JPH06297647A - Continuous fiber-reinforced composite material - Google Patents

Abstract

PURPOSE:To provide a continuous fiber-reinforced thermoplastic composite material having both excellent mechanical properties and surface functionality. CONSTITUTION:The continuous fiber-reinforced composite material uses a continuous fiber fabric as a reinforcing material and a thermoplastic resin as a matrix. The composite material has a layer which does not contain a reinforcing fiber and consist of a different resin from the resin of the reinforced matrix sayer on one surface or both surfaces of the layer containing the reinforcing fiber. In addition, the matrix resin of the layer which contains a reinforcing fiber is preferably polycarbonate or nylon 6, and a layer which does not contain a reinforcing fiber is preferably ABS.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel thermoplastic composite material. More specifically, the present invention relates to a continuous fiber-reinforced thermoplastic composite material which has both excellent mechanical properties and surface functionality.

[0002]

2. Description of the Related Art Conventionally, a composite material in a broad sense has been used in which an acrylic or polyester-based paint for increasing the surface hardness or a film is adhered to the top plate surface of a table or the wood surface. Recently, composite materials are being used for golf members. That is, in a golf member, especially in the head portion of a golf club, a composite material is used for the face surface because of the effect of broadening the sweet spot and increasing the flight distance recently, instead of the conventional metal material. Is becoming. At present, a continuous fiber reinforced composite material using a thermosetting resin is used as the composite material for the face surface.

[0003]

The continuous fiber reinforced thermosetting composite material has a history of being developed as an advanced composite material for aviation and space, and has a low viscosity of uncured resin, and therefore has a high viscosity. It is easy to impregnate the
It has the advantage of having excellent static mechanical properties. Also,
Thermosetting resins are generally rich in surface functionality and have an advantage that they can be easily coated and adhered. However, the thermosetting resin has a drawback that the resulting thermosetting composite material has insufficient dynamic mechanical properties such as impact properties and fatigue properties, because the resin after the curing reaction becomes hard and brittle. Further, thermosetting composite materials require care and labor also in machining. That is, when the continuous fiber reinforced thermosetting composite material is cut into a face shape, cracks are likely to occur, and the surface is roughened by cutting, so that there is a problem that it takes time to finish the surface of the material.

On the other hand, in the field of composite materials, attempts have been made to use a thermoplastic resin having high toughness as the matrix resin instead of the thermosetting resin. In this case, although machinability and dynamic mechanical properties are improved, impregnation into the reinforced fiber structure is difficult due to the high melt viscosity of the thermoplastic resin, and excellent mechanical properties are achieved only when a limited thermoplastic resin is used. At present, it is possible to obtain the continuous fiber-reinforced thermoplastic composite material. That is, when an ABS resin or the like, which is known as a thermoplastic resin having excellent surface functionality, is used as a matrix, excellent mechanical properties cannot be obtained, and conventional continuous fiber reinforced thermoplastic composite materials have mechanical properties There is no known material that has both surface functionality.

[0005]

DISCLOSURE OF THE INVENTION As a result of intensive studies to solve the above-mentioned drawbacks, the present inventors can achieve the object by forming a composite material into a special two-layer (or multi-layer) structure. The inventors have found that and reached the present invention.

That is, the present invention is a thermoplastic composite material comprising continuous fibers as reinforcing fibers and a thermoplastic resin as a matrix, comprising a layer containing reinforcing fibers and a layer not containing reinforcing fibers. A composite material having a two-layer (or multi-layer) structure having excellent mechanical properties and surface functionality, characterized in that the matrix resin in the layer not containing it and the layer containing the reinforcing fiber are different.

In the composite material of the present invention, the layer containing no reinforcing fiber is preferably placed outside the layer containing the reinforcing fiber. Although the layer containing no reinforcing fiber is substantially composed of only the resin, it plays a role of improving the surface functionality of the composite material, and therefore it is necessary to select a resin suitable for it. At the same time, it is necessary to form a strong bond with the layer containing the reinforcing fibers. Therefore, in the present invention, it is important to select the optimum combination of the thermoplastic resin forming the layer containing the reinforcing fibers and the thermoplastic resin forming the layer not containing the reinforcing fibers.

ABS resin is preferable as the resin used in the layer containing no reinforcing fiber in the present invention. This AB
S resin is a material having excellent surface functionality. Moreover,
Because of its moderate elasticity, it is most often used as a backup resin in the manufacture of golf heads.

On the other hand, in the present invention, nylon 6 or polycarbonate is preferable as the matrix resin forming the layer containing the reinforcing fibers.

The compatibility between ABS resin and nylon 6 or polycarbonate is not always excellent. However, our studies have surprisingly found the fact that nylon 6 or polycarbonate reinforced with continuous fibers and unreinforced ABS resin form a strong bond. Although the reason why they form a good bond is not clear, although the interface of the thermoplastic composite material obtained according to the present invention seems to be an interface, its adhesiveness is extremely strong, and repeated bending is applied. However, peeling does not occur.

In the present invention, the thickness of the layer containing no reinforcing fiber is preferably in the range of 0.05 to 1 mm. If this thickness exceeds 1 mm, peeling easily occurs due to the difference in linear expansion coefficient between the layer containing the reinforcing fiber and the layer not containing the reinforcing fiber and the strain difference when an external force is applied, which is not preferable. Moreover,
If the thickness is too large, the mechanical properties of the composite material will also deteriorate. On the other hand, if the thickness is less than 0.05 mm, defects are likely to occur in the fiber-free layer during thermal bonding of both, which is not preferable.

In the present invention, the volume-based fiber content (Vf) of the layer containing reinforcing fibers is preferably 30 to 60%. When Vf exceeds 60%, impregnation of the layer containing fibers is deteriorated, which is not preferable. On the other hand, if Vf is less than 30%, the strength of the composite material decreases, which is not preferable.

The continuous reinforcing fibers used in the present invention include:
Any type of fiber may be used as long as it has sufficient heat resistance at the melting temperature of nylon 6 or polycarbonate. For example, inorganic fibers such as carbon fiber, glass fiber, silicon carbide fiber and alumina fiber. And organic fibers such as aramid fibers. The form of the continuous reinforcing fiber used is not particularly limited, but a woven fabric such as plain weave, satin weave, and twill weave is generally used.

As a method for producing the thermoplastic composite material of the present invention, a continuous fiber-reinforced composite material sheet having nylon 6 or polycarbonate as a matrix resin is prepared in advance by a known method, and an ABS resin film is provided on both sides or one side thereof. A method of laminating and thermally bonding is preferable. At this time, the adhesive layer may be used, but it is not always necessary. The conditions used for thermal bonding are 200 at a temperature.
℃ or more and less than 250 ℃, preferably 210 ℃ or more 230 ℃
The following is used: 5-50kg / c as pressure
m ^2, preferably 5~15kg / cm ² is used.
The equipment used for joining is not particularly limited as long as the equipment can perform the joining under the above-mentioned conditions, and for example, a hot press or the like can be preferably used.

In the production of the composite material of the present invention, two or more kinds of films may be used as a film to be laminated / bonded on the surface of the composite material sheet, if necessary. For example, a polycarbonate film is laid on the surface of a composite material using nylon 6 as a matrix resin, and A
A BS resin film may be laminated and subjected to a hot press treatment. Further, as shown in the examples described later, the same resin as the surface layer resin can be fused to the surface of the composite material obtained by the present invention by injection or the like.

[0016]

The thermoplastic composite material of the present invention as described above is a material having both surface functionality and mechanical properties, and when used as a face material of a golf club head, it has a backup resin in addition to the mechanical properties. It is useful because it has excellent properties such as bondability, machinability, and finishability.

[0017]

EXAMPLES Next, examples of the present invention and comparative examples will be described in detail, but the present invention is not limited to these examples. In these examples, "CF cloth" means carbon fiber plain weave cloth (3K; CO5343) manufactured by Toray Industries, Inc.
B, 6K: CO6644B).

[0018]

COMPARATIVE EXAMPLE 1 This example shows one example of a conventionally known continuous fiber-reinforced thermoplastic composite material as a comparative example.

The CF cloth (3K and 6K products) and the polycarbonate film (thickness 130 μm) are each formed into 4 pieces.
Layers and 5 layers are laminated alternately and the laminate is set in a flat plate mold,
Using a hot press, temperature 290 ℃, pressure 30kg / c
The resin was impregnated by heating and pressing for 30 minutes under the condition of m ² . Then, it cooled to 80 degreeC and obtained the 1.2-mm-thick continuous fiber reinforced thermoplastic composite material shaping | molding board (Vf = 49%). When the surface of this molded plate was washed with acetone or methylene chloride, dissolution and white turbidity occurred, and the chemical resistance was poor.

An attempt was made to fuse the ABS resin to the surface of this plate by injection molding. That is, this molded plate was set in an adhesive mold, and ABS resin melted to 220 ° C. was injected while preheated to 130 ° C. As a result, a sufficient adhesive plate could not be obtained.

[0021]

Example 1 One ABS resin film (thickness: 200 μm) was put on each side of a CF cloth / polycarbonate composite material molding plate similar to that of Comparative Example 1, set in a flat plate mold, and a hot press was used. Then, they are fused at a temperature of 230 ° C. and a pressure of 10 kg / cm ² , cooled to 80 ° C. and taken out.
5 mm) with a total thickness of 1.5 mm and continuous fiber reinforced thermosetting composite material molded plate (Vf = 40% as a whole)
Got

As a result of observing the cross section of the molded plate obtained here, the boundary between the matrix (ABS resin / polycarbonate resin) was observed, but delamination was not observed even after repeated bending fatigue.

The surface of this different matrix molded plate was washed with the same solvent as in Comparative Example 1, but no dissolution or white turbidity was observed, and it was confirmed that the molded plate had improved chemical resistance. Further, fusion bonding of ABS resin to the surface of this molded plate was performed under the same conditions as in Comparative Example 1 above. As a result, a very strong fused material was obtained.

[0024]

Comparative Example 2 In this example, the matrix resin is nylon 6
This is a comparative example in which improvement was attempted for a composite material having a slightly difficult adhesive property.

The polycarbonate film of Comparative Example 1 was replaced with Nylon 6 film, and the other fiber structure, laminated state and molding conditions were the same as those of Comparative Example 1 described above. Using the obtained molded product (Vf = 54%), AB
Adhesion of the S resin to the ABS resin by injection was performed under the same conditions as in Comparative Example 1 above. As a result, a product with good adhesiveness was not obtained.

[0026]

Example 2 AB was formed on both sides of the molded plate according to Comparative Example 2 above.
S resin films (thickness 200 μm) were laminated and set in a flat plate mold. This was molded using a hot press under the same conditions as in Example 1, and A having a thickness of 0.15 mm was formed on both surfaces.
Composite material molded plate having BS resin layer (Vf =
44%).

As a result of observing the cross section of this molded plate, although a boundary between the matrix (ABS resin / nylon 6) was observed, delamination was not observed even after repeated bending fatigue. Further, using this different matrix molded plate, an attempt was made to bond the same ABS resin as in Example 1 by injection. The result was good, and the ABS resin could be directly injection-bonded to the molded plate.

[0028]

Comparative Example 3 For the purpose of obtaining the same effects as in Examples 1 and 2, the matrix of the composite material was molded as an ABS resin. The laminated structure was the same as that of Comparative Example 1 except that an ABS resin film (thickness 200 μm) was used instead of the polycarbonate film in the structure of Comparative Example 1. The molding conditions are hot pressing, temperature 320 ° C, pressure 3
After heating and pressurizing for 30 minutes under the condition of 0 kg / cm ^2, the solution was impregnated, cooled to 80 ° C., and taken out from the mold. As a result of cross-section observation, the obtained molded plate (Vf = 60%) was not necessarily sufficiently impregnated with ABS resin into the CF cloth, and cracks were found in the fiber bundle. When this molded plate was repeatedly bent by hand, a sound was emitted and delamination occurred. That is, A
It was difficult to mold the continuous fiber composite material with the BS resin alone.

Claims (6)

[Claims] 1. A thermoplastic composite material comprising continuous fibers as reinforcing fibers and a thermoplastic resin as a matrix, comprising a layer containing reinforcing fibers and a layer not containing reinforcing fibers,
A composite material, wherein the matrix resin in the layer containing no reinforcing fiber and the matrix resin in the layer containing reinforcing fiber are different from each other. 2. The composite material according to claim 1, wherein the thermoplastic resin of the layer containing no reinforcing fiber is an ABS resin. 3. The composite material according to claim 1, wherein the thermoplastic resin of the layer containing the reinforcing fiber is a resin containing at least one selected from nylon 6 and polycarbonate. 4. The thickness of the layer containing no reinforcing fiber is 0.0
The composite material according to claim 1, 2 or 3, which has a thickness of 5 to 1 mm. 5. The composite material according to claim 1, wherein the layer containing the reinforcing fibers has a Vf (volume-based fiber content) of 30 to 60%. 6. The method according to claim 1, wherein a layer containing reinforcing fibers and a layer not containing reinforcing fibers are prepared in advance, and the layers are thermally bonded with or without an adhesive layer. 7. The composite material described in.