TW202028161A - Method for producing crystal of cyclohexane tricarboxylic acid anhydride, and crystal - Google Patents
Method for producing crystal of cyclohexane tricarboxylic acid anhydride, and crystal Download PDFInfo
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本發明係關於環己烷三羧酸酐之結晶之製造方法及結晶。The present invention relates to a method for producing the crystal of cyclohexane tricarboxylic acid anhydride and the crystal.
環己烷三羧酸酐已知作為塗料、黏接劑、成形品、半導體之密封劑用樹脂、熱硬化性樹脂組成物之硬化劑、聚醯亞胺樹脂、聚醯胺醯亞胺樹脂、聚醯胺樹脂、聚酯樹脂、醇酸樹脂等原料、改質劑或改性劑、塑化劑、潤滑油原料、醫農藥中間體、塗料用樹脂原料、色劑用樹脂等有用。Cyclohexane tricarboxylic acid anhydride is known as coatings, adhesives, molded products, semiconductor sealant resins, thermosetting resin composition hardeners, polyimide resins, polyimide imide resins, and polyimide resins. Raw materials such as amido resins, polyester resins, and alkyd resins, modifiers or modifiers, plasticizers, lubricating oil raw materials, medical and agricultural intermediates, resin raw materials for paints, resins for colorants, etc. are useful.
專利文獻1記載了環己烷三羧酸酐之結晶。具體而言，揭示一種trans,trans-1,2,4-環己烷三羧酸-1,2-酐之製造方法，特徵為係利用使用了水的晶析，從cis,cis-1,2,4-環己烷三羧酸與trans,trans-1,2,4-環己烷三羧酸之混合物分離出trans,trans-1,2,4-環己烷三羧酸。
[先前技術文獻]
[專利文獻]
[專利文獻1]日本特開2013-056856號公報[Patent Document 1] JP 2013-056856 A
(發明欲解決之課題)(Problems to be solved by the invention)
在此，製造環己烷三羧酸酐之結晶時，考量使成為原料之溶解狀態之環己烷三羧酸酐於一元羧酸存在下冷卻並使其晶析。並且，通常係於晶析後將固體與液體分離，使獲得之結晶(濕晶)乾燥，而獲得結晶(乾晶)。但是濕晶會於結晶之表面殘留液體，尤其若大量生產環己烷三羧酸酐之結晶時，若濕晶之表面的液體多則會有以下之問題。 亦即，將濕晶加熱使其乾燥時，若表面有多量溶劑附著，則於乾燥中，基質對溶劑之溶解會進行。如此，濕晶的粉體會成為大型塊體。且伴隨濕晶之表面積減少，乾燥效率會顯著下降，而且獲得之乾晶(乾燥品)會變成大型塊狀體，故操作性也下降。 為了避免如上述不良情形，有人考慮於低溫乾燥的方式，但於低溫乾燥的話，乾燥速度下降，因而生產性降低。 故為了減輕上述問題，使濕晶之含液率下降是非常重要的項目。 本發明為了解決該課題，目的在於提供獲得於濕晶狀態時之表面液體量少之結晶之環己烷三羧酸酐之結晶之製造方法，及提供環己烷三羧酸酐之結晶。 (解決課題之方式)Here, when manufacturing the crystals of cyclohexanetricarboxylic acid anhydride, it is considered that the cyclohexanetricarboxylic acid anhydride in the dissolved state of the raw material is cooled and crystallized in the presence of a monocarboxylic acid. Furthermore, it is usually based on separating the solid from the liquid after crystallization, and drying the obtained crystal (wet crystal) to obtain the crystal (dry crystal). However, the wet crystal will leave liquid on the surface of the crystal, especially if the crystals of cyclohexanetricarboxylic anhydride are produced in large quantities, if there is a lot of liquid on the surface of the wet crystal, the following problems will occur. That is, when the wet crystal is heated and dried, if a large amount of solvent adheres to the surface, the dissolution of the solvent by the matrix will proceed during drying. In this way, the wet crystal powder will become a large block. And as the surface area of the wet crystal decreases, the drying efficiency will be significantly reduced, and the obtained dry crystal (dried product) will become a large block, so the operability will also decrease. In order to avoid the above-mentioned disadvantages, some people consider low-temperature drying. However, when drying at low temperature, the drying speed decreases and productivity decreases. Therefore, in order to alleviate the above problems, it is very important to reduce the liquid content of the wet crystal. In order to solve this problem, the purpose of the present invention is to provide a method for producing a crystal of cyclohexanetricarboxylic acid anhydride with a small amount of surface liquid in a wet crystal state, and to provide a crystal of cyclohexanetricarboxylic acid anhydride. (The way to solve the problem)
於此狀況下，本案發明人研究之結果，利用下列手段解決了上述課題。
>1>一種環己烷三羧酸酐之結晶之製造方法，包括使環己烷三羧酸酐於存在有含有0~100質量%之於20℃為液體之一元羧酸及100~0質量%之該於20℃為液體之一元羧酸之酸酐的溶劑(惟該一元羧酸與一元羧酸酐之合計不超過100質量%)之晶析系進行晶析之步驟，
該晶析系於晶析開始時含有來自環己烷三羧酸酐晶析後之母液之成分，
包括添加各成分以使該晶析系晶析開始時之組成成為相對於超過0.20質量份且1.00質量份以下之下式(1)表示之化合物，該環己烷三羧酸酐係5.0~49.9質量份且該溶劑係50~95.0質量份之比例之步驟，
且包括使該晶析系冷卻而使其晶析之步驟；
式(1)
依本發明，可提供能獲得於濕晶狀態時之表面液體量少之結晶之環己烷三羧酸酐之結晶之製造方法、及環己烷三羧酸酐之結晶。According to the present invention, it is possible to provide a method for producing a crystal of cyclohexanetricarboxylic acid anhydride and a crystal of cyclohexanetricarboxylic acid anhydride that can obtain crystals with a small amount of surface liquid when in a wet crystal state.
以下針對本發明之內容詳細說明。又，本說明書中，「~」係使用在包括其前後記載之數值作為下限值及上限值之意。
本發明之環己烷三羧酸酐之結晶之製造方法，包括使環己烷三羧酸酐於存在有含有0~100質量%之於20℃為液體之一元羧酸及100~0質量%之該於20℃為液體之一元羧酸之酸酐的溶劑(惟該一元羧酸與一元羧酸酐之合計不超過100質量%)之晶析系進行晶析之步驟，
該晶析系於晶析開始時含有來自環己烷三羧酸酐晶析後之母液之成分，
包括添加各成分以使該晶析系晶析開始時之組成成為相對於超過0.20質量份且1.00質量份以下之下式(1)表示之化合物，該環己烷三羧酸酐係5.0~49.9質量份且該溶劑係50~95.0質量份之比例之步驟，
且包括使該晶析系冷卻而使其晶析之步驟；
式(1)
藉由為如此的構成，能使獲得之濕晶中之含液率為低。 在此，濕晶係指進行晶析並和母液分離後，乾燥前之結晶，和乾燥後之結晶即乾晶有區別。又，本發明中，結晶若無特別指明，係包括濕晶及乾晶兩者之意。 本發明之結晶之製造方法獲得之結晶，於濕晶狀態之含液率低。所以，能避免上述問題。又，就獲得之結晶含有一定量之MeHHPA這一點，與以往有若干差異。 以下依圖1所示方案，針對本發明之結晶之製造方法說明。又，當然，下列步驟在本發明之製造方法中不是全都必要。With such a configuration, the liquid content in the obtained wet crystal can be low. Here, wet crystal refers to the crystallization before drying after crystallization and separation from the mother liquor, which is different from the crystallization after drying, that is, the dry crystal. In the present invention, unless otherwise specified, crystal includes both wet crystal and dry crystal. The crystal obtained by the crystal manufacturing method of the present invention has a low liquid content in the wet crystal state. Therefore, the above-mentioned problems can be avoided. In addition, the obtained crystal contains a certain amount of MeHHPA, which is slightly different from the past. The following describes the method for manufacturing the crystal of the present invention according to the scheme shown in FIG. 1. Also, of course, not all the following steps are necessary in the manufacturing method of the present invention.
>獲得環己烷三羧酸酐之步驟(酸酐化步驟)> 獲得晶析前之環己烷三羧酸酐之方法可採用公知之方法。就一理想實施形態而言，可列舉如圖1，將環己烷三羧酸(H-TMA)添加到含有於20℃為液體之一元羧酸(例如：乙酸)0~100質量%與於20℃為液體之一元羧酸之酸酐(例如：乙酸酐)100~0質量%之溶劑(惟一元羧酸與一元羧酸酐之合計不超過100質量%)，而獲得環己烷三羧酸酐之形態。>Step to obtain cyclohexane tricarboxylic acid anhydride (acid anhydride step)> The method for obtaining the cyclohexanetricarboxylic acid anhydride before crystallization can adopt a known method. For an ideal embodiment, as shown in Figure 1, cyclohexanetricarboxylic acid (H-TMA) is added to a liquid monocarboxylic acid (for example: acetic acid) containing 0-100% by mass at 20°C. 20 ℃ is a liquid monocarboxylic acid anhydride (for example: acetic anhydride) 100~0 mass% solvent (only the total of monocarboxylic acid and monocarboxylic anhydride does not exceed 100 mass%), and the cyclohexane tricarboxylic anhydride is obtained form.
環己烷三羧酸宜為環己烷-1,2,4-三羧酸較佳。 該等環己烷三羧酸為順式體、反式體、混合物皆可。本發明中，至少含有順式體較佳，環己烷三羧酸之90質量%以上為順式體較佳。Cyclohexane tricarboxylic acid is preferably cyclohexane-1,2,4-tricarboxylic acid. These cyclohexane tricarboxylic acids are available in cis form, trans form, and mixtures. In the present invention, at least the cis isomer is preferably contained, and 90% by mass or more of the cyclohexanetricarboxylic acid is preferably the cis isomer.
溶劑，如上述，宜含有於20℃為液體之一元羧酸0~100質量%及於20℃為液體之一元羧酸之酸酐100~0質量%較佳。溶劑宜含有一元羧酸50~100質量%及於20℃為液體之一元羧酸之酸酐0~50質量%較佳，含有一元羧酸60~90質量%及於20℃為液體之一元羧酸之酸酐10~40質量%更佳。 就於20℃為液體之一元羧酸而言可列舉乙酸、丙酸，乙酸為較佳。 就於20℃為液體之一元羧酸之酸酐而言，為上述一元羧酸之酸酐(一元羧酸酐)為較佳。尤其一元羧酸與一元羧酸之酸酐組合時，一元羧酸之酸酐係併用之一元羧酸之酸酐較佳。 一元羧酸之酸酐可列舉乙酸酐、丙酸酐，乙酸酐為較佳。The solvent, as described above, preferably contains 0-100% by mass of monocarboxylic acid which is liquid at 20°C and 100-0% by mass of anhydride which is liquid monocarboxylic acid at 20°C. The solvent should preferably contain 50-100% by mass of monocarboxylic acid and 0-50% by mass of anhydride which is liquid monocarboxylic acid at 20°C, preferably 60~90% by mass of monocarboxylic acid and liquid monocarboxylic acid at 20°C The acid anhydride is preferably 10-40% by mass. As for the monocarboxylic acid which is liquid at 20°C, acetic acid and propionic acid are mentioned, and acetic acid is preferred. In terms of anhydrides of monocarboxylic acids that are liquid at 20°C, anhydrides of the above-mentioned monocarboxylic acids (monocarboxylic anhydrides) are preferred. Especially when combining monocarboxylic acid and monocarboxylic acid anhydride, it is preferable to use monocarboxylic acid anhydride in combination. The anhydrides of monocarboxylic acids include acetic anhydride and propionic anhydride, with acetic anhydride being preferred.
本發明中，進行環己烷三羧酸之酸酐化時，可含有也可不含有一元羧酸及一元羧酸酐以外之其他溶劑。含有其他溶劑時，可列舉沸點50℃以上之烴系溶劑、鹵化烴系溶劑、酯系溶劑、酮系溶劑、醚系溶劑、脂肪酸系溶劑。含有其他溶劑時，其含量相對於一元羧酸及一元羧酸酐之合計為1~100質量%較佳。又，本發明中，也可為實質不含一元羧酸及一元羧酸酐以外之其他溶劑之構成。實質不含，係指其他溶劑未達溶劑全量之1質量%，0.1質量%以下較佳，0.05質量%以下更佳。In the present invention, when the cyclohexanetricarboxylic acid is anhydride, it may or may not contain other solvents other than monocarboxylic acid and monocarboxylic anhydride. When other solvents are contained, hydrocarbon-based solvents, halogenated hydrocarbon-based solvents, ester-based solvents, ketone-based solvents, ether-based solvents, and fatty acid-based solvents having a boiling point of 50°C or higher can be cited. When other solvents are contained, the content is preferably 1 to 100% by mass relative to the total of monocarboxylic acid and monocarboxylic anhydride. In addition, in the present invention, it may be a configuration that does not substantially contain other solvents other than monocarboxylic acid and monocarboxylic anhydride. Substantially free means that other solvents do not reach 1% by mass of the total amount of the solvent, preferably 0.1% by mass or less, and more preferably 0.05% by mass or less.
為了環己烷三羧酸之酸酐化，相對於環己烷三羧酸100質量份，前述溶劑合計為200~800質量份較佳，300~700質量份更佳。藉由為如此的範圍，利用晶析操作獲得之製品之純度及產率皆能提高。 本發明中，針對環己烷三羧酸、一元羧酸、一元羧酸之酸酐、其他溶劑，可分別僅使用1種，也可使用2種以上。使用2種以上時，合計量成為上述範圍較佳。In order to anhydride cyclohexanetricarboxylic acid, the total amount of the aforementioned solvents is preferably 200 to 800 parts by mass, more preferably 300 to 700 parts by mass relative to 100 parts by mass of cyclohexanetricarboxylic acid. By being in such a range, the purity and yield of the product obtained by the crystallization operation can be improved. In the present invention, for cyclohexane tricarboxylic acid, monocarboxylic acid, monocarboxylic acid anhydride, and other solvents, only one type may be used, or two or more types may be used. When two or more types are used, the total amount is preferably in the above range.
環己烷三羧酸進行酸酐化時，宜於已添加母液之狀態進行酸酐化反應較佳。母液之量，只要是調整成後述晶析步驟開始時，晶析系中含有的量會成為相對於式(1)表示之化合物超過0.20質量份且1.00質量份以下，環己烷三羧酸酐為5.0~49.9質量份及前述溶劑為50~95.0質量份之比例即可，並無特殊限定。When cyclohexane tricarboxylic acid is anhydride, it is better to perform anhydride reaction in a state where the mother liquor has been added. As long as the amount of mother liquor is adjusted so that when the crystallization step described later starts, the amount contained in the crystallization system will be more than 0.20 parts by mass and 1.00 parts by mass or less relative to the compound represented by formula (1). Cyclohexanetricarboxylic anhydride is The ratio of 5.0 to 49.9 parts by mass and the aforementioned solvent is 50 to 95.0 parts by mass, and there is no particular limitation.
環己烷三羧酸進行酸酐化時，溫度升溫成穩定狀態後之溫度(反應溫度)為80~150℃較佳，90~140℃更佳，95~130℃尤佳。又，環己烷三羧酸進行酸酐化時宜攪拌較佳。又，成為穩定狀態後之反應時間為10分鐘~4小時較理想，1~3小時更理想。 酸酐化時，可使用或不使用觸媒。使用觸媒時，可列舉分子篩。When cyclohexane tricarboxylic acid is anhydride, the temperature (reaction temperature) after the temperature is increased to a stable state is preferably 80-150°C, more preferably 90-140°C, and particularly preferably 95-130°C. In addition, it is preferable to stir when cyclohexanetricarboxylic acid is anhydride. In addition, the reaction time after reaching a stable state is preferably 10 minutes to 4 hours, and more preferably 1 to 3 hours. During acid anhydride, catalysts can be used or not. When using a catalyst, molecular sieves can be cited.
環己烷三羧酸之脫水率為90質量%以上較佳，93質量%以上更佳。脫水率依後述實施例記載的方法測定。The dehydration rate of cyclohexanetricarboxylic acid is preferably 90% by mass or more, more preferably 93% by mass or more. The dehydration rate is measured according to the method described in the examples described later.
>晶析步驟> 本發明中，包括使環己烷三羧酸酐於存在有含有0~100質量%之於20℃為液體之一元羧酸及100~0質量%之該於20℃為液體之一元羧酸之酸酐的溶劑(惟該一元羧酸與一元羧酸酐之合計不超過100質量%)之晶析系進行晶析之步驟。 該晶析系於晶析開始時含有來自環己烷三羧酸酐晶析後之母液之成分， 包括添加各成分以使該晶析系晶析開始時(以下有時稱為「初始狀態」)之組成成為相對於超過0.20質量份且1.00質量份以下之下式(1)表示之化合物，該環己烷三羧酸酐係5.0~49.9質量份且該溶劑係50~95.0質量份之比例之步驟，並且使前述晶析系冷卻而使其晶析。通常將上述酸酐化步驟後之反應液直接冷卻。藉由如此的構成，能夠使濕結晶之含液率低。 本發明之晶析系，於初始狀態含有來自母液之成分、式(1)表示之化合物、環己烷三羧酸酐、溶劑。惟式(1)表示之化合物、環己烷三羧酸酐及溶劑的一部分也可為來自母液之成分。本發明中，可於晶析開始時添加各成分使各成分成為上述比例。又，本發明之反應系也可以含有觸媒等其他成分。>Crystallization step> In the present invention, the cyclohexane tricarboxylic acid anhydride contains 0-100% by mass of monocarboxylic acid which is liquid at 20°C and 100-0% by mass of monocarboxylic acid which is liquid at 20°C. The crystallization of the solvent (except that the total of the monocarboxylic acid and the monocarboxylic anhydride does not exceed 100% by mass) is a step of crystallization. The crystallization system contains components from the mother liquor after the crystallization of cyclohexanetricarboxylic acid anhydride at the beginning of the crystallization, Including the addition of each component so that the composition of the crystallization system at the start of crystallization (hereinafter sometimes referred to as "initial state") becomes a compound represented by the following formula (1) in excess of 0.20 part by mass and 1.00 part by mass, Cyclohexane tricarboxylic acid anhydride is a step of 5.0 to 49.9 parts by mass and the solvent is a step of 50 to 95.0 parts by mass, and the aforementioned crystallization system is cooled to crystallize. Usually, the reaction liquid after the above acid anhydride step is directly cooled. With such a structure, the liquid content of wet crystals can be low. The crystallization system of the present invention contains the components derived from the mother liquor, the compound represented by formula (1), cyclohexanetricarboxylic anhydride, and the solvent in the initial state. However, part of the compound represented by formula (1), cyclohexanetricarboxylic anhydride, and solvent may also be components derived from the mother liquor. In the present invention, each component may be added at the start of crystallization so that each component becomes the above-mentioned ratio. In addition, the reaction system of the present invention may contain other components such as a catalyst.
>>式(1)表示之化合物>>
本發明中，晶析系存在式(1)表示之化合物。藉由存在前述化合物，推測會促進結晶化。再者，式(1)表示之化合物據推測會控制結構。結果據認為獲得之濕晶之含液率會降低。
式(1)
式(1)表示之化合物宜為4-甲基-1,2-環己烷二羧酸酐較佳。The compound represented by formula (1) is preferably 4-methyl-1,2-cyclohexanedicarboxylic anhydride.
>>環己烷三羧酸酐>> 環己烷三羧酸酐宜為環己烷-1,2,4-三羧酸-1,2-酐較佳。 該等環己烷三羧酸酐為順式體、反式體、混合物皆可。本發明宜至少含有順式體較佳。環己烷三羧酸酐中，順式體之比例為90質量%以上較佳，95質量%以上更佳，97質量%以上又更佳。就上限而言，順式體之比例為99.9質量%以下較佳。順式體比率較高時有產率提高的傾向，較理想。>>Cyclohexane Tricarboxylic Anhydride>> Cyclohexane tricarboxylic acid anhydride is preferably cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride. These cyclohexane tricarboxylic acid anhydrides can be in cis form, trans form, or mixture. The present invention preferably contains at least a cis-isomer. In the cyclohexanetricarboxylic anhydride, the ratio of the cis isomer is preferably 90% by mass or more, more preferably 95% by mass or more, and even more preferably 97% by mass or more. As for the upper limit, the ratio of the cis isomer is preferably 99.9% by mass or less. When the ratio of cis-body is higher, the yield tends to increase, which is ideal.
>>溶劑>> 溶劑包括於20℃為液體之一元羧酸0~100質量%及於20℃為液體之一元羧酸之酸酐100~0質量%。溶劑宜含有一元羧酸50~100質量%及於20℃為液體之一元羧酸之酸酐0~50質量%較佳，含有一元羧酸60~90質量%及於20℃為液體之一元羧酸之酸酐10~40質量%更佳。藉由以此方式併用一元羧酸及一元羧酸之酸酐，母液之再利用能夠更安定進行。 就於20℃為液體之一元羧酸而言，可列舉乙酸、丙酸，乙酸為較佳。 就於20℃為液體之一元羧酸之酸酐而言，宜為上述一元羧酸之酸酐(一元羧酸酐)為較佳。尤其一元羧酸與一元羧酸之酸酐組合時，一元羧酸之酸酐宜為併用之一元羧酸之酸酐較佳。 就於20℃為液體之一元羧酸之酸酐而言，可列舉乙酸酐、丙酸酐，乙酸酐為較佳。>>Solvent>> The solvent includes 0-100% by mass of liquid monocarboxylic acid at 20°C and 100-0% by mass of anhydride that is liquid monocarboxylic acid at 20°C. The solvent should preferably contain 50-100% by mass of monocarboxylic acid and 0-50% by mass of anhydride which is liquid monocarboxylic acid at 20°C, preferably 60~90% by mass of monocarboxylic acid and liquid monocarboxylic acid at 20°C The acid anhydride is preferably 10-40% by mass. By combining the monocarboxylic acid and the acid anhydride of the monocarboxylic acid in this way, the reuse of the mother liquor can be performed more stably. As for monocarboxylic acids that are liquid at 20°C, acetic acid and propionic acid can be cited, and acetic acid is preferred. As far as the anhydrides of monocarboxylic acids are liquid at 20°C, the anhydrides of the above-mentioned monocarboxylic acids (monocarboxylic anhydrides) are preferred. Especially when combining monocarboxylic acid and monocarboxylic acid anhydride, the monocarboxylic acid anhydride is preferably the anhydride of monocarboxylic acid in combination. As for anhydrides of monocarboxylic acids that are liquid at 20°C, acetic anhydride and propionic anhydride can be cited, and acetic anhydride is preferred.
本發明中，環己烷三羧酸酐進行晶析時，可含有亦可不含一元羧酸及一元羧酸酐以外之其他溶劑。含有其他溶劑時，可列舉沸點50℃以上之烴系溶劑、鹵化烴系溶劑、酯系溶劑、酮系溶劑、醚系溶劑、脂肪酸系溶劑。含有其他溶劑時，其含量為溶劑之1~100質量%較佳。又，本發明中，也可採取實質不含一元羧酸及一元羧酸酐以外之其他溶劑之構成。實質不含係指其他溶劑未達溶劑之1質量%，0.1質量%以下較佳，0.05質量%以下更佳。 本發明中，在獲得環己烷三羧酸酐之步驟使用之溶劑與晶析步驟使用之溶劑之90質量%以上宜為共通較佳，95質量%以上共通更佳，99質量%以上共通又更佳。藉由為如此的構成，生產效率能更好。In the present invention, when cyclohexane tricarboxylic acid anhydride undergoes crystallization, it may or may not contain other solvents other than monocarboxylic acid and monocarboxylic anhydride. When other solvents are contained, hydrocarbon-based solvents, halogenated hydrocarbon-based solvents, ester-based solvents, ketone-based solvents, ether-based solvents, and fatty acid-based solvents having a boiling point of 50°C or higher can be cited. When other solvents are contained, the content is preferably 1-100% by mass of the solvent. Furthermore, in the present invention, it is also possible to adopt a configuration that does not substantially contain other solvents other than monocarboxylic acid and monocarboxylic anhydride. Substantially free means that other solvents do not reach 1% by mass of the solvent, preferably 0.1% by mass or less, and more preferably 0.05% by mass or less. In the present invention, 90% by mass or more of the solvent used in the step of obtaining cyclohexanetricarboxylic acid anhydride and the solvent used in the crystallization step are preferably common, more preferably 95% by mass or more, and more preferably 99% by mass or more. good. With such a structure, the production efficiency can be better.
>>其他成分>> 本發明之製造方法中，可於晶析系使用式(1)表示之化合物、環己烷三羧酸酐、溶劑以外之成分。具體而言可列舉環己烷三羧酸、二羧酸、二羧酸酐等。>>Other ingredients>> In the production method of the present invention, components other than the compound represented by formula (1), cyclohexanetricarboxylic anhydride, and solvent can be used in the crystallization system. Specifically, cyclohexane tricarboxylic acid, dicarboxylic acid, dicarboxylic anhydride, etc. can be mentioned.
>>式(1)表示之化合物、環己烷三羧酸酐、溶劑之比率>> 本發明中，初始狀態(晶析前之狀態)在晶析系中含有的式(1)表示之化合物之量為超過0.20質量%且1.00質量%以下較佳。初始狀態(晶析前之狀態)在晶析系中含有的式(1)表示之化合物之量較佳為0.25質量%以上，更佳為0.30質量%以上，更佳為0.34質量%以上，較佳為0.80質量%以下，更佳為0.60質量%以下。又，本發明中，初始狀態(晶析前之狀態)除了晶析系中含有的溶劑以外的成分中之式(1)表示之化合物之量為0.87質量%以上較佳，0.90質量%以上更佳。上限值，例如：3.0質量%以下較佳，2.5質量%以下更佳，2.0質量%以下又更佳。上式(1)表示之化合物之量，係指也包括來自母液之成分、來自環己烷三羧酸中含有的雜質之成分等的合計量。又，晶析系也可新加入式(1)表示之化合物。本發明中，在晶析前之酸酐化步驟時宜使用母液較佳，若採用如此的形態，即使未新添加式(1)表示之化合物，晶析系中含有的式(1)表示之化合物之量仍可為0.20~1.00質量%。>>The ratio of compound represented by formula (1), cyclohexanetricarboxylic acid anhydride and solvent >> In the present invention, the amount of the compound represented by formula (1) contained in the crystallization system in the initial state (the state before crystallization) is more than 0.20% by mass and preferably 1.00% by mass or less. The amount of the compound represented by formula (1) contained in the crystallization system in the initial state (the state before crystallization) is preferably 0.25% by mass or more, more preferably 0.30% by mass or more, and more preferably 0.34% by mass or more. It is preferably 0.80% by mass or less, and more preferably 0.60% by mass or less. In the present invention, the amount of the compound represented by formula (1) in the components other than the solvent contained in the crystallization system in the initial state (the state before crystallization) is preferably 0.87 mass% or more, more preferably 0.90 mass% or more good. The upper limit, for example, is preferably 3.0% by mass or less, more preferably 2.5% by mass or less, and even more preferably 2.0% by mass or less. The amount of the compound represented by the above formula (1) refers to the total amount including components derived from mother liquor, components derived from impurities contained in cyclohexanetricarboxylic acid, and the like. Moreover, the compound represented by formula (1) may be newly added to the crystallization system. In the present invention, it is better to use mother liquor in the acid anhydride step before crystallization. If such a form is adopted, even if the compound represented by formula (1) is not newly added, one of the compounds represented by formula (1) contained in the crystallization system The amount can still be 0.20 to 1.00 mass%.
本發明中，初始狀態在晶析系中含有的環己烷三羧酸酐之量，宜相對於式(1)表示之化合物超過0.20質量份且1.00質量份以下為10質量份以上較佳，15質量份以上更佳，20質量份以上又更佳，又，50質量份以下較佳，40質量份以下更佳，30質量份以下又更佳。藉由為如此的範圍，可有效防止由於系內之環己烷三羧酸酐量過低導致之釜效率下降，且可有效防止由於環己烷三羧酸酐量過高導致之結晶性狀之變化所伴隨之含液率之惡化。 本發明中，初始狀態在晶析系中含有的溶劑之量相對於式(1)表示之化合物超過0.20質量份且1.00質量份，宜為40質量份以上較佳，50質量份以上更佳，60質量份以上又更佳，又，90質量份以下較佳，85質量份以下更佳，80質量份以下又更佳。藉由為如此的範圍，濕晶之含液率會更低。前述溶劑，如上所述，係指包括於20℃為液體之一元羧酸0~100質量%及於20℃為液體之一元羧酸之酸酐100~0質量%之溶劑全量。In the present invention, the amount of cyclohexanetricarboxylic acid anhydride contained in the crystallization system in the initial state is preferably more than 0.20 parts by mass and 1.00 parts by mass or less and 10 parts by mass or more relative to the compound represented by formula (1). More preferably, it is more than 20 parts by mass, more preferably more than 20 parts by mass, more preferably less than 50 parts by mass, more preferably less than 40 parts by mass, and more preferably less than 30 parts by mass. By being in such a range, it is possible to effectively prevent the decrease in pot efficiency due to the too low amount of cyclohexanetricarboxylic acid anhydride in the system, and to effectively prevent the change in crystal properties caused by the excessive amount of cyclohexanetricarboxylic acid anhydride. Concomitant deterioration of liquid content. In the present invention, the amount of the solvent contained in the crystallization system in the initial state exceeds 0.20 parts by mass and 1.00 parts by mass relative to the compound represented by formula (1), preferably 40 parts by mass or more, more preferably 50 parts by mass or more, It is more preferably 60 parts by mass or more, more preferably 90 parts by mass or less, more preferably 85 parts by mass or less, and more preferably 80 parts by mass or less. With such a range, the liquid content of the wet crystal will be lower. The aforementioned solvent, as mentioned above, refers to the total amount of the solvent including 0-100% by mass of the liquid monocarboxylic acid at 20°C and 100-0% by mass of the anhydride of the liquid monocarboxylic acid at 20°C.
又，初始狀態之晶析系中，式(1)表示之化合物、環己烷三羧酸酐及溶劑之合計為85質量%以上較佳，90質量%以上更佳，95質量%以上又更佳，98質量%以上更佳，99質量%以上又更佳。 又，本發明中，可於初始狀態之晶析系中存在環己烷三羧酸。In addition, in the initial crystallization system, the total of the compound represented by formula (1), cyclohexanetricarboxylic acid anhydride, and solvent is preferably 85% by mass or more, more preferably 90% by mass or more, and more preferably 95% by mass or more , 98% by mass or more is more preferable, and 99% by mass or more is even more preferable. Furthermore, in the present invention, cyclohexanetricarboxylic acid may be present in the crystallization system in the initial state.
針對式(1)表示之化合物、環己烷三羧酸酐、溶劑、其他成分，可以各僅使用1種，也可使用2種以上。使用2種以上時，合計量成為上述範圍較佳。Regarding the compound represented by formula (1), cyclohexanetricarboxylic anhydride, solvent, and other components, only one type may be used each, or two or more types may be used. When two or more types are used, the total amount is preferably in the above range.
>>晶析之反應條件>> 晶析時之溫度不特別限定，上述酸酐化步驟之結束時之溫度為80~150℃較佳，90~140℃更佳，95~130℃尤佳。又，就冷卻溫度(晶析終點溫度)而言，無特殊限制，但考慮產率改善及操作效率之觀點，-10~50℃較理想，0~40℃更佳，10~30℃尤佳。針對冷卻速度，考慮純度改善及時間效率之觀點，5~30℃/小時較理想，7~25℃/小時更佳，7~20℃/小時又更理想，10~20℃/小時尤佳。 再者，宜於晶析終點溫度實施熟成較佳。熟成時間例如：10分鐘~2小時較佳。 晶析時之溫度(酸酐化步驟之結束時之溫度)與熟成之溫度之差距宜為50℃以上較佳，60℃以上較佳，70℃以上更佳。前述溫度之差距之上限無特殊限定，可設為例如：90℃以下。 晶析宜邊攪拌邊進行較佳。>>Reaction conditions for crystallization >> The temperature during the crystallization is not particularly limited, and the temperature at the end of the acid anhydride step is preferably 80-150°C, more preferably 90-140°C, and particularly preferably 95-130°C. In addition, there is no special limitation on the cooling temperature (the end temperature of crystallization), but considering the improvement of yield and operating efficiency, -10~50°C is ideal, 0~40°C is more preferred, and 10~30°C is particularly preferred. . Regarding the cooling rate, considering purity improvement and time efficiency, 5~30°C/hour is ideal, 7~25°C/hour is better, 7~20°C/hour is even more ideal, and 10~20°C/hour is especially preferred. Furthermore, it is better to perform maturation at the end temperature of crystallization. For example, the maturation time is 10 minutes to 2 hours. The difference between the temperature during crystallization (the temperature at the end of the acid anhydride step) and the maturation temperature is preferably 50°C or more, preferably 60°C or more, and more preferably 70°C or more. The upper limit of the aforementioned temperature difference is not particularly limited, and can be set, for example, below 90°C. It is better to perform crystallization while stirring.
>固液分離步驟>
本發明之製造方法，宜於晶析後將母液與環己烷三羧酸酐之結晶予以分離較佳。
例如可將晶析後之反應液利用過濾分離為固體成分結晶(濕晶)、及液體成分(母液)。過濾溫度無特殊限制，-15~50℃較理想，-10~40℃更佳，0~35℃尤佳。
固液分離步驟，例如可使用離心分離機於室溫(例如：20~40℃)，以離心加速度450G旋轉直到濾液消失為止，以進行分離。又，漿液供給時可以降低旋轉速度。之後可實施固體(濕結晶)之洗淨。
分離後的母液可在本發明之酸酐化步驟中作為摻合之母液而理想地使用。亦即，本發明在初始狀態之晶析系中含有的來自母液之成分，係來自於將環己烷三羧酸酐之結晶分離之後之母液。如此，藉由將母液再利用，能夠使獲得之濕晶之含液率低，且能節省原料。
母液可以直接將全量再利用，也可排除一部分母液後再利用。藉由將母液之一部分排出，能夠調整系內之雜質濃度、式(1)表示之化合物之濃度。
針對母液，宜將其60質量%以上再利用較佳，65質量%以上再利用更佳，70質量%以上再利用又更佳。前述再利用量之上限可為100質量%，但即使為例如90質量%以下，進而80質量%以下仍為有充分意義的態樣。
本發明中，宜邊將母液再利用邊投入新的原料，而連續地進行環己烷三羧酸的酸酐化步驟及晶析步驟較佳。亦即宜包括1次或2次以上的下列步驟較佳：在分離了環己烷三羧酸酐之結晶後之母液中重新摻合環己烷三羧酸及溶劑等並調整成上述比例，並於酸酐化步驟後使其晶析。本發明中，宜重複前述步驟1~100次較佳。藉由重複多數次的再利用步驟，晶析系中之式(1)表示之化合物之量安定且能使濕晶之含液率更安定地為低。>Solid-liquid separation step>
In the production method of the present invention, it is better to separate the mother liquor and the crystallization of cyclohexanetricarboxylic acid anhydride after crystallization.
For example, the reaction liquid after crystallization can be separated into a solid component crystal (wet crystal) and a liquid component (mother liquor) by filtration. There is no special restriction on the filtration temperature, -15~50℃ is ideal, -10~40℃ is better, and 0~35℃ is especially preferred.
In the solid-liquid separation step, for example, a centrifugal separator can be used at room temperature (for example: 20-40° C.) and rotated at a centrifugal acceleration of 450G until the filtrate disappears for separation. In addition, the rotation speed can be reduced during slurry supply. The solid (wet crystal) can be washed afterwards.
The separated mother liquor can be ideally used as a blended mother liquor in the acid anhydride step of the present invention. That is, the components derived from the mother liquor contained in the crystallization system in the initial state of the present invention are derived from the mother liquor after the crystals of cyclohexanetricarboxylic anhydride are separated. In this way, by reusing the mother liquor, the liquid content of the obtained wet crystals can be low, and raw materials can be saved.
The mother liquor can be reused in full, or it can be reused after excluding a part of the mother liquor. By discharging part of the mother liquor, the concentration of impurities in the system and the concentration of the compound represented by formula (1) can be adjusted.
Regarding the mother liquor, it is better to reuse more than 60% by mass, more preferably more than 65% by mass, and more preferably more than 70% by mass. The upper limit of the aforementioned reuse amount may be 100% by mass, but even if it is, for example, 90% by mass or less, 80% by mass or less is still a sufficiently meaningful aspect.
In the present invention, it is preferable to input new raw materials while reusing the mother liquor, and it is preferable to continuously perform the acid anhydride step and the crystallization step of cyclohexanetricarboxylic acid. That is to say, it is better to include the following steps once or more than two times: in the mother liquor after the crystallization of cyclohexane tricarboxylic acid anhydride is separated, cyclohexane tricarboxylic acid and solvent are re-blended and adjusted to the above ratio, and After the acid anhydride step, crystallize it. In the present invention, it is better to repeat the
>乾燥> 本發明之製造方法宜更包括將已分離之環己烷三羧酸酐之結晶予以乾燥之步驟較佳。藉由進行乾燥，能夠完全去除溶劑。 乾燥溫度宜為50℃以上較佳，60℃以上更佳。又，乾燥溫度之上限為140℃以下較佳，135℃以下更佳，130℃又更佳。 乾燥時間取決於乾燥溫度、結晶之尺寸，宜為0.5~15小時更佳。 也可於減壓下實施乾燥。再者，可於乾燥時供給氮氣等。 乾燥機無特殊限制，可使用靜置式(棚架式)乾燥機、旋轉式乾燥機等，但考慮乾燥效率高、乾燥時間可為短的觀點，使用旋轉式乾燥機較佳。旋轉式乾燥機可列舉錐形乾燥機、蒸發器。 乾燥例如可於5~100mmHg之壓力下加熱到60~100℃而使其乾燥。>drying> The production method of the present invention preferably further includes the step of drying the separated crystals of cyclohexanetricarboxylic acid anhydride. By drying, the solvent can be completely removed. The drying temperature is preferably 50°C or higher, more preferably 60°C or higher. In addition, the upper limit of the drying temperature is preferably 140°C or less, more preferably 135°C or less, and even more preferably 130°C. The drying time depends on the drying temperature and the size of the crystals, preferably 0.5 to 15 hours. It can also be dried under reduced pressure. Furthermore, nitrogen or the like can be supplied during drying. The dryer is not particularly limited, and static (shelf-type) dryers, rotary dryers, etc. can be used. However, in consideration of the high drying efficiency and the short drying time, it is preferable to use a rotary dryer. Examples of the rotary dryer include a cone dryer and an evaporator. For drying, for example, it can be dried by heating to 60-100°C under a pressure of 5-100 mmHg.
>產率> 本發明之結晶之製造方法中，產率可為60mol%以上，也可為68mol%以上。產率之上限宜為100mol%，但即使為80mol%以下亦為充分實用的水平。>Yield> In the method for producing crystals of the present invention, the yield may be 60 mol% or more, or 68 mol% or more. The upper limit of the yield is preferably 100 mol%, but even 80 mol% or less is a sufficiently practical level.
>結晶> 本發明之結晶，係以環己烷三羧酸酐作為主成分且含有0.025~0.1質量%之式(1)表示之化合物之結晶。 如此的結晶係藉由本發明之結晶之製造方法獲得。又，當然本發明之結晶，即使是以本發明之結晶之製造方法以外之方法獲得之結晶也包括在本發明之範圍中。 本發明之結晶係以環己烷三羧酸酐作為主成分。在此，主成分係指例如：環己烷三羧酸酐之比例為80.0質量%以上，90.0質量%以上較佳，95.0質量%以上更佳，97質量%以上又更佳，98.0質量%以上更理想，98.5質量%以上又更好。前述環己烷三羧酸酐為順式體、反式體、混合物皆可。本發明中可至少含有順式體，於此情形，環己烷三羧酸酐中之順式體之比例可為例如：90.00質量%以上、95.00質量%以上、98.00質量%以上、99.00質量%以上。就上限而言，順式體之比例可為100質量%以下，也可為99.99質量%以下。亦即，也可列舉少量(例如：超過0質量%且為0.05質量%以下之量)含有順式體以外之環己烷三羧酸酐之態樣。結晶可僅含有1種環己烷三羧酸酐，也可含2種以上。含2種以上時，合計量成為上述範圍較佳。 本發明之結晶宜含有0.030質量%以上之式(1)表示之化合物較佳，含有0.035質量%以上更佳，也可含有0.045質量%以上。又，本發明之結晶，宜含有0.1000質量%以下之式(1)表示之化合物較佳，含有0.095質量%以下更佳，含有0.090質量%以下又更佳。本發明之結晶可以僅含有1種式(1)表示之化合物，也可含有2種以上。含有2種以上時，合計量成為上述範圍較佳。 本發明之結晶中，於20℃之含液率為8.5質量%以下較佳，8.3質量%以下更佳，8.0質量%以下又更佳，7.5質量%以下更理想，7.0質量%以下又更佳。又，含液率之下限宜為0質量%，但即使是1.0質量%以上亦為實用的水平。含液率係依後述實施例記載的方法測定。本發明之結晶，尤其係本發明之製造方法獲得者，宜為從反應液分離之環己烷三羧酸酐之結晶且後述乾燥前之結晶(濕結晶)之含液率符合上述範圍較佳。濕晶通常其表面會存在液體，但此液係通常係晶析後之母液。 式(1)表示之化合物之結構之理想範圍，和在上述結晶之製造方法所述事項為同義，理想範圍也是同樣。 本發明之結晶之尺寸，按體積基準平均粒徑計為20μm以上較佳，按體積基準平均粒徑計為50μm以上更佳。若為如此的尺寸，則能夠更有效地降低結晶之含液率。針對上限值無特殊限定，例如為500μm以下係實際。>Crystal> The crystal of the present invention is a crystal containing cyclohexanetricarboxylic anhydride as the main component and containing 0.025 to 0.1% by mass of the compound represented by formula (1). Such crystals are obtained by the method of producing crystals of the present invention. Also, of course, the crystal of the present invention, even a crystal obtained by a method other than the method for producing the crystal of the present invention, is included in the scope of the present invention. The crystal system of the present invention uses cyclohexane tricarboxylic anhydride as the main component. Here, the main component refers to, for example, the ratio of cyclohexanetricarboxylic acid anhydride is 80.0% by mass or more, preferably 90.0% by mass or more, more preferably 95.0% by mass or more, more preferably 97% by mass or more, more preferably 98.0% by mass or more Ideally, 98.5 mass% or more is even better. The aforementioned cyclohexane tricarboxylic acid anhydride may be a cis form, a trans form, or a mixture. The present invention may contain at least the cis isomer. In this case, the ratio of the cis isomer in the cyclohexanetricarboxylic acid anhydride can be, for example, 90.00 mass% or more, 95.00 mass% or more, 98.00 mass% or more, 99.00 mass% or more . As far as the upper limit is concerned, the ratio of the cis isomer may be 100% by mass or less, or 99.99% by mass or less. That is, a small amount (for example, an amount exceeding 0% by mass and less than 0.05% by mass) containing cyclohexanetricarboxylic anhydride other than the cis isomer may also be mentioned. The crystal may contain only one type of cyclohexanetricarboxylic anhydride, or two or more types. When two or more types are contained, the total amount is preferably in the above range. The crystal of the present invention preferably contains 0.030% by mass or more of the compound represented by formula (1), preferably 0.035% by mass or more, and may also contain 0.045% by mass or more. In addition, the crystal of the present invention preferably contains 0.1000 mass% or less of the compound represented by formula (1), more preferably 0.095 mass% or less, and even more preferably 0.090 mass% or less. The crystal of the present invention may contain only one compound represented by the formula (1), or may contain two or more kinds. When two or more types are contained, the total amount is preferably in the above range. In the crystal of the present invention, the liquid content at 20°C is preferably 8.5% by mass or less, more preferably 8.3% by mass or less, more preferably 8.0% by mass or less, more preferably 7.5% by mass or less, and more preferably 7.0% by mass or less . In addition, the lower limit of the liquid content is preferably 0% by mass, but even 1.0% by mass or more is a practical level. The liquid content was measured in accordance with the method described in the following Examples. The crystals of the present invention, especially those obtained by the production method of the present invention, are preferably the crystals of cyclohexanetricarboxylic anhydride separated from the reaction liquid, and the liquid content of the crystals before drying (wet crystals) described below falls within the above range. The wet crystal usually has liquid on its surface, but this liquid is usually the mother liquid after crystallization. The ideal range of the structure of the compound represented by the formula (1) is synonymous with the matters described in the above-mentioned crystal manufacturing method, and the ideal range is also the same. The size of the crystals of the present invention is preferably 20 μm or more in terms of volume-based average particle size, and more preferably 50 μm or more in terms of volume-based average particle size. If it is such a size, the liquid content of the crystal can be reduced more effectively. There is no particular limitation on the upper limit, and for example, 500 μm or less is practical.
>用途> 本發明之環己烷三羧酸酐之結晶可以作為環氧樹脂等熱硬化性樹脂之硬化劑使用。具體而言，可以參酌日本特開2013-112643號公報之段落0024~0029之記載，該等內容納入在本說明書。 又，本發明之環己烷三羧酸酐之結晶可理想地作為阻焊材料之酸改性劑使用。具體而言，可理想地作為對於環氧丙烯酸酯等阻焊材料賦予酸基之改性劑。阻焊材料只要是於印刷配線板、半導體封裝體用電路基板通常使用之阻焊材料即可，並不限定。舉例而言，可以列舉由丙烯酸酯-環氧樹脂等構成之熱硬化性・光硬化性光阻材料等。阻焊材料之詳情可以參酌日本特開2014-052599號公報之記載，該等內容納入於本說明書。 又，本發明之環己烷三羧酸酐之結晶，除了上述以外，在塗料、黏接劑、成形品、半導體之密封劑用樹脂、聚醯亞胺樹脂、聚醯胺醯亞胺樹脂、聚醯胺樹脂、聚酯樹脂、醇酸樹脂等原料、改質劑或改性劑、塑化劑、潤滑油原料、醫農藥中間體、塗料用樹脂原料、色劑用樹脂等用途也有用。 [實施例]>Use> The crystal of cyclohexanetricarboxylic acid anhydride of the present invention can be used as a curing agent for thermosetting resins such as epoxy resins. Specifically, you can refer to the description of paragraphs 0024 to 0029 of JP 2013-112643 A, and these contents are incorporated in this specification. In addition, the crystal of cyclohexanetricarboxylic anhydride of the present invention can be ideally used as an acid modifier for solder resist materials. Specifically, it is ideal as a modifier that imparts acid groups to solder resist materials such as epoxy acrylate. The solder resist material is not limited as long as it is a solder resist material generally used for printed wiring boards and circuit boards for semiconductor packages. For example, a thermosetting/photocuring photoresist composed of acrylate-epoxy and the like can be cited. For details of solder mask materials, please refer to the records in JP 2014-052599, which are included in this manual. In addition, the crystals of cyclohexanetricarboxylic acid anhydride of the present invention are used in paints, adhesives, molded products, semiconductor sealing agent resins, polyimide resins, polyimide imide resins, and polyimide resins, in addition to the above. Amide resins, polyester resins, alkyd resins and other raw materials, modifiers or modifiers, plasticizers, lubricating oil raw materials, medical and agricultural intermediates, resin raw materials for paints, resins for colorants, and the like are also useful. [Example]
以下舉實施例對於本發明更具體說明。以下之實施例所示之材料、使用量、比例、處理內容、處理程序等，只要不脫離本發明之要旨，皆可適當改變。因此本發明之範圍不限於以下所示之具體例。 本實施例中，MeHHPA代表4-甲基-1,2-環己烷二羧酸酐，H-TMA代表環己烷三羧酸，H-TMAn代表環己烷三羧酸酐，H-TMAn(cis體)代表環己烷三羧酸酐之順式體，H-TMAn(其他)代表順式體以外之環己烷三羧酸酐。The following examples illustrate the present invention in more detail. The materials, usage amount, ratio, processing content, processing procedure, etc. shown in the following embodiments can be appropriately changed as long as they do not depart from the gist of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. In this example, MeHHPA represents 4-methyl-1,2-cyclohexane dicarboxylic anhydride, H-TMA represents cyclohexane tricarboxylic acid, H-TMAn represents cyclohexane tricarboxylic anhydride, H-TMAn(cis (Form) represents the cis form of cyclohexane tricarboxylic acid anhydride, and H-TMAn (others) represents cyclohexane tricarboxylic anhydride other than the cis form.
>比較例1(母液之製造)> >>環己烷三羧酸酐之製造(酸酐化步驟)>> 對於環己烷三羧酸(三菱瓦斯化學公司製、製品名：H-TMA)摻合乙酸(JNC公司製、99%工業用乙酸)、乙酸酐(富士軟片和光純藥公司製、型號011-00271)，進行加熱酸酐化，獲得環己烷三羧酸酐。 具體而言，於4L的不銹鋼製晶析槽中裝入H-TMA(255.7g)、乙酸酐(170.5g)及乙酸(852.4g)，邊攪拌邊加熱直到液溫成為100℃。於液溫成為100℃之時點(成為穩定狀態之時點)作為反應開始，於100℃繼續反應1小時。以下稱獲得之環己烷三羧酸酐(包括H-TMAn(cis體)及H-TMAn(其他)兩者)為H-TMAn-S。產率為65.67%、脫水率為99.65質量%。>Comparative example 1 (manufacturing of mother liquor)> >>Production of cyclohexane tricarboxylic acid anhydride (acid anhydride step) >> For cyclohexane tricarboxylic acid (manufactured by Mitsubishi Gas Chemical Company, product name: H-TMA), acetic acid (manufactured by JNC, 99% industrial acetic acid) and acetic anhydride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., model 011- 00271), heating and acid anhydride to obtain cyclohexane tricarboxylic acid anhydride. Specifically, H-TMA (255.7 g), acetic anhydride (170.5 g), and acetic acid (852.4 g) were charged in a 4 L stainless steel crystallization tank, and heated with stirring until the liquid temperature became 100°C. The reaction was started when the liquid temperature reached 100°C (the time when it became a stable state), and the reaction was continued at 100°C for 1 hour. Hereinafter, the obtained cyclohexane tricarboxylic acid anhydride (including both H-TMAn (cis body) and H-TMAn (other)) is referred to as H-TMAn-S. The yield was 65.67%, and the dehydration rate was 99.65% by mass.
>>晶析步驟及固液分離步驟>> 將上述反應液之溫度以10℃/小時之速度從100℃下降，於到達20℃後進行1小時熟成，使其晶析。 將上述經晶析之反應液使用離心分離機，以離心加速度450G旋轉直到不再出現濾液，分離為固體(濕晶)及液體。 獲得之固體認定為環己烷-1,2,4-三羧酸-1,2-酐之結晶(濕晶)。結晶之產率為65.67mol%。 針對獲得之濕結晶，如後述，測定含液率。已分離之液(母液)，用在後述實施例。 將已測定含液率之濕晶以(130℃×12小時)之條件乾燥，獲得乾晶。>>Crystallization step and solid-liquid separation step>> The temperature of the reaction liquid was lowered from 100°C at a rate of 10°C/hour, and after reaching 20°C, it was aged for 1 hour to crystallize. The above-mentioned crystallized reaction liquid is used in a centrifugal separator and rotated at a centrifugal acceleration of 450G until the filtrate no longer appears, and is separated into solid (wet crystal) and liquid. The obtained solid is regarded as the crystal (wet crystal) of cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride. The yield of crystals was 65.67 mol%. Regarding the obtained wet crystals, the liquid content was measured as described later. The separated liquid (mother liquor) was used in the following Examples. The wet crystals whose liquid content has been measured are dried under the condition of (130°C×12 hours) to obtain dry crystals.
利用後述GC(氣體層析)分析及LC(液體層析)來測定上述反應液亦即晶析系之初始之各成分之量，結果如表1。具體而言，分析時，依後述固體液體分離的方法來分離為濕晶及濕晶以外之成分(液體)。針對濕晶及液體，分別以下列方式進行分析。之後將濕晶與液體中含有的各成分之量相加，並算出各成分之量。 在分析濕晶及液體時，如圖2，利用GC分析來測定試樣中之H-TMA及H-TMAn之合計量、及MeHHPA。再者，利用LC分析測定H-TMA及H-TMAn中之H-TMA之量，算出H-TMAn-S(酸酐之合計量)之量。 又，針對乾晶，也利用後述GC(氣體層析)分析及LC(液體層析)測定，結果如表1。The following GC (gas chromatography) analysis and LC (liquid chromatography) were used to determine the amount of the initial components of the reaction solution, that is, the crystallization system. The results are shown in Table 1. Specifically, at the time of analysis, it is separated into wet crystals and components (liquid) other than wet crystals according to the solid-liquid separation method described later. For wet crystals and liquids, the following methods are used for analysis. After that, the wet crystal and the amount of each component contained in the liquid are added, and the amount of each component is calculated. When analyzing wet crystals and liquids, as shown in Figure 2, GC analysis is used to determine the total amount of H-TMA and H-TMAn in the sample, and MeHHPA. Furthermore, the amount of H-TMA in H-TMA and H-TMAn was measured by LC analysis, and the amount of H-TMAn-S (the total amount of acid anhydride) was calculated. In addition, for the dry crystals, GC (gas chromatography) analysis and LC (liquid chromatography) measurement described later were also used. The results are shown in Table 1.
>>GC分析方法・・試樣中之H-TMA及H-TMAn之合計純度之定量>> 環己烷三羧酸(H-TMA(cis體、其他)、H-TMAn-S)之合計量之純度(質量%)，係利用氣體層析(GC)來分析經下列之條件進行前處理之試樣，並依下式算出。 GC純度(質量%)＝[(H-TMA之峰部面積)÷(全部峰部(不含溶劑)之面積合計)]×100 上述面積%記載為質量%。 >>>氣體層析用之前處理條件>>> (酯化條件(磷酸三甲酯法)) 精秤下列實施例及比較例獲得之試樣(反應液中含有的濕晶、反應液中含有的濕晶以外之成分、或乾晶)0.1g，對其加入沸騰石、三乙基氯化銨(和光1級)3g、磷酸三甲酯(KISHIDA化學1級)10mL，之後於加熱組(180℃)內加熱90分鐘並酯化。 反應後冷卻到室溫，於試管中加入氯仿15mL使其溶解，將全量移到分液漏斗，加入純水100mL。將分液漏斗振盪10分鐘後，靜置約5分鐘，使液體分離為二層。以滴管將上層(水相)抽吸排出，再加入純水100mL。振盪分液漏斗10分鐘後，靜置約5分鐘，將液體分離為二層。通過濾紙(5B)收集下層的氯仿相，供GC分析。>>GC analysis method・・Quantification of the total purity of H-TMA and H-TMAn in the sample>> The total purity (mass%) of cyclohexane tricarboxylic acid (H-TMA (cis body, other), H-TMAn-S) is analyzed by gas chromatography (GC) and pre-treated under the following conditions The sample is calculated according to the following formula. GC purity (mass%)=[(H-TMA peak area)÷(total area of all peaks (without solvent))]×100 The above area% is described as mass %. >>>Pretreatment conditions for gas chromatography >>> (Esterification conditions (trimethyl phosphate method)) Finely weigh 0.1 g of the sample (wet crystal contained in the reaction solution, components other than the wet crystal contained in the reaction solution, or dry crystal) obtained in the following examples and comparative examples, and add zeolite and triethyl chloride to it Ammonium (Wako 1st grade) 3g, trimethyl phosphate (KISHIDA Chemical 1st grade) 10mL, and then heated in a heating group (180°C) for 90 minutes and esterified. After the reaction, it was cooled to room temperature, 15 mL of chloroform was added to the test tube to dissolve, the whole amount was transferred to a separatory funnel, and 100 mL of pure water was added. After shaking the separatory funnel for 10 minutes, let it stand for about 5 minutes to separate the liquid into two layers. Use a dropper to suck out the upper layer (water phase) and add 100 mL of pure water. After shaking the separatory funnel for 10 minutes, let it stand for about 5 minutes to separate the liquid into two layers. The lower chloroform phase was collected through filter paper (5B) for GC analysis.
(酯化條件(BF3 ・MeOH法)・・H-TMA之cis/trans比率之定量) 收集0.60g之含有1,2,4-環己烷三羧酸之原料水溶液於試管中，加入三氟化硼甲醇溶劑(東京化成工業公司製)10mL，以150℃的加熱組加熱6分鐘，進行酯化處理。反應結束後加入氯仿3mL，按照水、0.5N碳酸鈉水溶液、水的順序進行分液處理，並將獲得之氯仿溶液供氣體層析分析。針對(cis-H-TMA+cis-H-TMAn)：(trans-H-TMA+cis-H-TMAn)，以面積百分率(單面法)計算。又，GC分析中，H-TMA與H-TMAn係於同一峰部中檢測到。故針對試樣中之H-TMA與H-TMAn之選擇性(質量比)，依後述LC分析來定量。(Esterification conditions (BF 3 ·MeOH method)··Quantification of cis/trans ratio of H-TMA) Collect 0.60g of raw material aqueous solution containing 1,2,4-cyclohexanetricarboxylic acid in a test tube, and add three 10 mL of boron fluoride methanol solvent (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was heated with a heating unit at 150°C for 6 minutes to perform esterification treatment. After the completion of the reaction, 3 mL of chloroform was added, liquid separation was performed in the order of water, 0.5N sodium carbonate aqueous solution, and water, and the obtained chloroform solution was subjected to gas chromatography analysis. For (cis-H-TMA+cis-H-TMAn): (trans-H-TMA+cis-H-TMAn), calculated as area percentage (single-sided method). In addition, in the GC analysis, H-TMA and H-TMAn were detected in the same peak. Therefore, the selectivity (mass ratio) of H-TMA and H-TMAn in the sample is quantified according to the LC analysis described later.
>>>氣體層析分析條件>>> 氣體層析分析條件如下。 使用設備：氣體層析 Agilent HP-6890 管柱：DB-1 (長度30m、內徑0.53mm、膜厚1.5μm) 檢測器：FID(H2 30mL/分、Air 300mL/分) 載流氣體：He(定速流動；平均線速38cm/秒) 分流比：11 注入口溫度：300℃ 檢測器溫度：290℃ 注入量：1.0μL OVEN(烘箱)溫度：於160℃保持20分鐘後，以10℃/分的速度升溫，到達280℃後保持15分鐘。>>>Gas chromatography analysis conditions >>> The gas chromatography analysis conditions are as follows. Equipment used: gas chromatography Agilent HP-6890 column: DB-1 (length 30m, inner diameter 0.53mm, film thickness 1.5μm) Detector: FID (H 2 30mL/min, Air 300mL/min) Carrier gas: He (constant velocity flow; average linear velocity 38cm/sec) Split ratio: 11 Injection inlet temperature: 300℃ Detector temperature: 290℃ Injection volume: 1.0μL OVEN (oven) temperature: After keeping at 160℃ for 20 minutes, 10 The temperature is increased at a rate of °C/min, and it is maintained for 15 minutes after reaching 280 °C.
>>脫水率之測定>>
針對環己烷三羧酸(H-TMA)之脫水率，係將試樣以液體層析(LC)進行分析，並將原料之1,2,4-環己烷三羧酸定量，再依如下式算出脫水率(質量%)。
脫水率(質量%)＝100-試樣中之環己烷三羧酸(H-TMA)之量(質量%)>>Determination of dehydration rate>>
Regarding the dehydration rate of cyclohexanetricarboxylic acid (H-TMA), the sample was analyzed by liquid chromatography (LC), and the
(液體層析用之前處理條件)
精秤試樣2g，加入脫水甲醇100mL並加熱，使其回流1小時並進行甲酯化反應，製備成液體層析用試樣。
又，於此前處理，試樣中之反應原料1,2,4-環己烷三羧酸未被酯化。(Pretreatment conditions for liquid chromatography)
2 g of the sample was finely weighed, 100 mL of dehydrated methanol was added, heated, refluxed for 1 hour, and methyl esterification reaction was performed to prepare a sample for liquid chromatography.
In addition, in the previous treatment, the
(液體層析分析條件) 液體層析分析條件如下。 液體層析分析裝置：LC-6AD(送液單元)、CTO-10A(恒溫槽)、SCL-10A(UV)、SPD-10AV(UV-VIS檢測器)、SPD-M20A(PDA檢測器) 管柱：Shodex RSpak DE-413L 檢測器：UV(210nm) 溶離液組成：A液＝乙腈、B液＝0.5%磷酸水溶液 模式：二元梯度 流速：1.0mL/分 恒溫槽溫度：35℃ 溶離液之條件如下。於分析時間0~15分鐘，設A液：B液＝10：90(體積比)，於15~20分鐘，施以A液：B液＝10：90(體積比)~50：50(體積比)的梯度。再者，於分析時間20~25分鐘，施以A液：B液＝50：50(體積比)~80：20(體積比)之梯度。維持A液：B液＝80：20(體積比)直到40分鐘後，於分析時間40分鐘~50分鐘，施加A液：B液＝80：20(體積比)~10：90(體積比)之梯度，並於A液：B液＝10：90保持直到70分鐘。(Liquid chromatography analysis conditions) The liquid chromatography analysis conditions are as follows. Liquid chromatography analysis device: LC-6AD (liquid feeding unit), CTO-10A (constant temperature bath), SCL-10A (UV), SPD-10AV (UV-VIS detector), SPD-M20A (PDA detector) Column: Shodex RSpak DE-413L Detector: UV (210nm) Eluent composition: A liquid = acetonitrile, B liquid = 0.5% phosphoric acid aqueous solution Mode: Binary gradient Flow rate: 1.0mL/min Constant temperature bath temperature: 35℃ The conditions of the eluent are as follows. In the analysis time 0-15 minutes, set A liquid: B liquid = 10: 90 (volume ratio), in 15-20 minutes, apply A liquid: B liquid = 10: 90 (volume ratio) ~ 50: 50 (volume) Than) the gradient. Furthermore, in the analysis time of 20-25 minutes, apply a gradient of A liquid: B liquid = 50:50 (volume ratio) ~ 80:20 (volume ratio). Maintain liquid A: Liquid B=80:20 (volume ratio) until 40 minutes later, apply liquid A: Liquid B=80:20 (volume ratio) to 10:90 (volume ratio) after the analysis time is 40 minutes to 50 minutes The gradient is maintained at liquid A: liquid B=10:90 until 70 minutes.
又，於上述液體層析，測定環己烷三羧酸，並以絕對檢量法定量試樣中之環己烷三羧酸之量，求環己烷三羧酸在試樣中之質量比例，以100扣減，作為脫水率。 亦即，試樣100g中含有2g未反應之環己烷三羧酸時，則脫水率為98%。In addition, in the above liquid chromatography, the cyclohexanetricarboxylic acid was measured, and the amount of cyclohexanetricarboxylic acid in the sample was quantified by the absolute calibration method to obtain the mass ratio of cyclohexanetricarboxylic acid in the sample , Deduct 100 as the dehydration rate. That is, when 2 g of unreacted cyclohexanetricarboxylic acid is contained in 100 g of the sample, the dehydration rate is 98%.
H-TMAn-S之純度，係藉由將GC純度乘以脫水率算出。 H-TMAn-S(質量%)＝H-TMAn-S之GC純度(質量%)×脫水率(質量%)÷100The purity of H-TMAn-S is calculated by multiplying the GC purity by the dehydration rate. H-TMAn-S (mass%) = GC purity of H-TMAn-S (mass%) × dehydration rate (mass%) ÷ 100
>>含液率之測定>> 從上述乾燥操作所致之質量減少求含液率。 含液率(%)＝[(濕晶之質量-乾晶之質量)/(濕晶之質量)]×100 在此濕晶之質量，係指使用離心分離機，以離心加速度450G旋轉直到不再有濾液之後之濕晶。>>Measurement of liquid content>> Calculate the liquid content from the mass reduction caused by the above-mentioned drying operation. Liquid content (%)=[(quality of wet crystal-quality of dry crystal)/(quality of wet crystal)]×100 The quality of the wet crystals here refers to the wet crystals after the centrifuge is rotated at a centrifugal acceleration of 450G until there is no more filtrate.
>實施例1> 對於上述比較例1獲得之母液中的76質量%的份量，追加H-TMA(255.7g)、乙酸(136.8g)、乙酸酐(129.9g)並實施反應。反應液之各成分係以上述GC分析算出。 以和比較例1同樣的條件進行晶析。環己烷-1,2,4-三羧酸-1,2-酐之產率為70.24mol%。 和比較例1同樣將固體液體分離，測定濕晶之含液率。獲得之結晶中之含液率為8.09質量%。又，獲得之乾晶中之MeHHPA之量為0.045質量%。乾晶中之各成分係以上述GC分析算出。>Example 1> For the amount of 76% by mass in the mother liquor obtained in Comparative Example 1, H-TMA (255.7 g), acetic acid (136.8 g), and acetic anhydride (129.9 g) were added and reacted. The components of the reaction liquid were calculated by the above-mentioned GC analysis. Crystallization was performed under the same conditions as in Comparative Example 1. The yield of cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride was 70.24 mol%. As in Comparative Example 1, the solid and liquid were separated, and the liquid content of the wet crystal was measured. The liquid content in the obtained crystals was 8.09% by mass. In addition, the amount of MeHHPA in the obtained dry crystal was 0.045% by mass. The components in the dry crystal are calculated by the above GC analysis.
>實施例2~6> 使用於比較例1獲得之晶析母液，實施和實施例1同樣的操作，結果示於表1(實施例2~6。實施例2使用實施例1之晶析母液。)。>Examples 2~6> Using the crystallization mother liquor obtained in Comparative Example 1, the same operation as in Example 1 was performed, and the results are shown in Table 1 (Examples 2 to 6. Example 2 used the crystallization mother liquor of Example 1.).
[表1]
依據實施例1~6及比較例1之數據，繪製圖3及圖4之圖。圖3係顯示晶析系之初始狀態之MeHHPA之量與環己烷-1,2,4-三羧酸-1,2-酐之結晶(濕晶)中之含液率之關係之圖。具體而言，橫軸顯示晶析系之初始(晶析反應前)之MeHHPA之量(單位：質量%)，縱軸顯示獲得之濕晶中之含液率(質量%)。圖4係顯示乾晶中之MeHHPA之量與濕晶中之含液率之關係之圖。具體而言，橫軸顯示乾晶中之MeHHPA之量(單位：質量%)，縱軸顯示獲得之濕晶中之含液率(質量%)。Based on the data of Examples 1 to 6 and Comparative Example 1, the graphs in Figs. 3 and 4 are drawn. Figure 3 is a graph showing the relationship between the amount of MeHHPA in the initial state of the crystallization system and the liquid content in the crystal (wet crystal) of cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride. Specifically, the horizontal axis shows the initial amount of MeHHPA (unit: mass %) of the crystallization system (before the crystallization reaction), and the vertical axis shows the liquid content (mass %) in the obtained wet crystal. Figure 4 is a graph showing the relationship between the amount of MeHHPA in the dry crystal and the liquid content in the wet crystal. Specifically, the horizontal axis shows the amount of MeHHPA in the dry crystal (unit: mass %), and the vertical axis shows the liquid content (mass %) in the obtained wet crystal.
由圖3及圖4可知，實施例1~6中，獲得之環己烷-1,2,4-三羧酸-1,2-酐之結晶(濕晶)中之含液率低。又，獲得之環己烷-1,2,4-三羧酸-1,2-酐之結晶(乾晶)中，含有0.025~0.1質量%之4-甲基-1,2-環己烷二羧酸酐。 反觀比較例1中，獲得之環己烷-1,2,4-三羧酸-1,2-酐之結晶(濕晶)中之含液率高。又，獲得之環己烷-1,2,4-三羧酸-1,2-酐之結晶(乾晶)中，幾乎不含4-甲基-1,2-環己烷二羧酸酐。It can be seen from Figures 3 and 4 that in Examples 1 to 6, the obtained cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride crystals (wet crystals) have a low liquid content. In addition, the obtained crystal (dry crystal) of cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride contains 0.025~0.1% by mass of 4-methyl-1,2-cyclohexane Dicarboxylic anhydride. In contrast, in Comparative Example 1, the obtained cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride crystal (wet crystal) has a high liquid content. In addition, the obtained crystals (dry crystals) of cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride contained almost no 4-methyl-1,2-cyclohexanedicarboxylic acid anhydride.
圖1係顯示本發明之環己烷三羧酸酐之結晶之製造方法之一例之方案。 圖2係顯示實施例之各成分之分析方法之方案。 圖3係顯示實施例中，晶析系內之初始MeHHPA(4-甲基-1,2-環己烷二羧酸酐)之量與濕晶中之含液率之關係之圖。 圖4係顯示實施例之乾晶中之MeHHPA之量與濕晶中之含液率之關係之圖。Fig. 1 is a scheme showing an example of the method for producing the crystal of cyclohexanetricarboxylic anhydride of the present invention. Figure 2 shows the scheme of the analysis method of each component of the embodiment. Fig. 3 is a graph showing the relationship between the initial amount of MeHHPA (4-methyl-1,2-cyclohexanedicarboxylic anhydride) in the crystallization system and the liquid content in the wet crystal in the embodiment. Figure 4 is a graph showing the relationship between the amount of MeHHPA in the dry crystal and the liquid content in the wet crystal of the embodiment.
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