JP2001226850A - Reinforcing fiber fabric, method for producing the same and prepreg using the reinforcing fiber fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a reinforcing fiber fabric having neither opening nor mutual convergence of filaments forming a reinforcing yarn even when a fabric such as woven fabric composed of the reinforcing yarn is impregnated with a resin solution by an immersion method. SOLUTION: This reinforcing fiber fabric 10 is constituted of a reinforcing yarn. At least a part of filaments 13 forming the reinforcing yarn is mutually partially bonded by fusion of a thermoplastic resin 14. A woven fabric woven from a warp 11 and a weft 12 composed of the reinforcing yarn may be cited as the fabric. The reinforcing fiber fabric is obtained by using a reinforcing yarn coated with a thermoplastic resin emulsion to give a fabric and then heat- treating the fabric.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing fiber cloth which exhibits excellent mechanical properties when used as a composite material such as a reinforcing material of a fiber-reinforced plastic, and a method for producing the same.

[0002]

2. Description of the Related Art Fabrics such as woven fabrics, knitted fabrics and nonwoven fabrics formed using reinforcing fibers such as glass fibers and carbon fibers are often used as reinforcing materials for plastics and concrete. In order to maximize the mechanical properties of these fabrics, when used as a reinforcing material, it is required that the yarns constituting the fabrics have no disturbance or misalignment and have a stable shape. In the production of fiber reinforced plastics,
In many cases, a prepreg in which a thermosetting resin is impregnated into a reinforcing fiber cloth is used. Examples of the impregnation method include a dipping method using a resin solution (lacquer method) and a hot melt method using a molten resin. The dipping method is a method in which a cloth is immersed in a resin solution using a resin solution obtained by dissolving a solid resin in a solvent as a resin to be used for the impregnation. When immersed in the solution, the filaments of the reinforcing fibers converge with each other, and there is a problem that the fabric is opened. Therefore, various methods have been studied to stably maintain the shape of the fabric even when the fabric is immersed in a resin solution.

As a method of stabilizing the shape of a fabric, for example, a method of covering a reinforcing fiber with a low melting point heat-fusible resin to form a woven fabric, and then heating the woven fabric to fuse the resin, Japanese Patent Laid-Open Publication No. 64-40632 discloses a method in which reinforcing fibers and thermoplastic resin fibers are simultaneously woven into a woven fabric, and then heated to soften the thermoplastic resin, solidify after melting, and then plug. is there. Also, Japanese Patent Application Laid-Open
JP-A-158207 discloses a method in which a molten resin of a thermoplastic resin is applied to a coarse-density woven fabric made of reinforcing fibers, and then the resin is solidified to bind warp yarns and weft yarns. .

[0004]

However, in the method disclosed in JP-A-64-40632, the thermoplastic resin adheres only to the auxiliary yarns arranged in parallel with the reinforcing fibers, and Although the yarns or the auxiliary yarn and the reinforcing fiber are bonded, the reinforcing fiber is not bonded at all. Therefore, when a prepreg is manufactured by impregnating the woven fabric with a resin solution by an immersion method, the reinforcing fibers converge during the impregnation, resulting in a woven fabric having openings. Also, it is extremely difficult to fill wide flat reinforcing fibers with a thread. Even with the method disclosed in Japanese Patent Application Laid-Open No. 8-158207, the reinforcing fibers converge when the molten resin is applied, resulting in a fabric having openings. Further, the woven fabric obtained by binding the warp and the weft with a thermoplastic resin has a hard feel and is inferior in flexibility. Further, when the amount of the thermoplastic resin for binding the warp and the weft increases, the surface characteristics of the fabric change, and the resin solution is hardly impregnated in the process of manufacturing the prepreg. May be.

[0005] The present invention has been made in view of the above circumstances, has no openings, and furthermore, when a prepreg is produced by impregnating a cloth such as a woven fabric made of reinforcing fibers with a resin solution by a dipping method. It is an object of the present invention to provide a reinforcing fiber cloth in which the filaments forming the fiber do not converge.

[0006]

The reinforcing fiber cloth of the present invention is a reinforcing fiber cloth composed of reinforcing fibers, wherein at least a part of the filaments forming the reinforcing fibers is fused by a thermoplastic resin. It is characterized by being partially joined to each other. The reinforcing fiber cloth is preferably a woven fabric in which warp yarns and weft yarns made of reinforcing fibers are woven. The reinforcing fiber cloth has a thermoplastic resin content of 10%.
It is preferable that the content be not more than weight%. The reinforcing fiber is preferably a carbon fiber having 1,000 to 30,000 filaments. The reinforcing fiber fabric preferably has an opening ratio of 5% or less. The woven fabric preferably has a fabric weight of 250 g / m ² or less. Further, in the woven fabric, the warp and the weft preferably have a yarn width of 3 mm or more. The reinforcing fiber cloth preferably has a yarn width change rate of the warp and the weft of 20% or less when impregnated with a resin solution for forming a prepreg. The prepreg of the present invention has a content of 30 to
It is characterized by being impregnated with 60% by weight of resin.

[0007] The method for producing a reinforcing fiber cloth according to the present invention is characterized in that a cloth is produced using reinforcing fibers to which a thermoplastic resin emulsion has been applied, and then this cloth is heat-treated. Alternatively, the method for producing a reinforcing fiber cloth of the present invention comprises:
After the application of the thermoplastic resin emulsion to the reinforcing fibers and the spreading and widening of the reinforcing fibers, a fabric is manufactured using the reinforcing fibers, and then the fabric is heat-treated. The above manufacturing method is particularly suitable when the fabric is a woven fabric obtained by weaving warp yarns and weft yarns made of reinforcing fibers. In the above manufacturing method, it is preferable that the application of the thermoplastic resin emulsion to the reinforcing fibers and the spreading and widening of the reinforcing fibers be performed continuously.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The reinforcing fiber fabric of the present invention is composed of reinforcing fibers,
At least a part of the filaments forming the reinforcing fibers are partially joined to each other by fusion of a thermoplastic resin. The reinforcing fiber is a monofilament yarn composed of one filament or a multifilament yarn composed of a plurality of filaments. Examples of the form of the fabric include a woven fabric, a knitted fabric, and a nonwoven fabric.
The reinforcing fibers used include glass fiber, carbon fiber,
Examples include inorganic fibers such as alumina fibers and organic fibers such as aramid fibers. These can be selected according to the application, but carbon fibers are particularly preferable as a reinforcing material because they are particularly lightweight, have excellent specific strength and specific elastic modulus, and are also excellent in heat resistance and chemical resistance. Further, the number of filaments of the carbon fibers is preferably 1000 to 30,000. If the number of filaments is less than 1,000, the spreading and widening treatment by false twisting may be difficult, and
When the number of the wefts exceeds the number, the widening process by spreading is easy, but special equipment for inserting the widened weft is required at the time of weaving, which may be very difficult.

When a prepreg is produced by impregnating the reinforcing fiber cloth with a resin solution by a dipping method, the thermoplastic resin joins the filaments so that the reinforcing fiber cloth does not have openings. Acrylic, polyester, and polyamide resins are used. The opening of the reinforcing fiber cloth is such that the filaments constituting the reinforcing fiber cloth converge due to the impregnation of the resin solution,
This is caused by non-uniform filament density in the reinforcing fiber fabric. However, since the filaments are partially joined by the fusion of the thermoplastic resin in this manner, the filaments do not converge even at the time of resin impregnation or the like, and since the openings do not occur in the reinforcing fiber cloth, the reinforcing fiber cloth is used. Even when used as a reinforcing material, the shape of the reinforcing fiber cloth and the mechanical properties of the reinforcing fiber cloth can be maintained. Furthermore, since the thermoplastic resin is only partially fused to the filament and does not cover the entire filament, the thermoplastic resin does not significantly affect the surface characteristics, texture, drapeability, and the like of the reinforcing fiber cloth. Therefore, even when the prepreg is manufactured by impregnating the resin solution by the dipping method, the shape and characteristics of the reinforcing fiber cloth can be maintained without lowering the impregnating property of the resin solution. There is no particular limitation on the content of the thermoplastic resin in the reinforcing fiber cloth.
% By weight or less is preferred. If the content exceeds 10% by weight, the texture of the reinforcing fiber cloth may become hard, or the impregnating property of the resin solution in producing a prepreg may decrease.

The thermoplastic resin is partially fused to all the filaments constituting the reinforcing fiber cloth, and the filaments are preferably bonded to each other by the thermoplastic resin. Only a part of the filaments constituting the reinforcing fiber cloth may be partially joined to each other. For example, in a reinforcing fiber cloth such as a woven fabric, a knitted fabric, and a nonwoven fabric, a thermoplastic resin is dispersed and fused only to a filament constituting a specific portion, and the specific portion is formed by the fusion of the thermoplastic resin. May be joined to each other. When the form of the fabric is a woven fabric, the thermoplastic resin is dispersed and fused only to the filaments constituting either the warp or the weft, and the fusion of the thermoplastic resin causes the warp or the weft to be formed. Only the filaments forming either one of the wefts may be partially joined to each other.

FIG. 1 is a perspective view schematically showing a part of the reinforcing fiber fabric 10 according to one embodiment of the present invention. The reinforcing fiber cloth 10 is a woven fabric in which a warp yarn 11 and a weft yarn 12 are woven, and each of the warp yarn 11 and the weft yarn 12 is a yarn in which a multifilament yarn of a reinforcing fiber is spread and widened into a flat shape. Each filament 13 of the multifilament yarn forming the warp yarn 11 and the weft yarn 12
In between, the thermoplastic resin 14 is partially present,
The fusion of the thermoplastic resin 14 causes the filament 13
Are joined together. In addition, the thermoplastic resin 14
Not only between filaments 13 but also between filaments 1
3 may be partially fused to the surface. In this reinforcing fiber cloth 10, the warp yarn 11 which has been spread and widened is used.
And the weft 12 usually has a yarn width of 3 mm or more and a thickness of 0.04 to 0.15 mm. If the yarn width is less than 3 mm, weaving a woven fabric having a low basis weight and an opening ratio of 5% or less may be difficult. When the thickness is less than 0.04 mm, for example, when a thermoplastic resin emulsion in which thermoplastic resin particles are dispersed in a liquid phase is used as a thermoplastic resin raw material and this emulsion is applied to the yarn, Convergence is likely to occur. On the other hand, when the thickness exceeds 0.15 mm, the thermoplastic resin emulsion does not penetrate into the fiber, and the bonding between the filaments 13 may be insufficient. Therefore, the warp yarn 11 and the weft yarn 1 having such a width and a thickness.
By weaving No. 2, a lighter weight and lower reinforcing fiber fabric 10 can be obtained. Further, when the reinforcing fiber cloth 10 is immersed in the resin solution, the change rate of the yarn width of the warp yarn 11 and the weft yarn 12 is preferably 20% or less. When the rate of change exceeds 20%, the reinforcing fabric fiber 1 is immersed.
When impregnating the resin solution with 0, the aperture increases,
In some cases, the shape of the reinforcing fiber fabric 10 is lost, and the properties as a reinforcing material cannot be exhibited. Further, the fabric weight of the reinforcing fiber cloth 10 is preferably 250 g / m ² or less. When the fabric weight is 250 g / m ² or less,
The weight of the reinforcing fiber fabric 10 is small, and a lightweight composite material can be obtained when used as a reinforcing material.

Further, the opening ratio of the reinforcing fiber cloth 10 is preferably small, more preferably 5% or less. The woven fabric having a large opening ratio has a large degree of bending of each yarn at the intersection of the warp yarn 11 and the weft yarn 12, that is, a crimp, so that the mechanical characteristics cannot be maximized, and the appearance is poor, and the commercial value is poor. When the opening ratio exceeds 5%, the openings of the reinforcing fiber cloth 10 are large, and when the reinforcing fiber cloth 10 is used as a reinforcing material, the mechanical properties may not be sufficiently exhibited. The aperture ratio here is 10% in the woven fabric.
This is the ratio of the total area of the openings where neither the warp yarn 11 nor the weft yarn 12 exists in a unit area of 0 mm × 100 mm. The area of the opening can be measured using a commercially available image processing sensor such as CV-100 manufactured by KEYENCE CORPORATION using the following formula. Aperture ratio (%) = sum of the areas of the openings (mm ² ) × 100/100
00 (mm ² )

The reinforcing fiber cloth 10 shown in FIG.
As a thermoplastic resin raw material, a thermoplastic resin emulsion in which thermoplastic resin particles are dispersed in a liquid phase is used, and can be produced as follows. First, as shown in FIGS.
Coating device 23, a dryer 24 for drying the reinforcing fibers 21, an opening and spreading device 25 for opening and widening the reinforcing fibers 21, and a winding machine 26 for winding the reinforcing fibers 21 are continuously provided. The application of the thermoplastic resin emulsion 22 to the reinforcing fibers 21 and the spreading and widening of the reinforcing fibers 21 are continuously performed by using the spread fiber applying device 20. Here, either of the application of the thermoplastic resin emulsion 22 and the spreading and widening process may be performed first. As shown in FIG. 2, when the spreading and widening process is performed after the thermoplastic resin emulsion 22 is applied, the finally obtained reinforcing fiber cloth 10 maintains a soft texture, as shown in FIG. 3. When the thermoplastic resin emulsion 22 is applied after the spread-spreading process, the yarn width of the reinforcing fibers 21 spread and spread in a flat shape is more stably fixed, and the finally obtained reinforcing fiber cloth 1 is obtained.
A value of 0 makes the shape more stable. The dryer 24
Is to evaporate the liquid component of the thermoplastic resin emulsion 22 applied to the reinforcing fibers 21 by the coating device 23,
1 for drying, and is provided next to the coating device 23.

The coating device 23 used here is as follows.
There is no particular limitation as long as the apparatus can apply the thermoplastic resin emulsion 22 to the reinforcing fibers 21 by an immersion method, a roll touch method, a roll coating method, a spray method, or the like, but as shown in FIGS. And a device capable of applying the emulsion by a roll touch method or a roll coating method. When the application roller 23a is used, the application conditions such as the width and the number of rotations of the application roller 23a, the contact length of the reinforcing fiber 21 with the application roller 23a, and the like are changed. By providing the knife 23b for adjusting the amount of the emulsion 22 attached, the amount of the thermoplastic resin emulsion 22 applied to the reinforcing fibers 21 can be easily adjusted and can be uniformly applied to the reinforcing fibers 21. The application roller 23a may be disposed below the reinforcing fibers 21 before or after opening as shown in FIGS. 2 and 3, for example, or above the reinforcing fibers 21 as shown in FIG. And may be appropriately determined according to desired application conditions and the like.

Further, as shown in FIG. 3, a wiping jig 27 for wiping the thermoplastic resin emulsion 22 once applied may be provided next to the application roller 23a. By providing such a wiping jig 27, an arbitrary portion of the thermoplastic resin emulsion 22 once applied onto the reinforcing fibers 21 is wiped, so that the thermoplastic resin 14 particles adhere to only the desired portion. Can be controlled. For example, with the application roller 23a, the reinforcing fibers 2
After the thermoplastic resin emulsion 22 is applied to the entire width direction of 1, the thermoplastic resin emulsion 22 applied to both end portions in the width direction is wiped off with a wiping jig 27, as shown in FIG. Central part 21 of
It is possible to obtain the reinforcing fibers 21 in which the thermoplastic resin particles 14 are attached only to the filaments 13a. In this way, the amount of the thermoplastic resin 14 attached and the location of the attachment may be appropriately controlled.

In the thermoplastic resin emulsion 22 used here, the particle size of the thermoplastic resin particles dispersed in the liquid phase is larger than the diameter of each filament 13 forming the warp yarn 11 and the weft yarn 12. Small ones are preferred,
Usually, it is preferably 9 μm or less. Further, the solid content concentration of the thermoplastic resin emulsion 22 is preferably in the range of 5 to 70% by weight, and more preferably 20 to 50% by weight. The polymer composition contained in the thermoplastic resin emulsion 22 is not particularly limited as long as it is a thermoplastic resin. Nylon resin, polyester resin, polybutylene terephthalate resin, urethane resin, epoxy resin, acrylic resin, polycarbonate resin, polyethylene resin And a thermoplastic resin such as a polypropylene resin. These resins are emulsified during polymerization or emulsified after polymerization, and preferably have a particle size of 9 μm or less. Above all, a thermoplastic resin obtained by emulsification at the time of polymerization can be more preferably used because the control of the particle size is easy. If necessary, two or more resin raw materials may be copolymerized and used. Further, water is preferable as the solvent of the thermoplastic resin emulsion 22, but a small amount of an organic solvent such as alcohols and acetone can be added as long as the stability of the emulsion is not impaired. When such a thermoplastic resin emulsion 22 is used, the resin solution impregnating property of the obtained reinforcing fiber fabric 10 is less likely to decrease. Further, the application amount of the thermoplastic resin emulsion here is preferably as small as possible so as to suppress the opening of the finally obtained reinforcing fiber cloth 10, and when the reinforcing fiber cloth 10 is used, the thermoplastic resin in this cloth is preferable. The content of 14 is 10% by weight or less, preferably 5% by weight or less. If the thermoplastic resin 14 has such an amount,
When prepreg is manufactured by immersing reinforcing fiber fabric 10 in a resin solution, without reducing resin solution impregnation,
The shape and characteristics of the reinforcing fiber fabric 10 can be maintained.

Examples of the spread-spreading device 25 to be used include an air spread method, a method using a vibrating bar, a roll spread method, and an ultrasonic spread method disclosed in JP-A-11-172562. And a device that can open the reinforcing fiber. As described above, the thermoplastic resin emulsion 22
Is applied, and the opening and widening processing of the reinforcing fibers 21 is spread and widened into a flat shape, and the thermoplastic resin 14 particles are brought into point contact with at least some of the filaments 13 constituting the reinforcing fibers 21. Is wound up by a winder.

FIG. 6 shows a rapier loom 30 and a heat treatment section 40 for heat-treating the fabric woven by the rapier loom 30.
FIG. 3 is a schematic configuration diagram of an apparatus provided with a winder 50 that winds the obtained woven fabric 31;
This is a reinforcing fiber cloth manufacturing apparatus for weaving using the reinforcing fibers 21 which have been coated and spread and widened as warp yarns and weft yarns, and heat-treating the obtained woven fabric 31 to manufacture the reinforcing fiber cloth 10. In the rapier loom 30, the plurality of warp yarns 11 passed through and arranged in the heald 32 are divided into upper and lower two groups by the vertical movement of the heald 32. Then, a weft (not shown) gripped by the rapier 34 is passed through the opening 33 formed between the upper and lower groups. Next, the reed 35 drives the weft thread passed through the opening 33 so as to be orthogonal to the warp thread 11. By repeating such operations, the fabric 31 is obtained. Next, in the heat treatment section 40, the obtained fabric 31 is first sandwiched between release papers 42 from above and below by a nip roller 41, and then heated by a heat roll 43. Then, the particles of the thermoplastic resin 14 attached to the filaments 13 of the reinforcing fibers are fused, whereby the filaments 13 are joined to each other to form the reinforcing fiber fabric 10. The obtained reinforcing fiber cloth 10 is wound by a winder 50.

Although the rapier loom 30 is exemplified as the loom in the reinforcing fiber cloth manufacturing apparatus of the illustrated example, other looms such as a shuttle loom, a gripper loom, and a jet loom may be used. Although there is no particular limitation on the heat treatment method, thermocompression bonding using a heat roll 43 or the like is preferable because weaving and heat treatment can be performed continuously, and strong bonding can be performed. The temperature of the heat roll 43 can be appropriately set according to the type of the thermoplastic resin 14 and the desired degree of joining.

The reinforcing fiber cloth 10 is used as a reinforcing material for a composite material such as fiber reinforced plastic. When used as a reinforcing material, the reinforcing fiber cloth 10 is formed into a prepreg by a known method such as a dipping method in which the resin is dissolved in a resin solution or a hot melt method in which a molten resin is used. ,used. Examples of the resin used for the prepreg include a thermosetting resin such as an epoxy resin, an unsaturated polyester resin, and a phenol resin, and a thermoplastic resin such as a nylon resin, a polyester resin, and a polybutylene terephthalate resin. In the prepreg, when the weight of the reinforcing fiber cloth 10 to 100 wt%, it is preferable that 30 to 60% by weight of the resin relative to the reinforcing fiber fabric 10 is impregnated. If the impregnation amount is less than 30% by weight, voids are likely to be generated, resulting in a decrease in strength,
If it exceeds 60% by weight, a resin flow may occur and a predetermined thickness may not be obtained.

Such a reinforcing fiber cloth 10 is made of a warp 11
In addition, since the filaments 13 forming the weft yarn 12 are joined to each other by fusing the thermoplastic resin 14, the shape is easily maintained. Therefore, even when the prepreg is manufactured by impregnating the reinforcing fiber cloth 10 with a resin solution by a dipping method, the filaments 13 converge, and
An opening in which the distance between the adjacent warp yarns 11 and the distance between the adjacent weft yarns 12 increases is unlikely to occur. Therefore,
The prepreg can be formed while maintaining a state where there is no opening due to the convergence of the filaments 13. In addition, since the filaments 13 are only partially fused by the thermoplastic resin 14, the surface characteristics of the filaments 13 of the reinforcing fibers are not significantly affected. Therefore, the reinforcing fiber cloth 10 entirely covered with the thermoplastic resin 14 or the filament 1 with an excessive amount of the thermoplastic resin 14 is used.
Compared with the reinforcing fiber cloth 10 in which the three are fused together, the texture is softer, and the resin fiber impregnating property is excellent when the reinforcing fiber cloth 10 is impregnated with a resin solution to produce a prepreg. In addition, since an excellent effect of preventing the opening can be obtained with a small amount of the thermoplastic resin 14, it is effective for an extremely thin cloth.

According to the method of manufacturing the reinforcing fiber cloth 10, the thermoplastic resin emulsion 22 in which the particles of the thermoplastic resin 14 are dispersed in the liquid phase is used as the thermoplastic resin 14. Without covering the entire filament 13 forming the reinforcing fiber 21 with the resin 14,
The particles of the thermoplastic resin 14 can be partially adhered. Therefore, the reinforcing fiber cloth 10 is soft in texture and has good impregnation with the resin solution when producing a prepreg.
Can be manufactured. Further, since the thermoplastic resin emulsion 22 is used as the thermoplastic resin 14, compared to the case where a resin solution in which the resin is dissolved in an organic solvent is used, the time required for post-treatment and recovery of the organic solvent is reduced. It is a low cost and economical method and is environmentally preferable. In addition, such a manufacturing method performs the application of the thermoplastic resin emulsion 22 to the reinforcing fibers 21 and the spreading and widening processing of the reinforcing fibers 21, and then manufactures a fabric using the reinforcing fibers 21. Since this is a method of heat-treating this cloth, the reinforcing fiber cloth 10 having a desired shape can be manufactured more stably and efficiently.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments. (Example 1) 12,000 filaments (fineness 720)
0 denier) carbon fiber (Pyrofil manufactured by Mitsubishi Rayon Co., Ltd.), and a thermoplastic resin emulsion in which a thermoplastic resin is dispersed in water is applied to the carbon fiber bundle by a roll touch method using a spread coating apparatus shown in FIG. It was applied to the entire lower surface. Thereafter, the reinforcing fibers were sequentially dried and spread with the apparatus shown in FIG. The yarn obtained in this manner is used as a weft, and the warp is a yarn having no thermoplastic resin emulsion applied thereto and having 12,000 filaments (fineness of 7).
200 denier) carbon fiber (Pyrofil manufactured by Mitsubishi Rayon Co., Ltd.) is used after spreading and widening, and weaving, thermocompression bonding, and winding are performed using the apparatus shown in FIG.
g / m ² of a reinforcing fiber fabric was obtained. The warp yarn width, the weft yarn width, the opening ratio, and the thermoplastic resin content of the reinforcing fiber fabric were as shown in Table 1. Further, in order to evaluate the degree of convergence of the filaments when the reinforcing fiber fabric was immersed in the resin solution, the reinforcing fiber fabric was taken out after being immersed in the acetone solution, and the yarn width before and after immersion was measured. The rate of change of the width was determined. Table 1 also shows the change rate of the yarn width in this case. Further, the reinforcing fiber woven fabric was impregnated with a 45% epoxy resin by a hot melt method, and then 16 sheets were laminated to prepare a cured plate having a thickness of 1.6 mm.
STM-D790 (L / D = 32) bending test method, AS
The three-point bending strength at 0 ° and 90 ° was evaluated based on the interlayer shear test method of TM-D2344 (L / D = 4). Table 2 shows the results.

(Example 2) The basis weight was 80 g in the same manner as in Example 1 except that the yarn coated with the thermoplastic resin emulsion, which was used as the weft, was also woven using the warp yarn.
/ M ² of the reinforcing fiber fabric. The warp yarn width, the weft yarn width, the opening ratio, and the thermoplastic resin content of the reinforcing fiber fabric were as shown in Table 1. Table 1 also shows the change rate of the yarn width obtained in the same manner as in Example 1.

Example 3 Reinforcement with a basis weight of 80 g / m ^{2 in} the same manner as in Example 2 except that carbon fibers (Pyrofil manufactured by Mitsubishi Rayon Co., Ltd.) of 3000 filaments (denier 1800 denier) were used. A fiber fabric was obtained. The warp yarn width, the weft yarn width, the opening ratio, and the thermoplastic resin content of the reinforcing fiber fabric were as shown in Table 1. Table 1 also shows the change rate of the yarn width obtained in the same manner as in Example 1.

Example 4 The basis weight was 66 g in the same manner as in Example 2 except that the amount of the thermoplastic resin emulsion applied to the carbon fiber (Pyrofil manufactured by Mitsubishi Rayon Co., Ltd.) was four times that of Example 2. / M ² of the reinforcing fiber fabric. The warp yarn width, the weft yarn width, the opening ratio, and the thermoplastic resin content of the reinforcing fiber fabric were as shown in Table 1. Table 1 also shows the change rate of the yarn width obtained in the same manner as in Example 1.

(Comparative Example 1) A reinforced fiber woven fabric having a basis weight of 80 g / m ² was obtained in the same manner as in Example 2 except that both the warp yarn and the weft yarn used were not coated with the thermoplastic resin emulsion. The warp width, weft width,
The opening ratio and thermoplastic resin content were as shown in Table 1. Table 1 also shows the change rate of the yarn width obtained in the same manner as in Example 1. Further, using this reinforcing fiber woven fabric, the bending strength and the interlaminar shear strength of the cured plate obtained in the same manner as in Example 1 were evaluated. Table 2 shows the results.

Comparative Example ² A reinforced fiber woven fabric having a basis weight of 66 g / m ² was obtained in the same manner as in Example 3 except that both the warp and the weft were not coated with the thermoplastic resin emulsion. The warp width, weft width,
The opening ratio and thermoplastic resin content were as shown in Table 1. Table 1 also shows the change rate of the yarn width obtained in the same manner as in Example 1.

[0029]

[Table 1]

As is clear from Table 1, the reinforcing fiber woven fabrics obtained in Examples 1 to 4 are all woven fabrics having a small opening ratio and almost no openings, and have a very soft hand. Even when impregnated with acetone, the yarn hardly converged, and the rate of change in the yarn width was small. These effects were remarkable in the reinforcing fiber woven fabrics of Example 2 and Example 3 in which the filaments were joined to each other by the thermoplastic resin for both the warp and the weft. Therefore, the reinforcing fiber woven fabric obtained in these examples does not converge even when impregnated with a resin solution in which a resin is dissolved by a dipping method, and is an excellent prepreg material. In contrast, in Comparative Examples 1 and 2,
A woven fabric having a small opening ratio was obtained, but the convergence of the yarn width when impregnated with acetone was large. Therefore, when the resin solution is impregnated by the immersion method, the shape of the woven fabric is disturbed, and it is not suitable for use as a prepreg material.

[0031]

[Table 2]

The reinforcing fiber woven fabric obtained in Example 1 is shown in Table 1.
As shown in Table 2, there was no convergence of the yarn width at the time of acetone impregnation, and the effect of suppressing the mesh opening was excellent. However, as shown in Table 2, the strength and impregnability of the cured plate were also reduced. It was excellent. Therefore, a decrease in mechanical strength due to joining of the filaments with the thermoplastic resin was not observed, and it was found that the reinforcing fiber woven fabric obtained in these examples was excellent as a prepreg material.

[0033]

As described above, according to the present invention, the following excellent effects can be obtained. (1) According to the reinforcing fiber cloth of the present invention, even when a prepreg is produced by impregnating a resin solution by an immersion method, filaments do not converge and the openings are less likely to occur. Is also excellent. Therefore, a prepreg can be formed while maintaining a state in which there is no opening due to convergence of filaments. In addition, since the opening can be prevented with a small amount of the thermoplastic resin, the texture of the fabric is soft and rich in drape property, and the shape stability when a prepreg is produced by impregnating the reinforcing fiber fabric with a resin solution is excellent. ing. (2) According to the production method of the present invention, since a thermoplastic resin emulsion in which thermoplastic resin particles are dispersed in a liquid phase is used as a thermoplastic resin raw material, the texture of the fabric is soft and rich in drape, and In addition, when the prepreg is manufactured by impregnating the reinforcing fiber cloth with a resin solution, a reinforcing cloth fiber having excellent shape stability can be manufactured. Furthermore, after performing the application of the thermoplastic resin emulsion to the reinforcing fibers and the spreading and widening treatment of the reinforcing fibers, a fabric is manufactured using the reinforcing fibers, so that a wide range from an extremely thin to a medium thickness can be obtained. Arbitrarily, more stably and more efficiently.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing one embodiment of a reinforcing fiber cloth.

FIG. 2 is a schematic configuration diagram illustrating an example of a spread application device.

FIG. 3 is a schematic configuration diagram showing another example of the spread application device.

FIG. 4 is a schematic configuration diagram showing another example of the spread application device.

FIG. 5 is a plan view schematically showing a reinforcing fiber in which a thermoplastic resin emulsion is attached to a filament at a central portion.

FIG. 6 is a schematic configuration diagram illustrating an example of an apparatus for producing a reinforcing fabric fiber.

[Description of Signs] 10: Reinforcing fiber cloth, 11: Warp, 12: Weft, 13 ...
Filament, 14: thermoplastic resin, 21: reinforcing fiber,
22 ... thermoplastic resin emulsion

Continued on the front page (72) Inventor Masahiko Taneike 4-160 Sunadabashi, Higashi-ku, Nagoya City, Aichi Prefecture Inside Mitsubishi Rayon Co., Ltd. Product Development Laboratory (72) Inventor Kazuya Goto 4-6-160 Sunadabashi, Higashi-ku, Nagoya City, Aichi Prefecture No. Mitsubishi Rayon Co., Ltd. Product Development Laboratory (72) Inventor Kazumasa Kawabe 43 No. 43, Tomyoji-cho, Fukui-shi, Fukui Famiel S1 Bldg. 1F 102 F F-term (reference) 4L048 AA05 AA44 AB11 AB27 AC18 BA01 CA12 CA15 DA30 DA41 EB00 EB05

Claims (13)

[Claims] 1. A reinforcing fiber fabric made of reinforcing fibers, wherein at least a part of filaments forming the reinforcing fibers are partially joined to each other by fusion of a thermoplastic resin. Reinforced fiber cloth. 2. The reinforced fiber fabric according to claim 1, wherein the woven fabric is a woven fabric of warp yarns and weft yarns made of reinforcing fibers. 3. The reinforcing fiber cloth according to claim 1, wherein the content of the thermoplastic resin is 10% by weight or less. 4. The reinforcing fiber according to claim 1, wherein the number of filaments is 1,000 to 1,000.
The reinforcing fiber cloth according to any one of claims 1 to 3, wherein the carbon fiber is 30,000 carbon fibers. 5. The reinforcing fiber cloth according to claim 1, wherein an opening ratio is 5% or less. 6. The reinforcing fiber cloth according to claim 2, wherein a fabric weight is 250 g / m ² or less. 7. The reinforcing fiber cloth according to claim 2, wherein the warp yarn and the weft yarn have a yarn width of 3 mm or more. 8. The reinforcing fiber cloth according to claim 2, wherein a change rate of the yarn width of the warp and the weft when immersed in the resin solution is 20% or less. 9. A prepreg, wherein 30 to 60% by weight of a resin is impregnated in the reinforcing fiber cloth according to any one of claims 1 to 8. 10. A method for producing a reinforcing fiber cloth, comprising producing a cloth using reinforcing fibers to which a thermoplastic resin emulsion has been applied, and then subjecting the cloth to heat treatment. 11. After applying a thermoplastic resin emulsion to reinforcing fibers and performing spreading and widening of the reinforcing fibers, a fabric is manufactured using the reinforcing fibers, and then heat treatment of the fabric is performed. A method for producing a reinforcing fiber cloth. 12. The method for producing a reinforcing fiber cloth according to claim 11, wherein the cloth is a woven fabric in which warp yarns and weft yarns made of reinforcing fibers are woven. 13. The reinforcing fiber cloth according to claim 11, wherein the application of the thermoplastic resin emulsion to the reinforcing fibers and the spreading and widening of the reinforcing fibers are continuously performed. Production method.