JPH0145416B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a laminate or a copper-clad laminate. Conventionally, when manufacturing phenolic resin laminates or copper-clad laminates, a varnish made by diluting resol-type phenolic resin with an organic solvent such as methanol, acetone, toluene, or methyl ethyl ketone was used.
After impregnating a base material for a laminate such as linter paper or kraft paper, the organic solvent is volatilized and dried in a hot air circulation drying oven. Therefore, a large amount of organic solvent is required, and energy costs for volatilization and drying of the organic solvent and waste gas treatment costs are required. Additionally, the solvent was flammable, creating a dangerous work environment. An object of the present invention is to provide a method for manufacturing a laminate or copper-clad laminate that eliminates the above-mentioned conventional drawbacks and streamlines the manufacturing process by reducing the use of solvents and drying steps. do. In order to achieve the above object, the present invention applies a resin composition consisting of a drying oil-modified novolak type phenolic resin and hexamethylenetetramine in a heated molten state to a cellulose paper base material impregnated with a phenolic resin initial condensate. , is characterized in that a plurality of sheets of this base material are superimposed and molded under heat and pressure. Further, a copper foil is placed on at least one surface of the stacked base materials and then heated and press-molded. The phenolic resin initial condensate used in the present invention is
1~ obtained by reacting phenols and formaldehydes under a basic catalyst represented by a metal alkali such as caustic soda, caustic potash, or barium hydroxide, or an amine compound such as trimethylamine, triethylamine, dimethylamine, or diethylamine.
It is an initial condensate of dinuclear bodies. When this initial condensate is impregnated into a cellulose paper base material such as linter paper or kraft paper, it penetrates into the interior of the base material due to its hydrophilic properties. The drying oil-modified novolak type phenolic resin used in the present invention can be obtained by reacting formaldehyde with a drying oil-phenol adduct obtained by reacting phenols and drying oil in the presence of an acidic catalyst, or by reacting formaldehyde with a drying oil-phenol adduct obtained by reacting phenols and drying oil in the presence of an acidic catalyst. It is obtained by reacting a novolak-type phenolic resin obtained by reacting the above in the presence of an acidic catalyst with a drying oil. The softening point of the drying oil-modified novolac type phenolic resin is preferably 100°C or lower in order to prevent gelation during the process of applying it to a base material in a heated molten state. In the present invention, hexamethylenetetramine is added as a curing agent to the drying oil-modified novolak type phenolic resin, and the appropriate amount is 3 to 15 parts by weight per 100 parts by weight of the drying oil-modified novolak type phenolic resin. . When applying to the substrate, the heating melting temperature of the dry oil-modified novolac type phenolic resin-hexamethylenetetramine mixed composition is 110
Desirably below ℃. Example 0.5 g of paratoluenesulfonic acid was added to 680 g of phenol and 350 g of tung oil, and the mixture was reacted at 80 to 85°C for 120 minutes. Then, 195 g of 85% paraformaldehyde was added, and the mixture was reacted at 70 to 75°C for 150 minutes. After dehydration under reduced pressure, a tung oil-modified novolak type phenolic resin with a softening point of 65°C was obtained. The obtained tung oil-modified novolak type phenolic resin was heated and melted at 85°C, and 10 parts by weight of hexamethylenetetramine was added to 100 parts by weight of the tung oil-modified novolak type phenolic resin and mixed with stirring. The condensate was applied to dry kraft paper impregnated with 10% by weight.
The resin adhesion amount of the obtained coated paper was 52% by weight. A composition consisting of 8 sheets of the above coated paper and a 35μ thick copper foil layered on one side of the paper was heated at a pressure of 110Kg/cm ² and a temperature of 170℃.
A copper-clad laminate was obtained by molding for 55 minutes. Comparative example Add 0.5 g of paratoluenesulfonic acid and 50 g of methanol to 680 g of phenol and 350 g of tung oil, and add 80 to 85 g.
After reacting for 120 minutes at °C, add 25% ammonia water.
20g, add 250g of 85% paraformaldehyde
The reaction was carried out at 80-85°C for 270 minutes. Next, the mixture was dehydrated under reduced pressure and diluted with toluene to obtain a tung oil modified phenolic resin varnish having a resin concentration of 50% by weight. Kraft paper, which had been previously impregnated with 10% by weight of a phenolic resin initial condensate and dried, was impregnated with the tung oil-modified phenolic resin varnish and dried to obtain coated paper with a resin adhesion of 51% by weight. A composition consisting of 8 sheets of the above coated paper and a 35μ thick copper foil layered on one side of the paper was heated at a pressure of 110Kg/cm ² and a temperature of 170℃.
A copper-clad laminate was obtained by molding for 55 minutes. Table 1 shows the performance of the copper-clad laminates of Examples and Comparative Examples.

[Table] As is clear from Table 1, the performance of the copper-clad laminate according to the present invention is that the heat shrinkage rate is smaller than that of the copper-clad laminate manufactured using conventional methods, and the performance of the copper-clad laminate according to the present invention is lower in terms of bending strength, insulation resistance, water absorption, and The punching workability is the same. Note that a laminate without copper foil attached has the same performance as the above example. According to the present invention, no solvent is used in the coating process of the drying oil-modified phenolic resin, and the coating is carried out in a heated molten state, thereby eliminating the need for a drying process. Additionally, energy costs and waste gas treatment costs can be reduced accordingly. Furthermore, unlike conventional resol-type resins, novolac-type resins are used, so there is less curing shrinkage and volatile matter generation during the curing process, resulting in copper-clad laminates and laminates with less dimensional change, warping, and twisting due to heating. can get.

Claims (1)

[Scope of Claims] 1. A resin composition consisting of a dry oil-modified novolac type phenolic resin and hexamethylenetetramine is applied in a heated molten state to a cellulose paper base impregnated with a phenolic resin initial condensate, and this base material 1. A method for producing a copper-clad laminate, which comprises stacking a plurality of sheets of the above, further placing copper foil on at least one surface, and molding under heat and pressure. 2. A resin composition consisting of a dry oil-modified novolak type phenolic resin and hexamethylenetetramine is applied in a heated molten state to a cellulose paper base material impregnated with a phenolic resin initial condensate, and multiple sheets of this base material are stacked together. A method for producing a laminate, which is characterized by heating and pressure forming.