JPH05116264A - Manufacture of phenol-resin laminated board - Google Patents

Abstract

PURPOSE:To obtain a laminated phenolic resin board having excellent curability and superior punchability, water resistance, electrical characteristics and mechanical characteristics by adding a resol type cresol-aldehyde resin to a drying-oil modified phenol-formaldehyde resin. CONSTITUTION:A novolak type cresol-aldehyde resin and aldehydes such as formalin, paraformaldehyde, etc., are reacted at a fixed temperature of 40-120 deg.C in the presence of a basic catalyst as an A component, and diluted with an organic solvent such as methanol, toluene, etc. Drying oil such as tung oil and phenols are reacted under an acid catalyst as a B component, and reacted with formaldehyde in the presence of the basic catalyst and changed into a resol. The 3-50 pts.wt. A component is added to the 100 pts.wt. B component.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a phenol resin laminate used for printed wiring boards, electrically insulating boards and the like.

[0002]

2. Description of the Related Art Recently, insulating materials, especially laminated plates and copper-clad laminated plates used for communication devices and electronic equipment, are punched at room temperature or at a relatively low temperature near room temperature from the viewpoint of automation of processing equipment and energy saving. Those with excellent workability are required. For this reason, a phenol / formaldehyde resin obtained by modifying various alkylphenols with phenol and modifying them with a drying oil is usually used as the resin for the laminate.

However, the phenol-formaldehyde resin modified with a drying oil has a slow curing rate due to the modification with a drying oil and the crosslink density is lowered, so that the resin in the laminated plate is apt to be insufficiently cured, and the heat resistance and the mechanical strength thereof are high. , Water resistance, etc. are deteriorated. Also, during punching, delamination and the like are likely to occur due to the low crosslink density. That is, since the conventional drying oil-phenols reaction product has a low number of moles of phenol added to the drying oil and produces a polymer of the drying oil, the reaction rate in the reaction with formaldehyde, that is, the resinification reaction and the curing reaction, is high. In addition, the curing speed was lowered, which was a cause of deterioration of various properties.

As a method for improving the curability, a method is proposed in which a reaction product obtained by reacting phenol and formaldehyde in the presence of an acid catalyst is added to a drying oil-modified phenol-formaldehyde resin (JP-A-61-21932). Has been done. Although a slight improvement in curability can be observed by this method, it is still insufficient in terms of punching workability, toughness, etc. with respect to the level recently demanded for laminated sheets.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a method for producing a phenol resin laminate having excellent curability, punching workability, water resistance, electrical properties and mechanical properties.

[0006]

The present invention uses a resin component obtained by adding the following component (A) to the following component (B) as the resin with which the base material for a laminated plate is impregnated. (A) Resol-type cresol-aldehyde obtained by reacting cresols and aldehydes in the presence of an acid catalyst to synthesize a novolak-type cresol-aldehyde resin, and further reacting it with an aldehyde in the presence of a basic catalyst Resin, (B) Dry oil modified phenol / formaldehyde resin.

The novolac type cresol-aldehyde resin is prepared by reacting a mixture of cresols, aldehydes and an acid catalyst at 60 to 150 ° C. for 30 minutes to 5 hours, or a mixture of cresols and an acid catalyst at 60 to 150 ° C. After the temperature is raised, aldehydes may be added dropwise over 15 minutes to 3 hours, and further reaction may be performed to synthesize the aldehydes. As the cresols, one or more selected from o-cresol, m-cresol and p-cresol is used, but it is preferable that the cresols contain 25% or more of m-cresol from the viewpoint of curability. If the m-cresol content is less than 25%, the curability will be slow. As the aldehydes, formaldehydes such as formalin, paraformaldehyde and trioxane, paraacetaldehyde, butyraldehyde, octylaldehyde, benzaldehyde and the like are used, and formalin and paraformaldehyde are particularly preferable. The reaction molar ratio of cresols and aldehydes when synthesizing a novolac type cresol-aldehyde resin varies depending on the aldehyde species, the catalyst species, the reaction temperature, and the reaction time. It is preferable to react from 1 to 1 mol. More preferably, it is 0.3 to 0.8.

The resole-type cresol-aldehyde resin is obtained by reacting the novolak-type cresol-aldehyde resin obtained by the above reaction with aldehydes such as formalin and paraformaldehyde at a predetermined temperature of 40 to 120 ° C. in the presence of a basic catalyst. After that, it is obtained by diluting with an organic solvent such as methanol or toluene. Alcohols such as methanol, ethanol, propanol and butanol, aromatic hydrocarbons such as benzene, toluene and xylene, and organic solvents such as ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone may be used as a reaction solvent. ..

The amount of aldehyde added is based on 1 mol of the cresols charged during the first step reaction, or when unreacted cresols are removed after the reaction, cresol in the reaction mixture after removal of unreacted cresols. 0.1 to 2.0 is preferable, and 0.6 to 1.4 is more preferable for 1 mol of the group. As the basic catalyst, ammonia, triethylamine, ethylenediamine, hexamethylenetetramine, amines such as triethanolamine, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, barium hydroxide and the like can be used. Ammonia and amines are preferably used because they do not leave ionic substances in the product.

The dry oil-modified phenol-formaldehyde resin can be synthesized, for example, by reacting a dry oil such as tung oil with a phenol with an acid catalyst, and further reacting formaldehyde with a basic catalyst in the presence of a resol.

The laminated sheet according to the present invention is prepared by dissolving the resol-type cresol-aldehyde resin obtained as described above in an organic solvent or by directly adding it to a drying oil-modified phenol-formaldehyde resin to form a varnish. Paper, linter paper, glass cloth glass non-woven cloth,
It can be obtained by impregnating and drying a base material such as a polyester fiber cloth, an aramid fiber cloth, and a sail cloth, and usually laminating 3 to 10 sheets and heating and pressing.

The amount of the resol-type cresol / aldehyde resin added to the dry oil-modified phenol / formaldehyde resin is preferably 3 to 50 parts by weight with respect to 100 parts by weight of the dry oil-modified phenol / formaldehyde resin,
More preferably, it is 10 to 35% by weight. If it is less than 3 parts by weight, there is almost no effect of improving the curability, and if it exceeds 50 parts by weight, the punching workability is deteriorated.

In the present invention, resins other than the components (A) and (B) may be blended within 50% of all resin components. Such resins include unmodified resole resins and alkylphenol resole resins.

[0014]

The phenolic resin laminate obtained by the present invention imparts highly reactive m-cresol and / or flexibility which is not combined with the drying oil to the resin component for varnish.
-It contains cresol and / or p-cresol, and is considered to have excellent curability due to its high reactivity and flexibility, and good punching processability, water resistance, electrical properties and mechanical properties. Be done. Further, the resole-type cresol-aldehyde resin used in the present invention is obtained by reacting a novolac-type cresol-aldehyde resin with aldehydes, and has a higher molecular weight than the resol-type cresol-aldehyde resin obtained by an ordinary synthesis method. It is thought that the curability is further improved.

[0015]

EXAMPLES The present invention will be described below with reference to examples.
“%” Indicates “% by weight”. (Synthesis example 1) m-cresol / p-cresol ratio is 60 /
A mixture of 3456 g of cresol mixture of 40, 1298 g of 37% formalin and 20 g of oxalic acid was reacted at 100 ° C. for 3 hours and then dehydrated under reduced pressure until the internal temperature reached 160 ° C. to synthesize a novolac type cresol-formaldehyde resin,
To this, 400 g of methanol was added and dissolved, and then 40 g of triethylamine and 650 g of 37% formalin were added to 80
After reacting at 0 ° C for 30 minutes, 1750 g of methanol was added and cooled to obtain a resol type cresol having a resin content of 51 wt%
5470 g of aldehyde resin (Resin 1) was obtained.

(Synthesis Example 2) A resin component 5 was prepared in the same manner as in Synthesis Example 1 except that a cresol mixture having an o-cresol / m-cresol / p-cresol ratio of 67/20/13 was used.
5490 g of 0 wt% resol type cresol aldehyde resin (resin 2) was obtained.

(Synthesis Example 3) 940 g of phenol, 37%
A mixture of 649 g of formalin and 2 g of 35% hydrochloric acid was reacted at reflux temperature for 4 hours, dehydrated under reduced pressure until the internal temperature reached 160 ° C, and dissolved in methanol to obtain a resin content of 50% by weight.
To obtain a phenol-formaldehyde resin (resin 3).

(Synthesis Example 4) 80 g of a mixture of 1200 g of phenol, 800 g of tung oil and 5 g of paratoluenesulfonic acid was used.
The reaction was carried out at ℃ for 3 hours. Then 800 g of toluene
After diluting and neutralizing by adding 20 g of triethanolamine, 500 g of paraformaldehyde and 30 g of 25% ammonia water are added, and the mixture is reacted at 90 to 100 ° C. for 4 hours, then dehydrated and detoluene under reduced pressure. 1000 g and 1000 g of methanol were added and diluted to obtain a tung oil-modified phenol-formaldehyde resin (resin 4) having a resin content of 50% by weight.

(Synthesis Example 5) Phenol 1000 g, 37
% Formalin 9800 g and triethylamine 20 g are mixed and reacted at 60 ° C. for 2 hours, then concentrated under reduced pressure and diluted with a mixed solvent of methanol / water = 80/20 to reduce the water content of the resin content of 50% by weight. A molecular phenol / formaldehyde resin (resin 5) was obtained.

Examples 1, 2 and Comparative Examples 1, 2 Kraft paper was impregnated with the resin 5 obtained in Synthesis Example 5 and dried to obtain a treated substrate having a resin content of 10.5%. Then, the treated base material was impregnated with the top coating varnish (resin 1 to resin 4) prepared separately according to the composition shown in Table 1 and dried to obtain a total resin content of 56%.
I got a prepreg of. 8 pieces of this are laminated and 35μ on one side
m copper foils were superposed and heated and pressed at 160 ° C. and 80 kg / cm ² for 60 minutes to obtain a phenol resin laminate having a thickness of 1.6 mm.

Table 1 shows the gelling time of each topcoat varnish on a 150 ° C. hot platen and the characteristics of the laminates obtained in Examples and Comparative Examples.

[Table 1]

[0022]

As is clear from the results shown in Table 1, the phenol resin laminate obtained by the production method of the present invention has excellent curability, punching workability, water resistance, electrical characteristics and mechanical characteristics. Therefore, it can be suitably used for a printed wiring board, an electrical insulating board, and the like.

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[Procedure amendment]

[Submission date] January 7, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0019

[Correction method] Change

[Correction content]

(Synthesis Example 5) Phenol 1000 g, 37
% Formalin 980 g and triethylamine 20 g are mixed and reacted at 60 ° C. for 2 hours, then concentrated under reduced pressure,
This was diluted with a mixed solvent of methanol / water = 80/20 to obtain a water-soluble low molecular weight phenol-formaldehyde resin (resin 5) having a resin content of 50% by weight.

Front page continuation (72) Inventor Mikio Ito 1-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Sumitomo Bakelite Co., Ltd.

Claims (3)

[Claims] 1. A method for producing a phenol resin laminate, which comprises impregnating and drying a resin component obtained by adding the following component (A) to the following component (B) into a substrate for a laminate, and forming the laminate. (A) Resol-type cresol-aldehyde obtained by reacting cresols and aldehydes in the presence of an acid catalyst to synthesize a novolak-type cresol-aldehyde resin, and further reacting this with an aldehyde in the presence of a basic catalyst Resin, (B) Dry oil modified phenol / formaldehyde resin. 2. The cresol of the component (A) contains 25% or more of m-cresol.
A method for producing a phenolic resin laminate as described. 3. The phenol resin laminate according to claim 1, wherein the amount of the component (A) added to the component (B) is 3 to 50 parts by weight with respect to 100 parts by weight of the component (B). Method of manufacturing a plate.