JP2012067312A - Method for producing aromatic polycarbonate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing aromatic polycarbonate, which can enhance mechanical properties of molded products to a ductile range, can reduce the number of internal stressed point of sheet, can prevent transparency from lowering, and can minimize the number of white points generated under high-temperature high-humidity conditions.SOLUTION: There is provided a method for producing aromatic polycarbonate by melting and polycondensing an aromatic dihydroxy compound and diester carbonate in the presence of a transesterification catalyst, outside the scope surrounded by a curve connecting respective (Tc, Mn) points: (220, 4,000), (234, 4,810), (244, 6,510), (245, 7,400), (244, 9,210), (236, 12,050) and (226, 17,000), and two straight lines: Tc=220 and Mn=18,000, in the coordinates of a viscosity-average molecular weight Mn of reaction products as abscissa axis and the lowest temperature Tc (°C) being a temperature at the lowest temperature part inside polymerization equipment prescribed by the Mn as ordinate axis.

Description

  The present invention relates to a method for producing an aromatic polycarbonate. More specifically, the present invention relates to a method for producing an aromatic polycarbonate suitable for molding a molded article having little molding distortion and good durability and stability.

  Audio discs, laser discs (registered trademark), optical disc memories, magneto-optical discs and other recording media that record and / or reproduce information using laser beams, transparent sheets, lenses, etc., formability, machine Polycarbonate resins, which are superior to other resins in terms of mechanical strength and transparency, are used as materials. However, the excellent properties of the polycarbonate resin are also based on the non-crystallinity of the polycarbonate. When polycarbonate crystalline particles are mixed, the mechanical properties represented by the breaking strength and elongation of the molded product are lowered. One of the characteristics of this is that the ductility is lost and the impact strength is reduced, or optically, the internal image is distorted, the external image is distorted, the advantage of transparency is impaired, and the water is hydrolyzed at high temperature and high humidity. There are drawbacks in that it is susceptible to degradation and is likely to cause a decrease in molecular weight.

The polycarbonate resin is produced from an aromatic dihydroxy compound and a carbonate bond-forming precursor. The production method includes an interfacial polycondensation method in which phosgene is directly reacted as a carbonate bond-forming precursor, or a diester carbonate and heating. A melt polycondensation method in which a transesterification reaction is performed under reduced pressure is known. Among these, the melt polycondensation method has an advantage that a polycarbonate resin can be produced at a lower cost than the interfacial polycondensation method. However, in the case of a molded article, sheet or optical disk substrate using polycarbonate produced by the melt polycondensation method, it contains crystal particles inside, has low mechanical properties such as elongation at break, and has high ductility which is a characteristic of polycarbonate resin. This could not be realized, and there was a tendency that the impact strength was lowered, the advantage of transparency was impaired, or the crystal particle interface was easily hydrolyzed at a high temperature and high humidity, resulting in a decrease in molecular weight. Furthermore, in the case of a molded product molded from polycarbonate containing crystal particles even though it does not apparently contain crystal particles, mechanical properties tend to be low.
Foreign substances in polycarbonate are studied in Patent Document 1. This publication stipulates the amount of gelled product obtained by leaving a methylene chloride solution of polycarbonate through a 20 μm pore size filter and remaining on the filter. In the thermal decomposition at the time of molding of the polycarbonate obtained by the interfacial polycondensation method, a gelled product having a length of 1 cm is generated, and if this gelled product is large, refractive anomalies when the polycarbonate is formed into a sheet shape may increase. Are listed.

Compared with the interfacial polycondensation method, it is considered that a large number of foreign substances are generated in the polycarbonate obtained by the melt polycondensation method that receives a heat history for a long time at a higher temperature. However, regarding these various foreign substances, knowledge about the influence of specific foreign substances and content on polymer quality has not been obtained.
The polycarbonate resin has an X-ray diffraction pattern, a melting point of 310 ° C. or more, and a major axis of 50 μm or less (coarse particles exceeding 50 μm are hardly contained, and are hardly removed by a normal filter). It may contain fine crystalline particles. The content of the fine crystalline particles has a specific viscosity average molecular weight (hereinafter simply abbreviated as a molecular weight unless otherwise required) at the time when the transesterification catalyst is active in the melt polycondensation of the transesterification method. As the reactants history a temperature below a certain temperature defined by the molecular weight, they tend to increase. However, it has not been known in the past to reduce the fine crystalline particles to obtain a molded article with good mechanical properties or to improve the reliability of a transparent resin application, particularly an optical disk substrate over a long period of time. It was.

JP-A-2-135222

The present invention has been made in view of the above problems, and as a result of intensive investigations on the problems, the polycarbonate obtained by melt polycondensation in the presence of a transesterification catalyst has a breaking elongation of a molded product. It has been found that the decrease in mechanical properties such as is attributed to a fine crystalline material supplemented by a 3 μm filter and having an X-ray diffraction pattern. Further, it has been clarified that the fine crystalline particles are particularly insoluble in methylene chloride solvent and have a melting point of 310 ° C. or higher. Hereinafter, the fine crystalline particles having the X-ray diffraction pattern may be simply referred to as fine crystals or fine crystalline particles when there is no particular need for explanation.
Since the fine crystalline particles are insoluble in methylene chloride and have a melting point of 310 ° C. or higher, the conventional phosgene method is readily soluble in methylene chloride and has a melting point of at most 240 ° C., or a solid phase having a melting point of at most 285 ° C. It is different from the crystalline powder obtained by the polymerization method.

By setting the content of fine crystalline particles in the polycarbonate resin to 50 particles / kg or less, the mechanical properties typified by the breaking strength and elongation of the molded product molded from the resin surely show ductile fracture. A molded product having a high impact strength, which is one of the characteristics of polycarbonate, can be obtained. In addition, the number of strain points contained in substrates, sheets, lenses, etc. that are transparent molded products can be greatly reduced, and deterioration such as a decrease in molecular weight in a high temperature and high humidity atmosphere can also be controlled extremely effectively. For example, it has been clarified that high reliability can be maintained over a long period of time for optical discs, and that molded articles having good transparency and transparency can be obtained for sheets and other optical parts.
Here, the content of fine crystalline particles having an X-ray diffraction pattern captured by a nominal 3 μm filter is dissolved in 20 L of methylene chloride in 20 L of methylene chloride in a class 1000 or higher clean room to eliminate disturbance. The mixture was filtered under pressure using a Millipore filter, and the number of fine crystalline particles on the filter was observed and measured with a polarizing microscope at a magnification of 100.

  The present invention relates to mechanical properties typified by the breaking elongation of molded products formed from polycarbonate, and the number of internal strains and high temperature and high temperatures that reduce transparency in transparent sheets, lenses or optical disk substrates that are optical molded products. This is achieved by finding that the number of white spots generated under wet conditions is related to the content of fine crystalline particles having an X-ray diffraction pattern contained in the resin.

  An object of the present invention is to provide a method for producing an aromatic polycarbonate having a small content of fine crystalline particles having an X-ray diffraction pattern.

  Another object of the present invention is to increase the mechanical properties of a molded article to a ductile region, to reduce the number of strain points on the inner surface of a sheet or substrate, and to prevent a decrease in transparency, and at a high temperature and high humidity. An object of the present invention is to provide a method for producing an aromatic polycarbonate capable of controlling the white spot generated under the conditions to a minimum.

  Still other objects and advantages of the present invention will become apparent from the following description.

According to the present invention, the above objects and advantages of the present invention are:
Following formula (2)

(In the formula, R ¹ and R ² are each independently a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, or 6 to 20 carbon atoms. An aryl group of 7 to 20 carbon atoms, a cycloalkoxy group of 6 to 20 carbon atoms or an aryloxy group of 6 to 20 carbon atoms, m and n are each independently a number of 0 to 4, X is a single bond, oxygen atom, carbonyl group, alkylene group having 1 to 20 carbon atoms, alkylidene group having 2 to 20 carbon atoms, cycloalkylene group having 6 to 20 carbon atoms, cycloalkylidene group having 6 to 20 carbon atoms, carbon Represents an arylene group having 6 to 20 carbon atoms or an alkylene arylene alkylene group having 6 to 20 carbon atoms.)
An aromatic dihydroxy compound represented by:
Following formula (3)

(Here, Ar ¹ and Ar ² are each independently an optionally substituted aryl group having 6 to 10 carbon atoms, aralkyl group or alkyl group having 1 to 4 carbon atoms)
In the method of melt polycondensation with a carbonic acid diester represented by the following:
The viscosity average molecular weight Mn of the reaction mixture and the lowest temperature Tc (° C.) that is the temperature of the lowest temperature portion inside the polymerization apparatus defined by the viscosity average molecular weight Mn are Mn as the horizontal axis and Tc as the vertical axis. In coordinates, the points (Tc, Mn) = (220, 4,000), (234, 4, 810), (244, 6, 510), (245, 7, 400), (244, 9, 210), (236, 12,050), (226, 17,000) so as not to fall within a range surrounded by a curve that smoothly connects the points and two straight lines of Tc = 220 and Mn = 18,000, After melt polycondensation, (a) the main repeating unit is represented by the following formula (1)

(In the formula, the definitions of R ¹ , R ² , X, m and n are the same as in the above formula (2)).
Represented by
(C) the melt viscosity stability is 0.5% or less,
(D) the viscosity average molecular weight is 10,000 to 100,000;
(E) the terminal group substantially consists of an aryloxy group (A) and a phenolic OH group (B), the molar ratio (A) / (B) of both is 95/5 to 40/60, and (F) The content of fine crystalline particles collected in a filter having a nominal pore diameter of 3 μm and showing an X-ray diffraction pattern when a methylene chloride solution is obtained is 50 / kg polymer or less.
This is achieved by a method for producing an aromatic polycarbonate, characterized by producing an aromatic polycarbonate.

2 is an X-ray diffraction pattern of fine crystalline particles. It is a figure which shows the relationship between the viscosity average molecular weight Mn of an aromatic polycarbonate, and the minimum temperature (Tc) which does not produce | generate a fine crystalline particle.

First, the characteristic property (f) of the aromatic polycarbonate produced by the production method of the present invention will be described.
When the content of fine crystalline particles that show an X-ray diffraction pattern in a polycarbonate resin and are collected on a filter having a nominal pore diameter of 3 μm (hereinafter, the size may be 3 μm or more) exceeds 50 particles / kg, for example In addition, when a molded product is molded from the resin, the fracture elongation of the molded product may be so low as to show brittle fracture. Also, when a disk substrate is molded, in an information recording medium using the substrate, the particles and the above The optical distortion induced by the particles surely causes an error and reduces the reliability of the optical disk substrate. The fine crystalline particles can be identified as having a main peak at a diffraction angle (2θ) of 17.2 ° ± 0.3 ° in the X-ray diffraction pattern.
The content of the fine crystalline particles is preferably 50 particles / kg or less, more preferably 30 particles / kg or less, more preferably 10 particles / kg or less. By reducing the content, the mechanical properties of the molded product can be improved, and the reliability of the optical medium substrate can be raised to a high level.

Among these fine crystalline particles, those which are insoluble in a methylene chloride solvent and have a melting point of 310 ° C. or higher are preferably 40 particles / kg or less, more preferably 30 particles / kg or less, particularly preferably. By reducing the number to 10 / kg or less, the mechanical properties of the molded product can be improved, and the reliability of the optical medium substrate can be raised to a high level.
In the production of polycarbonate by melt polymerization, in order to reduce the content of organic and inorganic foreign matter including fine crystalline particles, it is usually judged that a method of removing with a filter is effective, but polycarbonate resin has a melt viscosity. Since it is high, it is necessary to increase the initial pressure during filtration, and it is necessary to gradually increase the filtration pressure as the filtration is continued. When the filtration pressure exceeds 200 atm, for example, it is necessary to replace the filter.

If the operation is interrupted due to filter replacement during the industrial operation, the quality of the polycarbonate will be different before and after that. In addition, if a filter with high filtration efficiency is used to remove such fine crystalline particles, the polymer flow will be biased in the filter case, resulting in variations in filter time, and changes in hue, side reactions such as crosslinking, etc. It tends to happen.
In the production of polycarbonate by melt polymerization, in order to reduce the content of fine crystalline particles having an X-ray diffraction pattern and a melting point of 310 ° C. or higher, the molecular weight of the reaction mixture is within a specific range during melt polymerization. In addition, the temperature of the reaction mixture should not be lowered below the temperature defined by the average molecular weight, and the temperature at the lowest temperature inside the polymerization apparatus where the bulk polycarbonate is in direct contact should not be lower than the specific temperature defined by the average molecular weight. Is one of the effective methods.

Conventionally, various polymerization apparatuses have been proposed to melt polymerize a high melt viscosity polycarbonate. However, in any polymerization apparatus, the main focus is on improving the stirring efficiency and increasing the polymerization rate. However, in such a high-viscosity polymerization apparatus, there is often a temperature difference inside, and it is not unusual that the temperature difference between the low temperature part and the high temperature part is 20 ° C to 50 ° C.
By keeping the temperature of the low temperature part inside the polymerization apparatus at or above the minimum temperature defined by the average molecular weight of the reaction mixture, the number of fine crystalline particles having the above X-ray diffraction pattern, particularly having a melting point of 310 ° C. or more is increased. Can be reduced.

In the graph in which the viscosity average molecular weight of the reaction mixture is Mn, the minimum temperature is Tc, Tc (° C.) is the vertical axis, and Mn is the horizontal axis, Mn is in the region of 3,000 to 18,000. (Tc, Mn) = (220, 4,000), (234, 4, 810), (244, 6, 510), (245, 7, 400), (244, 9, 210), (236, 12) , 050) and (226, 17,000), a curve like the attached graph (FIG. 2) is obtained.
In order to reduce the content of the fine crystalline particles, it is important that the temperature Tc of the low temperature part in the reaction system during polymerization does not fall within the range surrounded by the above curve and the horizontal axis. It is preferable to keep the minimum temperature in the range from the degree of polymerization to the degree of intermediate polymerization above the curve in this range.
The upper limit of the minimum temperature during polymerization can be appropriately selected from normal polymerization temperatures.However, if the polymerization temperature is too high, monomers and oligomers may volatilize in the low polymerization degree region and the molar balance may be lost. Since the reaction becomes conspicuous, the upper limit temperature is preferably 270 ° C. when Mn <6,000, 310 ° C. when 6,000 ≦ Mn ≦ 10,000, and 330 ° C. when Mn> 10,000.

Once the fine crystalline particles are produced once the viscosity average molecular weight is in the range of 3,000 to 18,000, the fine crystalline particles are heat-treated by the reaction temperature to rapidly increase the melting point, and in the normal melt polymerization temperature range, The melting point is raised so that it does not melt.
The lower the viscosity average molecular weight, the easier the reaction mixture will crystallize. However, when the viscosity average molecular weight is less than 3,000, the reaction temperature of ordinary melt polymerization is sufficiently higher than the melting point of fine crystalline particles. Formation of fine crystalline particles by crystallization of the mixture is not a problem.

  If the viscosity average molecular weight exceeds 18,000, the polymerization reaction is carried out at 255 ° C. or higher in order to secure the polymerization rate, and at the same time, the crystallization rate of the polycarbonate reaction mixture decreases, Alternatively, the problem of crystallization is reduced even when the reaction mixture is cooled. However, fine crystalline particles may be generated even in a normal molding process. In this case, the generation of fine crystalline particles is promoted by the retention of the polymer flow in the processing apparatus and the bisphenol A content in the polycarbonate. In order to suppress generation of fine crystalline particles during molding, it is effective to suppress the bisphenol A content to 10 to 50 ppm. More preferably, the range is 10 to 40 ppm, and particularly preferably 10 to 30 ppm. Even if the bisphenol A content is reduced to less than 10 ppm, the effect of suppressing the generation of fine crystalline particles is small. In order to realize such a bisphenol A content, it is also an effective means to perform high vacuum treatment for a short time in the final stage of the polycondensation reaction, that is, the stage after adding the melt viscosity stabilizer. For example, it is preferable to pass through a high vacuum of 13.3 Pa (0.1 mmHg) or less for 30 minutes. More preferably, a high vacuum treatment of 13.3 Pa to 6.7 Pa (0.1 to 0.05 mmHg) is applied for 1 to 20 minutes.

  Fine crystalline particles having an X-ray diffraction pattern and a melting point of 310 ° C. or higher, produced when the viscosity average molecular weight of the reaction mixture is between 3,000 and 18,000, It can be apparently melted and removed by raising the processing temperature to 327 ° C., which is the equilibrium melting point. However, in the case of a molded product obtained by molding a polycarbonate resin containing fine crystalline particles by such a method, there still remains a problem that the elongation at break is lower than that of a molded product not containing fine crystalline particles. is there.

  The aromatic polycarbonate produced by the production method of the present invention further comprises (g) particles having a major axis of 100 μm or less that are collected on a filter having a nominal pore diameter of 10 μm and are emitted by irradiation with ultraviolet rays having a wavelength of 380 nm. The content of is preferably 100 / kg polymer or less.

If the content of the light emitting particles as described above in the aromatic polycarbonate is less than the above value, the mechanical properties such as impact strength, strong elongation, etc. of the molded product are deteriorated, and the physical properties are exposed to long-term temperature and humidity. , Or abnormal flow orientation in the substrate, transparent sheet, lens or optical disk substrate, and the occurrence of a difference in refractive index, as well as hydrolysis that occurs under high-temperature and high-humidity conditions, or molecular weight and impact strength. It can be controlled to the minimum.
In the aromatic polycarbonate, when the content of a substance having a major axis of 100 μm or less that emits light by irradiation with ultraviolet rays having a wavelength of 380 nm exceeds 100 / kg, for example, the impact strength and strength of a molded product obtained from the resin are increased. The mechanical properties such as degree are low, and the mechanical properties are greatly deteriorated after being exposed to high temperature and high humidity for a long time. Comes to occur.
The content of the particles is preferably 80 / kg or less, more preferably 50 / kg or less. By reducing the content, the reliability of the optical medium substrate can be further increased.

In producing the melt-polymerized polycarbonate, for example, the following method can be used to reduce the amount of the luminous particles as described above.
i) lowering the polymerization temperature and reducing the temperature difference between the temperature of the bulk polycarbonate part and the exothermic part in the polymerization apparatus;
ii) coating the surface of the polycarbonate polymerization apparatus with an inert oxide layer, as previously proposed by the inventors,
iii) One effective method is to reduce the content of metal impurities in the polycarbonate by using a high-purity raw material.

  Various polymerization apparatuses have been proposed to melt polymerize a high melt viscosity polycarbonate. In any polymerization apparatus, the main focus is on improving the stirring efficiency and increasing the polymerization rate. However, in such a high-viscosity polymerization apparatus, due to high-efficiency stirring, shearing between the stirring blades or between the stirring blade and the polymerization apparatus main body becomes intense, causing shear heat generation. For this reason, compared with a polycarbonate bulk part, a sheared part may become as high as 100 degreeC or more.

  In order to make the temperature of the shearing portion low, it is preferable to make the bulk temperature of the polycarbonate as low as possible during the polymerization. For example, the usual polymerization temperature of 250 to 350 ° C. is decreased to 250 to 330 ° C., more preferably 250 to 300 ° C., and particularly preferably 250 to 280 ° C. Thus, it is preferable to reduce the heat generation at the sheared portion while lowering the polymerization temperature. In order to reduce the heat generation in the shearing section, it can be preferably achieved by controlling the stirring speed. When the polycarbonate is produced, the stirring speed can be controlled while detecting the temperature of the sheared part after the stage where the viscosity average molecular weight reaches at least 8,000 and the melt viscosity of the resin is increased.

It is preferred that the polycarbonate avoid contact with the hot metal surface above 350 ° C. before the transesterification catalyst loses activity with the melt viscosity stabilizer. More preferably, the temperature is not higher than 330 ° C., particularly preferably 320 ° C. or higher.
In addition, it is preferred that the polycarbonate not come into contact with such high temperature active metal surfaces.
The surface of the metal is liable to undergo decomposition and other side reactions in the polycarbonate under high temperature conditions. In order to inactivate the metal active surface, for example, means such as forming an oxide film on the metal active surface is recommended.
In this shear heat generation region, it is presumed that most of the object that emits light by irradiation with light at 380 nm is generated by the catalytic action of metal ions mixed in the metal surface or polycarbonate. In order to suppress the production of a luminescent substance by such a reaction mechanism, for example, as described above, it is one of effective techniques to coat the surface of the polymerization apparatus with, for example, an inert oxide layer or to reduce the content of metal impurities in polycarbonate. It is.

In the present invention, considering the influence on the durability, color tone and transparency of the polycarbonate produced, transition metal elements such as Fe, Cr, Mn, Ni, Pb, Cu, Pd contained as impurities in the raw material, Al, It is recommended that the content of trace metal elements of metals such as Ti and amphoteric elements be 50 ppb or less, more preferably 10 ppb or less.
In order to obtain an aromatic polycarbonate having superior durability, the content of alkali metal element and / or alkaline earth metal element having a large transesterification capacity contained in the aromatic dihydroxy compound and the carbonic acid diester is 0 to 60 ppb. Preferably there is.
Further, in order to obtain an aromatic polycarbonate having superior durability, the content of alkali metal element and / or alkaline earth metal element in the aromatic dihydroxy compound and carbonic acid diester is 80 ppb or less, and the transition metal element concentration is 10 ppb. The following is preferable.

Furthermore, the above-mentioned metal contained in a carbonic acid diester and an aromatic dihydroxy compound and the amphoteric element-containing concentration are preferably 20 ppb or less.
The lower the content of such transition metal elements, metals, or amphoteric elements as raw materials, the better, but by using aromatic dihydroxy compounds and carbonic acid diesters that are 10 ppb or less, which is the limit of conventional technology, excellent durability An aromatic polycarbonate having properties can be obtained.

In the present invention, in order to obtain aromatic dihydroxy compounds and carbonic acid diesters with a reduced content of transition metals, metals, amphoteric impurities, known purification methods such as distillation, extraction, recrystallization, sublimation, etc. Various purification methods can be used. Further, it is more preferable to combine the above purification methods in various ways.
Further, in order to obtain a polycarbonate with less metal impurities in the present invention, it is preferable to use a high-purity solvent having a very low content of metal impurities in the purification of such raw materials. For example, a solvent for electronic industry can be used. .

The aromatic polycarbonate of the present invention mainly comprises the repeating unit represented by the formula (1).
In the formula (1), the definitions of R ¹ and R ² are as described above.
Examples of the halogen atom include fluorine, chlorine, bromine and the like.

The alkyl group having 1 to 20 carbon atoms may be linear or branched. Examples thereof include methyl, ethyl, propyl, butyl, octyl, decyl and the like. The alkoxy group having 1 to 20 carbon atoms may be linear or branched, and examples thereof include methoxy, ethoxy, propoxy, butoxy, octyloxy, decyloxy and the like. Examples of the cycloalkyl group having 6 to 20 carbon atoms include cyclohexyl and cyclopentyl. Examples of the aryl group having 6 to 20 carbon atoms include phenyl, tolyl, 4-t-butylphenyl, naphthyl and the like. Examples of the aralkyl group having 7 to 20 carbon atoms include cumyl (Ph—C (CH ₃ ) ₂ —) benzyl, phenethyl and the like. Examples of the C6-C20 cycloalkoxy group include cyclohexyloxy and cyclopentyloxy. Examples of the aryloxy group having 6 to 20 carbon atoms include phenyloxy, tolyloxy, 4-t-butylphenyloxy, naphthyloxy and the like.
The definition of X is also as described above.

The alkylene group having 1 to 20 carbon atoms may be linear or branched.
Examples thereof include methylene, 1,2-ethylene, 1,3-propylene, 1,4-butylene, 1,10-decylene and the like.
Examples of the alkylidene group having 2 to 20 carbon atoms include ethylidene, 2,2-propylidene, 2,2-butylidene, and 3,3-hexylidene.
Examples of the cycloalkylene group having 6 to 20 carbon atoms include 1,4-cyclohexylene and 2-isopropyl-1,4-cyclohexylene.
Examples of the cycloalkylidene group having 6 to 20 carbon atoms include cyclohexylidene and isopropylcyclohexylidene.
Examples of the arylene group having 6 to 20 carbon atoms include 1,4-phenylene, 4,4′-biphenylene, 2-t-butyl-1,4-phenylene and the like.
Examples of the alkylene-arylene-alkylene group having 6 to 20 carbon atoms include m-diisopropylphenylene group.
M and n are each independently 0, 1, 2, 3 or 4.

In the above formula (1), X is preferably an alkylidene group having 2 to 20 carbon atoms, and n and m are both zero. In particular, X is preferably a cyclohexylidene group or a 2,2-propylidene group, and particularly preferably a 2,2-propylidene group.
The aromatic polycarbonate preferably occupies at least 85 mol% of the repeating unit represented by the above formula (1) based on all repeating units.
The aromatic polycarbonate produced by the production method of the present invention is produced by melt polycondensation of an aromatic dihydroxy compound and a carbonic acid diester in the presence of a transesterification catalyst.
As an aromatic dihydroxy compound, the following formula (2)

Here, the definitions of R ¹ , R ² , X, n, and m are the same as in formula (1).
The compound represented by these is used.

  Representative examples of such aromatic dihydroxy compounds include 4,4′-dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3,5-dimethylphenyl) methane, 1,1-bis. (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane (commonly called bisphenol A), 2,2-bis (4 -Hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 2, 2-bis (3-isopropyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-phenylphenyl) Propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,4-bis (4-hydroxyphenyl) -2-methylbutane, 2,2-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1- Bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2,2 ′, 2′-tetrahydro-3,3,3 ′, 3 '-Tetramethyl-1,1'-spirobis [1H-indene] -6,6'-diol, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bi (4-hydroxy-3-methylphenyl) fluorene, α, α′-bis (4-hydroxyphenyl) -o-diisopropylbenzene, α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene, α, α′-bis (4-hydroxyphenyl) -p-diisopropylbenzene, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantane, 4,4′-dihydroxydiphenylsulfone, 4,4′-dihydroxy Examples thereof include diphenyl sulfoxide, 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxydiphenyl ketone, 4,4′-dihydroxydiphenyl ether, and these can be used alone or in admixture of two or more.

  Among them, bisphenol A, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3-methylbutane 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) -3 , 3,5-trimethylcyclohexane, 2,2,2 ′, 2′-tetrahydro-3,3,3 ′, 3′-tetramethyl-1,1′-spirobis [1H-indene] -6,6′- A homopolymer obtained from at least one bisphenol selected from the group consisting of diol and α, α'-bis (4-hydroxyphenyl) -m-diisopropylbenzene A copolymer of bisphenol A and 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and bisphenol A, 2,2-bis {(4- A copolymer with hydroxy-3-methyl) phenyl} propane or α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene is preferably used.

In the present invention, aromatic dihydroxy compounds other than the above formula (2), specifically hydroquinone, resorcinol, catechol and the like may be copolymerized.
In producing polycarbonate by the reaction by the melt polycondensation method, an antioxidant such as a terminal terminator or a sterically hindered phenol may be used as necessary. The polycarbonate may be a branched polycarbonate copolymerized with a trifunctional or higher polyfunctional aromatic compound, or may be a polyester carbonate copolymerized with an aromatic or aliphatic difunctional carboxylic acid. The mixture which mixed 2 or more types of the obtained polycarbonate may be sufficient.
Examples of the carbonic acid diester include the following formula (3):

Here, Ar ¹ and Ar ² are each independently an optionally substituted aryl group having 6 to 10 carbon atoms, an aralkyl group, or an alkyl group having 1 to 4 carbon atoms,
The compound represented by these can be mentioned.
In the formula (3), a carbonic acid diester in which Ar ¹ and Ar ² are the same group is preferable.
Examples of the carbonic acid diester include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, bis (diphenyl) carbonate, diethyl carbonate, and dibutyl carbonate. Of these, diphenyl carbonate is preferred.
As the transesterification catalyst, a) a nitrogen-containing basic compound and / or a phosphorus-containing basic compound (hereinafter abbreviated as NCBA) and b) an alkali metal compound (hereinafter abbreviated as AMC) are preferably used.

Examples of the nitrogen-containing basic compound include tetramethylammonium hydroxide (Me ₄ NOH), benzyltrimethylammonium hydroxide (φ-CH ₂ (Me) ₃ NOH), etc., ammonium having an alkyl, aryl, alkylaryl group, etc. Hydroxides; basic ammonium salts having alkyl, aryl, alkylaryl groups, such as tetramethylammonium acetate, tetraethylammonium phenoxide, tetrabutylammonium carbonate, benzyltrimethylammonium benzoate; triethylamine, dimethylbenzylamine, etc. Tertiary amine, or tetramethylammonium borohydride (Me ₄ NBH ₄ ), tetrabutylammonium borohydride (Bu ₄ NBH ₄ ) And basic salts such as tetramethylammonium tetraphenylborate (Me ₄ NBPh ₄ ).

Examples of the phosphorus-containing basic compound include alkyl, aryl, and alkylaryl groups such as tetrabutylphosphonium hydroxide (Bu ₄ POH) and benzyltrimethylphosphonium hydroxide (φ-CH ₂ (Me) ₃ POH). Examples include phosphonium hydroxides or basic salts such as tetramethylphosphonium borohydride (Me ₄ PBH ₄ ), tetrabutylphosphonium borohydride (Bu ₄ PBH ₄ ), tetramethylphosphonium tetraphenylborate, and (Me ₄ PBPh ₄ ). be able to.

The NCBA is preferably used in such a ratio that the basic nitrogen atom or basic phosphorus atom is 1 × 10 ⁻⁵ to 1 × 10 ⁻³ chemical equivalent per 1 mol of the aromatic dihydroxy compound. A more preferable use ratio is a ratio of 2 × 10 ^{−5 to} 5 × 10 ⁻⁴ chemical equivalent with respect to the same standard. A particularly desirable ratio is a ratio of 5 × 10 ^{−5 to} 5 × 10 ⁻⁴ chemical equivalent with respect to the same standard.
In particular, at this time, in order to improve the hue of the obtained polycarbonate, the amount of NCBA compound used is the total amount of iron contained in the raw material carbonic acid diester and aromatic dihydroxy compound; Fe ^* (expressed in wtppb) {20 × It has been found effective when used so as not to exceed (Fe ^* ) + 200} × 10 ⁻⁶ chemical equivalents. Particularly preferred is a range not exceeding the chemical equivalent of {20 × (Fe ^* ) + 150} × 10 ⁻⁶ .

Furthermore, in the present invention, the effect of reducing impurities in the raw material is polymer color tone,
In order to achieve stability, AMC is used in combination with NCBA. The AMC compound is preferably used in the range of 1 × 10 ^{−8 to} 5 × 10 ⁻⁶ chemical equivalent as an alkali metal element with respect to 1 mol of the aromatic dihydroxy compound. By using the catalyst in such a quantitative ratio, it is easy to generate a branching reaction, a main chain cleavage reaction, or a foreign matter in the apparatus during the molding process without impairing the end-capping reaction or the polycondensation reaction rate. This is preferable because undesirable phenomena such as formation and burning can be effectively suppressed.
If it deviates from the above range, there are problems such as adversely affecting the physical properties of the obtained polycarbonate, and the ester exchange reaction does not proceed sufficiently, and a high molecular weight polycarbonate cannot be obtained.

Examples of AMC include alkali metal hydroxides, hydrocarbon compounds, carbonates, acetates, stearates, benzoates and other carboxylates, nitrates, nitrites, sulfites, cyanates, thiocyanates , Borohydride, hydrogen phosphate, bisphenol, phenol salt and the like.
Specific examples include sodium hydroxide, potassium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium acetate, rubidium nitrate, lithium nitrate, sodium nitrite, sodium sulfite, sodium cyanate, potassium cyanate, sodium thiocyanate, thiocyanate. Potassium phosphate, cesium thiocyanate, sodium stearate, sodium borohydride, potassium borohydride, lithium borohydride, sodium phenyl borohydride, sodium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, bisphenol A di Examples include sodium salts, monopotassium salts, sodium potassium salts, and potassium potassium phenols.

In addition, as desired, as an alkali metal compound, (a) art complex alkali metal salt of group 14 element of periodic table or (i) oxo acid of group 14 element of periodic table described in JP-A-7-268091 Alkali metal salts can be used. Here, the element of Group 14 of the periodic table means silicon, germanium, and tin.
By using such an alkali metal compound as a catalyst for the polycondensation reaction, there is an advantage that the polycondensation reaction can be rapidly and sufficiently advanced. Moreover, an undesirable side reaction such as a branching reaction that proceeds during the polycondensation reaction can be suppressed to a low level.

  In the polycondensation reaction of the present invention, together with the above catalyst, if necessary, at least one compound selected from the group consisting of oxoacids of group 14 elements of the periodic table, oxides and alkoxides and phenoxides of the same elements is supported. It can coexist as a catalyst. By using these cocatalysts in a specific ratio, the end-blocking reaction, the branching reaction that tends to occur during the polycondensation reaction without impairing the polycondensation reaction rate, the main chain cleavage reaction, It is preferable for the purpose of the present invention because it is possible to effectively suppress undesirable phenomena such as generation and burning of foreign substances.

Examples of oxo acids belonging to Group 14 of the periodic table include silicic acid, stannic acid, and germanic acid.
Examples of the oxide of Group 14 of the periodic table include silicon dioxide, tin dioxide, germanium dioxide, silicon tetramethoxide, silicon tetraphenoxide, tetraethoxytin, tetranonyloxytin, tetraphenoxytin, tetrabutoxygermanium, tetraphenoxy. Germanium and condensates thereof can be mentioned.
The co-catalyst is preferably present at a ratio such that an element of Group 14 of the periodic table is 50 mole atoms or less per mole atom of the alkali metal element in the polycondensation reaction catalyst. If the co-catalyst is used in such a proportion that the metal element exceeds 50 mole atoms, the polycondensation reaction rate is undesirably slowed.
More preferably, the cocatalyst is present at a ratio of 0.1 to 30 mol atoms of Group 14 element as a cocatalyst per mol atom of alkali metal element of the polycondensation reaction catalyst.

The amount of these polymerization catalysts used in the present invention is 1 × 10 ^{−8 to} 5 × 10 ⁻⁶ chemical equivalent, preferably 5 × 10 ⁻⁸ , relative to 1 mol of the aromatic dihydroxy compound when an alkali metal compound is used. It is selected in the range of ˜3 × 10 ⁻⁶ chemical equivalent, particularly preferably 7 × 10 ⁻⁸ to 2 × 10 ⁻⁶ chemical equivalent.

  In the melt polymerization method, the aromatic dihydroxy compound and the carbonic acid diester as described above are stirred with heating in the presence of the transesterification catalyst as described above under a normal pressure and / or a reduced pressure nitrogen atmosphere to produce the alcohol or aromatic product. It is carried out by distilling the group monohydroxy compound. Although the reaction temperature varies depending on the boiling point of the product, etc., it is usually in the range of 120 to 350 ° C in order to remove the alcohol or aromatic monohydroxy compound produced by the reaction, but the content of fine crystalline particles in the polycarbonate is reduced. Therefore, it is important that the temperature of the reaction mixture does not fall below Tc from the point where the molecular weight of the reaction mixture exceeds 7,000 so that it does not come into direct contact with the reactor part below Tc. In addition, in order to reduce the generation of fine crystalline particles in the molding process, it is also effective to suppress the content of bisphenol A that promotes the generation of fine crystalline particles to 10 to 40 ppm. In the latter stage of the reaction, the system is reduced in pressure to facilitate distillation of the alcohol or aromatic monohydroxy compound produced. The internal pressure of the system in the late stage of the reaction is preferably 133.3 Pa (1 mmHg) or less, more preferably 66.7 Pa (0.5 mmHg) or less.

The aromatic polycarbonate produced by the production method of the present invention has a melt viscosity stability of 0.5% or less.
The melt viscosity stability is evaluated by the absolute value of the change in melt viscosity measured at 30 ° C. for 30 minutes under a nitrogen stream at a shear rate of 1 rad / sec, and is expressed as the rate of change per minute. It is essential to set this value to 0.5% or less. If this value is large, hydrolysis degradation, molecular weight reduction or coloring of the polycarbonate may be promoted. In order to ensure practical hydrolysis resistance and the like, it is sufficient to set this value to 0.5%. Therefore, it is preferable to stabilize the melt viscosity using a melt viscosity stabilizer after polymerization.

The melt viscosity stabilizer in the present invention also has an action of deactivating part or all of the activity of the polymerization catalyst used in the production of the polycarbonate.
As a method for adding the melt viscosity stabilizer, for example, the polymer may be added while the polymer is in a molten state after polymerization, or may be added after being re-dissolved after pelletizing the polycarbonate. In the former case, a melt viscosity stabilizer may be added while the polycarbonate, which is a reaction product in the reaction vessel or the extruder, is in a molten state, and the polycarbonate obtained after the polymerization is added from the reaction vessel. A melt viscosity stabilizer may be added and kneaded while being pelletized through.

  A known agent can be used as the melt viscosity stabilizer. Sulfonic acid compounds such as organic sulfonic acid salts, organic sulfonic acid esters, organic sulfonic acid anhydrides, organic sulfonic acid betaines, etc., because they have a great effect on improving the physical properties such as hue, heat resistance and boiling water resistance of the resulting polymer. Of these, phosphonium salts of sulfonic acid and / or ammonium salts of sulfonic acid are preferably used. Among them, particularly preferred examples include dodecylbenzenesulfonic acid tetrabutylphosphonium salt and paratoluenesulfonic acid tetrabutylammonium salt.

  The aromatic polycarbonate produced by the production method of the present invention has a viscosity average molecular weight in the range of 10,000 to 100,000. As an injection-molded article, for example, a disk substrate material, the viscosity average molecular weight (Mn) is preferably 10,000 to 22,000, more preferably 12,000 to 20,000, and particularly preferably 13,000 to 18,000. A polycarbonate having such a viscosity-average molecular weight is preferable because it provides sufficient strength as an optical material and has good melt fluidity during molding and does not cause molding distortion. In applications such as extruded products, such as sheets, the viscosity average molecular weight is preferably 17,000 to 100,000, more preferably 20,000 to 80,000.

  In the aromatic polycarbonate produced by the production method of the present invention, the terminal group substantially consists of an aryloxy group (A) and a phenolic hydroxyl group (B), and the molar ratio (A) / ( B) is 95/5 to 40/60. Preferably, the phenolic end group concentration is 40 mol% or less, more preferably 30 mol% or less. By containing the phenolic end group in such a quantitative ratio, the object of the present invention can be achieved more suitably, and the moldability of the composition (made by mold fouling, mold release; hereinafter simply referred to as moldability). Will also improve.

On the other hand, even if the phenolic end group concentration is decreased from 5 mol%, the further improvement of the physical properties of the composition is small, and when a phenolic end group concentration of 60% or more is introduced, it is not preferable for the purpose of the present invention. Is obvious from the above discussion.
As the aryloxy group, for example, a hydrocarbon group having 1 to 20 carbon atoms and a substituted or unsubstituted phenyloxy group are preferably selected. From the viewpoint of thermal stability of the resin, a phenyloxy group having a tertiary alkyl group, a tertiary aralkyl group or an aryl group or an unsubstituted phenyloxy group is preferred as a substituent. Those having a benzyl type hydrogen atom can be used if they have a desired purpose such as improvement of actinic radiation resistance, but they should be avoided from the viewpoint of stability against heat, thermal aging, thermal decomposition and the like.

Specific examples of preferred aryloxy groups include phenoxy group, 4-t-butylphenyloxy group, 4-t-amylphenyloxy group, 4-phenylphenyloxy group, 4-cumylphenyloxy group, and the like. Preferred is a phenoxy group.
In the interfacial polymerization method, the terminal phenolic end groups are suppressed to a low concentration by the molecular weight regulator, but in the melt polymerization method, those having a phenolic end group concentration of 60 mol% or more are produced chemically. Since it is easy, it is necessary to actively reduce phenolic end groups.

That is, in order to bring the phenolic end group concentration within the above range, it can be advantageously achieved by the method 1) or 2) described below.
1) Polymerization raw material charging molar ratio control method: The molar ratio of carbonic acid diester / aromatic dihydroxy compound at the time of polymerization reaction charging is increased. For example, it is set between 1.03 and 1.10 in consideration of the characteristics of the polymerization reactor.
2) End-capping method: At the end of the polymerization reaction, for example, according to the method described in US Pat. No. 5,696,222, the terminal hydroxyl group is blocked by adding the salicylic acid ester-based compound described in the above document.

When the terminal hydroxyl group is capped with a salicylic acid ester compound, the amount of the salicylic acid ester compound used is 0.8 to 10 mol, more preferably 0.8 to 5 mol per terminal hydroxyl group per chemical equivalent before the capping reaction. Particularly preferably, it is in the range of 0.9 to 2 mol. By adding in such a quantitative ratio, 80% or more of the phenolic end groups can be suitably sealed. Moreover, when performing this sealing reaction, it is preferable to use the catalyst as described in the said US patent.
The reduction of the phenolic end group concentration is preferably carried out at a stage prior to deactivation of the polymerization catalyst.

  As the salicylic acid ester compound, a salicylic acid ester compound described in US Pat. No. 5,696,222 can be preferably used. Specifically, 2-methoxycarbonylphenyl aryl carbonate such as 2-methoxycarbonylphenyl-phenyl carbonate; 2 2-methoxycarbonylphenyl-alkyl carbonate such as methoxycarbonylphenyl-lauryl carbonate; 2-ethoxycarbonylphenyl-aryl carbonate such as 2-ethoxycarbonylphenyl-phenyl carbonate; 2-ethoxy such as 2-ethoxycarbonylphenyl-octyl carbonate (2'-methoxy) of aromatic carboxylic acids such as carbonylphenyl-alkyl carbonate; (2-methoxycarbonylphenyl) benzoate Rubonirufeniru) ester; and (2-methoxycarbonylphenyl) stearate, bis (2-methoxycarbonylphenyl) such aliphatic carboxylic acid ester of adipate and the like.

  When the aromatic polycarbonate produced by the production method of the present invention is used to mold various molded products, conventionally known processing stabilizers, heat stabilizers, antioxidants, ultraviolet absorbers are used depending on the application. Further, an antistatic agent, a flame retardant, a release agent, and the like can be added.

  For example, a thermal stabilizer can be blended with the aromatic polycarbonate produced by the production method of the present invention in order to prevent a decrease in molecular weight or a deterioration in hue. Examples of such heat stabilizers include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid and esters thereof. Trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite 4,4′-biphenylenediphosphosphinic acid tetrakis (2,4-di-tert-butylphenyl), bis (2,4-di-tert-butylphenyl) pentaerythryl diphosphite, trimethyl phosphate and benzenephosphone Dimethyl acid is preferably used. These heat stabilizers may be used alone or in admixture of two or more. The amount of the heat stabilizer is preferably 0.0001 to 1 part by weight, more preferably 0.0005 to 0.5 part by weight, and more preferably 0.001 to 0.005 parts by weight based on 100 parts by weight of the aromatic polycarbonate of the present invention. 1 part by weight is more preferred.

  In addition, a release agent may be blended in the aromatic polycarbonate produced by the production method of the present invention within a range that does not impair the object of the present invention in order to further improve the releasability from the mold during melt molding. Is also possible. Examples of the release agent include olefin wax, olefin wax containing carboxyl group and / or carboxylic anhydride group, silicone oil, organopolysiloxane, higher fatty acid ester of mono- or polyhydric alcohol, paraffin wax, Examples include beeswax. The amount of the release agent is preferably 0.01 to 5 parts by weight with respect to 100 parts by weight of the aromatic polycarbonate of the present invention.

  As the higher fatty acid ester, for example, a partial ester or a total ester of a monovalent or polyhydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms is preferable. As such partial ester or total ester of monohydric or polyhydric alcohol and saturated fatty acid, for example, stearic acid monoglyceride, stearic acid triglyceride, pentaerythritol tetrastearate is preferably used. The amount of the release agent is preferably 0.01 to 5 parts by weight with respect to 100 parts by weight of the aromatic polycarbonate of the present invention.

Furthermore, the aromatic polycarbonate produced by the production method of the present invention includes a solid filler and / or a thermoplastic resin other than the aromatic polycarbonate of the present invention in order to improve rigidity and the like within a range not impairing the object of the present invention. Can be formulated, thereby providing an aromatic polycarbonate composition.
Examples of the solid filler include plate-like or granular inorganic fillers such as talc, mica, glass flakes, glass beads, calcium carbonate, and titanium oxide; glass fiber, glass milled fiber, wollastonite, carbon fiber, aramid fiber, Examples thereof include fibrous fillers such as metal-based conductive fibers; and organic particles such as crosslinked acrylic particles and crosslinked silicone particles. The amount of these solid fillers is preferably 1 to 150 parts by weight, more preferably 3 to 100 parts by weight, based on 100 parts by weight of the aromatic polycarbonate of the present invention.

The inorganic filler usable in the present invention may be surface-treated with a silane coupling agent or the like. By this surface treatment, good results such as suppression of the decomposition of the aromatic polycarbonate can be obtained.
Examples of the thermoplastic resin include polyamide resin, polyimide resin, polyetherimide resin, polyurethane resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, polyolefin resin such as polyethylene and polypropylene, polyethylene terephthalate, polybutylene terephthalate. Polyester resin, polycarbonate resin, amorphous polyarylate resin, polystyrene resin, acrylonitrile / styrene copolymer (AS resin), acrylonitrile / butadiene / styrene copolymer (ABS resin), polymethacrylate resin, phenol resin, epoxy Examples of the resin include resins.
These thermoplastic resins can be used in an amount of 10 to 150 parts by weight based on 100 parts by weight of the aromatic polycarbonate produced by the production method of the present invention.

  The aromatic polycarbonate produced by the production method of the present invention and the aromatic polycarbonate composition using the same are suitably used as a material for a substrate of an optical information recording medium. An optical information recording medium comprising a substrate made of an aromatic polycarbonate produced by the production method of the present invention and an aromatic polycarbonate composition using the same, such as a compact disc (CD), CD-ROM, CD-R, CD- High-density optical disks represented by digital versatile disks (DVD-ROM, DVD-Video, DVD-Audio, DVD-R, DVD-RAM, etc.) such as RW, magnet optical disk (MO), etc. are high for a long time. Reliability is obtained. It is particularly useful for high density optical discs such as digital versatile discs.

  In addition, the aromatic polycarbonate produced by the production method of the present invention and the sheet from the aromatic polycarbonate composition using the same are sheets having excellent adhesiveness and printability, and take advantage of the properties of electrical parts and building materials. Widely used in parts, automobile parts, etc. Specifically, glazing products for window materials such as various window materials such as general houses, gymnasiums, baseball domes, vehicles (construction machinery, automobiles, buses, bullet trains, train cars, etc.), and various side panels (sky domes, top lights, Arcades, condominium lumbar panels, road side panels), window materials for vehicles, OA equipment displays and touch panels, membrane switches, photo covers, polycarbonate resin laminates for aquariums, front panels and Frennel lenses for projection TVs and plasma displays. It is useful for optical applications such as an optical card, a liquid crystal cell in combination with an optical disk or a polarizing plate, and a phase difference correction plate. The thickness of the sheet is not particularly limited, but is usually 0.1 to 10 mm, preferably 0.2 to 8 mm, and particularly preferably 0.2 to 3 mm. In addition, various processing treatments that add new functions to such sheets (various laminating treatments for improving weather resistance, scratch resistance improving treatments for improving surface hardness, surface wrinkle processing, semi-opaque processing, etc.) ) May be applied.

  In order to mix | blend each said component with the aromatic polycarbonate manufactured by the manufacturing method of this invention, arbitrary methods are employ | adopted. For example, a method of mixing with a tumbler, a V-type blender, a super mixer, a nauter mixer, a Banbury mixer, a kneading roll, an extruder, or the like is appropriately used. The aromatic polycarbonate resin composition thus obtained can be formed into a sheet by the melt extrusion method as it is or after being once pelletized by a melt extruder.

  The aromatic polycarbonate produced by the production method of the present invention is a sintered metal having a filtration accuracy of 10 μm when it is in a molten state in an extrusion process (pelletizing process) for producing pellets for injection molding after being produced by a melt polymerization method. It is preferable to remove foreign matters by passing the filter. If necessary, it is also preferable to add additives such as phosphorus-based antioxidants. In any case, it is necessary for the raw material resin before injection molding to keep the content of foreign matters, impurities, solvents, etc. as low as possible.

  An injection molding machine (including an injection compression molding machine) is used when an optical disk substrate is produced from an aromatic polycarbonate produced by the production method of the present invention and an aromatic polycarbonate composition using the same. This injection molding machine may be generally used, but it has low adhesion to the resin as a cylinder or screw from the viewpoint of suppressing the generation of carbides and increasing the reliability of the disk substrate, and also has corrosion resistance and wear resistance. It is preferable to use a material made of a material exhibiting properties. As conditions for injection molding, a cylinder temperature of 300 to 400 ° C. and a mold temperature of 50 to 140 ° C. are preferable, and an optically excellent optical disk substrate can be obtained. The environment in the molding process is preferably as clean as possible in view of the object of the present invention. It is also important to take into consideration that the material used for molding is sufficiently dried to remove moisture, and that no retention that causes decomposition of the molten resin occurs.

  The aromatic polycarbonate produced by the production method of the present invention and the aromatic polycarbonate composition using the same may be used for any application, and various molded products such as electronic / communication equipment, OA equipment, lenses, prisms, optical disk substrates. , Optical parts such as optical fibers; electronic / electrical parts such as household appliances, lighting members, heavy electrical members; machine parts such as vehicle interior / exterior, precision machinery, insulation materials; medical materials, safety / protection materials, sports / leisure goods, homes It can be used for miscellaneous parts such as goods; containers / packaging materials, display / decorative materials, etc. Further, it can be suitably used as a composite material with other resins and organic / inorganic materials.

  The present invention will be further described below with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” means parts by weight.

Analytical method The test method of the aromatic polycarbonate manufactured by the Example and the comparative example was based on the following method.

1) Viscosity average molecular weight (Mn): As a methylene chloride solution, it was determined from the intrinsic viscosity ([η]) measured with an Ubbelohde viscometer at 20 ° C. by the following equation.
[Η] = 1.23 × 10 ⁻⁴ × Mn ^0.83

2) Apparatus for quantitative determination of metal impurity content; ICP-MS, SPQ9000 manufactured by Seiko Electronics Industry Co., Ltd.
Sample concentration: A sample (0.5 g) was dissolved in 25 g of isopropyl alcohol (polymerization raw material: bisphenol A, diphenyl carbonate used for quantification) or N-methylpyrrolidone (NMP) (used for quantification of polycarbonate) for electronic industry. Standard sample calibration curve Was quantified.

3) measurement of the number of fine crystalline particles;
In a clean room of class 1000 or higher, 1 kg of polycarbonate resin is dissolved in 20 L of methylene chloride, filtered under pressure through a 3 μm millipore filter, and the number of crystalline fine particles on the filter is observed and measured at a magnification of 100 times with a polarizing microscope. did.

4) Measurement of X-ray diffraction pattern; apparatus; RAD-rB, Rigaku Corporation
Measurement conditions: Cu K ALPHA 1/50 kV / 200 mA
Counter; Scintillation counter divergence slit; 0.5 °
Scattering slit: 0.5 °
Light receiving slit; 0.6mm
Scan mode; continuous scan speed; 4 ° / min
Scan step; 0.02 °
Scanning range; 5-50 °

5) Melt viscosity stability Measured for 30 minutes at 300 ° C with a shear rate of 1 rad / sec using a RAA flow analysis device manufactured by Rheometrics, and divided the absolute value of the change in viscosity by the melt viscosity. The rate of change per minute was determined, and this value was taken as the melt viscosity stability. In order for the aromatic polycarbonate to have good long-term stability, this value should not exceed 0.5%.

6) Hue measurement;
The hue (color L, a, b) of the color sample plate obtained by molding under conditions of a cylinder temperature of 300 ° C. and a mold temperature of 80 ° C. by an injection molding machine was measured and evaluated. The apparatus used was a Z-1001DP color difference meter manufactured by Nippon Denshoku Co., Ltd.

7) Phenolic terminal group concentration, quantification of aryloxy terminal number 0.02 g of a polymer sample was dissolved in 0.4 ml of deuterated chloroform and ¹ H-NMR (EX-270 manufactured by JEOL Ltd.) was used at 20 ° C. The phenolic end group concentration was measured.
The number of aryloxy terminal groups was calculated as the difference between the total number of terminal groups and the number of phenolic terminal groups determined from the intrinsic viscosity [η] by the following formula.
Total number of terminal groups = 56.54 / [η] ^1.4338

8) Measurement of the number of white spots after high temperature and high humidity treatment;
In order to reproduce the increase in white spot when left in a harsh atmosphere for a long time, the disc is kept in a thermostatic chamber controlled at a temperature of 80 ° C. and a relative humidity of 85% for 1,000 hours, and then a polarizing microscope is used. The number of white spots of 20 μm or more was counted. This was performed for 25 optical disk substrates (diameter 120 mm), the average value was obtained, and this was taken as the number of white spots. If this was 1 piece / sheet or less, it was determined to be acceptable.

9) Strain point detection Strain point-1: Observe 25 disk substrates with a polarizing microscope, count the number of refractive index abnormal points,
This was taken as the strain point −1 and the average value per sheet was determined. If this was 1 piece / sheet or less, it was determined to be acceptable.
Strain point-2: Extruded sheet having a thickness of 2 mm and 50 cm × 50 cm, 10 sheets were observed with a polarizing microscope, the number of refractive index abnormal points was counted, and this was set as a strain point-2, and an average value per sheet was obtained. . If this was 3 pieces / sheet or less, it was determined to be acceptable.

10) Impact resistance Izod impact strength Evaluated by ASTM D-256 (notched).
After the polymer was dried at 120 ° C. under a high vacuum for 12 hours, an injection molded test piece of 3.2 mm was prepared with a mold and the Izod impact strength was measured.

11) Measurement of the number of luminescent materials;
1 kg of polycarbonate resin in a clean room of Class 1000 or higher is dissolved in 20 L of methylene chloride, filtered at room temperature and normal pressure with a 10 μm filter, the residue on the filter is dried, and the substance that emits light when irradiated with light having a wavelength of 380 nm The number was observed and measured with an optical microscope.

Examples of raw material purification 1) Bisphenol A:
Commercially available bisphenol A (hereinafter abbreviated as BPA) is dissolved in 5 times the amount of phenol, an adduct crystal of BPA and phenol is prepared at 40 ° C., and the resulting adduct crystal is 5.33 kPa (40 Torr) in BPA at 180 ° C. The phenol was removed until the phenol concentration of the solution was 3%, and then the phenol was removed by steam stripping. Next, the BPA was charged into a container equipped with a decompression device and a cooling device, and purified by sublimation at a pressure of 13.3 Pa (0.1 Torr) and a temperature of 139 ° C. in a nitrogen atmosphere. Sublimation purification was repeated twice to obtain purified BPA.

2) Diphenyl carbonate The raw material diphenyl carbonate (hereinafter abbreviated as DPC) is “plastic material course 17 polycarbonate author Toshihisa Tachikawa et al. (Nikkan Kogyo Shimbun). Then, distillation under reduced pressure was performed and a fraction of 167 to 168 ° C./2.000 kPa (15 mmHg) was collected, and further sublimation purification was performed in the same manner as above to obtain a DPC purified product.
The metal content in BPA and DPC prepared as described above is shown in Table 1 below.

Example 1 (Production of PC-1)
Manufacture of the polycarbonate concerning a fine crystalline particle was performed as follows. In a reaction vessel equipped with a stirrer, a rectifying column, and a decompressor, 137 parts by weight of the purified BPA and 135 parts by weight of purified DPC as raw materials, and disodium salt of bisphenol A as a polymerization catalyst 4.1 × 10 ⁻⁵ Part by weight and 5.5 × 10 ⁻³ parts by weight of tetramethylammonium hydroxide were charged and melted at 180 ° C. in a nitrogen atmosphere.
While stirring at a rotation speed of 40 rpm, the inside of the reaction vessel was depressurized to 13.3 kPa (100 mmHg), and the reaction was carried out for 20 minutes while distilling off the produced phenol.
Next, after raising the temperature to 200 ° C., the pressure was gradually reduced, and reaction was carried out at 4.0 kPa (30 mmHg) for 20 minutes while distilling off the phenol.
Further, the temperature was gradually raised and reacted at 220 ° C. for 20 minutes. At this point, the viscosity average molecular weight was 3,200 and Tc was 180 ° C.

Next, the reaction mixture was fed to a second polymerization tank heated to 240 ° C. with a polymerization tank heating jacket so that the temperature of the reaction mixture was not lower than Tc, and reacted at 4.0 kPa (30 mmHg) for 20 minutes. At this point, the viscosity average molecular weight was 4,800 and Tc was 233 ° C. Next, the temperature of the reaction mixture was rapidly raised to 250 ° C. and reacted for 20 minutes. At this point, the viscosity average molecular weight of the reaction mixture was 7,000 and Tc was 245 ° C.
Next, the stirring speed was changed to 30 rpm at 250 ° C., and the degree of vacuum was gradually increased, and the reaction was carried out at 250 ° C., the degree of vacuum, 2.67 kPa (20 mmHg) for 10 minutes, and 1.33 kPa (10 mmHg) for 5 minutes. In order to keep the temperature of the shearing portion between the stirring blade and the reaction vessel where the temperature rises most inside at 320 ° C. or less, the rotational speed when the viscosity average molecular weight becomes 8,000 from the relationship between the rotational power and the viscosity average molecular weight. Was reduced to 20 rpm.

Thereafter, the reaction temperature is further increased, the reaction is carried out at 260 ° C. for 20 minutes, the temperature is raised to 270 ° C., the degree of decompression is gradually increased, and finally the viscosity average molecular weight reaches 15,300 at 270 ° C./66.7 Pa (0.5 mmHg). The reaction was continued until
Thereafter, 3.6 × 10 ⁻⁴ parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate was added to each, and the mixture was stirred at 270 ° C./66.7 Pa (0.5 mmHg) for 10 minutes. Finally, the obtained polycarbonate has a viscosity average molecular weight of 15,300, a phenolic end group concentration of 85 (eq / ton-PC), a phenoxy end group concentration of 154 (eq / ton-PC), and a melt viscosity stability of 0%. Met. The content of fine crystalline particles was 0 / kg-PC.

Comparative Example 1 (Production of PC-2)
137 parts by weight of purified BPA and 135 parts by weight of purified DPC as raw materials and 4.1 × 10 ⁻⁵ parts by weight of disodium salt of bisphenol A as a polymerization catalyst in a reaction vessel equipped with a stirrer, a rectifying column, and a decompression device Then, 5.5 × 10 ⁻³ parts by weight of tetramethylammonium hydroxide was charged and melted at 180 ° C. in a nitrogen atmosphere.
While stirring at a rotational speed of 40 rpm, the inside of the reaction vessel was depressurized to 13.33 kPa (100 mmHg) and reacted for 20 minutes while distilling off the produced phenol. Next, after raising the temperature to 200 ° C., the pressure was gradually reduced, and reaction was carried out at 4.0 kPa (30 mmHg) for 20 minutes while distilling off the phenol.

Further, the temperature was gradually raised and reacted at 220 ° C. for 20 minutes. At this point, the viscosity average molecular weight was 3,200 and Tc was 180 ° C. Next, the reaction mixture was fed to the second polymerization tank heated to 230 ° C. with a polymerization tank heating jacket and reacted for 30 minutes. At this time, the viscosity average molecular weight was 4,800 and Tc was 233 ° C. During this time, it is estimated that a part of the polymerization tank stirring shaft became Tc or less. Subsequently, the temperature of the reaction mixture was gradually raised to 250 ° C. over 20 minutes, and further reacted at the same temperature and reduced pressure for 20 minutes. At this time, the viscosity average molecular weight was 7,000 and Tc was 245 ° C.
Subsequently, the rotational speed was changed to 30 rpm at 250 ° C., the degree of pressure reduction was gradually increased, and the reaction was continued for 10 minutes at 2.67 kPa (20 mmHg) and 5 minutes at 1.3 kPa (10 mmHg) to reach a viscosity average molecular weight of 8,000. At that time, the rotational speed was reduced to 20 rpm.

Thereafter, the reaction temperature is further raised, the reaction is carried out at 260 ° C. for 20 minutes, the temperature is raised to 270 ° C., the degree of vacuum is gradually increased, and finally the viscosity average molecular weight is 15 at 270 ° C./66.7 Pa (0.5 mmHg). The reaction was continued until 300.
Thereafter, 3.6 × 10 ⁻⁴ parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate was added to each, and the mixture was stirred at 270 ° C./66.7 Pa (0.5 mmHg) for 10 minutes. Finally, the viscosity average molecular weight was 15,300, the phenolic end group concentration was 87 (eq / ton-PC), the phenoxy end group concentration was 152 (eq / ton-PC), and the melt viscosity stability was 0%. The content of fine crystalline particles was 200 particles / kg-PC. The melting point of the fine crystalline particles was 320 ° C.

Example 2 and Comparative Example 2 (Production of PC-3 and PC-4)
In Example 1 and Comparative Example 1, respectively, 2.1 parts by weight of end-capping agent 2-methoxycarbonylphenylphenyl carbonate (SAM) was added when the polymerization was continued until the viscosity average molecular weight reached 22,500, 265 ° C., Stir at 133.3 Pa (1 mmHg) for 10 minutes, and then add 6.9 × 10 ⁻⁴ parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate as a melt viscosity stabilizer and add 265 ° C./66.7 Pa (0.5 mmHg). ) For 10 minutes.
Finally, viscosity average molecular weight 22,500, phenolic terminal OH concentration 30 (eq / ton-PC), 32 (eq / ton-PC), phenoxy terminal group concentration 120 (eq / ton-PC), 118 ( eq / ton-PC), and an aromatic polycarbonate having a melt viscosity stability of 0% was obtained (referred to as PC-3 and PC-4, respectively). The fine crystalline particle contents were 0 and 203 / kg-PC, respectively.
The physical properties of the aromatic polycarbonates obtained by the production methods of Examples 1 and 2 and Comparative Examples 1 and 2 are shown in Table 2 below.

Reference Example 1 and Reference Comparative Example 1
Tris (2,4-di-tert-butylphenyl) phosphite and 0.018% by weight of stearic acid monoglyceride were added to the aromatic polycarbonates of Example 1 and Comparative Example 1 above. Next, such a composition was melt-kneaded while venting at a cylinder temperature of 240 ° C. with a vented twin-screw extruder (KTX-46, manufactured by Kobe Steel) to obtain pellets. Using this pellet, a DVD (DVD-Video) disk substrate was formed, and a temperature and humidity deterioration test was performed.

Disc substrate molding DISK3 M III manufactured by Sumitomo Heavy Industries, Ltd. A special mold for DVD is mounted on an injection molding machine, and a nickel DVD stamper containing information such as address signals is attached to this mold, and the above pellets are automatically used. It is put into the hopper of the molding machine by conveyance, and the cylinder temperature is 380 ° C., the mold temperature is 115 ° C., the injection speed is 200 mm / sec, the holding pressure is 3,432 kPa (35 kgf / cm ² ), the diameter is 120 mm, the wall thickness is 0.6 mm. A DVD disc substrate was formed.
To test the reliability of optical discs under severe temperature and humidity conditions for a long time,
After holding the aromatic polycarbonate optical disk substrate at a temperature of 80 ° C. and a relative humidity of 85% for 1,000 hours, the substrate was evaluated by the following measurements.
For each, the number of strain points (in the case of a disk substrate; observed with a polarizing microscope, 25 disk substrates after molding, the number of refractive index abnormal points was counted, and the average value was obtained), the number of white spots ( The optical disk substrate after the temperature and humidity deterioration test was observed using a polarizing microscope, and the number of white spots of 20 μm or more was counted, and this was performed on 25 optical disk substrates (diameter 120 mm), and the average value was obtained. ) Values are shown in Table 3 below.

Reference Example 2 and Reference Comparative Example 2
After the aromatic polycarbonates of Example 2 and Comparative Example 2 were melted, they were quantitatively supplied by a gear pump and sent to a T die of a molding machine. 0.003 wt% of trisnonylphenyl phosphite was added from the front of the gear pump, and it was sandwiched between a mirror cooling roll and a mirror roll or melt-extruded into a sheet having a thickness of 2 mm or 0.2 mm and a width of 800 mm by one-side touch. For a sample with a thickness of 2 mm, the number of strain points −2 (obtained 2 mm thick, 50 cm × 50 cm polycarbonate sheet, 10 sheets were observed with a polarizing microscope, and the number of refractive index abnormal points was counted. The average value was obtained.) And the elongation at break was measured according to JIS, K6735. The results are shown in Table 4 below.

Reference example 3
A visible light curable plastic adhesive [Adel BENEFIX PC] was applied to one side of an aromatic polycarbonate sheet (thickness 2 mm) obtained from the polycarbonate of Example 2, and the same sheet was placed on one side so that no air bubbles would enter. After laminating while extruding, the adhesive strength of the laminate obtained by irradiating light of 5,000 mJ / cm ² with a photo-curing device equipped with a metal halide type dedicated to visible light was measured according to JIS K-6852 (compressive shear of adhesive). It was measured according to the adhesive strength test method). As a result, the adhesive strength was 10.4 MPa (106 kgf / cm ² ).

Reference example 4
To an aromatic polycarbonate sheet having a thickness of 0.2 mm obtained from the polycarbonate of Example 2, ink [Natsuda 70-9132: Color 136D smoke] and solvent [isophorone / cyclohexane / isobutanol = 40/40/20 (wt%) ] Were mixed to make it uniform, printed on a silk screen printer, and dried at 100 ° C. for 60 minutes. There was no transfer defect on the printed ink surface, and good printing was obtained.

Reference Example 5
30 parts of a polycarbonate resin (specific viscosity 0.895, Tg 175 ° C.) obtained by subjecting 1,1-bis (4-hydroxyphenyl) cyclohexane and phosgene to an ordinary interfacial polycondensation reaction, and Plast Red 8370 (Arimoto) as a dye A printing ink in which 15 parts by chemical industry) and 130 parts of dioxane as a solvent were mixed was obtained. A sheet (thickness 0.2 mm) obtained from the polycarbonate of Reference Example 2 printed with the printing ink was mounted in an injection mold, and polycarbonate resin pellets (Panlite L-1225, manufactured by Teijin Chemicals Ltd.) ) Was used for insert molding at a molding temperature of 310 ° C. There was no abnormality such as bleeding or blurring in the printed portion pattern of the molded product after the insert molding, and an insert molded product having a good printed portion appearance was obtained.

Reference Example 6
90 parts by weight of the polycarbonate of Example 2 and 10 parts by weight of Teijin Kasei Panlite L-1250 were melt kneaded while being devolatilized at a cylinder temperature of 240 ° C. by a vented twin screw extruder (Kobe Steel KTX-46). Got. Using the pellets, a sheet was prepared in the same manner as in Reference Example 2. Table 4 shows the physical properties of this sheet.

Example 3
The production of polycarbonate related to fine particles emitting light was performed as follows. 137 parts by weight of the purified BPA and 135 parts by weight of purified DPC as raw materials and 4.1 × 10 ⁻⁵ weight of disodium salt of bisphenol A as a polymerization catalyst in a reaction vessel equipped with a stirrer, a rectifying column, and a decompressor Parts, tetramethylammonium hydroxide 5.5 × 10 ⁻³ parts by weight, and melted at 180 ° C. in a nitrogen atmosphere.
While stirring at a rotational speed of 40 rpm, the inside of the reaction vessel was depressurized to 13.33 kPa (100 mmHg) and reacted for 20 minutes while distilling off the produced phenol. Next, after raising the temperature to 200 ° C., the pressure was gradually reduced, and reaction was carried out at 4.0 kPa (30 mmHg) for 20 minutes while distilling off the phenol.

Further, the temperature was gradually raised and reacted at 220 ° C. for 20 minutes. At this point, the viscosity average molecular weight was 3,200 and Tc was 180 ° C. Next, the polymerization tank heating jacket was fed to the second polymerization tank heated to 240 ° C. so that the temperature of the reaction mixture did not become Tc or lower, and reacted for 20 minutes. At this point, the viscosity average molecular weight was 4,800 and Tc was 233 ° C. Subsequently, the temperature of the reaction mixture was rapidly increased to 250 ° C. over 20 minutes so as not to exceed the set temperature. At this time, the viscosity average molecular weight was 7,000 and Tc was 245 ° C. Next, while stirring at a rotation speed of 30 rpm at 250 ° C., the reaction was continued gradually at a reduced pressure of 2.666 kPa (20 mmHg) for 10 minutes and at 1.333 kPa (10 mmHg) for 5 minutes, resulting in a viscosity average molecular weight of 8,000. At that time, the rotational speed was changed to 20 rpm so that the temperature of the shear heating unit in the reactor did not exceed 330 ° C., and finally the viscosity average molecular weight was 15 ° C. at 260 ° C./66.7 Pa (0.5 mmHg). The reaction was continued until 300.
Thereafter, 3.6 × 10 ⁻⁴ parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate was added to each, and the mixture was stirred at 260 ° C./66.7 Pa (0.5 mmHg) for 10 minutes. Finally, the viscosity average molecular weight was 15,300, the phenolic end group concentration was 85 (eq / ton-PC), the phenoxy end group concentration was 154 (eq / ton-PC), and the melt viscosity stability was 0%.

Comparative Example 3
Production of the aromatic polycarbonate was carried out as follows. 137 parts by weight of purified BPA and 135 parts by weight of purified DPC as raw materials and 4.1 × 10 ⁻⁵ parts by weight of disodium salt of bisphenol A as a polymerization catalyst in a reaction vessel equipped with a stirrer, a rectifying column, and a decompression device Then, 5.5 × 10 ⁻³ parts by weight of tetramethylammonium hydroxide was charged and melted at 180 ° C. in a nitrogen atmosphere.
While stirring at a rotation speed of 40 rpm, the inside of the reaction vessel was depressurized to 13.3 kPa (100 mmHg), and the reaction was carried out for 20 minutes while distilling off the produced phenol. Next, after raising the temperature to 200 ° C., the mixture was reacted at 4.0 kPa (30 mmHg) for 20 minutes while gradually reducing the pressure and distilling off phenol.

Further, the temperature was gradually raised, the reaction was carried out at 220 ° C. for 20 minutes, 240 ° C. for 20 minutes, and 260 ° C. for 20 minutes. Then, even at 270 ° C., the stirring speed was kept at 40 rpm and the pressure was gradually reduced to 2.666 kPa ( The reaction was continued for 10 minutes at 20 mmHg) and 5 minutes at 1.333 kPa (10 mmHg), and then the pressure was reduced to 66.7 Pa (0.5 mmHg). The temperature of the shearing part between the stirring blade and the reaction vessel may be 350 ° C., and the rotational speed remains at 40 rpm even when the viscosity average molecular weight reaches 10,000 due to the relationship between the rotational power and the viscosity average molecular weight. While stirring, the reaction was continued at a reduced pressure of 270 ° C./66.7 Pa (0.5 mmHg) until the viscosity average molecular weight reached 15,300.
Thereafter, 3.6 × 10 ⁻⁴ parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate was added to each, and the mixture was stirred at 270 ° C./66.7 Pa (0.5 mmHg) for 10 minutes. The finally obtained polycarbonate had a viscosity average molecular weight of 15,300, a phenolic end group concentration of 86 (eq / ton-PC), a phenoxy end group concentration of 153 (eq / ton-PC), and a melt viscosity stability of 0%. It was.

Example 4
In Example 3, when the rotational speed was changed to 260 rpm at 20 rpm, IRGANOX HP2215 / FF manufactured by Ciba Specialty Chemicals Co., Ltd .; 0.03 parts by weight (200 ppm) was added, and the mixture was gradually stirred. The reaction was continued at 260 ° C./66.7 Pa (0.5 mmHg) until the viscosity average molecular weight reached 15,300.
Thereafter, 3.6 × 10 ⁻⁴ parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate was added to each, and the mixture was stirred at 260 ° C./66.7 Pa (0.5 mmHg) for 10 minutes. Finally, the viscosity average molecular weight was 15,300, the phenolic end group concentration was 85 (eq / ton-PC), the phenoxy end group concentration was 154 (eq / ton-PC), and the melt viscosity stability was 0%.

Examples 5 to 6 and Comparative Example 4
In each of Examples 3 and 4 and Comparative Example 3, polymerization was continued until the viscosity average molecular weight reached 22,500, and at this time, 2.1 parts by weight of end-capping agent 2-methoxycarbonylphenylphenyl carbonate (SAM) was added. Stir at 265 ° C., 133.3 Pa (1 mmHg) for 10 minutes, and then add 6.9 × 10 ⁻⁴ parts by weight of tetrabutylphosphonium dodecylbenzenesulfonate as a melt viscosity stabilizer, 265 ° C./66.7 Pa ( The mixture was stirred for 10 minutes at 0.5 mmHg. Finally, the viscosity average molecular weight is 15,300, the phenolic end concentration is 30 (eq / ton-PC), 29 (eq / ton-PC), 31 (eq / ton-PC), respectively, and the phenoxy end group concentration is 120 each. (Eq / ton-PC), 121 (eq / ton-PC), 119 (eq / ton-PC) An aromatic polycarbonate having a melt viscosity stability of 0% was obtained.
When the X-ray diffraction pattern of the fine crystalline particles of the aromatic polycarbonate obtained in Examples 3 to 6 was measured, as shown in FIG. 1, the diffraction angle (2θ) showed a main peak at 17.180 °.
The physical properties of the aromatic polycarbonates obtained by the production methods of Examples 3 to 6, Comparative Example 3 and Comparative Example 4 are shown in Table 5 below.

Reference Examples 7 to 13 and Reference Comparative Examples 3 to 9
Trisnonylphenyl phosphite was added to the aromatic polycarbonate of Example 2 in an amount of 0.003% by weight and trimethyl phosphate to 0.05% by weight to obtain uniformly mixed aromatic polycarbonate pellets. After uniformly mixing these pellets and each component indicated by the following symbols described in Tables 6 and 7 using a tumbler, a 30 mmφ vented twin screw extruder (Kobe Steel Co., Ltd. KTX-30), The pellet was pelletized while being deaerated at a cylinder temperature of 260 ° C. and a vacuum of 1.33 kPa (10 mmHg), and the obtained pellet was dried at 120 ° C. for 5 hours, and then an injection molding machine (SG150U model manufactured by Sumitomo Heavy Industries, Ltd.) Were used to prepare molding pieces for measurement under conditions of a cylinder temperature of 270 ° C. and a mold temperature of 80 ° C., which were referred to as Reference Examples 7 to 13. The following evaluation was performed. The results are listed in Tables 6 and 7. Similarly, the same operation was performed using the aromatic polycarbonate of Comparative Example 2 to obtain Reference Comparative Examples 3 to 9.

(1) -1 ABS: Styrene-butadiene-acrylonitrile copolymer; Santac UT-61; manufactured by Mitsui Chemicals, Inc. (1) -2 AS: Styrene-acrylonitrile copolymer; Stylac-AS 767 R27; Asahi Kasei Kogyo (1) -3 PET: Polyethylene terephthalate; TR-8580; Teijin Limited, intrinsic viscosity 0.8
(1) -4 PBT: polybutylene terephthalate; TRB-H; manufactured by Teijin Limited, intrinsic viscosity 1.07
(2) -1 MBS: methyl (meth) acrylate-butadiene-styrene copolymer; Kane Ace B-56; manufactured by Kaneka Chemical Co., Ltd. (2) -2 E-1: butadiene-alkyl acrylate-alkyl methacrylate Copolymer; Paraloid EXL-2602; Kureha Chemical Industry Co., Ltd. (2) -3 E-2: Composite rubber in which polyorganosiloxane component and polyalkyl (meth) acrylate rubber component have an interpenetrating network structure Metabrene S-2001; Mitsubishi Rayon Co., Ltd. (3) -1 T: Talc; HS-T0.8; Hayashi Kasei Co., Ltd., average particle diameter L measured by laser diffraction method L = 5 μm, L / D = 8
(3) -2 G: glass fiber; chopped strand ECS-03T-511; manufactured by Nippon Electric Glass Co., Ltd., urethane bundling treatment, fiber diameter 13 μm
(3) -3 W: Wollastonite; Psycatech NN-4; manufactured by Sakai Kogyo Co., Ltd., number average average fiber diameter D determined by electron microscope observation = 1.5 μm, average fiber length 17 μm, aspect ratio L / D = 20
(4) WAX: Olefin-based wax by copolymerization of α-olefin and maleic anhydride; Diacarna-P30; manufactured by Mitsubishi Kasei Corporation (maleic anhydride content = 10 wt%)

(A) Flexural modulus The flexural modulus was measured according to ASTM D-790.
(B) Impact value with notch Using ASTM D-256, a test piece having a thickness of 3.2 mm was used to impact the weight from the notch side, and the impact value was measured.
(C) Fluidity Fluidity was measured by an Archimedean spiral flow (thickness 2 mm, width 8 mm) at a cylinder temperature of 250 ° C., a mold temperature of 80 ° C., and an injection pressure of 98.1 MPa.
(D) Chemical resistance 1% strain was added to the tensile test piece used in ASTM D-638, and the specimen was immersed in essoregular gasoline at 30 ° C. for 3 minutes, and then the tensile strength was measured to calculate the retention rate. The retention rate was calculated by the following formula.
Retention rate (%) = (strength of treated sample / strength of untreated sample) × 100

Claims (9)

Following formula (2)

(In the formula, R ¹ and R ² are each independently a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, or 6 to 20 carbon atoms. An aryl group of 7 to 20 carbon atoms, a cycloalkoxy group of 6 to 20 carbon atoms or an aryloxy group of 6 to 20 carbon atoms, m and n are each independently a number of 0 to 4, X is a single bond, oxygen atom, carbonyl group, alkylene group having 1 to 20 carbon atoms, alkylidene group having 2 to 20 carbon atoms, cycloalkylene group having 6 to 20 carbon atoms, cycloalkylidene group having 6 to 20 carbon atoms, carbon Represents an arylene group having 6 to 20 carbon atoms or an alkylene arylene alkylene group having 6 to 20 carbon atoms.)
An aromatic dihydroxy compound represented by:
Following formula (3)

(Here, Ar ¹ and Ar ² are each independently an optionally substituted aryl group having 6 to 10 carbon atoms, aralkyl group or alkyl group having 1 to 4 carbon atoms)
In the method of melt polycondensation with a carbonic acid diester represented by the following:
The viscosity average molecular weight Mn of the reaction mixture and the lowest temperature Tc (° C.) that is the temperature of the lowest temperature portion inside the polymerization apparatus defined by the viscosity average molecular weight Mn are Mn as the horizontal axis and Tc as the vertical axis. In coordinates, the points (Tc, Mn) = (220, 4,000), (234, 4, 810), (244, 6, 510), (245, 7, 400), (244, 9, 210), (236, 12,050), (226, 17,000) so as not to fall within a range surrounded by a curve that smoothly connects the points and two straight lines of Tc = 220 and Mn = 18,000, After melt polycondensation, (a) the main repeating unit is represented by the following formula (1)

(In the formula, the definitions of R ¹ , R ² , X, m and n are the same as in the above formula (2)).
Represented by
(C) the melt viscosity stability is 0.5% or less,
(D) the viscosity average molecular weight is 10,000 to 100,000;
(E) the terminal group substantially consists of an aryloxy group (A) and a phenolic OH group (B), the molar ratio (A) / (B) of both is 95/5 to 40/60, and (F) The content of fine crystalline particles collected in a filter having a nominal pore diameter of 3 μm and showing an X-ray diffraction pattern when a methylene chloride solution is obtained is 50 / kg polymer or less.
A process for producing an aromatic polycarbonate, comprising producing an aromatic polycarbonate.   As the aromatic dihydroxy compound and carbonic acid diester, those having a metal element content of 50 ppb or less are used. At the time of polymerization, the bulk temperature of the polycarbonate is 250 to 330 ° C., and the transesterification catalyst has lost its activity due to the melt viscosity stabilizer. The method for producing an aromatic polycarbonate according to claim 1, wherein in the step, the polycarbonate is not brought into contact with a high temperature metal surface of 350 ° C or higher.   The method for producing an aromatic polycarbonate according to claim 2, wherein the metal element is Na, Fe, Cr, Mn, Ni, Pb, Cu, Zn, Pd, In, Si, Al, or Ti.   The method for producing an aromatic polycarbonate according to claim 1, wherein the transesterification catalyst is a nitrogen-containing basic compound and / or a phosphorus-containing basic compound and an alkali metal compound.   The aromatic dihydroxy compound is bisphenol A, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl). ) -3-methylbutane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4- Hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2,2 ′, 2′-tetrahydro-3,3,3 ′, 3′-tetramethyl-1,1′-spirobis [1H-indene]- At least one bisphenol selected from the group consisting of 6,6′-diol and α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene The method for producing an aromatic polycarbonate according to claim 1.   The method for producing an aromatic polycarbonate according to claim 1, wherein a phosphonium salt of an organic sulfonic acid and / or an ammonium salt of an organic sulfonic acid is added as a melt viscosity stabilizer while the polycarbonate is in a molten state after polymerization.   The method for producing an aromatic polycarbonate according to claim 1, wherein the molar ratio of carbonic acid diester / aromatic dihydroxy compound at the time of charging the polymerization reaction is set between 1.03 and 1.10. As a transesterification catalyst, a nitrogen-containing basic compound and / or a phosphorus-containing basic compound is used in an amount of 1 × 10 ⁻⁵ to 1 × 10 ^{−3 with} respect to 1 mol of the aromatic nitrogenous compound or the basic phosphorus atom. The manufacturing method of Claim 4 used in the ratio used as a chemical equivalent. The manufacturing method of Claim 4 which uses an alkali metal compound as an alkali metal element in the range of 1 * 10 < ^-8 > -5 * 10 <^-6> chemical equivalent with respect to 1 mol of aromatic dihydroxy compounds as a transesterification catalyst.

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