JPS6084336A - Prepreg for laminated sheet - Google Patents

Abstract

PURPOSE:To prevent the formation of voids during molding, by making the flowability of resin on both sides in the direction of the width of a base higher than that of resin in the center in forming a prepreg for a laminated sheet by impregnating a base with a resin varnish and drying it. CONSTITUTION:The wall of a drying oven 8 of a radiant dryer 1 is provided with radiant surfaces 2 opposed to each other. A radiation-screening member 5 is formed on the surface of each radiant surface 2 along the traveling direction of a resin varnished-impregnated base 4 in a position corresponding to the center of the width of the base 4. A resin varnished-impregnated base 4 is fed to the drier 4 and dried by conveying it in such a manner that it faces the radiant surface 2 parallelly to produce a prepreg for a laminated sheet in which the flowability of resin during curing on the center in the direction of width is higher than that of resin on both sides. When the prepregs are laminated and molded, the flow of air along the centers is smooth, so that no void is formed in the center.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a pre-register for laminates.

[Background technology]

In addition, prepreg is manufactured by uniformly drying the entire surface of a base material impregnated with resin varnish, and when manufacturing copper-clad laminates using this prepreg, copper foil is first applied to the prepreg. It is manufactured by bonding and heat-pressing molding.

However, the flow of the resin in the prepreg 1G during molding is as follows: @1
There was almost no flow of resin in the central part of the prepreg (6) in the direction of arrow A shown in the figure, so there was a drawback that the central part of the pre-preg register 16) could not be defoamed and remained as a void (7). . This caused a decline in the heat resistance and insulation properties of the manufactured laminate.

[Purpose of the invention]

The invention has been made in view of the above points, and is a product that improves heat resistance and insulation properties by eliminating voids occurring in the central portion. The purpose of this invention is to provide a prepreta for i-boards.

[Disclosure of the invention]

That is, the present invention is a pre-register for a laminate formed by impregnating a base material (4) with a resin varnish (3) and drying the resin varnish (3) in the center of the base material (4) in the width direction. The above object has been achieved by a pre-register for a laminate, which is characterized in that its flowability is greater than that of the resin at both ends.

The present invention will be explained in detail below. As shown in Figure 2, the radiation dryer ill has two drying ovens (81[8) on the left and right, a feed roll (9) and a take-up roll (1o
) by passing one long substrate (4) impregnated with 4-fit fat varnish into one drying oven (8), and then transferring the substrate (4) into the other drying oven (8). , both drying ovens +81 +
The resin varnish [3] in the base material (4) is dried within the chamber 81. A radiant surface (2) is provided on the wall of the drying oven (8) to face the radiant surface (2).
Transport the Jt fat varnish impregnated base material (4) and shoot both widths 11
The resin varnish (3) is dried by radiant heat from i21. As shown in FIG. 3, a radiation shielding part (5) is formed on the surface of the radiation surface +21 at a position corresponding to the widthwise center of the base material 14) along the conveyance direction of the base material (4). It is. As this radiation shielding part (5), a shielding plate such as an aluminum plate may be used to cover the surface of the radiation surface 12), or a material with low emissivity may be coated on the surface of the radiation surface (2). Additionally, the central portion of the radiation surface may be formed of a material with low emissivity.

In this way, the resin varnish-impregnated base material]4) is continuously dried using the radiant surface 12) whose emissivity is lower in the central part than in both ends, and the Zurizu register (6) is continuously dried. The central part in the width direction of the manufactured prepreg 16) is blocked by the radiation shielding part (5) from the radiant heat from the radiant surface 12+, and the curing of the resin does not proceed. Both ends of 6) are sufficiently heated by the radiant heat from the radiant surface (2), and the resin at both ends progresses in hardening. In FIG. 4, (9) is a low-cure area where the resin is not sufficiently cured, and (10) is a high-cure area where the resin is sufficiently cured. Next, Puri-zushi I) [6
) are piled up in the required number, copper foil or the like is placed on the top surface or both the upper and lower surfaces, and the stack is formed to obtain a laminate.

However, since the degree of curing of the resin at the center of the prepreg (6) is lower than that at both ends, the resin at the center flows more easily during molding than at both ends. Because it flows first, the air in the center can be carried smoothly to the outside along with the flow of resin. Therefore, the laminate is degassed uniformly, leaving voids (7). There is no such thing.

Next, the present invention will be specifically explained based on examples. The base material was impregnated to a diameter of 50 mm, and then the resin varnish was dried by passing it through a radiation type dryer. I got a cash register.

Next, 8 sheets of this prepreg were stacked together, and copper foil with a thickness of 35 microns was placed on both the top and bottom of the prepreg stack, and copper foil was laminated at 50 kg/cod, 165°C, and 120 minutes to form a copper foil. A stretched laminate was obtained.

Next, the number of voids in the obtained copper-clad laminate was observed, and the heat resistance of the copper-clad laminate was measured in accordance with JIS regulations. The results are shown in Table-1. The resin flow ratio between the center and both ends of the Zurizu register is expressed as resin flow in the center/resin flow in the pant area 0-X100, and the value of the resin flow ratio is 100.
If the value is less than 100, it means that the flowability of the resin at the center and both ends is the same. It shows that the sex is good.

Table 1 From the results in the table above, it can be seen that if the flowability of the 4'Ml fat in the center of the zureprej is greater than that at both ends, air will be removed during molding and the laminate will have no voids. Therefore, it was confirmed that both the laminates of Examples 1 and 2 had no voids and thus had improved heat resistance.

〔Effect of the invention〕

In the above-mentioned uninvention, the flowability of the resin at the center is made larger than that at both ends, so the resin at the center is melted earlier than at both ends and flows outward. Air in the center can be smoothly removed to the outside as the 1# fat flows, eliminating voids in the laminate and improving heat resistance and insulation properties.

[Brief explanation of drawings]

Figure @1 is an explanatory diagram of the conventional example, Figure @2 is a schematic cross-sectional view of the Kiban Akira Example, Figure 3 is a perspective view of the main parts of the same as above, and Figure 4 is a front view of the prepreg of the same as above. . fil is a radiant dryer, (2) is a radiant surface, (3) is a tree 1
Back varnish, (4) is base material, (5) is radiation shielding part, (6)
This is a Purizu cash register. Agent Patent Attorney Ishi 1) Choshichi

Claims (1)

[Claims] [11] A laminate plate formed by impregnating and drying a resin varnish on a base material, in which the flowability of the resin at the center in the width direction of the base material is compared to the flowability of the resin at both ends. A pre-register for laminated boards, which is characterized by its large size.