of air, oxygen, ozone, sulfur trioxide, hydrogen peroxide, metachloroperoxybenzoic acid, peroxybenzoic acid, and I2, in any proportion. The use of gaseous oxidizing agents results in a slower reaction rate and higher product selectivity. Liquid oxidizing agents have a faster reaction rate but tend to produce polymeric compounds, resulting in slightly lower selectivity. Therefore, gaseous oxidizing agents are more preferred.

[0017] Preferably, the molar ratio of oxidizing agent to pentaerythritol tetra(3-mercaptopropionate) is 10-30:1, more preferably 15-20:1. If the amount of oxidizing agent is too low, too little disulfide substitution occurs. If the amount of oxidizing agent is too high, excessive crosslinking occurs, leaving a small amount of gel-like material after solvent removal.

[0018] Preferably, the catalyst selected for the reaction is one of aqueous ammonia, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium bicarbonate, sodium carbonate, potassium carbonate, sodium dihydrogen phosphate, sodium phosphate, diethylamine, triethylamine, diethylamine, triethylamine, triethylenediamine, bisdimethylaminoethyl ether, bismorpholine diethyl ether, dimethylaminoethoxyethanol, N,N-dimethylcyclohexylamine, bis(2-dimethylaminoethyl)ether, N,N,N',N'-tetramethylalkylenediamine, N,N-dimethylbenzylamine, triethanolamine, DMEA, pyridine, N,N'-lutidine, or a plurality of catalysts in any proportion. More preferably, it is aqueous ammonia, triethylamine, or N,N-dimethylcyclohexylamine.

[0019] The molar ratio of the amount of catalyst to the amount of pentaerythritol tetra(3-mercaptopropionate) is 0.005 to 0.05: 1, more preferably 0.01 to 0.03: 1. If the amount of catalyst is too small, the amount of disulfide substitution will be small, and if the amount of catalyst is too large, excessive crosslinking will occur, and a small amount of gel-like material will remain after removing the solvent.

[0020] The reaction temperature is preferably 10 to 60° C., more preferably 20 to 40° C. If the reaction temperature is low, the substrate conversion rate will be too low, and if the reaction temperature is high, excessive crosslinking will occur, and when the solvent is removed, a slightly gel-like substance will appear.

[0021] Preferably, the height of the chromatography column is 40-80 cm, the diameter-to-height ratio of the column is 15-20:1, the optimum column height is 60 cm, the water absorbent is anhydrous sodium sulfate, and the eluent is petroleum ether and ethyl acetate in a mass ratio of 3-10:1, more preferably 5-7:1. [Effects of the Invention]

[0022] The polythiol composition and optical resin material provided by the present invention can effectively avoid gel polymerization inhibition and reduce the presence of active groups by controlling the specific ratio of pentaerythritol tetra(3-mercaptopropionate) disulfide substituents in the polythiol composition. The permeation of water and oxygen into the resin lens significantly reduces deterioration and yellowing of the resin lens, reduces the occurrence of prism effects, and alleviates visual fatigue. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a secondary mass spectrum of pentaerythritol tetra(3-mercaptopropionate) disulfide substitution. [Figure 2] 1 is an infrared spectrum of pentaerythritol tetra(3-mercaptopropionate) disulfide substituted. [Figure 3] 1H NMR spectrum of pentaerythritol tetra(3-mercaptopropionate) disulfide substitute. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention will be further described below with reference to examples, but these examples should not be construed as limiting the scope of the present invention. Those skilled in the art should understand that equivalent substitutions or corresponding improvements made to the technical features of the present invention are still within the scope of protection of the present invention. The transmittance and yellowness index (YI313) were measured using an UltraScan VIS spectrophotometer manufactured by HunterLab Company, USA. The operating temperature was 25-30°C, the light source was D65, and the spectral range was 360-780 nm. The following parts are based on mass percentages.

[0025] Example 1: A synthesis method for pentaerythritol tetra(3-mercaptopropionate) disulfide substitution: 20 g of pentaerythritol tetra(3-mercaptopropionate) and 100 g of toluene were dissolved by stirring in a 30°C water bath, then 0.13 g of triethylamine was added, and 0.82 mol of ozone was slowly passed through the solution. The reaction was incubated at 25°C for 48 hours. After removing the toluene under vacuum, a bright yellow liquid was obtained. A 60 cm high chromatography column with a diameter-to-height ratio of 20:1 was used, and the eluent was petroleum ether and ethyl acetate in a mass ratio of 6:1. The product was obtained by column chromatography. 1H NMR (400 MHz, CDCl3) δ 4.16 (s, 1H, OCH), 2.76-2.74 (m, 1H, SCH), 2.67-2.66 (m, 1H, O=CC -H), 1.60-1.64(m, 1H, SH).

[0026] All of the disulfide substitutions below refer to pentaerythritol tetra(3-mercaptopropionate) disulfide substitutions, as shown in Formula 1.

[0027] [ka]

[0028] (Example 2) Optical resin material: (1) Polythiol composition: 5.3 g of pentaerythritol tris(3-mercaptopropionate), 0.02 g of disulfide substitute, 40 g of pentaerythritol tetra(3-mercaptopropionate), 4.5 g of [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9 g of 2,3-dithio(2-mercapto)-1-propanethiol;

[0029] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of UV absorber 329, and 0.1 parts of a release agent (dibutyl phosphate) were mixed, thoroughly mixed, filtered through a 1 μm filter, and vacuum degassed at 30°C for 30 minutes. The mixture was poured into a mold, gradually heated from 30°C to 120°C within 8 hours, maintained at this temperature for 2 hours, and then cooled to 60°C over 3 hours to obtain an optical resin material. After coating, the resulting optical lens was left at 50°C and 95% RH for 200 hours to undergo accelerated aging testing, followed by performance testing.

[0030] (Example 3) Optical resin material: (1) Polythiol composition: 5.3 g of pentaerythritol tris(3-mercaptopropionate), 0.095 g of disulfide substitute, 40 g of pentaerythritol tetra(3-mercaptopropionate), 4.5 g of [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9 g of 2,3-dithio(2-mercapto)-1-propanethiol;

[0031] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of UV absorber 329, and 0.1 parts of a release agent (dibutyl phosphate) were mixed, thoroughly mixed, filtered through a 1 μm filter, and vacuum degassed at 30°C for 30 minutes. The mixture was poured into a mold, gradually heated from 30°C to 120°C within 8 hours, maintained at this temperature for 2 hours, and then cooled to 60°C over 3 hours to obtain an optical resin material. After coating, the resulting optical lens was left at 50°C and 95% RH for 200 hours to undergo accelerated aging testing, followed by performance testing.

[0032] (Example 4) Optical resin material: (1) Polythiol composition: 5.3 g of pentaerythritol tris(3-mercaptopropionate), 0.15 g of disulfide substitute, 40 g of pentaerythritol tetra(3-mercaptopropionate), 4.5 g of [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9 g of 2,3-dithio(2-mercapto)-1-propanethiol;

[0033] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of UV absorber 329, and 0.1 parts of a release agent (dibutyl phosphate) were mixed, thoroughly mixed, filtered through a 1 μm filter, and vacuum degassed at 30°C for 30 minutes. The mixture was poured into a mold, gradually heated from 30°C to 120°C within 8 hours, maintained at this temperature for 2 hours, and then cooled to 60°C over 3 hours to obtain an optical resin material. After coating, the resulting optical lens was left at 50°C and 95% RH for 200 hours to undergo accelerated aging testing, followed by performance testing.

[0034] (Example 5) Optical resin material: (1) Polythiol composition: 5.3 g of pentaerythritol tris(3-mercaptopropionate), 0.216 g of disulfide substitute, 40 g of pentaerythritol tetra(3-mercaptopropionate), 4.5 g of [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9 g of 2,3-dithio(2-mercapto)-1-propanethiol;

[0035] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of UV absorber 329, and 0.1 parts of a release agent (dibutyl phosphate) were mixed, thoroughly mixed, filtered through a 1 μm filter, and vacuum degassed at 30°C for 30 minutes. The mixture was poured into a mold, gradually heated from 30°C to 120°C within 8 hours, maintained at this temperature for 2 hours, and then cooled to 60°C over 3 hours to obtain an optical resin material. After coating, the resulting optical lens was left at 50°C and 95% RH for 200 hours to undergo accelerated aging testing, followed by performance testing.

[0036] (Example 6) Optical resin material: (1) Polythiol composition: 0.6g pentaerythritol bis(3-mercaptopropionate), 5.3g pentaerythritol tris(3-mercaptopropionate), 0.15g disulfide substituted, 1.7g [2-(hydroxymethyl)-2-(3-sulfonylpropionyloxymethyl)-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 40g pentaerythritol tetra(3-mercaptopropionate), 4.5g [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9g 2,3-dithio(2-mercapto)-1-propanethiol;

[0037] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of UV absorber 329, and 0.1 parts of a release agent (dibutyl phosphate) were mixed, thoroughly mixed, filtered through a 1 μm filter, and vacuum degassed at 30°C for 30 minutes. The mixture was poured into a mold, gradually heated from 30°C to 120°C within 8 hours, maintained at this temperature for 2 hours, and then cooled to 60°C over 3 hours to obtain an optical resin material. After coating, the resulting optical lens was left at 50°C and 95% RH for 200 hours to undergo accelerated aging testing, followed by performance testing.

[0038] (Comparative Example 1) Optical resin material: (1) Polythiol composition: 5.3 g of pentaerythritol tris(3-mercaptopropionate), 0.3 g of disulfide-substituted product, 40 g of pentaerythritol tetra(3-mercaptopropionate), 4.5 g of [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9 g of 2,3-dithio(2-mercapto)-1-propanethiol;

[0039] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of ultraviolet absorber 329, and 0.1 parts of a mold release agent (dibutyl phosphate) were mixed and thoroughly mixed, filtered through a 1 μm filter, and vacuum degassed for 30 minutes at 30° C. Then, when the mixture was poured into a mold, the tip of the gun was clogged with gel, making it impossible to pour the mixture into the mold.

[0040] (Comparative Example 2) Optical resin material: (1) Polythiol composition: 5.3 g of pentaerythritol tris(3-mercaptopropionate), 40 g of pentaerythritol tetra(3-mercaptopropionate), 4.5 g of [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9 g of 2,3-dithio(2-mercapto)-1-propanethiol;

[0041] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of UV absorber 329, and 0.1 parts of a release agent (dibutyl phosphate) were mixed, thoroughly mixed, filtered through a 1 μm filter, and vacuum degassed at 30°C for 30 minutes. The mixture was poured into a mold, gradually heated from 30°C to 120°C within 8 hours, maintained at this temperature for 2 hours, and then cooled to 60°C over 3 hours to obtain an optical resin material. After coating, the resulting optical lens was left at 50°C and 95% RH for 200 hours to undergo accelerated aging testing, followed by performance testing.

[0042] (Comparative Example 3) Optical resin material: (1) Polythiol composition: 5.3 g of pentaerythritol tris(3-mercaptopropionate), 40 g of pentaerythritol tetra(3-mercaptopropionate), 4.5 g of [2,2-bis(3-sulfonylpropionyloxymethyl)]-3-[3-(3-sulfonylpropionylsulfonyl)propionyloxy]propyl]3-sulfonylpropionate, 51.9 g of 2,3-dithio(2-mercapto)-1-propanethiol;

[0043] (2) 55 parts of norbornane diisocyanate, 45 parts of a polythiol composition, 0.05 parts of dibutyltin dichloride, 0.6 parts of UV absorber 329, and 0.1 parts of a release agent (dibutyl phosphate) were mixed and thoroughly mixed. The mixture was filtered through a 1 μm filter and vacuum degassed at 30°C for 30 minutes. The mixture was then poured into a mold, gradually heated from 30°C to 120°C within 8 hours, maintained at this temperature for 2 hours, and then cooled to 60°C over 3 hours to obtain an optical resin material. After coating, the resulting optical lens was left at 50°C and 95% RH for 200 hours, subjected to accelerated aging verification, and then subjected to performance testing. (Test Example)

[0044] [Table 1]

[0045] The above mass ratio is the mass ratio of pentaerythritol tetra(3-mercaptopropionate) disulfide substitute to pentaerythritol tetra(3-mercaptopropionate).

[0046] From the data in Table 1 above, it can be seen that the content of the pentaerythritol tetra(3-mercaptopropionate) disulfide substituted compound in Comparative Example 1 was too high, resulting in high viscosity. When poured into a mold, gelation occurred at the tip of the gun, making it impossible to pour. After aging, the front light transmittance of the products in Examples 2-4 of the present invention was higher than that of the products in Comparative Examples 2-3, but their yellowness index was significantly lower than that of the comparative examples. Furthermore, the edge light transmittance of the products in Examples 2-4 of the present invention was even higher than that of the products in Comparative Examples 2-3, but their yellowness index was significantly lower than that of the products in Comparative Examples 2-3. Through verification of the above test examples, it was found that the use of a specific proportion of the pentaerythritol tetra(3-mercaptopropionate) disulfide substituted compound in the polythiol composition effectively avoided gel polymerization inhibition, reduced the presence of active groups in the resin lens and the penetration of water and oxygen, significantly reduced deterioration and yellowing of the resin lens, reduced the occurrence of prism effects, and alleviated visual fatigue. It also extended the service life of eyeglasses.

Claims

1. A polythiol composition comprising an isocyanate, The polythiol composition comprises pentaerythritol tetra(3-mercaptopropionate) and pentaerythritol tetra(3-mercaptopropionate) disulfide substituted products. The structural formula of the aforementioned pentaerythritol tetra(3-mercaptopropionate) disulfide substitution is shown in Formula 1. 【Chemistry 1】 The mass ratio of the pentaerythritol tetra(3-mercaptopropionate) disulfide substitution to pentaerythritol tetra(3-mercaptopropionate) is 1:181 to 1:10000. An optical resin material characterized by the following features.

2. The optical resin material according to claim 1, characterized in that the polythiol composition comprises 50 to 90 parts by mass of a mixture of pentaerythritol tetra(3-mercaptopropionate) and a pentaerythritol tetra(3-mercaptopropionate) disulfide substituted product, 10 to 20 parts by mass of pentaerythritol tris(3-mercaptopropionate), 2 to 15 parts by mass of 3-sulfanylpropanoic acid [2,2-bis(3-sulfanylpropanoyloxymethyl)-3-[3-(3-sulfanylpropanoylsulfanyl)propanoyloxy]propyl] ester, and 50 to 145 parts by mass of 2,3-bis(2-mercaptoethylthio)-1-propanthol.

3. The optical resin material according to claim 2, characterized in that the polythiol composition further comprises 1 to 5 parts by mass of pentaerythritol bis(3-mercaptopropionate), 0 to 3 parts by mass of pentaerythritol-3-mercaptopropionate, and 0 to 5 parts by mass of 3-sulfanylpropanoic acid [2-(hydroxymethyl)-2-(3-sulfanylpropanoyloxymethyl)-3-[3-(3-sulfanylpropanoylsulfanyl)propanoyloxy]propyl] ester.

4. The optical resin material according to claim 1, characterized in that the isocyanate is any one of metaxylylene diisocyanate, cyclohexanedimethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, norbornane diisocyanate, or a combination of any number thereof in any proportion.

5. The optical resin material according to claim 1, characterized in that it is obtained by curing a mixture of the polythiol composition and the isocyanate as raw materials.

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