JP2000154244A - Polycarbonate resin and preparation thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polycarbonate resin which has a good hue, allows little generation of corrosive gas and is suitable for a wide range of usage such as food usage, optical usage, silicon wafers, electrical/electronic equipment containers, etc., and a preparation process thereof. SOLUTION: In a preparation process of a polycarbonate resin using phosgene as a starting material, phosgene having a carbon tetrachloride content of 100 ppm or smaller and a chlorine molecule content of 1,000 ppb or smaller, is used. Further, a polycarbonate resin prepared using phosgene as a starting material contains 10 ppm or less carbon tetrachloride and 100 ppb or less volatile chlorine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polycarbonate resin having a low content of carbon tetrachloride and a low content of volatile chlorine, and a polycarbonate resin which can be used in a wide range of applications. More specifically, carbon tetrachloride content 100p
pm or less, a method for producing a polycarbonate resin using phosgene having a chlorine molecule content of 1000 ppb or less, and a carbon tetrachloride content of 10 ppm or less and a volatile chlorine content of 1
The present invention relates to a polycarbonate resin having a good hue and little generation of a corrosive gas of 00 ppb or less.

[0002]

2. Description of the Related Art Conventionally, polycarbonate resins are excellent in various properties such as optical properties, mechanical properties, and electrical properties, and are therefore used in the fields of foods, optical fields such as multimedia recording media, silicon wafers and multimedia recording media. Are widely used in various fields such as storage container field, electric field and automobile field.

[0003] This polycarbonate resin is produced using phosgene as a raw material. Conventional phosgene generally has a carbon tetrachloride content of 150 to 200 ppm and a chlorine molecule content of 2000 to 10000 ppb.

A polycarbonate resin produced using such carbon tetrachloride and phosgene having a high chlorine molecule content contains a large amount of carbon tetrachloride and volatile chlorine, which deteriorates the color of the polymer and Hygiene, corrosion resistance of metal-deposited film, hydrolysis resistance, and the like are deteriorated, causing problems during use. Therefore, many methods for solving these problems have been proposed.

[0005] Japanese Patent Publication No. 6-76482 discloses a method for producing a polycarbonate resin with low mold corrosion by using phosgene having a reduced carbon tetrachloride content in phosgene by distillation. Further, Japanese Patent Application Laid-Open No. 10-2267
No. 24 discloses a polycarbonate resin having a good color tone in which volatile chlorine in phosgene is reduced by activated carbon treatment. Further, Japanese Patent Application Laid-Open No. Hei 10-212686 discloses a precision member storage container using a polycarbonate resin having a small amount of volatile chlorine and a good color tone.

[0006] However, it is recognized that each of the proposals has an effect only on one component of impurities in phosgene, but none of them has reached the level of satisfying a plurality of characteristics. Optical discs, especially digital versatile discs (DVD-ROM, DVD-video)
o, DVD-R, DVD-RAM, etc.) and high-density LSI
For applications such as a large-diameter 8-inch silicon wafer container used for such purposes as above, there is a demand for further improvement in the quality of the polycarbonate resin.

[0007]

The present inventors have noticed that the above-mentioned problems cannot be solved even if phosgene is simply distilled or treated with activated carbon and reduced with only carbon tetrachloride or volatile chlorine alone. After careful examination, surprisingly,
The carbon tetrachloride and chlorine molecules contained in phosgene contained two impurities, carbon tetrachloride content of 100 ppm or less, and chlorine molecule content of 1000 ppb or less to produce a polycarbonate resin. A polycarbonate resin having a chlorine content of 100 ppb or less can be obtained. Surprisingly, the polycarbonate resin has excellent hue and can generate very little corrosive gas. Silicon wafer and electricity
The present inventors have determined that the present invention can be preferably applied to a wide range of uses such as electronic equipment storage containers, and have completed the present invention.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a carbon tetrachloride content of 100 ppm or less and a chlorine molecule content of 1 ppm.
An object of the present invention is to provide a method for producing a polycarbonate resin using phosgene of 000 ppb or less and a polycarbonate resin containing 10 ppm or less of carbon tetrachloride and 100 ppb or less of volatile chlorine and low in corrosive gas.

That is, the present invention provides a method for producing a polycarbonate resin using phosgene as a raw material, wherein the content of carbon tetrachloride is 100 ppm or less and the content of chlorine molecule is 1 ppm.
A method for producing a polycarbonate resin using phosgene of 000 ppb or less, and a polycarbonate resin produced using phosgene as a raw material, wherein carbon tetrachloride is 10 ppm or less and volatile chlorine is 100 pp
This is achieved by a polycarbonate resin having a low content of corrosive gas, which is characterized by containing b or less.

Hereinafter, the present invention will be described in more detail. As an example of the method for producing the polycarbonate resin of the present invention, phosgene is produced by reacting carbon monoxide (hereinafter abbreviated as CO) with chlorine (hereinafter abbreviated as Cl2) using an activated carbon catalyst. This is a method for producing a polycarbonate resin by a known interfacial polycondensation method using phosgene as a raw material.

The phosgene used in the present invention has a carbon tetrachloride content of 100 ppm or less, preferably 50 ppm or less. Further, the chlorine molecule content is 1000 ppb or less, preferably 100 ppb or less, more preferably 50 ppb or less, and particularly preferably 5 ppb or less.

Carbon tetrachloride content in phosgene 100 pp
m or more and the chlorine molecule content is 1000 ppb or more, when the carbon tetrachloride content is 10 ppm or less and the volatile chlorine content is 100 ppb or less, and the polycarbonate resin with less volatile chlorine cannot be obtained,
A polycarbonate resin applicable to a wide range of applications aimed at by the present invention cannot be obtained.

The carbon tetrachloride content used in the present invention is 100 p
The phosgene having a pm or less and a chlorine molecule content of 1000 ppb or less can be obtained by performing a phosgenation reaction between CO and Cl2 in a multistage reaction tank having two or more stages. This multi-stage reaction tank is preferably 2 to 10 stages, more preferably 2 to 6 stages, and 3 to 10 stages.
~ 4 stages are most preferred. As an example of the four stages, a first reaction vessel in which an apparatus having a function for removing reaction heat is filled with activated carbon in which the total specific surface area of activated carbon is 20 to 40% of the total specific surface area of the fourth reaction vessel, A second reaction tank filled with an apparatus having a function for removing reaction heat, wherein the total specific surface area of the activated carbon is 40-60% of the total specific surface area of the fourth reaction tank;
A device having a function for removing the heat of reaction has a total specific surface area of activated carbon of 70 to 80% of the total specific surface area of the fourth reaction tank.
And a fourth reaction tank filled only with activated carbon is connected in series to an apparatus having a function for removing reaction heat. In order to further reduce the chlorine molecule content, it is preferable to provide a tank filled with metal antimony, which has a function of removing reaction heat after the fourth reaction tank. After the metal antimony-filled tank, a condenser through which brine at -20 ° C. is passed generally and a liquefied phosgene storage tank provided with a weighing device are provided. It is obtained by connecting these devices in series and passing CO and Cl2 gas from the first reaction tank so that the molar ratio with CO (the molar ratio of CO / Cl2) becomes 1.015 or more. As a method of further reducing the amount of generated carbon tetrachloride, the amount of heat generated in the tank may be reduced by reducing the ventilation of CO and Cl2 gas. In order to further reduce the amount, there is a method in which phosgene is separated by distillation. However, the method of separating by distillation has almost no effect of lowering the chlorine molecule content. Also, the higher the molar ratio of CO / Cl2, the lower the amount of metal antimony and the lower the chlorine molecule content. However, if the molar ratio of CO / Cl2 is too high, the yield decreases. 1.
The range of 015 to 1.060 is preferable, and 1.020 to
A range of 1.045 is more preferred.

When the molar ratio of CO / Cl2 is 1.015-1.
When it is in the range of 060, the chlorine molecule content in phosgene is small, the hue of the polycarbonate resin is improved, and the generation of volatile gas is reduced.

The total specific surface area of the activated carbon in the reaction tank can be adjusted by, for example, a method of changing the mixing ratio of the activated carbon to a ceramic or glass bead, a Raschig ring, or a method using activated carbon having a different specific surface area.

The above-mentioned method for producing phosgene is listed as an example, and phosgene produced by any method can be preferably used as long as it meets the conditions of the present invention.

The polycarbonate resin targeted in the present invention is usually obtained by reacting a dihydric phenol with a carbonate precursor by a solution method. Representative examples of the dihydric phenol used here include hydroquinone,
Resorcinol, 4,4'-dihydroxydiphenyl,
Bis (4-hydroxyphenyl) methane, bis {(4-
(Hydroxy-3,5-dimethyl) phenyl} methane,
1,1-bis (4-hydroxyphenyl) ethane, 1,
1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane (commonly known as bisphenol A), 2,2-bis {(4-hydroxy-3-methyl) phenyl} Propane, 2,2-
Bis {(4-hydroxy-3,5-dimethyl) phenyl} propane, 2,2-bis} (3,5-dibromo-4
-Hydroxy) phenyl {propane, 2,2-bis {(3-isopropyl-4-hydroxy) phenyl} propane, 2,2-bis {(4-hydroxy-3-phenyl) phenyl} 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) -4-isopropylcyclohexane, 1,1 -Bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis {(4-hydroxy-3
-Methyl) phenyl} 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'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfide,
4,4'-dihydroxydiphenyl ketone, 4,4'-
Examples thereof include dihydroxydiphenyl ether and 4,4′-dihydroxydiphenyl ester, and these can be used alone or as a mixture of two or more.

Bisphenol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} 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 and α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene at least one dihydric phenol selected from the group consisting of A copolymer or a copolymer is preferable, and particularly, a homopolymer 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.

As the carbonate precursor, carbonyl halide, carbonate ester, haloformate and the like are used, and specific examples include phosgene, diphenyl carbonate and dihaloformate of dihydric phenol.

In producing the polycarbonate resin by reacting the above-mentioned dihydric phenol with the carbonate precursor by a solution method, a catalyst, a terminal stopper, an antioxidant for the dihydric phenol and the like may be used as necessary. Is also good. Further, even if the polycarbonate resin is a branched polycarbonate resin obtained by copolymerizing a trifunctional or higher polyfunctional aromatic compound,
A polyester carbonate resin obtained by copolymerizing an aromatic or aliphatic bifunctional carboxylic acid may be used,
It may be a mixture of two or more of the obtained polycarbonate resins.

The reaction by the solution method is usually a reaction between dihydric phenol and phosgene, and is carried out in the presence of an acid binder and an organic solvent. As the acid binder, for example, an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide or an amine compound such as pyridine is used. As the organic solvent, for example, halogenated hydrocarbons such as methylene chloride and chlorobenzene are used. Further, for promoting the reaction, for example, a catalyst such as a tertiary amine such as triethylamine, tetra-n-butylammonium bromide, or tetra-n-butylphosphonium bromide, a quaternary ammonium compound, or a quaternary phosphonium compound may be used. it can. At that time, the reaction temperature is usually 0 to 40 ° C., the reaction time is preferably about 10 minutes to 5 hours, and the pH during the reaction is preferably maintained at 9 or more.

In such a polymerization reaction, a terminal stopper is usually used. Monofunctional phenols can be used as such a terminal stopper. Monofunctional phenols are commonly used as molecular terminators for molecular weight control, and the resulting polycarbonate resins are capped by groups based on monofunctional phenols, so that Excellent heat stability. Such a monofunctional phenol is generally a phenol or a lower alkyl-substituted phenol, and may be a monofunctional phenol represented by the following general formula (1).

[0023]

Embedded image

Wherein A is a hydrogen atom, a linear or branched alkyl group having 1 to 9 carbon atoms or a phenyl-substituted alkyl group, and r is an integer of 1 to 5, preferably 1 to 3. . ]

Specific examples of the above monofunctional phenols include phenol compounds having one hydroxyl group such as phenol, p-tert-butylphenol, p-cumylphenol and isooctylphenol.

Other monofunctional phenols include:
Phenols or benzoic acid chlorides having a long-chain alkyl group or an aliphatic polyester group as a substituent, or long-chain alkyl carboxylic acid chlorides can be used. When blocked, these not only function as a terminal terminator or a molecular weight regulator, but also improve the melt flowability of the resin, not only facilitate the molding process, but also reduce the physical properties as a substrate, especially the water absorption of the resin. And the effect of reducing the birefringence of the substrate is preferably used. Among them, phenols having a long-chain alkyl group represented by the following general formulas (2) and (3) as a substituent are preferably used.

[0027]

Embedded image

[0028]

Embedded image

Wherein X is -RO-, -R-CO-O
— Or —RO—CO—, wherein R represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 10, preferably 1 to 5 carbon atoms, and n represents an integer of 10 to 50. Show. ]

As the substituted phenols of the formula (2), those wherein n is 10 to 30, especially 10 to 26 are preferred.
Specific examples thereof include decylphenol, dodecylphenol, tetradecylphenol, hexadecylphenol, octadecylphenol, eicosylphenol, docosylphenol, and tricontylphenol.

The polycarbonate solution thus obtained by the polycondensation reaction is obtained by washing the organic phase until the electrolyte is eliminated, and finally removing the solvent from the organic phase to obtain solids such as granules and flakes. The solid matter is dried to obtain a polycarbonate resin. Generally, the dried solid matter is melt-extruded, and a pelletized product is preferably used for molding.

The viscosity average molecular weight of the polycarbonate resin used for molding is about 10,000 to 100,000, preferably about 11,000 to 45,000. The molecular weight of the polycarbonate resin for an optical disk is
The viscosity average molecular weight is preferably 10,000 to 22,000, more preferably 12,000 to 20,000, and
000 to 18,000 is particularly preferred. A polycarbonate resin having such a viscosity average molecular weight is preferable because sufficient strength is obtained as an optical material, and the melt fluidity during molding is good, and molding distortion is not generated.

The molecular weight of the polycarbonate resin used for the container for precision equipment such as a silicon wafer is preferably 14,000 to 30,000 in terms of viscosity average molecular weight.
4,500-25,000 is more preferable, and 15,000
0 to 24,000 is more preferred. An aromatic polycarbonate resin having such a viscosity average molecular weight is preferable because it has a certain mechanical strength and good fluidity during molding.

The above polycarbonate resin is used by appropriately adding a modifying agent such as a release agent, an antistatic agent, a whitening agent, a heat stabilizer, an antioxidant, an ultraviolet absorber (weathering agent), and an antibacterial agent. Can be.

The polycarbonate resin which can be used for various purposes has a carbon tetrachloride content of 10 ppm or less and a volatile chlorine content of 100 ppb or less.
ppm or less and a volatile chlorine content of 5 ppb or less are more preferred, and a carbon tetrachloride content of 500 ppb or less and a volatile chlorine content of 5 ppb or less are more preferred.

If the carbon tetrachloride content exceeds 10 ppm or the volatile chlorine content exceeds 100 ppb, the hue of the polycarbonate resin deteriorates, and carbon tetrachloride and volatile chlorine are generated during use. Corrodes metals. In addition, since it promotes hydrolysis of the resin, it is difficult to apply it to various uses such as food applications, optical applications, silicon wafers, and containers for electric / electronic devices.
Therefore, it is preferable to reduce the content of carbon tetrachloride and the content of volatile chlorine in the polycarbonate resin.

Since these polycarbonate resins generate little carbon tetrachloride and volatile chlorine, molded products molded by an extruder, an injection molding machine or the like can be used in various fields, for example,
It is very preferably used in a wide range of applications such as food applications, optical applications, silicon wafers, and containers for electric and electronic equipment.

[0038]

The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples unless it exceeds the gist. In the examples, "part"
"A" means "parts by weight", and various evaluations and molded plates for evaluation were performed by the following methods.

1) Measurement of carbon tetrachloride content in phosgene 1 μl of the obtained liquefied phosgene was injected into a gas chromatograph equipped with an electron capture detector (type 263, manufactured by Hitachi, Ltd.) and measured.

2) Measurement of chlorine molecule content in phosgene 100 g of the obtained liquefied phosgene was sampled, and this was vaporized, absorbed in a NaOH solution, and extracted with NaCl.
Redox titration was performed as O, and the absolute amount was measured to determine the content of chlorine molecules in phosgene.

3) Viscosity-average molecular weight of polycarbonate resin 0.7 g of polycarbonate resin was dissolved at 20 ° C. in 100 ml of methylene chloride. The specific viscosity (ηsp) obtained from this solution was obtained by inserting it into the following equation. ηsp / c = [η] + 0.45 × [η] ² c (where [η]
Is the intrinsic viscosity) [η] = 1.23 × 10 ⁻⁴ M ^0.83 c = 0.7

4) Measurement of Carbon Tetrachloride Content in Polycarbonate Resin 5 g of the obtained pellet was placed in a 120 ml stainless steel container, sealed and heated at 250 ° C. for 2 hours. It was injected into a gas chromatograph with a detector (type 263, manufactured by Hitachi, Ltd.) and measured.

5) Measurement of Volatile Chlorine Content in Polycarbonate Resin 10 g of the obtained pellet was put into a glass tube having an inner diameter of 10 mm, which was washed with water for ion chromatography, and sealed under vacuum. And then cooled at room temperature for 3 days in an oil bath. The sealed portion of the cooled glass tube was cut, the inside of the glass tube was washed with 1 ml of water for ion chromatography, and the washed water was analyzed by ion chromatography to determine the volatile chlorine content per 1 g of the polymer.

6) Preparation of Molded Plate for YI Value Injection molding machine (Nippon Steel Works Co., Ltd .: Nikko Anchor V-
17-65 type), and plasticized at 340 ° C. at a cylinder temperature, and then a 2 mm thick 500 mm plate was formed.

7) Measurement of YI value The molded plate for YI value was measured with a color difference meter (Z-10 manufactured by Nippon Denshoku Co., Ltd.).
X.01DP). Y. AST from Z
Based on M-E1925, it was calculated using the following equation. YI = [100 (1.28X-1.06Z)] / Y

8) Measurement of BLER The obtained pellet was injected into an injection molding machine [DI manufactured by Sumitomo Heavy Industries, Ltd.
SK3M III] 1.2mm thick, 120mmφ A
The substrate was held in a thermo-hygrostat controlled at a temperature of 80 ° C. and a relative humidity of 85% for 1000 hours, and the BLER was measured with a BLER measuring device (manufactured by Sony, CDp).
layer control unit CDS-3
000). C1AVE shown in Table 1 is C
This is the average value (number) of one error (random error that can be corrected by the C1 code) per second, and the smaller the value, the better. In addition, C1AVE before processing was all in the range of 0.0 to 1.0.

9) Preparation of molded plate (disk) for evaluation of white spots after wet heat treatment A DVD-video disk substrate (diameter 120 mm, thickness: 120 mm, thickness: DISK3M III manufactured by Sumitomo Heavy Industries, Ltd.) using pellets. 0.6 mm).

10) Measurement of the number of white spots after wet heat treatment In order to reproduce the increase in the number of white spots when left in a severe atmosphere for a long time, the white spot evaluation disk was controlled at a temperature of 80 ° C. and a relative humidity of 85%. 1000 hours in a constant temperature and humidity chamber
Thereafter, the number of white spots of 20 μm or more was counted using a polarizing microscope. This is put on 25 optical disc substrates (diameter 120
mm), the average value was obtained, and this was defined as the number of white spots. The smaller the number of white spots, the better.

11) Measurement of Contact Angle The obtained pellets are formed into a semiconductor wafer storage / transport container using an injection molding machine, and a semiconductor 8-inch wafer 5 is placed in the container.
After inserting the wafers and keeping them at room temperature in a closed container for one week, the semiconductor wafer was taken out, and the contact angle between water on five surfaces and the wafer surface was measured for each semiconductor wafer, and the average value was shown. The contact angles before the treatment were all 3.5 to 4.
The range was 0 °. As the contact angle increases, the defect rate of the semiconductor increases.

Comparative Example 1 (A) Cold water at 10 ° C. was passed through the shell side of a multitubular reaction vessel having a function of removing reaction heat, and activated carbon 5 was passed through the tube side.
After the reaction tank filled with 0 kg, a condenser through which brine of -25 ° C. was passed and a liquefied phosgene storage tank provided with a weighing device were provided. These devices were connected in series, and the CO / Cl 2 molar ratio was determined from the reaction tank. C to be 1.018
O 10.18 Nm ³ / Hr and Cl ² gas 10.00 Nm ³
/ Hr was aerated to obtain 100 kg of liquefied phosgene. The phosgene had a carbon tetrachloride content of 150 ppm and a chlorine molecule content of 5000 ppb.

(B) A reactor equipped with a thermometer, a stirrer and a reflux condenser was charged with 219.4 parts of ion-exchanged water and 40.2 parts of a 48% aqueous sodium hydroxide solution. 57.5 parts of (hydroxyphenyl) propane (0.
252 mol) and 0.12 parts of hydrosulfite, and 181 parts of methylene chloride were added.
At ２５25 ° C., 28.3 parts of the above phosgene were blown in over 40 minutes. After completion of the phosgene blowing, 7.2 parts of a 48% aqueous sodium hydroxide solution and 2.42 parts of p-tert-butylphenol were added, stirring was started. After emulsification, 0.06 part of triethylamine was added, and the mixture was further heated at 28 to 33 ° C. for 1 hour. The reaction was completed by stirring. After the completion of the reaction, the product was diluted with methylene chloride, washed with water, acidified with hydrochloric acid, and washed with water.When the conductivity of the aqueous phase became almost the same as that of ion-exchanged water, an isolation chamber having a foreign substance take-out port in the bearing was formed. The methylene chloride was evaporated using a kneader provided, and the viscosity average molecular weight was 15,10.
No. 0 polycarbonate resin powder was obtained. The powder was dried at 145 ° C. for 6 hours and tris (2,4-di-t)
tert-butylphenyl) phosphite was added in an amount of 0.004% by weight and stearic acid monoglyceride in an amount of 0.06% by weight. Next, the powder was subjected to a cylinder temperature of 2 using a vent type twin screw extruder [KTX-46 manufactured by Kobe Steel Ltd.].
The mixture was melt-kneaded at 40 ° C. with a vent gas suction of −5 mmHg to obtain pellets. Evaluation was performed using the pellets. Table 1 shows the results.

Comparative Example 2 Pellets were obtained in the same manner as in Comparative Example 1, except that the liquefied phosgene (A) in Comparative Example 1 was subjected to simple distillation. Table 1 shows the results.

Comparative Example 3 The same procedure as in Comparative Example 1 was conducted except that the liquefied phosgene (A) obtained in Comparative Example 1 was passed through a tank filled with activated carbon. Table 1 shows the results.

[Comparative Examples 4 to 6] In the step of producing the polycarbonate resin (B) of Comparative Examples 1 to 3, p-te
The procedure was performed in the same manner as in Comparative Examples 1 to 3, except that 1.55 parts of rt-butylphenol was used. Table 2 shows the results.

Example 1 (A) Cold water of 10 ° C. was passed through the shell side of a multitubular reactor having a function of removing reaction heat, and activated carbon 1 was passed through the tube side.
1st filled with a mixture of 5kg and 3mm diameter glass ball
The second reaction tank filled with a mixture of 25 kg of activated carbon and a glass ball having a diameter of 3 mm on the tube side by passing cold water of 10 ° C. through the shell side of the reaction vessel and the shell-and-tube reactor, and the shell side of the shell-and-tube reactor Through the cold water of 10 ° C.
A third reaction vessel filled with a mixture of 7.5 kg and a glass ball having a diameter of 3 mm, a fourth reaction vessel in which cold water at 10 ° C. was passed through the shell side of the multitubular reaction vessel, and a tube side filled with 50 kg of activated carbon ( After the fourth reaction tank, a tank filled with metal antimony having an internal cooling tube was provided after the fourth reaction tank, and after the metal antimony filling tank, a condenser through which brine of -25 ° C. was passed and a weighing device were attached. Liquefied phosgene storage tank is provided, these devices are connected in series, and from the first reaction tank,
CO1 so that the molar ratio of CO / Cl2 is 1.040.
0.40 Nm ³ / Hr and Cl ² gas 10.00 Nm ³ / H
r was passed to obtain 100 kg of liquefied phosgene. The content of carbon tetrachloride in the phosgene was 35 ppm, and no chlorine molecule was detected.

(B) A pellet was obtained in the same manner as in Comparative Example 1 except that this liquefied phosgene was used. Evaluation was performed using the pellets. Table 1 shows the results.

[Example 2] In the production of phosgene, the method was changed to the method in which CO and Cl2 gas were introduced from the second reaction tank, and (A) liquefied phosgene was obtained. . Table 1 shows the results.

Example 3 In the production of phosgene, the method was changed to a method in which the metal antimony filled tank was not ventilated.
(A) The same procedure as in Example 1 was performed except that liquefied phosgene was obtained. Table 1 shows the results.

Example 4 The phosgene liquefied phosgene of Example 1 was prepared by using a distillation column (theoretical plate number: 6) packed with a sulzer packing manufactured by Sumitomo Heavy Industries, Ltd., with a reflux ratio of 0.4 and a phosgene feed. The procedure was carried out in the same manner as in Example 1 except that the rectification was carried out at a temperature of 31.0 ° C. and a top temperature of 27.0 ° C. Table 1 shows the results.

Example 5 The procedure of Example 1 was repeated, except that the production of the polycarbonate resin (B) was changed to 1.55 parts of p-tert-butylphenol. Table 2 shows the results.

Example 6 Production of phosgene was carried out in the same manner as in Example 5, except that CO and Cl2 gas were introduced from the second reactor and the method was not changed to a method in which the metal antimony-filled tank was not ventilated. Table 2 shows the results.

[0062]

[Table 1]

[0063]

[Table 2]

[0064]

The polycarbonate resin is produced using phosgene having a carbon tetrachloride content of 100 ppm or less and a chlorine molecule content of 1000 ppb or less, and a polycarbonate resin having a carbon tetrachloride content of 10 ppm or less and a chlorine molecule content of 5 ppb or less. The polycarbonate resin has low corrosive gas, and has excellent properties such as hygiene and hue, so that it can be widely applied to optical applications, food applications, optical and precision equipment storage containers, and automobile applications. In particular, optical disks for recording / reproducing information by irradiating laser light, that is, optical disk substrates such as magneto-optical disks, various write-once disks, digital audio disks (so-called compact disks), and optical video disks (so-called laser disks). Among them, digital versatile discs (DVD-ROM, DVD-v
It is more suitable as a material for a substrate for an optical disk having a higher density than a CD represented by, for example, video, DVD-R, and DVD-RAM. It is also suitable for a container for precision equipment such as silicon wafers and electric / electronic devices, particularly for a container for silicon wafers.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shigekazu Nakano 1-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo F-term in Teijin Chemicals Limited (reference) 4J029 AA08 AA10 AB05 AC01 AD10 AE05 AE18 BB05A BB10A BB12A BB12B BB12C BB13A BB13B BB13C BD09A BD09B BD09C BE05A BE07 BF14A BG08X BH02 DB10 DB13 FA07 FB15 HC01 HC02 HC03 JC031 JC091 JC631 KA01 KA03 KD01 KE05 KE09 KH05

Claims (2)

[Claims] 1. A method for producing a polycarbonate resin using phosgene as a raw material, wherein the content of carbon tetrachloride is 1
A method for producing a polycarbonate resin, wherein phosgene having a content of not more than 00 ppm and a chlorine content of not more than 1000 ppb is used. 2. A polycarbonate resin containing less than 10 ppm of carbon tetrachloride and 100 ppb or less of volatile chlorine in a polycarbonate resin produced using phosgene as a raw material.