JPH05111552A - Racket frame - Google Patents

Abstract

PURPOSE:To provide a lightweight racket frame having improved mechanical strength such as torsional rupture strength and improved shock resistance and feeling while in use. CONSTITUTION:A composite layer 1' laminated with a fiber-reinforced composite resin material layer on a metal foil layer while phosphate treatment or chromate treatment is applied at least to the face of the metal foil layer on the side kept in contact with the resin material layer is provided on the outermost layer of the outer shell molding material 102 of a racket frame. The composite layer 1' has the metal foil layer, phosphate treatment or chromate treatment is applied to the metal foil layer to increase the adhesive property to the composite resin material layer, thus the racket frame is made lightweight, its mechanical strength such as torsional rupture strength is improved, its shock resistance is improved, and the feeling while in use is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frame for various rackets, such as a tennis racket or a badminton racket, in which an outer shell molding material is provided around a center material, and more particularly to the outer shell molding material. The present invention relates to a racket frame, characterized in that, as an outer layer or the like, a composite layer in which a resin material layer having or not having one or more kinds of reinforcing fibers is laminated on one or both surfaces of a metal foil layer is provided. .. More specifically, in the present invention, the metal foil layer of the composite layer is characterized in that the surface thereof is subjected to phosphate treatment or chromate treatment.

[0002]

2. Description of the Related Art Conventionally, for example, a frame for a tennis racket.
As shown in FIG. 2, the frame or the like is composed of a center material 101 and an outer shell molding material 102, but in recent years, it is said that it is lightweight and has high mechanical strength and good vibration damping characteristics. For the reason, as the outer shell molding material 102, a fiber-reinforced composite resin material using carbon fiber or glass fiber as the reinforcing fiber is used.

In such a conventional racket frame, a predetermined number of fiber reinforced prepregs for forming an outer shell molding material 102 are wound around a center material 101 formed of, for example, hard urethane foam and cured. It is produced by

At this time, in order to improve the elastic modulus, twisting and bending performance, and further to improve the vibration damping characteristics, a plurality of carbon fiber reinforced prepregs, or carbon fiber reinforced prepregs and glass fiber reinforced prepregs are used. The outer shell molding material 102 is often constructed as a hybrid structure by stacking the prepreg and the prepreg.

With such a structure, the racket frame can be made lighter and the repulsive force can be improved, the breakage can be prevented, and the vibration damping characteristics can be increased. On the other hand, recently, the weight can be simply reduced and the mechanical characteristics can be improved. Not only is it required to be increased, but also to improve the feel during use and to be fashionable (designable).

[0006]

Therefore, a fiber-reinforced composite resin layer made of prepreg or the like is provided with aluminum or steel,
A composite prepreg formed by adhering to a metal foil such as titanium by adhesion or the like, and a composite prepreg obtained by compounding this metal foil is formed in a single layer or a plurality of layers between the outermost layer of the outer shell molding material or the outer shell molding material and the center material. It has been attempted to wrap it around and use it.

According to the racket frame obtained by using the composite prepreg as described above, a metal foil layer is provided between the layers of the fiber-reinforced composite resin material by the composite prepreg laminated in a single layer to a plurality of layers. Since it is provided, it is expected that the torsional fracture strength and impact resistance of the racket frame will be improved, and that the feel (hit feeling) during use will also be improved.

However, in the case of the conventional composite prepreg, the effect of improving the mechanical strength by combining the metal foils is not sufficiently exerted, and therefore the composite prepreg is used as the outermost layer of the outer shell molding material or the core material thereof. The racket frame manufactured by being used during this period did not sufficiently improve the torsional fracture strength and impact resistance, and the feel at the time of use, such as shot feeling, was not sufficiently improved.

It has been considered to use a composite prepreg in which a simple resin layer having no reinforcing fiber is laminated on a metal foil, but similar to the above, the effect of improving the mechanical strength by compounding the metal foil is obtained. Is insufficient and causes similar problems.

An object of the present invention is to provide a racket frame made of a fiber-reinforced composite resin material, which is lightweight, has improved mechanical strength such as torsional fracture strength, and has improved impact resistance.

[0011]

The above object is achieved by a racket frame according to the present invention. In summary, the present invention provides a racket frame in which a shell molding material is provided around a core material, which has a metal foil layer and one or more reinforcing fibers laminated on one or both surfaces of the metal foil layer. Or a resin material layer not having the resin material layer, and a composite layer in which at least the surface of the metal foil layer that is in contact with the resin material layer has been subjected to a phosphate treatment or a chromate treatment in advance. The racket frame is provided in at least one of an outer layer or the outer shell molding material and a center material. Preferably, the phosphate treatment on the surface of the metal foil layer on the side in contact with the resin material layer is such that a metal salt coating film having a coating amount of 0.2 to 10 g / m ² is formed on the surface. The chromate treatment is performed so that a metal salt coating film having a coating amount of 0.01 to 0.15 g / m ² is formed on the surface. The thickness of the metal foil layer is 5 to 100 μm.
And the total thickness of the composite layer is 20 to 300 μm.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A racket frame according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the racket frame of the present invention. As shown in FIG. 1, the racket frame according to the present invention is preferably provided with a fiber reinforced prepreg for forming an outer shell molding material 102 around a center material 101 formed of hard urethane foam or the like. It is produced by winding a predetermined plurality of layers, winding the composite prepreg 1 around the outermost layer in a single layer or a plurality of layers, and curing.

That is, according to the present invention, the central member 101
And the outer shell molding material 102 provided around the center material 101
And a composite layer 1 ′ formed by laminating a metal foil layer on the fiber reinforced composite resin material layer provided on the outermost layer of the outer shell molding material 102.
A racket frame with is formed. In Figure 1,
Although the composite layer 1 ′ is provided in the outermost layer of the outer shell molding material 102, it may be provided between the center material 101 and the outer shell molding material 102, and further, the outermost layer of the outer shell molding material 102 and the center material 101.
It can be provided at any position such as between the outer shell forming material 102 and the outer shell forming material 102.

The core material 101 is preferably made of hard urethane foam or the like, and the outer shell molding material 102 is made of, for example, a plurality of carbon fiber reinforced prepregs.
Alternatively, a hybrid structure can be obtained by stacking a carbon fiber reinforced prepreg and a glass fiber reinforced prepreg.

The carbon fiber reinforced prepreg and glass fiber reinforced prepreg used as the outer shell molding material 102 may be ordinary ones, and carbon fiber (including graphite fiber) and glass fiber are used as the reinforcing fiber, respectively. As the matrix resin, a thermosetting matrix resin such as an epoxy resin, an unsaturated polyester resin, a polyurethane resin, a diallyl phthalate resin or a phenol resin can be used. Further, a curing agent and other imparting agents such as flexibility imparting agent are appropriately added so that the curing temperature is 50 to 200 ° C.

Next, the composite layer 1'characteristic of the present invention will be described in detail. FIG. 3 shows a composite layer 1'according to the present invention.
It is a composite prepreg 1 used for forming a.

The composite prepreg 1 is basically composed of a metal foil layer 5 and a fiber reinforced composite resin layer 3 having one or more kinds of reinforcing fibers 2 laminated on the metal foil layer 5, as in the conventional case. It has become. According to the present invention, the metal foil layer 5 is
At least the surface in contact with the fiber-reinforced composite resin layer 3 is previously subjected to a phosphate treatment or a chromate treatment as a chemical conversion treatment, and the fiber-reinforced composite resin layer 3 is laminated.

The fiber-reinforced composite resin layer 3 is formed by impregnating the matrix resin 6 between the reinforcing fibers, that is, the carbon fibers 2, arranged in one direction. In the present invention, this carbon fiber 2 also means graphite fiber, and graphite fiber can be used as the carbon fiber 2.

As the matrix resin 6, a thermosetting matrix resin such as an epoxy resin, an unsaturated polyester resin, a polyurethane resin, a diallyl phthalate resin or a phenol resin can be used. Further, a curing agent and other imparting agents such as flexibility imparting agent are appropriately added so that the curing temperature is 50 to 200 ° C.

As a preferred example, an epoxy resin is preferable as the matrix resin, and examples of usable epoxy resins include (1) glycidyl ether type epoxy resins (bisphenol A, F, S type epoxy resin, Novolac type epoxy resin, brominated bisphenol A type epoxy resin); (2) cycloaliphatic epoxy resin;
(3) Glycidyl ester-based epoxy resin; (4) Glycidylamine-based epoxy resin; (5) Heterocyclic epoxy resin; and one or more kinds selected from other various epoxy resins, particularly bisphenol A, F, S
Glycidyl amine epoxy resin is preferably used.
As the curing agent, amine curing agents such as dicyandiamide (DICY), diaminodiphenylsulfone (DDS), diaminodiphenylmethane (DDM); acid anhydrides such as hexahydrophthalic anhydride (HHP)
A), methylhexahydrophthalic anhydride (MHHPA)
Etc. are used, but amine-based curing agents are particularly preferably used.

The carbon fiber 2 and the matrix resin 6 in the fiber-reinforced composite resin layer 3 may be mixed in any proportion, but generally, the weight ratio of carbon fiber: matrix resin = 30 to 80:
The range of 20 to 70 is good, and preferably 40 to 75:25.
-60. When the proportion of the carbon fibers 2 is less than 30% by weight, the matrix resin 6 is hardened and the fiber reinforced composite resin layer 3 is formed.
When is used as a fiber-reinforced composite resin material, the strength of the composite resin material due to the reinforcement by the carbon fiber 2 becomes insufficient, and conversely 8
If it exceeds 0% by weight, the amount of the matrix resin 6 becomes too small, and the strength of the matrix resin 6 of the composite resin material may not be sufficient.

The metal foil layer 5 is a racket frame manufactured by using the composite prepreg 1 between the outermost layer of the outer shell molding material or the center material and the outer shell molding material, and has a torsional fracture strength and impact resistance. As described above, at least the surface of the metal foil layer 5 that is in contact with the fiber-reinforced composite resin layer 3 is for imparting mechanical strength and good usability. Chromated.

The inventors of the present invention, when manufacturing a racket frame by using a composite prepreg in which a metal foil is composited as an outermost layer of an outer shell molding material, mechanically prepare a composite prepreg by combining the metal foils. The present inventors have conducted extensive studies to obtain a racket frame having a sufficiently improved strength-enhancing effect and significantly improved mechanical strength such as torsional fracture strength and impact resistance, as well as a feel during use.

As a result, in the conventional composite prepreg, the adhesiveness of the metal foil layer to the fiber-reinforced composite resin material layer is low, and therefore, the composite prepreg is sufficiently improved in mechanical strength by combining the metal foils. The racket frame obtained by not using the composite prepreg as the outermost layer of the outer shell molding material, etc. is not sufficiently imparted with the effect of improving mechanical strength such as torsional fracture strength and impact resistance. It was found that the torsional fracture strength and the impact resistance were not sufficiently improved, and the feel at the time of use, such as the shot feeling, was not sufficiently improved.

Therefore, the adhesion of the metal foil layer to the fiber-reinforced composite resin layer may be enhanced. For that purpose, the surface of the metal foil layer which is in contact with the fiber-reinforced composite resin layer is previously treated with phosphate or chromate. After that, it may be laminated on the fiber-reinforced composite resin layer. According to this, the metal salt coating formed on the surface of the metal foil layer by the phosphate treatment or the chromate treatment is the fiber-reinforced composite resin of the metal foil layer. Since the adhesiveness with the layer is enhanced, the composite prepreg in which the metal foil is composited can sufficiently exert the effect of improving the mechanical strength such as the torsional fracture strength and the impact resistance with respect to the racket frame. It was found that the shot feel and the like can be improved.

As described above, in the present invention, at least the surface of the metal foil layer 5 which is in contact with the fiber-reinforced composite resin layer 3 is subjected to phosphate treatment or chromate treatment before being laminated on the fiber-reinforced composite resin layer 3. Specifically, at least one surface of the metal foil used as the metal foil layer is treated with a phosphate treatment solution or a chromate treatment solution, and then the fiber-reinforced composite resin layer 3 is laminated on the treated surface. Of course, when the racket frame is manufactured, the surface of the metal foil layer 5 of the composite prepreg 1 opposite to the side in contact with the fiber reinforced composite resin layer 3 also comes into contact with the fiber reinforced composite resin layer formed by a normal prepreg or the like. It is more preferable to perform phosphate treatment or chromate treatment on the opposite surface as well because the adhesive strength with the fiber-reinforced composite resin layer on the opposite surface can be improved.

As the phosphate treatment, when the metal foil is made of aluminum, zinc, titanium or the like, any phosphate treatment of zinc phosphate type or manganese phosphate type can be used. When the metal foil is iron, in addition to the above zinc phosphate-based and manganese phosphate-based treatments, iron phosphate-based phosphate treatment can be used. Although the treatment conditions such as the liquid composition of the phosphate treatment, the pH, the treatment temperature, and the treatment time can be the usual conditions, it is said that the adhesion of the metal foil layer 5 to the fiber-reinforced composite resin layer 3 is improved. From the viewpoint, it may be appropriately determined according to the type of metal foil used and the like.

Specifically, a phosphate treatment is performed to form a metal salt coating film having a coating amount of 0.2 to 10 g / m ² on the surface of the metal foil layer 5 which is in contact with the fiber reinforced composite resin layer 3. It is preferable to do this. The amount of metal salt coating is 0.2g
When it is less than / m ² , the modifying effect that contributes to the improvement of the adhesiveness due to the formation of the metal salt coating on the surface of the metal foil layer 5 is not sufficient, and the adhesion of the metal foil layer 5 to the fiber-reinforced composite resin layer 3 is insufficient. The strength does not increase. Conversely, the amount of metal salt coating is 10 g / m ²
If it exceeds, the metal salt coating becomes too thick, and this causes the adhesive strength of the metal / metal foil layer 5 with the fiber-reinforced composite resin layer 3 to decrease. Therefore, the amount of the metal salt film formed by the phosphate treatment is 0.2 to 10 g / m ² , preferably 0.5.
The range of up to 3.0 g / m ² is preferable.

Palpond L-3080 manufactured by Nippon Parker Rising Co., Ltd. is given as an example of zinc phosphate treatment.
There is the use of the zinc phosphate processing system. Assuming that the metal foil is aluminum, the conditions for the zinc phosphate treatment are as follows.

Total acidity 23 points Free acidity 0.9 points Accelerator concentration 3 points Temperature 45 ° C Immersion time 2 minutes

As the chromate treatment, a chromate treatment used for the surface treatment of a steel plate or the like can be used for almost all regardless of the type of metal foil. Similarly, the treatment conditions such as the liquid composition of the chromate treatment, the pH, the treatment temperature, and the treatment time can be the usual conditions, but the adhesion of the metal foil layer 5 to the fiber-reinforced composite resin layer 3 can be improved. From the purpose, it may be appropriately determined in consideration of the type of metal foil to be used. Specifically, a metal having a coating amount of 0.01 to 0.15 g / m ² is formed on the surface of the metal foil layer 5 that is in contact with the fiber-reinforced composite resin layer 3 by the chromate treatment, as in the case of the phosphate treatment. It is preferable to do so that a salt film (chromate film) is formed.

As an example of the chromate treatment, Zinchrome R-1415A manufactured by Nippon Parker Rising Co., Ltd.
There is a chromate treatment using. If the metal foil is made of stainless steel, the chromate treatment is as follows. That is, a treatment liquid having a concentration of 11 points of zinc chromium R-1415A was prepared and applied to a degreased and dried stainless steel foil at room temperature by a roll coater so that the application amount was 5 g / m ^2, and the applied stainless steel foil was further applied. Dry in a dryer at 80 ° C. to remove water.

The above-mentioned phosphate treatment and the like can be performed by immersing the metal foil in the treatment liquid, but the treatment may be performed on at least one side of the metal foil, and it is generally necessary to perform the treatment in a short time. Therefore, it is preferable to apply the treatment liquid to the surface of the metal foil on the side to be treated with a roll coater or the like, and there is also an advantage that it can be easily performed. Of course, it is necessary to degrease and wash the surface of the metal foil prior to the phosphate treatment, etc., and to wash and dry the metal foil immediately after the phosphate treatment, etc. It is similar to the case of processing and the like.

As the metal foil layer 5, a foil-shaped or thin plate-shaped metal sheet, or a porous foil-shaped or thin plate-shaped metal mesh such as a metal net or expanded metal can be used. The thickness of the metal foil layer 5 is 5 to 100 μm, preferably 5 to 50 μm. The thickness of the metal foil layer 5 is 5 μm
If it is less than the above range, it is too thin, and even if the metal foil layer 5 is subjected to chemical conversion treatment such as phosphate treatment, the resulting racket frame has a sufficient effect of improving mechanical strength such as torsional fracture strength and impact resistance. I can't get it. On the other hand, when it exceeds 100 μm, the thickness is too large, the workability at the time of molding is deteriorated, and the weight increase of the obtained racket frame becomes too large.

Examples of the metal material that can be used for the metal foil layer 5 include aluminum, titanium, iron, copper, nickel, nichrome, tin, lead, magnesium, gold, silver, platinum, various other metals and alloys thereof. .. For example, Showa Aluminum Co., Ltd. aluminum foil with a thickness of 30 to 50 μm,
Alternatively, the thickness of Takeuchi Metal Foil & Powder Co., Ltd. is 5 to 30 μm.
Titanium foil, stainless steel foil, high-strength steel foil, etc. can be preferably used.

The total thickness of the composite prepreg 1 is 20 to 3
It is suitable to set it to 00 μm. If the thickness of the composite prepreg 1 is less than 20 μm, it is too thin to make the prepreg 1 difficult to manufacture, and it is not practical for use as the outermost layer of the outer shell molding material of the racket frame. Also the thickness is 30
If it exceeds 0 μm, it is too thick, and it becomes difficult to form the outermost layer of the outer shell molding material with good moldability.

The composite prepreg 1 can be manufactured by any method, but a prepreg in which the matrix resin 6 is impregnated between the carbon fibers 2 arranged in one direction as the fiber reinforced composite resin layer 3 is used. When a prepreg is manufactured by the hot roll method, a metal sheet or mesh that has been subjected to the above phosphate treatment or chromate treatment is applied to the surface opposite to the surface to which the release paper is attached, and the treated surface is prepreg. The metal foil layer 5 is formed integrally with the fiber-reinforced composite resin layer 3 by pressing and adhering it on the side with, for example, a roller, so that the metal foil layer 5 can be suitably manufactured. However, the present invention is not limited to this, and for example, a prepreg as the fiber-reinforced composite resin layer 3 is independently prepared, and a metal sheet or mesh that has been subjected to a phosphate treatment or the like is later formed with an adhesive or the like. The composite prepreg 1 may be obtained by bonding and forming the metal foil layer 5.

According to the racket frame manufactured by winding one or two layers of the composite prepreg 1 around the outermost layer of the outer shell molding material, not only is it lightweight, but it is also laminated in a single layer to a plurality of layers. A metal foil layer 5 is provided between the layers of the fiber-reinforced composite resin material of the composite layer 1'by the composite prepreg 1, and the metal foil layer 5 is still treated with phosphate or chromate to provide the fiber-reinforced composite resin material. High adhesion with layers,
Since the composite effect of the metal foil layer 5 sufficiently exerts the effect of improving the mechanical strength, the torsional fracture strength and the impact resistance are sufficiently improved, and the feel (hit feeling) during use is also significantly improved. It becomes a thing.

In the above examples, the composite prepreg 1 in which the reinforcing fiber 2 shown in FIG. 3 was used as the carbon fiber was used, but the reinforcing fiber 2 is boron fiber, glass fiber, alumina fiber, silicon carbide fiber, nitriding fiber. Inorganic fibers such as silicon fibers; organic fibers such as aramid fibers, polyarylate fibers, polyethylene fibers; and metal fibers such as titanium fibers, amorphous fibers, stainless steel fibers, and the like can be arbitrarily used. Although the reinforcing fibers 2 are arranged in one direction, the reinforcing fibers 2 may be arranged in two or more directions, or may be crossed.

Further, as shown in FIG. 4, in the fiber-reinforced composite resin layer 3, a different kind of fiber 7 is used in addition to the carbon fiber 2 as the reinforcing fiber, and the composite prepreg 1 in which the reinforcing fiber is hybridized is used. You can also

The dissimilar fibers 7 are arranged in the matrix resin 6 of the fiber-reinforced composite resin layer 3 in the same direction as the carbon fibers 2 at a predetermined interval. In this embodiment, the fiber diameter is 2 to 30.
Different fiber 7 has a fiber diameter of 50 μm for carbon fiber 2 of μm
Although the diameter is large as described above, the heterogeneous fiber 7 does not have to have a large diameter. When the heterogeneous fibers 7 are used in the form of a bundle of fibers having a small fiber diameter, the strand diameter of the heterogeneous fibers 7 is converted to a diameter D ₀ = n ^1/2 × d (n: the number of bundles,
d: fiber diameter), and a strand diameter of up to 500 μm in terms of converted diameter D ₀ can be used. Further, as shown in FIG. 5, the heterogeneous fiber 7 is preferably located in the middle part of the composite prepreg, but it may be slightly deviated vertically from the center part.

Such a fiber-reinforced composite resin layer 3 can be manufactured by various methods, but two prepregs in which the carbon fibers 2 are arranged in one direction are used, and the different fibers 7 are arranged in the same direction as the carbon fibers 2 in the meantime. It is possible to manufacture very suitably by arranging them at a predetermined interval and integrating them by pressing and / or heating.

Also in the present composite prepreg 1, as usual, the reinforcing fibers are hybridized mainly for the purpose of supplementing the physical properties which are not satisfied by one kind of the reinforcing fibers or the other physical properties. Generally, carbon fibers other than carbon fibers are used, but in some cases, carbon fibers can be used as the different fibers 7 if the fiber diameter and physical properties are different from the one carbon fiber 2. As the heterogeneous fiber 7, besides carbon fiber having different physical properties, boron fiber, glass fiber,
Inorganic fibers such as alumina fibers, silicon carbide fibers, silicon nitride fibers; organic fibers such as aramid fibers, polyarylate fibers, polyethylene fibers; or metal fibers such as titanium fibers, amorphous fibers, stainless steel fibers, etc. You can

The carbon fiber 2, the dissimilar fiber 7, and the matrix resin 6 in the fiber-reinforced composite resin layer 3 may be mixed in any proportion, but generally, the weight ratio is carbon fiber: heterogeneous fiber: matrix resin = 40 to 80: 2. The range of -20: 20-60 is preferable.

Also according to the composite prepreg 1 of the present embodiment, a racket frame manufactured by using the composite prepreg 1 between the outermost layer of the outer shell molding material or the center material and the outer shell molding material similarly has a single layer to a plurality of layers. There is a metal foil layer 5 between the layers of the fiber reinforced composite resin material material laminated in layers, and the metal foil layer 5 is formed by a phosphate treatment or a chromate treatment with the fiber reinforced composite resin material layer. Since it has high adhesiveness, it is lightweight, has high torsional fracture strength, has good impact resistance, and has a good feel (hit feeling) during use.

In the above, the reinforcing fibers are hybridized by using the two kinds of reinforcing fibers 2 and 7, but the reinforcing fibers may be hybridized by using not only two kinds but three kinds or more.

FIG. 5 is a sectional view showing still another embodiment of the composite prepreg used in the present invention. In the present composite prepreg 1, in the composite prepreg 1 of FIG.
The fiber-reinforced composite resin layer 3 is characterized in that the same fiber-reinforced composite resin layer 3 using the reinforcing fibers 2 as carbon fibers is provided on the other surface opposite to the one surface provided with the fiber-reinforced composite resin layer 3. The other surface of the metal foil layer 5 on the side in contact with the fiber-reinforced composite resin layer 3 is preliminarily subjected to a phosphate treatment or a chromate treatment prior to lamination, like the one surface on the side in contact with the fiber-reinforced composite resin layer 3. Has been applied.

The racket frame produced by the composite prepreg 1 of the present embodiment also using the composite prepreg 1 as the outermost layer of the outer shell molding material has a fiber-reinforced composite resin material laminated in a single layer to a plurality of layers. There is a metal foil layer 5 between the layers,
Since the metal foil layer 5 has high adhesiveness with the fiber-reinforced composite resin material layer due to the phosphate treatment or chromate treatment,
As a result, the following advantages are achieved: lightweight, high torsional fracture strength, good impact resistance, and good feel (hit feeling) during use.

In the above, the same fiber-reinforced composite resin layer 3 having the reinforcing fibers 2 as carbon fibers is provided on both sides of the metal foil layer 5, but one fiber-reinforced composite resin layer is made of reinforcing fibers other than carbon fibers. It goes without saying that the fiber-reinforced composite resin layer may be included.

FIG. 6 is a sectional view showing still another embodiment of the composite prepreg used in the present invention. The composite prepreg 1 of the present embodiment is the composite prepreg 1 of FIG. 3, in which no reinforcing fiber is provided on one surface of the metal foil layer 5 on which the fiber reinforced composite resin layer 3 is provided and the other surface on the opposite side. The feature is that the resin layer 4 made of a simple resin is provided. The other surface of the metal foil layer 5 on the side in contact with the resin layer 4 is subjected to a phosphate treatment or a chromate treatment in advance prior to lamination, similarly to the one surface on the side in contact with the fiber reinforced composite resin layer 3. ing.

The racket frame produced by the composite prepreg 1 of the present embodiment also using the composite prepreg 1 as the outermost layer of the outer shell molding material similarly has a fiber-reinforced composite resin material laminated in a single layer to a plurality of layers. There is a metal foil layer 5 between the layers,
Since the metal foil layer 5 has high adhesiveness with the fiber-reinforced composite resin material layer due to the phosphate treatment or chromate treatment,
As a result, the following advantages are achieved: lightweight, high torsional fracture strength, good impact resistance, and good feel (hit feeling) during use.

In the above, the fiber-reinforced composite resin layer 3 is provided on one surface of the metal foil layer 5, and the resin layer 4 having no reinforcing fiber is provided on the other surface. The prepreg may not necessarily have the fiber-reinforced composite resin layer 3, and the resin layer 4 having no reinforcing fiber may be provided on both surfaces of the metal foil layer 5, or only one may be provided and the other is not provided. Instead, the configuration can be left as it is. Even in such a composite prepreg, the adhesiveness between the metal foil layer 5 and the resin layer 4 is increased by subjecting at least the surface of the metal foil layer 5 on the side in contact with the resin layer 4 to the phosphate treatment or the chromate treatment. Thus, the effect of improving the mechanical strength by combining the resin layer 4 with the metal foil layer 5 can be sufficiently exerted. Therefore, by using this in combination with ordinary carbon fiber prepreg, the racket frame has sufficiently improved double torsional fracture strength and impact resistance, and the feel (hit feeling) during use.
Will also be a significant improvement.

The present invention will be further described based on specific examples.

A composite prepreg 1 was prepared according to the present invention,
It was used in combination with a normal prepreg to produce a racket frame.

The composite prepreg 1 was prepared by laminating the reinforcing fiber composite resin layer 3 on one surface of the metal foil layer 5 shown in FIGS. 3 and 4. In order to obtain these composite prepregs 1, a method of forming a fiber reinforced composite resin layer 3 and a metal foil layer 5 integrally by sticking a metal foil by pressing at the time of preparing the prepreg as the fiber reinforced composite resin layer 3, and Two methods were tried in which a prepreg as the fiber-reinforced composite resin layer 3 was independently prepared, and then a metal foil was adhered with an epoxy adhesive to form the metal foil layer 5. The metal foil used as the metal foil layer 5 was subjected to phosphate treatment or chromate treatment on both sides in advance, and then the reinforcing fiber composite resin layer 3 was laminated.

The phosphate treatment was carried out using PALPON L-3080 manufactured by Nippon Parker Rising Co., Ltd., and the chromate treatment was carried out using Zinchrome R-1415A manufactured by Nippon Parker Rising Co., Ltd.

The racket frame thus obtained was tested for its shot feeling by actually using it with a net stretched after measuring the mechanical properties of torsional fracture strength and impact strength. For comparison, a composite prepreg that did not meet the requirements of the present invention was prepared, and used in the same manner as described above for producing a racket frame and tested. The results obtained are shown in Table 1.

[0059]

[Table 1]

In Table 1, the numerical values after the reinforcing fibers and the different kinds of fibers indicate the blending ratio (% by weight) in the fiber-reinforced composite resin layer 3, and the rest is the amount of the matrix resin. The symbol ⊚ means very good, ○ means good, Δ means slightly inferior, and × means inferior.

As the carbon fiber of the reinforcing fiber in Table 1, a PAN-based carbon fiber having a fiber diameter of 7.0 μm (trade name T-300, manufactured by Toray Industries, Inc.) was used. The different type of glass fiber is a glass fiber having a fiber diameter of 7.0 μm (made by Asahi Fiber Glass Co., Ltd., standard name E-glass), and the aramid fiber is an aramid fiber having a fiber diameter of 12 μm (made by Teijin Ltd., trade name Technora). ), The fiber diameter of polyarylate fiber is 23μ
m polyarylate fiber (Kuraray Co., Ltd., trade name Vectran) was used. An epoxy resin was used as the matrix resin. As the stainless steel foil of the metal foil, one manufactured by Takeuchi Metal Foil & Powder Co., Ltd. and having a thickness of 20 μm was used. Titanium foil manufactured by Takeuchi Metal Foil & Powder Co., Ltd. and having a thickness of 20 μm was used. Aluminum foil having a thickness of 20 μm manufactured by Takeuchi Metal Foil & Powder Co., Ltd. was used.

As shown in Table 1, in Examples 1 to 9, the composite prepreg combined with the ordinary carbon fiber prepreg was treated with zinc phosphate treatment or chromate treatment on the metal foil layer to form a fiber reinforced composite resin layer. Since the adhesiveness of the metal foil layer is high, the performance of the composite prepreg by combining the metal foil layers is fully exerted, and as a result, the resulting racket frame has improved torsional fracture strength and impact resistance, It was improved more than good, and the feeling of using the racket with a net was also better than good. On the other hand, in Comparative Examples 1 to 3, the metal foil layers of the combined composite prepreg were not subjected to the phosphate treatment or the chromate treatment, or even if the phosphate treatment was applied, the coating amount was small and the coating was effectively performed. Since there is no,
The adhesion of the metal foil layer to the fiber-reinforced composite resin layer was low, and the resulting racket frame was inferior in at least torsional fracture strength or impact resistance.

[0063]

As described above, in the racket frame of the present invention, the resin material layer with or without one or more kinds of reinforcing fibers is laminated on one or both surfaces of the metal foil layer, At least the surface of the metal foil layer, which is in contact with the resin material layer, is subjected to a phosphate treatment or a chromate treatment in advance, and the outermost layer of the outer shell molding material of the racket frame or the outer shell molding material and the central material. Since the racket frame is provided in at least one of the intervals, the racket frame is lightweight, has improved torsional fracture strength, has improved impact resistance, and has a good feel during use.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a racket frame of the present invention.

FIG. 2 is a sectional view of a conventional racket frame.

FIG. 3 is a cross-sectional view showing a composite prepreg used in the present invention.

FIG. 4 is a cross-sectional view showing another embodiment of the composite prepreg used in the present invention.

FIG. 5 is a sectional view showing still another embodiment of the composite prepreg used in the present invention.

FIG. 6 is a cross-sectional view showing still another embodiment of the composite prepreg used in the present invention.

[Explanation of symbols]

 1 composite prepreg 1'composite layer 2 reinforced fiber 3 fiber reinforced composite resin layer 4 resin layer 5 metal foil layer 6 matrix resin 7 heterogeneous fiber 101 center material 102 outer shell molding material

Claims (1)

[Claims] 1. A racket frame in which an outer shell forming material is provided around a central material, comprising a metal foil layer and one or more reinforcing fibers laminated on one or both surfaces of the metal foil layer, or A resin material layer not having, a composite layer that has been subjected to a phosphate treatment or chromate treatment in advance on at least the surface of the metal foil layer in contact with the resin material layer, the outermost layer of the outer shell molding material or A racket frame provided on at least one of the outer shell molding material and the center material.