JPH11124363A - New tri-or poly-functional selenium-containing polythiol - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound, preferably used for a transparent optical material or the like such as a plastic lens by allowing an aliphatic chain structure to include a selenium atom to have three or more functions. SOLUTION: This compound is a compound of the formula (X)m -(SH)n [X is an alkylene containing one or more Se's; (m) is 1-20; (n) is 3-6], preferably the compound of formula I [R1 to R<4> are each H, mercapto, CH2 SH, YCH2 CH2 SH (Y is S or Se) or the like] e.g. 2-mercaptoethylseleno-1 and 3-propanediol. A compound of the formula (X)m -(SH)n is produced, for example, by the method or the like by allowing a halohydrin of formula II (X is a halogen) to react with an alkali metal selenol to provide a hydroxyselenol body of formula III, allowing the hydroxyselenol body of formula III to react with an epihalohydrin to provide a polyol body, adding hydrogen halide acid, thiourea, etc., thereto to react with the polyol body, and hydrolyzing the product by a base to provide a compound of formula V.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel compound suitably used for a transparent optical material represented by a plastic lens and a composition containing the compound.

[0002]

2. Description of the Related Art Transparent optical materials and plastic lenses are molded products that require a high degree of transparency and optical homogeneity as apparent from their uses. As a material that has been widely used in these applications, a plastic material obtained by radically polymerizing diethylene glycol bis (allyl carbonate) (hereinafter abbreviated as DAC) is exemplified.

However, this DAC plastic material also has a problem that, when a plastic lens has a low refractive index (Nd) of 1.50, the edge becomes thick and lacks fashionability.

Various studies have been made to improve the refractive index in order to improve the above problems. For example, a method of reacting tetrabromobisphenol-A with an isocyanate compound (JP-A-58-164615), a method of polymerizing xylylenedithiol dimethacrylate (JP-A-64-31759), 2,5- Method using dimercaptomethyl-1,4-dithiane (JP-B-6-5)
323 publication) and the like.

[0005] The present inventors have also previously described a method using a polythiol having a sulfur atom other than a mercapto group in a molecule (Japanese Patent Application Laid-Open Nos. 2-270859 and 7-252207).
Publication).

[0006]

All of these methods are methods for improving the refractive index of a lens by introducing a halogen atom such as a benzene ring or bromine or a sulfur atom into the molecular structure of the compound. For example, when it is desired to further improve the refractive index, these methods alone are often insufficient. SUMMARY OF THE INVENTION An object of the present invention is to provide a material and a method that can sufficiently satisfy the strong demand for further increasing the refractive index of the lens and reducing the edge thickness of the lens.

[0007]

The present inventors have conducted intensive studies to meet the above-mentioned strong demands. As a result, the use of trifunctional or more functional polythiol having a selenium atom in the molecule further improves the refractive index. They found what they could do and arrived at the present invention.

That is, the present invention provides the following formula (1)

(X) _m- (SH) _n (1) (wherein, X represents an alkylene group containing at least one Se atom, m is an integer of 1 to 20, and n is an integer of 3 to 6) ) -Containing selenium-containing polythiol having three or more functional groups.
Furthermore, the trifunctional or higher selenium-containing polythiol described above is represented by the formula (2)

Embedded image A trifunctional or higher selenium-containing polythiol represented by the formula: In addition, a composition containing at least one or more trifunctional or higher selenium-containing polythiols described above. No trifunctional or higher polythiol having a selenium atom in the aliphatic chain structure has been known at all.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The selenium-containing polythiol according to the present invention represented by the above formula (1) has, as a central skeleton, a selenium-containing aliphatic chain structure in which one or more carbon atoms in the aliphatic chain structure are substituted with selenium atoms. It is a compound in which three or more mercapto groups are bonded to the selenium-containing aliphatic chain skeleton. The selenium-containing aliphatic chain structure is an aliphatic chain structure consisting of only a single bond, and may be a straight-chain alkylene or a branched alkylene. Further, some of the carbon atoms constituting the selenium-containing alkylene skeleton may be substituted with other atoms such as a sulfur atom or an oxygen atom other than the selenium atom.

[0010] The mercapto group may be bonded to separate atoms one by one or two or more to the same atom.

The selenium-containing polythiol represented by the formula (1) according to the present invention is, for example, a Thermistry.
of selenium and tellurium
compounds (1986, Saul Data)
edited by i and Zvi Roopport, John W.
iley & Sons Publishing) and Selenium
reagents and intermediate
s in organic synthesis (19
1986, edited by JE Baldwin, Pergamon
Press publication) and other selenium-containing aliphatic compounds using selenium compounds such as selenium halides, alkali metal selenides, alkali metal selenols, alkyl (di) selenides, alkyl selenols, and hydrogen selenide. A compound having a chain structure as a central skeleton was synthesized, and then described in the literature Synthetic organic ch.
mistry (1953, Romeo B. Wag)
ner and Harry D. Book edition, Joh
n Wiley & Sons) and the like by introducing a mercapto group by a known organic reaction or the like.

The selenium-containing polythiol represented by the formula (1) is disclosed in JP-A-2-270859 and JP-A-7-2702.
It can also be obtained by changing a part of the raw material of the synthesis method described in JP 52207A to a selenium compound. For example, 2-hydroxyethyl selenol is used instead of 2-mercaptoethanol, or sodium selenide is used instead of sodium sulfide.

A specific example will be shown below, and the manufacturing method will be described according to the manufacturing process.

Embedded image

The hydroxyselenol compound of the formula (4) is synthesized by reacting the halohydrin of the formula (3) with an alkali metal selenol such as sodium selenol and potassium selenol. The alkali metal selenols used here are described, for example, in the literature Handbook of prepar.
active inorganic chemistry
(Volume1, second edition, 19
63, Georg Brauer, Academic
Press Publishing). The amount of the alkali metal selenol to be used is preferably from 1 to 5 equivalents, particularly preferably from 1 to 3 equivalents, based on the halogen atoms of the raw material halohydrin. The reaction temperature is about -10
It is the range of -150 ° C, and 0-120 ° C is preferred. As the reaction solvent, it is more efficient to use the solvent used for the synthesis of the alkali metal selenol as it is. For example, water, methanol, ethanol, isopropanol, ethylene glycol and the like.

Next, an epihalohydrin such as epichlorohydrin or epibromohydrin is reacted with the hydroxyselenol compound of the formula (4) to obtain a polyol compound of the formula (5). Epihalohydrin is used in an amount of 0.4 to 0.4 with respect to the hydroseleno group of the hydroxyselenol compound of the formula (4).
The molar ratio is 0.6 times, particularly preferably 0.5 to 0.55 times. In this case, organic bases such as triethylamine, pyridine, sodium hydroxide and potassium hydroxide,
The use of an inorganic base or the like often gives better results. The amount of these bases used is in the range of 0.5 to 2 equivalents, preferably 0.5 to 1 equivalent, based on the hydroseleno group of the hydroxyselenol compound of the formula (4). The reaction temperature ranges from 0 to 100 ° C, preferably from 5 to 50 ° C.
Although a reaction solvent may or may not be used, it is more efficient to use a solvent at the time of synthesizing the alkali metal selenol, as described above.

The resulting polyol compound of the formula (5) is added with a hydrohalic acid such as hydrochloric acid or hydrobromic acid and thiourea, and if necessary, a known solvent such as water or alcohol, and heated and stirred. , To form a thiuronium salt. The amount of the hydrohalic acid to be used is 1 to 20 equivalents, preferably 1 to 5 equivalents, relative to the hydroxy group of the polyol of formula (5).
The amount of the thiourea to be used is 1 to 5 equivalents, preferably 1 to 3 equivalents, relative to the hydroxy group of the polyol of the formula (5).
The reaction temperature ranges from 0 to 150 ° C, preferably from 60 to 120 ° C. Next, hydrolysis is carried out with a base such as caustic soda or aqueous ammonia to obtain the desired polythiol compound of the formula (6). The amount of the base to be used is preferably 1 to 3 equivalents, more preferably 1.1 to 2 equivalents, based on the previously used hydrohalic acid. The reaction temperature ranges from 0 to 120C, preferably from 20 to 80C.

Other methods for obtaining a selenium-containing polythiol form include, for example, a method of synthesizing a corresponding selenium-containing halogen form and substituting a halogen atom or the like of the halogen form with a mercapto group, or a method of obtaining a corresponding disulfide form. There is a method of reducing to a mercapto group.

The selenium-containing halogen compounds are compounds having an electron-withdrawing group, such as the corresponding chloro form, bromide form, methanesulfonate form, benzenesulfonate form and toluenesulfonate form. As a method for synthesizing the selenium-containing halogens, for example, a corresponding hydroxy compound is reacted with hydrochloric acid, hydrobromic acid, thionyl chloride, phosphorus tribromide, methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, or the like. Method, method of reacting olefins such as ethylene and propylene with halogenated selenides such as dichlorodiselenide, dibromodiselenide, terachloroselenium, and tetrabromoselenium; compounds having an electrophilic functional group such as ketone, aldehyde, and acetal And a method of reacting a compound with a selenol halide.

As a method for obtaining a selenium-containing polythiol compound by substituting an electron-withdrawing group of a selenium-containing halogen compound with a mercapto group, for example, a method using thiourea, a method using sodium hydrosulfide, potassium polysulfide, sodium polysulfide, etc. Various known reactions such as a method using alkali metal polysulfides, a method using potassium xanthate, a method using Bunte salt, a method using alkali metal trithiocarbonates such as sodium trithiocarbonate and potassium trithiocarbonate are used. Can be.

Examples of the reduction method for reducing the corresponding disulfide to synthesize the polythiol of the formula (6) include a reduction method using a metal such as iron or zinc and hydrochloric acid, a method using lithium aluminum hydride or sodium boron hydride, and the like. Is often used.

Here, when it is desired to change the length of the alkylene chain which is the central skeleton of the polythiol of the formula (6), for example,
There are the following methods. A method using a halogenated propanol in place of the halogenated ethanol of the formula (3), a method of reacting the polythiol of the formula (6) with the halogenated ethanol of the formula (3) again, Sodium selenide instead of knol body
And a method using sodium selenol.

The reaction solvent used until the synthesis of the polythiol of the formula (6) and its composition may or may not be used. When a solvent is used, for example, any of the general solvents described in the Solvent Handbook (edited by Shozo Asahara et al., Published by Kodansha) as long as they do not affect the reaction, extraction, and product, etc. Although hexane, benzene, toluene, xylene, chlorobenzene, dichlorobenzene, chloroform, dichloroethane, methanol, ethanol, isopropanol,
Water, etc.

Examples of the trifunctional or higher functional polythiol of the present invention other than the formula (6) exemplified in the synthesis method include, for example,
2-mercaptoethylseleno-1,3-propanedithiol, bis (1,3-dimercapto-2-propyl) selenide, bis [1,3-bis (mercaptoethylthio)
-2-propyl] selenide, bis [1,3-bis (mercaptoethylseleno) -2-propyl] selenide, bis (mercaptomethyl) -3,9-dithia-6-selenaundecane-1,11-dithiol, bis (Mercaptomethyl) -3,9-diselena-6-thiaundecane-1,
11-dithiol, bis (mercaptomethyl) -3,
6,9-triselenaundecane-1,11-dithiol, 2,3-bis (mercaptoethylseleno) butane-
1,4-dithiol, 1,2,3,4-tetrakis (mercaptoethylseleno) butane, 5,5-bis (mercaptomethyl) -3,7-diselenananane-1,9-dithiol, tris (mercaptomethyl)- 3-Selena-6
-Thiaoctane-1,8-dithiol.

It is essential that the composition of the present invention contains at least trifunctional or higher selenium-containing polythiol represented by the formula (1). In addition to the trifunctional or higher functional polythiol represented by the formula (1) according to the present invention, oligomers and prepolymers such as dimers, trimers, and tetramers thereof;
In the formula, n is 2 or less, a mercapto compound, a polymerization inhibitor, a resin agent and a resin modifier, an additive, a solvent used for synthesis, a raw material, and other organic compounds such as by-product impurities and inorganics. Compounds may also be included to such an extent that they do not pose a problem.

The above resin agent is a compound that reacts with a mercapto group to form a resin, and the resin modifier is a compound for the purpose of improving the physical properties of a resin obtained by polymerization. Examples of the resin agent and the resin modifier include mercapto compounds other than the formula (1), iso (thio) cyanate compounds other than the formula (1), (meth) acrylate compounds other than the formula (1), Allyl (vinyl, isopropenyl) compounds other than formula (1), (thio) epoxy compounds other than formula (1), carboxylic acids and carboxylic anhydrides, mercaptocarboxylic acids, hydroxys, amino acids and mercaptoamines , Amines and the like, and can be added until the required resin properties are obtained within a range without any problem.

Specifically, for example, ethanedithiol,
Bis (2-mercaptoethyl) sulfide, 2,3-dimercapto-1-propanol, 1,2,3-trimercaptopropane, pentaerythritol tetrakis (2
-Mercaptothioglycolate), pentaerythritol tetrakis (3-mercaptopropionate), trimethylolpropane tris (2-mercaptothioglycolate), trimethylolpropane tris (3-mercaptopropionate), 2,5-bis (Mercaptomethyl) thiophene, 2,5-dimercapto-1,4-dithiane, 2,5-dimercaptomethyl-1,4-dithiane, 2,3-bis (2-mercaptoethylthio) -1-
Propanethiol, bis (mercaptomethyl) -3,
Mercapto compounds such as 6,9-trithia-1,11-undecanedithiol, cyclohexyl isocyanate, cyclohexyl isothiocyanate, xylylene diisocyanate, α, α ′, α ″, α ″ ′-tetramethylxylylenediene Isocyanate, 3-isopropenyl-α, α'-dimethylbenzyl isocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, 1,3-bis (isocyanate Iso (thio) cyanates such as methyl) cyclohexane and bis (isocyanatomethyl) norbornane, methyl methacrylate, ethylene glycol dimethacrylate, neopentyl glycol diacrylate,
Bis (methacryloylmethyl) norbornene, bis (acryloylethoxyethyl) bisphenol F, bis (methacryloylethoxyethyl) bisphenol F,
Bis (acryloylethoxyethyl) bisphenol A, bis (methacryloylethoxyethyl) bisphenol A, glycerin dimethacrylate, trimethylolpropane tris (acrylate), trimethylolpropane tris (methacrylate), pentaerythritol tris (acrylate), pentaerythritol tetrakis (acrylate) ), (Meth) acrylates such as 2,5-bis (methacryloylthiomethyl) -1,4-dithiane, acrylonitrile, butadiene, styrene, divinylbenzene, diisopropenylbenzene, and allyl (such as diethylene glycol bis (allyl carbonate)). Vinyl, isopropenyl) compounds, bis (3-epithiopropyl) sulfide, 1,2-bis (3-epithiopropylthio) eta , 1,2-bis (3-epithiopropylthioethyl thio) -3- (3-epithiopropylthio) propane, vinylcyclohexene diepoxide, bisphenol A diglycidyl ether, 3,4
(Thio) epoxy compounds such as epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, 1,2-hexahydrophthalic acid diglycidyl ester, phthalic acid, phthalic anhydride, hexahydrophthalic anhydride, methylhexahydro Carboxylic acids and carboxylic anhydrides such as phthalic anhydride, maleic anhydride, trimellitic anhydride, and pyromellitic anhydride, thioglycolic acid,
3-mercaptopropionic acid, thiolactic acid, thiomalic acid, mercaptocarboxylic acids such as thiosalicylic acid, thiodiglycolic acid, thiodipropionic acid, carboxylic acids such as dithiodipropionic acid, glycerin, polyethylene glycol, polypropylene glycol, butanediol, Lactic acid, hydroxy compounds such as polylactic acid, aspartic acid, alanine, β-alanine, glycine, taurine,
Amino acids such as cysteine, cysteamine, aminobenzoic acid and mercaptoamines, hexamethylenediamine, isophoronediamine, bis (4-aminocyclohexyl) methane, 1,3-bis (aminomethyl) cyclohexane, bis (aminomethyl) norbornane; Examples thereof include amines such as m-xylylenediamine and metaphenylenediamine, but the resinizing agent and the resin modifier are not limited to only these exemplified compounds.

The resin agent and the resin modifier are:
If there is no problem, it may be added in advance in the reaction system or in the removal step. Also, as represented by the compounding during the polymerization operation, etc., after taking out the tri- or more functional polythiol of the present invention and the composition containing the same as a product,
You may add it again. These resin agents and resin modifiers may be used alone or in combination of two or more.

The resin and plastic lens obtained by polymerizing the selenium-containing polythiol or the composition according to the present invention are usually composed of a polythiol having three or more functional groups represented by the formula (1) and the above-mentioned resin agent and resin modifier. After defoaming the composition composed of a filler and the like by a suitable method such as stirring under reduced pressure if necessary, a defoaming liquid is poured into a molding mold made of metal or glass and resin, and then heat and / or It is obtained by a cast polymerization method in which polymerization is performed with radiation such as light. Although it is not impossible to mold by the reaction injection molding method used for molding general epoxy resins and large urethane resins, the obtained molded products tend to have optical distortion. It is rarely used as a method for producing a plastic lens that requires strict optical uniformity.

When performing the casting polymerization, a curing catalyst is preferably used for the purpose of shortening the polymerization time and the like. The type of the curing catalyst can not be limited because it varies greatly depending on the type of the resin agent and the resin modifier to be polymerized, but if described daringly, amines, phosphines, Lewis acids,
Radical polymerization catalysts, cationic polymerization catalysts and the like can be mentioned.

Specific examples include ethylamine, 2-
Aminoethanol, 4,4′-diaminodiphenylmethane, dibutylamine, triethylamine, tributylamine, triethylenediamine, N, N-diethylaminoethanol, N, N-dimethylcyclohexylamine,
N-methylmorpholine, piperidine, pyridine, β-picoline, 2-methylimidazole, dicyandiamide,
Succinic hydrazide, diaminomaleonitrile, diallyl melanin, aniline phenylphosphonate, ethylenediamine phenylphosphate, boron tetrafluoride / monoethylamine salt, boron trifluoride / monoethylamine complex, phosphorus pentafluoride / isopropylamine Complexes, amines such as arsenic pentafluoride / laurylamine complex, antimony pentafluoride / benzylamine complex, trimethylphosphine, triethylphosphine, tripropylphosphine, tributylphosphine, tricyclohexylphosphine, tribenzylphosphine, triphenylphosphine, , 2
-Phosphines such as bis (dimethylphosphino) ethane and 1,2-bis (diphenylphosphino) ethane, dimethyltin dichloride, dimethyltin oxide, tetrachlorotin, monobutyltin trichloride, dibutyltin dichloride, tributyltin monochloride , Tetrabutyltin, dibutyltin oxide, dibutyltin dilaurate, dibutyltin octanoate, tin stearate, zinc chloride, zinc acetylacetone, aluminum fluoride, aluminum chloride, triphenylaluminum, tetraisopropoxy titanium, tetrabutoxy titanium, tetrachloro titanium, Lewis acids such as calcium acetate, diisopropyl peroxydicarbonate, di-sec-butylperoxydicarbonate, acetylacetone peroxide, cumene hydroperoxide, -Butyl hydroperoxide, isobutyl peroxide, t-butylcumyl peroxide, 1,1-di-t-butylperoxycyclohexane, 1,1,3,3-tetramethylbutylperoxy neodecanoate, t- Butyl peroxybenzoate, 2,2'-azobis (4-methoxy-2,4-
Dimethylvaleronitrile), 2,2'-azobis (2-
Cyclopropylpropionitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), t-butylperoxy-2-ethylhexanoate, n-butyl-
4,4′-bis (t-butylperoxy) valerate,
Radical polymerization catalysts such as t-butyl peroxybenzoate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroarsenate, diphenyliodonium hexafluoroantimony, triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluorophosphate And the like, but are not limited to only these exemplified compounds. These may be used alone or in combination of two or more.

When the curing catalyst is added, the amount added is usually
It is used in the range of 0.001 to 10% by weight, preferably 0.01 to 5% by weight, based on the total weight of the composition containing trifunctional or higher selenium-containing polythiol according to the present invention. If less than 0.01%, the effect is small and 10wt
% Is possible, but for example, there may be inconveniences such as a reduction in pot life and a decrease in transparency, optical properties, weather resistance, and the like.

In addition to the curing catalyst, various known additives such as an internal release agent, a light stabilizer, an ultraviolet absorber, an antioxidant, an oil-soluble dye, a filler, and the like may be used according to the purpose without any problem. May be added.

The polymerization conditions in the case of thermal polymerization are not particularly limited because the conditions vary greatly depending on the composition containing selenium-containing polythiol having three or more functional groups according to the present invention, the type of curing catalyst, the shape of the mold, and the like. -50
This is performed at a temperature of 200 ° C. for 1 to 100 hours. In some cases, if the temperature is gradually raised in the temperature range of 10 ° C. to 150 ° C. and the polymerization is carried out for 4 to 70 hours, favorable results may be obtained.

The polymerization conditions in the case of radiation polymerization are as follows. As the type of radiation, ultraviolet light or visible light is preferably used, and among them, ultraviolet light having a wavelength of 400 nm or less, which often does not require use of a sensitizer having high coloring properties such as camphorquinone, is preferably used. As in the case of thermal polymerization, the amount of ultraviolet light cannot be particularly limited because conditions are greatly different depending on the composition containing the trifunctional or higher selenium-containing polythiol according to the present invention, the type of curing catalyst, the shape of the mold, and the like. 1-1000mJ / se
In many cases, irradiation is performed at an intensity of c for 1 to 7200 sec.
In some cases, irradiation is performed several times for the purpose of heat removal, or irradiation is performed after cooling.

In these polymerizations, thermal polymerization and radiation polymerization may be combined without any problem. The polymerized molded product and the plastic lens may be subjected to an annealing treatment as needed.

The obtained molded article and plastic lens may have anti-reflection, high hardness, chemical resistance,
Physical or chemical treatments such as surface polishing, antistatic, hard coat treatment, anti-reflection coat treatment, dyeing treatment, light control treatment and the like can be applied to impart antifogging property or fashionability.

[0037]

The present invention will be described below in more detail with reference to examples and comparative examples. The compounds were synthesized under nitrogen unless otherwise specified, and the performance test of the obtained lenses was evaluated by the following methods. Refractive index, Abbe number: Measured at 20 ° C. using a Pulrich refractometer. Heat resistance; measured by TMA.

Example 1 (Synthesis of polyol-1) 24.7 parts of metal selenium (0.
313 mol), Rongalit (HOCH ₂ SO ₂ Na.
2H ₂ O) 90 parts (0.584 mol), 70 parts of sodium hydroxide (1.75 mol) was dissolved in water 400 ml, this 1-bromo-2,3-propanediol 95.5 parts (0. 616 mol) was slowly added dropwise at room temperature, followed by aging at 50 ° C. for 6 hours. After completion of the reaction, water was distilled off under reduced pressure, then 500 ml of isopropanol was added and mixed, and insolubles were separated by filtration. The obtained filtrate was desolvated, and bis (2,2) was removed.
69 parts of a residue containing 3-dihydroxy-1-propyl) selenide (crude yield 96%) were obtained.

(Synthesis of Halogen) 140 parts (0.517 mol) of phosphorus tribromide was added dropwise to the residue while maintaining the internal temperature at 50 ° C., and the mixture was aged at 80 ° C. for 10 hours. After cooling to room temperature, 100 ml of water was added to a mixed solution containing 300 ml of chloroform.
1 was slowly added and washed with water, and the washing with water was repeated several times. The lower organic layer was desolvated to give 141 parts (94% crude yield) of a residue containing bis (2,3-dibromo-1-propyl) selenide.

(Synthesis of polythiol-1) 190 parts (2.50 mol) of thiourea and 10 parts of absolute ethanol
Under reflux with heating (78 to 7).
(9 ° C.) for 20 hours. After cooling, the generated insolubles were separated by filtration. To a mixture of the filter cake and 300 ml of toluene, 170 parts (2.50 mol) of 25% aqueous water was gradually added, and the mixture was hydrolyzed at an internal temperature of 50 to 60 ° C. for 3 hours.
After standing, the lower tank was discarded. The obtained organic layer was washed sequentially with 36% hydrochloric acid and pure water at room temperature, and then the solvent was distilled off.
The remaining residue is purified by silica gel column chromatography, and the purity is 95% (by HPLC).
Was obtained (purification yield: 41%). The results of the identification analysis are shown below.

[0041]

Embedded image (Elemental analysis value%) CHSSe theoretical value: 24.6 4.8 43.7 26.9 actual value: 24.5 4.9 43.4 26.8 (MS); m / z = 294 ( M ⁺ ) (IR); SH = 2540-2550 cm ^-1

Example 2 (Synthesis of Polyol-2) 60 parts of metal selenium (0.7 parts)
6 mol) was suspended in 1000 ml of anhydrous methanol, and 35 parts (0.925 mol) of sodium borohydride was added thereto.
Was dissolved in 500 ml of anhydrous methanol and slowly dropped while cooling in a water bath, followed by aging for 1 hour. To a concentrated solution obtained by removing the solvent from the reaction solution to about 500 ml, 95 parts (0.76 mol) of bromoethanol was added at an internal temperature of 20 to 30 ° C.
And aged at room temperature for 20 hours. 49%
31.0 parts (0.38 mol) of caustic soda were added dropwise to the reaction solution while maintaining the internal temperature at 20 to 30 ° C., and the mixture was aged at room temperature for 1 hour. Then, 35.2 parts (0.3%) of epichlorohydrin was added.
8 mol) at an internal temperature of 30 to 40 ° C. and aged at the same temperature for 2 hours. Finally, the solvent was removed to obtain a residue containing 1,3-bis (hydroxyethylseleno) -2-propanol.

(Synthesis of polythiol-2) To 100 parts (1.31 mol) of thiourea and 36% hydrochloric acid
Then, 00 parts (1.98 mol) were added and the mixture was heated under reflux (108 to
(110 ° C.) for 2 hours. After cooling to room temperature, 400 ml of toluene and 160 parts (2.35 mol) of 25% aqueous solution were added, hydrolysis was performed at 60 ° C. for 2 hours, and after standing still, the lower water tank was discarded. 36% of the obtained organic layer at room temperature
After sequentially washing with hydrochloric acid and pure water, the solvent was distilled off, and the remaining residue was purified by silica gel column chromatography to give 2,3-bis (2) -bis (96) having a purity of 96% (by HPLC) of the following formula (8). 90 parts of mercaptoethylseleno) -1-propanethiol were obtained (pure conversion yield: 64%). The results of the identification analysis are shown below.

[0044]

Embedded image (Elemental analysis value%) CHSSe Theoretical value: 23.7 4.6 27.1 44.6 Actual value: 23.5 4.5 27.2 44.4 (MS); m / z = 356 (MS); M ⁺ ) (IR); SH = 2540-2550 cm ^-1

Example 3 (Production of plastic lens)
30 parts of 3-bis (mercaptoethylseleno) -1-propanethiol, 24 parts of m-xylylene diisocyanate (hereinafter abbreviated as XDI), dibutyltin dichloride 0.1 part.
While demixing 008 parts (150 ppm) and 0.06 parts (1100 ppm) of dioctyl phosphoric acid, degassing was performed under reduced pressure. One hour later, the mixture is poured into a concave lens mold having a center thickness of 1.5 mm and composed of a glass mold and a resin gasket.
The temperature was gradually raised until the temperature reached 20 hours, and the resin was cooled and the internal plastic lens was taken out. Further, this plastic lens was reheated at 120 ° C. for 2 hours. Table 1 shows the results.

Comparative Example 1 The same test as in Example 3 was carried out except that 2,3-bis (mercaptoethylthio) -1-propanethiol was used instead of 2,3-bis (mercaptoethylseleno) -1-propanethiol. Was done. Table 1 shows the results.

[0047]

[Table 1]

[0048]

As described above, the refractive indexes of the transparent optical material and the plastic lens can be further improved.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // G02B 1/04 G02B 1/04 (72) Inventor Mamoru Tanaka 30 Asamuta-cho, Omuta-shi, Fukuoka Mitsui Chemicals, Inc. 72) Inventor Yoshinobu Kanamura 30 Asamuta-cho, Omuta-shi, Fukuoka Prefecture Inside Mitsui Chemicals, Inc. (72) Inventor Masahiko Kusumoto 3-5-2 Kasumigaseki, Chiyoda-ku, Tokyo Mitsui Chemicals, Inc.

Claims (3)

[Claims] (1) Formula (1) (X) _m- (SH) _n
(1) (wherein, X represents an alkylene group containing at least one Se atom, m is an integer of 1 to 20, and n is an integer of 3 to 6). . 2. The tri- or more functional selenium-containing polythiol according to claim 1, wherein the selenium-containing polythiol has the formula (2). A trifunctional or higher selenium-containing polythiol represented by the formula: 3. A composition comprising at least one selenium-containing polythiol having three or more functional groups according to claim 1.