JPH0733866A - Production of aromatic polycarbonate resin - Google Patents

Abstract

PURPOSE:To obtain the subject resin having excellent color tone and high quality in high productivity by the transesterification of an aromatic dihydroxy compound with a diaryl carbonate containing a specific amount of a benzophenone derivative. CONSTITUTION:This polycarbonate resin can be produced by the transesterification of (A) an aromatic dihydroxy compound of the formula I [R1 and R2 are H, halogen, alkyl, etc.; X is group of the formula II (R3 and R4 are H, 1-12C alkyl, etc.), etc.] [preferably bis(4-hydroxyphenyl)methane, etc.] with (B) a diaryl carbonate (preferably diphenyl carbonate) containing <=100ppm (preferably <=10ppm) of a benzophenone derivative (e.g. 2,2'- dihydroxybenzophenone). The amount of the component B is preferably 1-1.7mol (preferably 1.05-1.5mol) based on 1mol of the component A. The reaction is preferably carried out in the presence of an iminocarboxylic acid derivative as the catalyst using a reactor made of a metal or alloy having an iron content of >=25wt.%.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an aromatic polycarbonate resin known as engineering plastic. More specifically, the present invention relates to a method for producing a high-quality aromatic polycarbonate resin having an excellent color tone by a transesterification method (melting method).

[0002]

2. Description of the Related Art Aromatic polycarbonate resins have excellent impact resistance as engineering plastics,
Widely used for applications that take advantage of dimensional stability and transparency. As an industrial production method, an interfacial method in which a dihydroxydiaryl compound such as bisphenol is reacted with phosgene, or an ester exchange method in which a dihydroxydiaryl compound such as bisphenol and a carbonic acid diaryl ester such as diphenyl carbonate are reacted in a molten state (melting Law) is known.

[0003]

As a method for producing a carbonic acid diaryl ester such as diphenyl carbonate, a method of transesterifying a dialkyl carbonate in the presence of phenol has been extensively studied.
1-172852 describes that in these methods, by-product impurities having a boiling point close to that of the diaryl carbonate are mixed in the diaryl carbonate. Further, in JP-A-4-100824, when an aromatic polycarbonate is produced by a melting method, the xanthone content is 10 p
Methods using diaryl carbonates of pm or less are described. However, it has been difficult to say that these techniques are sufficiently established for coloring aromatic polycarbonate.

Further, regarding the coloring of the aromatic polycarbonate, the influence of the material of the reactor has been suggested. According to U.S. Pat. No. 4,383,092, it is proposed to prevent the aromatic polycarbonate from being colored by lining the liquid contact part of the reactor with glass or tantalum, nickel or chromium. On the other hand, JP-A-4-3
32726 describes that a material having an iron content of 20% or less is used for the liquid contact portion of the reactor. However, these metals are not practical because they are expensive to use as a reactor material.

[0005]

Means for Solving the Problems As a result of diligent studies for producing a high-quality aromatic polycarbonate resin having an excellent color tone with high productivity, the present inventors have found that when the aromatic polycarbonate is polymerized by the ester method. The inventors have found that the above problem can be solved by using a carbonic acid diaryl ester having a benzophenone derivative of 100 ppm or less, and have reached the present invention.

The present invention will be described in detail below. As the aromatic dihydroxy compound used as a raw material in the present invention, those represented by the general formula (I) are used.

[0007]

[Chemical 1]

In the general formula (I), R1 and R2 each independently represent a hydrogen atom, a halogen, an alkyl group, an alkenyl group or an optionally substituted aryl group, and X is

[0009]

[Chemical 2]

(However, R ³ and R ⁴ are each independently a hydrogen atom,
Alkyl groups having 1 to 12 carbon atoms or 6 to 1 carbon atoms
Represents an aryl group up to 2),

[0011]

[Chemical 3]

(Cycloalkylene group; n is an integer from 2 to 4), -O-, -CO-, -S-, -SO-, etc. Particularly preferred are bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) propane and 2,2-bis (4-hydroxy). Phenyl) propane, 1,1-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl)
Butane, 1,1-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) pentane, 3,3-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxy) Phenyl) -4-methylpentane, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (3-ethyl-
4-hydroxyphenyl) propane, 2,2-bis (3
-Isopropyl-4-hydroxyphenyl) propane,
2,2-bis (3-sec-butyl-4-hydroxyphenyl) propane, 2,2-bis (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) hexafluoropropane , Bis (4-
Hydroxyphenyl) phenylmethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane,
1,1-bis (4-hydroxyphenyl) -1-phenylpropane, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxyphenyl) dibenzylmethane, 1,1-bis (4-hydroxyphenyl) -cyclo Pentane, 1,1-bis (4-hydroxyphenyl) -cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfone , Phenolphthalein and the like. These aromatic dihydroxy compounds may be used alone or as a mixture.

The carbonic acid diaryl ester used in the present invention includes diphenyl carbonate, bis (p-chlorophenyl) carbonate, bis (o-chlorophenyl) carbonate, bis (2.4-dichlorophenyl) carbonate, bis (p-nitrophenyl) carbonate, Examples thereof include bis (o-nitrophenyl) carbonate, bisallyl carbonate of bisphenol A, and a polycarbonate oligomer having a phenyl carbonate group at the end. Diphenyl carbonate is preferred. Usually, these carbonic acid diesters are used in an amount of 1 to 1.7 mol, preferably 1.05 to 1.5 mol, per 1 mol of the aromatic dihydroxy compound.

The preferred amount of benzophenone derivative in the carbonic acid diaryl ester used in the present invention is 10
It is 0 ppm or less, more preferably 10 ppm or less. If the amount of benzophenone derivative is higher than this range,
The aromatic polycarbonate obtained after transesterification is colored yellow. As a benzophenone derivative that deteriorates the color tone of the aromatic polycarbonate shown in the present invention,
It is a compound represented by the general formula (II).

[0015]

[Chemical 4]

In the formula, R ^{5 to} R ¹⁴ are each independently a hydrogen atom,
Halogen, hydroxyl group, alkyl group, alkenyl group, optionally substituted aryl group, alkyloxy group, alkenyloxy group, optionally substituted phenyloxy group and the like are shown. Specific examples of the benzophenone derivative include benzophenone, 3-methylbenzophenone, 3-vinylbenzophenone, 2,4-dimethoxybenzophenone, 4,
4'-dimethoxybenzophenone, 2,2 ', 4,4'
-Tetrachlorobenzophenone, 2,3,4-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone and the like can be mentioned, but as those which further worsen the color tone of the aromatic polycarbonate, the above-mentioned benzophenone The derivative is mono- or dihydroxybenzophenone, 2-hydroxybenzophenone, 3-hydroxybenzophenone, 4-hydroxybenzophenone, 2-hydroxy-4-methoxyoxybenzophenone, 2,4-dihydroxybenzophenone, 2,4'-dihydroxybenzophenone, 4 , 4 '
-Dihydroxybenzophenone and the like. And especially those that deteriorate the color tone of aromatic polycarbonate are
It is 2,2'-dihydroxybenzophenone.

Note that 2,2'-dihydroxybenzophenone is a rearrangement product of diphenyl carbonate, and similarly rearrangement products such as salicylic acid phenyl ester and 4-hydroxybenzoic acid phenyl ester, dimers and trimers thereof. Etc. are also included in the category of the benzophenone derivative shown in the present invention. The method for producing a carbonic acid diaryl ester having a benzophenone derivative of 100 ppm or less used in the present invention is not particularly limited, and it is synthesized by a phosgene method or a transesterification method. The method for purifying the synthesized carbonic acid diaryl ester is not particularly limited, and the carbonic acid diaryl ester can be purified by the distillation method, sublimation method, recrystallization method, activated carbon method, or the like. preferable.

If desired, a mono-substituted phenol as a terminal blocking group may be added to the aromatic polycarbonate of the present invention. The monofunctional phenols used for such purposes include those represented by the general formula (III)

[0019]

[Chemical 5]

There is a compound represented by: Specific examples include cresol, methoxyphenol, tert-butylphenol, amylphenol, hexylphenol, octylphenol, cumylphenol and phenylphenol. These monofunctional phenols may be added at the beginning of the polymerization or after the transesterification reaction at the beginning of the polymerization is completed.

In the method for producing an aromatic polycarbonate resin of the present invention, a branched polycarbonate is prepared by adding a trivalent or higher polyfunctional compound such as phloroglucin or 1,1,1-tris (4-hydroxyphenyl) -ethane. It is also possible to Furthermore, terephthalic acid or dicarboxylic acid such as isophthalic acid may be added to obtain an aromatic polyester polycarbonate resin.

The transesterification catalyst which can be used in the present invention is
Specifically, in addition to alkali metal or alkaline earth metal phenolates, carbonates, acetates, hydroxides, hydrides, phosphorus compounds such as phenylphosphoric acid, phenylphosphorous acid and metal salts thereof, and tetramethylammonium. -Ammonium such as tetraphenylboranate, tetraphenylphosphonium-tetraphenylboranate, phosphonium borane salt catalyst, tetramethylammonium hydroxide, tetrabutylammonium hydroxide,
Ammonium hydroxides such as trimethylbenzylammonium hydroxide, quaternary ammonium salts such as dimethylphenylbenzylammonium chloride and benzyltributylammonium chloride, amines such as triethylamine, 2-methylimidazole and dimethyl-4-aminopyridine, or salts thereof, iminocarboxylic acids. Examples thereof include acid derivatives or salts thereof.

Of these, an iminocarboxylic acid derivative or a salt thereof is particularly preferable, and it may be used alone, or may be used in combination with the above-mentioned other catalysts. The iminocarboxylic acid derivative is a compound having a group represented by the general formula (IV) in the molecule.

[0024]

[Chemical 6]

(In the formula, n represents an integer of 1 to 3.) Specifically, iminodiacetic acid, iminodipropionic acid, N-methyliminodiacetic acid, iminodicarboxylic acid type compounds such as phenyliminodiacetic acid, and nitrilotriacone. Acetic acid, nitrilotricarboxylic acid type compounds such as nitrilotripropionic acid,
Ethylenediaminetetraacetic acid, ethylenediaminetetrapropionic acid, propylenediaminetetraacetic acid, cyclohexanediaminetetraacetic acid, xylylenediaminetetraacetic acid, diaminetetracarboxylic acid type compounds such as glycol ether diaminetetraacetic acid, diethylenetriaminepentaacetic acid, trimethylenetetraminehexaacetic acid, And so on.

As the metal salt of the above iminocarboxylic acid derivative, various metal salts can be used. For example, alkali metals such as lithium, sodium and potassium,
Alkaline earth metals such as beryllium, magnesium, calcium, barium, zinc, cadmium, copper, tin,
Examples thereof include metal salts of lead, manganese, cobalt, nickel and the like.

The amount of the iminocarboxylic acid derivative or its metal salt used is about 1 × 10 -6 to 1 mol%, preferably 1 × 10 -5, based on the total amount of the aromatic dihydroxy compound used as a raw material. It is about 1 × 10 −2 mol%. When the amount of the catalyst is too small, the polymerization rate becomes slow, which causes coloring. Further, even if it is used in an excessively large amount, it becomes a factor which adversely affects coloring, thermal stability, hydrolysis resistance and the like.

In the method for producing an aromatic polycarbonate resin of the present invention, it is possible to produce the polycarbonate resin in a single step using a tank reactor, but especially when producing a high molecular weight polycarbonate resin, It is preferable to synthesize a prepolymer having a low melt viscosity in the polycondensation step using a tank reactor, and to make the prepolymer have a high molecular weight in the postpolycondensation step. In the post-polycondensation step, a production method having a small heat history is preferable, and examples of such a production method include a method using a horizontal biaxial self-cleaning high viscosity reactor and a solid-state polymerization method. In particular, a method using a horizontal biaxial self-cleaning high viscosity reactor is preferable.

The reaction temperature in the prepolycondensation step is usually 1
The temperature is in the range of 40 ° C. to 320 ° C., and the pressure is in the range of normal pressure to 0.0001 Torr. In this step, a polycarbonate prepolymer having a viscosity average molecular weight of 5,000 to 20,000 is obtained. When the molecular weight of the prepolymer is lower than 5,000, it takes a long time to increase the molecular weight in the post-polycondensation step, which is disadvantageous in terms of productivity. When the molecular weight of the prepolymer exceeds 20,000, it is necessary to carry out at a high temperature of 330 ° C. or higher in order to prevent the melt viscosity from increasing during the production in the tank reactor, which is disadvantageous in terms of color tone. Become.

When the horizontal biaxial self-cleaning reactor is used in the post-polycondensation step to further increase the degree of polymerization, the prepolymer obtained in the first step may be directly fed in a molten state. The pelletized material may be melted again by an extruder or the like and then fed. Here, the horizontal type two-axis self-cleaning reaction apparatus used in the present invention is equipped with two horizontal rotary shafts that rotate in the same direction, and is attached to the horizontal rotary shaft so as to rotate together with the rotary shaft in the vertical direction. It has a stirring plate. Since the phases of the stirring plates are out of phase and rotate while keeping a slight gap between them, the resin attached to the stirring plates is stirred without staying and the surface is updated (self-cleaning property). The cross-sectional shape of the stirring plate is a disc type, a hollow disc type,
Examples thereof include a convex lens type, a rod type, a window frame type, and a pseudo-triangular type, but the present invention is not necessarily limited thereto.

The reaction temperature in the post-polycondensation step is
240 ° C to 350 ° C, preferably 250 ° C to 300 ° C
And the pressure is 10 Torr or less, preferably 2 Torr or less. Further, the horizontal reactor used in the present invention has a large internal volume of the apparatus as compared with a screw type twin-screw extruder, and the resin extrusion performance can be controlled by the shape and mounting position of the stirring plate. It is possible to take a long residence time. Usually a residence time of 1
It is 0 to 90 minutes, preferably 15 to 60 minutes. The viscosity average molecular weight of the aromatic polycarbonate obtained after the reaction using the horizontal reactor in the subsequent polycondensation step is 15,
000 to 60,000.

In the reactor, the material of the portion which comes into contact with the reaction mixture is a metal or an alloy having an iron content of 25% by weight or more, or a nickel and / or copper content of 70% by weight or more. Some are used. In addition, the aromatic polycarbonate resin obtained in the present invention may be added with a known heat stabilizer as needed to improve its heat stability. Examples of such heat stabilizers include phosphorus-based heat stabilizers such as phosphite triesters, benzenephosphonic acid, and acidic phosphoric acid esters, and antioxidants such as hindered phenols.

The aromatic polycarbonate resin obtained in the present invention may be modified with other resins, if necessary, and may be a filler such as glass fiber or carbon fiber, a flame retardant, a UV absorber, A release agent or a coloring agent may be added. The polycarbonate resin produced by the method of the present invention can produce a high-quality aromatic polycarbonate resin excellent in color tone without any problem due to residual methylene chloride. Therefore, the polycarbonate resin can be widely used as a general engineering plastic material such as a sheet or a lens, an optical component such as a compact disc or an optical disc, a transparent component such as an automobile, and a housing of various devices, and is industrially used. Is also extremely advantageous.

[0034]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. (1) Viscosity average molecular weight (Mv) Intrinsic viscosity [η] (dl
/ g) was measured using an Ubbelohde viscosity tube, and the viscosity average molecular weight was calculated using the following formula.

[0035]

[Equation 1] [η] = 1.23 × 10 ⁻⁴ (Mv) ^0.83 (2) Color tone of polymer The color tone of the pellet is a color computer (SM color computer manufactured by Suga Test Instruments Co., Ltd., model SM-).
Evaluation was made by the b value measured by the reflection method in 4). The larger the b value is, the higher the yellowness is, and as a sample having a good color tone, the b value is 1.5 or less, preferably the b value is 1.
It is 0 or less. (3) Content of 2,2'-dihydroxybenzophenone in diphenyl carbonate It was measured by a high performance liquid chromatography method.

Reference Example 80 kg of diphenyl carbonate was stirred and dissolved in a nitrogen stream at 100 ° C. for 1 hour and then heated to 140 ° C. Subsequently, the pressure was reduced to 3 Torr for distillation purification.
Purified diphenyl carbonate was obtained with a yield of 94%,
The content of 2,2'-dihydroxybenzophenone contained in this diphenyl carbonate was 10 ppm.

Example 1 4566 g (20.0 mol) of bisphenol A and 10 p of 2,2'-dihydroxybenzophenone obtained in Reference Example
4584 g of diphenyl carbonate containing pm (2
1.4 mol) and trilithium nitrilotriacetate (monohydrate)
0.022 g (0.001 mol) was charged into a 30-liter tank type reactor (SUS316L), the atmosphere was replaced with nitrogen, and then the temperature was gradually raised. Stirring was started after the reaction mixture was dissolved, and this time point was defined as the polymerization start time (internal temperature of 180 ° C). After that, the temperature was further raised to 270 ° C, the pressure was gradually reduced, the produced phenol was distilled off to continue the reaction, and finally the inside of the tank was kept at 1 Torr, and the polymerization was completed in 4 hours in total. After the pressure in the tank was restored, it was extruded in a strand shape into the water tank and pelletized with a cutter. The viscosity average molecular weight of the obtained polymer was 16,500. The polymer was colorless and transparent, and the color tone was 0.12.

Example 2 Polymerization was carried out in the same manner as in Example 1 except that diphenyl carbonate containing 60 ppm of 2,2'-dihydroxybenzophenone was used. The viscosity average molecular weight of the obtained polymer was 17,000. The polymer was colorless and transparent, and the color tone was 0.30 in b value.

Example 3 Polymerization was carried out in the same manner as in Example 1 except that diphenyl carbonate containing 90 ppm of 2,2'-dihydroxybenzophenone was used. The viscosity average molecular weight of the obtained polymer was 16,700. The polymer was colorless and transparent, and the color tone was 0.60 in b value.

Example 4 Polymerization was carried out in the same manner as in Example 1 except that 0.28 g (0.001 mol) of trisodium nitrilotriacetate (monohydrate) was used as a catalyst. The viscosity average molecular weight of the obtained polymer was 15,800. The polymer was colorless and transparent, and the color tone was 0.15 in b value.

Example 5 Polymerization was carried out in the same manner as in Example 1 except that 0.37 g (0.001 mol) of ethylenediaminetetraacetic acid disodium salt (dihydrate) was used as a catalyst. The viscosity average molecular weight of the obtained polymer was 15,700. The polymer was colorless and transparent, and had ab value of 0.20.

Example 6 Except that 0.46 g (0.005 mol) of tetramethylammonium hydroxide and 0.0008 (0.00002 mol) of sodium hydroxide were used as catalysts.
Polymerization was carried out in the same manner as in Example 1. The viscosity average molecular weight of the obtained polymer was 13,600. The polymer was colorless and transparent, and had ab value of 0.70.

Example 7 As a catalyst, 0.33 g of 2-methylimidazole (0.
Polymerization was performed in the same manner as in Example 1 except that (004 mol) was used. The viscosity average molecular weight of the obtained polymer is 1
It was 5,700. The polymer is colorless and transparent,
The b value was 0.90.

Example 8 Nickel 200 (Ni 99.5 wt%, C0.0
Polymerization was performed in the same manner as in Example 1 except that 5 wt%) was used. The viscosity average molecular weight of the obtained polymer was 15,
It was 500. The polymer was colorless and transparent, and had ab value of 0.10.

Example 9 4566 g (20.0 mol) of bisphenol A and 10 of 2,2'-dihydroxybenzophenone obtained in Reference Example were used.
4584 g of diphenyl carbonate containing ppm (2
1.4 mol) and trilithium nitrilotriacetate (monohydrate)
0.022 g (0.001 mol) was charged into a 30-liter tank type reactor (SUS316L), the atmosphere was replaced with nitrogen, and then the temperature was gradually raised. Stirring was started after the reaction mixture was dissolved, and this time point was defined as the polymerization start time (internal temperature of 180 ° C).
After that, the temperature was further raised to 270 ° C., the pressure was gradually reduced, the produced phenol was distilled off to continue the reaction, and finally the inside of the tank was kept at 1 Torr, and the polymerization was completed in a total polymerization time of 4 hours, After the pressure inside the tank was restored, it was extruded in a strand shape into the water tank and pelletized with a cutter.

Next, 0.03 parts by weight of diphenyl phosphonate was added as a heat stabilizer to 100 parts by weight of this prepolymer, and melted by a twin-screw extruder at 270 ° C. to obtain horizontal biaxial self-cleaning high viscosity. Reactor (internal volume 2 l
, Reaction temperature 270 ° C, vacuum degree 0.2 Torr, rotation speed 60
rpm) and extracted with a gear pump at 2.5 Kg / h. The residence time was 30 minutes. The viscosity average molecular weight of the obtained polymer was 27,800. The obtained polymer was colorless and transparent, and had ab value of 0.20.

Comparative Example 1 Example 1 except that diphenyl carbonate containing 200 ppm of 2,2'-dihydroxybenzophenone was used.
The reaction was carried out under the same conditions as above. The viscosity average molecular weight of the obtained polycarbonate was 16,800. The color tone was yellowish, and the b value was 6.20.

Comparative Example 2 0.18 g of calcium acetate (monohydrate) as a catalyst
The reaction was performed under the same conditions as in Example 1 except that (0.001 mol) was used. The viscosity average molecular weight of the obtained polycarbonate was 15,700. The color tone was yellowish and the b value was 2.20.

Comparative Example 3 The reaction was carried out under the same conditions as in Comparative Example 1 except that 0.28 g (0.001 mol) of trisodium nitrilotriacetate (monohydrate) was used as the catalyst. The viscosity average molecular weight of the obtained polycarbonate was 15,100. The color tone was yellowish, and the b value was 6.40.

[0050]

According to the method for producing an aromatic polycarbonate of the present invention, there is no problem due to residual methylene chloride,
Since a high quality aromatic polycarbonate resin excellent in color tone can be produced, it can be used in a wide range of applications.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hidekazu Shoji 1000, Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Sanryo Kasei Co., Ltd.

Claims (9)

[Claims] 1. A method for producing an aromatic polycarbonate resin by transesterification from an aromatic dihydroxy compound and a carbonic acid diaryl ester, wherein the carbonic acid diaryl ester having a benzophenone derivative of 100 ppm or less is used. Production method. 2. The method for producing an aromatic polycarbonate resin according to claim 1, wherein an iminocarboxylic acid derivative or a salt thereof is used as a catalyst. 3. The method for producing an aromatic polycarbonate resin according to claim 1, wherein the benzophenone derivative is mono- or dihydroxybenzophenone. 4. The method for producing an aromatic polycarbonate resin according to claim 1, wherein the benzophenone derivative is 2,2′-dihydroxybenzophenone. 5. The method for producing an aromatic polycarbonate resin according to claim 1, wherein the carbonic acid diaryl ester having a benzophenone derivative of 100 ppm or less is produced by a distillation purification method. 6. The transesterification reaction is carried out using a reactor in which the material of the portion in contact with the reaction mixture is a metal or alloy having an iron content of 25% by weight or more. 5. The method for producing an aromatic polycarbonate resin according to 5. 7. A transesterification reaction is carried out using a reactor in which the material of the portion which comes into contact with the reaction mixture is a metal or alloy having a nickel and / or copper content of 70% by weight or more. A method for producing the aromatic polycarbonate resin according to claim 1. 8. In producing an aromatic polycarbonate resin, a prepolymer having a viscosity average molecular weight of 5,000 to 20,000 is synthesized in a pre-polycondensation step using a tank reactor, and then in a post-polycondensation step. The method for producing an aromatic polycarbonate resin according to any one of claims 1 to 7, wherein the high molecular weight is obtained by a high viscosity reactor or solid phase polymerization. 9. The method for producing an aromatic polycarbonate resin according to claim 8, wherein a horizontal biaxial self-cleaning high viscosity reactor is used in the post-polycondensation step.