Components for Resin Raw Materials

Abstract

The present invention addresses the problem of providing a starting-material composition for resins which makes it possible to produce a polyesterimide resin that has far higher mechanical properties than conventional ones. The starting-material composition for resins comprises a compound represented by formula (a) and a compound represented by formula (b), in a specific content ratio.

Description

Technical Field

[0001] The present invention relates to a composition for a resin raw material used for producing a resin having excellent mechanical properties.

Background Art

[0002] Polyimide has not only excellent heat resistance but also properties such as chemical resistance, radiation resistance, electrical insulation, and excellent mechanical properties. Therefore, it is widely used in various electronic devices such as substrates for flexible printed circuits (FPC), substrates for tape automated bonding (TAB), protective films for semiconductor elements, and interlayer insulating films for integrated circuits. In addition to these properties, polyimide has become increasingly important in recent years due to the simplicity of its manufacturing method, extremely high film purity, and ease of property improvement using various available monomers. The compound represented by the following formula (a), 2,2’,3,3’,5,5’-hexamethyl-biphenyl-4,4’-diol-bis(trimellitate anhydride) (hereinafter sometimes referred to as "Compound a") is a compound useful as a raw material for a polyesterimide resin having a high glass transition temperature, a low linear thermal expansion coefficient equivalent to that of a metal foil, an extremely low water absorption rate, a high elastic modulus, sufficient toughness, and sufficient adhesion to a metal foil (for example, Patent Documents 1 and 2).

Chemical Formula

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] When polyesterimide resin was manufactured using compound a as a raw material, the mechanical properties of the resulting resin sometimes varied significantly, even when the same manufacturing method was used. Therefore, there was a need for a resin raw material composition that could produce polyesterimide resin with stronger mechanical properties.

[0005] Conventionally, the impurities produced as by-products during the synthesis and purification processes of compound a, and the effects of these impurities on the resulting polyesterimide resin, have been completely unknown and have not been investigated. The present invention has been made against the above-mentioned background, and aims to provide a resin raw material composition that makes it possible to produce a polyesterimide resin with extremely superior mechanical properties compared to conventional materials. [Means for solving the problem]

[0006] As a result of diligent research to solve the above-mentioned problems, the inventors of the present invention discovered that certain impurities contained in 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol-bis(trimellitate anhydride) affect the mechanical properties of the resulting polyesterimide resin, and thus completed the present invention.

[0007] The present invention is as follows: 1. A resin raw material composition containing, as component A, a compound represented by the following formula (a), and as component B, a compound represented by the following formula (b), in the following composition ratio. [Composition Ratio]: Based on measurements by gel permeation chromatography using a differential refractometer as a detector, component A is at 99.0% to 99.99% of the total amount of all components detected, and component B is at 0.005% to 0.4% of the total amount of all components detected. [ka] [ka] (In the formula, R represents a hydrogen atom or R1-CO- (where R1 is an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms)). 2. A method for producing polyesterimide, comprising the steps of (i) reacting a composition containing a compound represented by the following formula (a) as component A and a compound represented by the following formula (b) as component B in the following composition ratio with a diamine to obtain a polyesterimide precursor, and then imidizing the precursor (ii). [Composition Ratio]: Based on measurements by gel permeation chromatography using a differential refractometer as a detector, component A is at 99.0% to 99.99% of the total amount of all components detected, and component B is at 0.005% to 0.4% of the total amount of all components detected. [ka] [ka] (In the formula, R represents a hydrogen atom or R1-CO- (where R1 is an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms)). [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a resin raw material composition that can produce polyesterimide resins with significantly superior mechanical properties compared to conventional materials. Furthermore, since it has been found that certain impurities affect mechanical properties, it is possible to produce polyesterimide resins with even tougher mechanical properties from a resin raw material composition in which these specific impurities have been reduced. [Modes for carrying out the invention]

[0009] The present invention will be described in detail below. <Ingredient A> The resin raw material composition of the present invention contains as component A the compound a "2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol-bis(trimellitate anhydride)" represented by the following formula (a). [Chemical formula]

[0010] In the composition for resin raw materials of the present invention, the content of component A is 99.0 area% or more and 99.99 area% or less with respect to the total amount of all components detected by measurement using gel permeation chromatography with a differential refractometer as a detector. The lower limit value is preferably 99.1 area% or more, more preferably 99.3 area% or more.

[0011] <Component B> The composition for resin raw materials of the present invention contains, as component B, a compound represented by the following formula (b) in the range of 0.005 area% or more and 0.4 area% or less with respect to the total amount of all components detected by measurement using gel permeation chromatography with a differential refractometer as a detector. The upper limit value is preferably 0.35 area% or less, more preferably 0.3 area% or less, still more preferably 0.2 area% or less, and particularly preferably 0.15 area% or less. Also, the lower limit value may preferably be 0.01 area% or more from the viewpoint of suppressing a decrease in the yield of component A, which is the target substance when repeatedly purifying. A polyesterimide resin obtained using a composition for resin raw materials containing more than 0.4 area% of the compound represented by the following formula (b) by the above measurement has significantly deteriorated mechanical properties. [Chemical formula] (In the formula, R represents a hydrogen atom or R1-CO- (where R1 is an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms)).

[0012] As a specific example of component B in the composition for resin raw materials of the present invention, for example, the following compound b1 in which "R" in the above formula (b) is a hydrogen atom can be mentioned. [Chemical formula] Compound b1 is a compound produced as a reaction intermediate when synthesizing compound a by the "acid halide method," which is one of the methods for producing the resin raw material composition of the present invention, as described later. The reaction equation for the production of compound b1 by the "acid halide method" is shown below. [ka]

[0013] Furthermore, as a specific example of component B in the resin raw material composition of the present invention, for example, the following compound b2 is given, in which "R" in the above formula (b) is R1-CO- and "R1" is an alkyl group having 1 carbon atom. [ka] The above compound b2 is one of the methods for producing the resin raw material composition of the present invention, as described later. This compound is produced as a reaction intermediate when synthesizing compound a using the "ster exchange method". The reaction equation for the formation of compound b2 by the "transesterification method" is shown below. [ka] Furthermore, in the aforementioned "acid halide method," compound b2 is treated with anhydrous vinegar in the post-reaction treatment step. When an acid is used, the resulting compound b1 is also a compound that is produced when it reacts with acetic anhydride. The reaction equation is shown below. [ka]

[0014] <Manufacturing Method 1: "Acid Halide Method"> The "acid halide method," which is one of the methods for producing the resin raw material composition of the present invention, will be described below. This "acid halide method" is a method for producing the resin raw material composition of the present invention, mainly composed of compound a, by reacting 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol with trimellitic anhydride halide, as shown in the reaction equation below. [ka]

[0015] Examples of trimellitic anhydride halides used in the above-mentioned "acid halide method" include trimellitic anhydride chloride (corresponding to the compound in the above reaction equation), trimellitic anhydride bromide, trimellitic anhydride iodide, and trimellitic anhydride fluoride. Among these trimellitic anhydride halides, trimellitic anhydride chloride is preferred because it is inexpensive and readily available. The amount of trimellitic anhydride halides used is typically 2 to 3 moles, preferably 2.1 to 2.5 moles, per mole of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol. In the above-described "acid halide method," hydrogen halides are generated by the reaction of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol with trimellitic anhydride halide, and a base is used to capture these halides. While not particularly limited, such bases can be used, including organic tertiary amines such as pyridine, triethylamine, and N,N-dimethylaniline, epoxy compounds such as propylene oxide, and inorganic bases such as potassium carbonate and sodium hydroxide. Among these, pyridine is preferred from the viewpoint of post-reaction separation, cost, and toxicity.

[0016] The above-described "acid halide method" initiates the reaction by mixing a solution of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol in the same solvent with trimellitic anhydride halide dissolved in a solvent. At this time, a base such as pyridine is included in the solution of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol that is being mixed. Conversely to the above mixing method, mixing a solution of trimellitic anhydride halide into a solution of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol is more likely to produce byproducts than the former method. Therefore, the former method, i.e., mixing a solution of trimellitic anhydride halide dissolved in a solvent with a solution of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol dissolved in the same solvent, is preferred. The molar ratio of the starting materials to the base used in the reaction is preferably within the range of 1.0 / 2.1~2.5 / 3.0~5.0 for 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol / trimellitic anhydride halide / base. The mixing of the above solutions should be carried out at low temperatures. The temperature in the reaction system is preferably in the range of -10 to 10°C, more preferably in the range of -5 to 7°C, and particularly preferably in the range of 0 to 5°C. There are no restrictions on the mixing time, but 2 to 4 hours is preferred.

[0017] The stirring immediately following the completion of mixing of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol and trimellitic anhydride halide (hereinafter sometimes referred to as "post-stirring 1") should continue under low temperature conditions, preferably within the range of -10 to 10°C, more preferably within the range of -5 to 7°C, and particularly preferably within the range of 0 to 5°C. "Post-stirring 1" should preferably be carried out within approximately 5 hours within this temperature range, and more preferably within 2 to 3 hours. After this "post-stirring 1," the reaction can be further accelerated by continuing stirring at a higher temperature than that of "post-stirring 1" (hereinafter sometimes referred to as "post-stirring 2") to complete the reaction. "Post-stirring 2" is preferably carried out at a temperature in the reaction system range of 50 to 75°C, more preferably in the range of 55 to 70°C, and particularly preferably in the range of 60 to 65°C. "Post-stirring 2" is preferably carried out within approximately 5 hours within this temperature range, and more preferably for 2 to 3 hours.

[0018] The solvents that can be used in the above-mentioned "acid halide method" are not particularly limited as long as they do not inhibit the reaction, but examples of aprotic solvents include tetrahydrofuran, 1,4-dioxane, picoline, pyridine, acetone, chloroform, toluene, xylene, dichloromethane, chloroform, 1,2-dichloroethane, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, hexamethylphosphoramide, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, 1,2-dimethoxyethane-bis(2-methoxyethyl) ether, and acetonitrile. These solvents may be used individually or in mixtures of two or more. Among these, tetrahydrofuran, γ-butyrolactone, γ-valerolactone, and acetonitrile are preferably used from the viewpoint of carrying out the reaction quickly and suppressing the residue of compound b1, which is a reaction intermediate.

[0019] <Manufacturing Method 2: "Transesterification"> The "transesterification method," which is one of the methods for producing the resin raw material composition of the present invention, will be described below. This "transesterification method" is a method for producing the resin raw material composition of the present invention, mainly composed of compound a, by reacting the dicarboxylic acid ester of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol with trimellitic anhydride, as shown in the reaction equation below. [ka] (In the formula, R1 represents an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms).

[0020] Examples of dicarboxylic acid esters of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol used in the above-mentioned "transesterification method" include, for example, 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol-bis(acetate), 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol-bis(propionate), 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol-bis(butyrate), 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol-bis(benzoate), and 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol-bis(naphthoate). These 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol dicarboxylic acid esters can be produced by conventionally known methods, such as reacting 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol with a carboxylic acid anhydride or carboxylic acid halide. In the above-described "transesterification method," the amount of trimellitic anhydride used is usually 2 molar times or more, preferably in the range of 2 to 10 molar times, and particularly preferably in the range of 2.6 to 3.4 molar times, relative to 1 mole of the dicarboxylic acid ester of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol. The reaction temperature for the above-mentioned "transesterification reaction" is typically in the range of 100 to 300°C, preferably in the range of 150 to 250°C, and particularly preferably in the range of 200 to 230°C.

[0021] In the above-mentioned "transesterification method," it is preferable to use a base as a catalyst in the reaction. Specifically, these bases can include, for example, inorganic alkali metal compounds such as alkali metal hydroxides, carbonates, and bicarbonate compounds, or organic alkali metal compounds such as alkali metal alcohols, phenols, and salts with organic carboxylic acids. Specifically, examples include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, lithium acetate, sodium acetate, and potassium acetate. The amount of these bases used is in the range of 0.001 to 10 mol%, preferably in the range of 0.005 to 5 mol%, per mole of the 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol dicarboxylic acid ester.

[0022] In the above-mentioned "transesterification method," it is preferable to use a reaction solvent during the reaction for reasons such as improved operability and reaction rate during industrial production. There are no particular restrictions on the solvents that can be used, as long as they do not distill out of the reaction vessel at the above reaction temperature and are inert to the transesterification reaction. Specifically, examples include aromatic hydrocarbon ether solvents such as alkylaryl ethers such as phenetol and butylphenyl ether, or diaryl ethers such as diphenyl ether and di-p-tolyl ether, aromatic hydrocarbon solvents such as biphenyl and terphenyl, alkyl-substituted naphthalenes such as diisopropylnaphthalene, aliphatic hydrocarbons such as decalin and kerosene, polyalkylene glycol ethers such as tetraethylene glycol dimethyl ether and diethylene glycol dibutyl ether, and organic solvents such as the SAM-S series (manufactured by Nippon Steel Chemical Co., Ltd.), KSK-OIL series (manufactured by Soken Chemical Co., Ltd.), or Neo SK-OIL series (manufactured by Soken Chemical Co., Ltd.). When using these solvents, the amount used is usually in the range of 1 to 10 parts by weight, preferably 2 to 3 parts by weight, per 1 part by weight of the 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol dicarboxylic acid ester.

[0023] <Purification> The resin raw material composition of the present invention can usually be obtained by purifying the reaction product obtained by the above-described reaction in order to set the content of the compound represented by formula (b) as component B within a specific range. While known methods can be used for purification, it is preferable to use crystallization and reslurrying (suspending a solid in a solvent). To obtain a specific amount of component B, it is more preferable to repeat these operations multiple times rather than just once. There are no particular restrictions on the solvent that can be used for crystallization and reslurrying, as long as it is inert with component A, but specific examples include acetic anhydride, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, tetrahydrofuran, methyl isobutyl ether, methyl isopropyl ether, toluene, xylene, ethylbenzene, γ-butyrolactone, γ-valerolactone, acetonitrile, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. Among these, acetic anhydride, cyclohexanone, and γ-butyrolactone are preferred. The crystallization conditions vary depending on the solvent used and cannot be generalized, but for example, when using γ-butyrolactone, the amount of solvent used is in the range of 5 to 50 parts by weight, more preferably 10 to 30 parts by weight, and particularly preferably 1 to 20 parts by weight, per 1 part by weight of the total amount of the composition containing component A, component B and other impurities to be purified. The dissolution temperature is in the range of 100 to 200°C, more preferably 110 to 180°C, even more preferably 110 to 160°C, and particularly preferably 120 to 140°C. The cooling temperature is in the range of 0 to 50°C, more preferably 10 to 40°C, and even more preferably 15 to 30°C. The conditions for the reslurry method vary depending on the solvent used and cannot be generalized, but for example, when using γ-butyrolactone, the amount of solvent used is preferably in the range of 2 to 20 parts by weight, more preferably in the range of 2 to 12 parts by weight, and even more preferably in the range of 4 to 8 parts by weight, per 1 part by weight of the total amount of the composition containing component A, component B and other impurities to be purified. The processing temperature is preferably in the range of 100 to 200°C, more preferably in the range of 110 to 180°C, even more preferably in the range of 110 to 160°C, and particularly preferably in the range of 120 to 140°C. The reslurry treatment is preferably carried out for about 0.5 to 3 hours. When using other solvents, various conditions can be appropriately modified, taking into account the boiling point of the solvent, the components A and B to be purified, other impurities, and the solubility of the composition containing them. Furthermore, before crystallization by purification operations such as crystallization and reslurrying, a high-purity product can be obtained by filtering the solution containing components A and B and other impurities to separate the inorganic salts, or by washing with water. In this case, even if some or all of the acid anhydride groups of components A and B open up to form carboxylic acids upon contact with water, they can be returned to carboxylic acid anhydrides by heat treatment or reaction with acid anhydrides such as acetic anhydride. Since the purified product obtained through these purification steps may contain the solvent used, it is preferable to remove the solvent and dry the product. The method for removing the solvent is not particularly limited, but one example is to heat the product under atmospheric pressure or reduced pressure and distill off the solvent.

[0024] <Polyesterimide obtained using the resin raw material composition of the present invention> Polyesterimide can be produced by (i) reacting the resin raw material composition of the present invention with a diamine to obtain a polyesterimide precursor (polyamic acid), and then imidizing it (ii).

[0025] <(i) Step to obtain a polyesterimide precursor (polyamic acid)> The step of obtaining a polyesterimide precursor involves reacting the resin raw material composition of the present invention with a diamine. Specifically, for example, in a reaction vessel, the diamine is first dissolved in a polymerization solvent, and the resin raw material composition of the present invention, which is substantially equimolar to the diamine, is gradually added to this solution to carry out the reaction. The temperature at this time is in the range of 0 to 100°C, preferably in the range of 5 to 80°C, more preferably in the range of 10 to 60°C, even more preferably in the range of 15 to 40°C, and particularly preferably in the range of 20 to 30°C. In this process, the monomer concentration is typically in the range of 5 to 50% by weight. By carrying out polymerization within this monomer concentration range, a uniform polyesterimide precursor with a high degree of polymerization can be obtained. If the degree of polymerization of the polyesterimide precursor increases too much and the polymerization solution becomes difficult to stir, it can be diluted with the same solvent as appropriate. There are no particular restrictions on the types of diamines that can be used, but aromatic diamines and aliphatic diamines can be used. Examples of aromatic diamines include p-phenylenediamine, 3,4'-diaminodiphenyl ether, 4-aminophenyl-4'-aminobenzoate, benzidine, 3,3'-dihydroxybenzidine, 2,2'-bis(trifluoromethyl)benzidine (TFMB), 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, and 2,2-bis(4-aminophenyl)fluorene, with 2,2'-bis(trifluoromethyl)benzidine (TFMB) being particularly preferred. Examples of aliphatic diamines include, for example, 4,4'-methylenebis(cyclohexylamine), 1,4-cyclohexanebis(methylamine), 2,2-bis(4-aminocyclohexyl)propane, 2,2-bis(4-aminocyclohexyl)hexafluoropropane, trans-1,4-diaminocyclohexane, 1,4-tetramethylenediamine, 1,5-pentamethylenediamine, and 1,6-hexamethylenediamine. Any polymerization solvent can be used as long as it dissolves the raw material monomers, the resulting polyesterimide precursor, and the imidized polyesterimide without interfering with the reaction. Examples of suitable solvents include amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone; cyclic ester solvents such as γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, and α-methyl-γ-butyrolactone; carbonate solvents such as ethylene carbonate and propylene carbonate; glycol solvents such as triethylene glycol; phenolic solvents such as m-cresol, p-cresol, 3-chlorophenol, and 4-chlorophenol; acetophenone, 1,3-dimethyl-2-imidazolidinone, sulfolane, and dimethyl sulfoxide. Of these, aprotic solvents such as amide solvents, cyclic ester solvents, and carbonate solvents are preferred, specifically N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and dimethyl sulfoxide are preferred. Furthermore, it is preferable to use these solvents that have been dehydrated beforehand. When polymerizing the polyesterimide precursor, aromatic or aliphatic tetracarboxylic dianhydrides other than the resin raw material composition of the present invention, which is a tetracarboxylic dianhydride, can be used in combination as copolymerization components. By using the resin raw material composition of the present invention, a polyesterimide precursor with a higher intrinsic viscosity can be obtained compared to when using conventional raw materials.

[0026] (ii) Step of imidizing the polyester imide precursor Next, we will describe the process of imidizing the obtained polyesterimide precursor in order to obtain polyesterimide. For imidizing the polyester imide precursor, known methods such as thermal imidization, which involves thermal dehydration and ring closure, and chemical imidization, which uses a dehydrating agent, can be used. Of these, chemical imidization, which does not require high-temperature heat treatment and can be performed under mild conditions, is preferred. In the thermal imidation method, for example, imidation can be carried out by mixing an azeotrope with water, such as toluene or xylene, into the reaction solution used in the process of obtaining the polyester imide precursor described above, and heating the mixture to remove the by-product water from the system. The reaction temperature should be above the temperature at which water is distilled out of the system, for example, above the azeotropic point or above 100°C, more preferably above 120°C, and even more preferably above 130°C. Heating above 150°C is undesirable because the solvent may become discolored, and this discoloration may cause discoloration of the film. Alternatively, the polymerized polyester imide precursor solution can be cast onto a substrate such as glass and dried to form a precursor film. Then, the substrate can be heated at atmospheric pressure or in a vacuum in the range of 200 to 400°C to carry out imidation. In the chemical imidation method, for example, the aforementioned polyester imide precursor solution is adjusted to a suitable viscosity that facilitates stirring using the same solvent used during polymerization. While stirring with a stirrer, a dehydrating ring-closing agent (chemical imidizing agent) consisting of an organic acid anhydride and a basic catalyst is mixed in to carry out the imidation reaction. The temperature at this time is in the range of 0 to 100°C, preferably in the range of 5 to 80°C, more preferably in the range of 10 to 60°C, even more preferably in the range of 15 to 40°C, and particularly preferably in the range of 20 to 30°C. The organic acid anhydrides that can be used in this process are not particularly limited, but examples include acetic anhydride and propionic anhydride. Acetic anhydride is preferably used due to its ease of handling and purification as a reagent. Furthermore, while there are no particular limitations on the basic catalyst, pyridine, triethylamine, quinoline, etc., can be used, pyridine is preferred due to its ease of handling and separation of the reagent. The amount of organic acid anhydride in the chemical imidizing agent is in the range of 1 to 10 times the theoretical dehydration amount of the polyesterimide precursor. The amount of basic catalyst is in the range of 0.1 to 2 times the amount of organic acid anhydride. The reaction solution after chemical imidation contains by-products such as chemical imidizing agents and carboxylic acids, so it is necessary to remove these and purify the polyesterimide. Known methods can be used for purification. For example, the simplest method is to drop the imidized reaction solution into a large amount of poor solvent (e.g., alcoholic solvents such as methanol and ethanol, or aliphatic hydrocarbon solvents such as hexane) while stirring to precipitate the polyesterimide, and then recover the polyesterimide powder. If the solid content concentration of the polyimide in the reaction solution dropped into the poor solvent is too high, the precipitated polyimide will form granular clumps, impurities may remain in these coarse particles, and it may take a long time to redissolve the obtained polyimide powder in the solvent. On the other hand, if the concentration is too low, a large amount of poor solvent will be required, which may increase the environmental burden due to waste solvent treatment and increase manufacturing costs. Therefore, a solvent such as the polymerization solvent may be added to the liquid after the polyesterimide has precipitated. Then, if necessary, the powder can be repeatedly washed until the by-products are removed, and the powder with the solvent attached can be dried under reduced pressure to obtain polyesterimide powder. By applying the polyester imide manufacturing method of the present invention, it is possible to obtain a polyester imide with a higher intrinsic viscosity compared to that obtained using conventional raw materials. Furthermore, it is possible to obtain a polyester imide in which the breaking strength, mean elongation at break, and maximum elongation in tensile strength tests when it is made into a film are all significantly improved.

[0027] <Manufacturing of Polyesterimide Solution> The resulting polyesterimide can be dissolved in an organic solvent to form a solution. The organic solvent can be appropriately selected according to the intended use of the solution and processing conditions. When coating continuously for a long period of time, the organic solvent in the polyesterimide solution may absorb moisture from the atmosphere, potentially causing the polyesterimide to precipitate. Therefore, it is preferable to use a low-hygroscopic solvent such as triethylene glycol dimethyl ether, γ-butyrolactone, or cyclopentanone. The solid content concentration can be appropriately selected depending on the application of the solution, and there are no particular restrictions. For example, when forming a film, although it depends on the molecular weight of the polyesterimide, the manufacturing method, and the thickness of the film to be manufactured, it is preferable to have a solid content concentration of 5% by weight or more.

[0028] <Manufacturing of polyester imide film> The obtained polyesterimide solution can be used to form a polyesterimide film. Known methods can be used for its production; for example, a polyesterimide film can be produced by applying the polyesterimide solution onto a support such as a glass substrate using a doctor blade, and then drying it. Furthermore, to remove residual strain, heat treatment can be performed in an inert gas atmosphere or vacuum at a temperature in the range of 150 to 300°C. [Examples]

[0029] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. 1. Gel permeation chromatography Equipment: Tosoh Corporation high-speed GPC system HLC-8320GPC Columns: TSKgel Guardcolum HXL-L (1 tube), TSKgel G2000HXL (2 tubes), TSKgel G3000HXL (1 tube), TSKgel G400 Flow rate: Pump Sam. 1.0 ml / min, Ref. Sam. 1 / 3 Mobile phase: tetrahydrofuran Column temperature: constant 40°C Detector: Differential refractometer (RI) An RI detector detects the difference in refractive index between the sample solution and the reference eluent, and the refractive index of the solution correlates with the weight concentration of the solution. Sample concentration: 30 mg / 50 ml (tetrahydrofuran solution) Injection volume: 100μl 2. Time-of-flight mass spectrometry (TOF-MS analysis) Equipment: Bruker MicroTOFSII TOF-MS system Ion source: APCI / Direct probe Target ion species: cation

[0030] 3.Intrinsic viscosity The reducing viscosity of a 0.5 wt% polyimide precursor solution and a polyimide solution was measured at 30°C using an Ostwald viscometer (SIBATA 026300-1, inner diameter approximately 0.5 mm, manufactured by Shibata Scientific Co., Ltd.). This value was considered to be the intrinsic viscosity. 4. Breaking strength, breaking elongation Tensile tests (test speed: 100 mm / min) were performed on polyimide film test specimens (JIS K6251 dumbbell-shaped type 6) using a universal material testing machine Model 5569 and a load cell: 100N (manufactured by Instro Japan Company Limited). The breaking strength (MPa) and the elongation at break (%) were determined from the elongation at which the film broke (5 tests). A higher elongation rate at break indicates higher toughness of the film. The breaking strength was determined from the stress at the time of breakage.

[0031] <Synthesis Example 1> To prepare the resin raw material compositions for Comparative Examples 1 and 2 below, resin raw material compositions were manufactured. The detailed procedure is as follows. 53.0 g (0.25 mol) of trimellitic acid chloride anhydride and 197.4 g of tetrahydrofuran were charged into a four-necked flask equipped with a thermometer, stirrer, and condenser. The mixture was dissolved by stirring while the container was purged with nitrogen and cooled to below 5°C. Subsequently, a preparation containing 40.0 g (0.15 mol) of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol, 250.0 g of tetrahydrofuran, and 23.4 g (0.30 mol) of pyridine was added dropwise at a constant rate over 2 hours while maintaining the flask temperature below 5°C. After the addition was complete, the mixture was stirred at 2-8°C for 24 hours. Then, water was added at room temperature, stirred for 2 hours, and the internal temperature was raised to 40°C for 6 hours. After that, the mixture was cooled to below 10°C and a large amount of water was added, resulting in the formation of a white precipitate. The white precipitate was then filtered off and vacuum-dried at 60°C to obtain 62.5 g of the product. Subsequently, the obtained product and acetic anhydride were charged into a four-necked flask and reacted at 100°C for 2 hours. After stirring for 24 hours while cooling to room temperature, a white precipitate was formed. The precipitate was filtered off and washed with γ-butyrolactone. Then, it was dried under reduced pressure at 120°C for 1 hour and then at 150°C for 1 hour. Furthermore, the obtained precipitate was washed with γ-butyrolactone by holding at 100°C for 1 hour, cooled, filtered off, and dried under reduced pressure at 150°C for 2 hours. The white solid obtained in this manner was subjected to gel permeation chromatography (GPC) RI analysis and TOF-MS analysis, respectively. As a result, the obtained resin raw material composition contained 87.7 area% of compound a as component A of the present invention, and 10.4 area% of the sum of compounds b1 and b2 as component B of the present invention. Furthermore, TOF-MS analysis detected the molecular weight of compound b1 at Exact Mass (E / Z=444) and the molecular weight of compound b2 at Exact Mass (E / Z=486), confirming that these compounds have the chemical structural formulas (b1) and (b2) shown in the following chemical formulas. [ka]

[0032] <Example 1> The resin raw material composition of the present invention was manufactured. The detailed procedure is as follows. In a four-necked flask equipped with a thermometer, stirrer, and condenser, 411.8 g (1.96 mol) of trimellitic chloride anhydride and 1213.0 g of tetrahydrofuran were charged. The mixture was dissolved by stirring while the container was purged with nitrogen and cooled to below 5°C. Subsequently, a preparation containing 229.8 g (0.85 mol) of 2,2',3,3',5,5'-hexamethyl-biphenyl-4,4'-diol, 1545.0 g of tetrahydrofuran, and 336.2 g (4.25 mol) was added dropwise at a constant rate over 2 hours while maintaining the flask temperature below 5°C. After the addition was complete, the mixture was stirred at below 5°C for 2 hours (post-stirring 1). Then, the temperature was raised to 65°C and stirred for 3 hours (post-stirring 2). After the reaction was complete, the mixture was cooled to 40°C with stirring, 200.0 g of water was added, and the mixture was maintained at 40°C for 14 hours. The mixture was then cooled to 25°C, and the resulting precipitate was filtered off. Next, the product and acetic anhydride were placed in a four-necked flask and maintained at 100°C for 2 hours. After cooling to 25°C, the resulting precipitate was filtered off. The filtered precipitate was further washed with γ-butyrolactone at 120°C to form a slurry, and then filtered at 25°C. The filtered precipitate was further washed with cyclohexanone at 100°C to form a slurry, and then filtered at 25°C. The filtered precipitate was then heated to 100°C under reduced pressure and dried. The white solid obtained in this manner was subjected to gel permeation chromatography (GPC) RI analysis. As a result, it was revealed that the resin raw material composition of the present invention contains 99.4 area percent of compound a as component A and 0.1 area percent of the sum of compounds b1 and b2 as component B of the present invention.

[0033] (Polymide precursor polymerization) 1.284 g (4.01 mmol) of 2,2'-bis(trifluoromethyl)benzidine (TFMB) was dissolved in 33.784 g of anhydrous N,N'-dimethylacetamide (DMAc). 2.469 g (3.97 mmol) of the resin raw material composition from Example 1 was slowly added to this solution, and the mixture was stirred at room temperature for 72 hours to obtain polyamic acid, a polyimide precursor (solid content concentration 10.0 wt%). The intrinsic viscosity of the obtained polyamic acid was 5.01 dL / g.

[0034] (Chemical imidation reaction) The obtained polyamic acid was diluted with dehydrated dimethylacetamide to a solid content concentration of 6.5% by weight. A mixed solution of 24.69 mmol of acetic anhydride and 12.35 mmol of pyridine was slowly added dropwise at room temperature while stirring, and stirring was continued for another 24 hours after the addition was complete. The obtained polyimide solution was slowly added dropwise to a large amount of methanol. Dimethylacetamide was then added to precipitate the fibrous polyimide, which was then filtered off. The resulting white precipitate was washed with methanol and dried under vacuum at 60°C.

[0035] (Preparation of polyimide solution and formation of polyimide film) The above polyimide powder was redissolved in cyclopentanone at room temperature to prepare a 5.1% by weight homogeneous solution. This polyimide solution was cast onto a glass substrate and dried in a hot air dryer at 60°C for 2 hours. Then, the substrate and film were heat-treated in a vacuum at 250°C for 1 hour and allowed to cool to room temperature before the film was peeled off the glass substrate. The polyimide film was heat-treated again in a vacuum at 250°C for 10 minutes to remove residual strain. The resulting polyimide film was almost colorless and transparent. The mechanical properties of this polyimide film (thickness 20 μm) were measured. The results are shown in Table 1 below.

[0036] <Example 2> To evaluate the effect of the content of component B, the resin raw material composition of the present invention obtained in Example 1 and the resin raw material composition obtained in Synthesis Example 1 were mixed by weight so that the content of component B was 0.3 area% (at this time, compound a was 99.3 area%). Polymerization of the polyimide precursor was carried out in the same manner as in Example 1, and the intrinsic viscosity at 52 hours was 4.39 dL / g, and the intrinsic viscosity at 72 hours was 4.46 dL / g. Subsequently, the chemical imidation reaction and polyimide film preparation were carried out in the same manner as in Example 1, and the mechanical properties were measured. The results are shown in Table 1 below.

[0037] <Comparative Example 1> A composition was prepared by mixing the components by weight so that the content of component B was 1.0 area%, in the same manner as in Example 2 (at this time, compound a was 98.4 area%). Polymerization of the polyimide precursor was carried out in the same manner as in Example 1, and the intrinsic viscosity at 52 hours was 3.29 dL / g, and the intrinsic viscosity at 72 hours was 3.30 dL / g. Subsequently, the chemical imidation reaction and polyimide film preparation were carried out in the same manner as in Example 1, and the mechanical properties were measured. The results are shown in Table 1 below.

[0038] <Comparative Example 2> A composition was prepared by mixing the compounds in the same manner as in Example 2, so that the content of component B was 0.5 area% (at this time, compound A was 98.9 area%). Polymerization of the polyimide precursor was carried out in the same manner as in Example 1, and the intrinsic viscosity at 52 hours was 4.24 dL / g, and the intrinsic viscosity at 72 hours was 4.26 dL / g. Subsequently, a chemical imidation reaction and a polyimide film were prepared in the same manner as in Example 1, and the mechanical properties were measured. The results are shown in Table 1 below.

[0039] <Comparative Example 3> The manufacturing method described in "Synthesis Example 1" of the above-mentioned Patent Document 2 was replicated, and gel permeation chromatography (GPC) RI analysis was performed on the recrystallized product obtained after the "purification" step. As a result, the composition contained 96.4 area% of compound a as component A of the present invention, and 1.8 area% of the total of compounds b1 and b2 as component B of the present invention. Furthermore, the chemical structures of compounds b1 and b2 were confirmed in the same manner as in Example 1. The "intrinsic viscosity of polyamic acid," "intrinsic viscosity of polyimide acid," and the mechanical properties of the polyimide film described in "Example 1" (paragraphs 0065-0067) of Patent Document 2 above are transcribed in Table 1 below, marked with the symbol "*". These mechanical properties cannot be directly compared to Examples 1 and 2, Comparative Examples 1 and 2, or Comparative Examples 1 and 2, due to differences in film thickness and test conditions, but they are included as reference values.

[0040] [Table 1]

[0041] The results in Table 1 show that when the resin raw material compositions of Examples 1 and 2, which contain specific amounts of components A and B of the present invention, are used, the intrinsic viscosity of the resulting polyamic acid and polyimide increases compared to the resin raw material compositions of Comparative Examples 1 to 3, which have a low content of the main component A and a high content of the impurity component B. Furthermore, the average breaking strength, maximum breaking strength, average breaking elongation, and maximum breaking elongation in the tensile strength test results of the resulting polyimide film are all significantly improved.

Claims

1. A resin raw material composition containing, as component A, a compound represented by the following formula (a), and as component B, compounds represented by the following formulas (b1) and (b2), in the following composition ratios. [Composition Ratio]: Based on measurements by gel permeation chromatography using a differential refractometer as a detector, component A is 99.3% to 99.99% of the total amount of all components detected, and component B is 0.005% to 0.3% of the total amount of all components detected. 【Chemistry 1】 【Chemistry 2】 【Transformation 3】

2. A method for producing polyester imide, comprising the steps of: (i) reacting a composition containing a compound represented by the following formula (a) as component A and compounds represented by the following formulas (b1) and (b2) as component B in the following composition ratios with a diamine to obtain a polyester imide precursor; and (ii) imidizing the same. [Composition Ratio]: Based on measurements by gel permeation chromatography using a differential refractometer as a detector, component A is 99.3% to 99.99% of the total amount of all components detected, and component B is 0.005% to 0.3% of the total amount of all components detected. 【Chemistry 4】 【Transformation 5】 【Transformation 6】

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