JPH09157414A - Production of phenol resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a phenol resin, excellent in punchability and capable of providing a paper phenol laminated sheet excellent in water resistance and electrical insulating properties by reacting a (semi)drying oil with phenol in the presence of formaldehyde and an acidic catalyst. SOLUTION: (C) A (semi)drying oil (e.g. tung oil) is reacted with (B) phenols (e.g. phenol) in the presence of (A) formaldehyde and (B) an acidic catalyst (e.g. p-toluenesulfonic acid) and then converted into a resol in the presence of (E) an alkaline catalyst (e.g. triethylamine). For example, the amount of the component (C) used is 10-30% based on the component (D) and the molar ratio of the component (A) to the component (D) is within the range of 0.1-0.5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed wiring board for a consumer electronic device, a paper substrate phenolic resin laminate (hereinafter
The present invention provides a method for producing a phenolic resin used for a paper phenolic laminate).

[0002]

2. Description of the Related Art Conventionally, as a method for improving the punching workability of a paper phenol laminated sheet, a drying oil such as tung oil, cashew oil, linseed oil, castor oil, linolenic oil, linole oil, epoxidized vegetable oil, and a semi-drying oil. Etc. and phenols, phenols such as cresol, are reacted under an acidic catalyst, and then an oil-modified phenolic resin resolized with an alkaline catalyst is used, and a method of using an external plasticizer that is not involved in the curing of the phenolic resin Was also done. But,
Even if an oil-modified phenolic resin is used, it is necessary to increase the usage rate of (semi) drying oil in order to obtain sufficient punching workability, and the heat resistance, water resistance, moisture resistance, and electrical insulation of laminated boards However, it is disadvantageous in terms of cost. Similarly, when an external plasticizer is added, the heat resistance, water resistance, moisture resistance, and electric insulation of the laminated plate will also decrease.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a method for producing a phenolic resin, which is capable of obtaining a laminate having excellent punching workability, water absorbency and electrical insulation.

[0004]

According to the present invention, when synthesizing an oil-modified phenolic resin, a (semi) drying oil and a phenol are reacted in the presence of formaldehyde in the presence of formaldehyde under an acid catalyst. It is a method for producing a phenol resin, which is characterized in that it is carried out. According to the method of the present invention, phenols are condensed with formaldehyde to be polymerized with a methylene group (novolak),
Since the punching workability is improved and the methylol groups at the time of resolization are reduced, a laminate having excellent water absorption and electrical insulation can be obtained.

Oils used in oil-modified phenolic resins include tung oil, cashew oil, linseed oil, castor oil, linolenic oil, linole oil, epoxidized vegetable oil and other drying oils, and semi-drying oils. Desirable in terms of reactivity and cost. The amount of dry oil used is 5% with respect to phenols
About 50% is desirable. Particularly preferably 10% to 30
%. If it is less than 5%, the flexibility is not sufficient, and if it exceeds 30%, the reactivity and adhesion are deteriorated.

Examples of the acid catalyst include oxalic acid, p-toluenesulfonic acid, hydrochloric acid and sulfuric acid. As the phenols, phenol, cresol, tert-butylphenol, octylphenol, nonylphenol and the like are used alone or in combination. Formaldehyde added when reacting oil and phenols with an acid catalyst is formalin aqueous solution, paraformaldehyde, etc., and the molar ratio of formaldehyde to phenols is preferably in the range of 0.1 to 0.5. If it is less than 0.1, no sufficient effect can be obtained, and if it exceeds 0.5, the molecular weight becomes too high and resolization becomes difficult.

The formaldehyde added at the time of resolization is preferably in the range of 0.8 to 2.0 in molar ratio with respect to the phenols together with the formaldehyde added under the acid catalyst. When it is less than 0.8, unreacted phenol component increases, and when it exceeds 2.0, unreacted formaldehyde remains in a large amount and the odor is strong, which is also disadvantageous in terms of cost. As the alkaline catalyst, tertiary amines such as triethylamine and triethanolamine are particularly suitable, but aqueous ammonia, hexamethylenetetramine and the like can also be used.

The oil-phenolic resin obtained by the above method is impregnated into a paper base material by a conventional method, a plurality of the obtained resin-impregnated papers are superposed and heat-pressed to obtain punching workability. An excellent paper-phenolic laminate can be obtained. The oil-modified phenolic resin obtained in the present invention can be applied to both a two-stage impregnation method in which a paper base material is subjected to a primary impregnation treatment and then a secondary impregnation treatment, and a one-stage impregnation method without a primary impregnation treatment. it can.

[0009]

The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples.

[Synthesis of Low-Molecular Weight Phenolic Resin (Varnish d)] A mixture of 1000 g of phenol, 980 g of 37% aqueous formaldehyde and 20 g of triethylamine was reacted at 60 ° C. for 2 hours and then concentrated under reduced pressure, which was then concentrated with methanol. Diluted to obtain a phenol resin varnish d having a resin content of 50%.

Example 1 Synthesis of Oil-Modified Phenolic Resin (Varnish a) and Production of Laminate A Using the Same 1600 g of phenol, 800 g of tung oil and 390 g of 40% formalin aqueous solution in the presence of paratoluenesulfonic acid.
The reaction was carried out at 95 ° C for 2 hours. Next, paraformaldehyde 500g, triethylamine 30g, toluene 200
After adding 0 g and reacting at 90 ° C. for 2 hours, the mixture was concentrated under reduced pressure,
This was diluted with a mixed solvent of toluene and methanol to obtain an oil-modified phenol resin varnish a having a resin content of 50%. Varnish a 100 parts by weight, varnish d 40 parts by weight, brominated epoxy resin (resin content 50%) 20 parts by weight, methylolated melamine resin (resin content 50%) 20 parts by weight, triphenyl phosphate 10 parts by weight resin varnish 55%
A prepreg was obtained by impregnating a paper base material so that Eight pieces of this prepreg and copper foil with adhesive on both front and back sides are laminated and heat-pressed to form a laminate A having a thickness of 1.6 mm.
I got

Example 2 Synthesis of Oil-Modified Phenolic Resin (Varnish b) and Preparation of Laminated Board B Using the Same B. Cresol 1600 g, tung oil 800 g, paraformaldehyde 50 g, and toluene solvent 1000 g in the presence of paratoluenesulfonic acid. And reacted at 95 ° C for 2 hours. Next, 600 g of paraformaldehyde, 20 g of triethylamine, and 1000 g of toluene were added and reacted at 90 ° C. for 2 hours, then concentrated under reduced pressure and diluted with a mixed solvent of toluene and methanol to dilute the oil-modified cresol resin varnish b having a resin content of 50%. Got Varnish b100 parts by weight, varnish c4
0 parts by weight, brominated epoxy resin (resin content 50%) 20 parts by weight, methylolated melamine resin (resin content 50%) 20
The paper base material was impregnated with a varnish containing 10 parts by weight of triphenyl phosphate and 50 parts by weight of triphenyl phosphate to obtain a prepreg. Eight prepregs and copper foil with an adhesive were superimposed on both front and back surfaces thereof, and heated and pressed to obtain a laminate B having a thickness of 1.6 mm.

Comparative Example 1 Synthesis of Oil-Modified Phenolic Resin (Varnish c) and Preparation of Laminate C Using the Same 1600 g of phenol and 800 g of tung oil were reacted at 95 ° C. for 2 hours in the presence of paratoluenesulfonic acid. . Then 650 g of paraformaldehyde, 30 of triethylamine
g and 2000 g of toluene were added, and the mixture was reacted at 90 ° C. for 2 hours, concentrated under reduced pressure, and diluted with a mixed solvent of toluene and methanol to obtain an oil-modified phenol resin varnish b having a resin content of 50%. 100 parts by weight of varnish c, d40 of varnish
Parts by weight, 20 parts by weight of brominated epoxy resin (resin content 50%), 20 parts by weight of methylolated melamine resin (resin content 50%), and 10 parts by weight of triphenyl phosphate so that the varnish has a resin content of 55%. A paper base material was impregnated to obtain a prepreg. Eight sheets of the prepreg and copper foil with an adhesive were superimposed on both front and rear surfaces thereof, and heated and pressed to obtain a laminate C having a thickness of 1.6 mm.

The characteristics of each laminate obtained by the above method were measured and the results shown in Table 1 were obtained.

[Table 1]

[0015]

As is clear from the above results, by using the phenol resin obtained by the method of the present invention, it is possible to obtain a paper phenol laminate excellent in punching workability, water resistance and electric insulation. You can

Claims (2)

[Claims] 1. When synthesizing a drying oil or a semi-drying oil modified phenolic resin, the drying oil or the semi-drying oil and the phenols are reacted with an acid catalyst in the presence of formaldehyde, and then the resolization is performed with an alkali catalyst. A method for producing a phenol resin, which is characterized by carrying out. 2. A method for producing a paper-based phenolic resin laminate, which comprises using the phenolic resin obtained in claim 1.