Optical lens that contains thermoplastic resin

Abstract

According to the present invention, it is possible to provide an optical lens which contains a thermoplastic resin including a structural unit (A) derived from a monomer represented by general formula (1) and a structural unit (B) derived from BPPEF or BPEF represented by the following structural formula, and in which the mole ratio (A:B) of the structural unit (A) and the structural unit (B) is 5:95 to 79:21. (In general formula (1), R1-R4 each independently represent a hydrogen atom, a halogen atom, an optionally branched alkyl group having 1-10 carbon atoms, an alkoxy group having 1-10 carbon atoms, or an aryl group having 6-15 carbon atoms.)

Description

Optical lenses containing thermoplastic resins

[0001] The present invention relates to optical lenses comprising thermoplastic resins, and more particularly to optical lenses comprising polycarbonate resins.

[0002] Optical glass or optical resin is used as a material for optical lenses used in the optical systems of various cameras, such as cameras with integrated film, video cameras, etc. Optical glass is excellent in heat resistance, transparency, dimensional stability, chemical resistance, etc., but has problems such as high material costs, poor moldability, and low productivity.

[0003] On the other hand, optical lenses made of optical resins have the advantage that they can be mass-produced by injection molding, and polycarbonate, polyester carbonate, polyester resin, etc. are used as high refractive index materials for camera lenses.

[0004] When an optical resin is used as an optical lens, in addition to optical properties such as refractive index and Abbe number, it is required to have heat resistance, transparency, low water absorption, chemical resistance, low birefringence, moist heat resistance, etc. In particular, in recent years, there has been a demand for optical lenses with high refractive index and high heat resistance, and various resins have been developed (Patent Documents 1 to 5).

[0005] Furthermore, thermoplastic resins made from 2,2'-bis(2-hydroxyethoxy)-1,1'-binaphthalene have excellent optical properties and are useful as various optical materials (Patent Document 6). However, improvements in mass change rate and dimensional change rate have been required due to the wide range of molding processes and usage environments.

[0006] JP 2018-2893 A JP 2018-2894 A JP 2018-2895 A JP 2018-59074 A WO2017 / 078073 WO2014 / 073496

[0007] An object of the present invention is to provide an optical lens using a thermoplastic resin that has excellent optical properties such as refractive index and Abbe number, and also has excellent mass change rate and dimensional change rate.

[0008] As a result of extensive research aimed at solving the problems of the past, the present inventors have found that by blending a specific amount of a diol compound having a specific structure, an optical lens containing a thermoplastic resin that is excellent in optical properties such as refractive index and Abbe number, and also excellent in mass change rate and dimensional change rate, can be obtained, and have thereby completed the present invention.

[0009] That is, the present invention includes the following aspects: <1> An optical lens comprising a thermoplastic resin containing a constituent unit (A) derived from a monomer represented by the following general formula (1) and a constituent unit (B) derived from BPEF or BPPEF represented by the following structural formula, wherein the molar ratio (A:B) of the constituent unit (A) to the constituent unit (B) is 5:95 to 79:21: (In general formula (1), R １ ~R ４ each independently represents a hydrogen atom, a halogen atom, an optionally branched alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 15 carbon atoms. <2> The optical lens according to <1> above, wherein the thermoplastic resin further contains a structural unit (C) derived from BCFL represented by the following structural formula: <3> The optical lens according to <1> or <2>, wherein the proportion of the structural unit (A) in all structural units in the thermoplastic resin is 5 to 50 mol %. <4> The optical lens according to any one of <1> to <3>, wherein the proportion of the structural unit (B) in all structural units in the thermoplastic resin is 11 to 95 mol %. <5> The optical lens according to <2>, wherein the proportion of the structural unit (C) in all structural units in the thermoplastic resin is 0 to 50 mol %. <6> The optical lens according to any one of <1> to <5>, wherein the Tg of the thermoplastic resin is 120°C to 160°C. <7> The optical lens according to any one of <1> to <6>, wherein the refractive index (nD) of the thermoplastic resin is 1.600 to 1.660. <8> The optical lens according to any one of <1> to <7>, wherein the Abbe number of the thermoplastic resin is 21.0 to 27.0. <9> The optical lens according to any one of <1> to <8> above, wherein the thermoplastic resin has a mass change rate of 0.47% or less. <10> The optical lens according to any one of <1> to <9> above, wherein the thermoplastic resin has a dimensional change rate of 0.060% or less.

[0010] According to the present invention, an optical lens containing a thermoplastic resin having excellent optical properties such as refractive index and Abbe number, and also having excellent mass change rate and dimensional change rate, can be provided.

[0011] Hereinafter, the present invention will be described in detail by way of examples and synthesis examples. However, the present invention is not limited to the synthesis examples and examples exemplified, and can be carried out by any method as long as it does not significantly deviate from the content of the present invention.

[0012] <Thermoplastic Resin> The optical lens of the present invention comprises a thermoplastic resin containing a constituent unit (A) derived from a monomer represented by the following general formula (1) and a constituent unit (B) derived from BPEF (9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene) or BPPEF (9,9-bis[4-(2-hydroxyethoxy)-3-phenylphenyl]fluorene) represented by the following structural formula:

[0013] [Structural unit (A)] In general formula (1), R １ ~R ４ R each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms (preferably 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms) which may be branched, an alkoxy group having 1 to 10 carbon atoms (preferably 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms), or an aryl group having 6 to 15 carbon atoms (preferably 6 to 10 carbon atoms, more preferably 6 carbon atoms). １ ~R ４ and each independently represent a hydrogen atom, a methyl group, or a phenyl group. In the present invention, the monomer represented by general formula (1) is particularly preferably BPM (1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene) represented by the following structural formula. This compound is also called bisphenol M.

[0014] [Constituent unit (B)] In the present invention, the molar ratio (A:B) of the structural unit (A) to the structural unit (B) is 5:95 to 79:21, preferably 8:92 to 77:23, and more preferably 10:90 to 70:30. In the present invention, the BPEF and BPPEF used may be commercially available products or synthesized products.

[0015] [Structural Unit (C)] In a preferred embodiment of the present invention, the thermoplastic resin further contains a structural unit (C) derived from BCFL (biscresol fluorene) represented by the following structural formula. BCFL

[0016] In a preferred embodiment of the present invention, of all structural units in the thermoplastic resin, the proportion of the structural unit (A) is 5 to 50 mol%, and more preferably 8 to 48 mol%, the proportion of the structural unit (B) is 11 to 95 mol%, and more preferably 14 to 92 mol%, and the proportion of the structural unit (C) is 0 to 50 mol%, and more preferably 0 to 38 mol%.

[0017] The thermoplastic resin used in the optical lens of the present invention is not particularly limited and may be a polyester resin, a polycarbonate resin, a polyester carbonate resin, an epoxy resin, a polyurethane resin, a polyacrylic acid ester resin, a polymethacrylic acid ester resin, or the like. However, a polycarbonate resin, a polyester resin, or a polyester carbonate resin is preferred, and a polycarbonate resin is more preferred.

[0018] In a preferred embodiment of the present invention, the total proportion of the structural units (A), (B), and (C) in all structural units in the thermoplastic resin is preferably 80 to 100 mol %, more preferably 90 to 100 mol %, and particularly preferably 100 mol %. In other words, in addition to the structural units (A) to (C), the thermoplastic resin used in the present invention may contain structural units derived from aliphatic dihydroxy compounds and structural units derived from aromatic dihydroxy compounds that are generally used as structural units in polycarbonate resins and polyester carbonate resins, within a range that does not impair the effects of the present invention. Specific examples of aliphatic dihydroxy compounds include, but are not limited to, 1,4-cyclohexanedimethanol, tricyclodecane dimethanol, 1,3-adamantanedimethanol, 2,2-bis(4-hydroxycyclohexyl)-propane, 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, 2-(5-ethyl-5-hydroxymethyl-1,3-dioxan-2-yl)-2-methylpropan-1-ol, isosorbide, 1,3-propanediol, 1,4-butanediol, and 1,6-hexanediol. Examples of aromatic dihydroxy compounds include various compounds, particularly 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 4,4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)cycloalkane, bis(4-hydroxyphenyl)oxide, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)ketone, bisphenoxyethanolfluorene, and the like.

[0019] In one embodiment of the present invention, the thermoplastic resin preferably further contains a structural unit derived from at least one monomer selected from the following group of monomers: (In the above formula, R １ and R ２ each independently represents a hydrogen atom, a methyl group, or an ethyl group; R ３ and R ４ each independently represents a hydrogen atom, a methyl group, an ethyl group, or an alkylene glycol having 2 to 5 carbon atoms.

[0020] In a preferred embodiment of the polycarbonate resin of the present invention, impurities such as alcohol compounds such as phenolic compounds that may be generated as by-products during production, and diol components or carbonate diesters that remain unreacted may be present. The impurities, such as alcohol compounds such as phenolic compounds and carbonate diesters, may cause a decrease in strength or an odor when molded into a product, so it is preferable that the content of these impurities be as small as possible.

[0021] The content of residual phenolic compounds is preferably 3,000 ppm by mass or less, more preferably 1,000 ppm by mass or less, and particularly preferably 300 ppm by mass or less, based on 100% by mass of the polycarbonate resin. The content of residual diol components is preferably 1,000 ppm by mass or less, more preferably 100 ppm by mass or less, and particularly preferably 10 ppm by mass or less, based on 100% by mass of the polycarbonate resin. The content of residual carbonate diesters is preferably 1,000 ppm by mass or less, more preferably 100 ppm by mass or less, and particularly preferably 10 ppm by mass or less, based on 100% by mass of the polycarbonate resin. In particular, it is preferable that the contents of compounds such as phenol and t-butylphenol are low, and it is preferable that the contents of these compounds are within the above ranges.

[0022] The content of phenolic compounds remaining in the polycarbonate resin can be measured by a method of analyzing phenolic compounds extracted from the polycarbonate resin using gas chromatography. The content of alcoholic compounds remaining in the polycarbonate resin can also be measured by a method of analyzing alcoholic compounds extracted from the polycarbonate resin using gas chromatography. The content of diol components and carbonate diesters remaining in the polycarbonate resin can also be measured by a method of extracting these compounds from the polycarbonate resin and analyzing them using gas chromatography.

[0023] The contents of by-produced alcohol compounds such as phenolic compounds, diol components, and carbonate diesters may be reduced to an undetectable level, but from the viewpoint of productivity, they may be contained in small amounts within a range that does not impair the effects. Furthermore, small amounts can improve the plasticity of the resin when it is melted.

[0024] The content of each of the remaining phenolic compounds, diol components, and carbonate diesters may be, for example, 0.01 ppm by mass or more, 0.1 ppm by mass or more, or 1 ppm by mass or more, relative to 100% by mass of the polycarbonate resin. The content of the remaining alcoholic compounds may be, for example, 0.01 ppm by mass or more, 0.1 ppm by mass or more, or 1 ppm by mass or more, relative to 100% by mass of the polycarbonate resin.

[0025] The contents of by-produced alcohol compounds such as phenolic compounds, diol components, and carbonate diesters in the polycarbonate resin can be adjusted to fall within the above ranges by appropriately adjusting the polycondensation conditions and apparatus settings, and can also be adjusted by the conditions of the extrusion step after polycondensation.

[0026] For example, the amount of residual by-produced alcohol compounds such as phenolic compounds is related to the type of carbonate diester used in the polymerization of the polycarbonate resin, the polymerization reaction temperature, the polymerization pressure, etc. By adjusting these factors, the amount of residual by-produced alcohol compounds such as phenolic compounds can be reduced.

[0027] For example, when a polycarbonate resin is produced using a dialkyl carbonate such as diethyl carbonate, the molecular weight is difficult to increase, resulting in a low-molecular-weight polycarbonate, and the content of by-product alkyl alcohol compounds tends to be high. Such alkyl alcohols are highly volatile, and if they remain in the polycarbonate resin, the moldability of the resin tends to deteriorate. Furthermore, if a large amount of by-product alcohol compounds such as phenolic compounds remain, odor problems may occur during resin molding, or the cleavage reaction of the resin skeleton may progress during compounding, resulting in a decrease in molecular weight. Therefore, it is preferable that the content of by-product alcohol compounds remaining in the obtained polycarbonate resin be 3,000 ppm by mass or less relative to 100% by mass of the polycarbonate resin. The content of the remaining alcohol compounds is preferably 3,000 ppm by mass or less, more preferably 1,000 ppm by mass or less, and particularly preferably 300 ppm by mass or less, relative to 100% by mass of the polycarbonate resin.

[0028] The polycarbonate resin of a preferred embodiment of the present invention can be produced in the presence of a polycondensation catalyst selected from a basic compound catalyst, an ester exchange catalyst, and a mixed catalyst comprising both.

[0029] Examples of the basic compound catalyst include alkali metal compounds, alkaline earth metal compounds, and nitrogen-containing compounds.

[0030] Examples of alkali metal compounds include organic acid salts, inorganic salts, oxides, hydroxides, hydrides, and alkoxides of alkali metals. Specific examples include sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide, sodium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, sodium acetate, potassium acetate, cesium acetate, lithium acetate, sodium stearate, potassium stearate, cesium stearate, lithium stearate, sodium borohydride, sodium phenylborohydride, sodium benzoate, potassium benzoate, cesium benzoate, lithium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium phenylphosphate, disodium, dipotassium, dicesium, and dilithium salts of bisphenol A, and sodium, potassium, cesium, and lithium salts of phenol. From the viewpoints of catalytic effect, price, distribution volume, and influence on the color of the resin, sodium carbonate and sodium bicarbonate are preferred.

[0031] Examples of alkaline earth metal compounds include organic acid salts, inorganic salts, oxides, hydroxides, hydrides, and alkoxides of alkaline earth metal compounds. Specific examples include magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium hydrogen carbonate, calcium hydrogen carbonate, strontium hydrogen carbonate, barium hydrogen carbonate, magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, magnesium acetate, calcium acetate, strontium acetate, barium acetate, magnesium stearate, calcium stearate, calcium benzoate, and magnesium phenylphosphate.

[0032] Examples of the nitrogen-containing compound include quaternary ammonium hydroxides and their salts, amines, etc. Specific examples include quaternary ammonium hydroxides having an alkyl or aryl group, such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and trimethylbenzylammonium hydroxide; tertiary amines, such as triethylamine, dimethylbenzylamine, and triphenylamine; secondary amines, such as diethylamine and dibutylamine; primary amines, such as propylamine and butylamine; imidazoles, such as 2-methylimidazole, 2-phenylimidazole, and benzimidazole; and bases or basic salts, such as ammonia, tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, and tetraphenylammonium tetraphenylborate.

[0033] As the transesterification catalyst, zinc, tin, zirconium, and lead salts are preferably used, and these may be used alone or in combination, or may be used in combination with the above-mentioned alkali metal compounds or alkaline earth metal compounds.

[0034] Specific examples of the transesterification catalyst that can be used include zinc acetate, zinc benzoate, zinc 2-ethylhexanoate, tin(II) chloride, tin(IV) chloride, tin(II) acetate, tin(IV) acetate, dibutyltin dilaurate, dibutyltin oxide, dibutyltin dimethoxide, zirconium acetylacetonate, zirconium oxyacetate, zirconium tetrabutoxide, lead(II) acetate, and lead(IV) acetate.

[0035] These catalysts were used in an amount of 1×10 per mole of the total of the diol compounds. －９ ~1 x 10 －３ It is preferably used in a molar ratio of 1×10 －７ ~1 x 10 －４ Used in molar ratios.

[0036] <Physical Properties of Thermoplastic Resin> (1) Refractive Index (nD) In ​​one embodiment of the present invention, one of the characteristics of the thermoplastic resin is that it has a high refractive index, and the refractive index is preferably 1.600 to 1.660, and more preferably 1.610 to 1.650. In the present invention, the refractive index can be measured by the method described in the examples below.

[0037] (2) Abbe number (ν) In one embodiment of the present invention, the Abbe number of the thermoplastic resin is preferably 21.0 to 27.0, and more preferably 22.0 to 26.5. In the present invention, the Abbe number can be measured by the method described in the examples below.

[0038] (3) Glass Transition Temperature (Tg) In one embodiment of the present invention, one of the characteristics of the thermoplastic resin is high heat resistance, and the glass transition temperature (Tg) is preferably 120 to 160° C., more preferably 125 to 155° C. In the present invention, the glass transition temperature can be measured by the method described in the examples below.

[0039] (4) Weight Average Molecular Weight (Mw) in Polystyrene Equivalents In one embodiment of the present invention, the weight average molecular weight (Mw) in polystyrene equivalents of the thermoplastic resin is preferably 10,000 to 100,000, more preferably 20,000 to 70,000, and particularly preferably 30,000 to 60,000.

[0040] (5) Mass Change Rate (%) In one embodiment of the present invention, one of the characteristics of the thermoplastic resin is that it has a low mass change rate, and the mass change rate is preferably 0.47% or less, and more preferably 0.43% or less. There is no particular restriction on the lower limit, but it is about 0.20%. In the present invention, the mass change rate can be measured by the method described in the examples below.

[0041] (6) Dimensional Change Rate (%) In one embodiment of the present invention, one of the features of the thermoplastic resin is that it has a low dimensional change rate, and the dimensional change rate is preferably 0.060% or less, and more preferably 0.050% or less. There is no particular restriction on the lower limit, but it is about 0.010%. In the present invention, the dimensional change rate can be measured by the method described in the examples below.

[0042] <Thermoplastic Resin Composition> The optical lens of the present invention may contain a thermoplastic resin composition containing the above-described thermoplastic resin and additives. The thermoplastic resin composition of this embodiment can contain a resin other than the thermoplastic resin containing the above-described structural units (A) and (B), or the structural units (A), (B), and (C), as long as the desired effects of this embodiment are not impaired. Examples of such resins include, but are not limited to, at least one resin selected from the group consisting of polycarbonate resins, polyester resins, polyestercarbonate resins, (meth)acrylic resins, polyamide resins, polystyrene resins, cycloolefin resins, acrylonitrile-butadiene-styrene copolymer resins, vinyl chloride resins, polyphenylene ether resins, polysulfone resins, polyacetal resins, and methyl methacrylate-styrene copolymer resins. Various known resins can be used, and one type can be added alone or two or more types can be added in combination to the thermoplastic resin composition.

[0043] [Antioxidant] The thermoplastic resin composition preferably contains an antioxidant as the additive. The antioxidant preferably contains at least one of a phenolic antioxidant and a phosphite-based antioxidant. Examples of phenolic antioxidants include 1,3,5-tris(3,5-di-tert-butyl-4-hydroxyphenylmethyl)-2,4,6-trimethylbenzene, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine e-2,4,6(1H,3H,5H)-trione, 4,4',4''-(1-methylpropanyl-3-ylidene)tris(6-tert-butyl-m-cresol), 6,6'-di-tert-butyl-4,4'-butylidene-m-cresol, ocladecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, pentane, methyl ... Examples of the hydroxybenzoate include pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxospiro[5.5]undecane, and pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], and preferably pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].Phosphite antioxidants include 2-ethylhexyl diphenyl phosphite, isodecyl diphenyl phosphite, triisodecyl phosphite, triphenyl phosphite, 3,9-bis(octadecyloxy)-2,4,8,10-tetraoxy-3,9-diphosphaspiro[5.5]undecane, 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, 2,2'-methylenebis(4,6-di-tert-butylphenyl)2-ethylhexyl phosphite, Examples of the antioxidant include tris(2,4-di-tert-butylphenyl)phosphite, tris(nonylphenyl)phosphite, tetra-C12-15-alkyl(propane-2,2-diylbis(4,1-phenylene))bis(phosphite), and 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, and preferably 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane. As the antioxidant, any one of the above may be used alone, or a mixture of two or more may be used.

[0044] The antioxidant content in the thermoplastic resin composition is preferably 1 ppm by weight to 3,000 ppm by weight based on the total weight of the resin composition, more preferably 50 ppm by weight to 2,500 ppm by weight, even more preferably 100 ppm by weight to 2,000 ppm by weight, particularly preferably 150 ppm by weight to 1,500 ppm by weight, and even more preferably 200 ppm by weight to 1,200 ppm by weight.

[0045] [Release Agent] The thermoplastic resin composition preferably contains a release agent as the additive. Examples of the release agent include ester compounds, such as glycerin fatty acid esters such as mono- and diglycerides of glycerin fatty acid, glycol fatty acid esters such as propylene glycol fatty acid esters and sorbitan fatty acid esters, higher alcohol fatty acid esters, and full esters or mono-fatty acid esters of aliphatic polyhydric alcohols and aliphatic carboxylic acids. When an ester of aliphatic polyhydric alcohols and aliphatic carboxylic acids is used as the release agent, either a monoester or a full ester can be used, but other than a full ester, such as a monoester, may also be used. Specific examples of the release agent include the following.That is, sorbitan fatty acid esters such as sorbitan stearate, sorbitan laurate, sorbitan oleate, sorbitan trioleate, sorbitan tribehenate, sorbitan stearate, sorbitan tristearate, and sorbitan caprylate; propylene glycol fatty acid esters such as propylene glycol monostearate, propylene glycol monooleate, propylene glycol monobehenate, propylene glycol monolaurate, and propylene glycol monopalmitate; higher alcohol fatty acid esters such as stearyl stearate; glycerin monohydroxystearates such as glycerin monostearate and glycerin mono-12-hydroxystearate, glycerin monooleate, glycerin monobehenate, glycerin monocaprylate, glycerin monocaprate, and glycerin Examples of the monoglycerides include monoglycerides such as monolaurate, and mono-diglycerides such as glycerin monodistearate, glycerin monodistearate, glycerin monodibehenate, and glycerin monodiolate; acetylated monoglycerides of glycerin fatty acid esters such as glycerin diacetomonolaurate; organic acid monoglycerides of glycerin fatty acid esters such as citric acid fatty acid monoglyceride, succinic acid fatty acid monoglyceride, and diacetyltartaric acid fatty acid monoglyceride; and polyglycerin fatty acid esters such as diglycerin stearate, diglycerin laurate, diglycerin oleate, diglycerin monostearate, diglycerin monolaurate, diglycerin monomyristate, diglycerin monooleate, tetraglycerin stearate, decaglycerin laurate, decaglycerin oleate, and polyglycerin polyricinoleate.

[0046] The thermoplastic resin composition preferably contains 1 ppm by weight to 5,000 ppm by weight of the release agent based on the total weight of the resin composition, more preferably 50 ppm by weight to 4,000 ppm by weight, even more preferably 100 ppm by weight to 3,500 ppm by weight, particularly preferably 500 ppm by weight to 13,000 ppm by weight, and even more preferably 1,000 ppm by weight to 2,500 ppm by weight.

[0047] [Other Additives] In addition to the antioxidant and mold release agent described above, other additives may be added to the thermoplastic resin composition. For example, additives that may be contained in the thermoplastic resin composition include compounding agents, catalyst deactivators, heat stabilizers, plasticizers, fillers, UV absorbers, rust inhibitors, dispersants, antifoaming agents, leveling agents, flame retardants, lubricants, dyes, pigments, bluing agents, nucleating agents, and clarifying agents. The content of other additives other than the antioxidant and mold release agent in the thermoplastic resin composition is preferably 10 ppm by weight to 5.0% by weight, more preferably 100 ppm by weight to 2.0% by weight, and even more preferably 1000 ppm by weight to 1.0% by weight, but is not limited thereto. The above-mentioned additives may adversely affect transmittance, so it is preferable not to add them in excess; for example, the total amount added is within the above-mentioned range.

[0048] In the method for producing the thermoplastic resin composition used in the present invention, the catalyst may be removed or deactivated after the polymerization reaction to maintain thermal stability and hydrolytic stability, but deactivation is not necessarily required. When deactivating the catalyst, a known method for deactivating the catalyst by adding an acidic substance can be suitably carried out. Specific examples of the acidic substance include esters such as butyl benzoate; aromatic sulfonic acids such as p-toluenesulfonic acid; aromatic sulfonic acid esters such as butyl p-toluenesulfonate and hexyl p-toluenesulfonate; phosphoric acids such as phosphorous acid, phosphoric acid, and phosphonic acid; phosphite esters such as triphenyl phosphite, monophenyl phosphite, diphenyl phosphite, diethyl phosphite, di-n-propyl phosphite, di-n-butyl phosphite, di-n-hexyl phosphite, dioctyl phosphite, and monooctyl phosphite; triphenyl phosphate, diphenyl phosphate, monophenyl phosphate, dibutyl phosphate, and dioctyl phosphate. Suitable examples of suitable deactivators include phosphate esters such as phenylphosphonic acid and monooctyl phosphate; phosphonic acids such as diphenylphosphonic acid, dioctylphosphonic acid, and dibutylphosphonic acid; phosphonic acid esters such as diethyl phenylphosphonate; phosphines such as triphenylphosphine and bis(diphenylphosphino)ethane; boric acids such as boric acid and phenylboric acid; aromatic sulfonates such as tetrabutylphosphonium dodecylbenzenesulfonate; organic halides such as stearic acid chloride, benzoyl chloride, and p-toluenesulfonic acid chloride; alkyl sulfates such as dimethyl sulfate; and organic halides such as benzyl chloride. From the standpoint of the deactivator effect and stability to the resin, p-toluene or butyl sulfonate is particularly preferred. These deactivators are used in an amount of 0.01 to 50 times, preferably 0.3 to 20 times, the molar amount of the catalyst. Less than 0.01 times the molar amount of the catalyst results in insufficient deactivation effect, which is undesirable. Furthermore, if the amount of the deactivator is more than 50 times the amount of the catalyst, the heat resistance of the resin decreases and the molded product is likely to be discolored, which is not preferable. The kneading of the deactivator may be carried out immediately after the polymerization reaction is completed, or may be carried out after the polymerized resin is pelletized. In addition to the deactivator, other additives may also be added in the same manner.

[0049] <Optical Lens> The optical lens of the present invention contains the above-described thermoplastic resin or thermoplastic resin composition (hereinafter simply referred to as "resin composition"). When an optical lens containing the above-described resin composition is produced by injection molding, molding is preferably carried out under conditions of a cylinder temperature of 200 to 350°C and a mold temperature of 90 to 200°C. Molding is more preferably carried out under conditions of a cylinder temperature of 230 to 300°C and a mold temperature of 100 to 180°C. A particularly preferred mold temperature is 110 to 170°C. If the cylinder temperature is higher than 350°C, the resin composition will decompose and discolor, and if it is lower than 200°C, the melt viscosity will be high, making molding difficult. Furthermore, if the mold temperature is higher than 200°C, it will be difficult to remove a molded piece made of the resin composition from the mold. On the other hand, if the mold temperature is lower than 90°C, the resin will harden too quickly in the mold during molding, making it difficult to control the shape of the molded piece, and it will be difficult to sufficiently transfer the shape imprinted on the mold.

[0050] The optical lenses produced using the resin composition have a high refractive index and excellent heat resistance, and are therefore extremely useful in fields where expensive high refractive index glass lenses have traditionally been used, such as telescopes, binoculars, and television projectors. For example, in the case of smartphone lenses, lenses molded from a thermoplastic resin containing the above-mentioned structural units (A) and (B), or structural units (A), (B), and (C), or (In the above formula, R １ and R ２ each independently represents a hydrogen atom, a methyl group, or an ethyl group; R ３ and R ４ each independently represents a hydrogen atom, a methyl group, an ethyl group, or an alkylene glycol having 2 to 5 carbon atoms.) A lens molded from a resin containing a structural unit derived from any one of the monomers of the above formulas can be superimposed on the resin to be used as a lens unit.

[0051] The optical lens of the present invention is preferably implemented as an aspherical lens, if necessary. Since an aspherical lens can substantially eliminate spherical aberration with a single lens, it is not necessary to eliminate spherical aberration by combining multiple spherical lenses, which allows for weight reduction and reduced molding costs. Therefore, aspherical lenses are particularly useful as camera lenses, among other optical lenses.

[0052] Furthermore, because the optical lens of the present invention has high molding fluidity, it is particularly useful as a material for optical lenses that are thin, small, and have complex shapes. Specifically, the lens size preferably has a central thickness of 0.05 to 3.0 mm, more preferably 0.05 to 2.0 mm, and even more preferably 0.1 to 2.0 mm. The diameter is preferably 1.0 to 20.0 mm, more preferably 1.0 to 10.0 mm, and even more preferably 3.0 to 10.0 mm. Furthermore, the lens preferably has a meniscus shape, with one side convex and the other concave. The optical lens of the present invention can be molded by any method, such as mold molding, cutting, polishing, laser machining, electrical discharge machining, or etching. Among these, mold molding is more preferred in terms of production costs.

[0053] Examples of the present invention will be shown below together with comparative examples to explain the details of the invention, but the present invention is not limited to these examples.

[0054] 1) Refractive index (nD) Based on JIS B 7071-2:2018, a polycarbonate resin was molded into a V-shaped block to prepare a test specimen. The refractive index was measured at 23°C using the following refractometer: Shimadzu KPR-3000.

[0055] 2) Abbe number (ν) Using the same test piece (V-block) as used in the refractive index measurement, the refractive indexes at wavelengths of 486 nm, 589 nm, and 656 nm at 23°C were measured using the following refractometer, and the Abbe number was calculated using the following formula: Refractometer: KPR-3000 manufactured by Shimadzu Corporation ν=(nD-1) / (nF-nC) nD: refractive index at wavelength 589 nm nC: refractive index at wavelength 656 nm nF: refractive index at wavelength 486 nm

[0056] 3) Glass transition temperature (Tg): Measured according to JIS K7121-1987 using a differential scanning calorimeter with a temperature increase program of 10°C / min. Differential scanning calorimeter: X-DSC7000 manufactured by Hitachi High-Tech Science Corporation

[0057] 4) Mass Change Rate (%) Polycarbonate resin was dried at 120°C for 8 hours and injection molded to obtain a disk-shaped test piece with a diameter of 50 mm and a thickness of 2 mm. Molding conditions: Molding machine: Injection molding machine S-2000i30A (30 tons) manufactured by FANUC Corporation Molding conditions: Cylinder temperature: Tg of polycarbonate resin + 135°C Mold temperature: Tg of polycarbonate resin - 15°C The weight of the obtained test piece was measured and designated as M0. Next, after storing it for 72 hours in a constant temperature and humidity chamber set at a temperature of 85°C and a humidity of 85%, the weight of the test piece was measured and designated as M1. The mass change rate (%) was calculated using the following formula: Mass change rate (%) = (M1 - M0) / M0 x 100 M1: Mass of the test piece after 72 hours of storage at a temperature of 85°C and a humidity of 85% M0: Mass of the test piece before 72 hours of storage at a temperature of 85°C and a humidity of 85%

[0058] 5) Dimensional Change Rate (%) Polycarbonate resin was dried at 120°C for 8 hours and injection molded to obtain a disk-shaped test piece with a diameter of 50 mm and a thickness of 2 mm. Molding machine: FANUC Corporation injection molding machine S-2000i30A (30 tons) Molding conditions: Cylinder temperature: Tg of polycarbonate resin + 135°C Mold temperature: Tg of polycarbonate resin - 15°C The length of the obtained test piece from the molding gate opening to the opposite gate opening was measured using an image dimension measuring device and designated L0. Next, the test piece was stored in a constant temperature and humidity chamber set at a temperature of 85°C and a humidity of 85% for 72 hours, after which the length of the test piece from the molding gate opening to the opposite gate opening was measured using an image dimension measuring device and designated L1. The dimensional change rate (%) was calculated using the following formula. Dimensional change rate (%) = (L1 - L0) / L0 x 100 L1: Length from molding gate opening to opposite gate opening of test piece after 72 hours storage at 85°C temperature and 85% humidity L0: Length from molding gate opening to opposite gate opening of test piece before 72 hours storage at 85°C temperature and 85% humidity Image dimension measuring instrument: Image dimension measuring instrument head LM-1100 manufactured by Keyence Corporation

[0059] Example 1 As raw materials, 8000 g (18.24 mol) of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (BPEF) represented by the following structural formula, 550 g (1.59 mol) of 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene (BPM) represented by the following structural formula, 4375 g (20.42 mol) of diphenyl carbonate (DPC), and 1.2 ml (2.2 × 10) of a 0.10 mol / L aqueous sodium hydrogen carbonate solution were used. －４ mole, i.e., 6.0 × 10 per mole of the total of dihydroxy compounds －６(mol) was placed in a 50-liter reactor equipped with a stirrer and distillation device, and heated to 215°C over 1 hour under a nitrogen atmosphere of 760 Torr with stirring. The reduced pressure was then adjusted to 150 Torr over 15 minutes, and the mixture was maintained at 215°C and 150 Torr for 20 minutes to carry out a transesterification reaction. The mixture was then heated to 240°C at a rate of 37.5°C / hr and maintained at 240°C and 150 Torr for 10 minutes. The mixture was then adjusted to 120 Torr over 10 minutes and maintained at 240°C and 120 Torr for 70 minutes. The mixture was then adjusted to 100 Torr over 10 minutes and maintained at 240°C and 100 Torr for 10 minutes. The mixture was then reduced to 1 Torr or less over 40 minutes, and the polymerization reaction was carried out with stirring for 10 minutes under conditions of 240°C and 1 Torr or less. After the reaction was completed, nitrogen was introduced into the reactor, the reactor was pressurized, and the produced polycarbonate resin was pelletized and removed. The evaluation results of the obtained resin are shown in Table 1 below. The obtained resin was dried at 100°C for 12 hours or more in an ADVANTEC constant temperature air dryer DRM420DD, and then injection molded in a FANUC injection molding machine S-2000i30A at a cylinder temperature of 260°C and a mold temperature 10°C lower than the glass transition temperature of the resin, to obtain a lens with a diameter of 5 mm.

[0060]

[0061] (Examples 2 to 7, Comparative Examples 1 to 5) Polycarbonate resins were obtained in the same manner as in Example 1, except that the raw materials shown in Table 2 below were used. The evaluation results of the obtained resins are shown in Table 1 below. In Comparative Examples 2 to 4, the Tg was low and the mass change rate and dimensional change rate could not be measured.

[0062]

Claims

1. An optical lens comprising a thermoplastic resin containing a structural unit (A) derived from a monomer represented by the following general formula (1) and a structural unit (B) derived from BPEF or BPPEF represented by the following structural formula: The optical lens as described above, wherein the molar ratio (A:B) of the structural unit (A) to the structural unit (B) is 5:95 to 79:

21. 【Chemical 1】 (In general formula (1), R １ ~R ４ each independently represents a hydrogen atom, a halogen atom, an optionally branched alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 15 carbon atoms. 【Chemistry 2】

2. 2. The optical lens according to claim 1, wherein the thermoplastic resin further contains a structural unit (C) derived from BCFL represented by the following structural formula: 【Chemistry 3】

3. 3. The optical lens according to claim 1, wherein the proportion of the structural unit (A) in all structural units in the thermoplastic resin is 5 to 50 mol %.

4. 3. The optical lens according to claim 1, wherein the proportion of the structural unit (B) in all structural units in the thermoplastic resin is 11 to 95 mol %.

5. 3. The optical lens according to claim 2, wherein the proportion of the structural unit (C) in all structural units in the thermoplastic resin is 0 to 50 mol %.

6. 3. The optical lens according to claim 1, wherein the thermoplastic resin has a Tg of 120°C to 160°C.

7. 3. The optical lens according to claim 1, wherein the refractive index (nD) of the thermoplastic resin is 1.600 to 1.

660.

8. 3. The optical lens according to claim 1, wherein the thermoplastic resin has an Abbe number of 21.0 to 27.

0.

9. 3. The optical lens according to claim 1, wherein the mass change rate of the thermoplastic resin is 0.47% or less.

10. 3. The optical lens according to claim 1, wherein the thermoplastic resin has a dimensional change rate of 0.060% or less.

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