Thermoplastic resin and optical member containing same

Abstract

The purpose of the present invention is to provide: a polycarbonate resin which can satisfy all of a refractive index, an Abbe number, heat resistance, and birefringence; and an optical member containing the same. This thermoplastic resin contains repeating units represented by formula (1), formula (2) and formula (3), contains 60 mol% or more of repeating units represented by formula (1), and has a refractive index of more than 1.600 and not more than 1.660. (In formula (1), R1 to R4 each independently denote a hydrogen atom or a hydrocarbon group having 1-10 carbon atoms.) (In formula (3), n falls within the range 1-8, R5 and R6 each independently denote a hydrogen atom or a hydrocarbon group having 1-10 carbon atoms, and R7 denotes a hydrogen atom or an alkyl group having 1-3 carbon atoms.)

Description

[Technical field]

[0001] The present invention relates to a novel thermoplastic resin and an optical member, particularly an optical lens, formed therefrom. [Background technology]

[0002] The present invention relates to a thermoplastic resin and an optical member containing the same. There is a strong demand for low birefringence and improved aberration correction capabilities in plastic imaging lenses used in devices such as smartphones. Conventionally, such imaging lenses have corrected aberrations by combining multiple lenses with different optical properties (refractive index, Abbe number) and lens shapes.

[0003] In recent years, lens units have been created more and more often by combining high refractive index, low Abbe number resins with cycloolefin-based low refractive index, high Abbe number resins. In order to create even higher performance lens units, the use of medium refractive index, medium Abbe number resins has expanded the scope of lens design and made it possible to fine-tune the lens to achieve advanced performance. As a result, there has been an increase in demand for medium refractive index, medium Abbe number resins with a refractive index of around 1.600 to 1.660.

[0004] However, when using optical transparent resins as optical lenses, in addition to the refractive index and Abbe number, transparency, heat resistance, and low birefringence are required, so the places where they can be used are limited by the balance of the resin's properties. For example, polystyrene has low heat resistance and high birefringence, poly-4-methylpentene has low heat resistance, polymethyl methacrylate has a low glass transition temperature and low heat resistance, and polycarbonate made from bisphenol A has high birefringence, so the places where they can be used are limited.

[0005] Patent Documents 1 to 3 describe polycarbonate resin compositions containing a compound having a fluorene skeleton. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 10-101786 [Patent Document 2] International Publication No. 2017 / 010318 [Patent Document 3] JP 2020-19922 A Summary of the Invention [Problem to be solved by the invention]

[0007] The polycarbonate resins described in Patent Documents 1 and 2 are copolymer resins of a compound having a fluorene skeleton and one other component, and while it is possible to satisfy any one of the refractive index, Abbe number, heat resistance, and birefringence, it is difficult to satisfy all of them.

[0008] The polycarbonate resin described in Patent Document 3 has a low content of a compound having a fluorene skeleton, and therefore, although it is possible to satisfy any one of the refractive index, Abbe number, heat resistance, and birefringence, it is difficult to satisfy all of them.

[0009] Therefore, an object of the present invention is to provide a polycarbonate resin that satisfies all of the requirements for refractive index, Abbe number, heat resistance, and birefringence, and an optical member containing the same. [Means for solving the problem]

[0010] The present inventors have found that the above problems can be solved by the present invention having the following aspects.

[0011] <Aspect 1> A thermoplastic resin containing repeating units represented by formula (1), formula (2) and formula (3), in which the repeating units represented by formula (1) account for 60 mol % or more and the refractive index is greater than 1.600 and less than 1.660.

[0012] [ka] (In formula (1), R 1 ~R 4 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms.

[0013] [ka]

[0014] [ka] (In formula (3), n is in the range of 1 to 8, and R 5 and R 6 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms; R 7 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

[0015] <Aspect 2> 2. The thermoplastic resin according to aspect 1, wherein the repeating unit of formula (1) is 60 mol % or more and 80 mol % or less.

[0016] <Aspect 3> R in the above formula (1) 1 ~R 4 is a hydrogen atom.

[0017] <Aspect 4> The thermoplastic resin according to any one of aspects 1 to 3, wherein the repeating unit of formula (3) is a repeating unit derived from 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol.

[0018] <Aspect 5> The thermoplastic resin according to any one of aspects 1 to 4, having a glass transition temperature of 130 to 160°C.

[0019] <Aspect 6> The absolute value of orientation birefringence is 3.0×10 -3 6. The thermoplastic resin according to any one of aspects 1 to 5, wherein:

[0020] Seventh Aspect The absolute value of orientation birefringence is 1.0×10 -3 6. The thermoplastic resin according to any one of aspects 1 to 5, wherein:

[0021] Eighth Aspect A thermoplastic resin according to any one of aspects 1 to 7, having an Abbe number of 24.0 to 29.0.

[0022] 9. Aspect 9 An optical member comprising the thermoplastic resin according to any one of the first to eighth embodiments.

[0023] <Aspect 10> 10. The optical member according to embodiment 9, which is an optical lens.

[0024] <Thermoplastic resin> The thermoplastic resin of the present invention contains repeating units represented by the above formulas (1), (2) and (3), and the repeating unit represented by the above formula (1) accounts for 60 mol % or more. The thermoplastic resin of the present invention has a refractive index of more than 1.600 and not more than 1.660.

[0025] The present inventors have found that a thermoplastic resin containing 60 mol % or more of the repeating unit represented by the above formula (1) exhibits a medium refractive index and a medium Abbe number that are useful for producing optical lens units. Furthermore, they have found that copolymerization with the above formulas (2) and (3) satisfies not only the refractive index and Abbe number but also heat resistance and birefringence, which led to the present application.

[0026] <Thermoplastic resin structure> R in the above formula (1) 1 ~R 4 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and examples of the hydrocarbon group include an alkyl group, a cycloalkyl group, and an aryl group.

[0027] Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a t-butyl group, with a methyl group and an ethyl group being preferred.

[0028] Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a bicyclo[1.1.1]pentanyl group.

[0029] Examples of the aryl group include a phenyl group, a tolyl group, a naphthyl group, and a xylyl group, with the phenyl group being preferred.

[0030] R 1 ~R 4 are each independently preferably a hydrogen atom, a methyl group, or a phenyl group, more preferably a hydrogen atom or a phenyl group; R 1 and R 2 are each independently a hydrogen atom or a phenyl group, R 3 and R 4 is more preferably a hydrogen atom.

[0031] The repeating unit represented by the above formula (1) is preferably a repeating unit derived from 9,9-bis(4-(hydroxyethoxy)phenyl)fluorene or 9,9-bis(4-(hydroxyethoxy)-3-phenylphenyl)fluorene, and more preferably a repeating unit derived from 9,9-bis(4-(hydroxyethoxy)phenyl)fluorene.

[0032] The thermoplastic resin of the present invention may contain the repeating unit of the above formula (1) in an amount of preferably 60 mol% to 99 mol%, more preferably 60 mol% to 85 mol%, even more preferably 60 mol% to 80 mol%, particularly preferably 65 mol% to 80 mol%, and most preferably 70 mol% to 80 mol%.

[0033] When the repeating unit represented by the above formula (1) is in the above range, the refractive index and birefringence can be satisfied.

[0034] The repeating unit represented by the above formula (2) is a repeating unit derived from 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane.

[0035] The thermoplastic resin of the present invention may contain the repeating unit of the above formula (2) in an amount of preferably 1 mol % to 35 mol %, more preferably 5 mol % to 30 mol %, further preferably 10 mol % to 25 mol %, and particularly preferably 10 mol % to 20 mol %.

[0036] In the above formula (3), n represents a number ranging from 1 to 8, preferably 1 to 5, more preferably 1 to 3, and even more preferably 3. 5 , R 6 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and examples of the hydrocarbon group include an alkyl group, a cycloalkyl group, and an aryl group.

[0037] Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a t-butyl group, with a methyl group and an ethyl group being preferred.

[0038] Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a bicyclo[1.1.1]pentanyl group.

[0039] Examples of the aryl group include a phenyl group, a tolyl group, a naphthyl group, and a xylyl group, and the phenyl group is preferable.

[0040] R 5 , R 6 are each independently preferably a hydrogen atom, a methyl group, or a phenyl group, more preferably a hydrogen atom or a phenyl group, and even more preferably a hydrogen atom.

[0041] R 7represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, preferably a methyl group or an ethyl group, more preferably a methyl group.

[0042] R 5 , R 6 When the substituent of R is as above, the amount of the above formula (3) can be increased without significantly increasing the refractive index, so that the heat resistance can be improved. In addition, when the substituent of R is as above, the heat resistance can be further improved.

[0043] The repeating unit represented by the above formula (3) is preferably a repeating unit derived from 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol, 4,4'-cyclohexylidene bisphenol, or 4,4'-(3-methylcyclohexylidene)bisphenol, and more preferably a repeating unit derived from 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol or 4,4'-cyclohexylidene bisphenol.

[0044] The thermoplastic resin of the present invention may contain the repeating unit of the above formula (3) in an amount of preferably 1 mol % to 35 mol %, more preferably 5 mol % to 30 mol %, further preferably 5 mol % to 20 mol %, and particularly preferably 5 mol % to 15 mol %.

[0045] When the repeating units represented by the above formulas (2) and (3) are within the above ranges, the refractive index, Abbe number, heat resistance, and birefringence can be satisfied.

[0046] The thermoplastic resin of the present invention may contain repeating units other than the repeating units represented by the above formulas (1), (2) and (3) within the scope of obtaining the advantageous effects of the present invention. Examples of dihydroxy compounds that provide such repeating units include ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol, tricyclo[5.2.1.02,6]decanedimethanol, cyclohexane-1,4-dimethanol, decalin-2,6-dimethanol, norbornane dimethanol, pentacyclopentadecanedimethanol, cyclopentane-1,3-dimethanol, isosorbide, isomannide, isoidide, hydrochloride, and the like. Examples of such repeating units include quinone, resorcinol, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, bis(4-hydroxyphenyl)diphenylmethane, 1,3-bis(2-(4-hydroxyphenyl)-2-propyl)benzene, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfide, biphenol, bisphenolfluorene, and biscresolfluorene. Such repeating units may account for 10 mol % or less of the total repeating units.

[0047] It is preferable that the thermoplastic resin of the present invention does not have a phenolic hydroxyl group at the terminal. That is, when a monomer that produces a repeating unit represented by the above formula (3) is polymerized and bonded to the terminal, the terminal group becomes a phenolic hydroxyl group. Therefore, it is preferable to use, for example, an excess amount of a carbonic acid diester over the dihydroxy compound used as the raw material during polymerization to convert the terminal into a phenyl group, thereby reducing the amount of terminal phenolic hydroxyl groups in the thermoplastic resin. The ratio of terminal phenolic hydroxyl groups is Terminal phenolic hydroxyl group ratio = (terminal phenolic hydroxyl group amount / total terminal amount) x 100 It should be noted that all of the terminals consist of a terminal phenolic hydroxyl group, a terminal alcoholic hydroxyl group, and a terminal phenyl group.

[0048] Although not limited to this example, specifically, the terminal phenolic hydroxyl group ratio can be determined by the following method. (1) The terminal phenolic hydroxyl group of the thermoplastic resin 1 Observe by H NMR measurement, take the integral of the relevant peak and set this as 1. At the same time, calculate the integral intensity (A) of one proton of the fluorene structure from the integrated intensity of the peaks at positions 4 and 5 of the fluorene structure derived from the above formula (1). Naturally, when no peak of a terminal phenolic hydroxyl group is observed, the ratio of the terminal phenolic hydroxyl group is zero.

[0049] (2) The average degree of polymerization of the thermoplastic resin is calculated from the number average molecular weight obtained by GPC measurement of the thermoplastic resin and the molecular weight and molar ratio of each repeating unit, and the terminal 1 The integrated intensity (B) in the H NMR spectrum is calculated using the following formula. (B)=(A)×100×2 / ([mol% of formula (1)]×average degree of polymerization)

[0050] (3) The terminal phenolic hydroxyl group ratio is calculated as 1 / (B) × 100. The ratio of terminal phenolic hydroxyl groups to all terminals of the thermoplastic resin of the present invention is preferably 30% or less, 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, 1% or less, or 0.5% or less.

[0051] <Thermoplastic resin physical properties> The refractive index of the thermoplastic resin of the present invention, when measured at a temperature of 20°C and a wavelength of 587.56 nm, is preferably more than 1.600 and not more than 1.660, more preferably more than 1.600 and not more than 1.650, even more preferably more than 1.600 and not more than 1.630, particularly preferably more than 1.600 and not more than 1.620, and particularly preferably more than 1.610 and not more than 1.620.

[0052] The Abbe number of the thermoplastic resin of the present invention is preferably 24.0 to 29.0, more preferably 25.0 to 29.0, further preferably 24.0 to 28.0, particularly preferably 24.0 to 28.0, and most preferably 24.0 to 27.0.

[0053] Here, the Abbe number (νd) is calculated from the refractive indexes at a temperature of 20° C. and wavelengths of 486.13 nm, 587.56 nm, and 656.27 nm using the following formula. νd=(nd-1) / (nF-nC) nd: refractive index at a wavelength of 587.56 nm, nF: refractive index at a wavelength of 486.13 nm, nC: refers to the refractive index at a wavelength of 656.27 nm.

[0054] The specific viscosity of the thermoplastic resin of the present invention is preferably 0.12 to 0.32, and more preferably 0.18 to 0.30. When the specific viscosity is 0.12 to 0.32, an excellent balance between moldability and strength is achieved.

[0055] The specific viscosity is measured by dissolving 0.7 g of the thermoplastic resin in 100 ml of methylene chloride, measuring the specific viscosity (ηSP) at 20° C. with an Ostwald viscometer, and calculating from the following formula. ηSP=(t-t0) / t0 [t0 is the number of seconds it takes for methylene chloride to fall, and t is the number of seconds it takes for the sample solution to fall]

[0056] The absolute value of the orientation birefringence (Δn) of the thermoplastic resin of the present invention is 3.0×10 -3 It is preferable that the value is less than 2.0×10 -3 More preferably, it is 1.0×10 -3 More preferably, it is 0.6×10 or less. -3 It is particularly preferable that the value is 0.4×10 or less. -3 Most preferably, it is:

[0057] If the absolute value of the orientation birefringence is below the above range, it does not have a significant effect on chromatic aberration, and the performance can be maintained as per the optical design. The orientation birefringence is measured at a wavelength of 589 nm after a 100 μm thick cast film obtained from the thermoplastic resin is stretched twice at Tg+10°C.

[0058] The thermoplastic resin of the present invention preferably has a total light transmittance at a thickness of 1 mm of 80% or more, more preferably 85% or more, and particularly preferably 88% or more.

[0059] The saturated water absorption of the thermoplastic resin of the present invention may be 0.10% to 0.70%, 0.20% to 0.70%, or 0.30% to 0.65%.

[0060] The glass transition temperature of the thermoplastic resin of the present invention is preferably from 130°C to 160°C, more preferably from 135°C to 55°C, and particularly preferably from 140°C to 150°C.

[0061] Examples of the thermoplastic resin of the present invention include polycarbonates containing the carbonate structures represented by formula (1), formula (2), and formula (3) in the repeating units, and polyester carbonates containing the repeating units represented by formula (1), formula (2), and formula (3) and ester structures other than these in the repeating units. Among these, polycarbonates are preferred in terms of heat resistance and moist heat resistance.

[0062] <Production method of polycarbonate resin> The polycarbonate resin of the present invention is produced by a reaction means known per se for producing a normal polycarbonate resin, for example, a method of reacting a dihydroxy compound with a carbonate precursor such as a carbonic acid diester. Next, the basic means for these production methods will be briefly described.

[0063] The transesterification reaction using a carbonic acid diester as a carbonate precursor is carried out by a method in which a predetermined ratio of a dihydroxy component is heated and stirred with a carbonic acid diester under an inert gas atmosphere, and the alcohol or phenol produced is distilled off. The reaction temperature varies depending on the boiling point of the alcohol or phenol produced, but is usually in the range of 120 to 300°C. The reaction is completed by reducing the pressure from the beginning of the reaction to distill off the alcohol or phenol produced. In addition, a terminal terminator, an antioxidant, etc. may be added as necessary.

[0064] The carbonic acid diester used in the transesterification reaction may be an ester of an aryl group or an aralkyl group having 6 to 12 carbon atoms, which may be substituted. Specific examples include diphenyl carbonate, ditolyl carbonate, bis(chlorophenyl) carbonate, and m-cresyl carbonate. Among these, diphenyl carbonate is particularly preferred. The amount of diphenyl carbonate used is preferably 0.95 to 1.10 mol, more preferably 0.98 to 1.04 mol, relative to 1 mol of the total of the dihydroxy compounds.

[0065] In the melt polymerization method, a polymerization catalyst can be used to increase the polymerization rate. Examples of such a polymerization catalyst include alkali metal compounds, alkaline earth metal compounds, and nitrogen-containing compounds.

[0066] As such compounds, organic acid salts, inorganic salts, oxides, hydroxides, hydrides, alkoxides, quaternary ammonium hydroxides, etc. of alkali metals or alkaline earth metals are preferably used, and these compounds can be used alone or in combination.

[0067] Examples of alkali metal compounds include sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide, sodium hydrogen carbonate, 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 benzoate, potassium benzoate, cesium benzoate, lithium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium phenylphosphate, disodium salt, dipotassium salt, dicesium salt, and dilithium salt of bisphenol A, and sodium, potassium, cesium, and lithium salts of phenol.

[0068] Examples of the alkaline earth metal compound include magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, magnesium diacetate, calcium diacetate, strontium diacetate, barium diacetate, and the like.

[0069] Examples of the nitrogen-containing compound include quaternary ammonium hydroxides having an alkyl or aryl group, such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and trimethylbenzylammonium hydroxide. Examples of the base or basic salt include tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, and tetraphenylammonium tetraphenylborate.

[0070] Other transesterification catalysts include salts of zinc, tin, zirconium, lead, titanium, germanium, antimony, and osmium, such as zinc acetate, zinc benzoate, zinc 2-ethylhexanoate, tin chloride (II), tin chloride (IV), tin acetate (II), tin acetate (IV), dibutyltin dilaurate, dibutyltin oxide, dibutyltin dimethoxide, zirconium acetylacetonate, zirconium oxyacetate, zirconium tetrabutoxide, lead acetate (II), lead acetate (IV) titanium tetrabutoxide (IV), etc. may be used. The catalysts used in WO 2011 / 010741 and JP 2017-179323 A may also be used.

[0071] Furthermore, a catalyst consisting of aluminum or a compound thereof and a phosphorus compound may be used, in which case the amount is preferably 80 μmol to 1000 μmol, more preferably 90 μmol to 800 μmol, and even more preferably 100 μmol to 600 μmol per 1 mol of the dihydroxy component.

[0072] Examples of aluminum salts include organic and inorganic salts of aluminum. Examples of aluminum organic salts include aluminum carboxylates, specifically aluminum formate, aluminum acetate, aluminum propionate, aluminum oxalate, aluminum acrylate, aluminum laurate, aluminum stearate, aluminum benzoate, aluminum trichloroacetate, aluminum lactate, aluminum citrate, and aluminum salicylate. Examples of aluminum inorganic salts include aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, aluminum carbonate, aluminum phosphate, and aluminum phosphonate. Examples of aluminum chelate compounds include aluminum acetylacetonate, aluminum acetylacetate, aluminum ethylacetoacetate, and aluminum ethylacetoacetate diisopropoxide.

[0073] Examples of phosphorus compounds include phosphonic acid compounds, phosphinic acid compounds, phosphine oxide compounds, phosphonous acid compounds, phosphineous acid compounds, and phosphine compounds. Among these, phosphonic acid compounds, phosphinic acid compounds, and phosphine oxide compounds are particularly preferred, and phosphonic acid compounds are particularly preferred.

[0074] The amount of these polymerization catalysts used is preferably 0.1 μmol to 500 μmol, more preferably 0.5 μmol to 300 μmol, and further preferably 1 μmol to 100 μmol, per 1 mol of the dihydroxy component.

[0075] A catalyst deactivator can also be added in the later stage of the reaction. Known catalyst deactivators can be effectively used as the catalyst deactivator, and among these, ammonium salts and phosphonium salts of sulfonic acid are preferred. Furthermore, salts of dodecylbenzenesulfonic acid such as tetrabutylphosphonium dodecylbenzenesulfonate and salts of paratoluenesulfonic acid such as tetrabutylammonium paratoluenesulfonate are preferred.

[0076] As the ester of sulfonic acid, methyl benzenesulfonate, ethyl benzenesulfonate, butyl benzenesulfonate, octyl benzenesulfonate, phenyl benzenesulfonate, methyl paratoluenesulfonate, ethyl paratoluenesulfonate, butyl paratoluenesulfonate, octyl paratoluenesulfonate, phenyl paratoluenesulfonate, etc. are preferably used. Among them, tetrabutylphosphonium dodecylbenzenesulfonate is most preferably used.

[0077] When at least one polymerization catalyst selected from alkali metal compounds and / or alkaline earth metal compounds is used, the amount of these catalyst deactivators used is preferably 0.5 to 50 mol, more preferably 0.5 to 10 mol, and even more preferably 0.8 to 5 mol, per mol of the catalyst.

[0078] <Production method of polyester carbonate resin> The thermoplastic resin of the present invention may be a polyester carbonate resin, which is produced by a reaction means known per se for producing a normal polyester carbonate resin, for example, a method of subjecting a dihydroxy compound to a polycondensation reaction with a carbonate precursor such as a carbonic acid diester and a dicarboxylic acid or an ester-forming derivative thereof.

[0079] In the reaction of a dihydroxy compound, a dicarboxylic acid or its acid chloride with phosgene, the reaction is carried out in a non-aqueous system in the presence of an acid binder and a solvent. Examples of the acid binder include pyridine, dimethylaminopyridine, and tertiary amines. Examples of the solvent include halogenated hydrocarbons such as methylene chloride and chlorobenzene. It is desirable to use an end terminator such as phenol or p-tert-butylphenol as a molecular weight regulator. The reaction temperature is usually 0 to 40°C, and the reaction time is preferably several minutes to 5 hours.

[0080] In the transesterification reaction, a dihydroxy compound, a dicarboxylic acid or its diester, and a bisaryl carbonate are mixed in an inert gas atmosphere and reacted under reduced pressure at a temperature of usually 120 to 350°C, preferably 150 to 300°C. The degree of reduced pressure is changed stepwise, and finally, the pressure is reduced to 133 Pa or less to distill off the generated alcohols from the system. The reaction time is usually about 1 to 4 hours. In addition, a polymerization catalyst can be used in the transesterification reaction to promote the reaction. As such a polymerization catalyst, an alkali metal compound, an alkaline earth metal compound, or a heavy metal compound is preferably used as a main component, and a nitrogen-containing basic compound is preferably used as a secondary component as necessary.

[0081] Examples of the alkali metal compounds include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, lithium hydrogen carbonate, sodium carbonate, potassium carbonate, lithium carbonate, sodium acetate, potassium acetate, lithium acetate, sodium stearate, potassium stearate, lithium stearate, sodium salt, potassium salt, lithium salt of bisphenol A, sodium benzoate, potassium benzoate, lithium benzoate, etc. Examples of the alkaline earth metal compounds include calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, calcium hydrogen carbonate, barium hydrogen carbonate, magnesium hydrogen carbonate, strontium hydrogen carbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate, strontium stearate, etc.

[0082] Examples of the nitrogen-containing basic compound include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylamine, triethylamine, dimethylbenzylamine, triphenylamine, and dimethylaminopyridine.

[0083] As other transesterification catalysts, the catalysts exemplified as the transesterification catalyst in the above-mentioned method for producing a polycarbonate can be similarly used.

[0084] When the thermoplastic resin of the present invention is a polyester carbonate, the catalyst may be removed or deactivated after the polymerization reaction is completed in order to maintain thermal stability and hydrolytic stability. In general, a method of deactivating the catalyst by adding a known acidic substance is preferably carried out. Specific examples of these substances 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, phosphoric acid 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, and esters such as triphenyl phosphate, diphenyl phosphate, monophenyl phosphate, dibutyl phosphate, and dioctyl phosphate. Suitable examples of the deactivating agent include phosphate esters such as monooctyl phosphate, diphenylphosphonic acid, dioctylphosphonic acid, dibutylphosphonic acid, and other phosphonic acids, phosphonic acid esters such as diethyl phenylphosphonate, phosphines such as triphenylphosphine and bis(diphenylphosphino)ethane, boric acid, phenylboric acid, and other borates, 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. These deactivating agents are used at a ratio of 0.01 to 50 mol, preferably 0.3 to 20 mol, relative to 1 mol of the catalyst. If the amount of the deactivating agent is less than 0.01 mol relative to 1 mol of the catalyst, the deactivating effect is insufficient, which is not preferable. If the amount of the deactivating agent is more than 50 mol relative to 1 mol of the catalyst, the heat resistance decreases and the molded body is easily colored, which is not preferable.

[0085] After the catalyst is deactivated, a step of removing low boiling point compounds in the thermoplastic resin by volatilization at a pressure of 13.3 to 133 Pa and a temperature of 200 to 320° C. may be provided.

[0086] <Thermoplastic resin composition> The thermoplastic resin of the present invention can be used as a resin composition by appropriately adding additives such as a mold release agent, a heat stabilizer, an ultraviolet absorber, a bluing agent, an antistatic agent, a flame retardant, a plasticizer, a filler, an antioxidant, a light stabilizer, a polymerized metal deactivator, a lubricant, a surfactant, and an antibacterial agent, if necessary. Specific examples of the mold release agent and heat stabilizer include those described in International Publication No. WO 2011 / 010741.

[0087] Particularly preferred release agents include stearic acid monoglyceride, stearic acid triglyceride, pentaerythritol tetrastearate, and a mixture of stearic acid triglyceride and stearyl stearate. The amount of the ester in the release agent is preferably 90% by weight or more, more preferably 95% by weight or more, when the release agent is taken as 100% by weight. The amount of the release agent to be mixed with the thermoplastic resin is preferably in the range of 0.005 to 2.0 parts by weight, more preferably in the range of 0.01 to 0.6 parts by weight, and even more preferably in the range of 0.02 to 0.5 parts by weight, relative to 100 parts by weight of the thermoplastic resin.

[0088] Examples of the heat stabilizer include phosphorus-based heat stabilizers, sulfur-based heat stabilizers, and hindered phenol-based heat stabilizers.

[0089] Particularly preferred phosphorus-based heat stabilizers include tris(2,4-di-tert-butylphenyl)phosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, and tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphonite. The content of the phosphorus-based heat stabilizer in the polycarbonate resin is preferably 0.001 to 0.2 parts by weight per 100 parts by weight of the thermoplastic resin.

[0090] A particularly preferred sulfur-based heat stabilizer is pentaerythritol-tetrakis(3-laurylthiopropionate). The content of the sulfur-based heat stabilizer in the thermoplastic resin is preferably 0.001 to 0.2 parts by weight based on 100 parts by weight of the thermoplastic resin.

[0091] Moreover, preferred hindered phenol-based heat stabilizers include octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0092] The content of the hindered phenol-based heat stabilizer in the thermoplastic resin is preferably 0.001 to 0.3 parts by weight based on 100 parts by weight of the thermoplastic resin.

[0093] The phosphorus-based heat stabilizer and the hindered phenol-based heat stabilizer can be used in combination.

[0094] The ultraviolet absorber is preferably at least one type of ultraviolet absorber selected from the group consisting of benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, triazine-based ultraviolet absorbers, cyclic iminoester-based ultraviolet absorbers, and cyanoacrylate-based ultraviolet absorbers.

[0095] Of the benzotriazole-based ultraviolet absorbents, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole and 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol] are more preferred.

[0096] Benzophenone-based ultraviolet absorbers include 2-hydroxy-4-n-dodecyloxybenzophenone and 2-hydroxy-4-methoxy-2'-carboxybenzophenone.

[0097] Examples of triazine-based ultraviolet absorbers include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol and 2-(4,6-bis(2.4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-[(octyl)oxy]-phenol.

[0098] As the cyclic imino ester type ultraviolet absorbent, 2,2'-p-phenylenebis(3,1-benzoxazin-4-one) is particularly suitable.

[0099] Examples of cyanoacrylate ultraviolet absorbers include 1,3-bis-[(2'-cyano-3',3'-diphenylacryloyl)oxy]-2,2-bis[(2-cyano-3,3-diphenylacryloyl)oxy]methyl)propane and 1,3-bis-[(2-cyano-3,3-diphenylacryloyl)oxy]benzene.

[0100] The amount of the ultraviolet absorber to be blended is preferably 0.01 to 3.0 parts by weight per 100 parts by weight of the thermoplastic resin. Within this range of blending amount, it is possible to impart sufficient weather resistance to the molded product of the thermoplastic resin depending on the application.

[0101] Antioxidants include triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenyl)propionate. butyl-4-hydroxybenzyl)benzene, N,N-hexamethylenebis(3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate and 3,9-bis{1,1-dimethyl-2-[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane. The amount of the antioxidant is preferably 0.50 parts by mass or less, more preferably 0.05 to 0.40 parts by mass, even more preferably 0.05 to 0.20 parts by mass or 0.10 to 0.40 parts by mass, and particularly preferably 0.20 to 0.40 parts by mass, relative to 100 parts by mass of the thermoplastic resin composition.

[0102] <Optical components> The optical member of the present invention contains the above-mentioned thermoplastic resin. Such an optical member is not particularly limited as long as it has an optical application in which the above-mentioned thermoplastic resin is useful, and examples of such an optical member include an optical disk, a transparent conductive substrate, an optical card, a sheet, a film, an optical fiber, a lens, a prism, an optical film, a base, an optical filter, and a hard coat film.

[0103] The optical member of the present invention may be composed of a resin composition containing the above-mentioned thermoplastic resin, and the resin composition may contain additives such as a heat stabilizer, a plasticizer, a light stabilizer, a polymerized metal deactivator, a flame retardant, a lubricant, an antistatic agent, a surfactant, an antibacterial agent, an ultraviolet absorber, a release agent, a bluing agent, a filler, and an antioxidant, as necessary.

[0104] <Optical lenses> The optical member of the present invention may in particular be an optical lens. Examples of such an optical lens include imaging lenses for mobile phones, smartphones, tablet terminals, personal computers, digital cameras, video cameras, vehicle-mounted cameras, surveillance cameras, and the like, and sensing cameras such as TOF cameras.

[0105] When the optical lens of the present invention is manufactured by injection molding, it is preferable to mold the lens under the conditions of a cylinder temperature of 230 to 350°C and a mold temperature of 70 to 180°C. More preferably, it is preferable to mold the lens under the conditions of a cylinder temperature of 250 to 300°C and a mold temperature of 80 to 170°C. If the cylinder temperature is higher than 350°C, the thermoplastic resin decomposes and discolors, and if it is lower than 230°C, the melt viscosity is high and molding is likely to be difficult. If the mold temperature is higher than 180°C, it is likely to be difficult to remove the molded piece made of the thermoplastic resin from the mold. On the other hand, if the mold temperature is lower than 70°C, the resin hardens too quickly in the mold during molding, making it difficult to control the shape of the molded piece, or it is likely to be difficult to sufficiently transfer the shape of the molded piece.

[0106] The optical lens of the present invention is preferably implemented as an aspherical lens as 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, and it is possible to reduce weight and molding costs. Therefore, aspherical lenses are particularly useful as camera lenses among optical lenses.

[0107] In addition, since the thermoplastic resin 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. Specific lens sizes are a thickness of 0.05 to 3.0 mm at the center, more preferably 0.05 to 2.0 mm, and even more preferably 0.1 to 2.0 mm. Also, a diameter of 1.0 mm to 20.0 mm, more preferably 1.0 to 10.0 mm, and even more preferably 3.0 to 10.0 mm. Also, the shape is preferably a meniscus lens with one side convex and the other side concave.

[0108] The lens made of the thermoplastic resin of the present invention can be formed by any method such as metal molding, cutting, polishing, laser processing, electric discharge processing, etching, etc. Among these, metal molding is more preferable in terms of production costs.

[0109] The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. EXAMPLES

[0110] The evaluation was carried out by the following method. <Thermoplastic resin composition> JEOL JNM-ECZ400S 1 The copolymerization ratio of each thermoplastic resin was calculated by measuring 1 H NMR.

[0111] <Refractive index> A 3 mm thick test piece of each thermoplastic resin was prepared and polished, and then the refractive index nd (587.56 nm) was measured using a Kalnew precision refractometer KPR-2000 manufactured by Shimadzu Corporation.

[0112] <Abbe number> The Abbe number (νd) was calculated from the refractive indexes at a temperature of 20° C. and wavelengths of 486.13 nm, 587.56 nm, and 656.27 nm using the following formula. νd=(nd-1) / (nF-nC) nd: refractive index at a wavelength of 587.56 nm, nF: refractive index at a wavelength of 486.13 nm, nC: refers to the refractive index at a wavelength of 656.27 nm.

[0113] <Absolute value of orientation birefringence> The thermoplastic resin was dissolved in methylene chloride, cast on a glass petri dish, and thoroughly dried to prepare a cast film having a thickness of 100 μm. The film was stretched twice at Tg+10° C., and the retardation (Re) at 589 nm was measured using an Ellipsometer M-220 manufactured by JASCO Corporation. The absolute value of the orientation birefringence (|Δn|) was calculated by the following formula. |Δn|=|Re / d| Δn: Orientation birefringence Re: Phase difference (nm) d: thickness (nm)

[0114] <Glass transition temperature (Tg)> The thermoplastic resin obtained was measured at a heating rate of 20°C / min using a Discovery DSC 25Auto model manufactured by TA Instruments Japan Co., Ltd. The sample was 5 to 10 mg.

[0115] <Example 1> The mixture consisted of 197.33 g (0.45 mol) of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (hereinafter sometimes abbreviated as BPEF), 7.61 g (0.03 mol) of 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane (hereinafter sometimes abbreviated as SPG), 7.76 g (0.03 mol) of 4,4'-(3,3,5-trimethylcyclohexyl Bisphenol A (hereinafter sometimes abbreviated as BisTMC), 109.25g (0.51mol) of diphenyl carbonate, and 62.5μL of sodium bicarbonate aqueous solution (2.5μmol of sodium bicarbonate) with a concentration of 40mmol / L and 54.7μL of tetramethylammonium hydroxide aqueous solution (15μmol of tetramethylammonium hydroxide) with a concentration of 274mmol / L as catalysts were heated to 180℃ under a nitrogen atmosphere and melted. After that, the reduced pressure was adjusted to 20kPa over 10 minutes. The temperature was raised to 250℃ at a rate of 60℃ / hr, and after the outflow amount of phenol became 70%, the pressure inside the reactor was reduced to 133Pa or less over 1 hour. The mixture was stirred for a total of 3.5 hours, and the resin was taken out after the reaction was completed. The copolymerization ratio of the obtained polycarbonate resin was 1 The refractive index, Abbe number, absolute value of orientation birefringence, and Tg of the polycarbonate resin were measured by H NMR.

[0116] <Examples 2 to 5> A polycarbonate resin was produced in the same manner as in Example 1, except that the monomer ratio was changed so that the copolymerization ratio of BPEF, SPG, and BisTMC was the ratio shown in Table 1.

[0117] <Comparative Examples 1 to 4> A polycarbonate resin was produced in the same manner as in Example 1, except that the monomer ratio was changed so that the copolymerization ratio of BPEF, SPG, and BisTMC was the ratio shown in Table 1.

[0118] <Result> The configurations and evaluation results of each of the examples and comparative examples are summarized in Table 1 below.

[0119] [Table 1]

[0120] BPEF: 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene SPG: 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane BisTMC: 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol

[0121] Examples 1 to 5 can satisfy all of the requirements for refractive index of about 1.600 to 1.660, Abbe number, low birefringence, and heat resistance.

[0122] In both Comparative Examples 1 and 2, polycarbonate resins consisting of BPEF, SPG and BisTMC are exemplified, but since the proportion of BPEF is small, the refractive index and birefringence are insufficient compared to the Examples.

[0123] In addition, in Comparative Example 3, a polycarbonate resin composed of BPEF and BisTMC is exemplified, but since it does not contain SPG, the Tg is higher than in the Examples, and it is not suitable for use as a molding material.

[0124] In Comparative Example 4, a polycarbonate resin made of BPEF and SPG is exemplified, but since it does not contain BisTMC, the Tg is lower than in the Examples, and the heat resistance is insufficient. [Industrial Applicability]

[0125] The thermoplastic resin of the present invention is used for optical materials and can be used for optical members such as optical lenses, prisms, optical disks, transparent conductive substrates, optical cards, sheets, films, optical fibers, optical films, optical filters, and hard coat films, and is particularly useful for optical lenses.

Claims

1. A thermoplastic resin containing repeating units represented by formula (1), formula (2) and formula (3), in which the repeating units represented by formula (1) account for 60 mol % or more and the refractive index is more than 1.600 and 1.660 or less. 【Chemistry 1】 (In formula (1), R １ ~R ４ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. 【Chemistry 2】 【Chemistry 3】 (In formula (3), n is in the range of 1 to 8, and R ５ and R ６ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms; R ７ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

2. The thermoplastic resin according to claim 1, wherein the repeating unit of the formula (1) is 60 mol % or more and 80 mol % or less.

3. R in the above formula (1) １ ~R ４ The thermoplastic resin according to claim 1 or 2, wherein is a hydrogen atom.

4. 3. The thermoplastic resin according to claim 1, wherein the repeating unit of formula (3) is a repeating unit derived from 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol.

5. The thermoplastic resin according to claim 1 or 2, having a glass transition temperature of 130 to 160°C.

6. The absolute value of orientation birefringence is 3.0×10 －３ The thermoplastic resin according to claim 1 or 2, wherein:

7. The absolute value of orientation birefringence is 1.0×10 －３ The thermoplastic resin according to claim 1 or 2, wherein:

8. The thermoplastic resin according to claim 1 or 2, having an Abbe number of 24.0 to 29.

0.

9. An optical member comprising the thermoplastic resin according to claim 1 or 2.

10. The optical member according to claim 9, which is an optical lens.

Images