JP2020147536A - Bisphenol composition and method for producing polycarbonate resin - Google Patents

Abstract

To provide a bisphenol composition which enables production of a polycarbonate resin that is excellent in a methanol dissolution color, a fusion color difference, thermal color tone stability and thermal decomposition stability and has good color tone can be produced.SOLUTION: A bisphenol composition has 95 mass% or more of bisphenol, and 1 mass ppm or more of 2,2'-bi[1-hydroxy-4-(4-hydroxy-3-methylphenyl)dimethylmethyl]-6-methylphenyl]. The bisphenol is preferably 2,2-bis(4-hydroxy-3-methylphenyl)propane. A method for producing a polycarbonate resin uses the bisphenol composition.SELECTED DRAWING: None

Description

The present invention relates to a bisphenol composition and a method for producing a polycarbonate resin using the bisphenol composition.
The bisphenol composition of the present invention is useful as a resin raw material such as a polycarbonate resin, an epoxy resin, and an aromatic polyester resin, and as an additive for a curing agent, a color developer, a fading inhibitor, and other bactericidal agents and antibacterial and antifungal agents. Is.

Bisphenol is useful as a raw material for polymer materials such as polycarbonate resins, epoxy resins, and aromatic polyester resins. As typical bisphenols, for example, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane and the like are known (Patent Documents 1 and 2). ).

Japanese Unexamined Patent Publication No. 62-138443 Japanese Unexamined Patent Publication No. 2014-40376

Polycarbonate resin, which is a typical use of bisphenol, is required to be colorless and transparent. The color tone of the polycarbonate resin is greatly affected by the color tone of the raw material. Therefore, the color tone of bisphenol as a raw material is also required to be colorless (here, since it is difficult to directly quantify the color of bisphenol, in the present invention, bisphenol is dissolved in methanol to quantify the color difference. This color tone is referred to as "methanol-dissolved color"). Further, in the production of the polycarbonate resin, particularly in the melting method, bisphenol is melted to produce the polycarbonate resin, so that the polycarbonate resin is exposed to a high temperature. Therefore, the stability of the thermal color tone of bisphenol is also required (in the present invention, this color tone is referred to as "melt color difference"). Furthermore, since the polymerization reaction is carried out after the bisphenol is melted, thermal color tone stability before the start of polymerization is also required (in the present invention, this color tone is referred to as "thermal color tone stability"). Further, if bisphenol is thermally decomposed before the start of polymerization, the amount of substance of bisphenol decreases, and the substance amount ratio with the raw material diphenyl carbonate deviates from the predetermined substance amount ratio, so that the desired molecular weight is reached. Since a polycarbonate resin cannot be obtained, the thermal stability of bisphenol is also required (in the present invention, this stability is referred to as "pyrolysis stability").

As for the polycarbonate resin, there is a demand for a polycarbonate resin having a molecular weight as designed and having a good color tone. Therefore, in order to produce such a polycarbonate resin, bisphenol as a raw material is required to have excellent methanol-dissolved color, melt color difference, and thermal color tone stability, and also have excellent thermal decomposition stability. There is.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a bisphenol composition having good methanol dissolution color, melt color difference, thermal color tone stability, and thermal decomposition stability. Another object of the present invention is to provide a polycarbonate resin having an excellent color tone by using this bisphenol composition.

As a result of diligent studies to solve the above problems, the present inventors have found that a bisphenol composition containing a specific compound in a predetermined ratio has methanol-dissolved color, melt color difference, thermal color stability, and thermal decomposition stability. It has been found that a polycarbonate resin having an excellent color tone can be produced by using this bisphenol composition, and the present invention has been completed.
That is, the gist of the present invention lies in the following [1] to [6].

[1] Contains 95% by mass or more of bisphenol and 1% by mass or more of 2,2'-bi [1-hydroxy-4- (4-hydroxy-3-methylphenyl) dimethylmethyl] -6-methylphenyl] Bisphenol composition.

[2] The bisphenol composition according to [1], which contains 2,2'-bi [1-hydroxy-4- (4-hydroxy-3-methylphenyl) dimethylmethyl] -6-methylphenyl] in an amount of 300 mass ppm or less. object.

[3] The bisphenol composition according to [1] or [2], wherein the bisphenol is 2,2-bis (4-hydroxy-3-methylphenyl) propane.

[4] When 2,2'-bi [1-hydroxy-4- (4-hydroxy-3-methylphenyl) dimethylmethyl] -6-methylphenyl] is produced as a by-product in the production of bisphenol [1] to [ 3] The method for producing a bisphenol composition according to any one of.

[5] A method for producing a polycarbonate resin using the bisphenol composition according to any one of [1] to [3].

[6] The method for producing a polycarbonate resin according to [5], which produces a polycarbonate resin having a viscosity average molecular weight of 15,000 or more and 35,000 or less.

According to the present invention, a bisphenol composition having good methanol dissolution color, melt color difference, thermal color tone stability, and thermal decomposition stability is provided by containing a specific compound in a predetermined ratio. In addition, this bisphenol composition can be used to produce a polycarbonate resin having an excellent color tone.

The embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is an example of the embodiments of the present invention, and the present invention is described below as long as the gist of the present invention is not exceeded. It is not limited to.
In addition, when the expression "-" is used in this specification, it shall be used as an expression including numerical values or physical property values before and after the expression.

[Bisphenol composition]
The bisphenol composition of the present invention contains 95% by mass or more of bisphenol and is represented by the following structural formula (I), 2,2'-bi [1-hydroxy-4- (4-hydroxy-3-methylphenyl)). A bisphenol composition containing 1% by mass or more of [dimethylmethyl] -6-methylphenyl] (hereinafter referred to as "bisbisphenol C").

The content of bisphenol C in the bisphenol composition of the present invention is preferably 5 mass ppm or more, preferably 500 mass ppm or less, and more preferably 300 mass ppm or less.

If the content of bisphenol C in the bisphenol composition is less than the above lower limit, a bisphenol composition having good methanol dissolution color, melt color difference, thermal color tone stability, and thermal decomposition stability cannot be obtained. Further, if the content of bisphenol C in the bisphenol composition exceeds the above upper limit, the molar ratio with diphenyl carbonate may shift when the polycarbonate resin is produced, which may affect the polymerization reaction. In addition, the brittleness (izod) of the polycarbonate resin can be reduced, and 2,2-bis (4-hydroxy-3-methylphenyl) propane or 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane can be used. There is a risk of reducing the high surface hardness peculiar to polycarbonate resin containing structural units derived from.
Detection and quantification of bisphenol C can be performed using a standard reverse phase column for high speed analysis with a particle size of 3 μm.

<Bisphenol>
The bisphenol contained in the bisphenol composition of the present invention is usually a compound represented by the following general formula (1).

R ^{1 to} R ⁶ in the general formula (1) are synonymous with R ^{1 to} R ⁶ in the general formulas (3) and (4) described later, and suitable examples and specific examples thereof are described in the general formula described later. It is as explained in (3) and (4).

Specific examples of the bisphenol represented by the general formula (1) include 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, and 2, 2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 1,1-bis (4-hydroxy-3-methylphenyl) cyclohexane, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene , 3,3-bis (4-hydroxyphenyl) pentane, 3,3-bis (4-hydroxy-3-methylphenyl) pentane, 2,2-bis (4-hydroxyphenyl) pentane, 2,2-bis ( 4-Hydroxy-3-methylphenyl) pentane, 3,3-bis (4-hydroxyphenyl) heptane, 3,3-bis (4-hydroxy-3-methylphenyl) heptane, 2,2-bis (4-hydroxy) Phenyl) heptane, 2,2-bis (4-hydroxy-3-methylphenyl) heptane, 4,4-bis (4-hydroxyphenyl) heptane, 4,4-bis (4-hydroxy-3-methylphenyl) heptane However, it is not limited to these.

Among these, the bisphenol contained in the bisphenol composition of the present invention includes 2,2-bis (4-hydroxy-3-methylphenyl) propane or 2,2-bis (4-hydroxy-3,5-dimethylphenyl). Propane is preferable, and 2,2-bis (4-hydroxy-3-methylphenyl) propane (bisphenol C) is particularly preferable.

The bisphenol composition of the present invention contains such bisphenol in an amount of 95% by mass or more, preferably 99% by mass or more, and more preferably 99.5% by mass or more. If the content of bisphenol is less than the above lower limit, it is not preferable for use as bisphenol. The upper limit of the content of bisphenol in the bisphenol composition of the present invention is to secure the content of bisphenol C, from the viewpoint of production cost, etc., to adjust the ratio of the physical property to diphenyl carbonate in the production reaction of the polycarbonate resin, the surface hardness, and the like. From the viewpoint of mechanical properties of the polycarbonate resin such as brittleness, it is usually about 99.9% by mass.
Detection and quantification of bisphenol can be performed using standard reverse phase columns for fast analysis.

<Methanol-dissolved color of bisphenol composition>
The methanol-dissolved color of the bisphenol composition is used to evaluate the color tone of the bisphenol composition at room temperature. The lower the number of Hazen colors of the methanol-dissolved color of the bisphenol composition, the better the color tone of the bisphenol composition (closer to white). Examples of the cause of deteriorating the methanol-dissolved color of the bisphenol composition include contamination of organic coloring components and metals.
The methanol-dissolved color of the bisphenol composition is measured at room temperature (about 20 ° C.) after the bisphenol composition is dissolved in methanol to prepare a uniform solution. Examples of the measuring method include a method of visually comparing with a standard solution having a Hazen color number, or a method of measuring the Hazen color number using a color difference meter such as "SE6000" manufactured by Nippon Denshoku Kogyo Co., Ltd. The mass ratio of the solvent methanol and bisphenol used here to the solvent is preferably selected as appropriate depending on the type of bisphenol.
The number of Hazen colors of the methanol-dissolved color of the bisphenol composition is preferably 20 or less, more preferably 10 or less, and particularly preferably 5 or less.

<Melted color difference of bisphenol composition>
The melt color difference of the bisphenol composition is used to evaluate the color tone of the bisphenol composition at a temperature close to the polymerization temperature of polycarbonate. The measurement temperature of the melt color difference is the melting point of bisphenol + 50 ° C. The melt color difference of the bisphenol composition indicates that the lower the number of Hazen colors, the better the color tone of the bisphenol composition (closer to white). As a cause of exacerbating the melt color difference of the bisphenol composition, there are components that are colored by heating in addition to organic coloring components and metal contamination.
The melt color difference of the bisphenol composition is measured in advance by melting the bisphenol composition at a temperature close to the polymerization temperature and measuring the time at which the temperature is stable. Examples of the measuring method include a method of visually comparing with a standard solution having a Hazen color number, or a method of measuring the Hazen color number using a color difference meter such as "SE6000" manufactured by Nippon Denshoku Kogyo Co., Ltd.
The number of Hazen colors is preferably 40 or less, more preferably 30 or less, and particularly preferably 20 or less.

<Thermal color stability of bisphenol composition>
The thermal color stability of the bisphenol composition is used to evaluate the thermal stability of the color tone of the bisphenol composition by holding it at a temperature close to the polymerization temperature of polycarbonate for a predetermined time, similar to the melt color difference of the bisphenol composition. The measurement temperature of the thermal color stability of the bisphenol composition is the melting point of bisphenol + 50 ° C.
As for the thermal color stability of the bisphenol composition, the lower the number of Hazen colors, the better the thermal color stability of the bisphenol composition. Causes of deteriorating the thermal color stability of the bisphenol composition include, in addition to the mixing of organic coloring components and metals, components that are colored by heating and acidic substances and basic substances having a concentration of about several ppm.
The thermal color stability of the bisphenol composition is measured in advance by melting the bisphenol composition at a temperature close to the polymerization temperature and measuring the time at which the temperature is stable. The retention time for thermal color stability of the bisphenol composition is 4 hours. Examples of the measuring method include a method of visually comparing with a standard solution having a Hazen color number, or a method of measuring the Hazen color number using a color difference meter such as "SE6000" manufactured by Nippon Denshoku Kogyo Co., Ltd.
The number of Hazen colors is preferably 50 or less, more preferably 45 or less, and particularly preferably 35 or less.

<Pyrolysis stability of bisphenol composition>
Similar to the thermal color stability of the bisphenol composition, the thermal decomposition stability of the bisphenol composition is used to evaluate the thermal stability of the bisphenol composition by holding it at a temperature close to the polymerization temperature of polycarbonate for a predetermined time. The preferred measurement temperature for the thermal decomposition stability of the bisphenol composition is the melting point of bisphenol + 50 ° C. The thermal decomposition stability of the bisphenol composition indicates that the smaller the amount of the decomposed product produced, the more stable the bisphenol composition is. The decomposition product in the thermal decomposition stability of the bisphenol composition depends on the type of bisphenol, but an aromatic alcohol which is a raw material of the bisphenol composition or an adduct of a ketone or an aldehyde which is a raw material of the aromatic alcohol is used. Can be mentioned. Causes of deteriorating the thermal decomposition stability of the bisphenol composition include, in addition to the mixing of organic coloring components and metals, components that are colored by heating and acidic substances and basic substances having a concentration of about several ppm.
Detection and quantification of degradation products of bisphenol compositions can be performed using standard reverse phase columns for fast analysis.
The amount of isopropenyl cresol produced as a decomposition product of the bisphenol composition as measured in Examples described later is preferably 200 mass ppm or less.

The methanol-dissolved color of the bisphenol composition is a method for evaluating the color tone of the bisphenol composition itself. When the bisphenol composition is the final product, the bisphenol composition having a good methanol-dissolved color is important. Further, since the polycarbonate resin inherits the color tone of the raw material, a bisphenol composition having a good color tone is important for the polycarbonate resin that is required to be colorless and transparent.
Further, in the melt polymerization method, which is one of the methods for producing a polycarbonate resin, since the polymerization reaction is carried out at a high temperature, the color tone of the bisphenol composition at the time of melting (melt color difference of the bisphenol composition) and the bisphenol composition in the molten state. The color stability of the object (thermal color stability of the bisphenol composition) is important.
Further, in the melt polymerization method, the bisphenol composition is kept in a molten state at a high temperature until the start of the polymerization reaction. In the melt polymerization method, when the bisphenol composition is decomposed at a high temperature, the substance amount ratio with diphenyl carbonate deviates from the predetermined substance amount ratio, and it is difficult to obtain a polycarbonate resin having polymerization reaction activity and a predetermined molecular weight. Become. Therefore, resistance to thermal decomposition (thermal decomposition stability of the bisphenol composition) is important.
In particular, in order to produce a polycarbonate resin having a predetermined molecular weight and a good color tone, the methanol-dissolved color of the bisphenol composition, the melt color difference of the bisphenol composition, the thermal color stability of the bisphenol composition, and the heat of the bisphenol composition Decomposition stability is important.

<Manufacturing method of bisphenol composition>
The method for producing the bisphenol composition of the present invention containing 95% by mass or more of bisphenol and containing bisphenol C in a predetermined ratio is not particularly limited, and examples thereof include the following methods.
(1) Method of adding a predetermined amount of bisbisphenol C to solid bisphenol (2) Method of adding a predetermined amount of bisbisphenol C to molten bisphenol (3) By-product of bisphenol C when producing bisphenol How to obtain a bisphenol product containing bisphenol C

In the methods (1) and (2) of adding bisphenol C to solid or melted bisphenol, it is necessary to prepare bisphenol C separately. Therefore, (3) bisphenol C in the reaction system for producing bisphenol. Is preferable, a method in which bisphenol C is contained in a bisphenol product in a predetermined ratio is preferable.

If the amount of bisphenol C produced as a by-product in the bisphenol reaction system is too large, the obtained bisphenol product is further purified by crystallization, suspension washing, sprinkling washing, etc., and the bisphenol contained in the bisphenol product is contained. By removing a part of C, it is possible to control so that a bisphenol product containing bisphenol C within the specified range of the present invention can be obtained.

<Method of obtaining bisphenol product containing bisphenol C>
As a method for producing bisphenol C together with bisphenol in a reaction system during the production of bisphenol to obtain a bisphenol product containing bisbisphenol C as the bisphenol composition of the present invention, a ketone or aldehyde and aromatic alcohol are used as an acid catalyst and thiol. A method of producing bisphenol by condensing in the presence of a co-catalyst can be mentioned, and according to this method, bisphenol C can be produced in the reaction system.
This method will be described below.

In this method, bisphenol is produced by condensing an aromatic alcohol with a ketone or aldehyde in the presence of an acid catalyst.
This bisphenol production reaction is carried out according to the reaction formula (2) shown below.

(In the formula, R ^{1 to} R ⁶ are synonymous with those in the general formula (1).)

(Aromatic alcohol)
The raw material aromatic alcohol used for producing bisphenol is usually a compound represented by the following general formula (3).

In the general formula (3), examples of R ^{1 to} R ⁴ include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, and an aryl group, respectively. The alkyl group, alkoxy group, aryl group and the like may be substituted or unsubstituted. Examples of R ^{1 to} R ⁴ include hydrogen atom, fluoro group, chloro group, bromo group, iodo group, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group and i-butyl group. , T-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group. , Methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, t-butoxy group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-Heptyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, Cycloheptyl group, cyclooctyl group, cyclododecyl group, benzyl group, phenyl group, tolyl group, 2,6-dimethylphenyl group and the like can be mentioned.

Of these, R ² and R ³ are preferably hydrogen atoms because the condensation reaction does not easily proceed if they are sterically bulky. ^Further, R 1 to R ⁴ is more preferably each independently a hydrogen atom or an alkyl ^group, R 1, ^{R 4} is each independently a hydrogen atom or an alkyl ^group, R 2, ^{R 3} is a hydrogen atom Is even more preferable.

Specific examples of the compound represented by the general formula (3) include phenol, cresol, xylenol, ethylphenol, propylphenol, butylphenol, methoxyphenol, ethoxyphenol, propoxyphenol, butoxyphenol, benzylphenol, and phenylphenol. Can be mentioned.

Among them, any one selected from the group consisting of phenol, cresol, and xylenol is preferable, cresol or xylenol is more preferable, and cresol is further preferable.

(Ketone or aldehyde)
The raw material ketone or aldehyde used for producing bisphenol is usually a compound represented by the following general formula (4).

In the general formula (4), examples of R ⁵ and R ⁶ include a hydrogen atom, an alkyl group, an alkoxy group, and an aryl group, respectively. The alkyl group, alkoxy group, aryl group and the like may be substituted or unsubstituted. For example, hydrogen atom, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group. , N-Heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, methoxy group, ethoxy group, n-propoxy group, i -Propoxy group, n-butoxy group, i-butoxy group, t-butoxy group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n -Nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclododecyl group, Examples thereof include a benzyl group, a phenyl group, a tolyl group, and a 2,6-dimethylphenyl group.

R ⁵ and R ⁶ may be bonded or crosslinked with each other between the two groups, or R ⁵ and R ⁶ may be bonded together with adjacent carbon atoms to contain a heteroatom. The alkylidene group may be formed. The cycloalkylidene group is a divalent group obtained by removing two hydrogen atoms from one carbon atom of cycloalkane.

The cycloalkylidene group and R ⁵ and R ⁶ are attached form together with the adjacent carbon atoms, for example, cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, 3,3,5-trimethyl Cyclohexylidene, cycloheptylidene, cyclooctylidene, cyclononylidene, cyclodecylidene, cycloundecylidene, cyclododecylidene, fluorenylidene, xanthonidene, thioxanthonidene and the like can be mentioned.

Specific examples of the compound represented by the general formula (4) include formaldehyde, acetaldehyde, propionaldehyde, butylaldehyde, pentylaldehyde, hexylaldehyde, heptylaldehyde, octylaldehyde, nonylaldehyde, decylaldehyde, and undecylaldehyde. Ketones such as dodecylaldehyde, acetone, butanone, pentanon, hexanone, heptanone, octanon, nonanone, decanone, undecanone, dodecanone, etc., benzaldehyde, phenylmethylketone, phenylethylketone, phenylpropylketone, cresylmethylketone, Arylalkyl Ketones such as Cresyl Ethyl Ketones, Cresylpropyl Ketones, Xylyl Methyl Ketones, Xylyl Ethyl Ketones, Xyrylpropyl Ketones, Cyclopropanone, Cyclobutanone, Cyclopentanone, Cyclohexanone, Cycloheptanone, Cyclooctanone, Cyclic alcan ketones such as cyclononanone, cyclodecanone, cycloundecanone, and cyclododecanone can be mentioned. Of these, acetone is preferable.

In the reaction of condensing an aromatic alcohol with a ketone or an aldehyde, if the molar ratio of the aromatic alcohol to the ketone or aldehyde is small, the amount of the ketone or aldehyde increases, but if it is large, the aromatic alcohol is lost unreacted. From these facts, the molar ratio of the aromatic alcohol to the ketone or aldehyde is preferably 1.5 or more, more preferably 1.6 or more, still more preferably 1.7 or more, and preferably 15 or less. , More preferably 10 or less, still more preferably 8 or less.

As a method for supplying ketones and aldehydes, a method of supplying them all at once and a method of supplying them in divided amounts can be used. The method of supplying the mixture is preferable.

(Acid catalyst)
Examples of the acid catalyst used for producing bisphenol include aromatic sulfonic acids such as sulfuric acid, hydrochloric acid, hydrogen chloride gas, phosphoric acid and p-toluenesulfonic acid, and aliphatic sulfonic acids such as methanesulfonic acid.

If the molar ratio of the acid catalyst to the ketone or aldehyde used for condensation ((number of moles of acid catalyst / number of moles of ketone) or (number of moles of acid catalyst / number of moles of aldehyde)) is small, as the condensation reaction progresses. The acid catalyst is diluted by the by-produced water and the reaction takes time. In addition, when the amount is large, the amount of ketones or aldehydes may increase. From these facts, the molar ratio of the acid catalyst to the ketone or aldehyde used for condensation is preferably 0.01 or more, more preferably 0.05 or more, still more preferably 0.1 or more. The upper limit thereof is preferably 10 or less, more preferably 8 or less, and further preferably 5 or less.

The acid catalyst shall be any one selected from the group consisting of aromatic sulfonic acids such as sulfuric acid, hydrochloric acid, hydrogen chloride gas, phosphoric acid and p-toluenesulfonic acid, and aliphatic sulfonic acids such as methanesulfonic acid. Is preferable.
If the molar ratio of hydrogen chloride to the ketone or aldehyde used in the reaction ((number of moles of hydrogen chloride / number of moles of ketone) or (number of moles of hydrogen chloride / number of moles of aldehyde)) is small, water produced as a by-product during the condensation reaction Hydrogen chloride is diluted by this, which requires a long reaction time. On the other hand, if the amount is large, the amount of ketone or aldehyde may increase. From these facts, the lower limit of the molar ratio of hydrogen chloride to ketones or aldehydes is preferably 0.01 or more, more preferably 0.05 or more, still more preferably 0.1 or more. The upper limit thereof is preferably 10 or less, more preferably 8 or less, and further preferably 5 or less.

Sulfuric acid is an acidic liquid represented by the chemical formula H ₂ SO ₄ . Generally, sulfuric acid is used as an aqueous solution of sulfuric acid diluted with water, and is called concentrated sulfuric acid or dilute sulfuric acid depending on its concentration. For example, dilute sulfuric acid is an aqueous sulfuric acid solution having a mass concentration of less than 90% by mass.
If the concentration of sulfuric acid used (concentration of sulfuric acid aqueous solution) is low, the amount of water increases, so that the reaction for producing bisphenol becomes difficult to proceed, the reaction time for producing bisphenol becomes long, and bisphenol can be produced efficiently. Can be difficult. Therefore, the concentration of sulfuric acid used is preferably 70% by mass or more, more preferably 75% by mass or more, and further preferably 80% by mass or more. The upper limit of the concentration of sulfuric acid used is usually 99.5% by mass or less or 99% by mass or less.

(Thiol)
In the production of bisphenol, thiol can be used as a cocatalyst in the reaction of condensing a ketone or aldehyde with an aromatic alcohol.
By using thiol as a cocatalyst, for example, in the production of 2,2-bis (4-hydroxy-3-methylphenyl) propane, the production of 24 bodies is suppressed, the selectivity of 44 bodies is increased, and the polycarbonate resin is produced. It is possible to obtain the effect of increasing the polymerization activity at the time and improving the color tone of the obtained polycarbonate resin. Although the details of the reason why the effect of improving the polymerization activity during the production of the polycarbonate resin and the effect of improving the color tone of the obtained polycarbonate resin are exhibited are not clear, the use of thiol is an inhibitor of the polymerization reaction for producing the polycarbonate resin. It is presumed that this is due to the fact that it is possible to suppress the production and the production of color-deteriorating substances.

Examples of the thiol used as a co-catalyst include mercaptocarboxylic acids such as mercaptoacetic acid, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid and 4-mercaptobutyric acid, methyl mercaptan, ethyl mercaptan, propyl mercaptan and butyl. Mercaptan, Pentyl mercaptan, Hexyl mercaptan, Heptyl mercaptan, Octyl mercaptan, Nonyl mercaptan, Decyl mercaptan (decane thiol), Undecyl mercaptan (undecanthiolu), Dodecyl mercaptan (dodecane thiol), Tridecyl mercaptan, Tetradecyl mercaptan Examples thereof include alkyl thiols such as decyl mercaptan and aryl thiols such as mercaptophenol.

If the molar ratio of the thiol cocatalyst to the ketone or aldehyde used for condensation ((the number of moles of the thiol cocatalyst / the number of moles of the ketone) or (the number of moles of the thiol cocatalyst / the number of moles of the aldehyde)) is small, the thiol cocatalyst is used. The effect of improving the reaction selectivity of bisphenol by using it cannot be obtained, and if it is too much, it may be mixed with bisphenol and the quality may deteriorate. From these facts, the lower limit of the molar ratio of the thiol cocatalyst to the ketone and the aldehyde is preferably 0.001 or more, more preferably 0.005 or more, still more preferably 0.01 or more. The upper limit thereof is preferably 1 or less, more preferably 0.5 or less, and further preferably 0.1 or less.

The thiol cocatalyst is preferably premixed with a ketone or aldehyde before being subjected to the reaction. The method for mixing the thiol with the ketone or aldehyde may be a mixture of the thiol with the ketone or the aldehyde, or a ketone or the aldehyde with the thiol. Further, as a method of mixing the mixed solution of thiol and ketone or aldehyde and the acid catalyst, the acid catalyst may be mixed with the mixed solution of thiol and ketone or aldehyde, and the acid catalyst is mixed with thiol and ketone or aldehyde. A mixed solution may be mixed, but it is preferable to mix a mixed solution of thiol and a ketone or aldehyde with an acid catalyst. Further, it is more preferable to supply the acid catalyst and the aromatic alcohol to the reaction vessel, and then supply the mixed solution of the thiol to the ketone or aldehyde to the reaction vessel for mixing.

(Organic solvent)
In the production of bisphenol, an organic solvent is usually used to dissolve or disperse the produced bisphenol.
The organic solvent is not particularly limited as long as it does not inhibit the production reaction of bisphenol, and examples thereof include aromatic hydrocarbons, aliphatic alcohols, and aliphatic hydrocarbons (here, aromatic alcohols as substrates and production. Bisphenol, which is a substance, is excluded from organic solvents.) These solvents may be used alone or in combination of two or more.

Examples of the aromatic hydrocarbon include benzene, toluene, xylene, ethylbenzene, diethylbenzene, isopropylbenzene, mesitylene and the like, and these solvents may be used alone or in combination of two or more. After using the aromatic hydrocarbon for the production of bisphenol, it can be recovered and purified by distillation or the like and reused. When reusing aromatic hydrocarbons, those having a low boiling point are preferable. One of the preferred aromatic hydrocarbons is toluene.

The aliphatic alcohol is an alkyl alcohol in which an alkyl group and a hydroxyl group are bonded. The fatty alcohol may be a monohydric aliphatic alcohol in which an alkyl group and one hydroxyl group are bonded, or may be a polyhydric aliphatic alcohol in which an alkyl group and two or more hydroxyl groups are bonded. Further, the alkyl group may be linear or branched, may be unsubstituted, or a part of the carbon atom of the alkyl group may be substituted with an oxygen atom.

As the number of carbon atoms increases, the lipophilicity of the aliphatic alcohol increases, it becomes difficult to mix with sulfuric acid, and it becomes difficult to generate monoalkyl sulfate, which will be described later. Therefore, the aliphatic alcohol preferably has 12 or less carbon atoms, and preferably 8 or less carbon atoms. More preferred.

Further, the aliphatic alcohol is preferably an alcohol in which an alkyl group and one hydroxyl group are bonded, and more preferably an alcohol in which an alkyl group having 1 to 8 carbon atoms and one hydroxyl group are bonded. More preferably, it is an alcohol in which an alkyl group having 1 to 5 carbon atoms and one hydroxyl group are bonded.

Specific aliphatic alcohols include, for example, methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, t-butanol, n-pentanol, i-pentanol, n-hexanol, n. -Heptanol, n-octanol, n-nonanol, n-decanol, n-undecanol, n-dodecanol, ethylene glycol, diethylene glycol, triethylene glycol and the like can be mentioned. One of the preferred aliphatic alcohols is methanol.

Aliphatic hydrocarbons include linear hydrocarbons having 5 to 18 carbon atoms such as n-pentane, n-hexane, n-heptane, and n-octane, and branched chain hydrocarbons having 5 to 18 carbon atoms such as isooctane. , Cyclohexane, cyclooctane, methylcyclohexane and other cyclic hydrocarbons having 5 to 18 carbon atoms.

If the mass ratio of the organic solvent to the ketone or aldehyde used for condensation ((mass of ketone / mass of organic solvent) or (mass of aldehyde / mass of organic solvent)) is too large, the ketone or aldehyde and the aromatic alcohol Is difficult to react and it takes a long time to react. If it is too small, the amount of ketones or aldehydes will be increased, and the bisphenol produced may solidify. From these facts, the mass ratio of the organic solvent to the ketone or aldehyde at the time of preparation is preferably 0.5 or more, and more preferably 1 or more. The upper limit thereof is preferably 100 or less, more preferably 50 or less.

It is more difficult for bisphenol to decompose when the generated bisphenol is dispersed without being completely dissolved in an organic solvent. In addition, it is preferable to use a solvent having a low solubility of bisphenol because it is possible to reduce the loss when recovering bisphenol from the reaction solution after the reaction is completed (for example, the loss to the filtrate during crystallization). Examples of the solvent having low solubility of bisphenol include aromatic hydrocarbons. Therefore, the organic solvent preferably contains aromatic hydrocarbons as a main component, preferably contains 55% by mass or more of aromatic hydrocarbons in the organic solvent, more preferably 70% by mass or more, and more preferably 80% by mass. It is more preferable to contain% or more.

When the acid catalyst contains sulfuric acid, the organic solvent contains an aliphatic alcohol, so that the sulfuric acid reacts with the aliphatic alcohol to produce monoalkyl sulfate, and this monoalkyl sulfate can also obtain a catalytic action. The effect is obtained. Therefore, when the acid catalyst contains sulfuric acid, the organic solvent is preferably an organic solvent containing an aliphatic alcohol. Further, the aliphatic alcohol is preferably an alkyl alcohol having 8 or less carbon atoms because the lipophilicity increases as the number of carbon atoms increases, it becomes difficult to mix with sulfuric acid, and it becomes difficult to generate monoalkyl sulfate.
In this way, by reacting sulfuric acid with an aliphatic alcohol to generate monoalkyl sulfate, the acid strength of the acid catalyst can be controlled, and condensation (enhancement) and coloring of the raw material ketone or aldehyde can be suppressed. .. Therefore, it is possible to easily and efficiently produce bisphenol in which the formation of by-products is suppressed and the coloring is reduced.

When sulfuric acid is reacted with an aliphatic alcohol to produce a monoalkyl sulfate and its catalytic action is also used, if the molar ratio of the aliphatic alcohol to sulfuric acid (the number of moles of the aliphatic alcohol / the number of moles of the sulfuric acid) is small, the raw material Condensation (enhancement) and coloring of ketones or aldehydes are remarkable. On the other hand, if the amount is large, the sulfuric acid concentration decreases and the reaction becomes slow. From these facts, the lower limit of the molar ratio of the aliphatic alcohol to sulfuric acid is preferably 0.01 or more, more preferably 0.05 or more, and further preferably 0.1 or more. The upper limit thereof is preferably 10 or less, more preferably 5 or less, and further preferably 3 or less.

From the above, the organic solvent can contain, for example, aromatic hydrocarbons and fatty alcohols, and the organic solvent contains 1 to 95% by mass of aromatic hydrocarbons and 0.1 to 10 fatty alcohols. It may contain% by mass.

(Preparation of reaction solution)
The method for preparing the reaction solution is not particularly limited, and a method of supplying an acid catalyst to a mixed solution of a mixture of an aromatic alcohol, an organic solvent, a ketone or an aldehyde, or a method of mixing an acid catalyst, an aromatic alcohol and an organic solvent. Examples thereof include a method of supplying a ketone or an aldehyde to the mixed solution.

In order to suppress an increase in the amount of ketone or aldehyde due to self-condensation, it is preferable to mix a solution containing an aromatic alcohol, an acid catalyst and an organic solvent with a solution containing a ketone or aldehyde. In this case, the solution containing the ketone or aldehyde may contain the ketone or aldehyde alone, or may contain a thiol or an organic solvent. The solution containing a ketone or aldehyde preferably contains a thiol.

(Reaction condition)
The formation reaction of bisphenol is a condensation reaction. If the reaction temperature of the formation reaction is too high, oxidative decomposition of thiol proceeds, and if it is too low, the time required for the reaction becomes long. Therefore, it is preferably 0 ° C. or higher and 50 ° C. It is as follows.

The reaction time of the production reaction is preferably 30 hours or less, more preferably 25 hours or less, still more preferably 20 hours or less because the produced bisphenol is decomposed if it is too long. The lower limit of the reaction time is usually 0.5 hours or more. It is possible to stop the reaction by adding water equal to or more than the amount of sulfuric acid used or an aqueous sodium hydroxide solution so that the sulfuric acid concentration is 45% by mass or less to reduce the sulfuric acid concentration.

(purification)
Purification of the bisphenol product obtained by the bisphenol production reaction can be carried out by a conventional method. For example, it can be purified by a simple means such as crystallization or column chromatography. Specifically, after the condensation reaction, the organic phase obtained by separating the reaction solution is washed with water or saline, and if necessary, neutralized and washed with sodium bicarbonate water or the like. The washed organic phase is then cooled and crystallized. When a large amount of aromatic alcohol is used, excess aromatic alcohol by distillation is distilled off before crystallization and then crystallization is performed.

In the present invention, in order to obtain the bisphenol product containing bisphenol C as the bisphenol composition of the present invention by leaving the bisphenol C produced as a by-product in the bisphenol production reaction system, the above method for purifying the bisphenol product is used. For example, it is preferable to adjust the purification conditions so that a predetermined amount of bisphenol C remains in the purified bisphenol product by appropriately combining crystallization, suspension washing, sprinkling washing and the like.

(Example of purification process)
As an example of a purification step suitable for the present invention, a method of purifying the bisphenol product obtained by the condensation reaction after washing in the washing step and then precipitating in the crystallization step will be described below.
That is, after the condensation reaction, the organic phase containing bisphenol obtained from the reaction solution is washed with desalted water, and the washed organic phase is cooled and crystallized. Wash multiple times as follows. Crystallization may also be performed a plurality of times.

<Washing process>
In the washing step, the organic phase (O1) containing bisphenol obtained from the reaction step and desalted water are mixed, and then the organic phase (O2) containing bisphenol and the aqueous phase (W1) are phase-separated to form an aqueous phase. After removing (W1) and mixing the first water washing step to obtain the organic phase (O2) containing bisphenol, the organic phase (O2) containing bisphenol obtained in the first water washing step, and desalted water, bisphenol The organic phase (O3) containing bisphenol and the aqueous phase (W2) are separated from each other, the aqueous phase (W2) is removed, and at least a second washing step of obtaining an organic phase (O3) containing bisphenol is performed. It is preferable to carry out the first water washing step so that the pH of the phase (W1) is 8.5 or more, and to carry out the second water washing step so that the electrical conductivity of the aqueous phase (W2) is 10 μS / cm.
Here, the demineralized water is water that has undergone ion exchange treatment, pure water, or the like and has an electric conductivity of 1.5 μS / cm or less.
The measurement temperature of the aqueous phase (W1) is preferably room temperature (20 to 30 ° C.), for example 25 ° C.

When the pH of the aqueous phase is lower than 7, the washing can be performed with a basic substance such as sodium hydroxide or sodium hydrogen carbonate, and the water washing can be performed again. The organic phase obtained after washing with a basic substance is washed again with water so that the pH of the aqueous phase becomes 8.5 or higher. Here, since the cleaning effect is low when the basicity of the aqueous phase (W1) is weak (low pH), the pH is preferably 8.5 or higher, more preferably 9 or higher. On the other hand, if the aqueous phase (W1) is strongly basic (high pH), bisphenol becomes a bisphenol salt and the amount of loss in washing with water increases. Therefore, the upper limit of the pH of the aqueous phase (W1) is usually 14 or less. It is preferably 13 or less, and more preferably 12 or less.

The measurement temperature of the electric conductivity of the aqueous phase (W2) in the second washing step is preferably room temperature (20 to 30 ° C.), for example 25 ° C.
The water phase (W2) in the second water washing step is washed so that the electric conductivity is preferably 10 μS / cm or less, but the electric conductivity of the water phase (W2) in the second water washing step is more preferably 9 μS / cm. It is cm or less, more preferably 8 μS / cm or less.

In the washing step, the organic phase containing bisphenol was washed with water to make the pH of the obtained aqueous phase basic at pH 8.5 or higher, and then repeated washing with water as necessary to obtain the electrical conductivity of the obtained aqueous phase. When the value is 10 μS / cm or less, it is preferable to perform the crystallization step.

Generated by washing with demineralized water so that the pH of the aqueous phase (W1) in the first water washing step becomes equal to or higher than the above lower limit and the electrical conductivity of the aqueous phase (W2) in the second washing step becomes equal to or lower than the above upper limit. Polycarbonate resin that has good hue by highly removing impurities such as by-products, residual catalyst, and residual thiol in bisphenol, and has high polymerization reaction efficiency and excellent hue when used as a raw material bisphenol for polycarbonate resin. It is possible to obtain a bisphenol composition capable of producing the above. In particular, in the condensation reaction using thiol as a cocatalyst, acidic thionium is produced from the thiol, which is contained in the bisphenol composition and inhibits the polymerization reaction during the production of the polycarbonate resin. As described above, the aqueous phase (W1) ) And the electrical conductivity of the aqueous phase (W2) are controlled, so that thionium can be efficiently removed and polymerization inhibition by thionium can be prevented.

The temperature in the washing step is preferably 90 to 50 ° C., particularly 85 to 55 ° C. so that bisphenol can be efficiently precipitated by cooling in the crystallization step described later without evaporating the solvent. .. The cleaning time (time for adding desalinated water to the organic phase and mixing) is usually about 1 to 120 minutes.

<Crystalization process>
The cooling temperature in the crystallization step is 10 to 120 ° C. lower than the temperature of the organic phase (O3) obtained from the washing step, and is preferably 40 to -20 ° C., particularly about 30 to -10 ° C. By cooling the organic phase (O3) after washing to such a temperature, the bisphenol composition can be efficiently precipitated.

The bisphenol composition precipitated in the crystallization step can be recovered by solid-liquid separation by filtration, centrifugation, decantation or the like.

Even when the above-mentioned washing step and crystallization step are performed, it is preferable to control the purification conditions so that the bisphenol C remains in a predetermined ratio in the bisphenol composition obtained after purification.

<Use of bisphenol>
The bisphenol composition of the present invention is a polyether resin, polyester resin, polyarylate resin, polycarbonate resin, polyurethane used for various purposes such as optical materials, recording materials, insulating materials, transparent materials, electronic materials, adhesive materials, and heat resistant materials. Components, curing agents, additives or their components such as various thermoplastic resins such as resins and acrylic resins, and various thermosetting resins such as epoxy resins, unsaturated polyester resins, phenol resins, polybenzoxazine resins and cyanate resins. It can be used as a precursor or the like. It is also useful as an additive for a color developer such as a heat-sensitive recording material, a fading inhibitor, a bactericidal agent, and an antibacterial and antifungal agent.
Of these, it is preferable to use it as a raw material (monomer) for a thermoplastic resin or a thermosetting resin, and it is more preferable to use it as a raw material for a polycarbonate resin or an epoxy resin because it can impart good mechanical properties. It is also preferable to use it as a color developer, and it is more preferable to use it in combination with a leuco dye and a color change temperature adjusting agent.

[Manufacturing method of polycarbonate resin]
As a method for producing a polycarbonate resin using the bisphenol composition of the present invention, the bisphenol composition of the present invention and diphenyl carbonate or the like are transesterified in the presence of an alkali metal compound and / or an alkaline earth metal compound. There is a way to make it.
The bisphenol composition of the present invention may contain only one type of bisphenol, or may contain two or more types. A copolymerized polycarbonate resin can be produced by using two or more kinds of bisphenols. Further, a dihydroxy compound other than the bisphenol composition of the present invention can be used in combination for reaction.
The transesterification reaction can be carried out by appropriately selecting a known method, and an example of a method for producing a polycarbonate resin using the bisphenol composition of the present invention and diphenyl carbonate as raw materials will be described below.

In the above method for producing a polycarbonate resin, it is preferable to use diphenyl carbonate in an excess amount with respect to the bisphenol in the bisphenol composition of the present invention. The amount of diphenyl carbonate used for bisphenol is preferably large in that the produced polycarbonate resin has few terminal hydroxyl groups and is excellent in thermal stability of the polymer, and the transesterification reaction rate is high, and the polycarbonate having a desired molecular weight. It is preferable that the amount is small in that the resin can be easily produced. From these facts, the amount of diphenyl carbonate used per 1 mol of bisphenol is usually 1.001 mol or more, preferably 1.002 mol or more. In addition, it is usually 1.3 mol or less, preferably 1.2 mol or less.

As a method for supplying the raw materials, the bisphenol composition and diphenyl carbonate of the present invention can be supplied as a solid, but it is preferable that one or both of them are melted and supplied in a liquid state.

A transesterification catalyst is usually used when producing a polycarbonate resin by a transesterification reaction between diphenyl carbonate and bisphenol. In the above method for producing a polycarbonate resin, it is preferable to use an alkali metal compound and / or an alkaline earth metal compound as the transesterification catalyst. These may be used alone or in combination of two or more in any combination and ratio. Practically, it is desirable to use an alkali metal compound.

The amount of the catalyst used is usually 0.05 μmol or more, preferably 0.08 μmol or more, and more preferably 0.10 μmol or more with respect to 1 mol of bisphenol or diphenyl carbonate. The upper limit thereof is usually 100 μmol or less, preferably 50 μmol or less, and more preferably 20 μmol or less.
When the amount of the catalyst used is within the above range, the polymerization activity required for producing a polycarbonate resin having a desired molecular weight can be easily obtained, the polymer hue is excellent, and excessive polymer branching does not proceed. It is easy to obtain a polycarbonate resin with excellent fluidity during molding.

In order to produce the polycarbonate resin by the above method, it is preferable that both of the above raw materials are continuously supplied to the raw material mixing tank, and the obtained mixture and the transesterification catalyst are continuously supplied to the polymerization tank.
In the production of the polycarbonate resin by the transesterification method, both raw materials supplied to the raw material mixing tank are usually stirred uniformly and then supplied to a polymerization tank to which a transesterification catalyst is added to produce a polymer.

In the production of the polycarbonate resin using the bisphenol composition of the present invention, the polymerization reaction temperature is preferably 80 to 400 ° C, particularly 150 to 350 ° C. The polymerization time is appropriately adjusted according to the ratio of raw materials, the desired molecular weight of the polycarbonate resin, etc. However, if the polymerization time is long, quality deterioration such as deterioration of color tone becomes apparent, so it may be 10 hours or less. It is preferably 8 hours or less, and more preferably 8 hours or less. The lower limit of the polymerization time is usually 0.1 hours or more, or 0.3 hours or more.

According to the bisphenol composition of the present invention, a polycarbonate resin having a good hue and excellent transparency can be produced. For example, a polycarbonate resin having a viscosity average molecular weight (Mv) of 1000 to 100,000, preferably 1500 to 35,000, having a pellet YI of 10 or less and having a good hue and excellent transparency can be produced in a short time.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples as long as the gist of the present invention is not exceeded.

[Raw materials and reagents]
In the following examples and comparative examples, orthocresol, toluene, sodium hydroxide, sulfuric acid, dodecanethiol, acetone, sodium hydrogencarbonate, cesium carbonate, acetonitrile, acetic acid, ammonium acetate, methylene chloride are used in Fuji Film Wako Pure Chemical Industries, Ltd. The reagent used was.
As diphenyl carbonate, a product manufactured by Mitsubishi Chemical Corporation was used.

[analysis]
<Composition of bisphenol C production reaction solution, analysis of bisphenol C in bisphenol C composition>
The composition analysis of the bisphenol C production reaction solution and the bisphenol C analysis in the bisphenol C composition were carried out by high performance liquid chromatography under the following procedure and conditions.
・ Equipment: "LC-2010A" manufactured by Shimadzu Corporation
Imtakt ScherzoSM-C18 3μm 250mm x 3.0mm ID
・ Low pressure gradient method ・ Analysis temperature: 40 ℃
・ Eluent composition:
Solution Ammonium acetate: Acetic acid: Demineralized water = 3.000 g: 1 mL: 1 L solution Solution B Ammonium acetate: Acetic acid: Acetonitrile: Demineralized water = 1.500 g: 1 mL: 900 mL: 150 mL solution ・ Elution at 0 minutes of analysis time The liquid composition is liquid A: liquid B = 60:40 (volume ratio, the same applies hereinafter).
The analysis time of 0 to 41.67 minutes was gradually changed to solution A: solution B = 10:90.
Analysis time 41.67 to 50 minutes is maintained at solution A: solution B = 10:90,
The analysis was performed at a flow rate of 0.34 mL / min.

<Distribution of bisphenol C>
The bisphenol C in the bisphenol C composition was sorted by high performance liquid chromatography for sorting under the following procedure and conditions.
(Primary distribution)
・ Equipment: "LC10A" manufactured by Shimadzu Corporation
Imtaket UNISON UK C18 3 μm 250 mm x 4.6 mm ID
・ Low pressure gradient method ・ Analysis temperature: 40 ℃
・ Eluent composition:
Solution A 0.1% formic acid Solution B Methanol ・ When the analysis time is 0 to 15 minutes, the eluent composition is changed to solution A: solution B = 60:40 (volume ratio, the same applies hereinafter).
For the analysis time of 15 to 30 minutes, gradually change to solution A: solution B = 10:90.
Analysis time 30-45 minutes is maintained at solution A: solution B = 0: 100,
The analysis was performed at a flow rate of 1.0 mL / min.
・ Number of collections: 62 times

(Secondary distribution)
The solution obtained by the primary fractionation was dried by an evaporator and dissolved in 1 mL of acetonitrile to prepare a sample for the secondary fractionation.
-Device: Agilent "LC1100"
Imtaket UNISON UK C18 3 μm 250 mm x 4.6 mm ID
・ Low pressure gradient method ・ Analysis temperature: 40 ℃
・ Eluent composition:
Solution A 0.1% formic acid Solution B Methanol ・ When the analysis time is 0 minutes, the eluent composition is changed to solution A: solution B = 30:70 (volume ratio, the same applies hereinafter).
The analysis time of 0 to 15 minutes was gradually changed to solution A: solution B = 0: 100.
Analysis time 15 to 20 minutes is maintained at solution A: solution B = 0: 100,
The analysis was performed at a flow rate of 1.0 mL / min.
・ Number of collections: 32 times

< ^{1 1} H NMR>
Proton nuclear magnetic resonance ( ¹ H NMR) measurement was carried out by drying the solution obtained by preparative bisbisphenol C with an evaporator and using "JNM-ECS400 type" manufactured by JEOL Ltd. as a deuterated chloroform solution. did.

<Measurement of molecular weight of bisphenol C>
The molecular weight of bisphenol C was measured using high performance liquid chromatography mass spectrometry (LCMS). High Performance Liquid Chromatography Mass Spectrometry (LCMS) was performed under the following procedure and conditions.
-Separator: "Agilent 1200" manufactured by Agilent Technologies, Inc.
Imtaket ScherzoSM-C18 3μm 150mm x 4.6mm ID
・ Low pressure gradient method ・ Analysis temperature: 40 ℃
・ Eluent composition:
Solution A Ammonium acetate: Acetic acid: Demineralized water = 3.000 g: 1 mL: 1 L solution Solution B Ammonium acetate: Acetic acid: Acetonitrile = 1.500 g: 1 mL: 1 L solution ・ When the analysis time is 0 minutes, the eluent composition is Solution A: Solution B = 60:40 (volume ratio, the same applies hereinafter)
The analysis time of 0 to 25 minutes was gradually changed to solution A: solution B = 90:10.
Analysis time 25 to 30 minutes is maintained at solution A: solution B = 90:10,
The analysis was performed at a flow rate of 1.0 mL / min.
-Detection wavelength: 280 nm
-Mass spectrometer: "Agilent LC / MS 6130" manufactured by Agilent Technologies, Inc.
-Ion source: ESI (Postive / Negative) AJS probe used

<Analysis of bisphenol C in bisphenol C composition>
The analysis of bisphenol C in the bisphenol C composition was carried out in the same manner as in <Composition of bisphenol C production reaction solution, analysis of bisphenol C in bisphenol C composition>. The purity of bisphenol C in bisphenol in the bisphenol C composition produced in the present invention is usually 99% by mass or more, and the amount of bisphenol other than bisphenol C produced is very small. Therefore, bisphenol C in the bisphenol C composition The content can be regarded as the bisphenol content.

<Identification of isopropenyl cresol>
Identification of isopropenyl cresol was performed using a gas chromatograph by the following procedure and conditions.
-Device: "Agilent 6890" manufactured by Agilent Technologies
-Column: "DB-1MS" manufactured by Agilent Technologies (inner diameter 0.25 mm x 30 m x 0.25 μm)
・ Carrier gas: Helium
Flow rate: 1 cm per minute ³
-Inlet temperature: 280 ° C
・ Transfer temperature: 250 ℃
・ Ion source temperature: 250 ℃
-Column temperature rise pattern: First, hold at 50 ° C. for 3 minutes, then raise the temperature to 320 ° C. at 10 ° C. per minute, and hold at 280 ° C. for 5 minutes.

<Measurement of pH>
For pH measurement, use the pH meter "pH METER" manufactured by HORIBA, Ltd.
ES-73 ”was used for the aqueous phase at 25 ° C. taken out of the flask.

<Electrical conductivity>
The electric conductivity was measured using an electric conductivity meter "COND METER D-71" manufactured by HORIBA, Ltd. for an aqueous phase at 25 ° C. taken out from the flask.

<Methanol-dissolved color of bisphenol C composition>
The methanol-dissolved color of the bisphenol C composition is determined by putting 10 g of the bisphenol C composition and 10 g of methanol in a test tube "P-24" (24 mmφ x 200 mm) manufactured by Nichiden Rika Glass Co., Ltd. to make a uniform solution, and then at room temperature (about 20). The number of Hazen colors was measured using "SE6000" manufactured by Nippon Denshoku Kogyo Co., Ltd. at (° C.).

<Melted color difference of bisphenol C composition>
To determine the melt color difference of the bisphenol C composition, put 20 g of the bisphenol C composition in a test tube "P-24" (24 mmφ x 200 mm) manufactured by Nichiden Rika Glass Co., Ltd., melt it at 190 ° C. for 30 minutes, and manufacture it by Nippon Denshoku Kogyo Co., Ltd. The number of Hazen colors was measured using "SE6000".

<Thermal color stability of bisphenol C composition>
For the thermal color stability of the bisphenol C composition, 20 g of the bisphenol C composition was placed in a test tube "P-24" (24 mmφ x 200 mm) manufactured by Nichiden Rika Glass Co., Ltd. and melted at 190 ° C. for 4 hours. The number of Hazen colors was measured using "SE6000" manufactured by Japan.

<Pyrolysis stability of bisphenol C composition>
For the thermal decomposition stability of the bisphenol C composition, 20 g of the bisphenol C composition was placed in a test tube "P-24" (24 mmφ x 200 mm) manufactured by Nichiden Rika Glass Co., Ltd. and melted at 190 ° C. for 2 hours to produce the bisphenol C formation reaction. The same as the composition analysis of the liquid was carried out, and the amount of isopropenyl cresol produced was measured.

<Viscosity average molecular weight>
The viscosity average molecular weight (Mv) of the polycarbonate resin is determined by dissolving the polycarbonate resin in methylene chloride (concentration 6.0 g / L), measuring the specific viscosity (ηsp) at 20 ° C. using a Uberode viscosity tube, and using the following formula. The viscosity average molecular weight (Mv) was calculated.
ηsp / C = [η] (1 + 0.28ηsp)
[η] = 1.23 × 10 ^-4 Mv ^0.83

<Pellet YI>
The pellet YI (transparency of the polycarbonate resin) was evaluated by measuring the YI value (yellowness index value) in the reflected light of the polycarbonate resin pellet in accordance with ASTM D1925. A spectrocolorimeter "CM-5" manufactured by Konica Minolta Co., Ltd. was used as an apparatus, and a measurement diameter of 30 mm and SCE were selected as measurement conditions.
The calibration glass "CM-A212" for petri dish measurement was fitted into the measuring section, and the zero calibration box "CM-A124" was placed over it to perform zero calibration, and then white calibration was performed using the built-in white calibration plate. .. Next, measurement was performed using the white calibration plate "CM-A210", where L * was 99.40 ± 0.05, a * was 0.03 ± 0.01, and b * was -0.43 ± 0.01. , YI was confirmed to be −0.58 ± 0.01.
YI was measured by packing pellets to a depth of about 40 mm in a cylindrical glass container having an inner diameter of 30 mm and a height of 50 mm. The operation of taking out the pellets from the glass container and then performing the measurement again was repeated twice, and the average value of the measured values of a total of three times was used.

[Reference example 1]
85 g of bisphenol C composition and 4.5 g of sodium hydroxide were placed in a 500 mL eggplant-shaped flask equipped with a stirrer, a thermometer and a distillation apparatus, and immersed in an oil bath heated to 195 ° C. After confirming that the bisphenol C in the eggplant-shaped flask was melted, the inside of the flask was gradually depressurized using a vacuum pump to obtain a full vacuum. After a while, evaporation started, and vacuum distillation was carried out until the distillation subsided. The resulting fraction was found by gas chromatography equipped with a massimeter detector to be a mixture of cresol and isopropenyl cresol produced by thermal decomposition of bisphenol C. Using the obtained fraction, the retention time of isopropenyl cresol under the composition analysis conditions of the bisphenol C production reaction solution was confirmed.

[Example 1]
(1) Preparation of the first mixed solution In a separable flask equipped with a thermometer, a dropping funnel, a jacket and an anchor type stirring blade, 320 g of toluene, 15 g of methanol and 230 g (2.13 mol) of orthocresol were placed in a nitrogen atmosphere. The temperature was set to 10 ° C. or lower. Then, 95 g of 98 wt% sulfuric acid was slowly added over 0.3 hours with stirring, and then cooled to 5 ° C. or lower.

(2) Preparation of Second Mixed Solution 50 g of toluene, 65 g (1.12 mol) of acetone and 5.4 g of dodecanethiol were mixed in a 500 mL Erlenmeyer flask to prepare a second mixed solution (dropping solution).

(3) Preparation of reaction solution After the internal temperature of the first mixed solution is lowered to 5 ° C. or lower, the second mixed solution is subjected to the second mixed solution using the dropping funnel over 1 hour so that the internal temperature does not reach 10 ° C. or higher. And supplied to prepare a reaction solution.

(4) Reaction The prepared reaction solution was stirred at an internal temperature of 10 ° C. for 2.5 hours.

(5) Purification (cleaning)
After completion of the reaction, 190 g of a 25% aqueous sodium hydroxide solution was supplied and the temperature was raised to 80 ° C. After reaching 80 ° C., the mixture was allowed to stand and the aqueous phase of the lower phase was extracted. 400 g of desalted water was added to the obtained first organic phase, mixed for 30 minutes and allowed to stand to remove the aqueous phase. 120 g of a 1.5 mass% sodium hydrogen carbonate solution was added to the obtained second organic phase, mixed for 30 minutes and allowed to stand, and the lower phase was extracted. Further, 120 g of a 1.5 mass% sodium hydrogen carbonate solution was added to the obtained third organic phase, mixed for 30 minutes and allowed to stand, and the lower phase was extracted. The obtained fourth organic phase was extracted and its mass was measured and found to be 666 g.

When a part of the fourth organic phase was taken out and the composition of the fourth organic phase was confirmed by high-speed liquid chromatography, the content of orthocresol was 5.3% by mass (5.3% by mass × mass of organic phase 666 g ÷ ortho). Molecular weight of cresol 108 g / mol ÷ Amount of substance of orthocresol charged 2.1 mol = 15.3 mol%), bisphenol C 31.5 mass% (31.5 mass% × mass of organic phase 666 g × 2 ÷ bisphenol The molecular weight of C was 256 g / mol ÷ the amount of substance of the charged orthocresol was 2.1 mol = 78.0 mol%).

(6) Purification (washing with water and crystallization)
200 g of desalted water was added to the obtained fourth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (first aqueous phase) was removed to obtain a fifth organic phase. The pH of the first aqueous phase was 9.7. 200 g of desalted water was added to the obtained fifth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (second aqueous phase) was removed to obtain a sixth organic phase. 200 g of desalted water was added to the obtained sixth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (third aqueous phase) was removed. The electrical conductivity of the third aqueous phase was 2.7 μS / cm.

The obtained sixth organic phase was cooled from 80 ° C. to 20 ° C. and maintained at 20 ° C. to precipitate bisphenol C. Then, after cooling to 10 ° C. and reaching 10 ° C., solid-liquid separation was performed using a centrifuge to obtain a crudely purified wet cake. The obtained wet cake was washed by sprinkling 500 g of toluene, and solid-liquid separation was performed using a centrifuge to obtain a purified wet cake. The obtained refined wet cake was distilled off with a light boiling point at an oil bath temperature of 100 ° C. under reduced pressure using an evaporator equipped with an oil bath to obtain 190 g of a white bisphenol C composition.

When the methanol-dissolved color of the obtained bisphenol C composition was measured, the number of Hazen colors was 0. When the melt color difference of the obtained bisphenol C composition was measured, the number of Hazen colors was 3. Moreover, when the thermal color tone stability of the obtained bisphenol C composition was measured, the number of Hazen colors was 26. Further, when the thermal decomposition stability of the obtained bisphenol C composition was measured, the amount of isopropenyl cresol produced was 166 mass ppm.

When the quality of the obtained bisphenol C composition was confirmed, a characteristic peak was detected at a retention time of 34.14 minutes on a high performance liquid chromatograph. In order to identify the components of this peak, it was measured by high performance liquid chromatography equipped with a mass meter, and it was found that the molecular weight was 510 g / mol.
1.6 g of the obtained bisphenol C composition was dissolved in an acetonitrile solution, and the above-mentioned characteristic peaks were subjected to primary and secondary preparative collection using liquid chromatography for preparative use. The solution obtained by preparative separation was dried to dryness, the obtained dry matter was dissolved in deuterated chloroform, and NMR was measured. As a result, 2,2'-bi [2'-bi [] having a structure represented by the following structural formula (I). It was confirmed that it was 1-hydroxy-4- (4-hydroxy-3-methylphenyl) dimethylmethyl] -6-methylphenyl].
Bisbisphenol C; ¹ NMR (400MHz, CDCl3) 1.59 (Me, s, 12H), (Me, s, 6H), 2.19 (Me, s, 6H), 2.24 (OH, s, 2H) ), 4.59 (OH, s, 2H), 5.09 (OH, s, 2H), 6.60 (H, d, 2H, 3 j = 8.4Hz), 6.75 (H, d, ^2H, 4 j = 2.0Hz). 6.86 (H, dd, 2H), 6.91 (H, dd, 4H).

The obtained bisphenol C composition contained 3% by mass ppm of bisphenol C.
The bisphenol C content in the obtained bisphenol C composition was 99.8% by mass.

[Example 2]
(1) Preparation of the first mixed solution In a separable flask equipped with a thermometer, a dropping funnel, a jacket and an anchor type stirring blade, 320 g of toluene, 15 g of methanol and 230 g (2.13 mol) of orthocresol were placed in an air atmosphere. The temperature was set to 10 ° C. or lower. Then, 95 g of 98 wt% sulfuric acid was slowly added over 0.3 hours with stirring, and then cooled to 5 ° C. or lower.

(2) Preparation of Second Mixed Solution 50 g of toluene, 65 g (1.12 mol) of acetone and 5.4 g of dodecanethiol were mixed in a 500 mL Erlenmeyer flask to prepare a second mixed solution (dropping solution).

(3) Preparation of reaction solution After the internal temperature of the first mixed solution is lowered to 5 ° C. or lower, the second mixed solution is subjected to the second mixed solution using the dropping funnel over 1 hour so that the internal temperature does not reach 10 ° C. or higher. And supplied to prepare a reaction solution.

(4) Reaction The prepared reaction solution was stirred at an internal temperature of 10 ° C. for 5 hours.

(5) Purification (cleaning)
After completion of the reaction, 190 g of a 25% aqueous sodium hydroxide solution was supplied and the temperature was raised to 80 ° C. After reaching 80 ° C., the mixture was allowed to stand and the aqueous phase of the lower phase was extracted. 400 g of desalted water was added to the obtained first organic phase, mixed for 30 minutes and allowed to stand to remove the aqueous phase. 120 g of a 1.5 mass% sodium hydrogen carbonate solution was added to the obtained second organic phase, mixed for 30 minutes and allowed to stand, and the lower phase was extracted. Further, 120 g of a 1.5 mass% sodium hydrogen carbonate solution was added to the obtained third organic phase, mixed for 30 minutes and allowed to stand, and the lower phase was extracted. The obtained fourth organic phase was extracted and its mass was measured and found to be 666 g.

When a part of the fourth organic phase was taken out and the composition of the fourth organic phase was confirmed by high-speed liquid chromatography, the content of orthocresol was 5.3% by mass (5.3% by mass × mass of organic phase 666 g ÷ ortho). Molecular weight of cresol 108 g / mol ÷ Amount of substance of orthocresol charged 2.1 mol = 15.3 mol%), bisphenol C 31.5 mass% (31.5 mass% × mass of organic phase 666 g × 2 ÷ bisphenol The molecular weight of C was 256 g / mol ÷ the amount of substance of the charged orthocresol was 2.1 mol = 78.0 mol%).

(6) Purification (washing with water and crystallization)
200 g of desalted water was added to the obtained fourth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (first aqueous phase) was removed to obtain a fifth organic phase. The pH of the first aqueous phase was 9.7. 200 g of desalted water was added to the obtained fifth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (second aqueous phase) was removed to obtain a sixth organic phase. 200 g of desalted water was added to the obtained sixth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (third aqueous phase) was removed. The electrical conductivity of the third aqueous phase was 2.1 μS / cm.

The obtained sixth organic phase was cooled from 80 ° C. to 20 ° C. and maintained at 20 ° C. to precipitate bisphenol C. Then, after cooling to 10 ° C. and reaching 10 ° C., solid-liquid separation was performed using a centrifuge to obtain a crudely purified wet cake. The obtained wet cake was washed by sprinkling 500 g of toluene, and solid-liquid separation was performed using a centrifuge to obtain a purified wet cake. The obtained refined wet cake was distilled off with a light boiling point at an oil bath temperature of 100 ° C. under reduced pressure using an evaporator equipped with an oil bath to obtain 190 g of a white bisphenol C composition.

The bisphenol C content in the obtained bisphenol C composition was 99.7% by mass, and the bisphenol C content was 246% by mass.
Moreover, when the methanol-dissolved color of the obtained bisphenol C composition was measured, the number of Hazen colors was 0. When the melt color difference of the obtained bisphenol C composition was measured, the number of Hazen colors was 5. Moreover, when the thermal color tone stability of the obtained bisphenol C composition was measured, the number of Hazen colors was 27. Further, when the thermal decomposition stability of the obtained bisphenol C composition was measured, the amount of isopropenyl cresol produced was 154 mass ppm.

[Comparative Example 1]
(1) Preparation of the first mixed solution In a separable flask equipped with a thermometer, a dropping funnel, a jacket and an anchor type stirring blade, 320 g of toluene, 15 g of methanol and 230 g (2.13 mol) of orthocresol were placed in a nitrogen atmosphere. The temperature was set to 10 ° C. or lower. Then, 95 g of 98 wt% sulfuric acid was slowly added over 0.3 hours with stirring, and then cooled to 5 ° C. or lower.

(2) Preparation of Second Mixed Solution 50 g of toluene, 65 g (1.12 mol) of acetone and 5.4 g of dodecanethiol were mixed in a 500 mL Erlenmeyer flask to prepare a second mixed solution (dropping solution).

(3) Preparation of reaction solution After the internal temperature of the first mixed solution is lowered to 5 ° C. or lower, the second mixed solution is subjected to the second mixed solution using the dropping funnel over 1 hour so that the internal temperature does not reach 10 ° C. or higher. And supplied to prepare a reaction solution.

(4) Reaction The prepared reaction solution was stirred at an internal temperature of 10 ° C. for 2.5 hours.

(5) Purification (cleaning)
After completion of the reaction, 190 g of a 25% aqueous sodium hydroxide solution was supplied and the temperature was raised to 80 ° C. After reaching 80 ° C., the mixture was allowed to stand and the aqueous phase of the lower phase was extracted. 400 g of desalted water was added to the obtained first organic phase, mixed for 30 minutes and allowed to stand to remove the aqueous phase. 120 g of a 1.5 mass% sodium hydrogen carbonate solution was added to the obtained second organic phase, mixed for 30 minutes and allowed to stand, and the lower phase was extracted. Further, 120 g of a 1.5 mass% sodium hydrogen carbonate solution was added to the obtained third organic phase, mixed for 30 minutes and allowed to stand, and the lower phase was extracted. The obtained fourth organic phase was extracted and its mass was measured and found to be 666 g.

When a part of the fourth organic phase was taken out and the composition of the fourth organic phase was confirmed by high-speed liquid chromatography, the content of orthocresol was 5.3% by mass (5.3% by mass × mass of organic phase 666 g ÷ ortho). Molecular weight of cresol 108 g / mol ÷ Amount of substance of orthocresol charged 2.1 mol = 15.3 mol%), bisphenol C 31.5 mass% (31.5 mass% × mass of organic phase 666 g × 2 ÷ bisphenol The molecular weight of C was 256 g / mol ÷ the amount of substance of the charged orthocresol was 2.1 mol = 78.0 mol%).

(6) Purification (washing with water and crystallization)
The obtained fourth organic phase was cooled from 80 ° C. to 20 ° C. and maintained at 20 ° C. to precipitate bisphenol C. Then, after cooling to 10 ° C. and reaching 10 ° C., solid-liquid separation was performed using a centrifuge to obtain a crudely purified wet cake.

In a separable flask equipped with a thermometer, a dropping funnel, a jacket and an anchor-type stirring blade, put the whole amount of the crudely purified wet cake obtained in a nitrogen atmosphere and 420 g of toluene, and raise the temperature to 80 ° C. to obtain a uniform solution. It was. 200 g of desalted water was added to the obtained uniform solution, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (first aqueous phase) was removed to obtain a fifth organic phase. The pH of the first aqueous phase was 9.2. 200 g of desalted water was added to the obtained fifth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (second aqueous phase) was removed to obtain a sixth organic phase. 200 g of desalted water was added to the obtained sixth organic phase, mixed for 30 minutes and allowed to stand, and the lower aqueous phase (third aqueous phase) was removed to obtain a seventh organic phase. The electrical conductivity of the third aqueous phase was 2.3 μS / cm.

The obtained seventh organic phase was cooled from 80 ° C. to 20 ° C. and maintained at 20 ° C. to precipitate bisphenol C. Then, after cooling to 10 ° C. and reaching 10 ° C., solid-liquid separation was performed using a centrifuge to obtain a wet cake. The obtained wet cake was washed by sprinkling 200 g of toluene, and solid-liquid separation was performed using a centrifuge to obtain a purified wet cake. The obtained refined wet cake was distilled off with a light boiling point at an oil bath temperature of 100 ° C. under reduced pressure using an evaporator equipped with an oil bath to obtain 183 g of a white bisphenol C composition.

The content of bisphenol C in the obtained bisphenol C composition was 99.9% by mass, and bisphenol C was not detected (the lower limit of quantification was 0.1% by mass).
Moreover, when the methanol-dissolved color of the obtained bisphenol C composition was measured, the number of Hazen colors was 3. When the melt color difference of the obtained bisphenol C composition was measured, the number of Hazen colors was 48. Moreover, when the thermal color tone stability of the obtained bisphenol C composition was measured, the number of Hazen colors was 120. Further, when the thermal decomposition stability of the obtained bisphenol C was measured, the amount of isopropenyl cresol produced was 485 mass ppm.

[Comparative Example 2]
Bisbisphenol C in the reagent C of Fuji Film Wako Pure Chemical Industries, Ltd. was not detected (the lower limit of quantification was 0.1 mass ppm).
When the methanol-dissolved color of bisphenol C of the reagent was measured, the number of Hazen colors was 20. Moreover, when the melt color difference of bisphenol C of the reagent was measured, the number of Hazen colors was 46. Moreover, when the thermal color tone stability of bisphenol C of the reagent was measured, the number of Hazen colors was 114. Further, when the thermal decomposition stability of bisphenol C of the reagent was measured, the amount of isopropenyl cresol produced was 585 mass ppm.

For Examples 1 and 2 and Comparative Examples 1 and 2, the content of bisphenol C in the bisphenol C composition and the methanol dissolution color, melt color difference, thermal color tone stability, and thermal decomposition stability are summarized in Table 1. ..
From Table 1, it can be seen that by containing bisbisphenol C in an amount of 1 mass ppm or more and 300 mass ppm or less, methanol dissolved color, melt color difference, and thermal color tone stability are improved. Further, it can be seen that the thermal decomposition stability is also improved by containing bisbisphenol C in an amount of 1 mass ppm or more and 300 mass ppm or less.

[Example 3]
100.00 g (0.39 mol of bisphenol C) and 86.49 g (0.4) of diphenyl carbonate obtained in Example 1 in a glass reaction tank having an internal volume of 150 mL equipped with a stirrer and a distillate. (Mole) and 479 μL of a 400 mass ppm cesium carbonate aqueous solution were added. The operation of reducing the pressure of the glass reaction vessel to about 100 Pa and then restoring the pressure to atmospheric pressure with nitrogen was repeated three times to replace the inside of the reaction vessel with nitrogen. Then, the reaction vessel was immersed in an oil bath at 200 ° C. to dissolve the contents.

The rotation speed of the stirrer is set to 100 times per minute, and the pressure in the reaction vessel is adjusted to absolute pressure over 40 minutes while distilling off the phenol produced by the oligomerization reaction of bisphenol C and diphenyl carbonate in the reaction vessel. The pressure was reduced from 101.3 kPa to 13.3 kPa. Subsequently, the transesterification reaction was carried out for 80 minutes while maintaining the pressure in the reaction vessel at 13.3 kPa and further distilling off phenol. Then, the temperature outside the reaction vessel was raised to 250 ° C., and the pressure inside the reaction vessel was reduced from 13.3 kPa to 399 Pa in absolute pressure over 40 minutes to remove the distilled phenol from the system.

Then, the temperature outside the reaction vessel was raised to 280 ° C., the absolute pressure in the reaction vessel was reduced to 30 Pa, and the polycondensation reaction was carried out. The polycondensation reaction was terminated when the stirrer in the reaction tank became a predetermined stirring power. The time from the temperature rise to 280 ° C. to the end of the polymerization (post-stage polymerization time) was 210 minutes.

Next, the reaction vessel was repressurized to 101.3 kPa with nitrogen at an absolute pressure, and then the pressure was increased to 0.2 MPa with a gauge pressure, and the polycarbonate resin was extracted from the bottom of the reaction vessel in a strand shape to obtain a strand-shaped polycarbonate resin. ..
Then, the strands were pelletized using a rotary cutter to obtain a pellet-shaped polycarbonate resin.

The viscosity average molecular weight (Mv) of the obtained polycarbonate resin was 24,800, and the pellet YI was 6.9.

[Comparative Example 3]
In Example 3, instead of 100.00 g (bisphenol C 0.39 mol) of the bisphenol C composition obtained in Example 1, 100.00 g (bisphenol C 0.39) of the bisphenol C composition obtained in Comparative Example 1 was used. It was carried out in the same manner as in Example 3 except that it was used.
The time from the temperature rise to 280 ° C. to the end of the polymerization (post-stage polymerization time) was 230 minutes.
The viscosity average molecular weight (Mv) of the obtained polycarbonate resin was 24,800, and the pellet YI was 10.2.

For Example 3 and Comparative Example 3, the bisphenol C content in the bisphenol C composition used for producing the polycarbonate resin and the obtained pellet YI of the polycarbonate resin are summarized in Table 2.
From Table 2, it can be seen that the pellet YI of the obtained polycarbonate resin is improved by using the bisphenol C composition containing bisphenol C in a predetermined ratio.

Claims (6)

Bisphenol composition containing 95% by mass or more of bisphenol and 1% by mass or more of 2,2'-bi [1-hydroxy-4- (4-hydroxy-3-methylphenyl) dimethylmethyl] -6-methylphenyl] object. The bisphenol composition according to claim 1, which contains 2,2'-bi [1-hydroxy-4- (4-hydroxy-3-methylphenyl) dimethylmethyl] -6-methylphenyl] in an amount of 300% by mass or less. The bisphenol composition according to claim 1 or 2, wherein the bisphenol is 2,2-bis (4-hydroxy-3-methylphenyl) propane. Any of claims 1 to 3 in which 2,2'-bi [1-hydroxy-4- (4-hydroxy-3-methylphenyl) dimethylmethyl] -6-methylphenyl] is produced as a by-product in the production of bisphenol. The method for producing a bisphenol composition according to item 1. A method for producing a polycarbonate resin using the bisphenol composition according to any one of claims 1 to 3. The method for producing a polycarbonate resin according to claim 5, wherein the polycarbonate resin having a viscosity average molecular weight of 15,000 or more and 35,000 or less is produced.