JPH07308991A - Unidirectional fiber-reinforced thermoplastic resin prepreg and manufacture of fiber-reinforced thermoplastic resin laminate - Google Patents

Abstract

PURPOSE:To obtain a unidirectional fiber-reinforced thermoplastic resin prepreg having excellent impregnation of matrix resin and excellent orientation of reinforcing fiber and fiber-reinforced thermoplastic resin laminate. CONSTITUTION:A method for manufacturing a unidirectional fiber-reinforced thermoplastic resin prepreg comprises the steps of winding reinforcing fiber 1 and a thermoplastic resin film 3 on a metal plate 3, hot pressing the plate, and melting to integrate the fiber with the film. A method for manufacturing a fiber-reinforced thermoplastic resin laminate comprises the steps of winding a plurality of layers of the fiber 1 and the film 3 on the plate 3 in the same direction or different directions, hot pressing the plate, and melting to integrate the fiber with the film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a fiber-reinforced thermoplastic resin prepreg, and more particularly to a unidirectional fiber-reinforced thermoplastic resin prepreg and a fiber-reinforced thermoplastic resin laminate having excellent orientation of reinforcing fibers. It relates to a manufacturing method.

[0002]

2. Description of the Related Art Conventionally, there is known a manufacturing method for obtaining a unidirectional fiber-reinforced thermoplastic resin prepreg by aligning reinforcing fibers, sandwiching them with a thermoplastic resin film and passing them through a hot roll. However, since the prepreg obtained by this method is set on a hot roll, impregnation of the reinforcing resin with the thermoplastic resin is poor, and only a prepreg containing many voids can be produced. Therefore, even when formed into a molded product, voids remain as they are, and it is difficult to obtain a molded product with good characteristics. Further, a method has been proposed in which the aligned reinforcing fibers are passed through a bath of molten thermoplastic resin, but there is a drawback that the apparatus becomes large in scale. Further, the method of passing the reinforcing fibers aligned and aligned with each other through the solution of the thermoplastic resin has a problem that the size of the apparatus is large and the solvent remains in the prepreg. In the prepreg obtained by the above method, since the reinforcing material is laminated in only one direction or 0 ° and 90 °, when the prepregs are stacked, the laminating angle becomes worse. There was that. In addition, at this time, since the reinforcing fibers are simply arranged side by side, when laminated and hot pressed, the orientation of the reinforcing fibers may be partially disturbed due to the difference in thermal expansion coefficient between the reinforcing fibers and the thermoplastic resin. was there.

[0003]

The problem to be solved by the present invention is to provide a unidirectional fiber reinforced thermoplastic resin prepreg which has a good impregnation property of the matrix resin with respect to the reinforcing fibers and a good orientation of the reinforcing fibers. The present invention provides a manufacturing method which can be obtained by various devices, and further has a good impregnation property of the matrix resin with respect to the reinforcing fibers, a good orientation of the reinforcing fibers, and a fiber having a high lamination angle of the reinforcing fibers. It is an object of the present invention to provide a manufacturing method capable of obtaining a reinforced thermoplastic resin laminate with a simple device.

[0004]

In order to solve the above-mentioned problems, the present invention is to wind a reinforcing fiber and a thermoplastic resin around a metal plate, heat press the metal plate, and melt the thermoplastic resin,
It has been found that the above-mentioned problems can be solved by a method for producing a unidirectional fiber-reinforced thermoplastic resin prepreg that is integrated with a reinforcing fiber, and a flat yarn is used as a reinforcing fiber in the method for producing. This has made it possible to manufacture a unidirectional fiber-reinforced thermoplastic resin prepreg, which is particularly thin. Further, a reinforcing fiber and a thermoplastic resin are wound around a metal plate, and the reinforcing fiber and the thermoplastic resin are further wound around the metal plate in the same direction as the reinforcing fiber or in a different direction, so that at least two layers of the reinforcing fiber are formed. After that, it was found that the above problems can be solved by a method for producing a fiber-reinforced thermoplastic resin laminate in which a metal plate is hot-pressed, a thermoplastic resin is melted, and integrated with reinforcing fibers. .

A method for producing a unidirectional fiber reinforced thermoplastic resin prepreg will be described. First, a thermoplastic resin film is wound around a rectangular metal plate, and reinforcing fibers are wound around the film while applying a constant tension. At that time, the reinforcing fibers are wound in parallel at a constant pitch so as not to overlap each other. Furthermore, a film of a thermoplastic resin is wrapped around it. The wound state is shown in FIG. 1 or 2. FIG. 1 shows a cross-sectional view of a metal plate around which a film and reinforcing fibers are wound. First, the thermoplastic resin film 2 is wound around the metal plate 3, and the reinforcing fiber 1 is wound around the thermoplastic resin film 2. Furthermore, the thermoplastic resin film 2 is wound around this. The metal plate wound with the reinforcing fiber and the thermoplastic resin in this manner is sandwiched between mirror-finished plates and hot pressed. The thermoplastic resin is melted and impregnated into the reinforcing fibers, and the voids are removed by pressing. When cooled, a unidirectional fiber reinforced thermoplastic resin prepreg is obtained. The reinforcing fiber used in the present invention can be in the form of filament yarn or in the form of strand as long as it is a morphologically continuous fiber. A particularly preferred form is a so-called flat yarn in which the yarn or strand is flat. As the type, inorganic fibers such as carbon fiber, glass fiber and alumina fiber, and organic fiber such as aramid fiber can be used. Figure 1
(B) shows the case where the flat yarn 1'is used as the reinforcing fiber.

The thermoplastic resin used in the present invention may be in the form of a film or a fiber in terms of shape, and the types thereof include polyethylene terephthalate, polybutylene terephthalate, polyamide (nylon 6, nylon 66, nylon 12). , Polypropylene, polycarbonate, polyallylsulfone, polyetherimide, polyetheretherketone, etc. are used, but not limited thereto. The metal plate that can be used in the present invention has only to have a thickness that does not deform when wound with a film or a reinforcing fiber and has a smooth surface. More preferably, the surface is plated with chrome or the like.

Next, a method for manufacturing the fiber-reinforced thermoplastic resin laminate will be described. A metal plate is prepared as in the production of prepreg. A thermoplastic resin film is wound around this metal plate, and reinforcing fibers are wound around the metal plate at a constant pitch while applying tension so that they do not overlap. Further, a film and a reinforcing fiber are wound on this, this operation is repeated as many times as necessary, and finally a thermoplastic resin film is wound.
In this way, the metal plate on which the film and the reinforcing fiber are alternately wound is sandwiched between the mirror-finished plates and hot-pressed by a press machine. The thermoplastic resin film is melted and impregnated into the reinforcing fibers, and the voids are removed by heating. When cooled, a fiber-reinforced thermoplastic resin laminate is obtained. A unidirectional fiber-reinforced laminate is obtained by winding the reinforcing fibers in the same direction, and when the reinforcing fibers are wound in the alternating directions of 0 ° and 90 ° as shown in FIG. 3, a woven fabric is obtained. A bidirectional fiber-reinforced laminate is likewise obtained. As shown in FIG. 4, when the metal plate has a hexagonal shape and the reinforcing fibers are wound in three directions, a fiber-reinforced laminate having reinforcing fibers arranged in three directions can be obtained.

[0008]

According to the method for producing a prepreg of the present invention, a unidirectional fiber-reinforced thermoplastic resin prepreg having good fiber orientation and few voids can be obtained. This is because the reinforcing fibers are pressed in a state of being wound around the metal plate, so that the orientation of the fibers is not easily disturbed by the flow of the molten resin generated at the time of pressing, and the partial fibers as shown in FIG. Disturbance is also unlikely to occur. In addition, since the reinforcing fibers are sufficiently impregnated with the molten resin due to the pressurization by the press, the voids are easily removed. Especially when using the flat yarn of the reinforcing fiber,
There are few voids remaining, and the reinforcing fibers can be dispersed almost uniformly. Further, according to the method for producing a fiber-reinforced thermoplastic resin laminate of the present invention, the orientation of the reinforcing fibers in each layer is good, the orientation angle of the reinforcing fibers between layers is accurate, and a void-free laminate is obtained. To be This is because the reinforcing fibers of each layer are wrapped around the metal plate under tension, so the orientation of the fibers is less likely to be disturbed by the flow of molten resin that occurs during pressing, and due to the pressing by the press. The molten resin is sufficiently impregnated into the reinforcing fibers, and voids are easily removed. Furthermore, the laminating angle of the reinforcing fibers can be freely set by appropriately selecting the shape of the metal plate.

[0009]

【Example】

<Example 1> Method for producing unidirectional fiber reinforced thermoplastic resin prepreg (1) Material used Thermoplastic resin film Material: Polyamide film (nylon 6) Thickness: 12 μm Continuous fiber yarn for reinforcement Material: Flat yarn of carbon fiber Number of filaments: 6000 Filament diameter: 7 μm Thread count: 396 tex (396 g / 1000 m) Thread width: 4 mm (2) Method for producing unidirectional prepreg A polyamide film is wrapped around a 1 mm thick chrome-plated mirror surface plate While applying tension to the above carbon fiber, wrap it at a constant pitch so that the reinforcing fibers do not overlap. Further, a polyamide film is wound around it. In this way, the mirror surface plate wound with the reinforcing fiber and the polyamide film is sandwiched between the mirror surface plates at 270 ° C. for 2 hours.
Heat press at 0 kg / cm ² for 10 minutes. Then, it was cooled to obtain a unidirectional thermoplastic resin prepreg. The obtained prepreg had a thickness of 60 μm and a resin content of 32% by weight. Moreover, the reinforcing fibers were not disturbed, and when the cross section was enlarged, there were no voids, and the carbon fiber filaments were almost uniformly dispersed in the resin layer.

Comparative Example 1 A semi-prepreg of a unidirectional interwoven fabric of carbon fiber and polyamide was prepared under the following conditions. (1) Materials used Thermoplastic resin thread Material: Polyamide thread (nylon 6) Thread count: 150tex Reinforcing continuous fiber thread Material: Carbon fiber Number of filaments: 6000 Filament diameter: 7 μm Thread count: 396tex Thread width: 1mm ( 2) Creation of unidirectional interwoven fabric Using carbon fiber as the warp and polyamide yarn as the weft,
A unidirectional interwoven fabric was woven. The conditions for the mixed woven fabric are as follows. Weaving density 10 / 25mm Weft 17 / 25mm Carbon fiber (capacity)% 50 (3) Creation of unidirectional semi-prepreg A unidirectional interwoven cloth is passed through a hot press roll consisting of a metal roll and a rubber roll, and interwoven. A semi-prepreg was prepared by heat setting the cloth. The temperature condition of the press roll was 260 ° C., and the press pressure was 4 kgf / cm ² . The thickness of the semi-prepreg was 180 μm.

Reference Example 1 A carbon fiber / polyamide laminate was prepared under the following conditions. (1) Material used The unidirectional prepreg of Example 1 was used. (2) Molding Lamination: Five prepregs were laminated so that carbon fibers were oriented in one direction. Molding condition: 10 at 270 ° C. and 15 kgf / cm ²
Pressed for minutes. The obtained laminate has a thickness of 0.5 mm and a resin content of 3
It was 2%. Looking at the cross section of the laminate obtained in this way, it can be seen that the carbon fibers are well dispersed and there are few voids and resin pools (portions containing only resin).

Reference Comparative Example 1 Carbon fiber /
A polyamide laminate was prepared. (1) Materials used The semi-prepreg of Comparative Example 1 was used (2) Molding Lamination: Five prepregs were laminated so that the carbon fibers were oriented in one direction. Molding condition: 10 at 270 ° C. and 15 kgf / cm ²
Pressed for minutes. The obtained laminate has a thickness of 1 mm and a resin content of 32%.
Met. Moreover, it can be seen from the cross section of this laminated plate that there are voids and resin lumps.

<Example 2> A carbon fiber / polyamide laminate was molded under the following conditions. (1) Materials used Same as in Example 1 (2) Molding Lamination: In the same manner as in Example 1, polyamide film and carbon fiber were alternately wound 5 times, and finally the film was wound. The carbon fiber layers were alternately wound in the directions of 0 ° and 90 °. Therefore, the directions of the carbon fibers of the first layer and the fifth layer are the same. Molding conditions: Press molding was performed at 270 ° C. and 15 kgf / cm ² for 10 minutes. The obtained laminate has a thickness of 0.5 mm,
The resin content was 32 (weight)%. The laminated plate thus obtained has few voids and resin stagnation, and there is almost no displacement between the carbon fibers in the first and fifth layers. In addition, there is little local disorder in fiber orientation.

<Comparative Example 2> A carbon fiber / polyamide laminate was molded under the following conditions. (1) Materials used The semi-prepreg of Comparative Example 1 was used (2) Molding Lamination: Five semi-prepregs were laminated alternately in the 0 ° direction and the 90 ° direction. Molding conditions: Pressed under the same conditions as in Example 2. Looking at the cross section of the obtained laminate, it can be seen that there are voids and resin lumps. Further, it can be seen that the orientations of the carbon fibers of the first layer and the fifth layer are deviated.

[0015]

According to the prepreg manufacturing method of the present invention, the number of voids in the prepreg stage is extremely small, and
It is possible to easily obtain a unidirectional fiber-reinforced thermoplastic resin prepreg in which the orientation of reinforcing fibers is less disturbed, without requiring a large apparatus. Further, according to the method for manufacturing a laminated body of the present invention, it is possible to easily obtain a laminated body having few voids and resin stagnation, high accuracy of the laminating angle of the reinforcing fiber, and less disordered orientation of the reinforcing fiber. Furthermore, according to the method of the present invention, it is possible to freely set the laminating angle of the reinforcing fibers in the laminated body.

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[Procedure amendment]

[Submission date] September 12, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Added

[Correction content]

[Brief description of drawings]

FIG. 1 shows a cross-sectional view of a metal plate around which reinforcing fibers and a film are wound. (A) shows the case of ordinary reinforcing fibers, and (b) shows the case of flat reinforcing fibers.

FIG. 2 shows a plan view of a metal plate around which a reinforcing fiber and a film are wound.

FIG. 3 is a plan view of reinforcing fibers laminated and wound in a 0 ° direction and a 90 ° direction.

FIG. 4 is a plan view of reinforcing fibers laminated and wound in a 0 ° direction and a ± 45 ° direction.

FIG. 5A shows a laminate obtained by the production method of the present application, and FIG. 5B shows a laminate obtained by a method other than the production method of the present application.

[Explanation of symbols] 1. Reinforcing fiber 1 '. Flat reinforcing fiber 2. Thermoplastic resin film 3. Metal plate

Claims (3)

[Claims] 1. A unidirectional fiber reinforcement characterized in that a reinforcing fiber and a thermoplastic resin are wound around a metal plate, and the thermoplastic resin is melted by hot pressing the metal plate and is integrated with the reinforcing fiber. Method for producing thermoplastic resin prepreg. 2. The method for producing a unidirectional fiber-reinforced thermoplastic resin prepreg according to claim 1, wherein a flat yarn is used as the reinforcing fiber. 3. A reinforcing plate and a thermoplastic resin are wound around a metal plate, and the reinforcing fiber and the thermoplastic resin are further wound around the metal plate in the same direction as the reinforcing fiber or in a different direction, and at least two layers of the reinforcing fiber are formed. After the above, the method for producing a fiber-reinforced thermoplastic resin laminate is characterized in that the metal plate is hot-pressed to melt the thermoplastic resin and integrate it with reinforcing fibers.