JPS5970571A - Drier for resin impregnated sheet for laminated board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drying apparatus for resin-impregnated sheets for laminated boards used in printed wiring boards and the like.

The laminate is made by impregnating a base material such as paper or glass cloth with a thermosetting resin varnish such as phenolic resin varnish or Epo+ resin varnish to create a resin-impregnated sheet. After drying the prepreg (3) with a drying device, it is cut into a fixed size, and multiple sheets of this prepreg (3) are stacked and heated on a heating plate (4++41 as shown in Figure 1). It is obtained by pressure molding.Here, when the prepreg (3) is heated and pressurized between the hot plates f41+4+, the ends of the prepreg (3) undergo heat radiation, etc., and the heating temperature becomes lower and the prepreg ( The central part of 3) accumulates heat and the heating temperature becomes high, so this old prepreg (3)
The melt viscosity of the impregnated resin is high in the center of the FF because it is heated to a high temperature, but the melt viscosity of the impregnated resin is low at the end of the FF 1 nozzle (3) because the heating temperature is not high. ! The molten resin at the edge of the prepreg (3) flows out due to the pressure applied by the ll plate (4) (41), which tends to cause variations in plate thickness such as thinning of the edge of the laminate and variations in product performance. However, resin-impregnated sheet +
Conventionally, the apparatus for drying K!
Divide P (2+) into multiple dry leans (2a) (2b)...K in the feeding direction of the resin-impregnated sheet (1), and, for example, dry the central drying lean (2b) at 150°C on the input 1'' side. The drying lean (2b) on the center side is heated to a high temperature, and the drying lean (2b) on the end side is set to a high temperature, and the drying lean (2a) on the end side is set to 110°C, and the drying sonia (2c) on the outlet side is set to 120°C.
2c) is set at a low temperature, but this drying device cannot dry the resin-impregnated sheet in the middle direction, and is not suitable for hot-press molding as described above. No attempt has been made to solve this problem during drying of the resin-impregnated sheet (1).

Kinoe IJII has been developed in view of the above points, and aims to provide a drying device for resin-impregnated sheets for laminates that can obtain prepregs with suppressed variations in melt viscosity during hot-press molding. This is the purpose.

Therefore, in the present invention, the inside of the oven (2) has a plurality of drying genes (2a
) (2b)... The center drying line (2b) is heated to a low temperature and the end side drying line (2a) (
The above object has been achieved by means of a drying apparatus for a resin-impregnated sheet for a laminate, which is characterized in that 2c) is set at a high temperature.The present invention will be described in detail below with reference to Examples.

As shown in FIGS. 3(a) and 3(b), the drying device according to the present invention has a furnace (2) with a plurality of drying genes (2a), (2b),・
It is divided into ・Each ¥L butterfly lean (2a) (2b)
! The heating machine (5) is divided corresponding to '. As this heating device (6), any type of heating device such as an infrared heating type or a hot air blowing type can be used. Therefore, in the embodiment shown in FIGS. 3(a) and 3(b), the drying material (2a), (2b), and (2c) is divided into three parts in the middle direction, the center and both sides. dry lean (2b
Adjust the output of each heating machine (5) (5)... so that the drying machine (2a) (2C) on both sides is at a low temperature and the drying machine (2a) (2C) is at a high temperature. ) to 12
．． Dry on both sides at 0℃, no, 7 (za) (2c)
Set the drying temperature to 1ffO<0>C. Of course, the dry lean may be divided into a larger number of parts than in the above embodiment. When the resin-impregnated sheet +1) impregnated with the thermosetting resin varnish is sent into the oven (2) of the drying device, the resin-impregnated sheet f1+ is heated weakly in the central part in the <,l'l] direction. Because the heating is strong at both ends,
In the resin-impregnated resin (3) obtained by drying the resin-impregnated sheet 1-+1.1, the hardening of the impregnated resin at the end portions of In-C progresses more than the co-impregnated resin at the central portion. Therefore, using this prepreg (3), heat plate (4) as shown in Figure 1 is used.
Prepreg (
Even if the heating in step 3) is carried out at a higher temperature in the center and lower at the edges, the JR resin at the edges is more cured than the resin at the center, so the prepreg (3) is The melt viscosity of the resin has a similar value between the center and the ends, and it is possible to prevent the melt viscosity from varying between the center and the ends (incidentally, the variation in melt viscosity can be suppressed to 5°cps or less. Conventionally, there is usually a variation of 200 to 300 cps), but it is possible to prevent the resin from flowing out from the end of the pre-register (3) during hot press molding, and the molding pressure is applied to the entire surface of the pre-register (3). It can be applied uniformly over the entire area, reducing the rate of defects (by the way, conventionally, defects occurred at about 5 to 10%, but 3.
The following cases can be reduced).

As mentioned above, in the drying apparatus of the present invention, the inside of the furnace is divided into a plurality of drying genes in the middle direction with respect to the feeding direction of the resin-impregnated sheet, and the drying gene on the central side is at a low temperature and the drying lean on the end side is Since the temperature is set at a high temperature, the resin-impregnated sheet can be dried in a state where the resin has hardened more at the edges than at the center. It is possible to obtain a replenisher with reduced variation in melt viscosity.

[Brief explanation of the drawing]

Figure 4M1 is a front view showing the process of thermoforming, Figure 2 1d is a schematic plan view of a conventional example, Figure 3 (a) is a schematic plan view of an embodiment of Kekiseri J, and Figure 3 (b) is a schematic plan view of a conventional example. ) is X- in Figure 3(a)
It is an X-ray cross-sectional view, (1) is a resin-impregnated sheet 1-1 (2)
(2a), (2b), (2c) are drying/nonte. Agent Patent Attorney Ishi 1) Chief 71 Figure (0) (b)

Claims (1)

[Claims] (1) The inside of the furnace is divided into multiple drying leans in the middle direction with respect to the feeding direction of the resin-impregnated sheet.
1. A drying device for resin-impregnated sheets for laminated boards, characterized in that the drying lean on the edge side is set at a high temperature while the drying lean on the edge side is set at a low temperature.