JP2011037932A - Aromatic polycarbonate resin for optical material and composition comprising the same and used for light guide plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aromatic polycarbonate resin having high flowability. <P>SOLUTION: The aromatic polycarbonate resin for optical materials is obtained by carbonate-bonding at least one compound selected from compounds represented by formula (1) to at least one compound selected from compounds represented by formula (2) with phosgene or a carbonic acid diester, wherein the molar fraction of the compound represented by formula (2) is 1 to 90% based on the total amount of the bisphenols. In the formulas, X is a single bond, oxygen atom, sulfur atom, sulfone group, a 2 to 10C alkylidene group, a 5 to 12C cycloalkylidene group, a 7 to 15C arylalkylidene group, fluorenylidene group or α,α,α',α'-tetramethylxylidene group. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an aromatic polycarbonate resin, and more particularly to an aromatic polycarbonate resin having high fluidity, impact resistance, transferability, heat resistance, thermal stability, and moldability. This aromatic polycarbonate resin can be suitably used as a material for plastic optical products such as a light guide plate for liquid crystal, an optical disk substrate, various lenses, a prism, and an optical fiber.

  A conventional aromatic polycarbonate resin obtained by reacting 2,2-bis (4-hydroxyphenyl) propane (commonly referred to as bisphenol A, hereinafter abbreviated as BPA) with phosgene or a carbonic acid diester is excellent in heat resistance and transparency, and Since it has excellent mechanical properties such as impact resistance, it is widely used as a structural material as well as a light guide plate for liquid crystal, an optical disk substrate, various lenses, a prism, an optical fiber and the like as an optical material.

  Usually, an aromatic polycarbonate resin is molded by heating and melting. However, since a conventional aromatic polycarbonate resin is a low fluidity material, a thin and large material cannot be molded. Therefore, when molding an optical material made of a conventional aromatic polycarbonate resin, a method of molding at a high temperature using a resin having a relatively low molecular weight in order to improve fluidity is performed. However, the conventional aromatic polycarbonate resin has a problem that the improvement in fluidity is limited even if the above-described means is used, and the impact resistance is lowered due to the reduction in molecular weight. With the spread of optical material applications in recent years, there is a strong demand for the development of higher fluidity materials in some optical material fields.

  As a technique for improving the fluidity, a method for reducing the molecular weight is known, and is partially put into practical use for a light guide plate or an optical disk, but by reducing the molecular weight, the impact resistance is also reduced, and the When the size was increased, only materials with low practical value were obtained.

  A branched polycarbonate resin characterized by using a trifunctional or higher polyfunctional organic compound having a phenolic hydroxyl group as a branching agent as a resin material excellent in fluidity and impact resistance (Patent Document 1), tert- An aromatic polycarbonate resin (Patent Document 2) having an octylphenoxy group as a terminal group is known. Moreover, an aromatic polycarbonate resin having a long-chain alkylphenoxy group as a terminal group (Patent Document 3), a polycarbonate resin composition (Patent Document 4) composed of a copolyestercarbonate having an aliphatic segment and an aromatic polycarbonate has been proposed. .

  However, even with the resin material in the above proposal, sufficient fluidity cannot be secured for producing a desired molded product, and in addition, in either proposal, only a molded product having low impact value and low practical value is obtained. I couldn't.

Japanese Patent Laid-Open No. 60-215019 JP 2001-208917 A JP 2001-208918 A JP 2001-215336 A

  The present invention seeks to solve the problems associated with the prior art as described above, and has higher fluidity than conventional aromatic polycarbonate resins and has impact resistance that can withstand practical use. It is an object to provide an aromatic polycarbonate resin.

As a result of intensive studies, the present inventors have determined that at least one selected from the compound represented by the general formula (1) and at least one selected from the compound represented by the general formula (2) are phosgene or It has been found that an aromatic polycarbonate resin for an optical material, which is carbonate-bonded with a carbonic acid diester and has a molar fraction of the compound represented by the general formula (2) with respect to all bisphenols of 1 to 90%, can solve the above problems. The present invention has been reached.


(In the formula, X is a single bond, an oxygen atom, a sulfur atom, a sulfone group, an alkylidene group having 2 to 10 carbon atoms, a cycloalkylidene group having 5 to 12 carbon atoms, an arylalkylidene group having 7 to 15 carbon atoms, or a fluorenylidene group. Or α, α, α ′, α′-tetramethylxylidene group.)


A preferred embodiment of the present invention is an aromatic polycarbonate resin for an optical material, wherein the aromatic polycarbonate has a viscosity average molecular weight (Mv) of 15,000 to 40,000.
Another preferred embodiment of the present invention is an aromatic polycarbonate resin for optical materials in which the molar fraction of 4,4′-methylenebisphenol in the compound represented by the general formula (2) is 99% or more.
Another preferred embodiment of the present invention is an aromatic polycarbonate resin for optical materials in which the compound represented by the general formula (1) is 2,2-bis (4-hydroxyphenyl) propane.
Another preferred embodiment of the present invention is an aromatic polycarbonate resin for an optical material having an Izod impact value of 250 J / m or more indicating impact resistance.
Another preferred embodiment of the present invention is an aromatic polycarbonate resin for optical materials having a Q value indicating fluidity of 35 × 10 ⁻² cc / s or more.
Another embodiment of the present invention is a composition for a light guide plate containing the above aromatic polycarbonate resin for optical materials.
Furthermore, another embodiment of the present invention is a molded article containing the above aromatic polycarbonate resin for optical materials.

  The aromatic polycarbonate resin of the present invention is superior in fluidity and impact resistance compared to conventional aromatic polycarbonate resins, and has characteristics required for optical materials such as light guide plates for liquid crystals and optical disk substrates (for example, transferability, heat resistance). Can be used as a thin-walled and large-sized optical material.

  Hereinafter, the present invention will be described in detail. The aromatic polycarbonate resin of the present invention is a thermoplastic aromatic polycarbonate copolymer obtained by reacting two or more kinds of aromatic dihydroxy compounds with phosgene or a carbonic acid diester.

  As a manufacturing method of aromatic polycarbonate resin, a well-known method, for example, a phosgene method (interfacial polymerization method), a melting method (transesterification method), etc. are mentioned.

  Examples of the compound represented by the general formula (1) used as a raw material include 2,2-bis (4-hydroxyphenyl) propane (BPA), 1,1-bis (4-hydroxyphenyl) ethane, 2,2 -Bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3, 3,5-triethylcyclohexane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl)- 4-methylpentane, bis (4-hydroxyphenyl) phenylmethane, 4,4'-biphenol, bis (4-hydroxyphenyl) sulfur Down, 4,4'-thio-biphenol, and the like. Among these, bis (4-hydroxyphenyl) alkane is preferable, and BPA is particularly preferable from the viewpoint of impact resistance.

  The compound represented by the general formula (2) used as a raw material is generally called bisphenol F (hereinafter abbreviated as BPF), and BPF is 4,4′-methylenebisphenol (hereinafter referred to as p, p-BPF). Abbreviation), 2,4′-methylenebisphenol (hereinafter abbreviated as o, p-BPF), 2,2′-methylenebisphenol (hereinafter abbreviated as o, o-BPF) alone or a mixture thereof. In the present invention, each bisphenol F may be used alone or a mixture may be used. Among these, p, p-BPF is preferable from the viewpoint of impact resistance, reactivity, and ease of molecular weight adjustment. In particular, the molar fraction of p, p-BPF in the compound represented by the general formula (2) is preferably 99% or more.

  In the present invention, the molar fraction of the compound represented by the general formula (2) with respect to the total bisphenol is 1 to 90%, and if it exceeds 90%, insoluble matter is precipitated during polymerization, and a polycarbonate resin cannot be obtained. is there. The molar fraction is particularly preferably 20 to 80% from the balance of reactivity, impact resistance and fluidity.

  The reaction by the interfacial polymerization method uses two or more kinds of aromatic dihydroxy compounds, and if necessary, a molecular weight adjusting agent (terminal stopper) and an antioxidant for antioxidants of the aromatic dihydroxy compounds, and To be done. That is, in the presence of an organic solvent inert to the reaction and an alkaline aqueous solution, the pH is usually kept at 9 or more, phosgene is reacted, and then a polymerization catalyst such as a tertiary amine or a quaternary ammonium salt is added to the interface. Polymerization is performed to obtain a polycarbonate resin. The reaction temperature is preferably 0 to 40 ° C., and the reaction time is preferably 10 minutes to 6 hours.

  Here, examples of the organic solvent inert to the reaction include chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, chloroform, monochlorobenzene and dichlorobenzene, and aromatic hydrocarbons such as benzene, toluene and xylene. . Moreover, as an alkali compound used for alkaline aqueous solution, hydroxide of alkali metals, such as sodium hydroxide and potassium hydroxide, is mentioned.

  Examples of the molecular weight regulator include compounds having a monovalent phenolic hydroxyl group, and specific examples thereof include m-methylphenol, p-methylphenol, m-propylphenol, p-propylphenol, p-tert-butylphenol. (Hereinafter abbreviated as PTBP), p-long chain alkyl-substituted phenol, and the like. The usage-amount of a molecular weight modifier is 1-20 mol normally with respect to 100 mol of aromatic compounds, Preferably it is 2-10 mol.

  As a melt transesterification method, for example, it is carried out as a transesterification reaction in the presence of a basic catalyst between a carbonic acid diester and two or more aromatic dihydroxy compounds.

  Examples of the carbonic acid diester include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate, and dicyclohexyl carbonate. Of these, diphenyl carbonate is particularly preferred. The carbonic acid diester is preferably used in a ratio of 0.97 to 1.20 mol, more preferably 0.99 to 1.10 mol, relative to a total of 1 mol of the dihydroxy compound.

  Examples of the basic compound catalyst include alkali metal compounds and / or alkaline earth metal compounds and nitrogen-containing compounds.

  Examples of such compounds include organic acid salts such as alkali metal and alkaline earth metal compounds, inorganic acid salts, oxides, hydroxides, hydrides or alkoxides, quaternary ammonium hydroxides and salts thereof, and amines. Etc. are preferably used, and these compounds can be used alone or in combination.

  Specific examples of the alkali metal compound include sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide, sodium bicarbonate, potassium bicarbonate, cesium bicarbonate, lithium bicarbonate, sodium carbonate, potassium carbonate, carbonate Cesium, lithium carbonate, sodium acetate, potassium acetate, cesium acetate, lithium acetate, sodium stearate, potassium stearate, cesium stearate, lithium stearate, sodium borohydride, sodium borohydride, sodium benzoate, potassium benzoate Cesium benzoate, lithium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium phenyl phosphate, disodium salt of bisphenol A, 2 potassium salt, 2 cesium , 2 lithium salt, sodium salt of phenol, potassium salt, cesium salt, lithium salt or the like is used.

  Specific examples of the alkaline earth metal compound include magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium hydrogen carbonate, calcium hydrogen carbonate, strontium hydrogen carbonate, barium hydrogen carbonate, magnesium carbonate, calcium carbonate. Strontium carbonate, barium carbonate, magnesium acetate, calcium acetate, strontium acetate, barium acetate, magnesium stearate, calcium stearate, calcium benzoate, magnesium phenyl phosphate, and the like are used.

  Specific examples of the nitrogen-containing compound include quaternary compounds having an alkyl or aryl group such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and trimethylbenzylammonium hydroxide. Ammonium hydroxides; secondary amines such as triethylamine and dimethylamine; primary amines such as propylamine and butylamine; imidazoles such as 2-methylimidazole, 2-phenylimidazole and benzimidazole; or ammonia and tetramethylammonium Borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, tetraphenylammonium tetraf Base or basic salt such as Niruboreto are used.

These catalysts are used in a ratio of 10 ⁻⁹ to 10 ⁻³ mol, preferably 10 ⁻⁷ to 10 ⁻⁵ , relative to a total of 1 mol of the dihydroxy compound.

  The transesterification reaction according to the present invention can be carried out by a known melt polycondensation method. That is, melt polycondensation is carried out using the above-mentioned raw materials and catalyst while removing by-products by a transesterification reaction under heating at normal pressure or under reduced pressure. The reaction is generally carried out in a multistage process of two or more stages.

  Specifically, the reaction at the first stage is allowed to react at a temperature of 120 to 260 ° C., preferably 180 to 240 ° C. for 0.1 to 5 hours, preferably 0.5 to 3 hours. Next, the reaction temperature is raised while raising the degree of vacuum of the reaction system to react the dihydroxy compound and the carbonic acid diester. Finally, the reaction is carried out at a temperature of 200 to 350 ° C. for 0.3 to 10 hours under a reduced pressure of 1 mmHg or less. Perform a condensation reaction. Such a reaction may be carried out continuously or batchwise. The reaction apparatus used for carrying out the above reaction is equipped with paddle blades, lattice blades, glasses blades, etc. even with vertical types equipped with vertical stirring blades, Max blend stirring blades, helical ribbon stirring blades, etc. It may be a horizontal type or an extruder type equipped with a screw, and it is preferable to use a reaction apparatus in which these are appropriately combined in consideration of the viscosity of the polymer.

  After completion of the polymerization reaction, the aromatic polycarbonate resin of the present invention removes or deactivates the catalyst in order to maintain thermal stability and hydrolysis stability. In general, a method of deactivating a catalyst by adding a known acidic substance is preferably performed. Specific examples of these substances include aromatic sulfonic acids such as p-toluenesulfonic acid, aromatic sulfonic acid esters such as p-toluenesulfonic acid butyl and p-toluenesulfonic acid hexyl, and p-toluenesulfonic acid. Aromatic sulfonates such as tetrabutylphosphonium salts, organic halides such as stearic acid chloride, benzoyl chloride and p-toluenesulfonic acid chloride, alkyl sulfuric acids such as dimethyl sulfate, and organic halides such as benzyl chloride are preferably used. It is done.

  After deactivation of the catalyst, a step of devolatilizing and removing low-boiling compounds in the polymer at a pressure of 0.1 to 1 mmHg and a temperature of 200 to 350 ° C. may be provided. For this purpose, paddle blades, lattice blades, glasses A horizontal apparatus provided with a stirring blade having excellent surface renewability such as a blade or a thin film evaporator is preferably used.

  The aromatic polycarbonate resin of the present invention preferably has a viscosity average molecular weight (Mv) of 15,000 to 40,000. More preferably, the viscosity average molecular weight (Mv) is 16,000 to 25,000. When the viscosity average molecular weight (Mv) is less than 15,000, the mechanical strength is lowered, and when it exceeds 40,000, the melt viscosity is increased, the fluidity is lowered, and molding of a thin-walled / large-sized optical material is possible. It becomes difficult.

The aromatic polycarbonate resin of the present invention preferably has an Izod impact value of impact resistance of 250 J / m or more, more preferably 400 J / m or more. In addition, the aromatic polycarbonate resin of the present invention preferably has a Q value indicating fluidity of 35 × 10 ⁻² cc / s or more, and more preferably 50 × 10 ⁻² cc / s or more. When the Izod impact value is less than 250 J / m, the strength is insufficient and lacks practicality, and when the Q value is less than 35 × 10 ⁻² cc / s, the fluidity is insufficient and it becomes difficult to form a thin-walled / large-sized molded product.

  Moreover, the composition for light-guide plates of this invention may mix | blend various additives in the range which does not impair the objective of this invention including the said aromatic polycarbonate resin. For example, antioxidants such as hindered phenols, esters, phosphate esters, and amines, UV absorbers such as benzotriazoles and benzophenones, light stabilizers such as hindered amines, aliphatic carboxylic acid esters, Examples thereof include internal lubricants such as paraffinic, silicone oil, polyethylene wax and the like, conventional flame retardants, flame retardant aids, mold release agents, antistatic agents and the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded. The raw materials and evaluation methods used in the following examples are as follows.

(1) Viscosity average molecular weight (Mv)
Using an Ubbelohde viscometer, the intrinsic viscosity [η] was measured at 20 ° C. with a 0.5 w / v% polycarbonate dichloromethane solution and a Huggins constant of 0.45, and was determined from the following equation.
[η] = 1.23 × 10 ⁻⁴ × (Mv) ^0.83

(2) Fluidity (Q value) (cc / s)
Using a Koka type flow tester, the flow rate of the resin at 280 ° C. from a nozzle having a load of 160 kgf / cm ² , a diameter of 1 mm and a length of 10 mm was measured.

(3) Impact resistance (Izod impact value (J / m))
A notched molded article for 3.2 mm thick Izod injection molded at 320 ° C. was measured according to ASTM D256.

(Example 1)
To 38 liters of 8.2% (w / w) sodium hydroxide aqueous solution, 4.67 kg (23.3 mol) of p, p-BPF manufactured by Honshu Chemical Industry Co., Ltd. and 1.33 kg of BPA manufactured by Mitsui Chemicals Co., Ltd. (5. 8 mol) and 39 g of hydrosulfite were added and dissolved. To this was added 10 liters of dichloromethane, and 3.69 kg of phosgene was blown in over 30 minutes while maintaining the solution temperature at 20 ° C. while stirring.

  After completion of the phosgene blowing, 7 liters of 8.2% (w / w) aqueous sodium hydroxide solution, 11 liters of dichloromethane and 286 g (1.9 mol) of p-tert-butylphenol (PTBP) were added and emulsified by vigorous stirring. Thereafter, 30 ml of triethylamine was added as a polymerization catalyst, and the mixture was polymerized for about 1 hour.

  The polymerization solution was separated into an aqueous phase and an organic phase, the organic phase was neutralized with phosphoric acid, and washing with pure water was repeated until the pH of the washing solution became neutral. The organic solvent was evaporated from the purified aromatic polycarbonate resin solution to obtain an aromatic polycarbonate resin powder.

The obtained aromatic polycarbonate resin powder was melt-kneaded at a cylinder temperature of 250 ° C. with a vented single screw extruder having a screw diameter of 50 mm, and pellets were prepared by strand cutting. As a result of viscosity measurement, fluidity and impact resistance measurement, the viscosity average molecular weight (Mv) was 19,300, the Q value was 70 × 10 ⁻² cc / s, and the Izod impact value was 520 J / m.

(Example 2)
In Example 1, the amount of p, p-BPF was changed to 2.80 kg (14.0 mol), the amount of BPA was changed to 3.20 kg (14.0 mol), and the amount of PTBP was changed to 240 g (1.6 mol). The same procedure as in Example 1 was performed to obtain aromatic polycarbonate resin pellets. Viscosity average molecular weight (Mv): 19,400, Q value: 41 × 10 ⁻² cc / s, Izod impact value: 540 J / m.

(Example 3)
In Example 1, except that the amount of p, p-BPF was changed to 1.08 kg (5.40 mol), the amount of BPA was 4.92 kg (21.6 mol), and the amount of PTBP was changed to 253 g (1.7 mol). The same procedure as in Example 1 was performed to obtain aromatic polycarbonate resin pellets. Viscosity average molecular weight (Mv): 17,100, Q value: 42 × 10 ⁻² cc / s, Izod impact value: 360 J / m.

Example 4
In Example 1, instead of p, p-BPF 4.67 kg, p, p-BPF 1.56 kg (7.8 mol), o, p-BPF 2.38 kg (11.9 mol), o, o-BPF 0.74 kg ( 3.7 mol) (both manufactured by Honshu Chemical Industry Co., Ltd.), except that the amount of BPA was changed to 1.33 kg (14.0 mol) and the amount of PTBP was changed to 128 g (0.85 mol). Aromatic polycarbonate resin pellets were obtained in the same manner as in Example 1. Viscosity average molecular weight (Mv): 19500, Q value: 50 × 10 ⁻² cc / s, Izod impact value: 260 J / m.

(Example 5)
p, p-BPF4.67kg (23.3mol) , BPA1.33kg (5.8mol), diphenyl carbonate (DPC) 7.16kg (33.5mol), and sodium bicarbonate 0.0126g (1.5 × 10 ^{- 4} mol) was placed in a 50 liter reactor equipped with a stirrer and distiller and heated to 200 ° C. over 1 hour under a nitrogen atmosphere of 760 Torr. Then, the degree of vacuum was adjusted to 100 Torr over 20 minutes, and the transesterification reaction was carried out by maintaining for 50 minutes under the conditions of 200 ° C. and 100 Torr. Further, the pressure was adjusted to 15 Torr over 10 minutes, and at the same time, the temperature was raised to 235 ° C. at a rate of 60 ° C./hr, and the temperature and pressure were maintained for 40 minutes to conduct a transesterification reaction.

  Thereafter, the temperature was adjusted to 1 Torr or less over 20 minutes, and at the same time, the temperature was raised to 260 ° C. at a rate of 90 ° C./hr. After completion of the reaction, nitrogen was blown into the reactor to increase the pressure, and the produced polycarbonate resin was extracted while being pelletized.

10.0 kg of this polycarbonate resin is vacuum-dried at 100 ° C. for 24 hours, p-toluenesulfonic acid n-hexyl is 10 times mol of sodium hydrogen carbonate in the resin, glycerol monostearate is 300 ppm of tris (2 , 4-di-tert-butylphenyl) phosphite was added at 25 ppm to the resin, kneaded by an extruder and pelletized to obtain pellets. The thus obtained aromatic polycarbonate resin pellets had a viscosity average molecular weight (Mv) of 19,100, a Q value of 71 × 10 ⁻² cc / s, and an Izod impact value of 510 J / m.

(Comparative Example 1)
In Example 1, except that p, p-BPF was not used, the amount of BPA was changed to 6.00 kg (26.3 mol), and the amount of PTBP was changed to 298 g (1.99 mol). To obtain an aromatic polycarbonate resin pellet. Viscosity average molecular weight (Mv): 14,500, Q value: 71 × 10 ⁻² cc / s, Izod impact value: 13 J / m.

(Comparative Example 2)
In Example 1, except that p, p-BPF was not used, BPA was changed to 6.00 kg (26.3 mol), and the amount of PTBP was changed to 195 g (1.30 mol). Group polycarbonate resin pellets were obtained. Viscosity average molecular weight (Mv): 19,500, Q value: 10 × 10 ⁻² cc / s, Izod impact value: 540 J / m.

(Comparative Example 3)
In Example 1, except that p, p-BPF was not used, the amount of BPA was changed to 6.00 kg (26.3 mol), and the amount of PTBP was changed to 67 g (0.45 mol). Aromatic polycarbonate resin powder was obtained by operation. The obtained aromatic polycarbonate resin powder was melt-kneaded at a cylinder temperature of 320 ° C. with a vented single screw extruder having a screw diameter of 50 mm, and pellets were prepared by strand cutting. Viscosity average molecular weight (Mv): 41,000, Q value: 0.5 × 10 ⁻² cc / s, Izod impact value: 1100 J / m.

(Comparative Example 4)
In Example 1, the amount of p, p-BPF was changed to 5.66 kg (28.3 mol), the amount of BPA was changed to 0.34 kg (1.49 mol), and the amount of PTBP was changed to 298 g (1.99 mol). In the same manner as in Example 1, a solid substance insoluble in dichloromethane was precipitated during the polymerization, and an aromatic polycarbonate resin powder soluble in dichloromethane was not obtained.

  Table 1 shows the physical property measurement results of the aromatic polycarbonate resins obtained in Examples 1 to 5 and Comparative Examples 1 to 4.

  The aromatic polycarbonate resin of the present invention can be suitably used in the field of application of optical materials because of its fluidity and impact resistance.

Claims (8)

At least one selected from the compound represented by the general formula (1) and at least one selected from the compound represented by the general formula (2) are carbonate-bonded by phosgene or carbonic acid diester, An aromatic polycarbonate resin for optical materials, wherein the molar fraction of the compound represented by formula (2) is 1 to 90%.


(In the formula, X is a single bond, an oxygen atom, a sulfur atom, a sulfone group, an alkylidene group having 2 to 10 carbon atoms, a cycloalkylidene group having 5 to 12 carbon atoms, an arylalkylidene group having 7 to 15 carbon atoms, or a fluorenylidene group. Or α, α, α ′, α′-tetramethylxylidene group.)
  The aromatic polycarbonate resin for an optical material according to claim 1, wherein the aromatic polycarbonate has a viscosity average molecular weight (Mv) of 15,000 to 40,000.   The aromatic polycarbonate resin for an optical material according to claim 1 or 2, wherein a molar fraction of 4,4'-methylenebisphenol in the compound represented by the general formula (2) is 99% or more.   The aromatic polycarbonate resin for optical materials according to any one of claims 1 to 3, wherein the compound represented by the general formula (1) is 2,2-bis (4-hydroxyphenyl) propane.   The aromatic polycarbonate resin for optical materials according to any one of claims 1 to 4, wherein an Izod impact value indicating impact resistance is 250 J / m or more. The aromatic polycarbonate resin for optical materials according to any one of claims 1 to 5, wherein the Q value indicating fluidity is 35 x ^10-2 cc / s or more.   The composition for light-guide plates containing the aromatic polycarbonate resin for optical materials in any one of Claims 1-6.   The molded article containing the aromatic polycarbonate resin for optical materials in any one of Claims 1-6.