JP2787846B2 - Printed circuit laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated board for a printed circuit used particularly for electric equipment, electronic equipment, communication equipment and the like.

[0002]

2. Description of the Related Art As consumer electronic devices and industrial electronic devices are becoming smaller and more sophisticated, circuit boards to which a high voltage is applied, such as computers and measuring instruments, require heavy objects such as transformers and transistors. Therefore, a thermosetting resin glass woven laminate is used because of its strength. Furthermore,
In addition to this, a substrate having excellent tracking resistance has been required from the standpoint of ensuring safety in order to increase the density. Conventionally, in a phenolic resin laminate used for consumer equipment, a melamine resin, an alicyclic epoxy resin or a polyester resin, which hardly carbonizes, is used as an adhesive used for bonding a metal foil because of the tracking resistance. Was. On the other hand, epoxy laminates such as composite laminates tend to be thinner with miniaturization and higher density, so it is difficult to apply an adhesive to the metal foil, or the metal foil becomes The metal foil with the adhesive cannot be used due to curling or the like. On the other hand, for industrial equipment, an alicyclic epoxy resin or a resin having a small number of aromatic rings, such as an unsaturated polyester resin, has been used to improve tracking resistance. There were problems such as insufficient strength and weak peeling strength with the metal foil.

[0003]

SUMMARY OF THE INVENTION The present invention has been completed as a result of various studies in order to solve the above-mentioned problems. In view of the fact that brominated epoxy resins are extremely easy to carbonize, the surface layer Non-brominated epoxy resin glass woven fabric containing inorganic filler is arranged, and the middle layer is made of brominated epoxy resin containing inorganic filler for imparting flame resistance, which degrades electrical and other properties And to provide a printed circuit board having excellent tracking resistance.

[0004]

According to the present invention, a resin for a surface layer is constituted by an epoxy resin containing no bromine, and
Aluminum hydroxide as the inorganic filler resin of the surface layer 1
An epoxy resin glass woven fabric containing 10 to 200 parts by weight with respect to 00 parts by weight, more preferably, the intermediate layer is mainly composed of a brominated epoxy resin, and
A printed circuit laminate, comprising 10 to 200 parts by weight of an inorganic filler with respect to 0 parts by weight. In the present invention, aluminum hydroxide is a hydrated alcohol.
It also includes Mina. In the present invention, aluminum hydroxide used for the surface layer is contained in an amount of 10 to 200 parts by weight, preferably 20 to 150 parts by weight, based on 100 parts by weight of the resin. If the surface layer is formed only of a non-brominated epoxy resin without containing any aluminum hydroxide, the effect on tracking resistance is low, and the same applies even when the content of aluminum hydroxide is less than 10 parts by weight. If the amount exceeds 200 parts by weight, the resin viscosity at the time of mixing the aluminum hydroxide becomes too high, so that it becomes difficult to impregnate the glass woven fabric, and both are not preferable.

In the present invention, hydroxylic acid is used as an inorganic filler.
Aluminum is preferred over flame retardancy, workability and flame resistance
Used properly. Further, when aluminum hydroxide is used for the surface layer, the effect of improving the tracking resistance is great. In the present invention, while the tracking resistance is improved by configuring the surface layer as described above, aluminum hydroxide enters between the filaments of the glass woven fabric while maintaining the solder heat resistance and the copper foil peeling strength. Thereby, the surface roughness can be improved. On the other hand, the intermediate layer uses a brominated epoxy resin as a main component as an epoxy resin, and uses an inorganic filler in an amount of 10 to 2 parts by weight based on 100 parts by weight of the resin.
By using 00 parts by weight, flame retardancy and workability can be improved. If the amount of the inorganic filler is less than 10 parts by weight, the flame resistance and workability become insufficient, and
If the amount is more than the weight part, the resin viscosity at the time of mixing the inorganic filler becomes high, and it becomes difficult to impregnate the glass nonwoven fabric, which is not preferable.

[0006]

[Function] Hydroxide compounded in the epoxy resin of the surface layer
It is considered that the reason why the aluminum improves the tracking resistance is that aluminum hydroxide is present on the surface of the formed laminated plate, thereby reducing the proportion of the resin on the surface. Furthermore, the reason why aluminum hydroxide is preferable is that aluminum hydroxide is decomposed by the heat of electric discharge to generate water, and water and the organic matter decomposed by the electric discharge react with each other to generate a volatile substance. Is considered to be prevented.

[0007]

Examples of the present invention and comparative examples (conventional examples) are described below.
Is shown. “Parts” indicates “parts by weight” and “%” indicates “% by weight”. Example 1 The composition of the epoxy resin-containing varnish of the surface layer is as follows. (1) 100 parts of non-brominated epoxy resin (Ep-850 manufactured by Yuka Shell) (2) Dicyandiamide 2 (3) 2-phenyl-4-methylimidazole 0.15 (4) Methyl cellosolve 20 (5) Acetone 30 Mixing each material and uniform epoxy resin varnish (I)
Was prepared. Subsequently, the following inorganic filler was added to the epoxy resin varnish (1) with respect to 100 parts of the resin component, followed by stirring and mixing to prepare an inorganic filler-containing varnish. (6) 50 parts of gibbsite type aluminum hydroxide (Heidilite H-42 manufactured by Showa Denko) This varnish containing an inorganic filler is coated with a glass woven fabric (WB- manufactured by Nittobo).
18KRB-84) was impregnated and dried so that the resin content was about 35% to obtain a glass woven prepreg (A).

Next, the composition of the epoxy resin-containing varnish of the intermediate layer is as follows. (1) 100 parts of brominated epoxy resin (Ep-1046 manufactured by Yuka Shell) (2) Dicyandiamide 4 (3) 2-ethyl-4-methylimidazole 0.15 (4) Methyl cellosolve 36 (5) Acetone 60 Each of the above Uniform epoxy resin varnish by mixing materials (II)
Was prepared. Subsequently, the following inorganic filler was added to the epoxy resin varnish (II) with respect to 100 parts of the resin component, and the mixture was stirred and mixed to prepare an inorganic filler-containing varnish. (6) 60 parts of gibbsite type aluminum hydroxide (Heidilite H-42 manufactured by Showa Denko) This varnish containing an inorganic filler was added to a glass nonwoven fabric (EP-4075 manufactured by Nippon Vilene) with a resin and inorganic filler content of 90 parts.
% To obtain a glass nonwoven prepreg (B). Next, three glass non-woven fabric prepregs (B) were stacked to form an intermediate layer, one glass woven prepreg (A) was placed on each of the upper and lower surface layers, and a copper foil having a thickness of 18 μm was further stacked on both surfaces thereof. 170 ° C, pressure 60kg
/ Cm ² for 90 minutes to obtain a copper-clad laminate having a thickness of 1.6 mm.

Example 2 In the prepreg (A) of the epoxy resin glass woven fabric containing an inorganic filler of Example 1, the amount of gibbsite-type aluminum hydroxide was changed from 50 parts to 10 parts.
A copper-clad laminate was obtained in the same manner as in Example 1, except that 0 part was used. << Comparative Example 1 >> Instead of the inorganic filler-containing epoxy resin glass woven prepreg (A) of Example 1, a non-brominated epoxy resin varnish (I) containing no inorganic filler is directly impregnated into the glass woven fabric and dried. As a result, an epoxy resin glass woven prepreg having a resin content of about 45% was obtained. Thereafter, a copper-clad laminate was obtained in the same manner as in Example 1. << Comparative Example 2 >> Instead of the epoxy resin glass woven fabric prepreg (A) used for the surface layer of Example 1, a brominated epoxy resin varnish (II) containing no inorganic filler is directly impregnated into the glass woven fabric and dried. As a result, an epoxy resin glass woven prepreg having a resin content of about 45% was obtained. Thereafter, a copper-clad laminate was obtained in the same manner as in Example 1.

The copper-clad laminates obtained in the above Examples and Comparative Examples were measured for tracking resistance, solder heat resistance, copper foil peeling strength and UL flame resistance. Table 1 shows the results. In addition, dimensional stability, through-hole plating reliability, electrical insulation, and the like were also measured, but no difference was observed between the example and the comparative example.

[0011]

[Table 1] (* 1) Applied voltage value when no short circuit occurred even when 50% or more of 0.1% ammonium chloride aqueous solution was dropped after etching the copper foil. (* 2) In the UL combustion test, the average value of the time until smoke is eliminated.

[0012]

The laminate for printed circuits of the present invention is particularly suitable for industrial printed circuit boards, because it has particularly excellent tracking resistance, UL flame resistance, heat resistance and copper foil peeling strength. is there.

Claims (2)

(57) [Claims] The surface layer is non-brominated as an epoxy resin.
An epoxy resin is used, and aluminum hydroxide is used as an inorganic filler in an amount of 10 parts by weight based on 100 parts by weight of the resin of the surface layer.
A laminated board for a printed circuit, comprising a glass woven fabric impregnated with an epoxy resin containing up to 200 parts by weight. 2. The printed circuit laminate according to claim 1, wherein the intermediate layer is mainly composed of a brominated epoxy resin, and the inorganic filler is 10 to 20 parts by weight based on 100 parts by weight of the resin.
A laminated board for a printed circuit, comprising a glass nonwoven fabric impregnated with epoxy resin containing 0 parts by weight.