JPH06107756A - Production of modified phenol resin - Google Patents

Abstract

PURPOSE:To obtain a modified phenol resin having excellent low-temperature punchability, electrical insulating properties and electrolytic corrosion. CONSTITUTION:A tung oil is reacted with a phenol in the presence of a solid acid catalyst to synthesize a vegetable oil to which the phenol is added and after the reaction is completed, the solid acid catalyst is removed by filtration. The reaction solution from which the catalyst is removed is reacted with a phenol and an aldehyde in the presence of a basic catalyst into a resole.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a vegetable oil-modified phenol used for paper-phenol laminates and copper-clad laminates (both are collectively referred to as laminates) having excellent low-temperature punchability and electrical characteristics. The present invention relates to a method for producing a resin.

[0002]

2. Description of the Related Art Conventionally, a paper-phenol laminated plate has been punched or contoured by punching with a die. In recent years, in order to reduce the dimensional change of printed wiring boards, there is a tendency to punch at room temperature without heating. Therefore, a flexible phenol resin has been used in order to improve the punching workability of the laminated plate. Furthermore, with the development of electronic devices, printed wiring boards tend to have higher densities. Phenolic resin laminated board is also following the flow,
Demand for double-sided printed wiring boards using silver through-holes is growing rapidly. Therefore, recently, punching workability and high electrical characteristics have been required. As a method for making the phenol resin flexible, generally, phosphoric acid esters mainly containing eleostearic acid and having a high reactivity, such as tung oil and triphenyl phosphate, are heavily used. However, tung oil is not used as it is, and tung oil is reacted with phenols in the presence of a strongly acidic catalyst to use modified tung oil in which phenols are added. In addition, the flexibility of phosphoric acid esters, etc.
There is a problem with the solvent resistance and electrical characteristics of the laminate, and it has been difficult to achieve low-temperature punching workability only with phosphoric acid esters.

[0003]

The reaction of tung oil or cashew oil with phenols uses a reaction product obtained by adding phenols to vegetable oil with a phenol resin by using a strongly acidic substance such as paratoluenesulfonic acid as a catalyst. Although it is generally used as a modifier for the above, the strongly acidic catalyst used in this reaction acts to reduce the electrical characteristics of the laminated plate that could remain in the varnish. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for producing a modified phenolic resin having excellent electrical characteristics and low-temperature punching processability.

[0004]

[Means for Solving the Problems] As described above, a strongly acidic catalyst such as paratoluenesulfonic acid forms a salt with the basic substance of the resolization catalyst in the tung oil-modified phenolic resin and remains in the form of a salt. It is thought that These salts cause the deterioration of electrical insulation and electrolytic corrosion resistance when used as a printed wiring board. Therefore, in the reaction with highly reactive vegetable oil such as tung oil containing a large amount of phenol and eleostearic acid, a solid acid catalyst is reacted by using a catalyst that does not dissolve in the reaction solution, that is, a solid acid, and a solid acid catalyst is obtained by filtering after completion of the reaction. By removing it outside the system, impurities in the vegetable oil-modified phenol resin can be reduced.

Vegetable oil-modified phenolic resins such as tung oil are obtained by reacting tung oils with phenols as described above, with or without addition of phenols, and by adding formaldehyde and a basic catalyst. It can be synthesized by performing a resolization reaction. It has been found that when a wood base material is impregnated with this tung oil-modified phenolic resin and compression-molded into a laminate, the electrical performance of the conventional laminate can be further improved without lowering the electrical characteristics and electrolytic corrosion resistance.

The highly reactive vegetable oils used in the present invention include tung oil and cashew oil, and tung oil having a high degree of unsaturation is particularly preferable. Examples of phenols include phenol, orthocresol, metacresol, paracresol, xylenol, catechol, resorcin, hydroquinone, octylphenol, tert-butylphenol, nonylphenol and bisphenol-A. Examples of solid acids used as catalysts for the reaction of vegetable oils with phenols include perfluoroalkanesulfonic acid type ion exchange resins, benzenesulfonic acid type ion exchange resins and synthetic zeolites. A benzenesulfonic acid type ion exchange resin that is easy to handle and relatively inexpensive is preferable.

The blending ratio of vegetable oil and phenols is not particularly limited, but from the characteristics of the laminated plate, vegetable oil: phenols = 2: 8 to 6: 4, particularly 3: 7 to 4: 6 is preferable. When the blending ratio of vegetable oil is more than 6: 4, the curability of the laminated plate is lowered and defects such as sticky surface appear. On the other hand, if it is less than 2: 8, the low temperature punching workability of the laminated sheet cannot be satisfied. Further, the addition amount of the solid acid catalyst is not particularly limited, but the addition amount is a property which should be decided depending on the surface area and the functional group density of the solid acid, but the particle size is 2 m.
If the ion-exchange resin is a pellet of m and has a functional group density (3.7 meq / g-dry resin), it is preferably 0.1 to 30 parts, especially 1 to 10 parts per 100 parts by weight of vegetable oil. If it is less than 0.1 part, the reaction becomes slow and the industrial productivity is lowered. When it is 30 parts or more, the viscosity of the reaction system increases and the stirring efficiency decreases, which is not practical. The reaction of tung oils with phenols can be carried out without solvent or in solvent, but it is preferable to carry out the reaction without solvent in consideration of the following reaction with formaldehyde. The reaction temperature is 50 to 250 ° C., especially
It is preferably 100 ° C or lower. When the temperature is 100 ° C. or higher, hydrolysis reaction frequently occurs, lowering the molecular weight is apt to occur, and eventually the characteristics of the laminated plate are deteriorated.

After the reaction of tung oils and phenols is completed, the solid acid catalyst used in the reaction is removed, but the method is not particularly limited. Any method used in ordinary chemical industries can be applied. For example, fine mesh mesh made of stainless steel, nylon, Teflon, polyester woven cloth or cotton cloth is tightly tied to the outlet of the reaction kettle and filtered under normal pressure, or by using filter paper or glass filter paper. Alternatively, there is a method of filtering under reduced pressure. In some cases, phenol is added to the reaction solution thus obtained, formaldehyde and a basic catalyst are added, and a usual resolization reaction is performed to synthesize a resin for a laminate. In some cases, a flame retardant may be added to give a flame-retardant laminate resin. A paper base material is impregnated with the varnish thus obtained, and dried by heating to prepare a prepreg. A predetermined number of these are stacked, a copper foil with an adhesive is stacked on one surface, and pressure-heated at a predetermined pressure and temperature for a predetermined time to produce a copper-clad laminate. Hereinafter, the present invention will be specifically described with reference to examples.

[0009]

【Example】

Example 1 (Synthesis example 1 of varnish for laminated board) 200 g of tung oil and 20 phenol in a three-necked flask of 21 equipped with a thermometer and a cooling tube.
0 g, sulfonated styrene type ion exchange resin (Organo brand name: Amberlyst 200 (exchange capacity 4.3 m
eq / g-dry resin) was added and reacted at 120 ° C for 3 hours. After completion of the reaction, the ion exchange resin was removed by filtration with a 100-mesh cotton cloth under normal pressure. Further, 180 g of phenol, 255 g of paraform, 80 g of methanol and 38 g of aqueous ammonia were added to this reaction solution, and a resolization reaction was carried out at 80 ° C. When the gelation time at 160 ° C. reached 6 minutes, the mixture was heated under reduced pressure and dehydrated and concentrated. When the gelling time reached 3 minutes, the reaction was terminated and 200 g of toluene and 200 g of methanol were added to form a varnish 1.

Example 2 (Synthesis example 2 of varnish for laminated plate) 200 g of tung oil, 250 g of m, p-cresol and the ion exchange resin used in Example 1 were washed in the same flask as in Example 1, washed and dried, Add 20 g of ion exchange resin regenerated by treatment with nitric acid,
The reaction was carried out at 00 ° C for 2 hours. Further, 50 g of xylene resin (trade name: Nikanol-H, manufactured by Mitsubishi Gas Chemical Co., Inc.) was added and reacted at the same temperature for 1 hour. After the reaction was completed, it was filtered under reduced pressure using a glass filter. The filtrate was returned to the flask again, and 100 g of phenol, 177 g of paraform, 60 g of methanol, 21.6 ammonia water were further added.
g was added and a resolization reaction was carried out at 80 ° C. When the gelation time at 160 ° C. reached 6 minutes, the mixture was heated under reduced pressure and dehydrated and concentrated. When the gelation time reached 3 minutes, the reaction was terminated and 200 g of toluene and 200 g of methanol were added.
Varnish 2 was prepared by adding g.

Example 3 (Synthesis example 3 of varnish for laminated plate) In a flask similar to that of Example 1, 200 g of phenol, 50 g of xylene resin (trade name: Nikanol-H, manufactured by Mitsubishi Gas Chemical Co., Inc.), and perfluoroalkane having a particle diameter of 2 mm were used. 50 g of a sulfonic acid type ion exchange resin was charged and reacted at 100 ° C. for 1 hour. And tung oil 2
00 g was added and the reaction was carried out at the same temperature for 5 hours. After the reaction was completed, the ion exchange resin was filtered and removed from the flask out of the system. 180g phenol and 255 paraform in the filtrate
g, 80 g of methanol, 38 g of ammonia water were added to obtain 8
A resolization reaction was performed at 0 ° C. When the gelation time at 160 ° C. reached 6 minutes, the mixture was heated under reduced pressure and dehydrated and concentrated. When the gelation time reached 3 minutes, the reaction was terminated and 200 g of toluene and 200 g of methanol were added to form a varnish 3.

Comparative Example 1 (Synthesis of tung oil-modified phenolic resin) A flask similar to that of Example 1 was charged with 200 g of phenol, 50 g of xylene resin (trade name: Nikanol-H, manufactured by Mitsubishi Gas Chemical Co., Inc.), and 0.3 g of paratoluenesulfonic acid. And reacted at 100 ° C. for 1 hour. To this, 200 g of tung oil was added and reacted at the same temperature for 2 hours. After completion of the reaction, phenol 180 g, paraform 255 g, methanol 80 g, ammonia water 38
g was added and a resolization reaction was carried out at 80 ° C. When the gelation time at 160 ° C. reached 6 minutes, the mixture was heated under reduced pressure and dehydrated and concentrated. When the gelation time reached 3 minutes, the reaction was terminated and 200 g of toluene and 200 g of methanol were added.
Comparative varnish 1 was prepared by adding g.

As described above, 4 kinds of the synthesized varnishes are used as resin components.
%, The kraft paper which was first impregnated with the aqueous solution phenol resin was impregnated and dried to prepare a vegetable oil modified phenol resin prepreg. A predetermined number of the prepregs are stacked, and a copper foil with an adhesive is stacked on one side to obtain 100 kg / c.
A copper-clad laminate was manufactured by heating at m ² at 160 ° C. for 1 hour. The characteristics of the laminated plate were measured according to JIS-6481. The results are shown in Table 1.

[0014]

[Table 1]

[0015]

As is apparent from Table 1, according to the present invention, the insulation resistance after immersion in boiling water and absorption of moisture is significantly improved, as compared with the tung oil-modified phenol resin synthesized by the conventional method. Further, the electrolytic corrosion resistance was also greatly improved without the occurrence of dentrite even after 1000 hours.

Claims (2)

[Claims] 1. A reaction product obtained by reacting a drying oil containing eleostearic acid as a main component with a phenol as a solid acid catalyst and removing the solid acid by filtration after the reaction is completed in the presence of a basic catalyst. A process for producing a modified phenolic resin, which comprises adding an aldehyde to a resin to form a resole. 2. The method for producing a modified phenolic resin according to claim 1, wherein the solid acid is a perfluoroalkanesulfonic acid type ion exchange resin, a sulfone type strongly acidic ion exchange resin or a synthetic zeolite.