JP2002363855A - Opening device and opening method for fiber bundle and method for producing prepreg - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an opening device for fiber bundle which can be stably opened in high efficiency even when fiber bundle to be opened is so called fiber having high elastic modulus or carrying speed in increased and an opening method of fiber bundle utilizing the opening device and a method for producing prepreg by which prepreg obtained by impregnating a resin into opened fiber bundle is nonconventionally upgraded. SOLUTION: This opening device of fiber bundle is constituted of a plurality of rollers for transferring fiber bundle and at least two systems of mechanisms for applying vibration to the fiber bundle by changing axial center position of a vibration applying body for applying vibration to the fiber bundle to be transferred. In the opening device, a frequency f1 applying a first vibration- applying mechanism positioned on upstream side to transferring direction of the fiber bundle to the fiber bundle and a frequency f2 applying a second vibration applying mechanism positioned on downstream side to the fiber bundle each satisfy the formulas 0.5<=f1<=5 Hz and 15<=f2<=30 Hz.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber bundle opening apparatus and a fiber bundle opening method using the fiber opening apparatus.
The present invention also relates to a method for producing a prepreg in which a resin is impregnated into a spread fiber bundle spread by the spread method.

[0002]

2. Description of the Related Art A prepreg formed by drawing a plurality of single fiber bundles formed by aggregating a plurality of single fibers into a sheet shape and impregnating a matrix resin between the single fibers of the fiber bundle is a sports prepreg. It is widely used as an intermediate substrate for molding of leisure applications, aircraft materials, general industrial materials, building materials and the like.

In recent years, with the diversification of prepreg applications,
There is an increasing demand for a high-quality prepreg having a small thickness and a small thickness unevenness, or for a prepreg having a lower cost than before.

[0004] In order to produce a high-quality prepreg having a small thickness and a small thickness unevenness, a technique for opening the fiber bundle thinly and uniformly in the width direction so as not to deteriorate the quality is required. When the prepreg is manufactured in a state where the fiber bundle is not thin and not evenly spread, problems such as a decrease in the thickness of the prepreg, a large thickness unevenness, and a crack in the prepreg occur.

On the other hand, in order to produce a low-cost prepreg, it is effective to use a thicker fiber bundle.
Similarly, in order to obtain a prepreg having the same thickness as the conventional one even when a thick fiber bundle is used, a technique for opening the fiber bundle thinly and widely is also required.

Conventionally, as a method for opening a fiber bundle,
For example, as disclosed in JP-A-61-275438, after a conveyed fiber bundle is vibrated in a vertical direction by a substrate such as a reciprocating body or a rotating body, the fiber bundle is further pressed on a substrate having a curved surface. Contacting and opening the fiber;
Japanese Patent Application Laid-Open No. 2-36236 discloses a method in which a fiber bundle to be conveyed is opened by passing a part of a roller group which is an eccentric rotating body, as disclosed in JP-A-68754. As described above, when widening the tow-like material with a roller vibrating in the direction of the rotation axis, a method of applying a tension vibration to the tow-like material has been proposed.

However, according to these fiber-spreading methods, particularly when producing a prepreg having a small thickness or using a thick fiber bundle to produce a prepreg having a thickness equivalent to that of a conventional prepreg, a fiber bundle is particularly used. When it is necessary to open the fiber greatly,
It is necessary to strongly press the fiber bundle against the base or to increase the vibration frequency or the number of rotations of the base. As a result, the fiber bundle is subjected to strong abrasion, causing fluff or cutting the fiber bundle. was there. This phenomenon is particularly noticeable when the fiber bundle is a high modulus fiber. Further, in these opening methods, a sufficient opening effect could not be obtained when it was necessary to open a large fiber bundle greatly or when the conveying speed was increased. The quality of the resulting prepreg was also poor.

Various measures have been taken to solve such a problem, such as reducing the coefficient of friction of the substrate for opening the fiber bundle and using ultrasonic vibration. However, no satisfactory solution has yet been found. is the current situation.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for using a fiber bundle having a high modulus of elasticity, using a thick fiber bundle, and increasing the conveying speed. A fiber bundle opening device capable of stably and efficiently opening a wide width, a fiber bundle opening method using the present fiber bundle opening device, and impregnating a resin into the opened fiber bundle. An object of the present invention is to provide a method for producing a prepreg in which a prepreg obtained by the above method has a higher quality than ever before.

[0010]

In order to solve the above problems, the present invention has the following arrangement. That is, (1) the vibration is applied to the fiber bundle by changing the plurality of rollers that convey the fiber bundle and the axial position of the vibration applying body that applies vibration to the fiber bundle with respect to the conveyed fiber bundle. A fiber bundle opening device comprising at least two systems, wherein a first vibration imparting mechanism positioned upstream with respect to a fiber bundle transport direction imparts a vibration frequency f1 to the fiber bundle. And the frequency f2 applied to the fiber bundle by the second vibration imparting mechanism located on the downstream side satisfies the following relationships: 0.5 ≦ f1 ≦ 5 Hz and 15 ≦ f2 ≦ 30 Hz, respectively. Opening device for fiber bundles.

(2) The amplitude A1 applied to the fiber bundle by the first vibration applying mechanism and the amplitude A2 applied to the fiber bundle by the second vibration applying mechanism are respectively 20 ≦ A1 ≦ 100 mm, 1 ≦ (1) wherein A2 ≦ 5 mm is satisfied.
The fiber bundle opening apparatus according to any one of the above.

(3) The fiber according to (1) or (2), wherein the vibration imparting member that imparts vibration to the fiber bundle is a rotating roller that can freely rotate around its central axis. Bundle opening device.

(4) A fiber bundle opening method using the fiber bundle opening apparatus according to any one of (1) to (3).

(5) The fiber bundle opening method according to (4), wherein the transport speed range of the transported fiber bundle is 3 to 20 m / min.

(6) The tensile elastic modulus of the fiber bundle is 20
The fiber bundle opening method according to the above (4) or (5), which is 0 to 700 GPa.

(7) A method for producing a prepreg, comprising impregnating a resin into a fiber bundle spread by the fiber bundle opening method according to any one of (4) to (6).

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In view of the above-mentioned problems of the prior art, the present inventors have conducted intensive studies, and as a result, have identified a plurality of rollers for transporting a fiber bundle and a vibration imparting member performing an identified operation. Fiber bundle opening device having at least two systems of vibration imparting mechanisms for imparting a vibration of a given frequency to a fiber bundle, a fiber bundle opening method using such a fiber opening device, and the like. It has been found that the above problems can be solved at once by a method for producing a prepreg in which a resin is impregnated into a fiber bundle opened by the method.

That is, in the fiber bundle opening apparatus according to the present invention, the plurality of rollers for transporting the fiber bundle and the axial position of the vibration applying body for applying vibration to the fiber bundle are positioned with respect to the fiber bundle to be transported. It is configured to have at least two systems for imparting vibration to the fiber bundle by changing.

Here, the "vibration imparting member" is a member for imparting vibration to the fiber bundle to be conveyed.
For example, a rod-shaped non-rotating bar having no corner portion that damages the fiber bundle on the contact surface with the fiber bundle, a roller rotatable about an axis, and the like are included.

A plurality of rollers for transporting the fiber bundle and a roller used as the vibration imparting member have a circular cross section or extend in the direction of the rotation axis on the outer peripheral surface of the roller.
A roller with a support portion having a curvature that does not damage the fiber bundle and having a plurality of support portions for the fiber bundle protruding from the roller surface is preferably used.

When a roller with a support portion is used, when the fiber bundle comes into contact with the support portion, the fiber bundle is grasped and pushed and spread, and a state where the pushed portion comes into contact with the next support portion is formed. Is done. Thereby, even if false twist exists in the fiber bundle, the spread of twist is prevented, and the fiber bundle is stably opened.

The materials constituting the vibration imparting body and the roller for transporting the fiber bundle include stainless steel, ceramics,
General carbon steel or the like can be preferably used, but any other material can be used as long as the amount of deflection is small and the strength is not insufficient. The surface roughness of the portion in contact with the fiber bundle is 0.4 to 3.2, preferably 0.8 to 1.6 as the arithmetic average roughness Ra measured according to JIS B0601.
And a hard chrome-plated satin surface is preferred.

The fiber bundle opening apparatus according to the present invention has at least two vibration applying mechanisms for applying vibration to the fiber bundle. At least two systems mean that there are two or more sets of vibration imparting mechanisms that have independent driving sources and operate independently. Each system may be constituted by one vibration imparting body, or one system of vibration imparting mechanisms may be constituted by a plurality of vibration imparting bodies.

As the vibration applying mechanism, a mechanism for applying vibration to the fiber bundle by changing the axis of the vibration applying body with respect to the conveyed fiber bundle is preferably used. In other words, by moving on the path on which the axis of the vibration applying body is determined, the fiber bundle conveyed with the vibration applying body in all sections on the path or in some sections on the path. A mechanism that changes the path length of the fiber bundle with time by continuously or intermittently changing the path in which the fiber bundle is in contact with and conveys the fiber bundle is preferably used.

The path along which the vibration imparting member moves may be a path in which the axis circulates circularly as shown in FIG. 4, or a path perpendicular to both the axial direction and the fiber bundle transport direction as shown in FIG. A path in which the vibration applying body reciprocates in the direction is preferably used, but the reciprocating movement is more preferable because the vibration is more efficiently applied to the fiber bundle and a larger opening effect can be obtained. When the vibration imparting member reciprocates, the reciprocating motion does not necessarily have to be performed in a linear path, and is, for example, a reciprocating motion in an arcuate path centered on a certain point as shown in FIG. But there is no problem.

Of the at least two vibration imparting mechanisms,
The frequency f1 given to the fiber bundle by the first vibration imparting mechanism, which is located on the upstream side in the transport direction of the fiber bundle, is 0.5 ≦ f
1 ≦ 5 Hz, preferably 1 ≦ f1 ≦ 3
Hz. If the frequency is lower than this, the spread width of the fiber bundle tends to fluctuate with time, and if the frequency is higher than this, the fiber bundle is greatly relaxed and the yarn path is likely to be disturbed. The frequency f2 given to the fiber bundle by the second vibration imparting mechanism is 15 ≦ f2 ≦ 30 Hz,
Preferably, 15 ≦ f2 ≦ 25 Hz,
More preferably, the frequency is set to 18 ≦ f2 ≦ 23 Hz. If the frequency is lower than this, the fiber bundle opening effect is reduced, and if the frequency is higher than this, the fiber bundle is likely to be damaged.

The amplitude of the vibration imparted to the fiber bundle by the vibration imparting mechanism depends on the frequency imparted to the fiber bundle by the vibration imparting mechanism, the transport speed of the fiber bundle, or the amount of change in the path length of the fiber bundle due to the vibration. The amplitude A1 of the vibration applied to the fiber bundle by the first vibration applying mechanism and the amplitude A2 of the vibration applied to the fiber bundle by the second vibration applying mechanism are respectively 20 ≦ A1 ≦ 100 mm,
It is preferable that 1 ≦ A2 ≦ 5 mm, more preferably 40 ≦ A1 ≦ 80 mm, and 1.5 ≦ A2 ≦ 3 mm. At an amplitude smaller than this, the effect of opening the fiber bundle is reduced. If the amplitude is larger than this, the yarn path on which the fiber bundle is conveyed tends to be disturbed.

The two systems of vibration applying mechanisms can set the frequency and amplitude independently of each other. It is preferable that the first vibration applying mechanism has one vibration applying body. Second
Although the vibration imparting body of the vibration imparting mechanism may be one,
As shown in FIG. 7, it is preferable to apply a plurality of vibration imparting effects to the conveyed fiber bundle by using a plurality of vibration imparting bodies because a greater fiber opening effect can be obtained. In this case, it is preferable that a plurality of vibration applying bodies are not arranged continuously, but a transport roller is arranged between the vibration applying bodies.

Since the first vibration imparting mechanism applies a relatively large amplitude vibration to the fiber bundle, the fiber bundle is greatly relaxed, and the yarn path on which the fiber bundle is conveyed is slightly easily disturbed. In the case of producing a prepreg, there is an impregnation step of impregnating the fiber bundle with a resin after the fiber opening step, and if the influence of disturbance of the yarn path remains in this step, a good prepreg cannot be obtained. Therefore, the first vibration imparting mechanism may be disposed upstream of the second vibration imparting mechanism with respect to the transport direction of the fiber bundle so as not to influence the disturbance of the yarn path on the resin impregnation step. desirable.

In the present invention, a method of opening a fiber bundle using the above-described fiber bundle opening apparatus is employed. In this fiber opening method, the fiber bundle is opened by sequentially applying vibration to the conveyed fiber bundle by at least two systems of vibration imparting mechanisms.

Hereinafter, the opening method will be described with reference to FIG.

In the example shown in FIG.
The fiber bundle 2 pulled out of the bobbin 1 by the fiber bundle 2 comprises a first vibration imparting mechanism 5 and a second vibration imparting mechanism 6, and a fiber bundle constituted by a plurality of fiber bundle transport rollers 7. It is introduced into the opening device 4. The transport speed V of the fiber bundle 2 is preferably 3 to 20 m / min, more preferably 3 to 15 m / min, and further preferably 5 to 10 m / min.

If the fiber bundle conveying speed is higher than 20 m / min, it is difficult to obtain the fiber bundle opening effect. Also,
If the transport speed of the fiber bundle is lower than 3 m / min, the efficiency of obtaining the opened fiber bundle becomes poor, which is not preferable.

In the fiber bundle opening device 4, the fiber bundle 2
At the same time as being conveyed zigzag between the plurality of fiber bundle conveying rollers 7, the first vibration imparting mechanism 5 and the second vibration imparting mechanism are located on the downstream side with respect to the fiber bundle transport direction with respect to the fiber bundle conveying direction. Vibration is applied by the vibration applying mechanism 6.

In the fiber bundle opening method according to the present invention, the two types of vibrations having different frequencies and amplitudes are applied to the fiber bundle in this manner, whereby the fiber bundle is more effectively opened than in the prior art. be able to.

The fiber bundle repeats periodic tension fluctuations by the vibration applied from the second vibration imparting mechanism, and as a result, the bundle opening in the relaxed state due to the periodic decrease in tension causes the fiber opening effect. obtain. Furthermore, in the second vibration imparting mechanism in which the frequency of the vibration imparting body is relatively high, since the relative speed when the vibration imparting body and the fiber bundle come into contact with each other is high,
By tapping the fiber bundle, it is possible to obtain the effect of breaking the single yarn inside the fiber bundle and opening the fiber bundle.

The fiber bundle can be spread only by the vibration by the second vibration applying mechanism. However, the vibration by the first vibration applying mechanism having a lower frequency and a larger amplitude than this vibration is simultaneously generated. By giving, an even greater opening effect can be obtained.

The vibration by the first vibration imparting mechanism has a lower frequency than the vibration by the second vibration imparting mechanism, and has little effect of opening the fiber bundle by itself. By imparting the second vibration imparting function, the effect of promoting the fiber opening effect by the second vibration imparting mechanism in the relaxed state of the periodic tension fluctuation is developed. Normally, the yarn path becomes unstable as the fiber bundle continues to relax, but in this case, the relaxation state and the tension state occur alternately, so that the yarn path is not disturbed and remains stable.

The method of applying vibration to the fiber bundle by the first vibration applying body and the second vibration applying body is a method of changing the axis of the fiber bundle to be conveyed, that is, the axis of the vibration applying body. A method of moving the fiber bundle to be conveyed with the vibration imparting body in all sections on the path or in some sections on the path by moving the path on the determined path is preferably used. .

In the vibration path of the vibration applying body, when the winding angle θ of the fiber bundle 2 shown in FIG. 3 is maximized, the winding angle θ1 of the fiber bundle 2 around the first vibration applying body 51 and the second The winding angle θ2 of the fiber bundle 2 around the vibration applying body 61 is 0 ≦ θ1.
≦ 90 °, preferably 90 ≦ θ2 ≦ 180 °, more preferably 30 ≦ θ1 ≦ 60 °, 120 ≦
It is preferable that θ2 ≦ 180 °.

The winding angle θ of the fiber bundle 2 shown in FIG. 3 means the angle at which the fiber bundle 2 is wound around the vibration imparting member 51 or 52. As the vibration imparting body moves on the determined path, the winding angle θ continuously changes in a range where the fiber bundle 2 and the vibration imparting body are in contact on the path. Assuming that the maximum value of the winding angle θ of the fiber bundle 2 around the vibration applying body 51 in the continuous change of the winding angle θ is θ1 and the maximum value of the winding angle θ of the fiber bundle 2 around the vibration applying body 52 is θ2, θ1 , Θ2 is 0 ≦
It is preferable that the angles fall within the ranges of θ1 ≦ 90 ° and 90 ° ≦ θ2 ≦ 180 °. If the maximum value θ1 of the winding angle of the fiber bundle 2 around the vibration applying body 51 is larger than 90 °, the relaxation of the fiber bundle 2 becomes too large, and the yarn path becomes unstable. Further, if the maximum value θ2 of the winding angle of the fiber bundle 2 around the vibration applying body 52 is smaller than 90 °, it is difficult to obtain a sufficient opening effect. If θ2 is larger than 180 °, the yarn path is likely to be disturbed, and it becomes difficult from a mechanical point of view.

The fiber bundle to be opened by the method for opening the present fiber bundle is not particularly limited, but carbon fibers and graphite fibers are suitable. In particular, these fibers have a tensile modulus of 200 to 200%.
The effect is large in the case of 700 GPa, and the tensile elastic modulus of the fiber bundle is as high as 350 to 700 GPa. Even when the fiber bundle is easily damaged by the conventional fiber opening method, the fiber bundle is damaged. It can be opened effectively without using.

The number of single fibers constituting the fiber bundle is 1,000.
~ 100,000, more preferably 3,000
The number is preferably 0 to 18,000.

An oil agent is added to the fiber bundle to improve the sizing property of the fiber bundle, or a so-called sizing agent is added to the prepreg in order to improve the adhesion to the matrix resin. May be.

In the fiber bundle opening method according to the present invention, in order to further enhance the fiber bundle opening effect, the fiber bundle is transported in the second vibration imparting mechanism or in the fiber bundle transport direction more than the second vibration imparting mechanism. It is preferable to heat the fiber bundle to be conveyed on the upstream side of the fiber bundle. More preferably, the second
The vibration imparting mechanism portion, and both on the upstream side with respect to the fiber bundle transport direction than the second vibration imparting mechanism,
The conveyed fiber bundle is preferably heated. By heating the fiber bundle in this manner, the sizing agent or the like is in a softened state, and the fiber bundle can be more efficiently opened.

The atmosphere temperature in the heating section is 70 to 25
0 ° C., preferably 100-200 ° C., more preferably
The temperature is preferably in the range of 100 to 180 ° C.

As means for heating the fiber bundle, there are a method of blowing hot air onto the fiber bundle and a method of heating with a heater, but heating with an infrared heater is preferred.

In the method for producing a prepreg according to the present invention,
The prepreg is manufactured by impregnating the fiber bundle opened by the above-described fiber bundle opening method with a resin using a resin impregnating device. According to this method, it is possible to produce a high-quality prepreg in which the thickness unevenness is small and the resin is sufficiently impregnated in the fiber.

The resin used here and the method of impregnation with the resin are not particularly limited. Examples of the resin include thermosetting resins such as epoxy resin, vinyl ester resin, unsaturated polyester resin and phenol resin, and polyester resin. Thermoplastic resins such as resin, polyethylene resin, polycarbonate resin, polyether resin, and polyamide resin are exemplified.

Examples of the epoxy resin include bisphenol A type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, glycidylamine type epoxy resin, alicyclic epoxy resin, urethane modified epoxy resin, brominated bisphenol A type Epoxy resin or the like can be used.

These epoxy resins are not limited to single resins,
More than one type can be used in combination, and further, from liquid to solid. Usually, a curing agent is added to the epoxy resin for use.

As the impregnation method, a method of directly impregnating a fiber bundle with a resin whose viscosity has been reduced by heating, or a method of thinly and uniformly applying the above resin to a sheet such as paper or a resin film which has been subjected to a release treatment. A method in which a fiber bundle is sandwiched between two applied resin sheets and pressed with, for example, a heating roller, or a method in which the fiber bundle is impregnated with a resin whose viscosity has been reduced by dissolving with an organic solvent or the like, may be mentioned. .

[0053]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the embodiments described below.

(Example 1) The fiber bundle 2 was opened by the fiber bundle opening device 4 having the first vibration applying mechanism 5 and the second vibration applying mechanism 6 shown in FIG.

The fiber bundle 2 was continuously pulled out from the bobbin 1 by the pulling device 9 so that the fiber bundle conveying speed V was 5 m / min.

Carbon fiber [manufactured by Toray Industries, Inc.] as the fiber bundle 2
Torayca "(registered trademark) T700SC-12K (12,000 filaments)] was used.

The drawn fiber bundle 2 is introduced into a heating device 3 whose internal atmosphere temperature is heated to 100 ° C. by a 4 kW far-infrared heater, and adheres to the fiber bundle while conveying the fiber bundle 2. The sizing agent was softened.

Next, the fiber bundle 2 is moved to the first vibration imparting mechanism 5.
Then, the fiber bundle was introduced into a fiber bundle opening device 4 composed of a two-system vibration imparting mechanism including a second vibration imparting mechanism 6 and a fiber bundle transport roller 7 including a plurality of free rotating rollers having a diameter of 40 mm.

In the fiber bundle opening device 4, the vibration imparting body 51 using a free rotating roller having a diameter of 40 mm in the first vibration imparting mechanism 5 is moved in both the axial center thereof and the fiber bundle conveying direction. By reciprocating vertically, the fiber bundle 2
Was contacted from the upper surface side, and a vibration having an amplitude of the fiber bundle of 50 mm and a frequency of 2 Hz was applied. At that time, the maximum value θ1 of the winding angle θ of the fiber bundle 2 around the vibration applying body 51 was about 45 °.

Next, while the conveyed fiber bundle 2 is passed through a plurality of fiber bundle conveying rollers 7 in a zigzag manner, a vibration is applied to the fiber bundle 2 by a second vibration applying mechanism 6 installed between the roller groups. did. The second vibration applying mechanism 6 includes:
Two vibrating members 61 using a free rotating roller having a diameter of 40 mm were provided, and a free rotating roller that did not vibrate was provided between them.

The vibration imparting member 61 installed so as to come into contact with the fiber bundle from the lower surface side of the fiber bundle 2 is reciprocated in a direction perpendicular to both the axis of the fiber bundle and the direction in which the fiber bundle is conveyed. A vibration was applied so that the bundle 2 had an amplitude of 2 mm and a frequency of 20 Hz. At this time, the maximum value θ2 of the winding angle θ of the fiber bundle 2 around the vibration applying body 52 was about 160 °.

The fiber bundle 2 was evenly spread at an average width of 30 mm at the outlet of the spreader 4 with respect to a width of about 7 mm before the spread. Also, almost no fluff was observed.

The width of the fiber bundle 2 was measured visually by applying the fiber bundle to a standard ruler.

Further, the opened fiber bundle was introduced into the resin impregnating device 8 and impregnated with the resin. As a result, a uniform prepreg without cracks was obtained.

(Comparative Example 1) A fiber bundle opening device used in Example 1 was configured by removing the first vibration imparting mechanism.
The fiber bundle 2 was opened under the same conditions as in Example 1 except that the fiber bundle opening device 4 shown in FIG. 2 was used.

The fiber bundle 2 was spread only up to an average width of 25 mm at the outlet of the spreader 4 with respect to the width of about 7 mm before the spread, and the spread effect was not sufficient.

Furthermore, as a result of introducing the opened fiber bundle into the resin impregnating device 8 and impregnating the resin, cracks were found on the obtained prepreg.

[0068]

According to the fiber bundle opening apparatus and the fiber opening method using the fiber opening apparatus according to the present invention, the case where the fiber bundle is a so-called high modulus fiber or the case where a thick fiber bundle is used. Even when the fiber bundle is transported at a high speed, the fiber bundle can be stably and efficiently opened without generating fluff, etc. A fiber bundle can be obtained.

Further, by impregnating a resin into the fiber bundle opened by this opening method, a very high-quality prepreg with little unevenness in thickness can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one embodiment of a method for producing a prepreg according to the present invention.

FIG. 2 is a schematic view showing one embodiment of a method for manufacturing a prepreg according to the prior art.

FIG. 3 is a schematic view showing a winding angle of a fiber bundle around a vibration imparting body.

FIG. 4 is a schematic view illustrating one embodiment of a vibration imparting mechanism.

FIG. 5 is a schematic view showing another embodiment of the vibration imparting mechanism.

FIG. 6 is a schematic view showing still another embodiment of the vibration imparting mechanism.

FIG. 7 is a schematic view illustrating one embodiment of a second vibration imparting mechanism.

[Explanation of symbols]

 1: bobbin 2: fiber bundle 3: heating device 4: fiber bundle opening device 5: first vibration imparting mechanism 51: first vibration imparting body 6: second vibration imparting mechanism 61: second vibration imparting Body 7: Fiber bundle transport roller 8: Resin impregnating device 9: Pick-up device θ: Winding angle V: Fiber bundle transport speed

 ──────────────────────────────────────────────────続 き Continued from the front page F term (reference) 3B154 AA14 AB01 BA60 BB32 BB47 BB70 BC22 BF06 BF14 BF18 BF30 3F051 AA01 AA02 AB07 4F072 AA04 AA07 AA08 AB10 AB22 AC02 AD04 AD13 AD26 AD27 AD28 AD29 AD31 AD33 AD42 AD37 AD42 AD37 AD42 AH22

Claims (7)

[Claims] 1. A vibration is applied to a fiber bundle by changing a plurality of rollers for conveying the fiber bundle and an axial center position of a vibration applying body for applying vibration to the fiber bundle with respect to the fiber bundle to be conveyed. A fiber bundle opening device comprising at least two systems, wherein a first vibration imparting mechanism positioned upstream with respect to a fiber bundle transport direction imparts a vibration frequency f1 to the fiber bundle. And the frequency f2 applied to the fiber bundle by the second vibration imparting mechanism located on the downstream side satisfies the following relationships: 0.5 ≦ f1 ≦ 5 Hz and 15 ≦ f2 ≦ 30 Hz, respectively. Opening device for fiber bundles. 2. An amplitude A1 applied to the fiber bundle by the first vibration applying mechanism and an amplitude A2 applied to the fiber bundle by the second vibration applying mechanism are 20 ≦ A1 ≦ 100 mm and 1 ≦ A2, respectively. The fiber bundle opening device according to claim 1, wherein the fiber bundle satisfies the relationship of ≤ 5 mm. 3. The fiber bundle opening according to claim 1, wherein the vibration imparting member that imparts vibration to the fiber bundle is a rotating roller that can freely rotate around its central axis. apparatus. 4. A fiber bundle opening method, comprising using the fiber bundle opening apparatus according to claim 1. 5. The transport speed range of the transported fiber bundle is as follows:
The method for opening a fiber bundle according to claim 4, wherein the flow rate is 3 to 20 m / min. 6. A fiber bundle having a tensile elastic modulus of 200 to 7
The fiber bundle opening method according to claim 4 or 5, wherein the fiber bundle is 00 GPa. 7. A method for producing a prepreg, comprising impregnating a resin into a fiber bundle spread by the fiber bundle opening method according to any one of claims 4 to 6.