Thermoplastic resin and optical member containing same

Abstract

An object of the present invention is to provide a thermoplastic resin for optical lenses that has a low refractive index, a low Abbe number, and a water absorption rate comparable to that of polycarbonate resin, so that optical lens designers can employ various types of lenses. The thermoplastic resin of the present invention contains (1) a unit represented by the following formula (1), (2) a carbonate unit derived from a spiroglycol, and (3) a carbonate unit derived from bisphenol Z or a derivative thereof, and has a refractive index of 1.510 to 1.570: JPEG2026035732000008.jpg40100 {In formula (1), R1, R2, R3, and R4 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms.}

Description

[Technical Field]

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

[0002] Optical glass or optical transparent resins are used as materials for optical elements used in optical systems of various cameras, such as cameras, film-integrated cameras, and video cameras, as well as sensing cameras. Optical glass has excellent heat resistance, transparency, dimensional stability, chemical resistance, and the like, and there are many types of materials with various refractive indices and Abbe numbers. However, optical glass has problems such as high material costs, poor moldability, and low productivity. In particular, processing it into aspherical lenses used for aberration correction requires extremely advanced technology and high costs, which poses a major obstacle to practical use.

[0003] On the other hand, optical lenses made of optical transparent resins, especially thermoplastic transparent resins, have the advantage that they can be mass-produced by injection molding and that aspherical lenses can be easily manufactured, and are currently used for camera lenses. Examples of such resins include polycarbonate made from bisphenol A, polystyrene, poly-4-methylpentene, polymethyl methacrylate, and amorphous polyolefins.

[0004] However, when optical transparent resins are used as optical lenses, in addition to refractive index and Abbe number, transparency, heat resistance, and low birefringence are required, so the areas 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 their areas of use are limited.

[0005] In the optical design of optical lenses, a method for correcting aberrations and chromatic aberrations by combining multiple lenses with different refractive indices and Abbe numbers is known. For example, a lens made of cycloolefin resin, which has a relatively low refractive index and a high Abbe number, is combined with a lens made of polycarbonate resin, which is made from bisphenol A and has a high refractive index and a low Abbe number, to correct aberrations and chromatic aberrations. However, the difference in water absorption between cycloolefin resin and polycarbonate resin results in a difference in the coefficient of expansion upon water absorption. When these two lenses are combined to form a lens unit, the lens size will differ when the lens absorbs water in the environment in which it is used, such as in a smartphone, and lens performance will be impaired.

[0006] Patent Document 1 reports a polycarbonate resin with a low refractive index and a high Abbe number that uses decahydro-1,4:5,8-dimethanonaphthalenediol (D-NDM), which exhibits water absorption at the same level as polycarbonate resins with a high refractive index and a low Abbe number. By combining these, the loss of lens performance due to differences in the coefficient of water absorption and expansion is mitigated. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2017 / 175693 Summary of the Invention [Problem to be solved by the invention]

[0008] In recent years, with the expansion of applications for optical units, the demands for optical performance have increased, and the design concepts of designers have expanded. Accordingly, the optical design of optical lenses is not limited to the combination of a resin lens with a relatively high refractive index and low Abbe number and a resin lens with a low refractive index and high Abbe number, as described above, but also requires combinations with resin lenses with a low refractive index and a low Abbe number.

[0009] Furthermore, designers will not adopt a resin unless it is suitable for use in optical lenses, not only in terms of refractive index and Abbe number, but also in terms of heat resistance, birefringence, and a small difference in coefficient of expansion due to water absorption from the above-mentioned resins.

[0010] Therefore, an object of the present invention is to provide a thermoplastic resin for optical lenses that has a low refractive index, a low Abbe number, and a water absorption rate comparable to that of polycarbonate resin, so that optical lens designers can employ various types of lenses. [Means for solving the problem]

[0011] The present inventors have found that the above problems can be solved by the present invention having the following aspects.

[0012] <<Aspect 1>> A thermoplastic resin containing repeating units represented by formula (1), formula (2), and formula (3) and having a refractive index of 1.510 to 1.570:

[0013] [ka]

[0014] {In formula (1), R1, R2, R3, and R4 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms.}

[0015] [ka]

[0016] [ka]

[0017] {In formula (3), n is a number ranging from 1 to 8, each R is independently selected from a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R5 and R6 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms}.

[0018] <<Aspect 2>> A thermoplastic resin according to aspect 1, having an Abbe number of 32.0 to 40.0.

[0019] Aspect 3 3. The thermoplastic resin according to any one of aspects 1 and 2, having a saturated water absorption of 0.1% to 0.7%.

[0020] Aspect 4 A thermoplastic resin according to any one of aspects 1 to 3, having a glass transition temperature of 130°C to 160°C.

[0021] Aspect 5 Orientation birefringence is 6×10 -3 A thermoplastic resin according to any one of aspects 1 to 4, wherein:

[0022] Aspect 6 A thermoplastic resin according to any one of aspects 1 to 5, wherein the repeating unit of the above formula (1) is from 1 mol % to 40 mol %.

[0023] Aspect 7 The thermoplastic resin according to any one of aspects 1 to 6, wherein the repeating unit of the formula (2) is 30 mol % or more and 60 mol % or less.

[0024] Aspect 8 A thermoplastic resin according to any one of aspects 1 to 7, wherein the repeating unit of the formula (3) is 20 mol % or more and 50 mol % or less.

[0025] Aspect 9 An optical member comprising the thermoplastic resin according to any one of the first to eighth embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, the embodiments for carrying out the present invention will be described in detail, but the present invention is not limited to these, and various modifications are possible within the scope of the gist of the present invention.

[0027] 《Thermoplastic resin》 The thermoplastic resin of the present invention contains repeating units represented by the above formula (1), formula (2) and formula (3), and has a refractive index of 1.510 to 1.570.

[0028] The repeating unit structure containing a polycyclic skeleton such as D-NDM described in Prior Art Document 1 has a high atomic density per unit volume, and is characterized by a high refractive index and a high Abbe number. On the other hand, the repeating unit structure containing the spiro ring structure of formula (2) and the cyclohexylidene bisphenol skeleton of formula (3) of the present invention reduces the atomic density per unit volume, resulting in a low refractive index and a low Abbe number. Furthermore, formulas (2) and (3) have positive birefringence, while formula (1), which has a cardo structure, has negative birefringence. Therefore, by combining these, it is possible to achieve a low refractive index, a low Abbe number, and a low orientational birefringence.

[0029] 《Thermoplastic resin structure》 In the above formula (1), R1, R2, R3, and R4 each independently represent 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.

[0030] 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.

[0031] 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.

[0032] Examples of the aryl group include a phenyl group, a tolyl group, a naphthyl group, and a xylyl group, with a phenyl group being preferred.

[0033] R1 to R4 are each independently preferably a hydrogen atom, a methyl group, or a phenyl group, more preferably a hydrogen atom or a phenyl group, and R1 and R2 are each independently preferably a hydrogen atom or a phenyl group, and further preferably R3 and R4 are each independently preferably a hydrogen atom.

[0034] The above formulas (2) and (3) have positive birefringence, whereas the above formula (1) having a cardo structure has negative birefringence. In the above case, the amount of the above formula (1) introduced can be increased without significantly increasing the refractive index, so that a low refractive index and low orientation birefringence are possible.

[0035] The repeating unit represented by the above formula (1) is preferably a repeating unit derived from 9,9-bis(4-(hydroxyethoxy)phenyl)fluorene (hereinafter sometimes abbreviated as BPEF) or 9,9-bis(4-(hydroxyethoxy)-3-phenylphenyl)fluorene, and more preferably a repeating unit derived from 9,9-bis(4-(hydroxyethoxy)phenyl)fluorene.

[0036] The thermoplastic resin of the present invention may contain the repeating unit represented by the above formula (1) in an amount of 1 mol% or more, 5 mol% or more, 10 mol% or more, 12 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, or 30 mol% or more, or 40 mol% or less, 35 mol% or less, 30 mol% or less, 25 mol% or less, 20 mol% or less, 15 mol% or less, or 10 mol% or less. The thermoplastic resin of the present invention may contain the repeating unit represented by the above formula (1) in an amount of preferably 1 mol% to 40 mol%, more preferably 5 mol% to 35 mol%, even more preferably 10 mol% to 35 mol%, particularly preferably 12 mol% to 35 mol%, and most preferably 15 mol% to 35 mol%.

[0037] By including the formula (1) in an amount equal to or less than the upper limit, it is possible to achieve a low refractive index, and by including the formula (1) in an amount equal to or more than the lower limit, it is possible to achieve low birefringence and high heat resistance.

[0038] 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 (hereinafter sometimes abbreviated as SPG).

[0039] The thermoplastic resin of the present invention may contain the repeating unit represented by the above formula (2) in an amount of 25 mol% or more, 30 mol% or more, 35 mol% or more, 40 mol% or more, 45 mol% or more, or 50 mol% or more, or 60 mol% or less, 55 mol% or less, 50 mol% or less, 45 mol% or less, or 40 mol% or less. The thermoplastic resin of the present invention may contain the repeating unit represented by the above formula (2) in an amount of preferably 25 mol% to 60 mol%, more preferably 30 mol% to 60 mol%, even more preferably 30 mol% to 55 mol%, and particularly preferably 30 mol% to 50 mol%.

[0040] By including the formula (2) in an amount equal to or less than the upper limit, high heat resistance can be achieved, and by including the formula (2) in an amount equal to or more than the lower limit, a low refractive index and a low Abbe number can be achieved.

[0041] In the 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. R each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, preferably a methyl group or an ethyl group, and more preferably a methyl group. R5 and R6 each independently represent 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.

[0042] 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.

[0043] 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.

[0044] Examples of the aryl group include a phenyl group, a tolyl group, a naphthyl group, and a xylyl group, with a phenyl group being preferred.

[0045] R5 and R6 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.

[0046] When the substituent R is as described above, it is possible to further improve heat resistance. In addition, when the substituents R5 and R6 are as described above, it is possible to increase the amount of the above formula (3) introduced without significantly increasing the refractive index, thereby enabling a low refractive index and high heat resistance.

[0047] The repeating unit represented by the above formula (3) is preferably a repeating unit derived from 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol (hereinafter sometimes abbreviated as BisTMC), 4,4'-cyclohexylidenebisphenol (hereinafter sometimes abbreviated as BisZ), or 4,4'-(3-methylcyclohexylidene)bisphenol (hereinafter sometimes abbreviated as Bis3MZ), and more preferably a repeating unit derived from BisTMC.

[0048] The thermoplastic resin of the present invention may contain the repeating unit represented by the above formula (3) in an amount of 20 mol% or more, 25 mol% or more, 30 mol% or more, 35 mol% or more, or 40 mol% or more, or 50 mol% or less, 45 mol% or less, 40 mol% or less, 35 mol% or less, or 30 mol% or less. The thermoplastic resin of the present invention may contain the repeating unit represented by the above formula (3) in an amount of preferably 20 mol% to 50 mol%, more preferably 25 mol% to 50 mol%, even more preferably 25 mol% to 45 mol%, and particularly preferably 30 mol% to 45 mol%.

[0049] By including the formula (3) in an amount equal to or less than the upper limit, it is possible to achieve low birefringence, and by including the formula (3) in an amount equal to or more than the lower limit, it is possible to achieve a low refractive index, a low Abbe number, and high heat resistance.

[0050] The thermoplastic resin of the present invention may contain repeating units other than those represented by the above formulas (1), (2), and (3), as long as the advantageous effects of the present invention are obtained. 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, norbornanedimethanol, 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 all repeating units.

[0051] The thermoplastic resin of the present invention preferably 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 a carbonic acid diester in excess of the dihydroxy compound used as the raw material during polymerization, for example, 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 = (amount of terminal phenolic hydroxyl groups / total amount of terminals) x 100 The total terminals consist of a terminal phenolic hydroxyl group, a terminal alcoholic hydroxyl group, and a terminal phenyl group.

[0052] Although not limited to this example, specifically, the terminal phenolic hydroxyl group ratio can be determined by the following method.

[0053] (1) The terminal phenolic hydroxyl group is observed by 1H NMR measurement of the thermoplastic resin, and the integral of the corresponding peak is taken and set as 1. At the same time, the integral intensity (A) of one proton of the fluorene structure is calculated from the integral intensity of the peaks at positions 4 and 5 of the fluorene structure derived from the above formula (1). Naturally, when no peak of the terminal phenolic hydroxyl group is observed, the ratio of the terminal phenolic hydroxyl group is 0.

[0054] (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 integrated intensity (B) in the terminal 1H NMR spectrum is calculated using the following formula from the mol% and integrated intensity (A) in the above formula (1). (B) = (A) × 100 × 2 / ([mol% of the above formula (1)] × average degree of polymerization)

[0055] (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.

[0056] 《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 589 nm, is 1.510 or more, or may be 1.515 or more, 1.520 or more, 1.525 or more, 1.530 or more, 1.535 or more, or 1.540 or more, and may be 1.570 or less, 1.565 or less, 1.560 or less, or 1.555 or less. For example, the refractive index of the thermoplastic resin of the present invention may be 1.510 to 1.570, 1.520 to 1.570, 1.520 to 1.560, or 1.530 to 1.560.

[0057] The Abbe number of the thermoplastic resin of the present invention may be 32.0 or more, 32.5 or more, 33.0 or more, 33.5 or more, or 34.0 or more, or 40.0 or less, 39.5 or less, 39.0 or less, 38.5 or less, 38.0 or less, 37.5 or less, or 37.0 or less. For example, the Abbe number of the thermoplastic resin of the present invention may be 32.0 to 40.0, 32.0 to 38.0, 32.0 to 37.0, or 32.0 to 36.0.

[0058] Here, the Abbe number is calculated using the following formula from the refractive indexes at a temperature of 20° C. and wavelengths of 486.13 nm, 587.56 nm, and 656.27 nm: 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: Refractive index at a wavelength of 656.27 nm.

[0059] The specific viscosity of the thermoplastic resin of the present invention is preferably in the range of 0.12 to 0.32, more preferably in the range of 0.18 to 0.30. When the specific viscosity is 0.12 to 0.32, an excellent balance between moldability and strength is achieved.

[0060] 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. Specific viscosity (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]

[0061] The absolute value of the orientation birefringence (Δn) of the thermoplastic resin of the present invention is 6.0×10 -3 Preferably, it is 5.5 x 10 or less. -3 More preferably, it is 5.0×10 or less. -3 More preferably, it is 4.5×10 or less. -3 It is preferable that:

[0062] If the orientation birefringence is below the above level, it does not have a significant effect on chromatic aberration, and the performance can be maintained as per the optical design. Orientation birefringence (Δn) 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.

[0063] The thermoplastic resin of the present invention preferably has a total light transmittance of 80% or more, more preferably 85% or more, and even more preferably 88% or more, at a thickness of 1 mm.

[0064] The saturated water absorption of the thermoplastic resin of the present invention may be 0.10% or more, 0.15% or more, 0.20% or more, 0.25% or more, or 0.30% or more, or 0.70% or less, 0.65% or less, or 0.60% or less. For example, 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%.

[0065] The glass transition temperature of the thermoplastic resin of the present invention may be 130° C. or higher, 135° C. or higher, 140° C. or higher, or 145° C. or higher, or may be 160° C. or lower, 155° C. or lower, or 150° C. or lower. The glass transition temperature of the thermoplastic resin of the present invention is preferably 130° C. to 160° C., more preferably 135° C. to 160° C., even more preferably 135° C. to 155° C., and particularly preferably 140° C. to 155° C.

[0066] Examples of the thermoplastic resin of the present invention include polycarbonates containing carbonate structures represented by formula (1), formula (2), and formula (3) in their repeating units, and polyester carbonates containing repeating units represented by formula (1), formula (2), and formula (3) and ester structures other than these in their repeating units. Among these, polycarbonates are preferred in terms of heat resistance and moist heat resistance.

[0067] <Method for producing polycarbonate resin> The polycarbonate resin of the present invention is produced by a reaction means known per se for producing ordinary polycarbonate resins, for example, a method of reacting a dihydroxy compound with a carbonate precursor such as a carbonic acid diester. The basic means for these production methods will now be briefly described.

[0068] The transesterification reaction using a carbonate diester as a carbonate precursor is carried out by stirring a predetermined ratio of dihydroxy component with a carbonate diester under heating in an inert gas atmosphere, and distilling off the resulting alcohol or phenol. The reaction temperature varies depending on the boiling point of the resulting alcohol or phenol, 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 resulting alcohol or phenol. If necessary, a terminal capping agent, antioxidant, etc. may also be added.

[0069] The carbonic acid diester used in the transesterification reaction includes esters 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. Of 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, per mol of the total amount of dihydroxy compounds.

[0070] 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.

[0071] 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.

[0072] Examples of alkali metal compounds 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 benzoate, potassium benzoate, cesium benzoate, lithium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium phenylphosphate, disodium salt, dipotassium salt, dicesium salt, dilithium salt of bisphenol A, sodium salt, potassium salt, cesium salt, and lithium salt of phenol.

[0073] Examples of alkaline earth metal compounds include magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, magnesium diacetate, calcium diacetate, strontium diacetate, and barium diacetate.

[0074] 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 nitrogen-containing compound include bases or basic salts, such as tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, and tetraphenylammonium tetraphenylborate.

[0075] 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. The catalysts used in WO 2011 / 010741 and JP 2017-179323 A may also be used.

[0076] Furthermore, a catalyst comprising aluminum or a compound thereof and a phosphorus compound may be used. In this case, the amount of the catalyst may be 8×10 mol or more, 9×10 mol or more, or 1×10 mol or more, or 1×10 mol or less, 8×10 mol or less, or 6×10 mol or less, per mol of the total of all monomer units used.

[0077] Examples of aluminum salts include organic and inorganic aluminum salts. Examples of organic aluminum 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 inorganic aluminum 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 diso-propoxide.

[0078] Examples of phosphorus compounds include phosphonic acid compounds, phosphinic acid compounds, phosphine oxide compounds, phosphonous acid compounds, phosphinous 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.

[0079] The amount of these polymerization catalysts used is preferably 0.1 μmol to 500 μmol, more preferably 0.5 μmol to 300 μmol, and even more preferably 1 μmol to 100 μmol, per 1 mol of the dihydroxy component.

[0080] A catalyst deactivator can also be added in the latter stage of the reaction. Known catalyst deactivators are effectively used as the catalyst deactivator, but among these, ammonium salts and phosphonium salts of sulfonic acid are preferred. Salts of dodecylbenzenesulfonic acid, such as tetrabutylphosphonium dodecylbenzenesulfonate, and salts of paratoluenesulfonic acid, such as tetrabutylammonium paratoluenesulfonate, are more preferred.

[0081] Preferred examples of sulfonic acid esters include methyl benzenesulfonate, ethyl benzenesulfonate, butyl benzenesulfonate, octyl benzenesulfonate, phenyl benzenesulfonate, methyl paratoluenesulfonate, ethyl paratoluenesulfonate, butyl paratoluenesulfonate, octyl paratoluenesulfonate, and phenyl paratoluenesulfonate. Of these, tetrabutylphosphonium dodecylbenzenesulfonate is most preferably used.

[0082] 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.

[0083] <Method for producing polyester carbonate resin> The thermoplastic resin of the present invention may be a polyester carbonate resin, which is produced by a reaction method known per se for producing ordinary polyester carbonate resins, 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.

[0084] The reaction of a dihydroxy compound, a dicarboxylic acid, or its acid chloride with phosgene is carried out in a non-aqueous system in the presence of an acid binder and a solvent. Examples of acid binders that can be used include pyridine, dimethylaminopyridine, and tertiary amines. Examples of solvents that can be used include halogenated hydrocarbons such as methylene chloride and chlorobenzene. It is desirable to use a molecular weight regulator such as a terminal terminator as phenol or p-tert-butylphenol. The reaction temperature is usually 0 to 40°C, and the reaction time is preferably several minutes to 5 hours.

[0085] 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, typically at 120 to 350°C, preferably 150 to 300°C. The degree of vacuum is gradually increased, and finally reduced to 133 Pa or less, to distill off the produced alcohols. The reaction time is typically about 1 to 4 hours. Furthermore, a polymerization catalyst can be used in the transesterification reaction to promote the reaction. Such a polymerization catalyst preferably uses an alkali metal compound, alkaline earth metal compound, or heavy metal compound as the main component, and optionally further uses a nitrogen-containing basic compound as a minor component.

[0086] Examples of alkali metal compounds include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium bicarbonate, potassium bicarbonate, lithium bicarbonate, sodium carbonate, potassium carbonate, lithium carbonate, sodium acetate, potassium acetate, lithium acetate, sodium stearate, potassium stearate, lithium stearate, the sodium salt, potassium salt, and lithium salt of bisphenol A, sodium benzoate, potassium benzoate, and lithium benzoate. Examples of alkaline earth metal compounds include calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, calcium bicarbonate, barium bicarbonate, magnesium bicarbonate, strontium bicarbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate, and strontium stearate.

[0087] Examples of the nitrogen-containing basic compound include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylamine, triethylamine, dimethylbenzylamine, triphenylamine, and dimethylaminopyridine.

[0088] As other transesterification catalysts, the catalysts exemplified as transesterification catalysts in the above-mentioned method for producing polycarbonate can be similarly used.

[0089] When the thermoplastic resin of the present invention is a polyester carbonate, the catalyst may be removed or deactivated after the polymerization reaction to maintain thermal stability and hydrolytic stability. Generally, a method of deactivating the catalyst by adding a known acidic substance is preferably carried out. Specific examples of such 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, phosphites 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 deactivators include phosphate esters such as octyl phosphate 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 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. These deactivators are used in an amount of 0.01 to 50 times, preferably 0.3 to 20 times, the amount of catalyst. Less than 0.01 times the amount of catalyst is undesirable because the deactivation effect is insufficient. More than 50 times the amount of catalyst is undesirable because the heat resistance decreases and the molded product is more likely to be discolored.

[0090] 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.

[0091] 《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, an antibacterial agent, etc. Specific examples of the mold release agent and heat stabilizer include those described in WO 2011 / 010741.

[0092] 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, based on 100% by weight of the release agent. The amount of the release agent to be blended with the thermoplastic resin is preferably in the range of 0.005 to 2.0 parts by weight, more preferably 0.01 to 0.6 parts by weight, and even more preferably 0.02 to 0.5 parts by weight, based on 100 parts by weight of the thermoplastic resin.

[0093] Examples of the heat stabilizer include phosphorus-based heat stabilizers, sulfur-based heat stabilizers, and hindered phenol-based heat stabilizers.

[0094] 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.

[0095] 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 per 100 parts by weight of the thermoplastic resin.

[0096] Further, 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].

[0097] The content of the hindered phenol-based heat stabilizer in the thermoplastic resin is preferably 0.001 to 0.3 parts by weight relative to 100 parts by weight of the thermoplastic resin.

[0098] The phosphorus-based heat stabilizer and the hindered phenol-based heat stabilizer can also be used in combination.

[0099] The ultraviolet absorber is preferably at least one 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.

[0100] Of the benzotriazole-based ultraviolet absorbers, 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.

[0101] Benzophenone-based ultraviolet absorbers include 2-hydroxy-4-n-dodecyloxybenzophenone and 2-hydroxy-4-methoxy-2'-carboxybenzophenone.

[0102] 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.

[0103] As the cyclic iminoester-based ultraviolet absorber, 2,2'-p-phenylenebis(3,1-benzoxazin-4-one) is particularly suitable.

[0104] 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.

[0105] The amount of ultraviolet absorber to be blended is preferably 0.01 to 3.0 parts by weight per 100 parts by weight of the thermoplastic resin, and within this range of blending amount, it is possible to impart sufficient weather resistance to the thermoplastic resin molded product depending on the application.

[0106] 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-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 to be blended 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, per 100 parts by mass of the thermoplastic resin composition.

[0107] 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 is used for optical applications in which the above-mentioned thermoplastic resin is useful, and examples thereof include optical disks, transparent conductive substrates, optical cards, sheets, films, optical fibers, lenses, prisms, optical films, substrates, optical filters, and hard coat films.

[0108] 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 needed.

[0109] Optical Lenses The optical member of the present invention can particularly include an optical lens, such as an imaging lens for a mobile phone, a smartphone, a tablet terminal, a personal computer, a digital camera, a video camera, an in-vehicle camera, a surveillance camera, or the like, or a sensing camera such as a TOF camera.

[0110] When the optical lens of the present invention is manufactured by injection molding, molding is preferably performed under conditions of a cylinder temperature of 230 to 350°C and a mold temperature of 70 to 180°C. More preferably, molding is performed under 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 will decompose and discolor, and if it is lower than 230°C, the melt viscosity will be high, making molding difficult. Furthermore, if the mold temperature is higher than 180°C, it will be difficult to remove a molded piece made of a thermoplastic resin from the mold. On the other hand, if the mold temperature is lower than 70°C, the resin will harden too quickly in the mold during molding, making it difficult to control the shape of the molded piece and making it difficult to sufficiently transfer the shape imprinted on the mold.

[0111] The optical lens of the present invention is preferably implemented as an aspherical lens, if necessary. Since a single aspherical lens can substantially eliminate spherical aberration, 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.

[0112] Furthermore, because 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 include 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. Furthermore, the diameter is 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. Furthermore, the shape of the lens is preferably a meniscus lens, with one side convex and the other concave.

[0113] The lens made of the thermoplastic resin of the present invention can be formed by any method such as mold molding, cutting, polishing, laser processing, electrical discharge processing, etching, etc. Among these, mold molding is more preferred in terms of production costs.

[0114] The present invention will be explained in more detail in the following examples, but the present invention is not limited thereto.

[0115] Evaluation Method <Thermoplastic resin composition> The composition ratio of each thermoplastic resin was calculated by measuring 1H NMR using a JEOL JNM-ECZ400S.

[0116] <Glass transition temperature> The thermoplastic resin obtained was measured at a heating rate of 20°C / min using a Discovery DSC25Auto model manufactured by TA Instruments Japan Co., Ltd. Samples weighing 5 to 10 mg were used.

[0117] <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.

[0118] <Abbe number> The Abbe number was calculated from the refractive indexes at 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: Refractive index at a wavelength of 656.27 nm.

[0119] <Absolute value of orientation birefringence> The thermoplastic resin was dissolved in methylene chloride, cast onto a glass dish, and thoroughly dried to prepare a 100 μm thick cast film. 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 orientation birefringence (|Δn|) was calculated using the following formula: |Δn|=|Re / d| Δn: Orientation birefringence Re: Phase difference (nm) d: thickness (nm)

[0120] <Water absorption rate> Plate-shaped molded pieces obtained by injection molding were measured in accordance with ISO62.

[0121] <Evaluation of lens optical distortion> An aspherical lens with a thickness of 0.2 mm, a convex curvature radius of 5 mm, a concave curvature radius of 4 mm, and a diameter of 5 mm was injection molded using an SE30DU injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., with a cylinder temperature of 270°C and a mold temperature of 115°C. The aspherical lens was sandwiched between two polarizing plates and optical distortion was evaluated by visually checking for light leakage using the crossed Nicols method. Evaluation was based on the following criteria. A: There is almost no light leakage. B: Slight light leakage is observed. C: There is light leakage. F: Light leakage is noticeable. [Example]

[0122] Example 1 21.93 g (0.05 mol) of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (BPEF), 173.50 g (0.57 mol) of 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5.5)undecane (SPG), 117.95 g (0.38 mol) of 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol (BisTMC), 218.50 g (1.02 mol) of diphenyl carbonate, and 0.125 mL of a 40 mmol / L aqueous solution of sodium bicarbonate (5.0 μmol of sodium bicarbonate) and 0.109 mL of a 274 mmol / L aqueous solution of tetramethylammonium hydroxide (30 μmol of tetramethylammonium hydroxide) were heated to 180 °C under a nitrogen atmosphere and melted. The degree of vacuum was then adjusted to 20 kPa over 10 minutes. The temperature was raised to 250°C at a rate of 60°C / hr, and once the amount of phenol effluent had reached 70%, the pressure inside the reactor was reduced to 133 Pa or less over 1 hour. The reaction was carried out with stirring for a total of 3.5 hours, and after completion of the reaction, the resin was removed from the flask. The composition ratio of the resulting polycarbonate resin was measured by NMR.

[0123] Examples 2 to 10 Polycarbonate resins were produced in the same manner as in Example 1, except that the monomer ratios were changed so that the composition ratios of BPEF, SPG, and BisTMC were as shown in Table 1.

[0124] "result" The configurations and evaluation results of each of the examples and comparative examples are summarized in Table 1 below.

[0125] [Table 1] [Industrial Applicability]

[0126] The thermoplastic resin of the present invention can be used in optical materials, 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

[Claim 1] A thermoplastic resin containing repeating units represented by formula (1), formula (2), and formula (3) and having a refractive index of 1.510 to 1.570: 【Chemistry 1】 {In formula (1), R １ , R ２ , R ３ and R ４ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. 【Chemistry 2】 【Transformation 3】 In formula (3), n is a number ranging from 1 to 8, and each R is independently selected from a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; ５ and R ６ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms.

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