JPS6051498B2 - Manufacturing method of laminates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a laminate or a metal foil-clad laminate having excellent electrical performance and punching workability.

Epoxy resins and oil-soluble phenol resins are used for laminates and metal foil laminates for electronic devices, as more advanced electrical performance and punching workability are required as electronic devices become smaller and lighter. Widely used.

However, epoxy resins and oil-soluble phenolic resins have poor impregnation properties into paper base materials, and to improve this, the paper base material is impregnated with a low condensate such as polymethylolphenol or polymethylolmelamine in advance, dried, and then Conventionally, a two-step coating method is used in which resin is impregnated and dried. Therefore, working efficiency is poor and costs are high, and punching workability cannot be sufficiently improved in terms of properties.

The present invention aims to solve the above-mentioned problems,
Regarding the production of paper-based laminates or metal foil-clad laminates having excellent electrical performance and punching workability by a method other than pretreatment with a low condensate of polymethylolphenol or polymethylolmelamine. We conducted a thorough study.

That is, in the present invention, a paper base material is pretreated with a monohydric alcohol having a boiling point of 90 to 135°C or a mixture of the alcohol and water, and then impregnated with an epoxy resin or an oil-soluble phenol resin, dried, and then laminated and formed. It is characterized by

In the present invention, pretreatment refers to, for example, isopropanol (
This is a process in which a paper base material is impregnated with a paper base material (boiling point: 97.3°C) or an aqueous solution thereof, and the base fibers are swollen to improve the impregnability of the epoxy resin or oil-soluble phenol resin. The mixture with alcohol or water used for pretreatment is used to remove other unnecessary components such as condensed water remaining in the resin and unsaturated water when the epoxy resin or oil-soluble phenol resin is impregnated and dried at 130°C or higher. Easily dispersed with low molecular weight reactants. The epoxy resin used in the present invention is a common epoxy resin obtained by condensation of epichlorohydrin and bisphenols.

In addition, the oil-soluble phenol resin is a 100% phenol resin of 1p-alkylphenol and formalin condensation, 2
These include drying oil-modified phenolic resins such as tung oil and linseed oil, and natural resin-modified phenolic resins such as 3-rosin and copal. The present invention will be explained below with reference to Examples.

Example 110 parts by weight of phenol, 22 parts by weight of xylene resin, and 0.1 part by weight of balatoluenesulfonic acid were reacted at 100°C for 6 minutes, and 6 parts by weight of Chinese tung oil was added thereto to further react 10 parts by weight.
The reaction was carried out at 0'C for 12 minutes.

This reaction product contains 3 parts of phenol and 5 parts of 85% paraform.
1 part by weight, 8 parts by weight of 25% ammonia, and 1113 parts by weight of toluene/methanol were added, and the mixture was reacted at 95°C for 360 minutes, and then concentrated under reduced pressure to give 1 part of toluene/methanol.
A mixed solvent of No. 12 was added to obtain a tung oil-modified phenolic resin varnish with a nonvolatile content of 50% (varnish A). On the other hand, 10 parts by weight of phenol, 200 parts by weight of 37% formali, and 3 parts by weight of trimethylamine were subjected to a powder reaction at 60°C, concentrated under reduced pressure, and methanol was added to obtain a water-soluble phenolic resin varnish with a nonvolatile content of 50%. (varnish B).

A mixed solution of isopropanol/water/=2 was sprayed onto kraft paper at a rate of 150 g/I, and air-dried for 5 minutes at room temperature.

The pretreated kraft paper was impregnated with a mixed varnish consisting of 1 part of varnish AlO and 1 part of varnish B, and then dried at 130°C or higher to produce coated paper with a resin content of 50%. The coated paper 8
A composition consisting of a copper foil layered with a 35μ thick adhesive on one surface was heated and pressed at 160°C at 1,100kg/d for 5 minutes to achieve 1.6TI0! A copper-clad laminate with a thickness of l was obtained* (invention product 1).

The performance test results are shown in Table 1. Comparative Example 1 Kraft paper was pretreated in the same manner as in Example 1 using a mixture of methanol (boiling point 65°C)/water = 3.

The kraft paper was impregnated with the same mixed varnish as in Example 1 and dried to obtain a 1.6 mm thick copper-clad laminate under the same conditions (
Comparison product 1). The performance test results are shown in Table 1. Comparative Example 2: Using kraft paper without pre-treatment, other conditions are as in Example 1
A copper-clad laminate with a thickness of 1.6wrIn was obtained in the same manner as (
Comparison product 2).

The performance test results are shown in Table 1. Example 2 An epoxy resin varnish containing 100 parts by weight of an epoxy resin (epoxy equivalent: 520), 3 parts by weight of methylnaziktan hydride, and 0.5 parts by weight of benzyldimethylamine (
Varnish C) was prepared.

A mixed solution of isopropanol/water = 2 ha was sprayed onto the kraft paper at a rate of 150 g/d, and the paper was air-dried at room temperature for 5 minutes. After impregnating the pretreated kraft paper with varnish C 13
It was dried at 0° C. or higher to produce coated paper with a resin content of 53%.
Using the coated paper, the lamination molding process was carried out in the same manner as in Example 1 to obtain a copper-clad laminate having a thickness of 1.6 mg (Product 2 of the present invention). Comparative Example 3: Using kraft paper without pre-treatment, other conditions are as in Example 2
Similarly, 1.6Tr0! A copper-clad laminate having a thickness of L was obtained (Comparative Example 3).

As mentioned above, in the present invention, the paper base material is pretreated with a monohydric alcohol having a boiling point of 90 to 135°C or a mixture of the alcohol and water, so that the impregnation of the base resin into the paper base material is improved. The properties of epoxy resins or oil-soluble phenol resins, which conventionally had excellent properties but poor impregnation into paper base materials, can be fully exhibited, and a laminate with excellent electrical performance and punching workability can be obtained.

Further, since two-step coating as in the conventional method is not performed, workability can be improved, implementation is easy, and manufacturing costs can be reduced. Comparative Example 1 shows that if low boiling point alcohol is used for pretreatment, rapid volatilization occurs when the coated paper dries, making it impossible to swell the base material sufficiently and being ineffective. Obviously, when an alcohol with a high boiling point is used, it is disadvantageous because the alcohol does not scatter during the drying process of the coated paper and remains in the coated paper.

Claims (1)

[Claims] 1. A paper base material is pretreated with a monohydric alcohol having a boiling point of 90 to 135°C or a mixture of the alcohol and water, and then impregnated with an epoxy resin or an oil-soluble phenol resin, dried, and then laminated and molded. A method for producing a laminate or a metal foil-clad laminate.