JP2001121534A - Preparation of laminated sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for preparing a laminated sheet wherein even when the thickness of the sheet is thin, blackness and uniformity of color can be obtained. SOLUTION: The first coloring process wherein a thermosetting resin varnish is colored with a black coloring agent, the second coloring process wherein a glass base material is colored with the black coloring agent, an impregnating process wherein the glass base material obtained in the second coloring process is impregnated with the thermosetting resin varnish obtained in the first coloring process and then, dried to obtain a prepreg and a press process wherein the prepreg obtained in the impregnating process is pressed while it is heated are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a laminate used for a circuit board.

[0002]

2. Description of the Related Art In general, a laminated board used for an electric circuit board (printed wiring board) is prepared by impregnating a glass substrate (glass cloth) with a thermosetting resin varnish and drying the prepreg. Manufactured by pressing.

As a method of making such a laminate black, there is a method of impregnating and drying a glass substrate with a thermosetting resin varnish containing a pigment such as carbon or an azo black dye (first method). the method of).

There is also a method of obtaining a black color by impregnating and drying a thermosetting resin varnish containing no black pigment or dye on a glass substrate colored with a black pigment (second method).

[0005]

However, with the recent reduction in the thickness of electronic components, blackness is required even for a thin laminate having a thickness of 0.1 mm or less. When the laminate is made black by the first method described above, light transmission may occur in the glass substrate. On the other hand, if the second method is used to make black, light transmission may occur in the resin layer, and in any of the first and second methods, blackening (blackness) is not sufficient. There is a problem that unevenness occurs in hue.

Accordingly, an object of the present invention is to provide a method of manufacturing a laminated board which can achieve sufficient blackness and color uniformity even with a small thickness.

[0007]

According to the present invention, there is provided a method of manufacturing a laminate, comprising: a first coloring step of coloring a thermosetting resin varnish with a black coloring agent; and coloring a glass substrate with a black coloring agent. A second coloring step, a thermosetting resin varnish obtained in the first coloring step is impregnated into the glass base material obtained in the second coloring step, and then dried to obtain a prepreg. Pressurizing while heating the prepreg.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, when a black laminated board is manufactured, first, in a first coloring step, a black coloring agent is blended with the thermosetting resin varnish to form a thermosetting resin varnish. Is colored. The thermosetting resin used for the thermosetting resin varnish is not particularly limited, but an epoxy resin, a polyimide resin, a phenol resin, a polyester resin, or the like can be used.

In the second coloring step, the glass substrate is colored black by coloring the glass substrate with a black colorant. As a glass substrate, MIL specification standard 108
Glass cloth (glass cloth) of 0, 2116, 7628 type or the like can be used, and the thickness, woven density, and the like are not particularly limited.

[0010] In the present specification, a coloring agent refers to a pigment or a dye.
There is no particular limitation as long as carbon, oil-soluble azo dyes and the like can be used and black can be obtained.

[0011] In the impregnation step, the thermosetting resin varnish obtained in the first coloring step is impregnated into the glass cloth obtained in the second coloring step, and the glass cloth impregnated with the thermosetting resin varnish is dried to prepare a prepreg. Get.

In the pressing step, the prepreg obtained in the impregnation step is heated and pressed to obtain a laminate.

[0013]

Example 1 90 parts by weight of a brominated bisphenol A type epoxy resin (epoxy equivalent: 480) and 1 part of an orthocresol novolak type epoxy resin (softening point: 80 ° C.)
0 parts by weight, 2 parts by weight of dicyandiamide, 2-ethyl-
0.2 parts by weight of 4-methylimidazole, 30 parts by weight of ethylene glycol monomethyl ether, and 0.5 part by weight of a black chromium complex azo dye were blended to prepare a colored thermosetting resin varnish (first coloring step). .

On the other hand, a glass cloth (glass substrate) of MIL specification standard 2116 type was colored with an azo black pigment (second coloring step).

Next, the colored thermosetting resin varnish (hereinafter simply referred to as “colored resin varnish”) produced in the first coloring step is replaced with a glass cloth colored in the second coloring step (hereinafter simply referred to as “colored glass cloth”). ), And the colored glass cloth impregnated with the colored resin varnish was dried to obtain a prepreg (impregnation step).

Then, an electrolytic copper foil having a thickness of 35 μm is arranged on both sides of the prepreg obtained in the impregnation step, and press-formed at a pressure of 4 MPa while heating at 170 ° C. for 90 minutes (press step). As a result, a double-sided copper-clad laminate having a thickness of 0.1 mm was produced.

COMPARATIVE EXAMPLE 1 A colored resin varnish obtained in the first coloring step similar to that of Example 1 was subjected to uncolored MIL specification standard 211.
Six types of glass cloth were impregnated so that the resin content was 48% by weight, and an uncolored glass cloth impregnated with a colored resin varnish was dried to obtain a prepreg. This prepreg was subjected to the same pressing process as in Example 1 to a thickness of 0.1%.
mm double-sided copper-clad laminates were produced.

Comparative Example 2 An uncolored thermosetting resin varnish obtained by removing the black chromium complex azo dye from the colored resin varnish of Example 1 was applied to the colored glass cloth obtained in the second coloring step as in Example 1. And a colored glass cloth impregnated with a non-colored thermosetting resin varnish was dried to obtain a prepreg. This prepreg was subjected to the same pressing process as in Example 1 to a thickness of 0.1 m.
m of the double-sided copper-clad laminate was manufactured.

Table 1 shows the measurement results of the brightness and color unevenness of the double-sided copper-clad laminates manufactured according to the above-described Examples and Comparative Examples.
Shown in The lightness of the double-sided copper-clad laminate was measured using a colorimetric colorimeter (Suga Test Instruments Co., Ltd., SM Color Comput).
er model SM4) was used to measure a sample obtained by etching each double-sided copper-clad laminate to 50 mm × 50 mm. Further, uneven color (uneven hue) was visually determined.

[0020]

[Table 1]

As is clear from Table 1, Example 1 was superior to Comparative Examples 1 and 2 in terms of blackness and color unevenness. Therefore,
Even with a thin laminate of 0.1 mm, sufficient blackness and color uniformity can be achieved.

In Example 1, one prepreg was heated and pressed to obtain a black laminated plate. However, a predetermined number of the same prepregs as in Example 1 were stacked and heated and pressed to obtain a black laminated plate. May be obtained, and even in this case, the first embodiment
It has the same effect as. Also, the thickness of the laminate is 0.1 m
Even if m or less, the same effect as in the first embodiment is obtained. Furthermore, in Example 1, glass cloth was used as the glass substrate, but the present invention is not limited to this, and the same effects as in Example 1 can be obtained even with glass-mixed paper, glass nonwoven fabric, or the like.

[0023]

According to the method for producing a laminate of the present invention, sufficient blackness and color uniformity can be achieved even with a thin laminate.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29L 9:00 B29L 9:00 31:34 31:34 C08L 101: 00 C08L 101: 00 (72) Inventor Kosuke Takada 1500 Ogawa, Odate, Shimodate City, Ibaraki Prefecture F-term in Shimodate Works of Hitachi Chemical Co., Ltd. FB11 FB22

Claims (1)

[Claims] 1. A first coloring step of coloring a thermosetting resin varnish with a black coloring agent, a second coloring step of coloring a glass substrate with a black coloring agent, and a first coloring step. A thermosetting resin varnish is impregnated into the glass substrate obtained in the second coloring step and then dried to obtain a prepreg, and a press step of heating and pressing the prepreg obtained in the impregnation step is provided. A method for producing a laminate, characterized in that: