JP3496845B2 - Resin manufacturing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a resin. [0002] The following method is generally known as a method for subjecting a phenol and / or naphthol to a hydroxybenzaldehyde condensation reaction and extracting the resulting resin as crystals. For example, phenols and / or naphthols are reacted with hydroxybenzaldehydes in an organic solvent using an acid catalyst, and water produced is distilled off azeotropically from the system, leaving only the organic solvent in the system. The resin can be obtained by the method of returning to the above. As a method for isolating the obtained resin as crystals, a method is known in which a poor solvent such as n-hexane is added to a reaction solution to crystallize the resin, and the crystal is filtered and dried. [0004] The resin obtained by such a method is brown or reddish-brown. After the resin is taken out of the reaction vessel, the reaction vessel is colored, and the cleaning thereof is troublesome. There was such a problem. JP-A-6-234831 discloses a method for improving the hue of the obtained resin by adding an organic antioxidant or an inorganic reducing agent during the condensation reaction. However, when an organic antioxidant is added, it is difficult to remove the additive after the reaction, and the purity of the target product may be reduced. Further, when an inorganic reducing agent is added during the condensation reaction, the reducing agent may be decomposed by being exposed to a high temperature under acidic conditions to generate toxic substances.
In order to solve the above-mentioned problems, there is a long-awaited need for a method for producing a resin that can safely prevent coloring of the resin and that does not leave any additives in the obtained resin. In view of these circumstances, the present inventors have sought a method for suppressing the coloration of a resin obtained by a condensation reaction of phenols and / or naphthols with hydroxybenzaldehydes. As a result of intensive studies, the present invention has been completed. That is, according to the present invention, a phenol and / or naphthol is condensed with a hydroxybenzaldehyde in an organic solvent in the presence of an acid catalyst, and then water is added to the reaction mixture, followed by alkali metal hydroxide. Alternatively, an alkali metal carbonate is added at a specific ratio, the resulting resin is dispersed in water, and after the organic solvent is distilled out of the reaction system by azeotropic distillation, an acid is added dropwise to crystallize the reaction product. In a method for producing a resin, before or after the organic solvent is distilled out of the system by azeotropic distillation, a reducing agent is added, and then an acid is added dropwise to crystallize the reaction product, which is characterized by the following formula ( Method for producing resin represented by 1) (In the formula (1), each R independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms,
n represents an integer. ). Hereinafter, the present invention will be described in detail. ADVANTAGE OF THE INVENTION According to the manufacturing method of this invention, coloring of the resin obtained by condensation reaction of phenols and / or naphthols and hydroxybenzaldehydes can be suppressed significantly. Specific examples of the phenols used in the present invention include phenol, cresol, xylenol, trimethylphenol, propylphenol, butylphenol, methylbutylphenol and phenylphenol. Specific examples of the naphthols include α-naphthol. , Β-naphthol and the like, and specific examples of hydroxybenzaldehydes include parahydroxybenzaldehyde and salicylaldehyde.
It is not limited to these. In addition, phenols, naphthols, hydroxybenzaldehydes,
One of the compounds selected from the groups exemplified above.
Types may be used, or various types may be used in combination. The charging ratio of phenols or naphthols to hydroxybenzaldehydes is preferably from 1.3 to 10 moles, more preferably from 1.5 to 8 moles of phenols or naphthols per mole of hydroxybenzaldehyde. Although the condensation reaction can be carried out without using any solvent, it is preferable to carry out the reaction in an organic solvent. Examples of the organic solvent that can be used include toluene, xylene, and chlorobenzene, and toluene is particularly preferable. The amount of the organic solvent used is preferably 20 to 300% by weight, more preferably 40 to 150% by weight of the total weight of the charged phenols or naphthols and hydroxybenzaldehydes. When performing the condensation reaction, it is preferable to use an acid catalyst. Specific examples of the acid catalyst that can be used include p-toluenesulfonic acid, oxalic acid, and hydrochloric acid.
The amount of the acid catalyst used is preferably 0.001 to 0.05 mol per 1 mol of the charged hydroxybenzaldehyde,
Particularly, 0.002 to 0.02 mol is preferable. The condensation reaction is preferably carried out at a temperature at which the organic solvent is refluxed. Water is generated with the progress of the condensation reaction. The generated water and the organic solvent are distilled off and separated by azeotropic distillation, the organic solvent is returned to the system, and the water in the reaction system is removed. The reaction time is preferably 1 to 15 hours, particularly preferably 2 to 10 hours. After completion of the reaction, the temperature of the reaction mixture is lowered to 80 ° C. or lower, and water is added. The amount of water is 1 to 6 times, preferably 2 to 5 times the total weight of the total weight of phenols and / or naphthols and hydroxybenzaldehydes. Next, an alkali metal hydroxide or an alkali metal carbonate is added to convert all or a part of the phenolic hydroxyl groups of the resin formed above into an alkali metal salt, thereby increasing the hydrophilicity of the resin and thereby bringing the resin into water. Disperse. Specific examples of the alkali metal hydroxide that can be used include sodium hydroxide, potassium hydroxide, and the like. Specific examples of the alkali metal carbonate include sodium carbonate, potassium carbonate, and the like. preferable. The amount of the alkali metal hydroxide to be added may be an amount sufficient to disperse the formed resin in water, and is usually 0.002 to the equivalent number of phenolic hydroxyl groups of the resin.
It is 1.0 equivalent, preferably 0.005 to 0.8 equivalent. The alkali metal hydroxide or alkali metal carbonate may be added as a solid or in the form of an aqueous solution, but an aqueous solution is preferred. When added as an aqueous solution, the concentration is preferably 10 to 50% by weight, particularly preferably 15 to 45% by weight. Next, after dispersing the formed resin in water, the temperature is increased, and the organic solvent is distilled out of the reaction system by azeotropic distillation with water. Alternatively, or later, a reducing agent is added. Specific examples of the reducing agent that can be used here are hypophosphorous acid, phosphorous acid, thiosulfuric acid, sulfurous acid, oxalic acid, formic acid, hydrosulfite or salts thereof. The type of salt is not particularly limited. These reducing agents can be used alone or in combination. The amount of the reducing agent used is 0.01 to 20 parts by weight based on 100 parts by weight of phenols and / or naphthols.
Part by weight is preferable, and 0.1 to 15 parts by weight is particularly preferable. After the organic solvent has been completely distilled off, an acid is added dropwise and neutralization precipitates resin crystals. The organic solvent thus recovered can be reused for the next condensation reaction. The temperature during the neutralization reaction is 20 to 80 ° C, especially 30 to 80 ° C.
70 ° C. is preferred. Specific examples of the acid that can be used here include sulfuric acid, hydrochloric acid, and acetic acid. The amount and method of addition of the acid are such that an acid equivalent to the previously added alkali metal hydroxide or alkali metal carbonate is added dropwise over 5 to 30 minutes. Next, filtration and drying are performed to obtain a desired resin. The resin obtained by the production method of the present invention is extremely useful as a developer for a thermal dye, an antioxidant, a photoresist, a raw material for an epoxy resin, and the like. EXAMPLES Next, the present invention will be described in more detail with reference to Examples. In the following, parts are by weight unless otherwise specified. Example 1 A round bottom flask equipped with a stirrer, a condenser, a fractionating tube and a thermometer was charged with 61 parts of parahydroxybenzaldehyde,
3-methyl-6-tert-butylphenol 156
Parts, toluene 152 parts, p-toluenesulfonic acid 0.6
After stirring and dissolving the parts, the product water and toluene were distilled off under reflux, the liquid was further separated, the water was removed, and the reaction was carried out for 4 hours while returning the toluene into the reaction system. After the completion of the reaction, the temperature of the reaction mixture was lowered to 70 ° C., 600 parts of water was added with stirring, and 20 parts of a 25% by weight aqueous sodium hydroxide solution was further added to disperse the product in water. Then sodium hydrosulfite 4
Then, the temperature of the reaction mixture was raised to 100 ° C., and 151 parts of toluene and 60 parts of water were distilled out of the reaction system by azeotropic distillation. Further, the temperature of the reaction mixture was lowered to 50 ° C.
Under stirring, 8.2 parts of 75% sulfuric acid was added dropwise over 10 minutes to neutralize and crystallize. The resulting aqueous dispersion of the resin crystals was subjected to suction filtration, and further washed with 400 parts of water.
And dried with hot air for 24 hours to obtain 205 parts of a resin (A) represented by the formula (2). Embedded image (In the formula (2), n represents an integer.) Example 2 The same procedure as in Example 1 was carried out except that the amount of sodium hydrosulfite was changed to 2 parts. As a result, 204 parts of a resin (B) represented by the above formula (2) was obtained. Example 3 The procedure of Example 1 was repeated, except that 4 parts of sodium hydrosulfite was added immediately after the toluene was distilled off by azeotropic distillation. The obtained resin (C) 205 parts was obtained. Comparative Example 1 A resin (D) was prepared in the same manner as in Example 1 except that sodium hydrosulfite was not added.
205 parts were obtained. Test Example 1 0.5 parts of each of the obtained resins (A) to (D) was dissolved in 50 ml of acetone, and the Gardner color number or the Hazen color number (JIS K-6901-4, 2, 1) was dissolved. ), The hue was measured. Table 1 shows the results. Table 1 Table 1 Gardner color number Hazen color number Resin (A) * 250 Resin (B) * 500 Resin (C) 7 * Resin (D) 9 * The Gardner color number is Hazen color. Since it is used for the measurement of the hue darker than the number, the portion where the corresponding measurement was not performed in Table 1 is indicated by *. Example 4 A round bottom flask equipped with a stirrer, a condenser, a fractionating tube, and a thermometer was charged with 61 parts of parahydroxybenzaldehyde.
After 136.8 parts of β-naphthol, 138 parts of toluene and 0.6 part of paratoluenesulfonic acid were charged and dissolved by stirring,
Under reflux, the produced water and toluene were distilled off, liquids were further separated, water was removed, and the reaction was carried out for 6 hours while returning toluene into the reaction system. After completion of the reaction, the temperature of the reaction mixture was lowered to 70 ° C., 560 parts of water was added with stirring, and 20 parts of a 25% by weight aqueous sodium hydroxide solution was added to disperse the product in water. Then sodium hydrosulfite 4
After the addition of parts, the temperature of the reaction mixture was raised to 100 ° C., and 136 parts of toluene and 50 parts of water were distilled out of the reaction system by azeotropic distillation. The temperature of the reaction mixture was further reduced to 50 ° C.
Under stirring, 8.2 parts of 75% sulfuric acid was added dropwise over 10 minutes to neutralize and crystallize. The obtained aqueous dispersion of the resin crystals was subjected to suction filtration, and further washed with 380 parts of water.
And dried with hot air for 24 hours to obtain 183 parts of a resin (E) represented by the formula (3). Embedded image (In the formula (3), n represents an integer.) Example 5 The same treatment as in Example 4 was carried out except that the amount of sodium hydrosulfite was changed to 2 parts. As a result, 182 parts of a resin (F) represented by the above formula (3) was obtained. Example 6 The procedure of Example 4 was repeated, except that the addition of 4 parts of sodium hydrosulfite was immediately after the toluene was removed by azeotropic distillation. 183 parts of resin (G) represented by 3) was obtained. Comparative Example 2 Resin (H) 1 was prepared in the same manner as in Example 4 except that sodium hydrosulfite was not added.
82 parts were obtained. Test Example 2 0.5 parts of each of the obtained resins (E) to (H) was dissolved in 50 ml of acetone, and the Gardner color number or the Hazen color number (JIS K-6901-4, 2, 1) was dissolved. ), The hue was measured. Table 2 shows the results. Table 2 Table 2 Gardner color number Hazen color number Resin (E) * 500 Resin (F) 1 * Resin (G) 9 * Resin (H) 11 * As described above, the resin obtained by the production method of the present invention is a resin with little coloring. According to the resin production method of the present invention, the hue of the resin is greatly improved. Further, since the reducing agent is not used under acidic conditions, there is no generation of toxic substances and the like, and there is no possibility that the reducing agent remains due to filtration and washing with an aqueous system.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-133334 (JP, A) JP-A-6-234831 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 8/00-8/38

Claims (1)

(57) Claims 1. A phenol and / or naphthol is condensed with hydroxybenzaldehyde in an organic solvent in the presence of an acid catalyst, and then water is added to the reaction mixture.
Next , the equivalent number of phenolic hydroxyl groups of the resin that produced the alkali metal hydroxide or alkali metal carbonate was 0.0
After adding an equivalent of 02 to 1.0 times to disperse the produced resin in water and further distilling the organic solvent out of the reaction system by azeotropic distillation, the acid is added dropwise to produce a resin which crystallizes the reaction product. In the method, a reducing agent is added before or after the organic solvent is distilled out of the system by azeotropy, and then an acid is added dropwise to crystallize the reaction product. The method for producing the represented resin. Embedded image (In the formula (1), R independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms, and n represents an integer.)