JPH06134912A - Production of composite laminated sheet - Google Patents

Abstract

PURPOSE:To eliminate voids or to reduce warpage by varying the curing degrees of the resin in the respective prepregs on the center side and outside of a core material layer consisting of prepregs and superposing a prepreg of a surface layer on the prepregs of the core material layer to heat and press the same. CONSTITUTION:In the production of a composite laminated sheet, the curing degrees in the respective prepregs arranged on the center side and outside of the core material layer consisting of prepregs are varied. A prepreg of a surface layer is superposed on the prepregs of the core material layer on the center side to be heated and pressed. The prepregs of the core material layer may be constituted so that the prepregs advanced in curing are arranged on the outside or inside. The gel time of the prepregs advanced in the curing of the resin due to JISC-2104 is set to 20-100sec and that of other prepregs is set to 150-220sec. The air permeability of the prepregs arranged on the outside is set to 6-10cm<3>/cm<2>/sec.

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 composite laminate.

[0002]

2. Description of the Related Art Laminates are manufactured by continuously impregnating and drying a resin on a fiber base material, cutting and stacking the prepreg into a predetermined size, and if necessary, stacking metal foil on both sides or one side and heating and pressing. To be done. A composite laminated board is a laminated board using two or more kinds of base materials. Generally, a base material having a large apparent density such as glass cloth on the outside, paper on the center side, glass mat, etc. A base material with a small apparent density is used. An inorganic filler is added to the resin with which the base material is impregnated to improve dimensional stability and through-hole reliability and impart flame retardancy.

The resins used include thermosetting resins represented by phenol resins, epoxy resins, unsaturated polyester resins, diallyl phthalate resins, unsaturated acrylic resins, vinyl ester resins and the like. The filler to be blended with the resin is an inorganic substance such as aluminum hydroxide, clay, talc, wollastonite, antimony trioxide, etc., and one kind or a combination of two or more kinds is used. The filler is mixed in an amount of 5 to 200 parts by weight with respect to 100 parts by weight of the resin.

[0004]

By the way, since the composite laminate is composed of base materials having different properties,
Easy to warp after molding. Warpage can be reduced by increasing the resin curing degree of the prepreg, but voids remain and cannot be put to practical use because the resin does not flow sufficiently during molding. Further, if the curing degree of the prepreg resin is lowered, the resin flows out and the plate thickness at the end portion becomes thin, and the warpage characteristics cannot be obtained at good values. An object of the present invention is to provide a manufacturing method capable of obtaining a composite laminate without voids and having good warpage characteristics.

[0005]

According to the present invention, the prepreg of the core material layer is configured such that the prepreg disposed on the center side and the prepreg disposed on the outer side have different degrees of curing of the resin.
A method for producing a composite laminated plate, characterized in that a prepreg of a surface layer is superposed on a prepreg of a core material layer and heated and pressed.

Regarding the degree of cure of the resin of the prepreg of the core material layer, even if the degree of cure of the resin of the prepreg arranged on the center side is advanced, and vice versa, the degree of cure of the resin of the prepreg arranged outside is advanced. Good.

When the degree of curing of the resin of the prepreg arranged on the outer side is advanced, the air permeability of the outer prepreg is set to 6
10 to 10 cm ³ / cm ² / sec. When it exceeds 10 cm ³ / cm ² / sec, the resin in the prepreg on the center side cannot fill the voids in the outer prepreg, and a void remains in the molded product. On the other hand, if it is less than 6 cm ³ / cm ² / sec, the resin of the prepreg on the center side does not reach between the outer prepreg and the outer cloth, and the interlayer adhesive force between the outer cloth and the core material is insufficient, which may cause a punching process. Easy to peel off.

The air permeability is adjusted by changing the density of the base material used for the core material and the gap during resin coating.

Regarding the fiber base material impregnated with the resin, glass, inorganic fibers such as asbestos, polyester,
Synthetic fibers such as polyamide and cellulose mixed paper are used as the nonwoven fabric. On the outside, woven fabric of inorganic fibers or synthetic fibers, or cellulosic paper or a mixed paper of cellulosic paper and inorganic fibers can be used.

The degree of cure of the prepreg resin is represented by gel time as an index. In the present invention, the gel time according to JISC2104 of the prepreg in which the resin has hardened is 20.
~ 100 seconds, other prepreg JISC2104
The gel time according to the above method is 150 to 220 seconds.

If the gel time of the prepreg in which the degree of curing of the resin has advanced is 100 seconds or more, there is no warp prevention effect, and
If the time is 20 seconds or less, the resin will be excessively hardened, and it will be difficult to perform lamination molding. If the gel time of the other prepreg is 220 seconds or more, the resin flow during molding is too large, and if it is 150 seconds or less, the fluidity is so small that voids cannot be filled.

The gel time can be adjusted by any of the following methods, but any method may be used. 1 Change the amount of the curing agent or curing accelerator added to the varnish. 2 Change the coating speed. 3 Change the coating temperature.

[0013]

In the prepreg having a high degree of curing of the resin, the flow of the resin is small, and thus the residual stress strain due to the flow of the resin is small. And the voids that remain because the fluidity of the resin is small,
Fill with resin of other prepreg with high resin flowability.
For this reason, the stress is small even if the flow of the resin in the inner layer is large, the residual stress as a whole is small, and the strain is small, so that warpage does not occur.

[0014]

【Example】

Example 1 100 parts by weight of brominated epoxy resin for laminated plate, 4 parts by weight of dicyandiamide and 0.15 part by weight of 2-methyl-4-ethylimidazole, 30 parts by weight of N, N-dimethylformamide and 30 parts by weight of 2-methoxyethanol. Dissolved in a solvent consisting of parts. Furthermore, aluminum hydroxide (CL-manufactured by Sumitomo Chemical Co., Ltd.) is used with respect to 100 parts by weight of the resin content.
310) was added and stirred to form a varnish.

Glass non-woven fabric (E manufactured by Japan Vilene Co., Ltd.
PM-4060N) was coated with the varnish so that the resin content was 90.0 ± 2.0% and dried. At this time, the gel time of the B stage resin was changed to 70 by changing the drying temperature.
Second glass non-woven fabric prepreg (A) and 180 second glass non-woven fabric prepreg (B) were obtained.

A glass cloth (WE-18K-RB84 manufactured by Nitto Boseki Co., Ltd.) was coated with a varnish having the same composition as the above varnish except that it did not contain aluminum hydroxide, and the resin content was 41.0 ± 3.0%.
And was dried to obtain a glass woven prepreg.

The glass nonwoven fabric prepreg (A) is laminated on the upper and lower sides of the glass nonwoven fabric prepreg (B), and the glass woven fabric prepreg is further laminated on the upper and lower sides thereof, and the outermost layer is an electrolytic copper foil having a thickness of 18 μm (manufactured by Nippon Denshoku Co., Ltd.). ) Is placed at a temperature of 170
The temperature is 1.70 ° C. and the pressure is 2.94 MPa for 70 minutes, and the thickness is 1.
A 6 mm copper clad laminate was obtained. No void was observed in the obtained laminate.

Example 2 The procedure of Example 1 was repeated except that the arrangement of the prepreg of the core material layer was reversed from that of Example 1, that is, the glass nonwoven fabric prepreg (A) was overlaid with the glass nonwoven fabric prepreg (B). A 1.6 mm thick copper clad laminate was obtained. No void was observed in the obtained laminate.

Comparative Example 1 The same glass non-woven fabric was used in the same manner as in Example 1 except that the resin content was 90.0 ±.
A glass nonwoven fabric prepreg (C) in which the gel time of the B-staged resin was 130 seconds was obtained by applying the coating solution to 2.0% and drying. Three pieces of this glass nonwoven fabric prepreg (C) were laminated, the same glass woven fabric prepreg was laminated on the upper and lower sides thereof, electrolytic copper foil having a thickness of 18 μm was arranged as the outermost layer, and a thickness of 1 was obtained under the same conditions as in the embodiment. A copper-clad laminate of 0.6 mm was obtained. Table 1 shows the warpage characteristics of the copper-clad laminate obtained as described above.

[0020]

[Table 1]

Example 3 Glass woven fabric prepregs (D), (E) and (F) were made with the same varnish as in Example 1, except that the amount of solvent was changed. The glass nonwoven fabric prepreg (D) has a gel time of 70 seconds and an air permeability of 3 cm ³ / cm ² / second, and the glass nonwoven fabric prepreg (E) has a gel time of 70 seconds and an air permeability of 1
1cm ³ / cm ² / sec, nonwoven glass fabric prepreg (F) is air permeability in gel time 180 seconds 4cm ³ / cm ² / sec. The air permeability of the glass nonwoven fabric prepreg (A) is
It is 8 cm ³ / cm ² / sec.

The glass nonwoven fabric prepreg (A) is laminated on the upper and lower sides of the glass nonwoven fabric prepreg (D), and the glass woven fabric prepreg is laminated on the upper and lower sides thereof, and the outermost layer is an electrolytic copper foil having a thickness of 18 μm (manufactured by Nippon Denshoku Co., Ltd.). ) Is placed at a temperature of 170
The temperature is 1.70 ° C. and the pressure is 2.94 MPa for 70 minutes, and the thickness is 1.
A 6 mm copper clad laminate was obtained. No void was observed in the obtained laminate.

Comparative Example 2 Glass nonwoven fabric prepregs (A) were laminated on the upper and lower sides of the glass nonwoven fabric prepregs (E), glass woven fabric prepregs were further laminated on the upper and lower sides thereof, and an electrolytic copper foil having a thickness of 18 μm was used as the outermost layer (Japan Electrochemical ( (Manufactured by K.K. Co., Ltd.), and heated and pressed at a temperature of 170 ° C. and a pressure of 2.94 MPa for 70 minutes to obtain a copper-clad laminate having a thickness of 1.6 mm.

Comparative Example 3 Nonwoven glass prepreg (A) was laminated on the upper and lower sides of the nonwoven glass prepreg (F), glass woven prepreg was further laminated on the upper and lower sides thereof, and electrolytic copper foil having a thickness of 18 μm was used as the outermost layer (Japan Electrolytic ( (Manufactured by K.K. Co., Ltd.), and heated and pressed at a temperature of 170 ° C. and a pressure of 2.94 MPa for 70 minutes to obtain a copper-clad laminate having a thickness of 1.6 mm.

The copper foil of the copper clad laminates obtained in Example 3, Comparative Example 2 and Comparative Example 3 was removed by etching, and the appearance and interlayer adhesion were measured. The results are shown in Table 2.

[0026]

[Table 2]

[0027]

According to the present invention, the core material layer is formed by combining the prepregs having different degrees of curing of the resin, so that the stress strain generated in the laminated board is reduced and the core material layer outside the core material layer is formed. It is possible to manufacture composite laminates that have no voids and small warpage.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Kenichi Ohori 1500 Ogawa, Shimodate-shi, Ibaraki Hitachi Chemical Co., Ltd. Shimodate factory (72) Inventor Akinori Hanawa 1500 Ogawa, Shimodate-shi, Ibaraki Hitachi Chemical Co., Ltd. Shimodate factory

Claims (5)

[Claims] 1. The core material prepreg is configured such that the prepreg arranged on the center side and the prepreg arranged on the outside have different curing degrees of resin, and the prepreg of the surface layer is superposed on the prepreg of the core material layer and heated. A method for manufacturing a composite laminate, which comprises applying pressure. 2. The prepreg of the core material layer is configured such that the prepreg in which the resin is hardened is arranged outside the prepreg arranged on the center side, and the prepreg of the surface layer is superposed on the prepreg of the core material layer. The method for producing a composite laminated plate according to claim 1, wherein heating and pressing are performed. 3. The prepreg of the core material layer is configured such that the prepreg in which the resin has been hardened is arranged inside the prepreg arranged on the center side, and the prepreg of the surface layer is superposed on the prepreg of the core material layer. The method for producing a composite laminated plate according to claim 1, wherein heating and pressing are performed. 4. A prepreg JIS according to which curing of a resin is advanced.
The gel time by C2104 is 20 to 100 seconds,
The method for producing a composite laminate according to claim 2 or 3, wherein the gel time of another prepreg according to JIS C2104 is 150 to 220 seconds. 5. The air permeability of the outer prepreg is 6
The method for producing a composite laminate according to claim 2, wherein the production rate is 10 cm ³ / cm ² / sec.