JP2024016425A - Cyclic dialcohol compound and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel, high-purity cyclic dialcohol compound with improved thermal stability and optical properties and a method for producing the same.

SOLUTION: The present invention provides a cyclic dialcohol compound represented by the following formula (1) (wherein R¹ and R² each independently represent a hydrocarbon group, where neither hydrocarbon group at R¹ and R² includes an ether linkage).

SELECTED DRAWING: None

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a cyclic dialcohol compound and a method for producing the same.

Various cyclic dialcohols are used as raw materials for polyester resin, polycarbonate resin, and polyester carbonate resin, and the industrially available compound is 1,4-cyclohexanedimethanol (sometimes abbreviated as CHDM). , tricyclo[5.2.1.0 ^2,6 ]decane dimethanol (sometimes abbreviated as TCDDM), 2,2-bis(4-hydroxycyclohexyl)propane (sometimes called hydrogenated bisphenol A) ), 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane (sometimes called spiroglycol), etc. . In addition to these compounds, various cyclic dialcohol compounds have been developed depending on the use of the resin.

For example, polycarbonate resin used in optical lenses is manufactured using a dialcohol containing an aromatic dialcohol compound with a fluorene ring structure, with the aim of improving the optical properties of the resin such as transparency, heat resistance, and refractive index. has been reported (Patent Document 1), and a method for manufacturing using other cyclic dialcohols in a fixed ratio has also been reported (Patent Documents 2 and 3).

However, polyester resins, polycarbonate resins, and polyester carbonate resins are used in a wide variety of ways depending on their uses, and there is a need for the development of cyclic dialcohol compounds that can satisfy the physical properties of the resins depending on their uses. In particular, when used in optical lenses, new cyclic dialcohol compounds other than the above-mentioned cyclic dialcohols are required in recent years to improve optical properties. In recent years, cyclic diol compounds obtained by reacting diketones and trimethylol compounds under acidic catalysts (acetalization reaction) have been actively developed. Because the reaction temperature is high, hydrolysis may occur during the reaction and the thermal stability of the cyclic diol compound may decrease (Patent Document 4 and Patent Document 5). Then, when trying to polymerize a thermoplastic resin such as a polyester resin, polycarbonate resin, or polyester carbonate resin using the cyclic diol compound obtained by the manufacturing method described in Patent Document 4 or Patent Document 5, decomposition occurs during polymerization, resulting in polymerization. However, there is still room for improvement in the production method, as there are cases where it is not possible to obtain a satisfactory polymer by crosslinking starting from the decomposition point of the cyclic diol compound.

International Publication No. 2007/142149 International Publication No. 2017/175693 International Publication No. 2022/004239 JP 2019-14711 Publication International Publication No. 2022/091990

An object of the present invention is to provide a novel cyclic dialcohol compound having high purity and improved thermal stability in addition to optical properties, and a method for producing the same.

The present invention was achieved as a result of studies to solve the problems of the prior art described above, and provides a cyclic dialcohol compound that has a certain quality and is excellent as a polymer raw material, and a method for producing the same. That's true. Specifically, the present invention relates to the following cyclic dialcohol compound and its manufacturing method.

[1] A cyclic dialcohol compound represented by the following formula (1).
(In the formula, R ¹ and R ² each independently represent a hydrocarbon group. However, the hydrocarbon groups of R ¹ and R ² do not contain an ether bond.)

[2] The cyclic dialcohol compound according to the above [1], wherein R ¹ and R ² in the formula (1) are ethyl groups.
[3] The cyclic dialcohol compound according to the above [1] or [2], wherein the cyclic dialcohol compound represented by the formula (1) has a 5% weight loss temperature of 265°C or higher.
[4] The ring according to any one of [1] to [3] above, in which the content (S) of the sulfur element contained in the cyclic dialcohol compound represented by the formula (1) satisfies the following formula (2). Formula dialcohol compound.
0ppm≦S≦50ppm (2)
[5] The cyclic dialcohol compound according to any one of [1] to [4] above, wherein the cyclic dialcohol compound represented by formula (1) has a gas chromatography purity of 90 area % or more.

[6] A method for producing a cyclic dialcohol compound represented by formula (1) described in [1] above, which comprises at least Step 1 and Step 2.
Step 1: A step of reacting 4,4'-bicyclohexanone represented by the following formula (3) with a trimethylol compound represented by the following formula (4) in a reaction solvent in the presence of an acid. Step 2: Step 1 completed. A step of concentrating the reaction solution obtained after filtering off the cyclic dialcohol compound represented by formula (1) from the subsequent reaction solution, and then adding a reaction solvent and an acid again to react.
(In the formula, R ³ represents a hydrocarbon group. However, the hydrocarbon group of R ³ does not include an ether bond.)

[7] The method for producing a cyclic dialcohol compound according to [6] above, wherein the compound represented by formula (4) is trimethylolpropane.
[8] The method for producing a cyclic dialcohol compound according to [6] or [7] above, wherein 2-propanol is used as the reaction solvent used in Steps 1 and 2.
[9] The acid used in Steps 1 and 2 is a heteropolyacid composed of para-toluenesulfonic acid, phosphoric acid or silicic acid and an oxygen acid ion of at least one element selected from vanadium, molybdenum and tungsten. A method for producing a cyclic dialcohol compound according to any one of [6] to [8] above.
[10] The cyclic dialcohol compound according to any one of [1] to [5] above, which is used as a raw material for a thermoplastic resin for optical members.

According to the present invention, a highly purified cyclic dialcohol compound with excellent thermal stability can be synthesized in high yield, and the optical properties of a thermoplastic resin using the compound can be improved.

¹ H NMR of 4,4'-dioxohydroxyl-bis(trimethylolpropane) acetal obtained in Step 1 of Example 1.

Although the present invention will be described in detail, the explanation of the constituent elements described below is a representative example of the embodiment of the present invention, and the present invention is not limited to these contents.

[Cyclic dialcohol compound]
The cyclic dialcohol compound of the present invention is a cyclic dialcohol compound represented by the following formula (1).
(In the formula, R ¹ and R ² each independently represent a hydrocarbon group. However, the hydrocarbon groups of R ¹ and R ² do not contain an ether bond.)

In the above formula (1), examples of the hydrocarbon groups represented by R ¹ and R ² include an alkyl group and a cycloalkyl group. Among these, alkyl groups are particularly preferred. Specific examples of the alkyl group include alkyl groups having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, and t-butyl; is more preferred, an alkyl group having 1 to 3 carbon atoms is even more preferred, and an ethyl group is particularly preferred.

Representative examples of the cyclic dialcohol compound represented by the above formula (1) are shown below, but the raw materials used in the above formula (1) of the present invention are not limited thereto.

These may be used alone or in combination of two or more. Among them, the following formula (1-a) and the following formula (1-b) are more preferred, and the following formula (1-b) is particularly preferred.

The 5% weight loss temperature of the cyclic dialcohol compound of the present invention is the 5% weight loss temperature at a heating rate of 20°C/min in a nitrogen atmosphere, preferably 265°C or higher, and more preferably 275°C or higher. The temperature is preferably 285°C or higher, more preferably 295°C or higher, and most preferably 300°C or higher. When the 5% weight loss temperature is equal to or higher than the above lower limit, the cyclic dialcohol compound of the present invention can be polymerized without being decomposed at the stage of polymerizing the thermoplastic resin. On the other hand, if the 5% weight loss temperature is lower than the above lower limit, the cyclic dialcohol compound of the present invention will decompose and cannot be polymerized at the stage of polymerizing the thermoplastic resin, or the decomposed product will be crosslinked and gelled. There is a possibility that it will be stored away.

In the cyclic dialcohol compound of the present invention, the content (S) of sulfur element preferably satisfies the following formula (2).
0ppm ≦ S ≦ 50ppm (2)
More preferably, the following formula (2-1) is satisfied.
0ppm ≦ S ≦ 40ppm (2-1)
More preferably, the following formula (2-2) is satisfied.
0ppm ≦ S ≦ 30ppm (2-2)
Even more preferably, the following formula (2-3) is satisfied.
0ppm ≦ S ≦ 20ppm (2-3)
Particularly preferably, the following formula (2-4) is satisfied.
0ppm ≦ S ≦ 10ppm (2-4)
Most preferably, the following formula (2-5) is satisfied.
0ppm ≦ S ≦ 5ppm (2-5)

When the upper limit of the above range is exceeded, the cyclic dialcohol compound represented by the formula (1) is likely to be hydrolyzed and the 5% weight loss temperature may decrease. The lower limit of the content of the sulfur element may be 0.01 ppm or more, 0.05 ppm or more, or 0.10 ppm or more.

The cyclic dialcohol compound of the present invention preferably has a purity measured by gas chromatography of 90 area % or more, more preferably 95 area % or more, even more preferably 98 area % or more, It is particularly preferable that the area is 99% by area or more.

[Method for producing cyclic dialcohol compound]
As a method for producing the cyclic dialcohol compound represented by the above formula (1) of the present invention, it can be obtained by acetalizing bicyclohexanone and a trimethylol compound.
Specifically, as a method for producing the cyclic dialcohol compound represented by the above formula (1) of the present invention, a production method comprising at least the following steps 1 and 2 is preferably mentioned.

That is, from step 1 in which 4,4'-bicyclohexanone represented by the following formula (3) and a trimethylol compound represented by the following formula (4) are reacted, and the reaction liquid generated in step 1, the above formula (1 ) After concentrating the reaction solution obtained after filtering off the cyclic dialcohol compound represented by ), it can be produced by Step 2 in which unreacted 4,4'-bicyclohexanone and a trimethylol compound are reacted once again. In the production method of the present invention, the reaction temperature is low in both steps, so hydrolysis does not occur during the reaction, the acid can be easily separated, and step 2 requires only repeating the same operation using the reaction liquid generated in step 1. Further, since both steps do not require purification steps such as recrystallization, the cyclic dialcohol compound of the present invention can be produced very simply and efficiently.
(In the formula, R ³ represents a hydrocarbon group. However, the hydrocarbon group of R ³ does not include an ether bond.)

The purity of 4,4'-bicyclohexanone represented by the above formula (3) is not particularly limited, but is usually preferably 90% or more, more preferably 98% or more. Note that 4,4'-bicyclohexanone as shown in the above formula (3) may be a commercially available product, or may be synthesized in advance. For example, as a method for producing 4,4'-bicyclohexanone, referring to the method described in a non-patent document (Angewandte Chemie, International Edition, 2012, Vol. 51, 12790-12794), 4,4'-bicyclohexanone is Examples include a method in which hexanol and an iridium catalyst are reacted under reflux of the reaction solvent.

The compound represented by the above formula (4) is a compound corresponding to the dialcohol in the above formula (1), and R ³ corresponds to R ¹ and R ² represented by the above formula (1). However, the hydrocarbon group of R ³ does not contain an ether bond.

Representative examples of the trimethylol compound represented by formula (4) are shown below, but the raw materials used in formula (1) of the present invention are not limited thereto.
Specifically, trimethylol ethane, trimethylol propane, trimethylol butane, trimethylol-(2,2'-dimethyl)-propane, trimethylol pentane, trimethylol isopentane, trimethylol hexane, trimethylol heptane, trimethylol octane. etc. are preferably mentioned. Among these, trimethylolethane and trimethylolpropane are more preferred, and trimethylolpropane is even more preferred.

The purity of the trimethylol compound represented by the formula (4) used is not particularly limited, but is usually preferably 95% or more, more preferably 98% or more.

The usage ratio of the trimethyl compound represented by the formula (4) used as a raw material is preferably 1.5 to 5 to 1 mole of the compound (4,4'-bicyclohexanone) represented by the formula (3). It may be in the range of moles, more preferably 2.0 to 3.0 moles, even more preferably 2.1 to 2.5 moles. If the alcohol content is less than the above lower limit, the yield of the product represented by the formula (1) may be low. Moreover, when the above upper limit is exceeded, although the reaction rate is fast and the yield is high, the manufacturing cost of the cyclic dialcohol compound may increase.

The reaction (acetalization) between 4,4'-bicyclohexanone represented by the above formula (3) and the trimethylol compound represented by the above formula (4) in Steps 1 and 2 is performed using an acid in the reaction solvent. It can be done in the presence of

The acids used in the reactions in Steps 1 and 2 include mineral acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid, paratoluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, trifluoroacetic acid, and trifluoromethanesulfonic acid. Examples include organic acids, cation exchange resins, zeolites, solid acids such as heteropolyacids (for example, phosphotungstic acid, phosphomolybdic acid, etc.), and other various Lewis acids. Among these, organic acids and solid acids are preferred, and heteropolyacids composed of para-toluenesulfonic acid, phosphoric acid, or silicic acid and an oxyacid ion of at least one element selected from vanadium, molybdenum, and tungsten are more preferred; Toluenesulfonic acid (organic acid) and phosphotungstic acid (solid acid) are particularly preferred. These may be used alone or in combination of two or more.

The amount of acid used is usually preferably 0.001 to 20% by weight, more preferably 0.05 to 15% by weight, even more preferably 0.5 to 10% by weight, based on the trimethylol compound of formula (4). % by weight.

Examples of the reaction solvent used in Steps 1 and 2 include aromatic hydrocarbon solvents such as toluene and xylene, and alcohols such as methanol, ethanol, isopropyl alcohol (hereinafter referred to as 2-propanol), and n-butanol. can be used. Among these, alcohols are preferred from the viewpoint of thermal stability of the cyclic dialcohol compound represented by formula (1), and 2-propanol is particularly preferred. When an aromatic hydrocarbon solvent such as toluene is used, the reaction temperature can be set high and by-product water can be efficiently removed, but hydrolysis reaction also occurs simultaneously during the reaction, resulting in a loss of 5% of the target product. The weight loss temperature may drop.

The amount of the reaction solvent used in Steps 1 and 2 is not particularly limited, but is preferably at least 3 times the theoretical yield of the cyclic dialcohol compound (target product) represented by the formula (1). , more preferably 4 to 9 times by weight, still more preferably 5 to 10 times by weight. If the amount of the reaction solvent used is less than the above lower limit, stirring may become difficult when the target product precipitates during the reaction. In addition, when the amount of solvent used in the reaction exceeds 10 times by weight, the reaction rate is slow and there is no effect commensurate with the amount used, and the volumetric efficiency deteriorates, which may increase the manufacturing cost of the cyclic dialcohol compound.

The reaction temperature in Steps 1 and 2 varies depending on the type of raw materials and solvent used, but is preferably 20 to 80°C, more preferably 20 to 60°C, and still more preferably 20 to 40°C. Reaction temperature If the temperature is lower than the above lower limit, the reaction rate may be slow and the yield may be reduced. In addition, if the above upper limit is exceeded, the reaction rate becomes faster, but the cyclic dialcohol compound represented by the formula (1) is hydrolyzed during the reaction by the water produced as a by-product, and the 5% weight loss temperature also decreases. Sometimes I put it away. The reaction can be followed by analytical means such as gas chromatography.

The reaction mixture after completion of the reactions in Steps 1 and 2 usually contains unreacted 4,4'-dicyclohexanone and trimethylol compounds in addition to the generated cyclic dialcohol compound represented by formula (1). , acids, side reaction products, by-product water, etc. Therefore, it can be separated and purified by conventional methods, such as separation means such as neutralization, filtration, concentration, crystallization, recrystallization, reprecipitation, column chromatography, or a combination of these methods. For example, by neutralizing the acid using a conventional method (method of neutralizing by adding an alkaline aqueous solution such as sodium hydroxide or sodium bicarbonate), and removing trimethylol compounds and side reaction products by crystallization, the desired product can be obtained. The cyclic dialcohol compound of formula (1) may be precipitated and then purified by filtration.

The gas chromatography purity of the cyclic dialcohol compound obtained by the production method of the present invention can be selected from a wide range of 60 to 100 area%, preferably 80 area% or more, 90 area% or more, 95% area or more, 98% area% or more. area% or more, and 99 area% or more.

[Characteristics and uses of cyclic dialcohol compounds]
The cyclic dialcohol compound of the present invention can be used as a raw material (monomer) for various resins. For example, monomers of thermoplastic resins (e.g., polyester resins, polycarbonate resins, polyester carbonate resins, polyurethane resins, etc.), and thermosetting resins (e.g., epoxy resins, phenolic resins, thermosetting polyurethane resins, (meth)acrylates ( (meth)acrylic acid ester), etc.). In particular, polyester resins, polycarbonate resins, and polyester carbonate resins are typical.

When the cyclic dialcohol compound of the present invention is used as a polyol component, the resulting resin has the advantage of having both high thermal stability and optical properties at a high level, probably because it has a cyclic skeleton. In particular, the cyclic dialcohol compound of the present invention is preferably used as a raw material for thermoplastic resins for optical members.

Hereinafter, the present invention will be explained in detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.
In addition, in the examples, various measurements were performed as follows.

(1) ¹ H NMR measurement The compounds obtained in the examples were measured using the following equipment and solvent.
Equipment: JNM-AL400 (400MHz) manufactured by JEOL Ltd.
Solvent: _CDCl3

(2) Gas chromatography measurement (GC/MS)
Measurement was performed using a single quadrupole GC/MS 5977B manufactured by Agilent Technologies under the following measurement conditions. In the examples, unless otherwise specified, purity (%) is an area percentage value corrected by excluding the solvent in GC/MS.
(GC)
Column: DB-1 (inner diameter 0.25 mm, length 30 m, film thickness 0.25 μm)
Injection volume: 1μl
Injection method: split ratio 40:1
Inlet temperature: 280℃
Oven: 60℃ - 10℃/min - 280℃ (28 minutes)
Carrier gas: He, linear velocity 36.6 cm/s
(MS)
Ion source temperature: 230℃
Ionization mode: EI 70eV
Measurement range: m/z 33-700

(3) Combustion ion chromatography measurement The content of sulfur element (S amount) was measured using the automatic sample combustion device AQF-2100 manufactured by Mitsubishi Chemical and the ion chromatography system DIONEX AQUION manufactured by Thermo Fisher under the following measurement conditions. . The calibration curve was created using a sulfate ion standard solution (SO4(2-):1000) manufactured by Fujifilm Wako Pure Chemical Industries.
Measurement temperature: 900℃→1000℃
Absorption liquid: Ultrapure water containing hydrogen peroxide Column: AS-17/AG-17
Flow rate: 1ml/min
Cell temperature: 40℃, column temperature: 35℃

(4) 5% Weight Loss Temperature The obtained resin was measured at a heating rate of 20°C/min in a nitrogen atmosphere using a differential thermal/thermogravimetric simultaneous measurement device Discovery SDT650 manufactured by TA Instruments. The decreasing temperature was measured. The sample was measured at approximately 5 mg.

(5) Refractive index (nD)
The resin obtained in the example was measured using the following apparatus and method.
Equipment: KRP-2000 manufactured by Shimadzu Corporation
Method: A 3 mm thick test piece of the resin obtained after completion of polymerization was prepared and polished.

(6) Abbe number measurement The Abbe number was calculated from the refractive index at wavelengths of 486.13 nm, 587.56 nm, and 656.27 nm using the following formula.
ν=(nD-1)/(nF-nC)
In the present invention, nD: refractive index at a wavelength of 587.56 nm;
nC: refractive index at a wavelength of 656.27 nm,
nF: means the refractive index at a wavelength of 486.13 nm.

(7) Glass transition temperature (Tg)
The obtained resin was measured at a heating rate of 20° C./min using a differential thermal/thermogravimetric simultaneous measuring device Discovery SDT650 manufactured by TA Instruments. The sample was measured at approximately 5 mg.

[Example 1]
<Step 1>
After adding 25 g (129 mmol) of 4,4'-bicyclohexanone, 36 g (270 mmol) of trimethylolpropane, and 200 mL of 2-propanol to a flask equipped with a stirrer, a condenser, and a thermometer, 250 mL of 2-propanol was added. 1.47 g (8 mmol) of para-toluenesulfonic acid dissolved in water was added slowly dropwise. The mixture was stirred overnight at room temperature to complete the reaction. A white solid was precipitated, but it was neutralized by adding sodium hydroxide, and the precipitated white crystals were collected by filtration to obtain the target product, 4,4'-dioxohydroxyl-bis(trimethylolpropane) acetal (hereinafter referred to as , sometimes abbreviated as BCHPA) was obtained in a yield of 62% in an amount of 34 g. The obtained BCHPA was analyzed by ¹ H NMR and confirmed to be the target product (FIG. 1). Moreover, when gas chromatography was measured, the purity was 99.7%, and when the amount of residual sulfur was measured by ion chromatography, it was 0.4 ppm. Furthermore, when the 5% weight loss temperature was measured, it was 305°C.

<Step 2>
After concentrating the filtrate generated in Step 1, 2-propanol and para-toluenesulfonic acid were added and the mixture was stirred at room temperature overnight to complete the reaction. A white solid was precipitated, but sodium hydroxide was added thereto to neutralize it, and the precipitated white crystals were collected by filtration to obtain 11 g of a white solid of BCHPA, the target product, in a yield of 20%. When measured by gas chromatography, the purity was 99.7%, and when the amount of residual sulfur was measured by ion chromatography, it was 3.1 ppm. Furthermore, when the 5% weight loss temperature was measured, it was 309°C.

<Step 3>
4.3 parts by mass (20 mol%) of BCHPA obtained in Step 1 and Step 2, 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (hereinafter sometimes abbreviated as BPEF) 17. 54 parts by mass (80 mol%), 10.82 parts by mass (101 mol%) of diphenyl carbonate (hereinafter sometimes abbreviated as DPC), and 2.10×10 sodium hydrogen carbonate at a concentration of 60 mmol/L as a catalyst. ^-4 parts by mass (5.00 × 10 ^-3 mol%) and 1.37 × 10 ^-3 parts by mass (3.01 × 10 ^-2 mol%) of tetramethylammonium hydroxide were added at a concentration of 274 mmol/L. , and was heated to 180° C. in a nitrogen atmosphere to melt it. Thereafter, the degree of pressure reduction was adjusted to 20 kPa over a period of 5 minutes. The temperature was raised to 240 °C at a temperature increase rate of 40 °C/hr, and after the outflow amount of phenol reached 70%, the degree of vacuum was reduced to 1 kPa, and the polymerization reaction was carried out until the predetermined power was reached. After completion, the resin was taken out from the flask. The obtained polycarbonate resin was analyzed by 1H NMR, and it was confirmed that the BCHPA component was introduced in an amount of 20 mol% based on the total monomer components, and the BPEF component was introduced in an amount of 80 mol% based on the total monomer components. The obtained polycarbonate resin had a refractive index of 1.613, an Abbe number of 26.3, a Tg of 145°C, and a 5% weight loss temperature of 378°C.

[Example 2]
<Step 1>
A white solid of BCHPA was obtained in the same manner as in Example 1 <Step 1> except that para-toluenesulfonic acid was changed to phosphotungstic acid (dehydrated in advance) (yield 60%, purity 99.1%). . The amount of residual sulfur was measured by ion chromatography and was found to be 0 ppm. Furthermore, when the 5% weight loss temperature was measured, it was 305°C.

<Step 2>
A white solid of BCHPA was obtained in the same manner as in Example 1 <Step 2> except that para-toluenesulfonic acid was changed to phosphotungstic acid (pre-dehydrated) (yield 20%, purity 99.2%). . The amount of residual sulfur was measured by ion chromatography and was found to be 0 ppm. Furthermore, when the 5% weight loss temperature was measured, it was 306°C.

[Reference example 1]
<Step 1>
In a 1 L flask equipped with a stirrer, a water separator with a condenser, and a thermometer, add 40 g (206 mmol) of bicyclohexanone, 58 g (432 mmol) of trimethylolpropane, 1.17 g (6 mmol) of paratoluenesulfonic acid, and toluene. After adding 415 mL, the reaction was completed by stirring for 6 hours while refluxing toluene at 115° C. to perform azeotropic dehydration under a nitrogen stream. After the reaction was completed, the reaction solution was cooled to room temperature and crystals precipitated, but the reaction solution was then neutralized with sodium hydroxide. The precipitated white crystals were collected by filtration to obtain 83 g of a white solid of BCHPA, the target product, in a yield of 94%. When measured by GC, the purity was 99.0%, and when the amount of residual sulfur was measured by ion chromatography, it was 54.3 ppm. Furthermore, when the 5% weight loss temperature was measured, it was 236°C.

<Step 2>
An attempt was made to polymerize a polycarbonate resin in the same manner as in <Step 3> of Example 1 except that the BCHPA obtained in <Step 1> of Reference Example 1 was used, but BCHPA decomposed and polymerized during the polymerization. I couldn't.

Examples of the resin using the cyclic dialcohol compound of the present invention as a raw material (monomer) include films, lenses, prisms, optical disks, transparent conductive substrates, optical cards, sheets, optical fibers, optical films, optical filters, hard coat films, etc. It can be used for optical members, and is particularly useful for lenses.

Claims (10)

A cyclic dialcohol compound represented by the following formula (1).
(In the formula, R ¹ and R ² each independently represent a hydrocarbon group. However, the hydrocarbon groups of R ¹ and R ² do not contain an ether bond.) The cyclic dialcohol compound according to claim 1, wherein R ¹ and R ² in the formula (1) are ethyl groups. The cyclic dialcohol compound according to claim 1, wherein the cyclic dialcohol compound represented by formula (1) has a 5% weight loss temperature of 265°C or higher. The cyclic dialcohol compound according to claim 1, wherein the content (S) of sulfur element contained in the cyclic dialcohol compound represented by the formula (1) satisfies the following formula (2).
0ppm≦S≦50ppm (2) The cyclic dialcohol compound according to claim 1, wherein the cyclic dialcohol compound represented by the formula (1) has a gas chromatography purity of 90 area % or more. A method for producing a cyclic dialcohol compound represented by formula (1) according to claim 1, comprising at least Step 1 and Step 2.
Step 1: A step of reacting 4,4'-bicyclohexanone represented by the following formula (3) with a trimethylol compound represented by the following formula (4) in a reaction solvent in the presence of an acid. Step 2: Step 1 completed. A step of concentrating the reaction solution obtained after filtering off the cyclic dialcohol compound represented by formula (1) from the subsequent reaction solution, and then adding a reaction solvent and an acid again to react.
(In the formula, R ³ represents a hydrocarbon group. However, the hydrocarbon group of R ³ does not include an ether bond.) 7. The method for producing a cyclic dialcohol compound according to claim 6, wherein the compound represented by formula (4) is trimethylolpropane. 7. The method for producing a cyclic dialcohol compound according to claim 6, wherein 2-propanol is used as the reaction solvent used in steps 1 and 2. A claim in which the acid used in steps 1 and 2 is a heteropolyacid composed of para-toluenesulfonic acid, phosphoric acid, or silicic acid, and an oxyacid ion of at least one element selected from vanadium, molybdenum, and tungsten. 6. The method for producing a cyclic dialcohol compound according to 6. The cyclic dialcohol compound according to any one of claims 1 to 5, which is used as a raw material for a thermoplastic resin for optical members.