JPS6225506B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing laminates used in electronic devices and industrial equipment, and its purpose is to uniformly impregnate the substrate with resin, improve the warping of the laminate, and improve electrical insulation. The goal is to improve sexuality. Conventionally, glass nonwoven fabrics, glass-paper mixed nonwoven fabrics, and the like have been known as base materials used for laminates.
The nonwoven fabric is generally supplied as a roll, and there are differences in the extent to which physical force is applied due to the winding, as well as in the amount of moisture absorbed, between the ends and the center in the width direction, or in the machine direction. There are drawbacks such as uneven impregnation in the width direction and flow direction during impregnation, and furthermore, the ends of the prepreg in the width direction curl after impregnation and drying, and laminates using this prepreg have large warps at the ends and poor electrical insulation properties. There were problems such as variations. In order to improve this drawback, methods for reducing unevenness of impregnation by using a large amount of resin diluting solvent during impregnation to reduce impregnation unevenness, or adjusting the tension of the edges of the substrate during impregnation drying, or mechanically tightening the edges Methods to suppress curling are being considered. However, in the former case, a large amount of solvent is required and there are problems with economic efficiency, as well as deformation due to partial physical force (specifically, the central part of the winding is compressed) and moisture absorption differences (specifically, (Moisture absorption is greater at the outside and ends of the windings), which results in warpage of the laminate and does not lead to improvement in insulation. Furthermore, in the latter case, it is extremely difficult to partially adjust the tension, and there is a problem that the base material breaks during continuous impregnation, making this method impossible for mass production. The present invention aims to improve these drawbacks,
The glass nonwoven fabric or the glass-paper mixed paper nonwoven fabric base material is pre-wetted to make the moisture content of the base material uniform, and after adjusting the moisture content in the base material to 3 to 10% by weight, heat curing is performed. The material is laminated and molded using prepreg obtained by impregnating and drying a synthetic resin. The details of the present invention will be explained using an example. In FIG. 1, the glass nonwoven fabric or glass-paper mixed nonwoven fabric base material 2 is pulled out from the roll 1,
The water is passed through a steam or spray water generating furnace 3. At this time, it is preferable to heat the base material, and the treatment time is selected so that the physical deformation of the base material can be alleviated and the water content is uniform, so that the amount of water in the base material 2 is 3 to 3.
It is necessary to adjust it to 10% by weight. If it is less than 3% by weight, deformation cannot be sufficiently alleviated and it is difficult to adjust a uniform moisture content. Moreover, if it exceeds 10% by weight, the subsequent impregnation with the thermosetting resin cannot be achieved at an economical impregnation speed, resulting in a decrease in electrical properties. That is, in the present invention, the glass nonwoven fabrics and glass-paper mixed nonwoven fabric base materials available in the general market are all rolls from the viewpoint of transportation and impregnation mass production, and the problem raised because of the rolls. The purpose is to alleviate and uniformize the curling curl (distortion) and moisture absorption unevenness by wet treatment, eliminate the warping of prepreg edges and impregnation unevenness, and improve the warpage and electrical properties of the final laminate. Commercially available nonwoven glass fabrics or glass-paper mixed nonwoven fabrics can be used in carrying out the present invention. Further, the thermosetting resin can be selectively used by one-stage impregnation or two-stage impregnation, and water-soluble phenolic resins, modified phenolic resins, epoxy resins, etc. can be used. Example As shown in Figure 1, glass with a basis weight of 130 g/m ² -
The paper mixed base material 2 is pulled out from the roll 1 (2500 m), kept at a base material temperature of 50°C for 3 minutes in a steam generating furnace 3, and after adjusting the water content to 7 ± 0.5% by weight, it is transferred to the first impregnation tank. It was impregnated with a methylolated phenol resin solution in step 4 and dried in a drying oven 7. Furthermore, the second
A prepreg 6 that is impregnated with an epoxy resin in an impregnating tank 5 and then dried in a drying oven 8 to maintain the properties shown in Table 1.
was manufactured. After cutting the prepreg, a 35 μ thick copper foil was placed on one side of the prepreg in an 8-ply layer, and the prepreg was inserted into a press. After molding for 60 minutes at a pressure of 80 kg/cm ² and a temperature of 160° C., the molded product was cooled to obtain a single-sided copper-clad laminate having a thickness of 1.6 m/m. The properties of the laminate are shown in Table 2. Comparative example: Pull out the base material 2 from the same scroll 1 as in the example,
As shown in FIG. 2, the base material was directly led to the first impregnating tank 4 and the second impregnating tank 5 without being wetted, and was subjected to the same impregnating treatment with the same resin as in the example, and the results are shown in Table 1. A prepreg 6' was produced which retained its properties. After cutting the prepreg, a single-sided copper-clad laminate with a thickness of 1.6 m/m was obtained using the same configuration and pressing conditions as in the example. The properties of the laminate are shown in Table 2.

[Table] The measured values in Table 1 are shown as the maximum and minimum values of the measured values of 20 samples, respectively. The moisture contained in the base material is a measured value after the wet treatment in Examples, and a measured value after being pulled out from the roll in Comparative Examples. Moreover, the curl of the prepreg edge portion was determined by measuring the amount of lift of the end portion in the width direction of the base material.

[Table] The measured values in Table 2 are shown as the maximum and minimum values of the measured values of 20 samples, respectively. The amount of warpage A is
330 cut from the corner of a 1000 x 1000 mm laminate
The amount of bulge in the center of a 330mm x 330mm sample piece was measured, and the amount of warp B was measured as the amount of bulge in the center of a 330 x 330mm sample piece cut from the center of the same laminate. be. In the above example, the laminate was constructed using only the base material subjected to the wet treatment, but the effect was also obtained with a laminate using this as a part and combining it with other base materials. As shown in Table 1, the prepreg obtained by the method of the present invention has no curl phenomenon at the edges and less variation in the amount of resin, and as shown in Table 2, the absolute value of warp and the edge part of the laminate Its industrial value is extremely great in that it can produce a laminate with excellent quality stability, with little variation in warpage in the center and small variation in electrical properties.

[Brief explanation of the drawing]

FIG. 1 is a simplified sectional view showing the prepreg manufacturing process of the laminate manufacturing method of the present invention, and FIG. 2 is a simplified sectional view showing the prepreg manufacturing process of the conventional laminate manufacturing method. 1 is a scroll, 2 is a base material, 3 is a steam or spray water generating furnace, 4 is a first impregnating tank, 5 is a second impregnating tank, 6 is a prepreg, and 7 and 8 are drying furnaces.

Claims (1)

[Claims] 1. A glass nonwoven fabric or a glass-paper mixed nonwoven fabric base material is pre-wetted to reduce the moisture content in the base material to 3 to 30%.
1. A method for manufacturing a laminate, characterized in that part or all of the prepreg obtained by impregnating and drying a thermosetting resin to 10% by weight is laminated and molded.