JP3099656B2 - Unidirectional reinforcing fiber composite substrate and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a unidirectional reinforced fiber composite substrate used as a substrate for reinforcing fiber reinforced plastics and as a substrate for repairing fiber reinforced plastics and concrete structures.

[0002]

2. Description of the Related Art A sheet-like base material in which reinforcing fibers such as carbon fibers and glass fibers are arranged in one direction has been used as a reinforcing material for fiber-reinforced plastics in various forms.
For example, when a sheet-like base material aligned in one direction is impregnated in a resin varnish, dried, and used as a semi-cured prepreg, the reinforcing fiber is further added to the sheet-like base material aligned in one direction. When woven fabrics are laminated and used as a prepreg, a woven fabric of a reinforcing fiber or a chopped strand mat is laminated on a sheet-like base material aligned in one direction, and the layers are partially sealed with needling or resin powder. In the case of using a fixed material, and recently, as a base material for repairing aging of concrete structures such as highways and bridge piers, a woven fabric or a release fiber of reinforcing fibers is formed through a thin adhesive layer applied over the entire surface. A structure in which a reinforcing fiber sheet aligned in one direction is laminated on a support such as a mold sheet or a release film is disclosed.

However, in the case where a sheet-like base material aligned in one direction is used as a prepreg, a room temperature-curable resin cannot be used due to the problem of the life of the prepreg. Be restricted. Further, in the case of prepreg, it is necessary to wind up the film at the same time in order to prevent adhesion between layers when winding up, and when using it, there is an inconvenience that this film has to be peeled off and working. The one in which the woven fabric of the reinforcing fiber or the chopped strand mat is partially fixed to the sheet-like base material aligned in one direction does not have the problem of resin selection or the trouble of peeling off the film, and is also aligned in one direction. Although there is no problem in handling such as loosened reinforcing fibers, the adhesion between the layers is partially fixed, so that the woven fabric or mat layer must have a certain unit weight and a large weight, and the amount of The proportion of directional reinforcing fibers is reduced accordingly. Also, in particular,
Although it can be said that a woven fabric is used, there is a problem that it takes time to impregnate the resin from the opposite side of the unidirectional base material sheet.

In the case where a unidirectional substrate sheet is laminated on a support with an adhesive layer interposed therebetween, the adhesive is applied to the entire surface of the substrate sheet even though it is thin on the support surface side. It takes time to impregnate the resin from the agent layer side. Further, when a release sheet is used as a support, the cost of the base sheet is correspondingly increased, and the release sheet must be disposed of after the molding operation and the repair operation. The long time of impregnation and the disposal of the release sheet are particularly problematic for field work. When this unidirectional substrate sheet is used for repairing a concrete structure, carbon fibers are usually used as reinforcing fibers that are aligned in one direction. When impregnating the resin from the carbon fiber side, if the resin is applied with a brush or the like, the carbon fiber is only coated with a thin adhesive on the support layer side, so the surface side is fuzzed due to friction by the brush and applied. There is also a problem that work is difficult.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention solves the problem that the reinforcing fibers arranged in one direction may become loose at the time of molding fiber-reinforced plastics or repairing concrete structures. It does not impregnate the resin, has good resin impregnation, has no restriction on the choice of resin, has an excellent effect of reinforcing the reinforcing fibers arranged in one direction, has good workability in the field, and has a resin such as a brush. It is an object of the present invention to provide a unidirectional reinforcing fiber base material that does not cause fluffing on the surface when applying and impregnating with a resin.

[0006]

Means for Solving the Problems In order to solve the above problems, the inventor of the present invention has proposed a mesh sheet made of inorganic or organic fibers on both sides of a base sheet made of reinforcing fibers aligned in one direction. By the unidirectional reinforcing fiber composite substrate is bonded at the fiber portion of the mesh-like body, further, in the unidirectional reinforcing fiber composite substrate,
Unidirectional reinforcing fiber composite base material in which the reinforcing fibers aligned in one direction are carbon fibers, the mesh-like body is made of glass fiber, and the mesh-like body is adhered to both sides of a base sheet made of carbon fiber. headings that it is possible to solve the problem by a, also, these unidirectional reinforcing fiber composite matrix includes a base sheet drawer aligned reinforcing fibers in one direction
And heating the substrate sheet with a heating device.
Immediately after leaving the heating device,
Machine or laminating meshed body made of organic fiber and crimping
And the hot-melt resin in the fiber portion of the mesh-like body is
Melted and heading can be obtained by this <br/> and for bonding the base sheet and the mesh-like body.

The unidirectional reinforcing fiber composite substrate of the present invention will be described in more detail. As shown in FIG. 1, the unidirectional reinforcing fiber composite substrate 1 of the present invention has a mesh in which a mesh 3 is formed on both sides of a base sheet made of reinforcing fibers 2 aligned in one direction. It is adhered by the heat-meltable resin 5 attached around the fiber 4 for the body . As the reinforcing fibers 2 arranged in one direction used in the present invention, one type or a plurality of types of continuous fibers such as glass fibers, carbon fibers, aramid fibers, and alumina fibers are used. As a form of continuous fiber, the filament diameter is 3
μm to 30 μm monofilament 100 to 1200
It is used in a state where no strands are bundled in a non-twisted state or a lightly twisted state. As the count of one strand, a strand in the range of 50 to 1000 tex is used. Further, the mesh-like body fibers 4 used for the mesh-like body made of inorganic or organic fibers include glass fibers,
In addition to carbon fibers, aramid fibers, alumina fibers, and the like, organic fibers such as polyester fibers, nylon fibers, acrylic fibers, and vinylon fibers can be used depending on applications. The reinforcing fibers 2 aligned in one direction and the fibers 4 used in the mesh body may be of the same type or different types.

[0008] The mesh-like body of the present invention basically comprises a woven fabric having a warp and a weft, and the yarn interval is 2 to 20 m.
m. If the distance is smaller than 2 mm, it becomes an obstacle when impregnating the resin. If the distance is larger than 20 mm, the reinforcing fibers aligned in one direction are liable to fluff due to friction caused by the brush when impregnating the resin. Become. The term "woven fabric" includes a woven fabric, but naturally includes a non-woven fabric as long as it has the above configuration. For example, there is a cloth body in which a warp and a weft are overlapped with each other and a crossing point thereof is bonded with a heat-fusible resin. It can be manufactured without using a weaving machine, so the cost is lower than that of woven fabrics, and since it has a heat-fusible resin around the yarn, it bonds the base sheet of reinforcing fibers aligned in one direction. It is suitable to do. Fabrics can also be used by applying a hot-melt resin. Examples of the heat-fusible resin include a polyolefin resin having a relatively low melting point and an ethylene-vinyl acetate copolymer, but are not limited thereto. The resin adhesion amount is in the range of 7 to 25 g / m ² . If it is smaller than this, the adhesive strength is not sufficient, and if it is larger than this, impregnation of the resin is hindered or the strength properties of the molded body are likely to be reduced. As a braided cloth, 3 out of 2 axes
There is an axis, but this can also be used. The three axes are skewed yarns arranged symmetrically with respect to the warp. The mesh used in the present invention has a unit weight of 10 to 100 g / m ² . When it is less than 10 g / m ² , the strength as a support is not sufficient, and when it is more than 100 g / m ² , the ratio of the mesh-like body in the composite base material becomes large, and the unidirectionality in the molded body is increased. The effect of reinforcing the steel is reduced.
The reinforcing fibers aligned in one direction of the present invention may be arranged continuously or at intervals.

Next, the manufacturing method of the present invention will be described with reference to FIG. First, the reinforcing fibers 2 are aligned in one direction and
And the pitch is made uniform through the comb-shaped guide 6. This unidirectional base sheet is supplied to the drum cylinder 7
Heat through a heating device such as a, 7b. Immediately after the base sheet is heated above a certain temperature exits the heating device, on both surfaces of the substrate sheet, fed from the delivery system 10 mesh-like body and the thermally fusible around meshed-body fibers 4 The mesh body 3 having the resin 5 is laminated and pressed by a press roller 8 . Base sheet mesh-like member 3 on both surfaces is crimped is wound by the winding device 11, the unidirectional reinforcing fiber composite matrix 1 of the present invention is obtained. The heating device used in the production method of the present invention is preferably a drum cylinder using steam or electricity as a heat source from the viewpoint of thermal efficiency and running stability of the sheet. A heating method in which a heat source such as a sheath heater is arranged on both sides of the sheet may be used. The heating temperature of the base sheet is 30 to 30 times higher than the melting point 5 of the hot-melt resin adhered around the mesh-forming body fibers 4 constituting the mesh-forming body 3.
It is desirable to raise the temperature by 50 ° C. When the mesh body 3 is laminated on the base sheet heated to a temperature higher than the melting point, the fiber fibers 4 for the mesh body constituting the mesh body 3
The hot-melt resin that is deposited is melted around the mesh-like body 3 on both surfaces of the substrate sheet by being crimped by the press roller 8, a mesh-like-body fibers 4 constituting the mesh-like body 3 Glued at the part.

It is desirable that the temperature of the press roller 8 for pressure bonding be set at room temperature or lower than room temperature. In the case of a braided cloth, since the intersections of the yarns are fixed with a heat-fusible resin, if the temperature of the press roller 8 for pressure bonding is set to a temperature equal to or higher than the melting point of the resin, the fixing of the intersections during crimping will be broken. In addition, if the temperature of the base material is close to the melting point of the resin even in the process after the pressure bonding, the adhesion between the mesh-like body and the base material sheet is weak, and there is a possibility that partial peeling may occur. When molding a fiber-reinforced plastic using the unidirectional reinforcing fiber composite substrate of the present invention, the fiber is cut in accordance with the shape of the mold, and a required number of sheets are laminated according to the direction of the reinforcing fibers aligned in one direction. The resin is impregnated from above, the mold is closed and pressure is applied to cure the resin. The unidirectional composite base material of the present invention is uniformly aligned in one direction even when cut into an appropriate shape because the mesh-like body is bonded to both surfaces of the reinforcing fiber base sheet aligned in one direction. Reinforcing fibers do not fall apart.
In addition, since the base material itself retains flexibility because it is simply bonded by a mesh-like body, operations such as mold matching are easy.

When the resin is impregnated, the mesh is simply bonded to the surface with the fiber of the mesh, so that the resin easily penetrates the unidirectional base sheet from the opening of the mesh. Since the base sheet also has no adhesive layer or the like on its surface, the resin impregnation rate is high. In addition, when the resin is impregnated, even if the surface is rubbed with a brush, a roller, or the like, the reinforcing fibers aligned in one direction do not cause fluffing because the mesh-like body is on the surface. Importantly, the unidirectional reinforced fiber composite base material of the present invention has an advantage that it is not limited by the selection of the matrix resin because it is not prepreg-shaped and has no adhesive layer on the entire surface. In addition, the unidirectional reinforcing fiber composite base material of the present invention has a small ratio of the mesh-like body, so that the original effect of reinforcing in one direction can be enhanced. Furthermore, the one having the mesh-like body stuck on both sides has an advantage that both sides can be used in the same manner, and the faces can be freely selected. The unidirectional reinforcing fiber composite base material of the present invention can also be used for repair work of concrete structures such as highways and piers. In that case, it will be enforced on site. Cut to an appropriate size according to the location that needs repair. A primer is applied to the repaired portion, and a room temperature curing type epoxy resin, for example, is further applied. The cut composite base material is adhered, and an epoxy resin is further applied thereon with a brush. In the repair method as described above, the unidirectional reinforcing fiber composite base material of the present invention does not cause the reinforcing fibers to be loose even when cut, and has a high resin impregnation rate and a large unidirectional reinforcing effect. . No fluff on the surface when applying resin,
Both surfaces can be used in the same manner, and since a release sheet or a cover film for preventing adhesion is not required, the workability at the site and the handling property are very good.

[0012]

【Example】

<Example 1> Unidirectional substrate sheet PAN-based carbon fiber [Treca T300-6] as a reinforcing fiber
K; manufactured by Toray Industries, Inc.] to form a unidirectional base material sheet at a pitch of 5 mm. (T300-6K has a filament diameter of 7 μm and the number of bundles is 6000.) Mesh body A biaxial fabric made of glass fiber [KC0505A EV2; manufactured by Nitto Boseki Co., Ltd.] was used. The specifications of the biaxial fabric are as follows. Unit weight 22g / m ² Density (length x width) 5 / 25mm x 5 / 25m
m Adhesion amount of heat-fusible resin 10 g / m ² (The heat-fusible resin used had a melting point of 80 ° C.) Production of unidirectional reinforcing fiber composite base material Unidirectional base material sheet was heated to 130 ° C. 2 The two drum cylinders are put upside down, and immediately after leaving the cylinders, a glass fiber biaxial fabric is laminated on the upper and lower sides of the substrate sheet, pressed by a water-cooled press roller, air-cooled, and wound up. The unit weight of the composite substrate was 124 g / m ² . When the unidirectional reinforcing fiber composite base material thus obtained was impregnated with an epoxy resin, the impregnation property was good.
Also, no fuzz was found on the carbon fibers even when rubbing with a brush during impregnation.

<Example 2> Unidirectional base sheet PAN-based carbon fiber [Treca T300-1] as a reinforcing fiber
2K; manufactured by Toray Industries, Inc.] and aligned at 5 mm pitch to obtain a unidirectional substrate sheet. (T300-12
K is a filament diameter of 7 μm and the number of bundles is 12000) Mesh body A glass fiber fabric [WK-1010] as a mesh body
L; manufactured by Nitto Boseki Co., Ltd.]. Glass fiber fabrics having the following specifications were used. Unit weight 54g / m ² Density (vertical x horizontal) 10 / 25mm × 10/2
5 mm A hot-melt resin was applied to the glass fiber fabric at 8 g / m ² . Manufacture of unidirectional reinforcing fiber composite base material The unidirectional base material sheet is passed through two drum cylinders heated to 130 ° C., and immediately after leaving the cylinder, glass fiber fabrics are laminated on and under the base material sheet. Then, it is press-bonded with a water-cooled press roller, air-cooled, and wound up.
The unit weight of the composite substrate was 284 g / m ² . When the unidirectional reinforcing fiber composite base material obtained in Example 2 was impregnated with an epoxy resin, the impregnation rate was lower than that of Example 1, but at a level that would not hinder ordinary work. Also,
No fluff was found by brushing.

Example 3 The pitch of carbon fibers was 10 mm.
And a triaxial fabric [KT2
20A; manufactured by Nitto Boseki Co., Ltd.]. The specifications of the triaxial fabric are as follows. Unit weight 15 g / m ² Density (vertical × slant) 1 thread / 9 mm x 1 thread / 9 mm (the angle of the slant yarn is 60 degrees with respect to the warp yarn) Attached amount of hot melt resin 7 g / m ² The single weight of the material was 70 g / m ² . When the unidirectional reinforcing fiber composite substrate obtained in Example 3 was impregnated with an epoxy resin, the impregnating property was good. Also, no fuzz was found on the carbon fibers even when rubbing with a brush during impregnation.

<Example 4> The procedure of Example 1 was repeated except that the carbon fiber pitch was changed to 10 mm.
The single weight of the obtained composite substrate was 84 g / m ² . When the unidirectional reinforcing fiber composite base material obtained in Example 4 was impregnated with an epoxy resin, the impregnating property was good. Also, no fuzz was found on the carbon fibers even when rubbing with a brush during impregnation.

[0016]

The unidirectional reinforcing fiber composite substrate of the present invention comprises:
There is no restriction on the resin used, the resin impregnation is excellent, and the efficiency of reinforcement in one direction can be enhanced because the ratio of reinforcing fibers aligned in one direction is high. In addition, the unidirectional reinforcing fiber composite base material of the present invention has flexibility in which the reinforcing fibers aligned in one direction are not dissociated, and has excellent handling properties and on-site workability without selectivity between front and back surfaces. Is excellent. The method for producing a unidirectional reinforcing fiber composite substrate of the present invention has an advantage that it can be efficiently produced with simple equipment without using a solvent or a drying equipment.

[Brief description of the drawings]

FIG. 1 is a cut end view of a unidirectional reinforcing fiber composite base material of the present invention.

FIG. 2 is a schematic view showing an example of the production method of the present invention.

[Explanation of symbols]

1. One directional reinforcing fiber composite matrix 2. Strength fibers 3. Mesh body 4. 4. Fiber for mesh-like body Hot-melt resin 6. Comb guides 7a, 7b. Drum cylinder 8. Press roller 9. Pa over emissions 10a, 10b. 10. Mesh delivery device Winding device

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 B29B 11/16 B29B 15/08-15/14 C08J 5/04-5 / 10 C08J 5/24 E04G 23/02-23/03 JICST file (JOIS)

Claims (3)

(57) [Claims] The present invention is characterized in that a mesh-like body made of inorganic or organic fibers is bonded to both sides of a base sheet made of reinforcing fibers aligned in one direction at a fiber portion of the mesh-like body. Unidirectional reinforcing fiber composite base material. 2. The method according to claim 1, wherein the reinforcing fibers aligned in one direction are carbon fibers, the mesh-like body is made of glass fiber, and the mesh-like body is adhered to both surfaces of a base sheet made of carbon fiber. A unidirectional reinforcing fiber composite base material, comprising: 3. A base material obtained by aligning and drawing out reinforcing fibers in one direction.
Forming a sheet, heating the substrate sheet with a heating device,
Then, immediately after leaving the heating device, on both sides of the substrate sheet
Laminate a mesh of inorganic or organic fibers
Hot-melt resin attached to the fiber portion of the mesh body
Melt | dissolves and adheres the said base material sheet and this mesh-like body, The manufacturing method of the unidirectional reinforced fiber composite base material characterized by the above-mentioned.