JP4844136B2 - Resin composition - Google Patents

Description

  The present invention relates to a method of manufacturing an optical material such as a plastic lens, a prism, an optical fiber, an information recording base, and a filter, and in particular, a plastic lens for spectacles.

In recent years, plastic materials have been widely used in various optical materials, particularly eyeglass lenses, because they are light and tough and easy to dye. Performances particularly required for optical materials, particularly spectacle lenses, are low specific gravity, high transparency and low yellowness, high refractive index and high Abbe number as optical performance, high heat resistance, and high strength. A high refractive index enables the lens to be thinned, and a high Abbe number reduces the chromatic aberration of the lens. High strength facilitates secondary processing and is important from the viewpoint of safety and the like. An episulfide compound can be used as a method for simultaneously realizing a high refractive index, a high Abbe number, and a high heat resistance in optical performance. However, it has been a problem to increase the strength of optical materials made of the compound. For this reason, examination about improvement of various strengths, such as tensile strength and impact resistance, is performed by adding a thiol compound and an isocyanate compound in addition to an episulfide compound (refer to patent documents 1 and 2). These optical materials are usually produced by a cast polymerization method. Conventionally, the mold is made of only metal or glass, or a combination of glass or metallic mold and resin gasket. However, the use of a resin gasket not only costs the resin gasket for one molded product, but also has a problem that the used resin gasket after molding can hardly be recycled. Industrial waste increased accordingly. As a method for solving these problems, a method of polymerizing using an adhesive tape in which an adhesive material is applied to the outer peripheral portions of two opposing molds instead of a resin gasket has been proposed (see Patent Document 3). In recent years, many lens manufacturers have adopted it industrially. However, in the case where an thiol compound and an isocyanate compound are added to an episulfide compound, when the adhesive tape coated with the adhesive material is cured using a mold wound around the outer periphery of two opposing molds, the adhesive material The components are eluted, and the resulting optical material has the disadvantage that white turbidity is generated, which is not practical for optical materials that require high transparency.
JP 2001-131257 A JP 2001-330701 A Japanese Patent Laid-Open No. 10-146849

The present invention has been made based on such circumstances, and is obtained by polymerizing and curing an episulfide compound to which a thiol compound and an isocyanate compound are added, using a mold using an adhesive tape coated with an adhesive material. Even if it makes it, it is to develop a technique for producing an optical material industrially easily without causing cloudiness.

As a result of intensive studies to solve these problems, the present inventors have obtained a compound (b) represented by the following formula (2):

チオール基を１分子中に２個以上有する（ｃ）化合物を予備重合させることにより、得られる光学材料が、粘着材で塗布された粘着テープを対向する２枚のモールドの外周部を巻きつけた型を使用しても、白濁を生じないことを見出し、本発明に至った。

By prepolymerizing the compound (c) having two or more thiol groups in one molecule, the obtained optical material is wound around the outer periphery of two molds facing the adhesive tape coated with the adhesive. It was found that even when a mold was used, white turbidity did not occur, and the present invention was reached.

According to the present invention, even if a mold having a pressure-sensitive adhesive tape coated with a pressure-sensitive adhesive material is wound around the outer periphery of the mold, by performing prepolymerization, it is achieved that no white turbidity occurs, and industrially easy optical It has become possible to provide a method for manufacturing materials.

As the episulfide compound used in the present invention, an aliphatic episulfide compound is selected in order to simultaneously exhibit a high refractive index and a high Abbe number, and in particular, it has two or more episulfide groups in order to exhibit high heat resistance. The compound was selected. As a result of further investigation, the effect of the present invention was very remarkable in the specific compound (a) represented by the following formula (1).

Specific examples of the compound (a) include bis (β-epithiopropyl) sulfide, bis (β-epithiopropyl) disulfide, bis (β-epithiopropyl) trisulfide, and bis (β-epithiopropylthio). Methane, 1,2-bis (β-epithiopropylthio) ethane, 1,3-bis (β-epithiopropylthio) propane, 1,2-bis (β-epithiopropylthio) propane, 1,4 -Episulfides such as bis (β-epithiopropylthio) butane and bis (β-epithiopropylthioethyl) sulfide. (A) The compounds may be used alone or in combination of two or more. Among them, preferred specific examples are bis (β-epithiopropyl) sulfide and / or bis (β-epithiopropyl) disulfide, and the most preferred specific example is bis (β-epithiopropyl) sulfide.

As the isocyanate compound, an isocyanate compound having an aromatic ring was selected in order to maintain a high refractive index, and in particular, a compound having two or more isocyanate groups was selected in order to exhibit high heat resistance. As a result of further investigation, the effect of the present invention was very remarkable in the specific compound (b) represented by the following formula (2).

Specific examples of the compound (b) include polyisocyanates such as m-xylylene diisocyanate, p-xylylene diisocyanate, m-tetramethyl xylylene diisocyanate, and p-tetramethyl xylylene diisocyanate. (B) The compounds may be used alone or in combination of two or more. Among these, preferred specific examples are m-xylylene diisocyanate and / or m-tetramethylxylylene diisocyanate which are industrially easily available, and the most preferred specific example is m-tetramethyl which exhibits high heat resistance. Xylylene diisocyanate.
As a thiol compound, a thiol compound having at least one sulfide bond in one molecule is selected in order to maintain a high refractive index, and in particular, having at least two thiol groups in one molecule to exhibit high heat resistance. The compound was selected. That is, the effect of the present invention was remarkably exhibited in the specific compound (c) having one or more sulfide bonds in one molecule and two or more thiol groups in one molecule.

Specific examples of the compound (c) include bis (2-mercaptoethyl) sulfide, bis (2,3-dimercaptopropyl) sulfide, 1,2-bis (2-mercaptoethylthio) ethane, 2- (2- Mercaptoethylthio) -1,3-dimercaptopropane, 1,2-bis (2-mercaptoethylthio) -3-mercaptopropane, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 2, 4-bis (mercaptomethyl) -1,5-dimercapto-3-thiapentane, 4,8-bis (mercaptomethyl) -1,11-dimercapto-3,6,9-trithiaundecane, 4,7-bis ( Mercaptomethyl) -1,11-dimercapto-3,6,9-trithiaundecane, 5,7-bis (mercaptomethyl) -1,11-dimethyl Capto-3,6,9-trithiaundecane, 1,2,7-trimercapto-4,6-dithiaheptane, 1,2,9-trimercapto-4,6,8-trithianonane, 1,2,8, 9-tetramercapto-4,6-dithianonane, 1,2,10,11-tetramercapto-4,6,8-trithiaundecane, 1,2,12,13-tetramercapto-4,6,8,10 -Tetrathiatridecane, tetrakis (4-mercapto-2-thiabutyl) methane, tetrakis (7-mercapto-2,5-dithiaheptyl) methane, 1,5-dimercapto-3-mercaptomethylthio-2,4-dithiapentane, 3, , 7-bis (mercaptomethylthio) -1,9-dimercapto-2,4,6,8-tetrathianonane, 1,1,3,3-tetrakis (mercapto) Methylthio) propane, 2,5-bis (mercaptomethyl) -1,4-dithiane, 2,5-bis (2-mercaptoethyl) -1,4-dithiane, 2,5-bis (mercaptomethyl) -1- Polythiols such as thiane, 2,5-bis (2-mercaptoethyl) -1-thiane, bis (4-mercaptophenyl) sulfide, bis (4-mercaptomethylphenyl) sulfide, 3,4-thiophenedithiol, and the like And thiols such as oligomers such as dimers to 20-mers. (C) The compounds may be used alone or in combination of two or more. Among these, preferred specific examples are bis (2-mercaptoethyl) sulfide and / or 2,5-bis (mercaptomethyl) -1,4-dithiane, and the most preferred specific examples are easily available industrially. Bis (2-mercaptoethyl) sulfide.

In the composition for optical materials of the present invention, the total amount of the compound (b) and the compound (c) relative to the amount of the compound (a) varies depending on the optical properties, strength, and heat resistance of the cured product obtained depending on the type of these compounds. Therefore, although it is not generally determined, the total amount of (b) compound and (c) compound is usually 50 to 10 parts by weight, preferably (a) compounds 60 to 85, based on 50 to 90 parts by weight of (a) compound. The total amount of the compound (b) and the compound (c) is 40 to 15 parts by weight, more preferably the total amount of the compound (b) and the compound (c) with respect to 65 to 80 parts by weight of the compound (a). 35 to 20 parts by weight. (A) When the addition amount of the compound is less than 50 parts by weight, the heat resistance may be lowered, and when it exceeds 90 parts by weight, the strength improvement effect may not be obtained.

Furthermore, regarding the ratio of the NCO group of the compound (b) to the SH group of the compound (c), preferably SH group / NCO group = 1.0 to 2.5, more preferably SH group / NCO group = 1. .25 to 2.25, more preferably SH group / NCO group = 1.5 to 2.0. If the ratio is less than 1.0, the cured product may be yellow, and if it exceeds 2.5, the heat resistance may be reduced.

The method for producing an optical material of the present invention is characterized by preliminarily polymerizing the compound (b) and the compound (c). In this preliminary reaction, the thiol group of (b) compound and the isocyanate group of (c) compound undergo an addition reaction to form a thiourethane bond. When an optical material is manufactured without pre-polymerization using an adhesive tape coated with an adhesive material wrapped around the outer periphery of two opposing molds, the adhesive material component elutes and becomes cloudy. However, white turbidity of the obtained optical material is suppressed by prepolymerizing the compound (b) and the compound (c). The prepolymerization is preferably performed at −10 to 120 ° C. for 0.1 to 240 hours, more preferably −5 to 100 ° C. for 0.1 to 120 hours, and particularly preferably 0 to 80 ° C. for 0.1 to 60 hours. is there. The prepolymerization may be carried out in any atmosphere such as air, presence of a gas such as nitrogen or oxygen, sealing under normal pressure or pressure reduction, or pressure reduction.

In the prepolymerization, some or all of various additives such as a compound capable of reacting with some or all of the composition components used as a performance improver and an ultraviolet absorber may be added. In addition, it is preferable to measure this prepolymerization by liquid chromatography and / or viscosity and / or specific gravity and / or refractive index and / or IR in order to control the degree of reaction progress and produce a certain optical material. Among them, the technique using IR is more preferable because it is simple, and the use of FT-IR is most preferable because the measurement accuracy increases.

In order to increase the effect of the prepolymerization, the (b) compound and the (c) compound are effectively reacted to consume the isocyanate group of the (b) compound. (B) When the consumption of isocyanate groups in the compound is less than 50%, the optical material becomes cloudy, which is not preferable. Preferably, the isocyanate group of the compound (b) is consumed by 50% or more, more preferably 70% or more.

In the prepolymerization, the compound (a) may be added. The addition amount is not generally determined by setting the reaction temperature and reaction time, but is usually 0 to 80 parts by weight with respect to the total amount of (b) compound and (c) compound of 40 to 15 parts by weight. The amount is preferably 0 to 40 parts by weight. When the compound (a) is not added, the viscosity of the prepolymerized solution becomes high and handling is difficult, and when the compound (a) exceeds 40 parts by weight, the thiourethanization reaction is delayed.

In the prepolymerization, a catalyst may be used. When a catalyst is used, any type can be used as long as it contributes to the reaction between the compound (b) and the compound (c), but a catalyst that can be used for polymerization and curing is preferable. Specific examples include amines, Lewis acids, quaternary ammonium salts, quaternary phosphonium salts, tertiary sulfonium salts, and secondary iodonium salts. Of these, quaternary phosphonium salts are particularly preferred. The weight when the catalyst is used varies depending on the reaction temperature, reaction time, and the ratio of the (b) compound and the (c) compound, and thus cannot be generally determined. Usually, the weight of the (b) compound and the (c) compound is not determined. It is 0.00001 weight part-5.0 weight part with respect to a total amount of 40-15 weight part, Preferably it is 0.0001 weight part-2.0 weight part.

In the prepolymerization, a polymerization regulator may be used. When a polymerization regulator is used, it may be of any kind as long as it controls the catalytic effect, but is preferably a compound that can be used in polymerization and curing. Examples of the polymerization regulator include halides of Groups 13 to 16 in the long-term periodic table. Among these, preferred are halides of silicon, germanium, tin and antimony, and more preferred are chlorides of germanium, tin and antimony having an alkyl group. More preferred are specifically dibutyltin dichloride, butyltin trichloride, dioctyltin dichloride, octyltin trichloride, dibutyldichlorogermanium, butyltrichlorogermanium, diphenyldichlorogermanium, phenyltrichlorogermanium, triphenylantimony dichloride, most preferred A specific example is dibutyltin dichloride. The polymerization regulator may be used alone or in combination of two or more. The weight when using the polymerization regulator varies depending on the reaction temperature, reaction time, and the ratio of the (b) compound and the (c) compound, and thus cannot be determined unconditionally, but usually the (b) compound and (c) It is 0.00001 weight part-5.0 weight part with respect to 40-15 weight part of total amounts of a compound, Preferably it is 0.0001 weight part-2.0 weight part.

In mixing, the set temperature, the time required for this, and the like may basically be the conditions under which each component is sufficiently mixed.

As the polymerization catalyst used in the present invention, a thermosetting catalyst is mainly used, but a photocurable catalyst or other active energy ray catalyst may be used. As the polymerization catalyst, an ionic catalyst having an effect on both the polymerization of the episulfide compound and the polyaddition of the isocyanate compound and the thiol compound is selected, and in particular, the viscosity at the time of composition preparation is high and the handling is good. In view of the above and high heat resistance, the effect of the present invention was remarkably exhibited in the compound (d) which is an onium salt.

The compound (d) is preferably a quaternary ammonium salt, a quaternary phosphonium salt, a tertiary sulfonium salt, or a secondary iodonium salt. Among them, a quaternary ammonium salt and a quaternary ammonium salt having good compatibility with the composition are preferable. A quaternary phosphonium salt is more preferable, and a quaternary phosphonium salt is more preferable.

More specific examples of the compound (d) include quaternary ammonium salts such as tetra-n-butylammonium bromide, triethylbenzylammonium chloride, cetyldimethylbenzylammonium chloride, 1-n-dodecylpyridinium chloride, tetra-n- Quaternary phosphonium salts such as butylphosphonium bromide and tetraphenylphosphonium bromide are exemplified. Among these, further preferred specific examples are triethylbenzylammonium chloride and / or tetra-n-butylphosphonium bromide, and the most preferred specific example is tetra-n-butylphosphonium bromide.

The amount of the compound (d) added varies depending on the components of the composition, the mixing ratio, and the polymerization curing method, but is not generally determined, but is usually the sum of the compounds (a), (b) and (c). 0.0001 to 10 parts by weight, preferably 0.001 to 5 parts by weight, more preferably 0.01 to 1 part by weight, and most preferably 0.01 to 100 parts by weight Part by weight to 0.5 part by weight is used. (D) If the amount of the compound is more than 10 parts by weight, the refractive index and heat resistance of the cured product may be lowered and coloring may occur. On the other hand, if it is less than 0.0001 part by weight, it may not be cured sufficiently and heat resistance may be insufficient.

In the resin composition of the present invention, an episulfide compound other than the compound (a), an iso (thio) cyanate compound other than the compound (b), a thiol compound other than the compound (c), and a polymerization catalyst other than the compound (d) are added. It is an effective means to adjust various physical properties of the cured product. The addition amount of these compounds is usually 0.0001 to 5 parts by weight with respect to 100 parts by weight of the total of the (a) compound, (b) compound and (c) compound.

When the composition for optical material is polymerized and cured, a polymerization regulator can be added as necessary for the purpose of extending the pot life or dispersing the polymerization heat. Examples of the polymerization regulator include halides of Groups 13 to 16 in the long-term periodic table. Among these, preferred are halides of silicon, germanium, tin and antimony, and more preferred are chlorides of germanium, tin and antimony having an alkyl group. More preferred are specifically dibutyltin dichloride, butyltin trichloride, dioctyltin dichloride, octyltin trichloride, dibutyldichlorogermanium, butyltrichlorogermanium, diphenyldichlorogermanium, phenyltrichlorogermanium, triphenylantimony dichloride, most preferred A specific example is dibutyltin dichloride. The polymerization regulator may be used alone or in combination of two or more.

The addition amount of a polymerization regulator is 0.0001-5.0 weight part with respect to a total of 100 weight part of (a) compound, (b) compound, and (c) compound, Preferably it is 0.0005-3. 0.0 part by weight, more preferably 0.001 to 2.0 parts by weight.

Moreover, adding an inorganic compound containing a sulfur atom to form a composition is also an effective means for adjusting the optical properties of the cured product. Specific examples of inorganic compounds containing a sulfur atom include sulfur, hydrogen sulfide, carbon disulfide, selenocarbon sulfide, ammonium sulfide, sulfur dioxide, sulfur trioxide, and other sulfur oxides, thiocarbonates, sulfuric acid and salts thereof, sulfides. Hydrogen salt, sulfite, hyposulfite, persulfate, thiocyanate, thiosulfate, sulfur dichloride, thionyl chloride, thiophosgene and other halides, boron sulfide, nitrogen sulfide, silicon sulfide, phosphorus sulfide, arsenic sulfide, Examples thereof include selenium sulfide, metal sulfide, and metal hydrosulfide. These may be used alone or in combination of two or more. Of these, preferred examples are sulfur or selenium sulfide, and most preferred is sulfur. The addition amount is usually 0.0001 to 5 parts by weight with respect to 100 parts by weight of the total of the compound (a), the compound (b) and the compound (c).

Furthermore, addition of an epoxy compound to form a composition is also an effective means for improving the uniformity of the cured product. Specific examples of epoxy compounds include phenolic epoxy compounds produced by condensation of aromatic hydroxy compounds such as phenol and bisphenol A and epihalohydrin, alcoholic epoxy compounds produced by condensation of alcohol compounds and epihalohydrin, carboxylic acid compounds, and the like. Glycidyl ester epoxy compound produced by condensation of epihalohydrin, amine epoxy compound produced by condensation of amine and epihalohydrin, epoxy compound produced by oxidative epoxidation of unsaturated compound, alcohol, phenol compound and diisocyanate and glycidol, etc. Urethane epoxy compounds produced from the above, and compounds in which part or all of the thiirane ring of the episulfide compound is substituted with an epoxy ring It can be. Among these, a phenolic epoxy compound is preferable, and diglycidyl ether of bisphenol A is most preferable. The addition amount is usually 0.0001 to 5 parts by weight with respect to 100 parts by weight of the total of the compound (a), the compound (b) and the compound (c).

Further, in order to improve the dyeability of the cured product obtained by polymerizing the composition of the present invention, as a dyeability-improving component, carboxylic acid, mercaptocarboxylic acid, hydroxycarboxylic acid, amide, 1,3-diketone, 1,3- It can also be used in combination with dicarboxylic acid, 3-ketocarboxylic acid and its esters, mercapto alcohols, and compounds having an unsaturated group. The addition amount of these compounds is usually 0.0001 to 5 parts by weight with respect to 100 parts by weight of the total of the (a) compound, (b) compound and (c) compound.

The cured product of the present invention has (a) a compound having two or more functional groups capable of reacting with the compound or (a) one functional group capable of reacting with the compound and one or more other functional groups capable of homopolymerization. It can also be produced by curing polymerization with a polymerizable compound such as a compound. Examples of these compounds include known compounds having a thiirane ring, polyvalent carboxylic acid anhydrides, compounds having an unsaturated group, etc., and these may be used alone or in combination of two or more.

Furthermore, when using a compound having an unsaturated group, it is a preferable method to use a radical polymerization initiator as a polymerization accelerator. The radical polymerization initiator is not particularly limited as long as it generates radicals by heating or ultraviolet rays or electron beams, and is a known thermal polymerization catalyst such as known peroxides or azo compounds, or a known one such as benzophenone or benzoin benzoin methyl ether. A photopolymerization catalyst is mentioned. These may be used alone or in combination of two or more. The blending amount of the radical polymerization initiator varies depending on the components of the composition and the polymerization curing method, and thus cannot be determined at a glance. Usually, the total of 100 weights of the (a) compound, (b) compound and (c) compound is used. The amount is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on parts.

Furthermore, the composition according to the present invention may contain not only these but also the oligomers of the compound (a), solvents and acids used in the synthesis, unreacted raw materials, and by-products as long as they do not become a problem.

In addition, when an optical material is obtained by polymerizing and curing the composition of the present invention, additives such as known antioxidants, ultraviolet absorbers, yellowing inhibitors, bluing agents, pigments, and the like are added to obtain the material. Of course, the practicality can be further improved. When the composition of the present invention is easily peeled off from the mold during polymerization, a known external and / or internal adhesion improver may be used or added to control and improve the adhesion between the obtained cured product and the mold. Is also possible. Examples of the adhesion improver include known silane coupling agents and titanate compounds, and these may be used alone or in combination of two or more. The addition amount is usually 0.0001 to 5 parts by weight with respect to 100 parts by weight of the total of the compound (a), the compound (b) and the compound (c). Conversely, when the composition of the present invention is difficult to peel off from the mold after polymerization, a known external and / or internal mold release agent may be used or added to improve the mold releasability from the mold of the resulting cured product. Is also possible. Release agents include fluorine-based nonionic surfactants, silicon-based nonionic surfactants, alkyl quaternary ammonium salts, phosphate esters, acidic phosphate esters, oxyalkylene-type acidic phosphate esters, alkali metal salts of acidic phosphate esters, oxy Alkali metal salts of acidic phosphates, metal salts of higher fatty acids, higher fatty acid esters, paraffins, waxes, higher aliphatic amides, higher aliphatic alcohols, polysiloxanes, aliphatic amine ethylene oxide adducts, etc. May be used alone or in combination of two or more. The addition amount is usually 0.0001 to 5 parts by weight with respect to 100 parts by weight of the total of the compound (a), the compound (b) and the compound (c).

The method for producing an optical material by polymerizing and curing the composition of the present invention will be described in detail as follows. Additives such as the above-mentioned composition components, antioxidants, ultraviolet absorbers, polymerization catalysts, radical polymerization initiators, adhesion improvers, mold release agents, etc., all mixed together in the same container under stirring, Each raw material may be added and mixed in stages, or several components may be mixed separately and then remixed in the same container. Each raw material and auxiliary raw material may be mixed in any order.

In the present invention, a degassing treatment is performed on the resin composition in advance, which may achieve a high degree of transparency of the optical material. The deaeration treatment is performed under reduced pressure before, during or after mixing the compound capable of reacting with some or all of the composition components, the polymerization catalyst, and the additive. Preferably, it is performed under reduced pressure during or after mixing. The treatment conditions are 0 to 100 ° C. under reduced pressure of 0.001 to 50 torr for 1 minute to 24 hours. The degree of decompression is preferably 0.005 to 25 torr, more preferably 0.01 to 10 torr, and the degree of decompression may be varied within these ranges. The deaeration time is preferably 5 minutes to 18 hours, more preferably 10 minutes to 12 hours. The temperature at the time of deaeration is preferably 5 ° C. to 80 ° C., more preferably 10 ° C. to 60 ° C., and the temperature may be varied within these ranges. In the deaeration process, renewing the interface of the resin composition by stirring, blowing of gas, vibration by ultrasonic waves, or the like is a preferable operation for enhancing the deaeration effect. The components removed by the degassing treatment are mainly dissolved gases such as hydrogen sulfide and low-boiling substances such as low molecular weight thiols, but the type is not particularly limited as long as the effects of the present invention are exhibited. .

Furthermore, filtering and purifying impurities and the like with a filter having a pore size of about 0.05 to 10 μm from these resin compositions and / or raw materials before mixing further enhances the quality of the optical material of the present invention. Is also preferable.

The resin composition thus obtained is injected into a glass or metal mold and gasket mold, polymerized and cured by irradiation with active energy rays such as heating or ultraviolet rays, and then removed from the mold. Is done. Preferably, it is polymerized and cured by heating. In this case, the curing time is 0.1 to 200 hours, usually 1 to 100 hours, and the curing temperature is −10 to 160 ° C., usually −10 to 140 ° C. The polymerization can be carried out by holding at a predetermined polymerization temperature for a predetermined time, raising the temperature from 0.1 ° C. to 100 ° C./h, lowering the temperature from 0.1 ° C. to 100 ° C./h, and a combination thereof. Further, after the polymerization is completed, annealing the cured product at a temperature of 50 to 150 ° C. for about 10 minutes to 5 hours is a preferable treatment for removing the distortion of the optical material of the present invention. Furthermore, surface treatments such as dyeing, hard coating, impact resistant coating, antireflection and imparting antifogging properties can be performed as necessary.

There are silicon, acrylic, epoxy, rubber, etc. as the adhesive material of the tape used when winding the adhesive tape coated with the adhesive material around the outer periphery of two opposing molds. Depending on the material, there are problems that air bubbles are mixed in, liquid leaks, adhesive material remains, the optical resin becomes cloudy, and the releasability deteriorates. Of these, acrylic adhesives and silicon adhesives are preferable, and silicon adhesives are more preferable.

Furthermore, as a base material used for a tape, polyester, polycarbonate, polyphenylene sulfide and the like such as polyethylene, polypropylene and polyethylene terephthalate are generally mentioned, but polyester is particularly preferable from the viewpoint of strength and price.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, evaluation of the cloudiness of the obtained hardened | cured material was performed with the following method.

The cloudiness was evaluated by visually observing the cured product with light from a fluorescent lamp in a dark room. A sample without white turbidity was marked with ◯ and a sample with white turbidity was marked with ×.

(B) FTIR-4100 (manufactured by JASCO) was used for calculation of the isocyanate consumption of the compound, and a KBr crystal plate was used, and the spectrum of the prepolymer solution (N = C = O absorption due to stretching vibration: 2250 cm ⁻¹ And absorption by CH2 stretching vibration: 2918 cm ⁻¹ ) was used. Based on the intensity ratio of (N = C = O absorbance of stretching vibration) / (absorbance of CH2 stretching vibration) at the start of pre-polymerization based on the above spectrum, the above-mentioned intensity ratio of the pre-polymerized solution was measured, The remaining amount of isocyanate groups was calculated.

<Example 1>
(B) 9.5 parts by weight of m-tetramethylxylylene diisocyanate as the compound, (c) 10.5 parts by weight of bis (2-mercaptoethyl) sulfide as the compound, and (d) 0.001% by weight of tetrabutylphosphonium bromide as the compound Parts were mixed and prepolymerized at 15 ° C. for 4 hours, and it was confirmed by FT-IR that the isocyanate group consumption of the compound (b) was 70%. 80 parts by weight of bis (β-epithiopropyl) sulfide as the compound (a) is added to the prepolymerized solution, and 0.1 part by weight of tetrabutylphosphonium bromide is mixed as the compound (d) to obtain a uniform resin composition. did. The obtained resin composition was degassed and filtered through a 0.5 μm PTFE membrane filter. Next, using two 83 mmφ glass molds facing this composition, the adhesive tape (# 6263-50, manufactured by SLIONTEC) with a silicon-based adhesive applied to the outer periphery so that the edge thickness is 10 mm. It was poured into a rolled mold (FIG. 1), heated in an oven at 30 ° C. for 10 hours, from 30 ° C. to 100 ° C. over 10 hours, and finally polymerized and cured at 100 ° C. for 1 hour. The cured product was allowed to cool to room temperature, released from the mold, and then annealed at 110 ° C. for 1 hour. The obtained cured product had not only excellent optical properties and physical properties, but also a good surface state and color tone, and good heat resistance, optical distortion and transparency. The results of cloudiness are shown in Table 1.

<Example 2>
(A) 20 parts by weight of bis (β-epithiopropyl) sulfide as the compound, (b) 9.5 parts by weight of m-tetramethylxylylene diisocyanate as the compound, and (c) bis (2-mercaptoethyl) sulfide 10 as the compound .5 parts by weight, (d) 0.005 part by weight of tetrabutylphosphonium bromide as a compound was mixed and prepolymerized at 15 ° C. for 20 hours, and (b) the consumption of isocyanate groups in the compound was 70%. This was confirmed by FT-IR. 60 parts by weight of bis (β-epithiopropyl) sulfide as a compound (a) is added to the prepolymerized solution, and 0.1 part by weight of tetrabutylphosphonium bromide is mixed as a compound (d) to obtain a uniform resin composition. did. Hereinafter, after the degassing treatment of the resin composition, the same procedure as in Example 1 was performed. The obtained cured product had not only excellent optical properties and physical properties, but also a good surface state and color tone, and good heat resistance, optical distortion and transparency. The results of cloudiness are shown in Table 1.

<Example 3>
(A) 20 parts by weight of bis (β-epithiopropyl) sulfide as the compound, (b) 9.5 parts by weight of m-tetramethylxylylene diisocyanate as the compound, and (c) bis (2-mercaptoethyl) sulfide 10 as the compound .5 parts by weight, (d) 0.005 part by weight of tetrabutylphosphonium bromide as a compound was mixed and prepolymerized at 15 ° C. for 20 hours, and (b) the consumption of isocyanate groups in the compound was 70%. This was confirmed by FT-IR. 60 parts by weight of bis (β-epithiopropyl) sulfide as a compound (a) is added to the preliminary reaction solution, and 0.1 part by weight of tetrabutylphosphonium bromide and 0.001 part by weight of dibutyltin dichloride are mixed as a compound (d). Thus, a uniform resin composition was obtained. Hereinafter, after the degassing treatment of the resin composition, the same procedure as in Example 1 was performed. The obtained cured product had not only excellent optical properties and physical properties, but also a good surface state and color tone, and good heat resistance, optical distortion and transparency. The results of cloudiness are shown in Table 1.

<Example 4>
(A) 40 parts by weight of bis (β-epithiopropyl) sulfide as the compound, 9.5 parts by weight of m-tetramethylxylylene diisocyanate as the compound (b), and bis (2-mercaptoethyl) sulfide 10 as the compound (c) 0.5 part by weight, (d) 0.005 part by weight of tetrabutylphosphonium bromide as a compound was mixed and prepolymerized at 40 ° C. for 24 hours, and (b) the consumption of isocyanate groups in the compound was 80%. This was confirmed by FT-IR. 40 parts by weight of bis (β-epithiopropyl) sulfide as a compound (a) is added to the prepolymerized solution, and 0.1 part by weight of tetrabutylphosphonium bromide is mixed as a compound (d) to obtain a uniform resin composition. did. Hereinafter, after the degassing treatment of the resin composition, the same procedure as in Example 1 was performed. The obtained cured product had not only excellent optical properties and physical properties, but also a good surface state and color tone, and good heat resistance, optical distortion and transparency. The results of cloudiness are shown in Table 1.

<Example 5>
(A) 20 parts by weight of bis (β-epithiopropyl) sulfide as the compound, 9.0 parts by weight of m-tetramethylxylylene diisocyanate as the compound (b), bis (2-mercaptoethyl) sulfide 13 as the compound (c) 0.0 part by weight, (d) 0.005 part by weight of tetrabutylphosphonium bromide as a compound, prepolymerized at 30 ° C. for 24 hours, and (b) the consumption of isocyanate groups in the compound is 90%. It confirmed with FT-IR. To this prepolymerized solution, 58 parts by weight of bis (β-epithiopropyl) sulfide as a compound (a) was added, and 0.1 part by weight of tetrabutylphosphonium bromide as a compound (d) was mixed to obtain a uniform resin composition. did. A homogeneous solution was obtained. Hereinafter, after the degassing treatment of the resin composition, the same procedure as in Example 1 was performed. The obtained cured product had not only excellent optical properties and physical properties, but also a good surface state and color tone, and good heat resistance, optical distortion and transparency. The results of cloudiness are shown in Table 1.

<Example 6>
(A) 20 parts by weight of bis (β-epithiopropyl) sulfide as the compound, (b) 10.5 parts by weight of m-tetramethylxylylene diisocyanate as the compound, (c) 2,5-bis (mercaptomethyl) as the compound -1,4-dithiane 16.5 parts by weight, (d) tetrabutylphosphonium bromide 0.005 parts by weight as a compound, prepolymerized at 30 ° C. for 8 hours, (b) consumption of isocyanate groups in the compound Was confirmed by FT-IR to be 80%. To this prepolymerized solution, 53 parts by weight of bis (β-epithiopropyl) sulfide as a compound (a) was added, and 0.1 part by weight of tetrabutylphosphonium bromide as a compound (d) was mixed to obtain a uniform resin composition. did. Hereinafter, after the degassing treatment of the resin composition, the same procedure as in Example 1 was performed. The obtained cured product had not only excellent optical properties and physical properties, but also a good surface state and color tone, and good heat resistance, optical distortion and transparency. The results of cloudiness are shown in Table 1.

<Comparative example 1>
(A) 80 parts by weight of bis (β-epithiopropyl) sulfide as the compound, 9.5 parts by weight of m-tetramethylxylylene diisocyanate as the compound (b), and bis (2-mercaptoethyl) sulfide 10 as the compound (c) 0.5 part by weight and 0.1 part by weight of tetrabutylphosphonium bromide as the compound (d) were mixed to obtain a uniform resin composition. The obtained resin composition was degassed and filtered through a 0.5 μm PTFE membrane filter. Next, this composition was poured into a mold in which the outer periphery of two opposing molds was wound with an adhesive tape (# 6263-50, manufactured by SLIONTEC), and 30 ° C to 100 ° C for 10 hours at 30 ° C using an oven. The temperature was raised to 10 hours over 10 hours and finally polymerized and cured at 100 ° C. for 1 hour. The cured product was allowed to cool to room temperature, released from the mold, and then annealed at 110 ° C. for 1 hour. Since the obtained cured product was not prepolymerized, white turbidity was observed. The results are shown in Table 2.

<Comparative example 2>
(A) 78 parts by weight of bis (β-epithiopropyl) sulfide as the compound, 9.0 parts by weight of m-tetramethylxylylene diisocyanate as the compound (b), bis (2-mercaptoethyl) sulfide 13 as the compound (c) Comparative Example 1 was carried out except that 0.0 part by weight and 0.1 part by weight of tetrabutylphosphonium bromide were used as the compound (d). Since the obtained cured product was not prepolymerized, white turbidity was observed. The results are shown in Table 2.

<Comparative Example 3>
(A) 73 parts by weight of bis (β-epithiopropyl) sulfide as the compound, (b) 10.5 parts by weight of m-tetramethylxylylene diisocyanate as the compound, (c) 2,5-bis (mercaptomethyl) as the compound The same procedure as in Comparative Example 1 was conducted except that 16.5 parts by weight of 1,4-dithiane and 0.1 parts by weight of tetrabutylphosphonium bromide were used as the compound (d). Since the obtained cured product was not prepolymerized, white turbidity was observed. The results are shown in Table 2.

a-1: Bis (β-epithiopropyl) sulfide
b-1: m-tetramethylxylylene diisocyanate
c-1: Bis (2-mercaptoethyl) sulfide
c-2: 2,5-bis (mercaptomethyl) -1,4-dithiane
d-1: Tetrabutylphosphonium bromide
d ': Dibutyltin dichloride

It is sectional drawing which shows the state which assembled the type | mold for shaping | molding.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Glass mold 2 ... Adhesive tape with which adhesive material was apply | coated 3 ... Space in which a resin composition enters

Claims (6)

(A) a compound represented by the following formula (1):

(B) a compound represented by the following formula (2);

A thiol group having 2 or more in one molecule (c) Ri Do from compounds, (a) total for compounds 50-90 parts by weight and (b) Compound (c) compound be 50 to 10 parts by weight , (b) when the ratio of the SH groups of the NCO groups of the compound (c) compound is polymerized SH group / NCO group = 1.0 to 2.5 der Ru composition for optical materials, pre-compound (b) And (c) at most 40 parts by weight of (a) compound with respect to a total amount of 10-15 parts by weight of compound, and (b) compound and (c) compound are 50% of the isocyanate groups of (b) compound. After preliminarily polymerizing to be consumed , the remaining compound (a) is added, and a pressure-sensitive adhesive tape coated with a pressure-sensitive adhesive is filled in a mold wound around the outer periphery of two opposing molds, and polymerization is performed. A method for producing an optical material. The method for producing an optical material according to claim 1, wherein the total amount of the compound (b) and the compound (c) is 50 to 10 parts by weight with respect to 60 to 85 parts by weight of the compound (a). The method for producing an optical material according to claim 1 or 2, wherein the compound (a) is bis (β-epithiopropyl) sulfide and / or bis (β-epithiopropyl) disulfide. The method for producing an optical material according to any one of claims 1 to 3, wherein the compound (b) is m-tetramethylxylylene diisocyanate. The method for producing an optical material according to any one of claims 1 to 4, wherein the compound (c) is bis (2-mercaptoethyl) sulfide and / or 2,5-bis (mercaptomethyl) -1,5-dithiane. . The method for producing an optical material according to any one of claims 1 to 5, wherein 0.0005 to 5 parts by weight of a polymerization catalyst is added to 100 parts by weight of the total of (a) to (c) compounds to obtain an optical material. .

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