JPH11199658A - Production of phenolic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily produce a phenolic resin having excellent color tone by a small number of processes. SOLUTION: These processes comprise (I) the process in which an unsaturated hydrocarbon is made to react with an excess amount of a phenol in the presence of a boron trifluoride catalyst substantially without using a solvent, (II) the process in which the catalyst present in the reaction mixture is deactivated by using an ion exchanger, (III) the process in which the reaction mixture is bleached by adding an inorganic porous substance and stirring the mixture without removing the unreacted phenol and (IV) the process in which solid substances and the unreacted phenol are each removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simple method for producing a hydrocarbon-phenol resin which is optimal as a raw material for a semiconductor encapsulant or a printed wiring board and has a good hue. More specifically, the present invention relates to a method for producing a phenol resin having an improved hue by performing a specific treatment after a reaction between a phenol and a specific unsaturated hydrocarbon. The epoxy resin obtained by glycidylation of the phenol resin has good curability, and the cured product is excellent in electrical properties, heat resistance, solvent resistance, acid resistance, moisture resistance, and the like.

[0002]

2. Description of the Related Art Hydrocarbon-phenol resins obtained by reacting phenols with unsaturated hydrocarbon compounds in the presence of an acid catalyst such as boron trifluoride complex or sulfuric acid have excellent moisture absorption resistance. However, since the produced resin is significantly colored, its use may be limited. Therefore,
JP-A-7-252349 proposes a method for improving the hue by stirring and mixing the mixture after the reaction with an inorganic porous material in an organic solvent. In the above method, the clay treatment is performed after the removal of unreacted phenols.However, when phenols which are polar compounds are present, the clay is adsorbed on the clay and there is a concern that the decolorizing effect of the clay is reduced. Because there is. According to the above method,
Although it is possible to achieve a certain hue improvement, it is necessary to remove unreacted phenols from the reaction product, dilute it with an organic solvent, and remove the solvent again. There is a problem in the point. Further, in the above method, since the boron fluoride catalyst is deactivated by the alkali, a catalyst residue is generated by the decomposition of the catalyst. Therefore, it is necessary to remove the catalyst residue remaining in the resin.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a method for easily producing a phenol resin having an excellent hue in a small number of steps.

[0004]

That is, the first aspect of the present invention is as follows.
The present invention relates to a method for producing a phenol resin having an excellent hue, comprising the following steps (I) to (IV). (I) a step of reacting an unsaturated hydrocarbon compound having two or more carbon-carbon double bonds with an excess of phenols in the presence of a boron trifluoride-based catalyst substantially without a solvent;
(II) a step of deactivating the catalyst in the reaction solution using an ion exchanger, (III) a step of decoloring by adding an inorganic porous substance and stirring and mixing without removing unreacted phenols, And (IV) removing solid substances and unreacted phenols, respectively. A second aspect of the present invention relates to the method for producing a phenol resin having an excellent hue in which the inorganic porous material is clay, according to the first aspect. The method of the present invention can achieve a certain hue improvement effect with fewer steps as compared with the method described in the above publication.
Also, the amount of boron in the resin due to the residual catalyst is small, which is a preferable method.

[0005]

Next, the present invention will be described in more detail. In the method for producing a phenolic resin of the present invention, first, as a step (I), a phenol is reacted with an unsaturated hydrocarbon compound having two or more carbon-carbon double bonds in the presence of a boron trifluoride-based catalyst. Let it. More specifically, as the unsaturated hydrocarbon compound, a hydrocarbon having a relatively small molecular weight having two or more carbon-carbon double bonds (hereinafter referred to as “hydrocarbon (1)”) and a chain conjugate such as butadiene are used. A diene polymer (hereinafter, referred to as “hydrocarbon (2)”) is exemplified. The hydrocarbon (1) preferably has 4 to 16 carbon atoms, specifically, a chain conjugated diene compound such as butadiene, isoprene and piperylene, cyclopentadiene,
Cyclic diene compounds such as methylcyclopentadiene, dicyclopentadiene, limonene, vinylcyclohexene, tetrahydroindene, and mixtures thereof, and Diels-based compounds using conjugated diene compounds among the above compounds
Alder reaction products, such as the Diels-Alder reaction product of butadiene and cyclopentadiene, are exemplified.

The number average molecular weight of the butadiene polymer used as the chain conjugated diene polymer of the hydrocarbon (2) is 3
It is preferably from 0.00 to 4,000, and more preferably from 500 to 3,000. Examples of the butadiene polymer include a homopolymer of butadiene and a copolymer of butadiene and another comonomer. Other copolymerizable comonomers include, for example, conjugated diolefins such as isoprene and piperylene, and styrene, α-
Examples thereof include aromatic vinyl monomers such as methylstyrene, vinyltoluene, and vinylbenzene. The butadiene copolymer can be obtained by subjecting these to block or random copolymerization with butadiene. The mixing ratio of butadiene and the other comonomer is 0.1 mol of the other comonomer per 1 mol of butadiene.
It is preferably from 0.5 to 0.8 mol, and particularly preferably from 0.1 to 0.7 mol.

Preferred unsaturated hydrocarbon compounds include, as the hydrocarbon (1), a cyclic diene compound represented by dicyclopentadiene and a Diels-Alder reaction product using the same, and as the hydrocarbon (2), It is a butadiene polymer.

As the phenol used in the present invention, for example, a phenol represented by the following general formula [1], an alkyl naphthol represented by the following general formula [2], or a mixture thereof is preferable.

[0009]

Embedded image (In the formula, R ₁ is a hydrogen atom, a halogen atom, and has 1 to 1 carbon atoms.
And 10 alkyl groups, cycloalkyl groups or aryl groups. M and n each represent an integer of 1 to 3. )

[0010]

Embedded image (Wherein, R ₂ is a hydrogen atom, a halogen atom, a carbon number of 1 to
And 10 alkyl groups, cycloalkyl groups or aryl groups. Further, q and p each represent an integer of 1 to 3. )

When m, n, p or q in the above formula is 4 or more, it is difficult to manufacture, so that those values are preferably 3 or less. As the phenols, specifically, for example, phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-isopropylphenol, m-propylphenol, p-propylphenol, p-sec-butylphenol, p-tert-
Butylphenol, p-cyclohexylphenol, p
Monohydric phenols such as chlorophenol, o-bromophenol, m-bromophenol, p-bromophenol; resorcin, catechol, hydroquinone,
2-bis (4'-hydroxyphenyl) propane, 1,1 '
-Bis (dihydroxyphenyl) methane, 1,1'-bis
Examples include naphthols such as (dihydroxynaphthyl) methane; dihydric phenols such as tetramethylbiphenol and biphenol; trihydric phenols such as tris (hydroxyphenyl) methane and mixtures thereof. In particular, phenol, o-cresol, m-cresol, 2,2-bis (4'-hydroxyphenyl) propane and the like are desirable from the viewpoint of economy and ease of production.

The charging ratio of the phenol and the hydrocarbon (1) or the hydrocarbon (2) is such that the phenol is usually 0.8 to 20 molar equivalents relative to the hydrocarbon (1) or (2), Preferably it is 1 to 15 times molar equivalent. When the charge ratio of phenols is less than 0.8 molar equivalents, homopolymerization of hydrocarbons occurs simultaneously, and when it exceeds 20 molar equivalents, it becomes difficult to recover unreacted phenols. Absent.

The catalyst used for reacting the phenols with the hydrocarbon (1) or the hydrocarbon (2) is a boron trifluoride-based catalyst. Examples of the catalyst include boron trifluoride, a boron trifluoride ether complex, a water complex, an amine complex, a phenol complex and an alcohol complex. These are preferred from the viewpoint of activity and ease of removal of the catalyst, and among them, boron trifluoride and boron trifluoride-phenol complex are most desirable.

The amount of the catalyst used is not particularly limited and can be appropriately selected depending on the catalyst used. In the case of the boron trifluoride-phenol complex, the hydrocarbon (1) or the hydrocarbon (2 ) 0.1 to 100 parts by weight
To 20 parts by weight, preferably 0.5 to 10 parts by weight.

The reaction between the phenols and the hydrocarbon (1) or the hydrocarbon (2) is carried out using a large excess of phenols without using a solvent. That is, the phenol is at least equimolar equivalent to the hydrocarbon (1) or the hydrocarbon (2),
Preferably, 3 to 15 times molar equivalent is used.

The reaction temperature in the above-mentioned reaction varies depending on the type of the catalyst used. For example, when a boron trifluoride-phenol complex is used, the reaction temperature is usually 20 to 170 ° C., preferably 50 to 150 ° C. If the reaction temperature exceeds 170 ° C., decomposition of the catalyst or a side reaction occurs.

In the above-mentioned reaction, in order to make the reaction proceed smoothly, it is preferable to reduce the water content in the system as much as possible, and it is particularly desirable to keep the water content at 100 ppm or less. Further, in the above reaction, it is preferable to carry out the polymerization while sequentially adding the hydrocarbon (1) or the hydrocarbon (2) from the viewpoint of preventing the homopolymerization of these hydrocarbons and controlling the heat of reaction.

After the completion of the reaction, a catalyst deactivation treatment is performed as a step (II). That is, the catalyst is deactivated by adding an ion exchanger in an amount of 1 to 10 times the molar amount of the boron trifluoride-based catalyst. As the ion exchanger, an inorganic ion exchanger is preferable, and hydrotalcites are particularly preferable. The catalyst is ion-exchanged and taken into the ion exchanger.

After the catalyst is deactivated, the reaction product is decolorized as a step (III). In the decolorizing method of the present invention, without removing the unreacted phenols, the reaction solution containing the deactivated catalyst, the unreacted phenols and the ion exchanger is brought into contact with the inorganic porous material by removing the catalyst. And stir and mix. The inorganic porous material used here is not particularly limited, but usually one having an apparent specific gravity of 0.25 to 0.85 is used.
Also, in order to increase the contact area with the reaction solution during stirring and mixing, to facilitate the adsorption of impurities in the reaction product, and to improve the decolorizing effect, it is preferable that the particle diameter is smaller, specifically, as fineness Those having a passing amount of 75% or more through 200 mesh are preferable.

Specific examples of such an inorganic porous material include activated clay, acid clay, silica-magnesia-based synthetic gel (preferably decolorized and deoxidized), and silica-alumina-based synthetic gel (preferably decolorized, Deoxidized)
And the like. Among them, activated clay is preferred because of its good decolorizing effect. The activated clay preferably used in the present invention comprises 75 to 85% of silicon dioxide and 9 to 13% of aluminum oxide, and the effect of the present invention is more remarkably exhibited by using the same.

The amount of the inorganic porous substance to be mixed is not particularly limited and can be appropriately selected depending on the type of the reactant and the decolorizing effect. For example, when phenol and dicyclopentadiene are reacted, By using 10% by weight or more of the amount of dicyclopentadiene, a sufficient decoloring effect can be obtained. The conditions for stirring and mixing can be appropriately selected according to the properties of the inorganic porous material. For example, in the case of decolorization with activated clay, the stirring temperature is set to 80 ° C.
When performed at a temperature in the range of ~ 120 ° C, a preferable decoloring effect is obtained,
A high temperature of 150 ° C. or more is not preferable because the activated clay is decomposed and the decolorizing effect is remarkably poor.

After the above stirring treatment, as a step (IV), solid substances and unreacted phenols are removed. First,
By filtering the treatment liquid, it is possible to remove an ion exchanger, an inorganic porous substance, and a catalyst residue as a deactivator. In the filtration, the workability can be improved by adding a solvent as needed or increasing the temperature of the reaction solution. As the solvent added here,
A hydrocarbon solvent having 3 to 10 carbon atoms or a derivative thereof is preferable. Specifically, benzene, toluene, o-xylene, p-xylene, m-xylene, mesitylene, acetone, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, methanol, Ethanol, propyl alcohol, isopropyl alcohol, butanol, isobutyl alcohol, diethyl ether, dibutyl ether, diisobutyl ether, tetrahydrofuran, ethyl cellosolve, butyl cellosolve, dimethyl diglycol, dimethyl triglycol, methyl propylene glycol, etc. are preferred, among which benzene, toluene And xylenes are more preferred. By the above-mentioned filtration, an ion exchanger and an inorganic porous substance are removed, and a filtrate containing a phenol resin and unreacted phenols is obtained.

Finally, if unreacted phenols are concentrated and distilled off from the filtrate by distillation, a phenol resin having an improved hue can be obtained. The concentration conditions are not particularly limited, and the distillation pressure may be normal pressure, reduced pressure, increased pressure, or a combination thereof. Concentration temperature is 10
It is preferably performed in the range of 0 to 300 ° C, more preferably 150 to 270 ° C, and still more preferably 170 to 250 ° C.
It is in the range of ° C. If the concentration temperature exceeds 300 ° C., there is a concern that decomposition of the resin and the like may occur. Further, nitrogen or steam may be blown into the system in order to make the concentration proceed smoothly and quickly.

The phenolic resin obtained by the above method has an improved hue and does not contain catalyst residues and unreacted phenols. Therefore, a curing agent for a cured epoxy resin, a raw material for an epoxy resin and a raw material for a cyanate resin are obtained. Can be used as

[0025]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. <Example 1> (Synthesis of phenol resin-1) Phenol 2,000 g
And 400 g of toluene were charged into a 5 liter reactor equipped with a reflux condenser (Liebig condenser).
By heating to 170 ° C., 350 g of toluene was distilled off, and the water content in the reaction system was set to 70 ppm. Next, the reaction system was cooled to 70 ° C., and after adding 10 g of boron trifluoride-phenol complex, while controlling the reaction temperature to 70 ° C., dicyclopentadiene 4 having a water content of 20 ppm was added.
00 g gradually over 1.5 hours.
The reaction was performed at 100 ° C. for 4 hours. After completion of the reaction, the obtained reaction product was cooled to 80 ° C., and a hydrotalcite compound (trade name: KW-1000, manufactured by Kyowa Chemical Industry Co., Ltd.) 3
0 g was added and stirred for 1 hour to deactivate the catalyst. Subsequently, the temperature of the obtained reaction product was raised to 100 ° C., 100 g of activated clay was added, and the mixture was stirred and mixed for 1 hour. After that, the solid matter was removed by filtration, and the unreacted phenol was concentrated and recovered to obtain a phenol resin (A). 970 g). The obtained phenol resin has a softening point of 95 ° C. and a phenolic hydroxyl equivalent of 170.
g / eq. The Gardner color number of the resin measured with a 50% dioxane solution was 12.

<Example 2> (Synthesis of phenol resin-2) Instead of phenol, o
-Reaction and purification were carried out in the same manner as in Example 1 except that 2,300 g of cresol was used, and the phenol resin (B) 6
00 g were obtained. The obtained phenol resin (B) had a softening point of 83 ° C. and a phenolic hydroxyl equivalent of 185 g / eq. The Gardner color number with a 50% solution of dioxane was 10.

<Example 3> (Synthesis of phenolic resin-3) Phenol 2,000 g
And 400 g of toluene were charged into a 5 liter reactor equipped with a reflux condenser (Liebig condenser).
By heating to 170 ° C., 350 g of toluene was distilled off, and the water content in the reaction system was set to 55 ppm. Next, the reaction system was cooled to 70 ° C., and after adding 16 g of boron trifluoride-phenol complex, while controlling the reaction temperature to 70 ° C., tetrahydroindene 3 having a water content of 20 ppm was used.
50 g was gradually added dropwise over 1.5 hours, and after completion of the addition,
The reaction was performed at 100 ° C. for 4 hours. After completion of the reaction, the obtained reaction product was cooled to 80 ° C., and a hydrotalcite compound (trade name: KW-1000, manufactured by Kyowa Chemical Industry Co., Ltd.) 3
0 g was added and stirred for 1 hour to deactivate the catalyst. Subsequently, the temperature of the obtained reaction product was raised to 100 ° C., 80 g of activated clay was added, and the mixture was stirred and mixed for 1 hour. Then, solid matter was removed by filtration, and unreacted phenol was recovered by evaporation to obtain a phenol resin (C). ) 800 g were obtained. The obtained phenol resin (C) had a softening point of 104 ° C. and a phenolic hydroxyl equivalent of 156 g / eq. The Gardner color number of the resin measured with a 50% dioxane solution was 12.

<Comparative Example 1> (Synthesis of phenolic resin-4) Solids were removed by filtration without adding activated clay to the reaction solution after addition of the hydrotalcite compound, and unreacted phenol was evaporated and recovered. Reaction and purification were carried out in the same manner as in Example 1 except that
A phenol resin (D) 930 was obtained. The obtained phenol resin (D) had a softening point of 94 ° C. and a phenolic hydroxyl equivalent of 170 g / eq. The Gardner color number in a 50% dioxane solution was 17.

[0029]

According to the method of the present invention, the decolorization treatment can be performed even in the presence of a phenol which is a polar compound which can be an obstacle to the decolorization treatment. Therefore, the treatment can be performed before the excess phenols are removed by evaporation. In addition, in the method disclosed in the above-mentioned publication or the like, which involves hydrolysis of a boron trifluoride-based catalyst with an alkali, it is difficult to remove the catalyst residue generated by the decomposition, so that the catalyst residue may remain in the resin and cause a problem. However, according to the method of the present invention, substantially no catalyst residue is generated, and the problem of the residual catalyst can be avoided. The phenolic resin obtained by the production method of the present invention has a good hue, and therefore is used as a curing agent for a cured epoxy resin in the production of a semiconductor encapsulant or a printed wiring board, or as a raw material for an epoxy resin by glycidylation. By using, hue is good, and heat resistance, solvent resistance, acid resistance,
A cured product excellent in moisture resistance, electrical characteristics, and the like can be obtained.

Claims (2)

[Claims] 1. A method for producing a phenol resin having an excellent hue, comprising the following steps (I) to (IV). (I) a step of reacting an unsaturated hydrocarbon compound having two or more carbon-carbon double bonds with an excess of phenols in the presence of a boron trifluoride-based catalyst substantially without a solvent;
(II) a step of deactivating the catalyst in the reaction solution using an ion exchanger, (III) a step of decoloring by adding an inorganic porous substance and stirring and mixing without removing unreacted phenols, And (IV) removing solid substances and unreacted phenols, respectively 2. The method according to claim 1, wherein the inorganic porous material is clay.