JP2011219636A - Method for producing polycarbonate resin, and polycarbonate resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a polycarbonate resin excellent in hue or heat stability.SOLUTION: In this method for producing a polycarbonate resin from a dihydroxy compound containing a compound shown by formula (1) as a main component, the content rate of a compound shown by formula (2) is below 100 ppm. (In the formula (1), Rand Rshow each independently a substituted or unsubstituted 1-20 C alkyl group or a substituted or unsubstituted aryl group, and X shows a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom). (In the formula (2), R, Rand Rshow each independently a substituted or unsubstituted 1-20C alkyl group or a substituted or unsubstituted aryl group, and Rshows a hydrogen atom, a substituted or unsubstituted 1-20C alkyl group or a substituted or unsubstituted aryl group, and X shows a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom).

Description

  The present invention relates to a method for producing a polycarbonate resin. More specifically, the present invention relates to a method for producing a polycarbonate resin excellent in hue and thermal stability and a polycarbonate resin obtained by the method.

  Polycarbonate resins are excellent in mechanical strength, electrical characteristics, transparency and the like, and are widely used as engineering plastics in various fields such as electrical / electronic equipment field and automobile field. Many of these polycarbonate resins have been obtained using bisphenol A as a monomer. In recent years, in these fields of application, thinner and lighter molded products have been developed, and further improvements in the performance of molding materials are required. The development of a polycarbonate resin having a more transparent appearance, in particular, less coloring and higher transparency has been desired, and several proposals have been made.

  For example, a method for producing an aromatic polycarbonate in which the amount of a specific compound in bisphenol A is defined (Patent Documents 1 and 2), and an optical polycarbonate composition in which the amount of metal or ionic impurities in bisphenol A is defined. A method (Patent Document 3), a method for producing an aromatic polycarbonate in which aldehydes in bisphenol A are specified (Patent Document 4), and the like have been reported.

Japanese Patent Laid-Open No. 08-104747 Japanese Patent Laid-Open No. 08-104748 Japanese Patent No. 3103652 International Publication No. 2002/22708 Pamphlet

  Under such circumstances, an object of the present invention is to provide a polycarbonate resin excellent in hue and thermal stability of a polycarbonate resin obtained by using a specific aromatic dihydroxy compound, and a method for producing the same.

  The present inventors diligently studied to achieve the above object, and as a result, by using a specific aromatic dihydroxy compound, specific impurities of the aromatic dihydroxy compound were reduced, and as a result, the hue and thermal stability were excellent. The inventors have found that a polycarbonate resin can be obtained, and have completed the present invention.

（一般式（１）中、Ｒ₁及びＲ₂は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｘは、単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）

（一般式（２）中、Ｒ₁、Ｒ₂及びＲ₃は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｒ₄は、水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示す。また、Ｘは単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）

＜２＞ 前記ジヒドロキシ化合物中、下記一般式（３）で表される化合物の含有量が２０００ｐｐｍ以下である前記＜１＞に記載のポリカーボネート樹脂の製造方法。

（一般式（３）中、Ｒ₁は、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｘは、単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）
＜３＞ 前記ジヒドロキシ化合物中、下記一般式（４）で表される化合物の含有量が２００ｐｐｍ以下である前記＜１＞又は＜２＞に記載のポリカーボネート樹脂の製造方法。

（一般式（４）中、Ｒ₁、Ｒ₂、Ｒ₃及びＲ₄は、それぞれ独立に、水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｘは、単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。但し、一般式（４）における２つの水酸基の結合位置が、それぞれのフェニル環上のＸに対して４位（パラ位）である場合を除く。）

＜４＞ 前記一般式（１）から（４）のＸの置換若しくは無置換のアルキリデン基が、

である前記＜１＞乃至＜３＞のいずれかに記載のポリカーボネート樹脂の製造方法。
（Ｒ₅及びＲ₆は、それぞれ独立に、水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｚは、置換若しくは無置換の炭素数４〜炭素数２０のアルキレン基を示す。）
＜５＞ 前記一般式（１）で表される化合物が下記一般式（５）で表される化合物を原料として製造されたものであり、下記一般式（５）で表される化合物において、下記一般式（６）で表される化合物の含有量が５００ｐｐｍ以下である前記＜１＞に記載のポリカーボネート樹脂の製造方法。

（一般式（５）中、Ｒ₁は、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示す。）

（一般式（６）中、Ｒ₁及びＲ₃は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示す。）
＜６＞ 前記一般式（１）で表される化合物が、２，２−ビス（４−ヒドロキシ−３−メチルフェニル）プロパン、１，１−ビス（４−ヒドロキシ−３−メチルフェニル）シクロヘキサン、１，１−ビス（４−ヒドロキシ−３−メチルフェニル）−３，５，５−トリメチルシクロヘキサン及び１，１−ビス（４−ヒドロキシ−３−メチルフェニル）シクロドデカンからなる群より選ばれた少なくとも１種である前記＜１＞乃至＜５＞のいずれかに記載のポリカーボネート樹脂の製造方法。 That is, the present invention relates to a method for producing a polycarbonate resin according to the following <1> to <6>.
<1> A method for producing a polycarbonate resin obtained by using a dihydroxy compound containing a compound represented by the following general formula (1) as a main component and a carbonate-forming compound, wherein in the dihydroxy compound, the following general formula (2) The manufacturing method of the polycarbonate resin whose content of the compound represented is 100 ppm or less.

(In the general formula (1), R ₁ and R ₂ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single group. And represents a bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)

(In the general formula (2), R ₁ , R ₂ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group; ₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group. Represents a substituted or unsubstituted sulfur atom or an oxygen atom.)

<2> The method for producing a polycarbonate resin according to <1>, wherein the content of the compound represented by the following general formula (3) is 2000 ppm or less in the dihydroxy compound.

(In General Formula (3), R ₁ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or It represents an unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)
<3> The method for producing a polycarbonate resin according to <1> or <2>, wherein the content of the compound represented by the following general formula (4) in the dihydroxy compound is 200 ppm or less.

(In General Formula (4), R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted group. Represents an aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom, provided that the bonding positions of two hydroxyl groups in the general formula (4) Except for the 4-position (para-position) to X on each phenyl ring.)

<4> The substituted or unsubstituted alkylidene group of X in the general formulas (1) to (4) is

The method for producing a polycarbonate resin according to any one of <1> to <3>.
(R ₅ and R ₆ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and Z represents a substituted or unsubstituted aryl group. An alkylene group having 4 to 20 carbon atoms is shown.)
<5> The compound represented by the general formula (1) is produced using a compound represented by the following general formula (5) as a raw material. In the compound represented by the following general formula (5), The method for producing a polycarbonate resin according to <1>, wherein the content of the compound represented by the general formula (6) is 500 ppm or less.

(In the general formula (5), R ₁ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group.)

(In General Formula (6), R ₁ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group.)
<6> The compound represented by the general formula (1) is 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-methylphenyl) cyclohexane, At least selected from the group consisting of 1,1-bis (4-hydroxy-3-methylphenyl) -3,5,5-trimethylcyclohexane and 1,1-bis (4-hydroxy-3-methylphenyl) cyclododecane The manufacturing method of the polycarbonate resin in any one of said <1> thru | or <5> which is 1 type.

（一般式（１）中、Ｒ₁及びＲ₂は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｘは、単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）

（一般式（２）中、Ｒ₁、Ｒ₂及びＲ₃は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｒ₄は水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示す。また、Ｘは単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）
＜８＞ 下記一般式（１）で表される化合物を主成分として含むジヒドロキシ化合物とカーボネート形成性化合物により得られるポリカーボネート樹脂であって、該ジヒドロキシ化合物中、下記一般式（２）で表される化合物の含有量が１００ｐｐｍ以下であり、得られたポリカーボネート樹脂の、熱滞留時の色相変化値（ΔＹＩ）が０．５以下であるポリカーボネート樹脂。

（一般式（１）中、Ｒ₁及びＲ₂は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｘは、単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）

（一般式（２）中、Ｒ₁、Ｒ₂及びＲ₃は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｒ₄は水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示す。また、Ｘは単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。） The present invention also relates to the following <7> and <8> polycarbonate resins.
<7> A polycarbonate resin obtained from a dihydroxy compound containing a compound represented by the following general formula (1) as a main component and a carbonate-forming compound, and represented by the following general formula (2) in the dihydroxy compound. The polycarbonate resin whose content of a compound is 100 ppm or less and whose initial hue (YI) of the obtained polycarbonate resin is 2.0 or less.

(In the general formula (1), R ₁ and R ₂ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single group. And represents a bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)

(In the general formula (2), R ₁ , R ₂ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group; ₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, A substituted or unsubstituted sulfur atom or an oxygen atom is shown.)
<8> A polycarbonate resin obtained from a dihydroxy compound containing a compound represented by the following general formula (1) as a main component and a carbonate-forming compound, and represented by the following general formula (2) in the dihydroxy compound. A polycarbonate resin having a compound content of 100 ppm or less and a hue change value (ΔYI) during heat retention of the obtained polycarbonate resin of 0.5 or less.

(In the general formula (1), R ₁ and R ₂ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single group. And represents a bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)

(In the general formula (2), R ₁ , R ₂ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group; ₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, A substituted or unsubstituted sulfur atom or an oxygen atom is shown.)

  According to the present invention, by using a specific aromatic dihydroxy compound, a polycarbonate resin having a good hue and thermal stability and a method for producing the same are provided.

（一般式（２）中、Ｒ₁、Ｒ₂及びＲ₃は、それぞれ独立に、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｒ₄は水素原子、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示す。また、Ｘは単結合、カルボニル基、置換若しくは無置換のアルキリデン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）
なお、本発明において「主成分として含む」とは、当該ジヒドロキシ化合物における対象成分の比率が５０重量％以上、好ましくは７５重量％以上、さらに好ましくは９０重量％以上（１００重量％を含む）であることをいう。 The present invention will be specifically described below.
First, this invention is a manufacturing method of polycarbonate resin obtained by the dihydroxy compound which contains the compound represented by following General formula (1) as a main component, and a carbonate formation compound, Comprising: In this dihydroxy compound, following general formula ( The content of the compound represented by 2) is 100 ppm or less, and relates to a method for producing a polycarbonate resin.

(In the general formula (2), R ₁ , R ₂ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group; ₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, A substituted or unsubstituted sulfur atom or an oxygen atom is shown.)
In the present invention, “containing as a main component” means that the ratio of the target component in the dihydroxy compound is 50% by weight or more, preferably 75% by weight or more, more preferably 90% by weight or more (including 100% by weight). Say something.

In the present invention, the compound that is the main component of the dihydroxy compound that is the raw material of the polycarbonate resin has the structure of the general formula (1), and in the general formula (1), R ₁ and R ₂ are each independently , A substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group.
Examples of the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms of R ₁ and R ₂ include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec -Butyl group, tert-butyl group, n-pentyl group, sec-pentyl group, n-hexyl group, n-heptyl group, n-octyl group and the like. Examples of the substituted or unsubstituted aryl group include: A phenyl group, a benzyl group, a tolyl group, 4-methylphenyl group, a naphthyl group, etc. are mentioned.
Among these, R ₁ and R ₂ are preferably a methyl group, an ethyl group, an n-propyl group, or a 4-methylphenyl group, and particularly preferably a methyl group.
Here, the bonding position of R ₁ and R ₂ in the general formula (1) is an arbitrary position selected from the 2-position, 3-position, 5-position and 6-position with respect to X on each phenyl ring. Among these, the third and fifth positions are preferable.

In the general formula (1), X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom. Examples of the substituted or unsubstituted sulfur atom include —S— and —SO ₂ —.

In the general formula (1), X is preferably a substituted or unsubstituted alkylidene group described below.

Here, R ₅ and R ₆ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and Z is substituted or unsubstituted. A substituted alkylene group having 4 to 20 carbon atoms is shown.
Examples of the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms of R ₅ and R ₆ include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec -Butyl group, tert-butyl group, n-pentyl group, sec-pentyl group, n-hexyl group, n-heptyl group, n-octyl group and the like. Examples of the substituted or unsubstituted aryl group include a phenyl group, a benzyl group, a tolyl group, a 4-methylphenyl group, and a naphthyl group.
Among these, R ₅ and R ₆ are preferably a methyl group, an ethyl group, an n-propyl group, or a 4-methylphenyl group, and particularly preferably a methyl group.
Z is bonded to the carbon to which two phenyl groups are bonded in the general formula (1) to form a substituted or unsubstituted divalent carbocycle. Examples of the divalent carbocycle include a cycloalkylidene group such as a cyclopentylidene group, a cyclohexylidene group, a cycloheptylidene group, a cyclododecylidene group, an adamantylidene group (preferably a carbon number of 5 To 8 carbon atoms. Examples of the substituted ones include those having these methyl substituents and ethyl substituents. Among these, a cyclohexylidene group and a methyl-substituted product of a cyclohexylidene group are preferable.

Specific examples of the compound represented by the general formula (1) include 2,2-bis (4-hydroxy-3-methylphenyl) propane and 1,1-bis (4-hydroxy-3-methylphenyl). ) Cyclohexane, 1,1-bis (4-hydroxy-3-methylphenyl) -3,5,5-trimethylcyclohexane, 1,1-bis (4-hydroxy-3-methylphenyl) cyclododecane, 1,1- Bis (4-hydroxy-3-methylphenyl) adamantane, 1,4-bis (4-hydroxy-3-methylphenyl) adamantane, 2,2-bis (4-hydroxy-3-ethylphenyl) propane, 2,2 -Bis (4-hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-cyclohexylphenyl) propane, , 2-bis (4-hydroxy-3-phenylphenyl) propane, 5,5-bis (4-hydroxy-3-methylphenyl) hexahydro-4,7-methanoindane, 2,2-bis (4-hydroxy-3) -Methylphenyl) sulfone, 2,2-bis (4-hydroxy-3-methylphenyl) sulfide, 3,3'-dimethylbiphenol and the like.
Among these, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-methylphenyl) cyclohexane, 1,1-bis (4-hydroxy-3-) Methylphenyl) -3,5,5-trimethylcyclohexane, 1,1-bis (4-hydroxy-3-methylphenyl) cyclododecane, 5,5-bis (4-hydroxy-3-methylphenyl) hexahydro-4, 7-methanoindane and 3,3′-dimethylbiphenol are preferable, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-methylphenyl) -3,5 , 5-trimethylcyclohexane and 1,1-bis (4-hydroxy-3-methylphenyl) cyclododecane are more preferred, Bis (4-hydroxy-3-methylphenyl) propane and 1,1-bis (4-hydroxy-3-methylphenyl) cyclohexane are particularly preferred. These dihydroxy compounds can be used alone or in admixture of two or more.

The dihydroxy compound may contain other dihydroxy compounds in addition to the compound represented by the general formula (1) as long as the characteristics are not substantially impaired.
The other dihydroxy compounds are not particularly limited, but specifically, aliphatic dihydroxy compounds such as ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, , 2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol and the like.
Also, bis (hydroxyanneal) alkanes such as 2,2-bis (4-hydroxyphenyl) propane (also known as bisphenol A), bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, etc. Bis (hydroxyanneal) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclopentane and 1,1-bis (4-hydroxyphenyl) cyclohexane; 9,9-bis (4-hydroxyphenyl) Cardio structure-containing bisphenols such as fluorene and 9,9-bis (4-hydroxy-3-methylphenyl) fluorene; 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether, etc. Dihydroxydiaryl ethers; 4,4′-dihydroxydiphe Dihydroxy diaryl sulfides such as nyl sulfide and 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide; 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfoxide and the like Dihydroxy diaryl sulfoxides; dihydroxy diaryl sulfones such as 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone; hydroquinone, resorcin, 4,4′-dihydroxydiphenyl, etc. Aromatic dihydroxy compounds are mentioned. Among these, bis (hydroxyanneal) alkanes are preferable, and 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) is particularly preferable from the viewpoint of impact resistance.

Next, the dihydroxy compound of the present invention is required to have a content of the compound represented by the general formula (2) of 100 ppm or less, preferably 80 ppm or less, more preferably 50 ppm or less, and further preferably 30 ppm or less. And When the content of the compound represented by the general formula (2) exceeds 100 ppm, the reactivity tends to deteriorate in the interfacial polymerization method, and the amount of the OH group terminal of the polymer increases, and the hue and thermal stability deteriorate. . Even in the melt polymerization method, the hue and thermal stability tend to deteriorate, which is not preferable.
In the general formula (2), R ₁ , R ₂ and R ₃ each independently represent a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and R ₄ Represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group. X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.

Here, in General Formula (2), R ₁ , R _2, and X have the same meaning as in General Formula (1). Examples of the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms of R ₃ and R ₄ include, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and an isobutyl group. , Sec-butyl group, tert-butyl group, n-pentyl group, sec-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, and the like. As the substituted or unsubstituted aryl group, For example, a phenyl group, a benzyl group, a tolyl group, 4-methylphenyl group, a naphthyl group, etc. are mentioned.
Here, the bonding positions of R ₁ , R ₂ , R ₃ and R ₄ in the general formula (2) are arbitrarily selected from the 2-position, 3-position, 5-position and 6-position with respect to X on each phenyl ring. Is the position.

Specific examples of the aromatic dihydroxy compound represented by the general formula (2) include the following chemical formulas (2A) to (2H) when R ₄ is a hydrogen atom.

Moreover, as a case where R ₄ is other than a hydrogen atom, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 1,1-bis (4-hydroxy-3,5-dimethylphenyl) cyclohexane, 1,1-bis (4-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylcyclohexane, 1,1-bis (4-hydroxy-3,5-dimethylphenyl) adamantane, 1,4- Bis (4-hydroxy-3,5-dimethylphenyl) adamantane, 2,2-bis (3-ethyl-4-hydroxy-5-methylphenyl) propane, 2,2-bis (3-tert-butyl-4- Hydroxy-5-methylphenyl) propane, 2,2bis (3-cyclohexyl-4-hydroxy-5-methylphenyl) propane, 2,2-bis (4-hydride) Xyl-3-methyl-5-phenylphenyl) propane, 2,2-bis (3,5-diethyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-di-tert-butyl-4- Hydroxyphenyl) propane, 2,2-bis (3,5-di-cyclohexyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-diphenylphenyl) propane, 5,5-bis (4-hydroxy-3,5-dimethylphenyl) hexahydro-4,7-methanoindane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) sulfone, 2,2-bis (4-hydroxy-3) , 5-dimethylphenyl) sulfide, 3,3 ′, 5,5′-tetramethylbiphenol, and the like.

  Furthermore, in the present invention, the content of the compound represented by the following general formula (3) in the dihydroxy compound is preferably 2000 ppm or less, more preferably 1800 ppm or less, and more preferably 1700 ppm or less. Further preferred. When the content of the compound represented by the general formula (3) is large, the hue and thermal stability of the polymer may be deteriorated.

（一般式（３）中、Ｒ₁は、置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示し、Ｘは、単結合、置換若しくは無置換のアルキレン基、置換若しくは無置換の硫黄原子、又は酸素原子を示す。）
ここに、Ｒ₁、Ｘは、上記一般式（１）中のＲ₁、Ｘと同義であり、同様な基や原子が例示される。

(In General Formula (3), R ₁ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single bond, substituted or unsubstituted. An alkylene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)
Here, R ₁ and X are synonymous with R ₁ and X in the general formula (1), and the same groups and atoms are exemplified.

  Specific examples of the compound represented by the general formula (3) include the following chemical formulas (3A) to (3H).

Furthermore, in this invention, content of the compound represented by following General formula (4) in the said dihydroxy compound is 200 ppm or less, Preferably it is 160 ppm or less, More preferably, it is 100 ppm or less.
When the content of the compound represented by the following general formula (4) is large, the hue and thermal stability of the polymer may be deteriorated.

In the general formula (4), R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl. X represents a single bond, a substituted or unsubstituted alkylene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.

Examples of the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms of R ₁ , R ₂ , R ₃ and R ₄ include, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and n-butyl. Group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, sec-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, etc., substituted or unsubstituted aryl Examples of the group include a phenyl group, a benzyl group, a tolyl group, a 4-methylphenyl group, and a naphthyl group. In addition, X is synonymous with X in the said General formula (1), and the same group and atom are illustrated.

  Specific examples of the compound represented by the general formula (4) include the following chemical formulas (4A) to (4F).

In addition, in order to obtain the compound represented by the said General formula (1) whose content of the compound represented by the said General formula (2) of this invention is 100 ppm or less, it represents with the following General formula (6). It is desirable to use as a raw material a compound represented by the following general formula (5) having a compound content of 500 ppm or less, preferably 300 ppm or less, more preferably 200 ppm or less, and even more preferably 100 ppm or less.
In order to bring the compound represented by the general formula (6) within the above range, Japanese Patent Publication No. 48-42863, Japanese Patent Publication No. 63-6533, Japanese Patent Publication No. 57-11933, Japanese Patent Publication No. Hei 5-97739. Known distillation methods, crystallization methods, extraction methods and the like described in Japanese Patent Publication No. 4,001,341 pamphlet and the like may be appropriately selected.

前記一般式（５）中Ｒ₁、前記一般式（６）中、Ｒ₁及びＲ₃は、それぞれ独立に置換若しくは無置換の炭素数１〜炭素数２０のアルキル基、又は置換若しくは無置換のアリール基を示す。
ここに、前記一般式（５）中Ｒ₁、前記一般式（６）中、Ｒ₁、Ｒ₃は、上記一般式（１）又は（２）中のＲ₁、Ｒ₃と同義であり、同様な基が例示される。

R _{1 in the} general formula (5) and R ₁ and R ₃ in the general formula (6) are each independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted group. An aryl group is shown.
Here, the formula (5) Medium R _1, in the general formula (6), R _1, R ₃ has the same meaning as R _1, R ₃ in the general formula (1) or (2), Similar groups are exemplified.

Specific examples of the general formula (5) include 2-methylphenol (o-cresol), 3-methylphenol (m-cresol), 4-methylphenol (p-cresol) and the like.
Specific examples of the general formula (6) include 2,3-dimethylphenol (2,3-xylenol), 2,4-dimethylphenol (2,4-xylenol), 2,5-dimethylphenol (2, 5-xylenol), 2,6-dimethylphenol (2,6-xylenol), 3,4-dimethylphenol (3,4-xylenol), 3,5-dimethylphenol (3,5-xylenol) and the like. .

Next, in the present invention, the carbonate-forming compound that is another raw material of the polycarbonate resin includes a carbonic acid diester compound and carbonyl chloride.
Here, as a carbonic acid diester compound, the compound represented by following General formula (7) is mentioned.

In General Formula (7), A ′ is an optionally substituted linear, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms. Two A ′ may be the same or different from each other.
In addition, as a substituent on A ′, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a phenyl group, a phenoxy group, a vinyl group, a cyano group, and an ester group Amide group, nitro group and the like.

  Specific examples of the carbonic acid diester compound include substituted diphenyl carbonates such as diphenyl carbonate and ditolyl carbonate, and dialkyl carbonates such as dimethyl carbonate, diethyl carbonate, and di-t-butyl carbonate. Among these, diphenyl carbonate (hereinafter sometimes abbreviated as “DPC”) and substituted diphenyl carbonate are preferable. These carbonic acid diesters can be used alone or in admixture of two or more.

  Moreover, the amount of the carbonic acid diester compound is preferably 50 mol% or less, more preferably 30 mol% or less, and may be substituted with dicarboxylic acid or dicarboxylic acid ester. Typical dicarboxylic acids or dicarboxylic acid esters include terephthalic acid, isophthalic acid, diphenyl terephthalate, diphenyl isophthalate, and the like. When substituted with such a dicarboxylic acid or dicarboxylic acid ester, a polyester carbonate is obtained.

<Production method of polycarbonate resin>
Next, a method for producing a polycarbonate resin to which the present embodiment is applied will be described. The polycarbonate resin to which the present embodiment is applied is obtained by polymerization using a dihydroxy compound and a carbonyl compound, specifically, an organic phase and an aqueous phase in which the dihydroxy compound and carbonyl chloride are not arbitrarily mixed. The interfacial polycondensation method (hereinafter abbreviated as “interface method”) for producing a polycarbonate resin by reacting at the interface, and the ester in the molten state in the presence of a transesterification reaction catalyst. There is a melt polycondensation method (hereinafter abbreviated as “melting method”) in which a polycarbonate resin is produced by an exchange reaction.
Hereinafter, each of the interface method and the melting method will be specifically described.

<Interface method>
The polycarbonate resin production method by the interfacial method usually involves preparing an aqueous alkali solution of a dihydroxy compound, performing an interfacial polycondensation reaction between the dihydroxy compound and carbonyl chloride in the presence of an amine compound used as a polymerization catalyst, A polycarbonate resin is obtained through the steps of washing, washing and drying. Specifically, the polycarbonate resin production process by the interfacial method includes a raw material process for preparing raw materials such as monomer components, an oligomerization process in which an oligomerization reaction is performed, a polycondensation process in which a polycondensation reaction using an oligomer is performed, A washing step for washing the reaction solution after the polycondensation reaction by alkali washing, acid washing, water washing, a resin isolation step for pre-concentrating the washed reaction solution and isolating the polycarbonate resin after granulation, an isolated polycarbonate At least a drying step of drying the resin particles is provided. Hereinafter, each step will be described.

(Primary process)
In the original process, an aqueous solution of a dihydroxy compound containing the compound represented by the general formula (1) as a main component and an alkali metal compound such as sodium hydroxide (NaOH) or an alkali such as magnesium hydroxide in the original tank. A raw material such as an alkaline aqueous solution of a dihydroxy compound containing an aqueous solution of an earth metal compound, demineralized water (DMW), and a reducing agent such as hydrosulfite (HS) as necessary is prepared.

(Alkali metal compound or alkaline earth metal compound)
As the alkali metal compound or alkaline earth metal compound, a hydroxide is usually preferable, and examples thereof include sodium hydroxide, lithium hydroxide, potassium hydroxide, magnesium hydroxide, and calcium hydroxide. Among these, sodium hydroxide is particularly preferable. The ratio of the alkali metal compound or alkaline earth metal compound to the dihydroxy compound is usually 1.0 to 1.5 (equivalent ratio), preferably 1.02 to 1.04 (equivalent ratio). When the ratio of the alkali metal compound or alkaline earth metal compound is excessively large or excessively small, it affects the terminal group of the carbonate oligomer obtained in the oligomerization step described later, and as a result, the polycondensation reaction tends to be abnormal. There is.

(Oligomerization process)
Next, in the oligomerization step, the alkaline aqueous solution prepared in the original preparation step is dihydroxylated in a predetermined reactor in the presence of an organic solvent such as carbonyl chloride (COCl ₂ ) and methylene chloride (CH ₂ Cl ₂ ). A phosgenation reaction of the compound is performed.
Subsequently, a condensation catalyst such as triethylamine (TEA) and a chain terminator such as pt-butylphenol (pTBP) are added to the mixed solution in which the phosgenation reaction of the dihydroxy compound is performed, and the oligomerization reaction of the dihydroxy compound Is done.
Next, the oligomerization reaction liquid of the dihydroxy compound was introduced into a predetermined stationary separation tank after further oligomerization reaction, and the organic phase containing the carbonate oligomer and the aqueous phase were separated and separated. The organic phase is fed to the polycondensation process.
Here, the residence time in the oligomerization step from when the alkaline aqueous solution of the dihydroxy compound is supplied to the reactor in which the phosgenation reaction of the dihydroxy compound is performed until entering the stationary separation tank is usually 120 minutes or less, preferably 30 minutes to 60 minutes.

(Carbonyl chloride)
The carbonyl chloride used in the oligomerization step (hereinafter sometimes referred to as “CDC”) is usually used in liquid or gaseous form. From the viewpoint of temperature control, the CDC is preferably in a liquid state, and a reaction pressure that can maintain the liquid state at the reaction temperature is selected.
The preferred amount of CDC used in the oligomerization step is appropriately selected depending on the reaction conditions, particularly the reaction temperature and the concentration of the metal salt of the dihydroxy compound in the aqueous phase, and is not particularly limited. Usually, the amount of CDC is 1 mol to 2 mol, preferably 1.05 mol to 1.5 mol, per 1 mol of the dihydroxy compound. When the amount of CDC used is excessively large, unreacted CDC increases and the basic unit tends to be extremely deteriorated. On the other hand, if the amount of CDC used is excessively small, the amount of chloroformate group is insufficient and proper molecular weight elongation tends not to be performed.

(Organic solvent)
In the oligomerization step, an organic solvent is usually used. As the organic solvent, any reaction product such as carbonyl chloride and carbonate oligomer, polycarbonate resin, etc. is dissolved at the reaction temperature and reaction pressure in the oligomerization step and is not compatible with water (or does not form a solution with water). An inert organic solvent is mentioned.
Examples of such inert organic solvents include aliphatic hydrocarbons such as hexane and n-heptane; chlorinations such as dichloromethane, chloroform, carbon tetrachloride, dichloroethane, trichloroethane, tetrachloroethane, dichloropropane, and 1,2-dichloroethylene. Aliphatic hydrocarbons; aromatic hydrocarbons such as benzene, toluene and xylene; chlorinated aromatic hydrocarbons such as chlorobenzene, o-dichlorobenzene and chlorotoluene; and other substituted aromatic hydrocarbons such as nitrobenzene and acetophenone It is done.
Among these, for example, chlorinated hydrocarbons such as dichloromethane or chlorobenzene are preferably used. These inert organic solvents can be used alone or as a mixture with other solvents.

(Condensation catalyst)
The oligomerization reaction can be performed in the presence of a condensation catalyst. The addition timing of the condensation catalyst is preferably after CDC is consumed. The condensation catalyst can be arbitrarily selected from many condensation catalysts used in the two-phase interfacial condensation method. For example, trialkylamine, N-ethylpyrrolidone, N-ethylpiperidine, N-ethylmorpholine, N-isopropylpiperidine, N-isopropylmorpholine and the like can be mentioned. Of these, triethylamine and N-ethylpiperidine are preferable.

(Chain terminator)
In the present embodiment, monophenol is usually used as a chain terminator in the oligomerization step. Examples of monophenols include phenols; alkylphenols having 1 to 20 carbon atoms such as pt-butylphenol and p-cresol; halogenated phenols such as p-chlorophenol and 2,4,6-tribromophenol. Can be mentioned. The usage-amount of monophenol is suitably selected according to the molecular weight of the carbonate oligomer obtained, and is 0.5 mol%-10 mol% normally with respect to a dihydroxy compound.

In the interface method, the molecular weight of the polycarbonate resin is determined by the addition amount of a chain terminator such as monophenol. For this reason, from the viewpoint of controlling the molecular weight of the polycarbonate resin, the chain stopper is preferably added immediately after the consumption of the carbonate-forming compound is completed and before the molecular weight elongation starts.
When monophenol is added in the presence of a carbonate-forming compound, a large amount of condensates (diphenyl carbonates) of monophenols are produced, and it is difficult to obtain a polycarbonate resin having a target molecular weight. If the addition time of monophenol is extremely delayed, it becomes difficult to control the molecular weight, and furthermore, the resin has a specific shoulder on the low molecular weight side of the molecular weight distribution, and there is a tendency that problems such as dripping occur during molding.

(Branching agent)
In the oligomerization step, any branching agent can be used. Examples of such a branching agent include 2,4-bis (4-hydroxyphenylisopropyl) phenol, 2,6-bis (2-hydroxy-5-methylbenzyl) -4-methylphenol, 2- (4- Hydroxyphenyl) -2- (2,4-dihydroxyphenyl) propane, 1,4-bis (4,4′-dihydroxytriphenylmethyl) benzene and the like. In addition, 2,4-dihydroxybenzoic acid, trimesic acid, cyanuric chloride and the like can also be used. Among these, a branching agent having at least three phenolic hydroxyl groups is preferable. The amount of branching agent used is appropriately selected according to the degree of branching of the carbonate oligomer obtained, and is usually 0.05 mol% to 2 mol% with respect to the dihydroxy compound.

In the oligomerization step, when the two-phase interfacial condensation method is employed, the organic phase containing the dihydroxy compound and the alkali metal compound or alkali are contacted prior to the contact between the aqueous solution of the alkali metal compound or alkaline earth metal compound of the dihydroxy compound and carbonyl chloride. It is particularly preferred that an aqueous phase containing an earth metal compound is brought into contact with an organic phase that is not arbitrarily mixed with water to form an emulsion.
Examples of means for forming such an emulsion include a stirrer having a predetermined stirring blade, a homogenizer, a homomixer, a colloid mill, a flow jet mixer, a dynamic mixer such as an ultrasonic emulsifier, a static mixer, and the like. It is preferable to use a mixer. The emulsion usually has a droplet diameter of 0.01 μm to 10 μm and has emulsion stability.
The emulsion state of the emulsion is usually represented by the Weber number or P / q (additional power value per unit volume). The Weber number is preferably 10,000 or more, more preferably 20,000 or more, and most preferably 35,000 or more. Also, the upper limit is about 1,000,000 or less. P / q is preferably 200 kg · m / liter or more, more preferably 500 kg · m / liter or more, and most preferably 1,000 kg · m / liter or more.

  The contact between the emulsion and carbonyl chloride (CDC) is preferably carried out under mixing conditions weaker than the emulsification conditions described above in order to suppress dissolution of CDC in the organic phase. The Weber number is less than 10,000, preferably less than 5,000, and more preferably less than 2,000. Further, P / q is less than 200 kg · m / liter, preferably less than 100 kg · m / liter, and more preferably less than 50 kg · m / liter. CDC contact can be achieved by introducing CDC into a tubular reactor or tank reactor.

  The reaction temperature in the oligomerization step is usually 80 ° C. or lower, preferably 60 ° C. or lower, more preferably 10 ° C. to 50 ° C. The reaction time is appropriately selected depending on the reaction temperature, and is usually 0.5 minutes to 10 hours, preferably 1 minute to 2 hours. If the reaction temperature is excessively high, side reactions cannot be controlled and the CDC basic unit tends to deteriorate. If the reaction temperature is excessively low, this is a favorable situation in terms of reaction control, but the refrigeration load increases and the cost tends to increase.

  The concentration of the carbonate oligomer in the organic phase may be in a range in which the obtained carbonate oligomer is soluble, and is specifically about 10 wt% to 40 wt%. The proportion of the organic phase is preferably a volume ratio of 0.2 to 1.0 with respect to the aqueous phase containing the aqueous alkali metal salt solution or alkaline earth metal salt solution of the dihydroxy compound.

(Polycondensation process)
Next, in the polycondensation step, the organic phase containing the carbonate oligomer separated from the aqueous phase in the stationary separation tank is transferred to an oligomer storage tank having a stirrer. A condensation catalyst such as triethylamine (TEA) is further added to the oligomer storage tank.
Subsequently, the organic phase stirred in the oligomer storage tank is introduced into a predetermined polycondensation reaction tank. Subsequently, an organic solvent such as demineralized water (DMW) or methylene chloride (CH ₂ Cl ₂ ) is added to the polycondensation reaction tank. Then, an aqueous sodium hydroxide solution is supplied and mixed with stirring to carry out a polycondensation reaction of the carbonate oligomer.

Thereafter, the polycondensation reaction liquid in the polycondensation reaction tank is successively introduced successively into a plurality of polycondensation reaction tanks, and the polycondensation reaction of the carbonate oligomer is completed.
Here, in the polycondensation step, the residence time in the polycondensation reaction tank in which the polycondensation reaction of the carbonate oligomer is continuously performed is usually 12 hours or less, preferably 0.5 to 5 hours.
As a preferred embodiment of the polycondensation step, first, an organic phase containing a carbonate oligomer and an aqueous phase are separated, and an inert organic solvent is added to the separated organic phase as necessary to adjust the concentration of the carbonate oligomer. In this case, the amount of the inert organic solvent is adjusted so that the concentration of the polycarbonate resin in the organic phase obtained by the polycondensation reaction is 5% by weight to 30% by weight. Next, an aqueous solution containing water and an alkali metal compound or an alkaline earth metal compound is newly added, and in order to further adjust the polycondensation conditions, a condensation catalyst is preferably added, and a polycondensation reaction is performed according to an interfacial polycondensation method. . The ratio of the organic phase to the aqueous phase in the polycondensation reaction is preferably about volume ratio of organic phase: aqueous phase = 1: (0.2-1).

Examples of the alkali metal compound or alkaline earth metal compound include compounds similar to those used in the oligomerization step described above. Of these, sodium hydroxide is preferred industrially. The amount of the alkali metal compound or alkaline earth metal compound used may be more than the amount that the reaction system is always kept alkaline during the polycondensation reaction. In addition, it may be divided and added as appropriate during the polycondensation reaction.
When the amount of the alkali metal compound or alkaline earth metal compound used is excessively large, the hydrolysis reaction as a side reaction tends to proceed. Therefore, the concentration of the alkali metal compound or alkaline earth metal compound contained in the aqueous phase after the completion of the polycondensation reaction is 0.05N or more, preferably 0.05N to 0.3N.
The temperature of the polycondensation reaction in the polycondensation step is usually around room temperature. The reaction time is about 0.5 to 5 hours, preferably about 1 to 3 hours.

(Washing process)
Next, after the polycondensation reaction in the polycondensation reaction tank is completed, the polycondensation reaction solution is subjected to alkali washing with an alkali washing solution, acid washing with an acid washing solution, and water washing with washing water by a known method. In addition, the total residence time of the washing step is usually 12 hours or less, preferably 0.5 to 6 hours.

(Resin isolation step)
In the resin isolation step, first, an organic solvent solution containing the polycarbonate resin washed in the washing step is prepared as a concentrated solution concentrated to a predetermined solid content concentration. The solid content concentration of the polycarbonate resin in the concentrate is usually 5% to 35% by weight, preferably 10% to 30% by weight.
Next, the concentrate is continuously supplied to a predetermined granulation tank, and stirred and mixed with demineralized water (DMW) at a predetermined temperature. And the granulation process which evaporates an organic solvent is performed, maintaining a suspended state in water, and the water slurry containing a polycarbonate resin granular material is formed.
Here, the temperature of the demineralized water (DMW) is usually 37 ° C to 67 ° C, preferably 40 ° C to 50 ° C. Moreover, the solidification temperature of polycarbonate resin by the granulation process performed in a granulation tank is 37 to 67 degreeC normally, Preferably, it is 40 to 50 degreeC.
The water slurry containing the polycarbonate resin powder continuously discharged from the granulation tank is then continuously introduced into a predetermined separator, and water is separated from the water slurry.

(Drying process)
In the drying process, in the separator, the polycarbonate resin powder from which water has been separated from the water slurry is continuously supplied to a predetermined dryer, retained for a predetermined residence time, and then continuously extracted. . Examples of the dryer include a fluidized bed dryer. A plurality of fluidized bed dryers may be connected in series to continuously perform the drying process.
Here, the dryer usually has a heating means such as a heat medium jacket, for example, with water vapor, usually 0.1 MPa-G to 1.0 MPa-G, preferably 0.2 MPa-G to 0. .6 MPa-G. Thus, the temperature of nitrogen (N ₂₎ flowing through the dryer, usually, 100 ° C. to 200 DEG ° C., preferably, it is held in 120 ° C. to 180 ° C..

<Melting method>
Next, the melting method will be described.
In the melting method, a polycarbonate resin is produced by continuously performing a melt polycondensation reaction in the presence of a transesterification catalyst using a dihydroxy compound and a carbonyl compound as raw materials.

(Transesterification catalyst)
Examples of the transesterification catalyst used in the production method of the present invention include a catalyst usually used in producing a polycarbonate resin by an ester exchange method, and are not particularly limited.
In general, for example, basic compounds such as alkali metal compounds, alkaline earth metal compounds, beryllium compounds, magnesium compounds, basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds can be used. Among these, an alkali metal compound, an alkaline earth metal compound, a beryllium compound, and a magnesium compound are preferable for practical use. These transesterification catalysts may be used alone or in combination of two or more.

The amount of the transesterification catalyst used is usually in the range of 1 × 10 ⁻⁹ to 1 × 10 ⁻³ mol per 1 mol of the dihydroxy compound, in order to obtain an aromatic polycarbonate resin excellent in molding characteristics and hue. In the case of using an alkali metal compound and / or an alkaline earth metal compound, the amount of the transesterification catalyst is preferably 1.0 × 10 ⁻⁸ to 1 × 10 ⁻⁴ mol with respect to 1 mol of the dihydroxy compound. Within the range, more preferably within the range of 1.0 × 10 ⁻⁸ to 1 × 10 ⁻⁵ mol, and particularly preferably within the range of 1.0 × 10 ^{−7 to} 5.0 × 10 ⁻⁶ mol. . If the amount is less than the above lower limit, the polymerization activity necessary for producing a polycarbonate resin having a desired molecular weight cannot be obtained, and the polymer has a small amount of branching components, and sufficient molding characteristics cannot be obtained. On the other hand, when the amount is larger than the upper limit, the polymer hue is deteriorated, the amount of branching components is too large, the fluidity is lowered, and an aromatic polycarbonate resin excellent in target melting characteristics cannot be produced.

Examples of the alkali metal compound include inorganic alkali metal compounds such as alkali metal hydroxides, carbonates and hydrogencarbonate compounds; organic alkali metal compounds such as salts with alkali metal alcohols, phenols and organic carboxylic acids. It is done. Here, as an alkali metal, lithium, sodium, potassium, rubidium, cesium etc. are mentioned, for example.
Among these alkali metal compounds, cesium compounds are preferable, and cesium carbonate, cesium hydrogen carbonate, and cesium hydroxide are particularly preferable.

  Examples of the alkaline earth metal compound include inorganic alkaline earth metal compounds such as alkaline earth metal hydroxides and carbonates; alkaline earth metal alcohols, phenols, salts with organic carboxylic acids, and the like. It is done. Here, examples of the alkaline earth metal include calcium, strontium, barium and the like.

  Examples of the beryllium compound and the magnesium compound include inorganic metal compounds such as hydroxides and carbonates of the metals; salts of the metals with alcohols, phenols, and organic carboxylic acids.

  Examples of basic boron compounds include sodium salts, potassium salts, lithium salts, calcium salts, magnesium salts, barium salts, strontium salts, and the like of boron compounds. Here, as the boron compound, for example, tetramethylboron, tetraethylboron, tetrapropylboron, tetrabutylboron, trimethylethylboron, trimethylbenzylboron, trimethylphenylboron, triethylmethylboron, triethylbenzylboron, triethylphenylboron, tributyl Examples include benzylboron, tributylphenylboron, tetraphenylboron, benzyltriphenylboron, methyltriphenylboron, and butyltriphenylboron.

  Examples of the basic phosphorus compound include trivalent phosphine compounds such as triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, and tributylphosphine, or derivatives thereof. And quaternary phosphonium salts.

  Examples of the basic ammonium compound include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide, Triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide Sid, butyl triphenyl ammonium hydroxide, and the like.

  Examples of the amine compound include 4-aminopyridine, 2-aminopyridine, N, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2 -Dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole, aminoquinoline and the like.

<Manufacturing process of polycarbonate resin>
Next, a specific manufacturing process of the polycarbonate resin to which the manufacturing method of the present invention is applied will be described.
The production process of the polycarbonate resin is to prepare a raw material mixed melt of a dihydroxy compound and a carbonic acid diester as raw materials (original tone process), and the raw material mixed melt is melted in the presence of a transesterification catalyst in a molten state. It is carried out by carrying out polycondensation reaction in multiple stages using a reaction vessel (polycondensation step). The reaction system may be any of a batch system, a continuous system, or a combination of a batch system and a continuous system. As the reaction tank, a plurality of vertical stirring reaction tanks and, if necessary, at least one horizontal stirring reaction tank subsequent thereto are used. Usually, these reaction tanks are installed in series and processed continuously.
After the polycondensation process, the reaction is stopped, the unreacted raw materials and reaction byproducts in the polycondensation reaction liquid are devolatilized and removed, the process of adding a thermal stabilizer, mold release agent, colorant, etc., polycarbonate resin You may add suitably the process etc. which form in a predetermined particle size.
Next, each process of the manufacturing method will be described.

(Primary process)
The dihydroxy compound and carbonic acid diester compound used as the raw material for the polycarbonate resin are usually raw materials using a batch, semi-batch or continuous stirring tank type apparatus in an inert gas atmosphere such as nitrogen or argon. Prepared as a mixed melt. For example, when bisphenol A is used as the dihydroxy compound and diphenyl carbonate is used as the carbonic acid diester compound, the melt mixing temperature is usually selected from the range of 120 ° C. to 180 ° C., preferably 125 ° C. to 160 ° C.
Hereinafter, the case where 2,2-bis (4-hydroxy-3-methylphenyl) propane (bisphenol A) is used as a dihydroxy compound and diphenyl carbonate is used as a raw material as a carbonic acid diester compound will be described as an example.
At this time, the ratio of the dihydroxy compound and the carbonic acid diester compound is adjusted so that the carbonic acid diester compound becomes excessive. The carbonic acid diester compound is usually 1.01 mol to 1.30 mol with respect to 1 mol of the dihydroxy compound. Preferably, it is adjusted to a ratio of 1.02 mol to 1.20 mol.

(Polycondensation process)
The polycondensation by the transesterification reaction between the dihydroxy compound and the carbonic acid diester compound is usually carried out continuously in a multistage system of two or more stages, preferably 3 to 7 stages. Specific reaction conditions for each stage are temperature: 150 ° C. to 320 ° C., pressure: normal pressure to 0.01 Torr (1.3 Pa), and average residence time: 5 minutes to 150 minutes.
In each multi-stage reaction tank, in order to more effectively remove aromatic monohydroxy compounds such as phenol as a by-product from the system as the polycondensation reaction proceeds, the temperature is increased stepwise in the above reaction conditions. Set to a higher vacuum.

When the polycondensation step is performed in a multistage manner, usually, a plurality of reaction vessels including a vertical stirring reaction vessel are provided to increase the average molecular weight of the polycarbonate resin. The reaction tank is usually installed in 2 to 6 groups, preferably 4 to 5 groups.
Here, as a reaction tank, for example, a stirring tank type reaction tank, a thin film reaction tank, a centrifugal thin film evaporation reaction tank, a surface renewal type biaxial kneading reaction tank, a biaxial horizontal type stirring reaction tank, a wet wall reaction tank, a free tank A perforated plate type reaction vessel that polycondenses while dropping, a perforated plate type reaction vessel with wire that polycondenses while dropping along a wire, and the like are used.

  The types of stirring blades in the vertical stirring reaction tank include, for example, turbine blades, paddle blades, fiddler blades, anchor blades, full zone blades (manufactured by Shinko Environmental Solution Co., Ltd.), Sun Meller blades (manufactured by Mitsubishi Heavy Industries, Ltd.), Max blend blades (manufactured by Sumitomo Heavy Industries, Ltd.), helical ribbon blades, twisted lattice blades (manufactured by Hitachi Plant Technology Co., Ltd.), and the like.

  Moreover, a horizontal stirring reaction tank means that the rotating shaft of a stirring blade is a horizontal type (horizontal direction). As a stirring blade of a horizontal stirring reaction tank, for example, a uniaxial stirring blade such as a disk type or a paddle type, HVR, SCR, N-SCR (manufactured by Mitsubishi Heavy Industries, Ltd.), Vivolak (Sumitomo Heavy Industries, Ltd.) )), Or biaxial stirring blades such as spectacle blades and lattice blades (manufactured by Hitachi Plant Technology Co., Ltd.).

  In addition, the transesterification catalyst used for the polycondensation of a dihydroxy compound and a carbonic acid diester compound may usually be prepared in advance as an aqueous solution. The concentration of the catalyst aqueous solution is not particularly limited, and is adjusted to an arbitrary concentration according to the solubility of the catalyst in water. Moreover, it can replace with water and other solvents, such as acetone, alcohol, toluene, and phenol, can also be selected.

The properties of water used for dissolving the catalyst are not particularly limited as long as the type and concentration of impurities contained are constant, but usually distilled water, deionized water, and the like are preferably used.
The polycarbonate resin obtained in the polymerization step is usually sent to a twin-screw extruder while in a molten state, and is cut into pellets by a cutter as a strand through a die.

Furthermore, the present invention provides a polycarbonate resin obtained from a dihydroxy compound containing a compound represented by the general formula (1) as a main component and a carbonate-forming compound, wherein the dihydroxy compound is represented by the general formula (2). The present invention relates to a polycarbonate resin in which the content of the obtained compound is 100 ppm or less, preferably 50 ppm or less, and the initial hue (YI) of the obtained polycarbonate resin is 2.0 or less, preferably 1.5 or less.
Furthermore, the present invention provides a polycarbonate resin obtained from a dihydroxy compound containing a compound represented by the general formula (1) as a main component and a carbonate-forming compound, wherein the dihydroxy compound is represented by the general formula (2). The present invention relates to a polycarbonate resin in which the content of the compound to be produced is 100 ppm or less, preferably 50 ppm or less, and the hue change value (ΔYI) during heat retention is 0.5 or less, preferably 0.3 or less.
These polycarbonate resins are produced by the interface method or the melting method described above.
The polycarbonate resin obtained by the production method according to the present invention is a polycarbonate resin excellent in color tone having a small initial hue and little hue change due to heat retention.

  Hereinafter, the present invention will be described more specifically based on examples. In addition, this invention is not limited to a following example, unless it deviates from the summary. The obtained polycarbonate was analyzed by the following measuring method.

(1) Content of compounds represented by general formulas (2), (3) and (4) in dihydroxy compound A methanol solution of dihydroxy compound (dihydroxy compound concentration: 10% by weight) is subjected to liquid chromatography (apparatus: manufactured by Agilent) 1100, column: YMC Pack ODS-AM 4.6 mm ID × 75 mm L, column temperature: 40 ° C., mobile phase: A solution 0.05% trifluoroacetic acid aqueous solution, B solution methanol Gradient condition: 0 min (B = 40%) → 25 min (B = 95%) → 40 min (B = 95%), flow rate: 1.0 ml / min, detector: UV 280 nm, injection amount: 10 μl).
Each compound was identified using Agilent LC-MS (Agilent-1100) and JEOL NMR (AL-400). The content of each compound was shown as a monomer conversion value based on a calibration curve of the monomer main component.

(2) Intrinsic viscosity [η] (dl / g)
The polymer was dissolved in methylene chloride (concentration 6.0 g / L) and measured at a temperature of 20 ° C. using an Ubbelohde viscometer.

(3) Terminal OH group concentration Colorimetric determination was performed by the titanium tetrachloride / acetic acid method (Makromol. Chem. 88 215 (1965)).

(4) Residual chloroformate group concentration (CF)
1.0 g of the polymer was dissolved in 20 ml of methylene chloride, and 2 ml of a 1% by weight methylene chloride solution of 4- (p-nitrobenzyl) pyridine (Wako Pure Chemicals, reagent grade) was added to develop the color, and a spectrophotometer (Hitachi ( Absorbance at a wavelength of 440 nm was measured using “330 type” manufactured by the same company. Separately, the extinction coefficient was determined using a methylene chloride solution of phenyl chloroformate, and the residual chloroformate (CF) group concentration in the sample was quantified.

(5) Hue 1) Molding of sample plate:
After the polymer was dried at 120 ° C. for 5 hours, it was plasticized at 300 ° C. using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., product name FS80S-12ASE), and then retained in the cylinder for 15 seconds. Sample plates of 2 mm and 60 mm square were formed. A sample plate was also molded after the plasticization with a residence time in the cylinder of 5 minutes.
2) Hue measurement:
About these sample boards, the hue (YI value) was measured using the color difference meter (the Suga Test Instruments Co., Ltd. product name SM-4-CH). Of the measured values, the value of 15-second retention (initial hue: YI) is small, indicating that the color tone during steady molding is good, and the difference between the YI values of 15-second retention and 5-minute retention (heat retention) A small hue change value of ΔYI) indicates that the thermal stability at high temperature is good.

"Example 1"
A commercially available product (manufactured by Seachem Co., Ltd.) was purified by distillation (stage number 50, reflux ratio 10) from orthocresol (2,6-xylenol content: 900 ppm), and purified orthocresol-3 (2,6) shown in Table 1 -The content of xylenol was 2 ppm). Mercaptoacetic acid as a catalyst was added to this purified product of orthocresol-3 and acetone, and the mixture was heated to 60 ° C. and stirred for 10 hours while blowing hydrogen chloride gas. The produced crystal was washed four times with warm water to obtain a crude product (purity 92.6%) of 2,2-bis (4-hydroxy-3-methylphenyl) propane.
Next, this crude product was dissolved in methanol, and toluene was added and mixed. Thereafter, the whole amount of methanol was distilled off under reduced pressure of 10 mmHg to precipitate as white crystals of 2,2-bis (4-hydroxy-3-methylphenyl) propane. The obtained crystals were separated by filtration and dried, and the results of measuring the content of the compounds represented by the above general formulas (2) to (4) are shown in Table 2. Note that almost all of the compounds represented by the general formula (2) are compounds represented by the above formula (2A) (others are below the detection limit), and almost all of the compounds represented by the general formula (3) Compounds represented by the above formula (3A) (others are below the detection limit) and almost all of the compounds represented by the general formula (4) are represented by the above formula (4A) or the above formula (4B). (Others were below the detection limit).
This 2,2-bis (4-hydroxy-3-methylphenyl) propane (hereinafter abbreviated as “BPC”) 13.80 kg / hr, sodium hydroxide (NaOH) 5.8 kg / hr and water 93.5 kg / hr In the presence of hydrosulfite 0.017 kg / hour, an aqueous phase cooled to 25 ° C. after dissolving at 35 ° C. and an organic phase of 61.9 kg / hour methylene chloride cooled to 5 ° C. each had an inner diameter of 6 mm, In a Teflon pipe reactor having an inner diameter of 6 mm and a length of 34 m connected to the Teflon pipe having an outer diameter of 8 mm, it was brought into contact with 7.2 kg / hour of liquefied phosgene cooled to 0 ° C. separately introduced here. . The raw material (BPC / sodium hydroxide solution) was subjected to phosgenation and oligomerization while flowing through phosgene and the pipe reactor at a linear velocity of 1.7 m / second for 20 seconds. At this time, the reaction temperature reached a tower top temperature of 60 ° C. in the heat insulation system. The temperature of the reaction product was adjusted by external cooling to 35 ° C. before entering the next oligomerization tank. In the oligomerization, triethylamine 5 g / hour as a catalyst (0.9 × 10 ⁻³ mole relative to 1 mole of BPC) and pt-butylphenol 0.12 kg / hour as a molecular weight regulator, these are respectively supplied to the oligomerization tank. Introduced.
The oligomerized emulsion thus obtained from the pipe reactor is further introduced into a reaction vessel with a stirrer having an internal volume of 50 liters and stirred at 30 ° C. in a nitrogen gas (N ₂ ) atmosphere to be oligomerized. Then, after completely consuming the unreacted sodium salt of BPC (BPC-Na) present in the aqueous phase, the aqueous phase and the oil phase were allowed to stand and separate to obtain an oligomeric methylene chloride solution.
Of the above methylene chloride solution of oligomer, 23 kg was charged into a reaction vessel equipped with a 70 liter Faudler vane, and 10 kg of methylene chloride for dilution was added thereto. Further, 2.2 kg of 25 wt% aqueous sodium hydroxide solution and 6 kg of water were added. And 2.2 g of triethylamine (1.1 × 10 ⁻³ mol relative to 1 mol of BPC) were added, and the mixture was stirred at 30 ° C. in a nitrogen gas atmosphere and subjected to a polycondensation reaction for 60 minutes to obtain a polycarbonate resin.
To this reaction solution, 30 kg of methylene chloride and 7 kg of water were added and stirred for 20 minutes. Then, stirring was stopped and the aqueous phase and the organic phase were separated. To the separated organic phase, 20 kg of 0.1N hydrochloric acid was added and stirred for 15 minutes to extract triethylamine and a small amount of remaining alkali component, and then stirring was stopped to separate the aqueous phase and the organic phase. Further, 20 kg of pure water was added to the separated organic phase, and the mixture was stirred for 15 minutes, and then the stirring was stopped to separate the aqueous phase and the organic phase. This operation was repeated (three times) until no chlorine ions were detected in the extracted waste water. The obtained purified polycarbonate solution was pulverized by feeding into 40 ° C. warm water, and dried to obtain granular powder (flakes).
The obtained polycarbonate flakes were fed into a twin-screw extruder and cut with a cutter as a strand through a die to obtain pellets. The physical properties of the obtained polycarbonate resin are also shown in Table 2.

"Example 2"
6.55 mol (1.68 kg) of BPC obtained in Example 1 and 6.73 mol (1.44 kg) of diphenyl carbonate were placed in a SUS reactor equipped with a stirrer and a distillation condenser with an internal volume of 10 liters. The reactor inside the reactor was replaced with nitrogen gas, and then heated to 220 ° C. in a nitrogen gas atmosphere over 30 minutes. Subsequently, cesium carbonate (Cs ₂ CO ₃ ) was added as an ester exchange reaction catalyst under stirring and in a molten state in an aqueous solution so as to be 1.5 × 10 ⁻⁶ mol with respect to 1 mol of BPC (as Cs ₂ CO ₃ 3.20 mg) The mixture was stirred for 30 minutes at 220 ° C. in a nitrogen gas atmosphere. Next, the pressure was reduced to 100 Torr (13.3 kPa) over 40 minutes at the same temperature, and the reaction was carried out for 100 minutes to distill phenol. Next, the temperature was raised to 280 ° C. over 60 minutes and the pressure was reduced to 3 Torr (400 Pa) to distill almost the entire phenol distillation theoretical amount. Next, at the same temperature, the reaction (60 minutes) was performed until the target stirring power value was reached at less than 1 Torr (133 Pa), thereby completing the polycondensation reaction.
Next, this polymer was fed into a twin-screw extruder in a molten state, and butyl p-toluenesulfonate (4 times molar amount relative to cesium carbonate used as a catalyst) was supplied from the first supply port and kneaded. A pellet was obtained by cutting with a cutter as a strand through a die.
The results of the obtained polycarbonate resin are also shown in Table 2.

"Example 3"
1,1-bis (4-hydroxy-3-methylphenyl) cyclohexane (abbreviated as “Bis-OCZ”) was synthesized as follows using the purified orthocresol product-3 of Example 1.
A three-necked round bottom flask equipped with a gas inlet, a dropping funnel, a thermometer and a reflux condenser was purged with nitrogen and preheated to about 45 ° C. Next, after o-cresol was charged into the reactor and stirring was started, dry hydrogen chloride gas was introduced into the reaction mixture and bubbled, and stirring was performed by gas dispersion until the atmosphere in the reactor appeared cloudy. This mixture was treated dropwise with cyclohexanone with continued stirring for about 2 hours. The temperature of the reaction solution was maintained at about 60 ° C. The progress of the reaction was monitored by following the disappearance of cyclohexanone using a gas chromatograph. After stirring for about 24 hours, the reaction mixture was sparged with nitrogen for about 1.5 hours to remove hydrogen chloride vapor. The reaction mixture was cooled to room temperature and filtered using a funnel. The cake was dried and transferred to a round bottom flask and slurried with dichloromethane over about 40 minutes with stirring. The resulting suspension was filtered and the filter cake was washed with dichloromethane, sucked dry and then vacuum dried at 90 ° C. Table 2 shows the contents of the compounds represented by the general formulas (2) to (4) in the obtained Bis-OCZ. In addition, almost all of the compound represented by the general formula (2) is a compound represented by the above formula (2B) (others are below the detection limit), and the content thereof is 18 ppm, represented by the general formula (3). Almost all of the compounds represented by the above formula (3B) (others are below the detection limit), almost all of the compounds represented by the general formula (4) are represented by the above formula (4C) or the above formula (4D). ) (Others were below the detection limit).
The same operation as in Example 1 was conducted except that this Bis-OCZ was used at 15.5 kg / hour.
The physical properties of the obtained polycarbonate resin are also shown in Table 2.

Example 4
The distillation purification conditions of the commercial product orthocresol in Example 1 were changed to obtain a purified product of orthocresol-2 (content of 2,6-xylenol was 136 ppm) shown in Table 1. In Example 3, Bis-OCZ was synthesized using Orthocresol purified product-2 instead of Orthocresol purified product-3.
In Example 2, 1.93 kg of this synthesized Bis-OCZ was used instead of BPC, and cesium carbonate (Cs ₂ CO ₃ ) was 1.0 × 10 ⁻⁶ mol with respect to 1 mol of Bis-OCZ. The procedure was the same as in Example 1 except for the change.
The physical properties of the obtained polycarbonate resin are also shown in Table 2.

"Comparative Example 1"
In Example 1, BPC was synthesize | combined using the commercial product orthoxazole (content of 2, 6- xylenol is 900 ppm), and it implemented like Example 1 except having used this BPC as a raw material. Table 2 shows the contents of the compounds represented by the general formulas (2) to (4) in the BPC. Note that almost all of the compounds represented by the general formula (2) are compounds represented by the above formula (2A) (others are below the detection limit), and almost all of the compounds represented by the general formula (3) Compounds represented by the above formula (3A) (others are below the detection limit) and almost all of the compounds represented by the general formula (4) are represented by the above formula (4A) or the above formula (4B). (Others were below the detection limit).
The physical properties of the obtained polycarbonate resin are also shown in Table 2.

"Comparative Example 2"
The distillation purification conditions of the commercial product orthocresol in Example 1 were changed to obtain purified orthocresol-1 (content of 2,6-xylenol was 511 ppm) shown in Table 1. The same procedure as in Example 1 was performed except that BPC obtained from this orthocresol purified product-1 was used. Table 2 shows the contents of the compounds represented by the general formulas (2) to (4) in the BPC. Note that almost all of the compounds represented by the general formula (2) are compounds represented by the above formula (2A) (others are below the detection limit), and almost all of the compounds represented by the general formula (3) Compounds represented by the above formula (3A) (others are below the detection limit) and almost all of the compounds represented by the general formula (4) are represented by the above formula (4A) or the above formula (4B). (Others were below the detection limit).
The physical properties of the obtained polycarbonate resin are also shown in Table 2.

“Comparative Example 3”
In Comparative Example 2, the same procedure as in Comparative Example 2 was performed, except that the compound represented by the formula (3A) in BPC was fractionated by liquid chromatography and adjusted to the content shown in Table 2.
The physical properties of the obtained polycarbonate resin are also shown in Table 2.

“Comparative Example 4”
In Example 3, it carried out like Example 3 except having used Bis-OCZ obtained from a commercial product orthocresol. Table 2 shows the contents of the compounds represented by the general formulas (2) to (4) in the obtained Bis-OCZ. In addition, almost all of the compound represented by the general formula (2) is a compound represented by the above formula (2B) (others are below the detection limit), and the content thereof is 18 ppm, represented by the general formula (3). Almost all of the compounds represented by the above formula (3B) (others are below the detection limit), almost all of the compounds represented by the general formula (4) are represented by the above formula (4C) or the above formula (4D). ) (Others were below the detection limit).
The physical properties of the obtained polycarbonate resin are also shown in Table 2.

  ADVANTAGE OF THE INVENTION According to this invention, the polycarbonate resin with favorable hue and thermal stability and its manufacturing method are provided by regulating the specific impurity dihydroxy compound contained in the raw material dihydroxy compound.

Claims (8)

A method for producing a polycarbonate resin obtained by polymerizing a dihydroxy compound containing a compound represented by the following general formula (1) as a main component and a carbonate-forming compound, wherein the following general formula (2) The content of the compound represented by this is 100 ppm or less, The manufacturing method of polycarbonate resin characterized by the above-mentioned.

(In the general formula (1), R ₁ and R ₂ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single group. And represents a bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)

(In the general formula (2), R ₁ , R ₂ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group; ₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group. Represents a substituted or unsubstituted sulfur atom or an oxygen atom.) Content of the compound represented by the following general formula (3) in the said dihydroxy compound is 2000 ppm or less, The manufacturing method of polycarbonate resin of Claim 1 characterized by the above-mentioned.

(In General Formula (3), R ₁ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or It represents an unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.) Content of the compound represented by following General formula (4) in the said dihydroxy compound is 200 ppm or less, The manufacturing method of the polycarbonate resin of Claim 1 or 2 characterized by the above-mentioned.

(In General Formula (4), R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted group. Represents an aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom, provided that the bonding positions of two hydroxyl groups in the general formula (4) Except for the 4-position (para-position) to X on each phenyl ring.) The substituted or unsubstituted alkylidene group of X in the general formulas (1) to (4) is

The method for producing a polycarbonate resin according to any one of claims 1 to 3, wherein:
(R ₅ and R ₆ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and Z represents a substituted or unsubstituted aryl group. An alkylene group having 4 to 20 carbon atoms is shown.) The compound represented by the general formula (1) is produced using a compound represented by the following general formula (5) as a raw material. In the compound represented by the following general formula (5), the following general formula ( The method for producing a polycarbonate resin according to any one of claims 1 to 4, wherein the content of the compound represented by 6) is 500 ppm or less.

(In the general formula (5), R ₁ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group.)

(In General Formula (6), R ₁ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group.)   The compound represented by the general formula (1) is 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-methylphenyl) cyclohexane, 1,1 -At least one selected from the group consisting of bis (4-hydroxy-3-methylphenyl) -3,5,5-trimethylcyclohexane and 1,1-bis (4-hydroxy-3-methylphenyl) cyclododecane The method for producing a polycarbonate resin according to any one of claims 1 to 5, wherein: A polycarbonate resin obtained by using a dihydroxy compound containing a compound represented by the following general formula (1) as a main component and a carbonate-forming compound, the compound containing the compound represented by the following general formula (2) in the dihydroxy compound A polycarbonate resin, characterized in that the amount is 100 ppm or less, and the initial hue (YI) of the obtained polycarbonate resin is 2.0 or less.

(In the general formula (1), R ₁ and R ₂ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single group. And represents a bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)

(In the general formula (2), R ₁ , R ₂ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group; ₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, A substituted or unsubstituted sulfur atom or an oxygen atom is shown.) A polycarbonate resin obtained by using a dihydroxy compound containing a compound represented by the following general formula (1) as a main component and a carbonate-forming compound, the compound containing the compound represented by the following general formula (2) in the dihydroxy compound A polycarbonate resin characterized by having an amount of 100 ppm or less and a hue change value (ΔYI) at the time of heat retention of the obtained polycarbonate resin being 0.5 or less.

(In the general formula (1), R ₁ and R ₂ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group, and X represents a single group. And represents a bond, a carbonyl group, a substituted or unsubstituted alkylidene group, a substituted or unsubstituted sulfur atom, or an oxygen atom.)

(In the general formula (2), R ₁ , R ₂ and R ₃ each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group; ₄ represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group, and X represents a single bond, a carbonyl group, a substituted or unsubstituted alkylidene group, A substituted or unsubstituted sulfur atom or an oxygen atom is shown.)