JP2615182B2 - Method for producing high refractive index optical element and plastic lens, optical element obtained by the method, and plastic lens - Google Patents

Description

The present invention relates to a method for producing a high refractive index optical element and a high refractive index plastic lens, and an optical element obtained thereby.
Regarding plastic lenses, especially sulfur-containing aliphatic polyisocyanates except adduct modified products with polythiols, polyols containing no sulfur atoms, polythiols containing no hydroxy groups, and polythiols containing no sulfur atoms other than mercapto groups and hydroxy groups And a cast polymerization by adding an internal mold release agent to a mixture with an active hydrogen compound selected from the group consisting of polythiols containing at least one sulfur atom in addition to the mercapto group. The present invention relates to a method for producing a high refractive index plastic lens and a plastic lens obtained by the method.

BACKGROUND ART Plastic lenses are lightweight, hard to break, and can be dyed compared to inorganic lenses, and have recently been rapidly used in optical elements such as spectacle lenses, camera lenses, prisms, and optical waveguides.

[Conventional technology]

As a material for these lenses, there is a material obtained by radical polymerization of diethylene glycol bis (allyl carbonate) (hereinafter referred to as DAC). These resins have various characteristics such as being excellent in impact resistance, being lightweight, being excellent in dyeing properties, being excellent in workability such as cutting property, and polishing property. ing.

However, the lens obtained from the DAC has a smaller refractive index of n _D = 1.50 than the inorganic lens (n _D = 1.52), and in order to obtain optical characteristics equivalent to a glass lens, the center thickness, edge thickness, and It is necessary to increase the curvature, and it is inevitable that the overall thickness will increase. Therefore, a lens resin having a higher refractive index is desired.

Further, as one of the lens resins giving a high refractive index, a reaction between an isocyanate compound and a hydroxy compound such as diethylene glycol (Japanese Patent Laid-Open No. 57-136601) or a hydroxy compound containing a halogen atom such as tetrabromobisphenol A is used. Reaction (JP-A-58-16)
4615) and a plastic lens made of a polyurethane-based resin obtained by a reaction with a hydroxy compound having a diphenyl sulfide skeleton (Japanese Patent Application Laid-Open No. 60-194401).

In addition, the present inventors have proposed a reaction between an isocyanate compound and a hydroxy compound containing a sulfur atom as a resin for a high refractive index plastic lens (JP-A-60-217229), and further, a reaction with a polythiol compound (JP-A-60-160229). −199016,
JP-A-62-267316) has previously proposed a plastic lens made of a polyurethane resin or the like.

However, lenses made of these known resins are DA
Although the refractive index is improved compared to the lens using C, the dispersion is still insufficient, or because a compound having a large number of halogen atoms or aromatic rings in the molecule is used to improve the refractive index, the dispersion is low. It is disadvantageous in that it is large, has poor weather resistance, and has a large specific gravity.

Furthermore, in the production of these plastic lenses,
As an example of the use of an internal release agent to improve mold release during the molding of these materials, a method is known in which butyl phosphate is added to DAC. No internal mold release agent is actively used to impair the appearance of the product (Seiichi Mima, Polymer Digest, 3,39
(1984)).

On the other hand, when molding a polyurethane plastic lens such as a polyurethane or S-alkyl thiocarbamate lens, it is difficult to release the lens from the mold after polymerization. Therefore, the present inventors have proposed a method using an external release agent (Japanese Patent Laid-Open No. 62-267316) or a method using a polyolefin resin mold (Japanese Patent Application Laid-Open
62-236818).

[Problems to be solved by the invention]

However, the above-mentioned method is still insufficient as a method of improving mold release when casting and polymerizing these polyurethane plastic lenses.

That is, in the method using an external mold release agent, there is a problem that the surface treatment substance on the inner surface of the mold partially migrates to the surface or inside of the polymerized lens, causing unevenness on the lens surface or clouding of the lens. Further, each time a mold is used repeatedly, a mold release treatment is required each time, and as an industrial manufacturing method, it is complicated and the productivity of the lens is reduced, which is extremely uneconomical.

On the other hand, in the method using a polyolefin resin mold, since the resin mold is deformed by the temperature, the surface accuracy of the molded lens surface is poor, and it has been found that it is difficult to use in a field requiring a high surface accuracy. .

[Means for solving the problem]

The present inventors have generally added an internal mold release agent to a mixture of a sulfur-containing aliphatic polyisocyanate excluding an adduct modified product with a polythiol and an active hydrogen compound having two or more functional groups in advance, so that in general, Using a glass mold to be used, it was found that a plastic lens having high surface accuracy and excellent weather resistance can be produced industrially extremely efficiently without performing a special mold release treatment on the mold surface. Thus, the present invention has been completed.

That is, the present invention relates to one or two or more kinds of sulfur-containing aliphatic polyisocyanates excluding adduct modified products with polythiol, a polyol containing no sulfur atom, no hydroxyl group, and a sulfur atom other than the mercapto group. A mixture of a polythiol containing no and an active hydrogen compound selected from the group consisting of a polythiol having at least one sulfur atom in addition to a mercapto group without a mercapto group, and adding an internal mold release agent to the mixture. The present invention relates to a method for producing a high refractive index plastic lens characterized by being polymerized, and a plastic lens obtained by the method.

The greatest feature of the present invention lies in the year in which an internal mold release agent, which was conventionally considered not to be used in view of the physical properties of the lens, is actively used in the production of polyurethane plastic lenses. Moreover, surprisingly, it has been found for the first time that a lens having a high degree of transparency, optical homogeneity, and surface accuracy required for a lens can be industrially manufactured using an internal release agent. . In this regard, the present invention must be said to be an extremely pioneering invention in the field of the method of producing a polyurethane plastic lens.

Examples of the sulfur-containing aliphatic polyisocyanate excluding an adduct modified product with polythiol used as a raw material in the present invention include, for example, thiodiethyl diisocyanate, thiodipropyl diisocyanate, thiodihexyl diisocyanate, dimethyl sulfone diisocyanate, dithiodimethyl diisocyanate, dithiodiethyl diisocyanate, Acyclic sulfur-containing aliphatic isocyanates such as dithiodipropyl diisocyanate, aliphatic sulfur-containing isocyanates containing an aromatic ring such as bis [(4-isocyanatomethyl) phenyl] sulfide, 1,4-dithiane-2,5-diisocyanate, Examples include cyclic sulfur-containing aliphatic isocyanates such as 1,4-dithiane-2,5-diisocyanatemethyl, and aliphatic sulfur-containing isocyanates containing a heterocycle.

Further, these chlorine-substituted products, halogen-substituted compounds such as bromine-substituted products, furthermore, these buretation reaction products, adduct reaction products with trimethylolpropane,
Dimerization or trimerization reaction products can also be used.

These may be used alone or as a mixture of two or more.

As the active hydrogen compound used as a raw material, a polyol containing no sulfur atom, having no hydroxy group, and a polythiol containing no sulfur atom other than the mercapto group, having no hydroxy group, and at least other than the mercapto group Polythiols containing one sulfur atom are mentioned.

As a polyol containing no sulfur atom, for example,
Ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, glycerin, trimethylolethane, trimethylolpropane, butanetriol, 1,2-methylglucoside, pentaerythritol, dipentaerythritol, tripentaerythritol , Sorbitol, erythritol, threitol,
Ribitol, arabinitol, xylitol, allitol, mannitol, dorsitol, iditol, glycol, inositol, hexanetriol, triglycerose, digiplerol, triethylene glycol, polyethylene glycol, tris (2-hydroxyethyl) isocyanurate, cyclobutanediol, cyclopentanediol , cyclohexanediol, cycloheptane diol, cyclooctane diol, cyclohexane dimethanol, hydroxypropyl cyclohexanol, tricyclo [5,2,1,0 ^2,6] decane - dimethanol, bicyclo [4,3,0] - nonane diol , Dicyclohexanediol, tricyclo [5,3,1,1] dodecanediol, bicyclo [4,3,0] nonanedimethanol, tricyclo [5,3,1,1] dodecane-diethanol , Hydroxypropyltricyclo [5,3,1,1] dodecanol, spiro [3,4] octanediol, butylcyclohexanediol, 1,1'-bicyclohexylidenediol, cyclohexanetriol, maltitol, lactitol, dihydroxy Naphthalene, trihydroxynaphthalene, tetrahydroxynaphthalene, dihydroxybenzene, benzenetriol, biphenyltetraol, pyrogallol, (hydroxynaphthyl) pyrogallol, trihydroxyphenanthrene, bisphenol A, bisphenol E, xylylene glycol, di (2-hydroxyethoxy) benzene , Bisphenol A-bis- (2-hydroxyethyl ether), tetrabromobisphenol A, tetrabromobisphenol A-bis- (2-hydroxyethyl Chirueteru), dibromo neopentyl glycol, in addition to oxalic acid polyols such as epoxy resin,
Glutamic acid, adipic acid, acetic acid, propionic acid, cyclohexanecarboxylic acid, β-oxocyclohexanepropionic acid, dimer acid, phthalic acid, isophthalic acid, salicylic acid, 3-bromopropionic acid, 2-bromoglycolic acid, dicarboxycyclohexane, pyromellitic acid,
Butanetetracarboxylic acid, condensation reaction product of an organic polybasic acid such as bromophthalic acid with the polyol, addition reaction product of the polyol with an alkylene oxide such as ethylene oxide or propylene oxide, alkylene polyamine and ethylene oxide, or propylene oxide And addition reaction products with alkylene oxides.

Further, a halogen-substituted product such as a chlorine-substituted product or a bromine-substituted product may be used.

Examples of the polythiol having no hydroxy group and containing no sulfur atom other than the mercapto group include, for example, methanedithiol, 1,2-ethanedithiol, 1,1-propanedithiol, 1,2-propanedithiol, 3-propanedithiol, 2,2-propanedithiol, 1,6-hexanedithiol, 1,2,3-propanetrithiol, 1,1-cyclohexanedithiol, 1,2-cyclohexanedithiol, 2,2-dimethylpropane- 1,3-dithiol, 3,4
-Dimethoxybutane-1,2-dithiol, 2-methylcyclohexane-2,3-dithiol, bicyclo [2,2,1] pepta-exo-cis-2,3-dithiol, 1,1-bis (mercaptomethyl) Cyclohexane, bis-thiomalate (2-
Mercaptoethyl ester), 2,3-dimercaptosuccinic acid (2-mercaptoethylester), 2,3-dimercapto-1-propanol (2-mercaptoacetate), 2,3-dimercapto-1-propanol (3-mercapto Propionate), diethylene glycol bis (2-mercaptoacetate), diethylene glycol bis (3-mercaptopropionate), 1,2-dimercaptopropyl methyl ether, 2,3-dimercaptopropyl methyl ether, 2,2-bis (Mercaptomethyl) -1,3-propanedithiol, bis (2-mercaptoethyl) ether, ethylene glycol bis (2-mercaptoacetate), ethylene glycol bis (3-
Mercaptopropionate), trimethylolpropane tris (2-mercaptoacetate), trimethylolpropanetris (3-mercaptopropionate), pentaerythritol tetrakis (2-mercaptoacetate), pentaerythritol tetrakis (3-mercaptopropionate) ), And their halogen-substituted compounds such as chlorine-substituted and bromine-substituted compounds;
1,2-dimercaptobenzene, 1,3-dimercaptobenzene, 1,4-dimercaptobenzene, 1,2-bis (mercaptomethyl) benzene, 1,3-bis (mercaptomethyl)
Benzene, 1,4-bis (mercaptomethyl) benzene,
1,2-bis (mercaptoethyl) benzene, 1,3-bis (mercaptoethyl) benzene, 1,4-bis (mercaptoethyl) benzene, 1,2-bis (mercaptomethyleneoxy) benzene, 1,3-bis (Mercaptomethyleneoxy) benzene, 1,4-bis (mercaptomethyleneoxy) benzene, 1,2-bis (mercaptoethyleneoxy) benzene, 1,3-bis (mercaptoethyleneoxy) benzene, 1,4-bis (mercapto) Ethyleneoxy) benzene, 1,2,3-trimercaptobenzene, 1,2,4
-Trimercaptobenzene, 1,3,5-trimercaptobenzene, 1,2,3-tris (mercaptomethyl) benzene, 1,2,4-tris (mercaptomethyl) benzene, 1,
3,5-tris (mercaptomethyl) benzene, 1,2,3-tris (mercaptoethyl) benzene, 1,2,4-tris (mercaptoethyl) benzene, 1,3,5-tris (mercaptoethyl) benzene, 1,2,3-tris (mercaptomethyleneoxy) benzene, 1,2,4-tris (mercaptomethyleneoxy) benzene, 1,3,5-tris (mercaptomethyleneoxy) benzene, 1,2,3-tris ( Mercaptoethyleneoxy) benzene, 1,2,4-tris (mercaptoethyleneoxy) benzene, 1,3,5-tris (mercaptoethyleneoxy) benzene, 1,2,3,4-tetramercaptobenzene, 1,2, 3,5-tetramercaptobenzene, 1,2,4,5-tetramercaptobenzene, 1,2,
3,4-tetrakis (mercaptomethyl) benzene, 1,2,
3,5-tetrakis (mercaptomethyl) benzene, 1,2,
4,5-tetrakis (mercaptomethyl) benzene, 1,2,
3,4-tetrakis (mercaptoethyl) benzene, 1,2,
3,5-tetrakis (mercaptoethyl) benzene, 1,2,
4,5-tetrakis (mercaptoethyl) benzene, 1,2,
3,4-tetrakis (mercaptomethyleneoxy) benzene, 1,2,4,5-tetrakis (mercaptomethyleneoxy) benzene, 1,2,3,4-tetrakis (mercaptoethyleneoxy) benzene, 1,2,3, 5-tetrakis (mercaptoethyleneoxy) benzene, 1,2,4,5-tetrakis (mercaptoethyleneoxy) benzene, 2,2'-dimercaptobiphenyl, 4,4'-dimercaptobiphenyl, 4,4'-di Mercaptobibenzyl, 2,5-toluenedithiol, 3,4-toluenedithiol, 1,4-naphthalenedithiol, 1,5-naphthalenedithiol, 2,6-naphthalenedithiol, 2,7-naphthalenedithiol, 2,4- Dimethylbenzene-1,3-dithiol, 4,5-dimethylbenzene-1,3-dithiol, 9,10-anthracenedimethanethiol, 1,3-di (p-methoxyphenyl) propane-2,2 Dithiol, 1,3-diphenyl-2,2-propane
Dithiol, phenylmethane-1,1-dithiol, 2,4-
Aromatic polythiols such as di (p-mercaptophenyl) pentane, and 2,5-dichlorobenzene-1,3-dithiol, 1,3-di (p-chlorophenyl) propane-2,2-
Halogen-substituted aroma such as chlorine-substitution or bromine-substitution such as dithiol, 3,4,5-tribromo-1,2-dimercaptobenzene, and 2,3,4,6-tetrachloro-1,5-bis (mercaptomethyl) benzene Group polythiols, also 2-methylamino-
4,6-dithiol-sym-triazine, 2-ethylamino-4,6-dithiol-sym-triazine, 2-amino-4,
6-dithiol-sym-triazine, 2-morpholino-4,
6-dithiol-sym-triazine, 2-cyclohexylamino-4,6-dithiol-sym-triazine, 2-methoxy-4,6-dithiol-sym-triazine, 2-phenoxy-4,6-dithiol-sym-triazine , 2-thiobenzeneoxy-4,6-dithiol-sym-triazine, 2
And polythiols containing a heterocyclic ring such as -thiobutyloxy-4,6-dithiol-sym-triazine, and halogen-substituted compounds such as chlorine-substituted and bromine-substituted products thereof.

Examples of the polythiol having no hydroxy group and containing at least one sulfur atom in addition to the mercapto group include 1,2-bis (mercaptomethylthio) benzene, 1,3-bis (mercaptomethylthio) benzene,
1,4-bis (mercaptomethylthio) benzene, 1,2-bis (mercaptoethylthio) benzene, 1,3-bis (mercaptoethylthio) benzene, 1,4-bis (mercaptoethylthio) benzene, 1,2 1,3-tris (mercaptomethylthio) benzene, 1,2,4-tris (mercaptomethylthio) benzene, 1,3,5-tris (mercaptomethylthio) benzene, 1,2,3-tris (mercaptoethylthio) benzene, 1,2,4-tris (mercaptoethylthio) benzene, 1,3,5-tris (mercaptoethylthio) benzene, 1,2,3,4-tetrakis (mercaptomethylthio) benzene, 1,2,3,5 -Tetrakis (mercaptomethylthio) benzene, 1,2,4,5-tetrakis (mercaptomethylthio) benzene, 1,2,3,4-tetrakis (mercaptoethylthio) benzene, 1,2,3,5-tetrakis (mer Putoechiruchio) benzene, 1,2,4,5-tetrakis (mercaptoethylthio) benzene, and aromatic, such as these nuclear alkylated polythiol, bis (mercaptomethyl) sulfide, bis (mercaptoethyl)
Sulfide, bis (mercaptopropyl) sulfide,
Bis (mercaptoethylthio) methane, bis (2-mercaptoethylthio) methane, bis (3-mercaptopropylthio) methane, 1,2-bis (mercaptomethylthio) ethane, 1,2-bis (mercaptoethylthio) ethane , 1,2-bis (mercaptopropylthio) ethane, 1,3
-Bis (mercaptomethylthio) propane, 1,3-bis (2-mercaptoethylthio) propane, 1,3-bis (3-mercaptopropylthio) propane, 1,2,3-tris (mercaptomethylthio) propane, 1 , 2,3-Tris (2-mercaptoethylthio) propane, 1,2,3-tris (3-mercaptoethylthio) propane, tetrakis (mercaptomethylthio) methane, tetrakis (2-
Mercaptoethylthiomethyl) methane, tetrakis (3
-Mercaptopropylthiomethyl) methane, bis (2,3
-Dimercaptopropyl) sulfide, 2,5-dimercapto-1,4-dithiane, 2,5-dimercaptomethyl-1,4
Dithiane, 2,6-dimercaptomethyl-1,4-dithiane, bis (mercaptomethyl) disulfide, bis (mercaptoethyl) disulfide, bis (mercaptopropyl) disulfide and the like, and esters of thioglycolic acid and mercaptopropionic acid , Hydroxymethyl sulfide bis (2-mercaptoacetate), hydroxymethyl sulfide bis (3-mercaptopropionate), hydroxyethyl sulfide bis (2-mercaptoacetate), hydroxyethyl sulfide bis (3-mercaptopropionate), hydroxy Propyl sulfide bis (2-mercapto acetate), hydroxypropyl sulfide bis (3-mercapto propionate), hydroxymethyl disulfide bis (2
-Mercaptoacetate), hydroxymethyldisulfidebis (3-mercaptopropionate), hydroxyethyldisulfidebis (2-mercaptoacetate), hydroxyethyldisulfidebis (3-mercaptopropionate), hydroxypropyldisulfidebis (2- Mercaptoacetate), hydroxypropyldisulfidebis (3-mercaptopropionate), 2-mercaptoethyletherbis (2-mercaptoacetate), 2-mercaptoethyletherbis (3-mercaptopropionate), 1,4-dithiane −
2,5-diol bis (2-mercaptoacetate), 1,4
Dithiane-2,5-diol bis (3-mercaptopropionate), thioglycolic acid bis (2-mercaptoethyl ester), thiodipropionic acid bis (2-mercaptoethyl ester), bis-4-thiodibutylate ( 2-mercaptoethyl ester), bis (2-mercaptoethyl ester) dithiodiglycolate, bis (2-mercaptoethyl ester) dithiodipropionate,
Bis (2-mercaptoethyl ester) 4,4-dithiodibutylate, Bis (2,3-dimercaptopropyl ester) thioglycolate, Bis (2,3
Aliphatic polythiols such as bis (2,3-dimercaptopropyl ester), dithiodiglycolic acid bis (2,3-dimercaptopropyl ester) and 3,4-thiophenedithiol , Bismuthiol, 2,5-dimercapto-1,
And heterocyclic compounds such as 3,4-thiadiazole. Further, a halogen-substituted product such as a chlorine-substituted product or a bromine-substituted product may be used.

These active hydrogen compounds may be used alone or as a mixture of two or more.

The usage ratio of these polyisocyanates and active hydrogen compounds is such that NCO / (SH + OH) (functional group molar ratio) is usually 0.1.
It is in the range of 5 to 3.0, preferably in the range of 0.5 to 1.5.

The polyurethane-based plastic lens of the present invention is made of a urethane resin or an S-alkyl thiocarbamate resin, and is formed of a urethane bond formed by an isocyanate group and a hydroxy group, or an S-alkyl thiocarbamate formed by an isocyanate group and a mercapto group. Although it is mainly composed of an ester bond, depending on the purpose, other than the above two types of bonds, it is of course possible to contain an allohanate bond, a urea bond, a biuret bond, or the like.

For example, urethane bond or thiocarbamic acid S
It is often desirable to increase the crosslink density by further reacting the alkyl ester bond with an isocyanate group. In this case, the reaction temperature should be at least
Increase the temperature to 100 ° C or higher and use a lot of isocyanate components. Alternatively, an urine bond or a biuret bond can be used by partially using an amine or the like.

When a compound other than the hydroxy compound or the mercapto compound that reacts with the isocyanate compound is used, it is necessary to pay attention to coloring at times.

Also, as in known molding methods depending on the purpose,
Various substances such as a chain extender, a crosslinking agent, a light stabilizer, an ultraviolet absorber, an antioxidant, an oil-soluble dye, and a filler may be added.

In order to adjust the reaction rate to a desired one, a known reaction catalyst used in the production of polyurethane and S-alkyl thiocarbamate can be appropriately added.

The plastic lens of the present invention is usually obtained by cast polymerization. Specifically, a sulfur-containing aliphatic polyisocyanate excluding an adduct modified product with polythiol, an active hydrogen compound, and an internal release agent are mixed, injected into a mold, and polymerized.

The internal release agent used in the present invention is, for example, a fluorine-based nonionic surfactant, a silicon-based nonionic surfactant, an alkyl quaternary ammonium salt, an acidic phosphate, a liquid paraffin, a wax, a higher fatty acid and a metal salt thereof. And higher fatty acid esters, higher fatty alcohols, bisamides, polysiloxanes, fatty acid amine ethylene oxide adducts, and the like. These are appropriately selected from the combination of monomers, polymerization conditions, economy, and ease of handling.

These internal release agents may be used alone or in combination of two or more.

The fluorine-based nonionic surfactant and the silicon-based nonionic surfactant used as the internal release agent in the present invention have a perfluoroalkyl group or a dimethylpolysiloxane group in the molecule, and have a hydroxyalkyl group or a phosphate group. And the former fluorine-based nonionic surfactants are Unidyne DS-401 (manufactured by Daikin Industries, Ltd.), Unidyne DS-403 (manufactured by Daikin Industries, Ltd.), F-Top EF122A (manufactured by Shin-Akita Chemical Co., Ltd.) , F-top EF126 (manufactured by Shin-Akita Kasei Co., Ltd.) and F-top EF301 (manufactured by Shin-Akita Kasei Co., Ltd.). As the latter nonionic surfactant, there is Dow Chemical's prototype, Q2-120A. .

The alkyl quaternary ammonium salt used as the internal mold release agent in the present invention is generally known as a cationic surfactant, and examples thereof include alkyl quaternary ammonium halides, phosphates, sulfates and the like. Yes, trimethylcetyl ammonium chloride, trimethyl stearyl ammonium chloride, dimethyl ethyl cetyl ammonium chloride,
Triethyl dodecyl ammonium chloride, trioctyl methyl ammonium chloride, diethyl cyclohexyl decyl ammonium chloride and the like can be mentioned.

Further, as the acidic phosphate used as the internal mold release agent in the present invention, isopropyl acid phosphate,
Diisopropyl acid phosphate, butyl acid phosphate, dibutyl acid phosphate, octyl acid phosphate, dioctyl acid phosphate, isodecyl acid phosphate, diisodecyl acid phosphate, tridecyl acid phosphate, bis (tridecyl acid) phosphate, JP-506 (Johoku Chemical Co., Ltd.) and the like.

Metal salts of higher fatty acids used as an internal mold release agent in the present invention include zinc salts such as stearic acid, oleic acid, octanoic acid, lauric acid, behenic acid, and ricinoleic acid, calcium salts, magnesium salts, nickel salts, and copper salts. Etc., specifically, zinc stearate, zinc oleate, zinc palmitate, zinc laurate, calcium stearate, calcium oleate, calcium palmitate, calcium laurate, magnesium stearate, magnesium oleate, magnesium laurate, Examples include magnesium palmitate, nickel stearate, nickel oleate, nickel palmitate, nickel laurate, copper stearate, copper oleate, copper laurate, copper palmitate, and the like.

The higher fatty acid ester used as the internal mold release agent in the present invention includes, for example, higher fatty acids such as stearic acid, oleic acid, octanoic acid, lauric acid, ricinoleic acid and ethylene glycol, dihydroxypropane, dihydroxybutane, neopentyl glycol, dihydroxy An ester with an alcohol such as hexane.

The amount of the internal release agent to be used is usually 0.1 or more as a mixture of two or more kinds with respect to the total weight of the monomer mixture.
It is in the range of 1010,000 ppm, preferably in the range of 1１〜5,000 ppm.

The lower limit of the range of the addition amount is determined as the minimum amount for the release ability to be exhibited, but the upper limit is that if the addition amount is extremely large, the release from the glass or metal mold during polymerization may occur. , The lens easily becomes cloudy, which is not preferable, but the type of the internal release agent, the type of the monomer, the combination,
Since these phenomena are greatly affected by the polymerization conditions, 10,000 ppm is not limited.

The polymerization temperature and time vary depending on the type of monomer, additives such as a release agent, etc., but are usually -20 ° C to 200 ° C, preferably room temperature to 150 ° C, and preferably 50 to 120 ° C for 0.5 to 72 hours. .

The polymerized lens may be annealed as needed.

The plastic lens of the present invention thus obtained has high surface accuracy and excellent optical properties, is lightweight and has excellent impact resistance, and is used as an optical element material for eyeglass lenses, camera lenses, prisms, optical waveguides, and the like. It is suitable to do.

In addition, the plastic lens of the present invention has surface polishing, antistatic, anti-reflection, high hardness, high abrasion resistance, high chemical resistance, high anti-fogging property, or high fashion properties, if necessary. Physical or chemical treatment such as treatment, hard coat treatment, anti-reflection coat treatment, dyeing treatment, light control treatment and the like can be performed.

〔Example〕

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The refractive index, Abbe number, weather resistance, releasability, and appearance of the obtained lens resin and lens performance test were measured by the following test methods.

Refractive index, Abbe number: Measured at 20 ° C. using a Pulflich refractometer.

Weather resistance: When a sunshine carbon arc lamp was equipped, the resin for the lens was set on the weather meter, and after 200 hours, the lens was taken out and the hue was compared with the resin for the lens before the test.

The evaluation criteria were no change (○), slight yellowing (△), and yellowing (x).

Releasability: After the polymerization was completed, a wedge made of Teflon was injected between the lens and the mold, and the mold was released without any resistance (抵抗), and the whole or part of the mold was not released (x).

Appearance: Observed visually.

Example 1 18.4 g (0.09 mol) of dithiodiethyl diisocyanate
And 8.0 g (0.06 mol) of 1,2,6-hexanetriol and 0.03 g of isopropyl acid phosphate were mixed and injected into a mold composed of a glass mold and a gasket. Next, the temperature was gradually raised from room temperature to 120 ° C., and the composition was cured by heating for 28 hours. After the polymerization, the lens was easily demoulded obtained lens is good surface accuracy is colorless and transparent, the refractive ▲ n ²⁰ _D
▼ = 1.57, Abbe number ▲ n ²⁰ _D ▼ = 44.

Examples 2 to 29 In the same manner as in Example 1, a lens was formed with the composition shown in Table 1. Table 1 shows the results of the performance test.

Comparative Examples 1 to 24 Table 2 was prepared in the same manner as in Example 1 except for the following mold treatment.
A lens was formed with the following composition. Table 2 shows the results.

No treatment: Glass mold used, no release agent used External release treatment: The inner surface of the glass mold was coated and baked with an external release agent YSR-6209 manufactured by Toshiba Silicone Co., Ltd. External release treatment Reuse: External release treatment Used once for polymerization, then used as is without treatment PP mold used: Polypropylene was used to make a mold by injection molding and used instead of a glass mold.

As is clear from the above results, in the case of using a crow or metal lens mold in the production of a polyurethane-based plastic lens, in a method using no mold release agent, the lens is released from the mold after polymerization. Did not. Also,
The method of using an external mold release agent impairs the surface accuracy, or when the master mold is used repeatedly,
Removal of the old mold release agent from the matrix and treatment with a new mold release agent were necessary, which was unsuitable as an industrial production method.

Also, in the method using a polypropylene lens mold instead of a glass or metal lens mold, the lens is released without using a release agent, but the surface accuracy required for the lens is impaired. .

According to the present invention, a polyurethane-based plastic lens is industrially manufactured without deteriorating the performance required as a lens by intentionally using an internal mold release agent which is not preferably used for manufacturing a lens. It is the first to disclose this.

〔The invention's effect〕

The polyurethane-based plastic lens obtained by using the casting polymerization method of the present invention is easy to release from a glass lens mold, and the obtained lens has high transparency, optical homogeneity, and good surface. Has accuracy.

The casting polymerization method of the present invention is a method for industrially obtaining a polyurethane plastic lens having excellent performance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location // B29K 75:00 105: 32 B29L 11:00 (31) Priority claim number Japanese Patent Application No. 63- 37523 (32) Priority Date February 22, 1988 (33) Priority Country Japan (JP) (31) Priority Claim Number Japanese Patent Application No. 63-37525 (32) Priority Date 1988 (1988) 2 March 22 (33) Countries claiming priority Japan (JP) Examiner Eiwa Hashimoto (56) References JP-A-1-163012 (JP, A) JP-A-1-295201 (JP, A) JP-A-62- 267316 (JP, A) JP-A-57-185315 (JP, A) JP-A-1-188511 (JP, A)

Claims (4)

(57) [Claims] An aliphatic polyisocyanate containing one or more sulfur atoms excluding an adduct modified product with a polythiol, a polyol containing no sulfur atom, a hydroxyl group-free polyol and a mercapto group. Internal separation into a mixture with one or more active hydrogen compounds selected from the group consisting of polythiols containing no sulfur atom and polythiols containing no hydroxyl group and containing at least one sulfur atom other than the mercapto group. A method for producing a high-refractive-index optical element, comprising casting and adding a molding agent. 2. An optical element obtained by the method according to claim 1. 3. An aliphatic polyisocyanate containing one or two or more sulfur atoms excluding a modified product of an adduct with polythiol, a polyol containing no sulfur atom, a hydroxyl group-free polyol and a mercapto group. Internal separation into a mixture with one or more active hydrogen compounds selected from the group consisting of polythiols containing no sulfur atom and polythiols containing no hydroxyl group and containing at least one sulfur atom other than the mercapto group. A method for producing a high-refractive-index plastic lens, characterized by adding a mold agent and performing casting polymerization. 4. A plastic lens obtained by the method according to claim 3.