JPH05318482A - Manufacture of laminate - Google Patents

Abstract

PURPOSE:To manufacture a laminate of superior surface smoothness optimum for the manufacture of a printed wiring board for a fine pattern by impregnation drying thermosetting resin varnish such as epoxy resin on a specified glass cloth to manufacture a prepreg and laminate molding the given number of prepregs. CONSTITUTION:A glass cloth having square or rectangular spaces 3 formed by warps 1 and wefts 2 and the ratio a/b of (the length (a) of the side of warps 1 of the spaces 3) (the length (b) of the side of wefts 2) of 0.9 to 1.1 is used for forming the glass cloth weaved by glass yarn warps 1 and wefts 2. A prepreg is manufactured by impregnating and drying the glass cloth with, for example, epoxy resin of 100 pts.wt., curing agent dicyandiamide 4.7 parts and epoxy resin varnish composed of a cure accelerating agent 2-ethyl-4-ethyl imidazole and a solvent, 8 pieces of which, for example, are laminated and copper-foils are laminated on both faces, and heat pressure molded to manufacture a copper-plated laminate.

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 laminate having a surface smoothness superior to that of a conventional one.

[0002]

2. Description of the Related Art Thermosetting resin copper clad laminates obtained by laminating an appropriate number of prepregs obtained by impregnating and drying thermosetting resins such as epoxy resins and molding under heat are mainly used for industrial electronic equipment. It is used as a material for printed wiring boards for office automation equipment and the like, and the properties required for this laminated board are more and more diverse. In recent years, along with miniaturization and refinement in the electric and electronic fields, the demand for higher density of printed wiring boards has been increasing, and the demand for surface smoothness as a laminated board has become stronger and stronger. For example, in the case of creating a fine pattern in which five or more signal lines are passed with a standard through hole pitch of 2.54 mm, a saw blade-like defect may occur in the pattern if the unevenness of the surface of the copper clad laminate is large. Was causing the worse.

Conventionally, as a base material for a laminated plate having excellent surface smoothness, a thin glass cloth (1
(About 00 μm) was used. In addition to the base material,
Means such as reducing the flow during pressing, increasing the amount of resin in the prepreg, and using a varnish containing a filler have been studied. However, it is difficult to reduce the flow and increase the amount of resin in the prepreg due to the problems of plate thickness standard management and formability, and it is economical to use a varnish containing a thin cloth or filler with a large number of implants. Since it is expensive, it is difficult to put it into practical use.

[0004]

SUMMARY OF THE INVENTION The present invention is to improve the surface smoothness of a laminated plate, and the purpose thereof is to use a special material such as thin glass cloth or varnish containing a filler. And to provide a copper-clad laminate having excellent surface smoothness.

[0005]

DISCLOSURE OF THE INVENTION The present invention is a glass cloth obtained by weaving glass yarns as warp yarns and weft yarns and is formed by warp yarns (1) and (2) as shown in FIG. The shape of the void (3) is square or rectangular, and the ratio of the length (a) on the warp side of the void / the length (b) on the warp side (a /
b) using a glass cloth having a value of 0.9 or more and 1.1 or less,
It is a method for producing a laminated plate, which comprises impregnating and drying a thermosetting resin varnish such as an epoxy resin to obtain a prepreg, and laminating and molding a predetermined number of the prepreg. Air permeability is 3 ml / cm ² / sec
The following is a method for producing a laminated plate using a glass cloth.

The present invention will be described in detail below. In the glass cloth according to the present invention, the formation of the warp and the void formed by the warp is square or rectangular, and as shown in FIG. 1, the ratio of the length (a) on the warp side of the void to the length (b) on the warp side ( It is woven so that a / b) is 0.9 or more and 1.1 or less. Preferably the voids are square, ie the a / b ratio is 1.0
Is preferred. The thickness of the warp, the monofilament of the warp, and the number of bundles are not particularly limited. Depending on the case, warp yarns and warp yarns having different thicknesses and different numbers of bundles may be used. However, it is preferable that the same yarn is used for the warp and the weft. The thickness of glass cloth is usually 0.05-
It is 0.3 mm, but is not particularly limited. Also, the twisting direction is not limited.

The glass cloth subjected to the fiber-opening treatment is more effective. The air permeability of the glass cloth is generally about 10 ml / cm ² / sec, whereas the air permeability of the glass cloth according to the present invention is 3 ml / cm ² / sec.
It is below, preferably below 1 ml / cm ² / sec. This is very effective because the opening of the glass cloth is close to a square so that the warp and the weft can be uniformly subjected to the opening process. As a method for opening the glass cloth, a method is generally used in which air, a gas such as an inert gas, or a liquid such as water or an organic solvent is previously sprayed to physically open the cloth. The degree of opening can be arbitrarily controlled by the type and flow rate of the sprayed fluid. The air permeability was measured using the Frazier type tester described in JIS L 1096 6.27.1. The thermosetting resin used in the present invention includes polyimide resin, phenol resin, polyester resin and the like in addition to epoxy resin, and is not particularly limited.

Example 1 As shown in FIG. 1, the void a / b ratio (length on the warp side / length on the weft side) was 1.0, the weight was 215 g / m ² , and the thickness was 0.1.
Using 184 mm of glass cloth A, 100 parts by weight of epoxy resin (Ep-5045 made by Yuka Shell Epoxy) (hereinafter referred to as "part"), hardener dicyandiamide 4.7
Part, a curing accelerator 2-ethyl-4-methylimidazole and an epoxy resin varnish consisting of a solvent were impregnated and dried to obtain a prepreg. Eight sheets of this prepreg are laminated, copper foil (thickness 18 μm) is laminated on both sides, and heat and pressure molding is applied to obtain a plate thickness of 1.6.
A copper clad laminate having a size of mm was obtained. Example 2 The glass cloth used in Example 1 was subjected to a fiber-spreading treatment to obtain a glass cloth B having an air permeability of 1.5 ml / cm ² / sec. Got Comparative Example 2 As shown in FIG. 1, the void a / b (length on the side of warp / length on the side of weft) is 1.25, the weight is 215 g / m ² , and the thickness is 0.1.
A glass cloth C of 88 mm is used, and
A copper clad laminate was obtained in the same manner as. The surface roughness of the obtained copper clad laminate was measured. The results are shown in Table 1.

[0009]

[Table 1]

[0010]

The laminate according to the present invention has excellent surface smoothness as compared with the conventional laminate. Therefore, when a circuit is formed, the dry film and the laminated board have good adhesion, which is most suitable for the production of a printed wiring board for fine patterns.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing the structure of a glass cloth.

[Explanation of symbols]

 1 Warp 2 Weft 3 Void

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H05K 1/03 K 7011-4E // B29K 101: 10 105: 08

Claims (2)

[Claims] 1. A glass cloth obtained by weaving glass yarns as warps and wefts, wherein the voids formed by the warps and wefts are square or rectangular, and the length of the voids is the length on the warp side / the length on the weft side. A glass cloth having a thickness ratio of 0.9 or more and 1.1 or less is impregnated and dried with a thermosetting resin varnish such as an epoxy resin to obtain a prepreg, and a predetermined number of the prepregs are laminated and formed. A method for manufacturing a laminated board. 2. The method for producing a laminated sheet according to claim 1, wherein the glass cloth is subjected to an opening treatment, and the air permeability of the glass cloth is 3 ml / cm ² / sec or less.