JPS603328B2 - Method for producing phenolic resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a process in which isoprobenylphenol or oligomers of improbenylphenol represented by formula (0) or formula (m), alone or as a mixture, and dehydrated castor oil are combined under an acidic catalyst. After the reaction, isoprobenylphenol or isoprobenylphenol oligomers represented by formula (0) or formula (m) alone or in a mixture and dehydrated castor oil are acidified in the presence of phenols. After reacting under a catalyst (first stage modification), further reacting with phenols under an acidic catalyst (second stage modification), and then reacting the reaction product with formaldehyde as part of the phenol component. The present invention relates to a method for producing a characteristically modified phenolic resin.

The purpose of the present invention is to effectively modify dehydrated castor oil with a low content of conjugated double bonds, without sacrificing the excellent properties of conventional phenolic resins mainly composed of phenols. A method for producing a phenolic resin useful as an electrical insulating material, a laminate, and a decorative board, which has significantly improved flexibility without impairing various properties such as electrical properties, heat resistance, chemical resistance, dimensional stability, and warpage. It provides:

Conventionally, a base material is impregnated with a resol-type phenolic resin obtained by reacting phenols such as phenol, cresol, and xylenol with formaldehyde and dried, and the base material impregnated with side resin is used as a laminated material with a predetermined composition. It is well known to obtain a laminate by heating and pressurizing the laminate.

These laminates are widely used industrially as electrical insulating materials, structural materials, etc., but in recent years, with the development of electrical and electronic equipment, various laminates have been used for communication,
Simplification of the mounting method of parts of consumer equipment, etc. 4. Moldization,
As performance increases, electrical insulation, heat resistance, and mechanical performance are improved.
There has been an increasing demand for laminates with good punchability and a well-balanced variety of properties. In addition, there is a great demand for printed wiring materials, and in this field they are used by punching them into desired shapes, but phenolic resin is hard and brittle, so it must be heated to 100 to 150 q0 during punching. Since the processing must be carried out by the process, there are drawbacks such as dimensional changes due to expansion and contraction, warping due to changes in residual stress, etc., and the heating operation is a complicated process. For this reason, various methods have been proposed for producing phenolic resin laminates having these properties. In particular, in order to maintain punching workability, it has been proposed for a long time to use a drying oil having a conjugated double bond, such as tung oil, citrus oil, and dehydrated castor oil.

However, although modification by simply adding drying oil improves punching workability, other properties are significantly inferior, so methods have been proposed in which the drying oil is further modified.

For example, by reacting drying oil with phenols under an acidic catalyst and then reacting with formalin,
This method increases crosslinking density while maintaining punching workability due to tough oil and prevents deterioration of other properties.

Drying oils with non-conjugated double bonds, such as linseed oil and perilla oil, have low chemical reactivity, so the ratio of phenols introduced into the drying oil is low, and sufficient crosslinking reaction does not proceed, resulting in poor internal hardening of the laminate. It is difficult to obtain a laminate due to the poor quality.

Even if a laminate can be manufactured under special conditions, there are disadvantages in that the layers may peel off during punching, or the resin may be eluted by boiling in a solvent such as trichloride for several minutes, causing the layers to separate. Dehydrated castor oil is a glyceride of ricinoleic acid, the main component of castor oil, that has been dehydrated or nolic acid.
An example of its fatty acid composition is 29% conjugated linoleic acid, 58% unconjugated linoleic acid, 7.5% oleic acid, 5.0% ricinoleic acid, palmitic acid, and 0.5% stearic acid. Therefore, the content of conjugated double bonds is low, and the introduction of phenols into the dehydrated castor oil necessary for manufacturing laminates is insufficient, resulting in laminates with good electrical and mechanical performance, chemical resistance, moisture resistance, and water resistance. You can't get it. For this purpose, Hakama Kosho 45-35918 adopted a method in which dehydrated castor oil and phenol were reacted at high temperature in the presence of a sulfuric acid catalyst. In order to improve the moisture and water resistance of the phenol resin, it is necessary to wash away the young nitrate produced by neutralization, and the resulting laminate is also difficult to put to practical use.

Tung oil (produced in China) with a high content of conjugated double bonds is a fatty oil with the highest chemical reactivity among drying oils containing about 80% conjugated trienes.

An example of its fatty acid composition is Q-ereostearic acid 81.5
%, linoleic acid 6.7%, oleic acid 6.4%, stearic acid 2.9%, and palmitic acid 2.5%. Therefore, since tung oil has 81.5% conjugated double bonds in its main chain, it easily reacts with phenols under acidic catalysts. The thus obtained product of phenols and tung oil makes it possible to produce laminates that are well-balanced in terms of electrical and mechanical properties as well as processability. However, when using phenolic modified tung oil, However, the crosslinking density of the resin is still insufficient for miniaturized laminates for precision applications, and the interlayer adhesion of the laminate is far from satisfactory. The reason for this is that the reaction between tung oil and phenols under an acidic catalyst is a Friedel-Crach reaction, but under this reaction condition, tung oil is easy to polymerize and the impregnation effect of the resin into the resin is poor, and the phenol This is because sufficient crosslinking and curing reactions do not proceed because the ratio of introduction into tung oil is small. In view of the above, it is considered essential that the drying oil used in the laminate contains a large amount of conjugated double bonds and has high reactivity with substances such as phenols.

As a result of various research aimed at resolving the above-mentioned drawbacks, the present inventors have discovered a method of extremely effectively modifying dehydrated castor oil, which has a low content of conjugated double bonds, and has found a method for extremely effectively modifying dehydrated castor oil, which was previously thought to be unusable. Enables the use of dehydrated castor oil.

That is, after reacting isoprobenylphenol or isoprobenylphenol oligomers represented by formula (0) or formula (m) alone or in a mixture with dehydrated castor oil under an acidic catalyst, or after reacting isoprobenylphenol with After reacting an oligomer of isoprobenylphenol or isoprobenylphenol represented by formula (0) or formula (m) alone or in a mixture with dehydrated castor oil in the presence of a phenol under an acidic catalyst, (1st stage modification), further reacts with phenols with or without adding an acid catalyst as necessary (2nd stage modification), and then converts the reaction product into formaldehyde as part of the phenol component. Discovered a method for modifying dehydrated castor oil by reacting it with phenolic resin, and by applying this method to a method for producing phenolic resin, succeeded in producing a phenolic resin with properties equivalent to or superior to modified tung oil phenolic resin, and achieved the method of the present invention. did. The method of the present invention involves using dehydrated castor oil having a conjugated double bond and isoprobenylphenol or isoprobenylphenol oligomers represented by formula (b) or formula (m) alone or as a mixture under an acidic catalyst. The present invention provides a method for producing a phenol resin, which comprises reacting the resin with phenol under an acidic catalyst, and then reacting the reaction product with formaldehyde as part of the phenol component.

The effects obtained by the present invention can be summarized as follows by comparing the conventional method of modifying dehydrated castor oil with phenols, the reactivity of the modified dehydrated castor oil with formaldehyde, and the physical properties of the resulting resin.

■ Dehydrated castor oil, which has a low content of conjugated double bonds, can be modified under relatively mild conditions, and by appropriately selecting reaction conditions, it is possible to modify isoprobenylphenol even in the presence of phenols. can preferentially introduce its oligomers into dehydrated castor oil.

■ A large amount of oxyphenyl nuclei are dried by a two-stage modification method in which phenols are further introduced into dehydrated castor oil containing isobrobenylphenol or its oligomer (first stage modification) under an acidic catalyst (second stage modification). It can be introduced into the oil to increase the crosslinking density of the resin.

It also improves compatibility with other phenolic resins. ■ Modified dehydrated castor oil reacts quickly with formaldehyde.

The reactivity ratio between dehydrated castor oil modified with isoprobenylphenol or isoprobenylphenol oligomer according to the present invention and formalin is about twice that of conventional dehydrated castor oil modified with phenols.

■ The resulting resin varnish has excellent uniformity and stability.

The laminate obtained by impregnating a resin varnish into a base material and applying heat and pressure has high interlayer bonding strength and crosslinking density, so it has excellent moisture and water resistance.
Heat resistance and voltage resistance characteristics are improved. Therefore, the laminate obtained by impregnating the modified phenolic resin obtained by the method of the present invention with a resin varnish obtained by converting it into a resol has all the above-mentioned advantages, so it has excellent electrical, mechanical properties, moisture resistance, and water resistance. It has excellent properties such as dimensional stability and warpage.

Dehydrated castor oil in the present invention refers to conjugated linoleic acid produced by dehydrating castor oil in the presence of a catalyst or without a catalyst;
It is a triglyceride whose main component is unconjugated linoleic acid. It contains 20 to 50% of the common mineral.
For example, product names: ・Igen (Shinken Kagaku), D. C. ○
(Ito Oil Co., Ltd., Nicca Oil Co., Ltd.), etc. In the present invention, dehydrated castor oil refers to triglycerides of conjugated linoleic acid and non-conjugated linoleic acid;
Esters with alcohols or polyhydric alcohols are also broadly included. In the present invention, the reaction of isoprobenylphenol or oligomers of isoprobenylphenol represented by formula (b) or formula (m) alone or in a mixture with dehydrated castor oil or the presence of phenols Reaction of isoprobenylphenol or oligomers of isoprobenylphenol represented by formula (0) or formula (m) alone or in mixture with dehydrated castor oil (
The acidic catalysts used in the first stage modification are mineral acids such as sulfuric acid, phosphoric acid, hydrochloric acid and shelf acid, organic acids such as P-toluenesulfonic acid and Hakama acid, and also sulfonic acid type or carboxylic acid type enteric ions. It is an exchange resin, and the amount used is 100% based on the reactants.
A range of ~1000 wind, especially 300-400 blood is preferred.

The reaction temperature and time are 0.5 to 65 to 150q○.
3 hours are used, preferably at 85-100°C for 1-3 hours.
A range of 2 hours is appropriate. The reaction of dehydrated castor oil with isoprobenylphenol or its oligomers gives very favorable results in the presence of other phenols that have low reactivity with the latter. This is because it is preferable to carry out the reaction under dilution in terms of inhibiting the polymerization of dehydrated castor oil and dissolving the isoprobenylphenol oligomer. Phenols used in the present invention include phenols that easily react with isoprobenylphenol or its oligomers, such as phenol, cresol, xylenol, tecol, resorcin, and those that do not easily react with isoprobenylphenol or its oligomers. Phenols, such as butylphenol, octylphenol,
Nonylphenol, dodecylphenol, bisphenol A, phenylphenol, styrenated phenol,
Cumilphenol and the like.

In the present invention, the catalyst used for the reaction of the reaction product of dehydrated castor oil and isoprobenylphenol or its oligomer with phenols (second stage modification) is P-toluenesulfonic acid, sulfuric acid, hydrochloric acid, etc. The amount of catalyst used is preferably in the range of 300 to 300 ml per reactant.

There are no limitations on the reaction temperature and time, but 80-11
The preferred time is 0.5 to 3 hours at 0°C. As a result of studying the reaction mechanism and reaction products of the reaction of isobrobenylphenol or its oligomer with dehydrated castor oil and the reaction of the reaction product with phenols, the following matters were clarified.

For example, in the reaction of methyl ester of 9111-octadecadienoic acid, which is a component fatty acid of dehydrated castor oil, and P-isoprobenylphenol or its oligomer under an acidic catalyst, for example, a phosphoric acid catalyst is used. 2
The reaction product when reacted for a certain period of time is 2 molecules of P-isoprobenylphenol or 1 molecule of P-isoprobenylphenol dimer added to 9,11-octadecadienoic acid methyl ester. This became clear from gas chromatography and mass spectra.

Furthermore, the results of analysis of the product by infrared absorption spectrum and nuclear magnetic resonance spectrum revealed that the conjugated diene of 9,11-octadecadienoic acid remained intact. From the above results, it is estimated that the first-stage modified product of dehydrated castor oil in the method of the present invention has the following chemical structure (Formula 14).

(However, R represents a glyceride residue, and R2 and R3 both represent a group, or one of R2 and R3 represents a hydrogen atom and the other represents a group.

) When the reactant (Formula-4) is reacted with cresol at 100° C. for 1 hour in the presence of a sulfuric acid catalyst, a cresol-modified product (Formula-5) is obtained.

(However, R4 represents a hydrogen atom or at least one group.

) On the other hand, the modified product obtained by the related method of modifying dehydrated castor oil with phenols was published in Japanese Patent Publication No. 45-35.
As described in 918, it is a product of the so-called Friedel-Crafts reaction, and is as follows.

(However, R5 represents a hydrogen atom or at least one group.

) As is clear from the above facts, in the method of modifying dehydrated castor oil according to the method of the present invention, even after modification with isoprobenylphenol or its oligomer, a conjugated gene exists, so a phenyl nucleus is further introduced. be able to.

Therefore, the present invention increases the ratio of phenyl nuclei introduced per molecule of dehydrated castor oil compared to conventional modification methods. These differences are due to the hardness of the resin obtained after the reaction of modified dehydrated castor oil with formalin, which changes its properties. That is, according to the conventional method, the crosslinking reaction of the resin is achieved only by methylolation of the phenols added to dehydrated castor oil, whereas in the method of the present invention, the crosslinking reaction of the resin is achieved by methylolation of the introduced improvenylphenyl nucleus. This can also be achieved using methylolated compounds.

The modified dehydrated castor oil obtained by the method of the present invention has a high introduction rate of methylol groups through the reaction with formalin, and the modification conditions are milder than in the conventional method, and unnecessary polymerization of dehydrated castor oil can be avoided. The impregnation effect of the phenolic resin into the laminate base material is far superior, and it is presumed that this contributes to increasing the crosslinking density after laminate molding and improving the interlayer bonding strength.

As is clear from the above explanation, the modification effect in the present invention is characterized by improved reactivity with formalin, increased introduction ratio of phenyl nuclei, etc., which improves the impregnating effect of the resulting phenol resin and improves the properties of the varnish. , an increase in hardening density is achieved, and as a result, the interlayer bonding strength of the resin immersion laminate is increased, and thermal, electrical, mechanical properties, and chemical resistance are greatly improved. It is.

In order to effectively achieve the method of the present invention, when modifying dehydrated castor oil, isoprobenylphenol or its oligomer is added in an amount of 0.1 to 2 times the weight ratio of dehydrated castor oil.
Preferably 0.3-1. Use within the maximum volume range.

Isoprobenylphenol or its oligomer used in the method of the present invention has the general formula 1. B. It is a compound represented by m and "(Formula D, in m, n represents an integer of 0 to 18.

) In each of the above formulas, the hydroxyl group may be located at any of the ortho, meta, or para positions. Although monomers, dimers, and trimers can be synthesized as pure compounds, oligomers of tetramer or higher coexist as a mixture. These monomers and oligomers can be used either singly or as a mixture. In the method of the present invention, the phenol resin is produced by reacting it with formaldehyde under acidic or alkaline conditions after the modification reaction is completed. A method of obtaining a novolak type resin by reacting with formaldehyde under acidic conditions, a method of obtaining a novolak type to resol type resin by partially reacting with formaldehyde under acidic conditions, then making it alkaline and then reacting with formaldehyde, or a method of obtaining a novolak type to resol type resin by reacting it partially with formaldehyde under acidic conditions, or making it alkaline after a modification reaction. Any method of obtaining a resol-type resin is possible. In order to obtain a resol type resin, the acidic catalyst used for modification is neutralized with ammonia, organic amines, etc., and then subjected to a reaction with formaldehyde. Formaldehyde used in the reaction with formaldehyde and all the phenols in the raw materials/
The molar ratio of phenols is generally in the range of 0.7 to 2.0, preferably 0.8 to 1.6.

There are no particular limitations on the reaction temperature and time, but 80-11
000 for 1 to 5 hours is preferred. As a catalyst, when producing novolac type resin, hydrochloric acid, Hakama acid, P-toluenesulfonic acid, sulfuric acid, etc. are used, and when producing resol type resin, ammonia, methylamine, dimethylamine, triethylamine, ethylenediamine, jetylamine, etc. , caustic soda, caustic potash, etc. are used. Although the amine catalyst can of course be used alone, it is preferable to use the ethylenediamine catalyst and another amine catalyst together. The amount of dehydrated castor oil used to achieve the excellent effects of the method of the present invention is 10
10 to 60 parts by weight, preferably 25 to 60 parts by weight
The range is 50 parts by weight. As the formaldehyde, formalin aqueous solution, paraformaldehyde, etc. are generally used. After the reaction is completed, the resin is dehydrated and dissolved in aromatic hydrocarbons, ketones, or alcohols to obtain a varnish. The effects of the present invention will be explained below using Examples.

Example 1 P-isoprobenylphenol 340% and dehydrated castor oil 500% having a composition of 95% by weight of P-isoprobenylphenol, 3% by weight of 2-mers, 2% by weight of trimers and tetramers
Keep the temperature at 140℃ at night. 2.2 hours of 85% phosphoric acid was charged and stirred for 2 hours.

After the reaction, cool and add 244 g of synthetic cresol (60% m-form, 40% P-form) and 7.0 g of 20% sulfuric acid to give 100 g.
00 for 1 hour. Then phenol 544,
Octylphenol 266%, Nonylphenol 266%
In the evening, add 1278 g of 37% formalin, 41 g of 2454% ammonia water and 3.9 g of ethylenediamine.
The reaction was carried out at 100°C for 5 hours. Water was removed under reduced pressure, and when the content reached 90 to 95°C, dehydration was stopped and cooled, dissolved in a mixed solvent of methanol and toluene 2:1 to a resin concentration of 5.
A 0% varnish was obtained. A linter paper having a thickness of 10 mils was impregnated with the above resin varnish and dried to obtain a prepreg with a resin content of 45%.

Laminate molding by stacking 9 sheets of this prepreg (90k9/base,
160oo, 50 minutes) to obtain a laminate. In addition, a copper-clad laminate with 35 French steel plates attached was also obtained. The thickness of each laminate was 1.6 ribs. Example 2 Weight % of P-isoprobenylphenol 2, dimer 69
A mixture of isobrobenylphenol and its oligomers having a composition of 5% by weight, 5% by weight of trimers, and 6% by weight of tetramers, 340 μm of isobrobenylphenol, 266 μm of nonylphenol, and 660 μm of dehydrated castor oil for 100 μm. 5. Keep it under 20% sulfuric acid.
I put in 5 evenings and lit a light for 2 hours.

After the reaction, further synthesized cresol (60% m, 4
0%) 240 hours and 20% sulfuric acid 5.1 hours added to 1000
The reaction was carried out at 0 for 1 hour. Next, phenol 544 times, octyl phenol 266 times, 37% formalin 1278 times.
Then, 40.5 hours of 24.54% ammonia water and 3.9 hours of ethylenediamine were added, and the mixture was reacted at ~100°C for 4 hours. Water was removed under reduced pressure, and when the temperature of the contents reached 90 to 95°C, dehydration was stopped and the contents were cooled. methanol, toluene2
:1 to obtain a varnish with a resin concentration of 50%. A laminated shelf weave laminated fabric with a thickness of 1.6 pigs according to the same treatment as in Example 1.

Example 3 Weight % of P-isoprobenylphenol 1, 2 base body 75
A mixture of isoprobenyl phenol and its oligomers having a composition of 8% by weight of triplers and 7% by weight of tetramers was heated to 85° C. under an air conditioner. Add 20% sulfuric acid 6.2 hours and add 2
I worshiped the time light.

After the reaction, cool and add 250 g of synthetic cresol (60% of m-isomer, 40% of phosphorus) and 5.0 g of 20% sulfuric acid to 100 g.
The reaction was carried out at ℃ for 1 hour. Next, 330 parts of phenol, 48 parts of nonylphenol, 1,410 parts of formalin, 48 parts of nonylphenol, 50 parts of 24.54% ammonia, and 4 parts of ethylenediamine.
The mixture was reacted for 4 hours at 98 to 100°C.

Water was removed under reduced pressure, and when the content reached 90 to 9yo, dehydration was stopped, cooled, and dissolved in a 2:1 mixed solvent of methanol and toluene to obtain a varnish with a resin concentration of 50%. A 1.6-thickness laminate and a copper-clad laminate were obtained in the same manner as in Example 1.

Example 4 P having a composition of 2% by weight of P-isoprobenylphenol, 2% by total weight, 5% by weight of trimer, and 5% by weight of tetramer.
- Isoprobenylphenol and its oligomer mixture 3302, synthetic cresol (60% m, 4
0%) 167 yen and dehydrated castor oil 500 yen were kept at 85° C. under the air conditioner, and 40% sulfuric acid 3.2 yen was placed in a bag and stirred for 2 hours.

After the reaction, synthetic cresol (60% m-isomer, 40% P-isomer)
) 250 hours and 40% sulfuric acid for 2.5 hours at 100℃.
Allowed time to react. Next, phenol 293 days, nonylphenol 120 days, octylphenol 120 days, 37 days
% formalin 704%, 24.54% ammonia water 25
97～Noriko○ by adding 2.2 g of ethylenediamine and 2.2 g of ethylenediamine
The reaction was carried out for 2.5 hours.

Water was removed under reduced pressure, and when the content reached 90 to 90%, dehydration was stopped, cooled, and dissolved in a mixed solvent of methanol and toluene 2:1 to obtain a varnish with a resin concentration of 50%. Following the same treatment as in Example 1, a laminated fine board with a thickness of 1.6 ribs was obtained.

Example 5 P having a composition of 3% by weight of P-isoprobenylphenol, 80% by weight of dimer, 5% by weight of trimer, and 5% by weight of tetramer.
-35 of isoprobenylphenol and its oligomers
0, nonylphenol 266 and dehydrated castor oil 50
The reactor was kept under rinsing at 140°C, charged with 2.5°C of 85% phosphoric acid, and stirred for 2 hours.

After the reaction, cool and add 230 ml of synthetic cresol (60% m-isomer, 40% phosphorus) and 4.6 ml of 20% sulfuric acid.
The reaction was carried out at 0°C for 1 hour. Then phenol 544,
Octylphenol 253%, 37% formalin 128
0 evening and 24. Add 40.5% of ammonia water and 3.9% of ethylenediamine and heat at ~100qC for 4. I reacted for a while.

Water was removed under reduced pressure, and when the content reached 90 to 95 qo, dehydration was stopped, cooled, and dissolved in a mixed solvent of methanol and toluene 2:1 to obtain a varnish with a resin concentration of 50%. Example 1
A laminate with a thickness of 1.6 ribs and a copper-clad laminate were obtained in the same manner as above.

Example 6 P having a composition of 3% by weight of P-isoprobenylphenol, 8% by weight of dimer, 5% by weight of trimer, and 5% by weight of tetramer
- mixture of isoprobenylphenol and oligomers 3
40 liters of water and 500 liters of dehydrated castor oil were kept at 100 mils under the water, 2.2 liters of 85% phosphoric acid was charged, and the mixture was stirred for 2 hours.

After the reaction was cooled, 180 hours of synthetic cresol (60% m, 40% phosphorus), 82 hours xylenol, and 7.5 hours 20% sulfuric acid were added, and the mixture was reacted at 100 hours for 1 hour. Next, 4 hours of phenol, 266 hours of octylphenol, 266 hours of nonylphenol, 1280 hours of 37% formalin, 41 hours of 24.54% aqueous ammonia, and 3.9 hours of ethylenediamine were added, and the mixture was reacted at 98 to 100°C for 4.5 hours. .

Water was removed under reduced pressure, and when the content reached 90 to 95 qo, dehydration was stopped, cooled, and dissolved in a mixed solvent of methanol and toluene 2:1 to obtain a varnish with a resin concentration of 50%. Example 1
A 1.6-thickness laminate and a copper-clad laminate were obtained in the same manner as above.

Example 7 P having a composition of 3% by weight of P-isoprobenylphenol, 8% by weight of 2-base body, 5% by weight of trimer, and 5% by weight of 4-base body.
- isoprobenylphenol and oligomer mixture 3
4M and 500 tons of dehydrated castor oil were kept at 140° C. under concentrated conditions, and 2.2 tons of 85% phosphoric acid was charged and stirred for 2 hours.

After the reaction, it was cooled to give 127% of phenol and 127% of resorcinol.
After adding 7.2 g of 20% sulfuric acid, the mixture was reacted at 100° C. for 1 hour. Next, phenol 520 times, octylphenol 253 times, nonylphenol 280 times, 37% formalin 1278 times and 24 times. Add 40.5 liters of heat % ammonia and 4.30 liters of ethylenediamine to 98-100q.
0 for 4 hours.

Water was removed under reduced pressure, and when the content reached 90 to 95 qo, dehydration was stopped, cooled, and dissolved in a mixed solvent of methanol and toluene 2:1 to obtain a varnish with a resin concentration of 50%. Example 1
A 1.6-thickness laminate and a copper-clad laminate were obtained in the same manner as above.

Comparative Example 1 Cresol 604, dehydrated castor oil 300 and 20%
19.5 hours of sulfuric acid was reacted at 120°C for 3 hours.

After the reaction, cool and add 37% formalin 757 hours, nonylphenol 200 hours, octylphenol 200 hours, 24 hours.
．． Add 28.6 liters of 54% ammonia water and 2.3 liters of ethylenediamine and boil at 97 to 98 qo for 2. I reacted for a while. Water was removed under reduced pressure, and when the content became 90-90%, dehydration was stopped, cooled, and dissolved in a mixed solvent of methanol and toluene 2:1 to obtain a varnish with a resin concentration of 60%. A laminate with a thickness of 1.6 ribs and a copper-clad laminate were obtained in the same manner as in Example 1. Comparative Example 2 Fer/Fal 380 yen, dehydrated castor oil 200 yen and 20%
Sulfuric acid was reacted with 60 ml of sulfuric acid at 12 psi for 4 hours.

After the reaction was cooled, 37% formalin was added for 530 hours, octylphenol for 143 hours, nonylphenol for 143 hours, and 24.
54% ammonia water 20.6 parts and ethylenediamine 1 part
．． The mixture was reacted at 97 to 98 qo for 3 hours. Water was removed under reduced pressure, and when the content reached 90-9C, dehydration was stopped, cooled, and dissolved in a 2:1 mixed solvent of methanol and toluene to obtain a varnish with a resin concentration of 50%. Following the same treatment as in Example 1, a 1.6 willow laminate with a thickness of 1.6 was obtained.

Comparative Example 3 P-isoprobenylphenol and its oligomer having a composition of 3% by weight of P-isoprobenylphenol, 80% by weight of dimer, 5% by weight of trimer, and 5% by weight of 4-base member. Mixture 300 ml, phenol 264 ml and dehydrated castor oil 4 ml
The mixture was kept under concentrated conditions at 85°C for 50 days, and 2.9 degrees of 40% sulfuric acid was added thereto for 2 hours.

Next, synthetic cresol (60% m-form, 40% P-form)
375 evenings, nonylphenol 109 evenings, octylphenol 109 evenings, 37% formalin 6 evenings, 24. Add 22.5% ammonia water and 2.0% ethylenediamine to 97-9800 2. I reacted to the song time.

Water was removed under reduced pressure, and when the content reached 90 to 95 q0, dehydration was stopped, cooled, and dissolved in a mixed solvent of methanol and toluene 2:1 to obtain a varnish with a resin concentration of 50%. Following the same treatment as in Example 1, a 1.6-wall thick laminate and a copper-clad laminate were obtained. Characteristic tests were conducted on the laminates obtained in the above Examples and Comparative Examples, and the results shown in Table 1 were obtained.

It will be appreciated that the method of the present invention significantly improves the properties of the laminate.

ship The method for the above characteristic test is as follows.

'11 Water absorption rate, insulation resistance, soldering heat resistance, and trichloride resistance were in accordance with JISC-6481.

[2' Punching workability was in accordance with ASTM ○-1 614-44.

'31 Dimensional change rate was determined by heating a test piece of 140 bars x 13 sides in length and inside at 100°C for 2 hours, then cooling to room temperature.

■ The warpage is 14 x 13 skin test pieces at 100oo.
After heating for a long time, the specimen was cooled to room temperature, and a straight edge was applied to the concave surface of the laminate, and the maximum distance (h) was determined as the warp of the test piece.

Claims (1)

[Claims] 1. Isopropenylphenol or an oligomer of isopropenylphenol represented by formula (II) or formula (III) alone or in a mixture and dehydrated castor oil are treated with an acidic catalyst in the presence or absence of a phenol. A method for producing a phenolic resin, which comprises reacting the resin with a phenol using an acidic catalyst, and then reacting the reaction product with formaldehyde as part of the phenol component. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In formula (II) and formula (III), n represents an integer from 0 to 18.)