New trisphenol derivatives

Abstract

The present invention addresses the problem of providing a novel compound which has satisfactory solubility in solvents, has high storage stability (solution stability) during refrigeration or freeze storage, and is usable as a crosslinking agent. Provided, as a solution, is a substituted trisphenol compound represented by formula (2).

Description

[Technical field]

[0001] The present invention relates to a novel trisphenol derivative having good solubility in a solvent and excellent storage stability. [Background technology]

[0002] Conventionally, phenol-based methylol compounds and methoxymethyl compounds have been used as crosslinking agents to improve the film properties of photosensitive resins. As crosslinking agents, compounds with many crosslinking groups per molecule are considered to be suitable because they have high crosslinking reaction efficiency and stable film properties. For example, a group of compounds represented by the following chemical structure has been reported as methoxymethyl group-containing phenol compounds that have sufficient film hardening performance even in small amounts (for example, Patent Documents 1, 2, etc.). [ka] [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 07-017888 [Patent Document 2] JP 2007-016214 A Summary of the Invention [Problem to be solved by the invention]

[0004] Phenol-based methylol compounds and methoxymethyl compounds undergo crosslinking when stored at temperatures higher than room temperature, and are therefore preferably stored refrigerated or frozen. Solution products using these compounds, such as photosensitive resin compositions (varnishes), photoresists, and paints, are also required to be stored refrigerated from the viewpoint of quality and storage stability during storage, while the raw materials may be previously made into a solution and then used from the viewpoint of production efficiency. The inventors recognized that the compound (x) and compound (y) represented by the above chemical structure have a characteristic of being easily crystallized due to the symmetry of the parent skeleton, and therefore, as shown in the experimental example described below, they have a problem that they do not dissolve in a large amount in a solvent. In addition, they also recognized a problem that even if a desired high-concentration solution can be prepared at room temperature, crystals will precipitate when the solution is refrigerated or frozen, and therefore, when the solution is refrigerated or frozen, only a low-concentration solution that does not precipitate crystals can be prepared, and the amount that can be added as a crosslinker is limited. The present invention has been made against the background of the above-mentioned circumstances, and an object of the present invention is to provide a novel compound that has good solubility in solvents and high storage stability (solubility stability) when stored in a refrigerator or freezer, and can be used as a crosslinking agent. [Means for solving the problem]

[0005] As a result of intensive research into solving the above-mentioned problems, the present inventors discovered that by introducing the flexibility of a mother skeleton containing a linear alkylene group, particularly the mother skeleton of raspberry ketones (4-(hydroxyphenyl)-2-butanone), instead of the mother skeleton of a conventionally known compound (for example, the above-mentioned Patent Documents 1 and 2), crystallization is suppressed and solubility in solvents is improved, thereby completing the present invention. It is believed that this suppression of crystallization and improvement of solubility in solvents are due to the fact that stacking between molecules becomes less likely to occur by introducing the mother skeleton.

[0006] The present invention is as follows. 1. A substituted trisphenol compound represented by the following formula (1): [ka] (In the formula, each R1 independently represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group; R a each independently represents a hydrogen atom or a substituted carbonyl group; R b each independently represents a substituent, n represents an integer of 1 to 2, m represents 0 or an integer of 1 to 3, and p represents an integer of 1 to 6, with the proviso that m+n is an integer of 1 to 4. 2. A substituted trisphenol compound represented by the following formula (2): [ka] (In the formula, each R1 independently represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms or a phenyl group; each R2 independently represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms; n represents an integer of 1 to 2; m represents 0 or an integer of 1 to 3; and p represents an integer of 1 to 6, with the proviso that m+n is an integer of 1 to 4.) 3. A substituted trisphenol compound represented by the following formula (3): [ka] (In the formula, R1's each independently represent a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms or a phenyl group; R3 and R4 each independently represent a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 8 carbon atoms; R3 and R4 may be bonded to each other to form a cyclic secondary amino group having 5 to 10 carbon atoms which may contain an oxygen atom or a sulfur atom as a whole; n represents an integer of 1 to 2; m represents an integer of 0 or 1 to 3; and p represents an integer of 1 to 6, with the proviso that m+n is an integer of 1 to 4.) 4. A substituted trisphenol compound represented by the following formula (4): [ka] (In the formula, each R1 independently represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms or a phenyl group; each R5 independently represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 8 carbon atoms; n represents an integer of 1 to 2; m represents 0 or an integer of 1 to 3; and p represents an integer of 1 to 6, with the proviso that m+n is an integer of 1 to 4.) Effect of the Invention

[0007] The novel compound of the present invention exhibits excellent effects such as good solubility in solvents and high storage stability (solubility stability) during refrigerated or frozen storage. Furthermore, the novel compound of the present invention is useful because it is expected that the use of the compound as a crosslinking agent will enable the creation of photosensitive resins with improved film properties. Furthermore, the novel compound of the present invention can also be used as a curing agent for epoxy resins. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present invention will be described in detail below. <Compound of the Present Invention> The compound of the present invention is a substituted trisphenol compound represented by the following formula (1). [ka] (In the formula, each R1 independently represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group; R a each independently represents a hydrogen atom or a substituted carbonyl group; R b each independently represents a substituent, n represents an integer of 1 to 2, m represents 0 or an integer of 1 to 3, and p represents an integer of 1 to 6, with the proviso that m+n is an integer of 1 to 4. Among the substituted trisphenol compounds represented by the above formula (1), preferred compounds are the substituted trisphenol compounds represented by the above formulas (2) to (4). a is preferably a hydrogen atom or a -COR5 group (R5 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 8 carbon atoms), and R b is preferably any one of an -OR2 group (R2 represents a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms), a -NR3R4 group (R3 and R4 each independently represent a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 8 carbon atoms), or a -OCOR5 group (R5 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 8 carbon atoms).

[0009] R1 in the above formulas (1) to (4) each independently represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or a phenyl group. Among these, a linear or branched alkyl group having 1 to 4 carbon atoms, a cyclohexyl group, or a phenyl group is preferred, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cyclohexyl group is more preferred, and a methyl group or a cyclohexyl group is particularly preferred. In the above formulas (1) to (4), m represents 0 or an integer of 1 to 3. Among these, 0, 1 or 2 is preferable, and 0 or 1 is more preferable. When m is 1, the substitution position of R1 on the benzene ring is preferably the ortho position relative to the hydroxy group or -OCOR5 group. In the above formulas (1) to (4), p represents an integer of 1 to 6. Among these, an integer of 1 to 4 is preferable, 1 or 2 is more preferable, and 2 is particularly preferable. In the above formula (2), R2 each independently represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms. Among these, a linear or branched alkyl group having 1 to 4 carbon atoms is preferred, a methyl group or an ethyl group is more preferred, and a methyl group is particularly preferred. The substitution position of the -CH2OR2 group on the benzene ring in the above formula (2) is preferably the ortho position relative to the hydroxy group. R3 and R4 in the above formula (3) each independently represent a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 8 carbon atoms. Among these, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms is preferred, a linear or branched alkyl group having 1 to 6 carbon atoms is more preferred, a linear or branched alkyl group having 1 to 6 carbon atoms is even more preferred, and a methyl group is particularly preferred. Furthermore, in the case of forming a cyclic secondary amino group having 5 to 10 carbon atoms which may contain an oxygen atom or a sulfur atom as a whole, specific examples include cyclic secondary amino groups represented by the following formulas, which are particularly preferred. [ka] (In the formula, * represents a bonding group.) The substitution position of the -CH2NR3R4 group on the benzene ring in the above formula (3) is preferably the ortho position relative to the hydroxy group. R5 in the above formula (4) each independently represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 8 carbon atoms. Among these, a linear or branched alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 8 carbon atoms is preferred, a linear or branched alkyl group having 1 to 6 carbon atoms, or a phenyl group is more preferred, a linear or branched alkyl group having 1 to 6 carbon atoms, or a phenyl group is even more preferred, and a methyl group is particularly preferred. The substitution position of the -CH2OCOR5 group on the benzene ring in the above formula (4) is preferably the ortho position relative to the -OCOR5 group.

[0010] <Substituted trisphenol compound represented by formula (2)> As the substituted trisphenol compound represented by the above formula (2), which is the compound of the present invention, a preferred compound is a substituted trisphenol compound represented by the following formula (2a) in which the hydroxy group is at the para position, and a more preferred compound is a substituted trisphenol compound represented by the following formula (2b) in which "p" in the following formula (2a) is 2. [ka] (In the formula, R1, R2, m, n, and p are defined as in formula (2).) Specific examples and preferred examples of R1, R2, m, n, and p in the above formula (2a) are the same as those in the above formula (2). [ka] (In the formula, R1, R2, m, and n are defined as in formula (2).) Specific and preferred examples of R1, R2, m, and n in the above formula (2b) are the same as those in the above formula (2).

[0011] Among the more preferred compound group, substituted trisphenol compounds represented by the above formula (2b), the compound group represented by the following chemical structural formula is particularly preferred. [ka] JPEG0007661333000011.jpg45170

[0012] <Substituted trisphenol compound represented by formula (3)> As the substituted trisphenol compound represented by the above formula (3), which is the compound of the present invention, a preferred compound is a substituted trisphenol compound represented by the following formula (3a) in which the hydroxy group is at the para position, and a more preferred compound is a substituted trisphenol compound represented by the following formula (3b) in which "p" in the following formula (3a) is 2. [ka] (In the formula, R1, R3, R4, m, n, and p are defined as in formula (3).) Specific examples and preferred examples of R1, R3, R4, m, n, and p in the above formula (3a) are the same as those in the above formula (3). [ka] (In the formula, R1, R3, R4, m, and n are defined as in formula (3).) Specific examples and preferred examples of R1, R3, R4, m, and n in the above formula (3b) are the same as those in the above formula (3).

[0013] Among the more preferred compound group, substituted trisphenol compounds represented by the above formula (3b), the compound group represented by the following chemical structural formula is particularly preferred. [ka] JPEG0007661333000015.jpg45170

[0014] <Substituted trisphenol compound represented by formula (4)> As the substituted trisphenol compound represented by the above formula (4), which is the compound of the present invention, a preferred compound is a substituted trisphenol compound represented by the following formula (4a) in which the -OCOR5 group is in the para position, and a more preferred compound is a substituted trisphenol compound represented by the following formula (4b) in which "p" in the following formula (4a) is 2. [ka] (In the formula, R1, R5, m, n, and p are defined as in formula (4).) Specific examples and preferred examples of R1, R5, m, n, and p in the above formula (4a) are the same as those in the above formula (4). [ka] (In the formula, R1, R5, m, and n are defined as in formula (4).) Specific and preferred examples of R1, R5, m, and n in the above formula (4b) are the same as those in the above formula (4).

[0015] Among the more preferred compound group, substituted trisphenol compounds represented by the above formula (4b), the compound group represented by the following chemical structural formula is particularly preferred. [ka] JPEG0007661333000019.jpg43170

[0016] <Method of producing the compound of the present invention> The raw material (7) of the compound of the present invention is produced by the condensation reaction of a ketone (5) having a hydroxyphenyl group with a phenol (6), as shown in the following reaction formula. This condensation reaction can be carried out according to known reaction conditions. [ka] (In the formula, R1, m, and p are defined as in formulas (1) to (4).)

[0017] The ketones (5) having a hydroxyphenyl group in the above-mentioned production method can be produced, for example, by the method described in JP-A-51-32532. Specifically, for example, 4-(4-hydroxyphenyl)butan-2-one (CAS Registry Number 5471-51-2), 4-(4-hydroxy-3-methylphenyl)butan-2-one (CAS Registry Number 125101-98-6), 4-(4-hydroxy-2-methylphenyl)butan-2-one (CAS Registry Number 91969-86-7), 4-(4-hydroxy-3-isopropylphenyl)butan-2-one (CAS Registry Number 96713-34-7), 4-(4-hydroxy-3-t-butyl ... Examples of such hydroxyphenyl include 4-(4-hydroxy-3-cyclohexylphenyl)butan-2-one (CAS Registry Number 54685-33-5), 4-(4-hydroxy-3-cyclohexylphenyl)butan-2-one (CAS Registry Number 60561-24-2), 4-(4-hydroxy-2,6-dimethylphenyl)butan-2-one (CAS Registry Number 125102-00-3), 4-(4-hydroxy-2,3-dimethylphenyl)butan-2-one (CAS Registry Number 125102-01-4), 4-(4-hydroxy-3,5-dimethylphenyl)butan-2-one (CAS Registry Number 91374-58-2), and 4-(4-hydroxy-3,5-dibutylphenyl)butan-2-one (CAS Registry Number 5082-72-4). Among these, 4-(4-hydroxyphenyl)butan-2-one is particularly preferred.

[0018] The raw material (7) of the compound of the present invention can also be produced by reacting a halogenated ketone (8) with a phenol (6) as shown in the following reaction scheme. This reaction can be carried out under known reaction conditions. [ka] (In the formula, R1, m, and p are defined as in the formulas (1) to (4), and X represents a halogen atom.)

[0019] Specific examples of the halogenated ketones (8) in the above production method include fluoroacetone, chloroacetone, bromoacetone, iodoacetone, 4-fluoro-2-butanone, 4-chloro-2-butanone, 4-bromo-2-butanone, 4-iodo-2-butanone, 5-chloro-2-pentanone, 5-bromo-2-pentanone, 5-iodo-2-pentanone, 6-chloro-2-hexanone, 6-bromo-2-hexanone, 6-iodo-2-hexanone, 7-chloro-2-pentanone, 7-bromo-2-pentanone, 7-iodo-2-pentanone, 8-chloro-2-octanone, 8-bromo-2-octanone, and 8-iodo-2-octanone.

[0020] <Manufacturing method 1> As a method 1 for producing the compound of the present invention, a method via a methylol compound will be specifically described using the method for producing the preferred compound shown below as an example. The compounds in the following reaction scheme are hereinafter referred to as "Compound (A1)", "Compound (B1)" and "Compound (C1)". [ka] (Process I) The first step (I) will now be described. The compound (A1) is used as a raw material, and in the presence of a basic catalyst, 1 mole of the compound (A1) is reacted with 6 to 12 moles, preferably 9 moles, of formaldehyde in an aqueous solvent or a mixed solvent of water and an organic solvent, and the resulting reaction product is then neutralized to obtain the compound (A1). In the above-mentioned production method, as the formaldehyde, for example, a commercially available 35% aqueous formalin solution can be used as it is, or paraformaldehyde or trioxane, which acts similarly to formaldehyde in the presence of water, can also be used, but it is preferable to use formalin. Examples of the basic catalyst include alkali metal or alkaline earth metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, and magnesium hydroxide, and strong organic bases such as tetramethylammonium hydroxide. Among them, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and strong organic bases such as tetramethylammonium hydroxide are preferred, and 10 to 40 wt % aqueous solutions of these bases are preferably used. In step (I), the basic catalyst is preferably used in an amount of 2.5 to 3.5 times by mol, more preferably 3 times by mol, relative to the compound (A1) as the raw material.

[0021] The reaction in step (I) is usually carried out in an aqueous solvent or a mixed solvent of water and an organic solvent. As long as the aqueous alkaline solution of the basic catalyst partially or completely dissolves the raw material compound (A1) and the reaction mixture is stirrable, no particular solvent is required. However, when a solvent is required, the amount of the solvent is usually preferably in the range of about 1 to 5 times, more preferably about 2 to 3 times, by weight, the raw material compound (A1). As the organic solvent, for example, alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butanol, ethylene glycol, ethylene glycol monomethyl ether, diethylene glycol, carbitol, etc., aromatic hydrocarbons such as toluene, xylene, etc., and water-soluble aprotic polar solvents such as dimethyl sulfoxide, N-methylpyrrolidone, dimethylformamide, etc. can be used within the range that does not impair the solubility of the aqueous solvent mixture of the basic catalyst and the raw material compound (A1). The reaction in step (I) is usually carried out for about 1 to 72 hours, preferably about 4 to 16 hours, at a temperature usually in the range of 20 to 50° C., preferably in the range of 25 to 40° C., more preferably in the range of 30 to 35° C. If the reaction temperature is lower than 20° C., the reaction proceeds slowly, whereas if it is higher than 50° C., a large amount of various undesirable by-products such as polymeric impurities is produced, which is not preferable.

[0022] In order to separate and recover the target compound (B1) from the reaction mixture obtained after the reaction of the raw material compound (A1) with formaldehyde in the presence of a basic catalyst, an acid such as sulfuric acid is added to the reaction mixture after the reaction is completed to neutralize the target alkali salt and the alkali catalyst. Next, in order to separate and remove the aqueous layer, a solvent that can be separated from water, such as aromatic hydrocarbons such as toluene and xylene, is added as necessary, and then the aqueous layer is separated. After washing the obtained oil layer with water, the solvent and low boiling point compounds such as formaldehyde are distilled off from the oil layer to obtain the target compound (B1). The resulting compound (B1) may be purified, but is preferably used as is in the next step (II).

[0023] (Process II) The next step (II) will be described below. The compound (B1) obtained in the above step (I) can be used as a raw material and reacted with methanol in the presence of an acid catalyst to obtain the target compound (C1). Here, the methoxymethyl group of compound (C1) can be converted to various alkoxymethyl groups by reacting a saturated aliphatic alcohol having 2 to 4 carbon atoms, such as ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, etc., instead of methanol. As the acid catalyst, concentrated sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, cation exchange resin (acid type), oxalic acid, etc. are preferably used. More preferably, it is an inorganic strong acid such as concentrated sulfuric acid. The acid catalyst is usually used in the range of 20 to 40% by weight, preferably 30% by weight, based on the compound (B1). If the acid catalyst is less than 20% by weight, the reaction proceeds slowly, and if it exceeds 40% by weight, the reaction proceeds too much and a large amount of impurities are generated, which is not preferable. The above-mentioned methanol usually serves as a reaction solvent and is used in excess relative to the compound (B1). The amount used is not particularly limited, but is usually in the range of 6 to 12 times by weight, preferably 9 times by weight, relative to the compound (B1).

[0024] The reaction temperature in step (II) is usually in the range of 40 to 70° C., preferably in the range of 50 to 65° C., and more preferably in the range of 55 to 60° C. If the reaction temperature is lower than 40° C., the formation of polymers takes precedence, which is undesirable, whereas if the reaction temperature is higher than 70° C., the reaction proceeds too quickly and a large amount of polymers is formed, which is undesirable. The reaction time is usually about 1 to 240 hours, and preferably about 5 to 100 hours. After the reaction is completed, the target compound (C1) can be isolated from the resulting reaction mixture according to a conventional method. For example, after the reaction is completed, the resulting reaction mixture is neutralized using an alkali such as an aqueous sodium hydroxide solution, and then excess methanol, which also serves as a reaction solvent, is removed by distillation or the like as necessary, and the salt produced by neutralization is filtered off to obtain the target crude product. If necessary, this crude product can be dissolved in a solvent such as an aromatic hydrocarbon such as toluene or xylene, and washed with water several times, and then the aqueous layer can be separated to remove inorganic salts. If further purification is required, it may be separated and purified by column chromatography.

[0025] <Manufacturing method 2> As a second method for producing the compound of the present invention, a method via an aminomethyl compound and an acetyl compound will be described with reference to the reaction scheme of the preferred compound shown below. The compounds in the reaction scheme below are referred to as "compound (D1)" and "compound (E1)" in addition to the aforementioned "compound (A1)" and "compound (C1)". [ka]

[0026] (Process III) The first step (III) will now be described. Step (III) is a step of using compound (A1) as a raw material and reacting it with formaldehyde and dimethylamine in a solvent to obtain compound (D1). This reaction can be easily carried out by a method similar to the known Mannich reaction. The formaldehyde may be an aqueous formaldehyde solution or paraformaldehyde. In addition, if a secondary amine such as diethylamine, dibutylamine, diisopropylamine, pyrrolidine, piperidine, piperazine, morpholine, or oxazolidine is used instead of dimethylamine, the dimethylamino group of compound (D1) can be changed to various amino groups. In this step (III), it is preferable to add acetic acid as a catalyst since it accelerates the reaction. However, if the amount of acetic acid added exceeds 1 mole per mole of dimethylamine, it is not preferable since it actually slows down the reaction. In this step (III), the amounts of formaldehyde and dimethylamine used relative to the raw material compound (A1) are preferably stoichiometric or more. Specifically, the amount of dimethylamine used relative to the raw material compound (A1) is preferably in the range of 6 to 12 molar times, more preferably in the range of 8 to 10 molar times. Similarly, the amount of formaldehyde used relative to the raw material compound (A1) is preferably in the range of 6 to 12 molar times, more preferably in the range of 8 to 10 molar times. A reaction solvent may or may not be used during the reaction. When a reaction solvent is used, the reaction solvent is not particularly limited as long as it is a solvent known for the reaction, and specific examples include water, ether solvents such as diethyl ether, dibutyl ether, and tetrahydrofuran, alcohol solvents such as methanol, ethanol, propanol, and butanol, aromatic hydrocarbon solvents such as toluene and xylene, ketone solvents such as acetone and methyl isobutyl ketone, ester solvents such as ethyl acetate and γ-butyrolactone, nitrile solvents such as acetonitrile, and aprotic polar solvents such as N-methylpyrrolidone, N-methyl-2-pyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. Such solvents may be used alone or in combination of two or more. The amount of the solvent used is not particularly limited, but is preferably in the range of 0.5 to 20 times by weight, more preferably 1 to 5 times by weight, relative to the compound (A1) as the raw material.

[0027] The reaction temperature in step (III) is preferably in the range of 30 to 100° C., more preferably in the range of 60 to 90° C., and even more preferably in the range of 75 to 80° C., and may be appropriately selected within the above temperature range. If the reaction temperature is lower than 30° C., the reaction proceeds slowly and does not reach completion, whereas if the reaction temperature is higher than 100° C., raw materials such as dimethylamine are vaporized, which is undesirable. The reaction time is usually about 0.5 to 24 hours, and preferably about 1 to 10 hours. In the step (III), the order of adding the raw materials is not particularly limited. For example, the raw materials (A1), dimethylamine, and aqueous formaldehyde solution, and optionally a solvent, may be added simultaneously, or the raw materials (A1) and dimethylamine may be added, and then the aqueous formaldehyde solution may be added dropwise thereto. After completion of step (III) of the reaction of the raw material compound (A1) with formaldehyde and dimethylamine, the target reaction product compound (D1) can be separated and recovered from the reaction mixture obtained by a known method and used as the raw material for the next step (IV). For example, after the reaction is completed, a solvent that separates from water, such as an aromatic hydrocarbon such as toluene or xylene, is added to the reaction mixture as necessary, and then the aqueous layer is separated. Water is added to the resulting oil layer to wash the oil layer, and the solvent is removed from the oil layer by distillation or the like as necessary, and the resulting crude product containing the target substance may be used as it is as a raw material for the next step. Compound (D1) may also be isolated and purified from the oil layer obtained by treatment after the reaction is completed.

[0028] (Process IV) The next step (IV) will be described below. Step (IV) is a step of converting the compound (D1) obtained in the above step (III) into the compound (E1). The reaction in step (IV) can be easily carried out in accordance with a known method of reacting the compound (D1) with acetic anhydride. Here, the acetyl group of the compound (E1) can be changed to various acyloxy groups by reacting a carboxylic acid anhydride, such as propionic anhydride, butyric anhydride, or benzoic anhydride, instead of acetic anhydride. In the step (IV), the amount of acetic anhydride used relative to the compound (D1) is preferably a stoichiometric amount or more, specifically, it is preferably in the range of 9 to 15 times by mol, more preferably 12 times by mol. Since acetic anhydride also serves as a solvent during the reaction, it is not necessary to use other solvents, but non-aqueous solvents such as toluene and xylene may be used as required for the reaction procedure. The reaction temperature is preferably in the range of 80 to 130°C, more preferably in the range of 100 to 130°C, and particularly preferably in the range of 120 to 125°C. If the reaction temperature is lower than 80°C or higher than 130°C, a large amount of impurities is produced, which is not preferable. The reaction time is usually about 0.5 to 40 hours, and preferably about 5 to 20 hours. After the reaction is completed, the target compound (E1) can be separated and recovered from the reaction mixture by a known method, and can be used as a raw material in the next step (V). For example, after the reaction is completed, unreacted acetic anhydride and the solvent added as necessary are distilled from the reaction mixture to obtain a crude product containing the target compound, which can be used as a raw material in the next step (V) as it is, or the crude product obtained can be isolated and purified to obtain compound (E1).

[0029] (Process V) The next step (V) will be described below. In step (V), the compound (E1) obtained in step (IV) is reacted with methanol in the presence of a catalyst to obtain the target compound (C1). Here, the methoxymethyl group of the compound (C1) can be changed to various alkoxymethyl groups by reacting a saturated aliphatic alcohol having 2 to 4 carbon atoms, such as ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, etc., instead of methanol. The amount of methanol used in step (V) is preferably a molar ratio of stoichiometric or more to compound (E1), and is usually used in excess of compound (E1) to serve as a reaction solvent. The amount of methanol used is not particularly limited as long as it is stoichiometric or more, but specifically, for example, it is in the range of 6 to 12 times by weight, and preferably 7 times by weight. Specific examples of the catalyst used in step (V) include acid catalysts such as sulfuric acid and p-toluenesulfonic acid, alkali catalysts such as potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, and sodium methylate, and carboxylates such as sodium acetate and potassium acetate. Acid catalysts are preferred. The amount of catalyst used varies depending on the type of catalyst, but in the case of sulfuric acid, for example, it is preferably in the range of 1 to 20 mol%, more preferably 10 mol%, relative to compound (E1). If the amount of catalyst used exceeds 20 mol%, the reaction proceeds too far and a large amount of impurities is generated, which is not preferred. Since the saturated aliphatic alcohol having 1 to 4 carbon atoms also serves as a solvent during the reaction, it is usually not necessary to use other solvents, but a non-aqueous solvent such as toluene or xylene may be used if necessary for the reaction procedure. The reaction temperature is preferably in the range of 40 to 70° C., more preferably in the range of 50 to 65° C., and particularly preferably in the range of 55 to 60° C. If the reaction temperature is lower than 40° C., the formation of polymers takes precedence, which is undesirable, whereas if it is higher than 70° C., the reaction proceeds too quickly and a large amount of polymers is formed, which is undesirable. The reaction time is usually about 1 to 240 hours, and preferably about 5 to 100 hours. In the step (V), the order of adding the raw materials is not particularly limited. For example, the compound (E1), methanol, and catalyst may be added simultaneously, or the methanol and catalyst may be mixed and then the compound (E1) may be added thereto.

[0030] After the step (V) is completed, the target compound (C1) can be separated and purified from the resulting reaction mixture in a conventional manner, and isolated as a crude product or a high-purity product. For example, if an acid catalyst is used after the reaction is completed, an alkali is added to the reaction mixture to neutralize it, and excess methanol, etc. is distilled off as necessary, and then a solvent that separates from water is added to wash the mixture, and the solvent is removed by distillation, etc. as necessary, to obtain the target product as a crude product. In addition, the crude product can be further purified by column chromatography, etc. to obtain a high-purity compound (C1).

[0031] The substituted trisphenol compounds represented by the above formula (2), which are the compounds of the present invention, and particularly the substituted trisphenol compounds represented by the above formula (2b), are a group of compounds useful as crosslinking agents for photosensitive resins. The substituted trisphenol compounds represented by the above formula (3), which are the compounds of the present invention, are important intermediates in producing the substituted trisphenol compounds represented by the above formula (2). Furthermore, the substituted trisphenol compounds represented by the above formula (4), which are the compounds of the present invention, are important intermediates in producing the substituted trisphenol compounds represented by the above formula (2), and particularly the substituted trisphenol compounds represented by the above formula (4b) are a group of compounds useful as curing agents for epoxy resins. EXAMPLES

[0032] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The analysis method is as follows. <Analytical equipment and analysis conditions> (1) Analytical conditions for compound (B1) and compound (B2) Measurement equipment: Shimadzu HPLC LC-20 series (Shimadzu Corporation) Pump: LC-20AT Column oven: CTO-20A Detector: SPD-20A (HPLC), cell length 1 cm Column: Shim-pack CLC-ODS (column 6.0 x 150 mm, particle size 5 μm, manufactured by Shimadzu GLC Co., Ltd.) Oven temperature: 50℃ Flow rate: 1.0ml / min Mobile phase: (i) 0.2 vol% acetic acid in water, (ii) MeOH Gradient conditions: (i) volume % (time from start of analysis) 30%(0min)→82.5%(30min)→100%(35min)→100%(45min) Detection wavelength: 280nm Sample concentration: 50mg / 50ml Sample injection volume: 20 μl (2) Analytical conditions for compounds (C1), (C2), (E1), and (E2) Measurement equipment: Shimadzu HPLC LC-20 series (Shimadzu Corporation) Pump: LC-20AT Column oven: CTO-20A Detector: SPD-20A (HPLC), cell length 1 cm Column: Shim-pack CLC-ODS (column 6.0 x 150 mm, particle size 5 μm, manufactured by Shimadzu GLC Co., Ltd.) Oven temperature: 50℃ Flow rate: 1.0ml / min Mobile phase: (i) 0.2 vol% acetic acid in water, (ii) MeOH Gradient conditions: (i) volume % (time from start of analysis) 50%(0min)→100%(30min)→100%(45min) Detection wavelength: 280nm Sample concentration: 50mg / 50ml Sample injection volume: 20 μl

[0033] (3) Analytical conditions for compound (D1) and compound (D2) Measurement equipment: Shimadzu HPLC LC-20 series (Shimadzu Corporation) Pump: LC-20AT Column oven: CTO-20A Detector: SPD-20A (HPLC), cell length 1 cm Column: Shim-pack CLC-ODS (column 6.0 x 150 mm, particle size 5 μm, manufactured by Shimadzu GLC Co., Ltd.) Oven temperature: 50℃ Flow rate: 1.0ml / min Mobile phase: (i) 0.1vol% phosphoric acid water, (ii) MeOH Gradient conditions: (i) volume % (time from start of analysis) 5%(0min)→100%(30min)→100%(45min) Detection wavelength: 280nm Sample concentration: 50mg / 50ml Sample injection volume: 20 μl (4) Solubility measurement, comparative compound (x), (y) analysis conditions Measurement equipment: Shimadzu UFLC LC-20 series (manufactured by Shimadzu Corporation) Pump: LC-20AD Column oven: CTO-20A Detector: SPD-20A (UFLC), cell length 5mm Column: HALO-C18 (column 3.0 x 75 mm, particle size 2.7 μm, manufactured by Advanced Materials Technology) Oven temperature: 50℃ Flow rate: 0.7ml / min Mobile phase: (i) 0.2 vol% acetic acid in water, (ii) MeOH Gradient conditions: (i) volume % (time from start of analysis) 50%(0min)→100%(7.5min)→100%(10min) Detection wavelength: 280nm Sample concentration: compound (x) 50 mg / 50 ml, compound (y) 120 mg / 50 ml Sample injection volume: 5 μl

[0034] <Example 1: Synthesis of compound (B1): Step (I)> Step (I): Compound (A) was added to a 2 L four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser. 1 80.0g (0.24mol) of 15% sodium hydroxide aqueous solution was charged, and 191.4g (0.72mol) of 15% sodium hydroxide aqueous solution was added dropwise over 1 hour while maintaining the temperature at 25-30°C, and the mixture was stirred at 25-30°C for 11 hours. The compound (B1) in the reaction solution was 85% (HPLC area%). The reaction solution was added to a mixed solvent of methyl ethyl ketone and toluene, and dilute sulfuric acid was added dropwise thereto and stirred to neutralize. Thereafter, the aqueous layer was separated, and distilled water was added to the obtained oil layer, stirred, washed with water, and the aqueous layer was separated and removed. Furthermore, the obtained oil layer was washed with water twice in the same manner, and the obtained oil layer was concentrated under reduced pressure to distill off the solvent, and 123.1g of compound (B1) was obtained. The obtained compound (B1) was purified by preparative HPLC to obtain compound (B1) with a purity of 98.6% (HPLC area%). The analysis results are shown below. Molecular weight of compound (B1) (liquid chromatography mass spectrometry / atmospheric pressure chemical ionization method): 513.2 (MH) - 1 H-NMR (400MHz, Methanol-d4 / TMS): δ1.65(s,3H),2.27-2.34(m,4H),4.65(s,12H),4.89(br.s,9H),6.87(s,2H),7.03(s,4H).

[0035] <Example 2: Synthesis of compound (C1): Step (I) to Step (II)> Step (I): 80.0g (0.24mol) of compound (A1) and 191.4g (0.72mol) of 15% aqueous sodium hydroxide solution were charged into a 2L four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser, and 184.6g (2.15mol) of 35% formalin was added dropwise over 1 hour while maintaining the temperature at 25-30°C, and stirring was performed at 25-30°C for 11 hours. Compound (B1) in the reaction solution was 85% (HPLC area%). The reaction solution was added to a mixed solvent of methyl ethyl ketone and toluene, and neutralized by dropping dilute sulfuric acid thereto and stirring. Thereafter, the aqueous layer was separated, and distilled water was added to the obtained oil layer and stirred, followed by washing with water, and the aqueous layer was separated and removed. Furthermore, the obtained oil layer was subjected to the same water washing operation twice, and the obtained oil layer was concentrated under reduced pressure to distill off the solvent. Step (II): Methanol was added to the obtained concentrate to distill off the solvent, and 1107.9 g of methanol and 36.9 g of 98% sulfuric acid were added, and the internal temperature was raised to 58-60°C and stirred for 16 hours. The compound (C1) in the reaction solution was 74.5% (HPLC area%). Next, 16% aqueous sodium hydroxide solution and 75% phosphoric acid were added to the obtained reaction-terminated liquid, and methanol and the like were distilled off, and then toluene and water were added, and the aqueous layer was separated after stirring, and the toluene was distilled off by reduced pressure distillation to obtain compound (C1) with a purity of 74.4% (HPLC area%).

[0036] <Example 3: Synthesis of compound (D1): Step (III)> Step (III): 250g (0.75mol) of compound (A1), 250.1g of 2-propanol, and 513.4g (5.98mol) of 35% formalin were added to a 3L four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser, and 537.7g (5.96mol) of 50% aqueous dimethylamine solution was added to the liquid, and the mixture was stirred for 3 hours while maintaining the internal temperature at 80-85°C. Compound (D1) in the reaction liquid was 96% (HPLC area%). The reaction solution was then distilled, toluene was added to the distillation residue, and the oil layer was washed twice with water. A Dean-Stark tube was then connected and refluxed to remove water from the system. Toluene was then removed by reduced pressure distillation to obtain compound (D1) with a purity of 95.0% (HPLC area%). The analysis results are shown below. Molecular weight (LC / MS / ATC): 675.5 (MH) - 1 H-NMR(400MHz, Methanol-d4 / TMS): δ1.62(s,3H),2.22(s,24H),2.27-2.31(m,16H),3.51(s,4H),3.52(s,8H),4.93(br.s,3H),6.76(s,2H),6.91(s,4H).

[0037] <Example 4: Synthesis of compound (E1): Step (III) to Step (IV)> Step (III): 250g (0.75mol) of compound (A1), 250.1g of 2-propanol, and 513.4g (5.98mol) of 35% formalin were added to a 3L four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser, and 537.7g (5.96mol) of 50% aqueous dimethylamine solution was added to the liquid, and the mixture was stirred for 3 hours while maintaining the internal temperature at 80-85°C. Compound (D1) in the reaction liquid was 96% (HPLC area%). The reaction mixture was then distilled, toluene was added to the distillation residue, and the oil layer was washed twice with water. A Dean-Stark tube was then connected and reflux was carried out to remove water from the system. Step (IV): The internal temperature was then cooled to 78°C, and 918.0g (12.0mol) of acetic anhydride was added over 2 hours. After the addition was completed, the internal temperature was kept at 120-125°C while stirring for 3 hours. The compound (E1) in the reaction solution was 92% (HPLC area%). Next, the unreacted acetic anhydride and the like were distilled off from the resulting reaction-completed solution under reduced pressure, and compound (E1) with a purity of 92.9% (HPLC area%) was obtained. The analysis results are shown below. Molecular weight (LC-MS / ATC): 915.3 (M+Na) + 1 H-NMR(400MHz,Methanol-d4 / TMS):δ1.75(s,H),1.97(s,12H),2.00(s,6H),2.28(s,3H) ),2.30(s,6H),2.39-2.48(m,4H),5.00(s,4H),5.01(s,8H),7.22(s,2H),7.34(s,4H).

[0038] <Example 5: Synthesis of Compound (C1): Step (III) → Step (IV) → Step (V)> Step (III): 250g (0.75mol) of compound (A1), 250.1g of 2-propanol, and 513.4g (5.98mol) of 35% formalin were added to a 3L four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser, and 537.7g (5.96mol) of 50% aqueous dimethylamine solution was added to the liquid, and the mixture was stirred for 3 hours while maintaining the internal temperature at 80-85°C. Compound (D1) in the reaction liquid was 96% (HPLC area%). The reaction mixture was then distilled, toluene was added to the distillation residue, and the oil layer was washed twice with water. A Dean-Stark tube was then connected and reflux was carried out to remove water from the system. Step (IV): The internal temperature was then cooled to 78° C., and 918.0 g (12.0 mol) of acetic anhydride was added over 2 hours. The internal temperature was then kept at 120-125° C. while stirring for 3 hours. The compound (E1) in the reaction solution was 92% (HPLC area %). Step (V): The reaction solution was then distilled under reduced pressure to remove unreacted acetic anhydride, etc., and cooled. At about 50° C., 4,687.7 g of methanol and 14.3 g (0.075 mol) of paratoluenesulfonic acid monohydrate were added, and the mixture was stirred for 11 hours while maintaining the internal temperature at 59-60° C. The compound (C1) in the reaction solution was 98.0% (HPLC area %). Next, 16% sodium hydroxide and 75% phosphoric acid were added to the resulting reaction solution, and methanol and the like were removed by distillation. Toluene and water were then added, and the aqueous layer was separated after stirring. After that, toluene was removed by vacuum distillation, and ethyl lactate, which is commonly used as a resist solvent, was added and redistilled, and ethyl lactate was added again to adjust the solid content concentration to 42.9% (calculated by quantifying ethyl lactate using the HPLC absolute calibration curve), and the yield was calculated using this. An oily compound (C1) was obtained with a purity of 97.5% (HPLC area%) and a yield of 95 mol% (relative to compound (A1)). The analysis results are shown below. Molecular weight (LC / ATC): 597.3 (MH) - 1 H-NMR(400MHz,Methanol-d4 / TMS):δ1.62(s,3H),2.27(br.s,4H),3.34(s,12H), 3.37(s,6H),4.48(s,4H),4.49(s,8H),4.88(br.s,3H),6.88(s,2H),7.04(s,4H).

[0039] <Example 6: Synthesis of compound (D2): Step (III)> [ka] Step (III): In a 500 mL four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser, 30 g (0.06 mol) of the above compound (A2), 30.0 g of 2-propanol, and 39.8 g (0.46 mol) of 35% formalin were added. add し、 40.1 g (0.44 mol) of 50% dimethylamine was added to the liquid, and the mixture was stirred for 13.5 hours while maintaining the internal temperature at 80 to 85° C. The compound (D2) content in the reaction liquid was 97.1% (HPLC area %). The reaction mixture is then distilled, and the distillation residue is Slag Toluene was added to the mixture, and the oil layer was washed twice with water. A Dean-Stark apparatus was then connected and reflux was performed to remove water from the system. Toluene was then removed by vacuum distillation to obtain compound (D2) with a purity of 98.6% (HPLC area%). The analysis results are shown below. Molecular weight (LC-MS / ATC): 727.6 (M+H) + 1 H-NMR(400MHz,Methanol-d4 / TMS):δ1.21-1.48(m,10H),1.60(s,3H),1.73-1.82(m,1 0H),2.24-2.32(m,28H),2.93(t,2H),3.57(d,8H),4.90(br.s,3H),6.74-6.86(m,6H).

[0040] <Example 7: Synthesis of compound (E2): Step (III) to Step (IV)> [ka] Step (III): In a 500 mL four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser, 30 g (0.06 mol) of the above compound (A2), 30.0 g of 2-propanol, and 39.8 g (0.46 mol) of 35% formalin were added. add し、 40.1 g (0.44 mol) of 50% dimethylamine was added to the liquid, and the mixture was stirred for 13.5 hours while maintaining the internal temperature at 80 to 85° C. The compound (D2) content in the reaction liquid was 97.1% (HPLC area %). The reaction mixture is then distilled, and the distillation residue is Slag Toluene was added and the oil layer was washed twice with water, after which a Dean-Stark tube was connected and reflux was carried out to remove water from the system. Step (IV): The internal temperature was then cooled to 80°C, and 74.2g (0.73mol) of acetic anhydride was added over 2 hours. After the addition was completed, the internal temperature was kept at 120-125°C while stirring for 18.5 hours. The compound (E2) in the reaction solution was 90.7% (HPLC area%). Next, the unreacted acetic anhydride and the like were distilled from the resulting reaction-completed solution under reduced pressure to obtain compound (E2) with a purity of 90.6% (HPLC area%). The analysis results are shown below. Molecular weight (LC-MS / ATC): 913.5 (M+H) + 1 H-NMR(400MHz,Methanol-d4 / TMS):δ1.23-1.43(m,10H),1.72-1.85(m,13H),2.0 2(d,12H),2.34(d,9H),2.45(s,4H),2.54(t,2H),5.03(d,8H),7.15-7.23(m,6H).

[0041] <Example 8: Synthesis of compound (C2): Step (III) → Step (IV) → Step (V)> [ka] Step (III): In a 500 mL four-neck flask equipped with a thermometer, a stirrer, a dropping funnel, and a condenser, 30 g (0.06 mol) of the above compound (A2), 30.0 g of 2-propanol, and 39.8 g (0.46 mol) of 35% formalin were added. add し、 40.1 g (0.44 mol) of 50% dimethylamine was added to the liquid, and the mixture was stirred for 13.5 hours while maintaining the internal temperature at 80 to 85° C. The compound (D2) content in the reaction liquid was 97% (HPLC area %). The reaction mixture is then distilled, and the distillation residue is Slag Toluene was added and the oil layer was washed twice with water, after which a Dean-Stark tube was connected and reflux was carried out to remove water from the system. Step (IV): The internal temperature was then cooled to 80° C., and 74.2 g (0.73 mol) of acetic anhydride was added over 2 hours. After the addition was completed, the mixture was stirred for 18.5 hours while maintaining the internal temperature at 120 to 125° C. The compound (E2) in the reaction solution was 90.7% (HPLC area %). Step (V): The resulting reaction solution was distilled under reduced pressure to remove unreacted acetic anhydride, etc., and then cooled. At about 50° C., 246.1 g of methanol and 1.0 g (0.005 mol) of paratoluenesulfonic acid monohydrate were added, and the mixture was stirred for 10 hours while maintaining the internal temperature at 60° C. The content of compound (C2) in the reaction solution was 95.9% (HPLC area %). Next, 16% sodium hydroxide and 75% phosphoric acid were added to the resulting reaction solution, and methanol and the like were removed by distillation. Then, butyl acetate and water were added, and the aqueous layer was separated after stirring. Then, butyl acetate was removed by vacuum distillation to obtain an oily compound (C2) with a purity of 97.1% (HPLC area%). The yield was 83.8 mol% (relative to compound (A2)). The analysis results are shown below. Molecular weight (LC / ATC): 673.5 (MH) - 1 H-NMR(400MHz,Methanol-d4 / TMS):δ1.22-1.45(m,10H),1.62(s,3H),1.71-1.80(m,10H) ,2.27(s,4H),2.95(t,2H),3.38(d,12H),4.52(d,8H),4.90(br.s,3H),6.90-6.96(m,6H).

[0042] <Evaluation test 1: Solubility at 30℃> The solubilities of the compounds (C1) and (C2) obtained in the examples, and the following two compounds reported as crosslinking agents having six functional groups, in ethyl lactate, which is commonly used as a resist solvent, at 30°C were measured. The following compounds are referred to as "comparative compound (x)" and "comparative compound (y)". Comparative compound (x) and comparative compound (y) were synthesized with reference to the synthesis methods described in Synthesis Examples 3 and 4 of Patent Document 2. [ka]

[0043] (Evaluation method) Add a cross stir bar and 10g of ethyl lactate to a 100ml test tube. CompareAfter adding 10 g of compound (x) (or (y)), a bent tube was attached, and a pre-temperature-controlled water bath was set at 30°C under nitrogen sequestering, and the mixture was stirred with a stirrer for 3 hours. After stirring for 3 hours, the internal liquid was sampled with a pipette, and the supernatant obtained by filtering solids from the sampled liquid through a syringe filter was placed in a 50 ml measuring flask. This was diluted to the 50 ml mark with HPLC-grade methanol, and analyzed with a high-performance liquid chromatography analyzer. From the results obtained, Compare Using the peak area of ​​compound (x) (or (y)), Compare Quantify compound (x) (or (y)) and measure its solubility (= Compare Quantitative value (mg) of compound (x) or (y) / (weight (mg) placed in a 50 ml measuring flask through a syringe filter) - Compare The quantitative amount (mg) of compound (x) or (y) was calculated. Calibration curve creation method: Compare Compound (x) (or (y)) is analyzed by HPLC; Compare The peak area of ​​compound (x) (or (y)) is plotted on the horizontal axis, the concentration (mg / 50 ml) on the vertical axis, and the approximation line obtained with "intercept = 0" is Compare This was used as a calibration curve for compound (x) (or (y)).

[0044] [Table 1]

[0045] As shown in Table 1, it was revealed that compound (C1), which is a compound of the present invention, has about twice the solubility in ethyl lactate as compared with comparative compound (x), which has been reported to be useful as a crosslinking agent, and has slightly lower solubility in ethyl lactate as compared with comparative compound (y), which has been reported to be useful as a crosslinking agent. In addition, the solubility of the compound (C2) of the present invention is 100.0 g / 100 g or more, which is very high. It was found that the solubility in ethyl lactate is more than twice as high as that of the comparative compound (x), and that the solubility in ethyl lactate is higher than that of the comparative compound (y).

[0046] <Evaluation test 2: Low temperature storage stability (dissolution stability)> In the above "Evaluation Test 1", the solubility of the compound (C1) of the present invention in ethyl lactate at 30°C was comparable to that of the comparative compound (y), and the solubility of the compound (C2) of the present invention was higher than that of the comparative compound (y). 2 ) was used to conduct low-temperature storage tests of ethyl lactate solutions at refrigerated (5°C) and frozen (-5°C).

[0047] (Evaluation method) In a 50 ml screw tube, 4.29 g of the compound (C1) of the present invention and 5.71 g of ethyl lactate were mixed, and the mixture was placed in a water bath set at 30° C. and stirred by shaking by hand. Complete dissolution was confirmed by visual inspection, and an ethyl lactate solution with a concentration of compound (C1) of 42.9% by weight was prepared. Similarly to the compound (C1), an ethyl lactate solution containing the compound (C2) at a concentration of 40% by weight, an ethyl lactate solution containing the compound (C2) at a concentration of 50% by weight, Compare An ethyl lactate solution containing compound (y) at a concentration of 40% by weight was prepared. The above solution was subjected to a solution storage test for 30 days in a refrigerator (5°C) and a freezer (-5°C). The evaluation results are shown in Table 2 according to the following evaluation criteria. [Evaluation Criteria] ◯: Completely dissolved, and no crystal precipitation or separation of oily components can be visually confirmed. ×: Crystal precipitation or separation of oily components was visually observed.

[0048] [Table 2]

[0049] As shown in Table 2, it was confirmed that the compounds of the present invention, Compound (C1) and Compound (C2), remained as transparent solutions without crystallization even at a refrigerated temperature of 5°C or a frozen temperature of -5°C, and even after a storage period of 30 days. On the other hand, it was revealed that comparative compound (y), which has a slightly higher solubility at 30° C. than that of compound (C1), the compound of the present invention, precipitates crystals at both the refrigeration temperature of 5° C. and the freezing temperature of −5° C., despite its low concentration. Moreover, even when the test sample in which crystals precipitated was left at room temperature (22° C.) for one day, it was not confirmed that the precipitated crystals dissolved again. From the results of the above "Evaluation Tests 1 and 2", it is considered that both of the comparative compounds (x) and (y) have a rigid mother skeleton, which restricts molecular movement and facilitates stacking of molecules, and thus they are likely to crystallize. On the other hand, the compound of the present invention is less likely to stack due to the introduction of flexibility into the mother skeleton containing a linear alkylene group, which inhibits stacking of molecules, and as a result, crystallization is suppressed, and crystals do not precipitate even under low-temperature storage conditions such as 5°C or -5°C.

Claims

1. A substituted trisphenol compound, which is any of the compounds represented by the following chemical structural formulas: 【Chemistry 1】 【change】

2. A substituted trisphenol compound, which is any of the compounds represented by the following chemical structural formulas: 【Chemistry 2】 【change】

3. A substituted trisphenol compound, which is any of the compounds represented by the following chemical structural formulas: 【Chemistry 3】 【change】

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