JPH0489209A - Manufacture of prepreg - Google Patents

Abstract

PURPOSE:To enable the occurrence of voids to be prevented during laminating by the use of resin-applied paper that is coated with matrix resin in the form of stripes in the longitudinal direction of releasing paper. CONSTITUTION:When the ratio of a transporting roll 203, namely, the forwarding speed VP of releasing paper 101 relative to the speed V1 of a coating roll 201 is appropriately set, the release paper 101 can be coated with the matrix resin 102 in the form of stripes, thus obtaining coated paper 100 A. The coated paper 100 A and 100 B hold carbon fiber F, and the carbon fiber F is impregnated with resin by means of a hot press 5, so that a resin impregnation-reinforced fiber layer, namely, a prepreg layer P is formed thereon. Next, after cooling, the release paper 101 of the resin coated paper 101A is separated via a separating roller 6, instead of this, a cover film C is superimposed on the surface of the prepreg layer P via a supplying roller 8. In the prepreg 10 manufactured in this manner, the occurrence of voids is prevented during lamination, moreover, it presents a laminated prepreg that is excellent in its appearance.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. The present invention generally relates to a method for manufacturing a prepreg by sandwiching reinforcing fibers between resin-coated papers and impregnating the reinforcing fibers with resin by heating and pressurizing the reinforcing fibers. In particular, the present invention relates to a prepreg manufacturing method characterized by using resin-coated paper in which a release paper is coated with matrix resin in stripes.

In recent years, transportation fields such as aviation, space, automobiles, construction fields, etc.
Various prepregs are used in the mechanical field, sports and leisure fields, and the like.

Prepreg is produced by supplying reinforcing fibers between both resin-coated papers formed by coating the surface of release paper with matrix resin, or between resin-coated paper and simple release paper, and then hot-pressing the paper. It is manufactured by impregnating the reinforcing fibers with a resin, then peeling off one of the release papers, and then releasably attaching a cover film.

The prepreg produced in this way is generally wound into a roll, cut into a predetermined size and shape as necessary, the cover film is peeled off, and multiple sheets are usually laminated together for use. .

Conventionally, when prepregs are laminated, it is frequently seen that voids where air is trapped are formed at the laminated interface between the two prepregs 10 and 10, as shown in Figure 8. . Such voids not only cause deterioration of physical properties such as lowering the strength of the prepreg, but also, especially when carbon fiber is used as the reinforcing fiber, the void portion becomes bulky and is unfavorable in terms of appearance. , it is desirable to prevent the generation of polar capoids.

As a solution to this problem, attempts have been made to generate voids by vacuum bowing the prepregs when they are laminated by pressurizing and heating them in an autoclave.This method is an extremely effective method. However, it is not possible to completely suppress the generation of voids.

The present inventors conducted many research experiments to solve this problem, and as a result, as shown in FIG. 7, the surface of the prepreg 10 after peeling off the cover film 103 is extremely smooth. It was found that when both prepregs with good smoothness are stacked on top of each other, there is no way for the air trapped at the interface between the layers to escape, resulting in voids. Therefore, the present inventors created grooves (stripe) S along the axial direction of the reinforcing fibers on the surface of the prepreg, as shown in FIGS. found that the problem was solved.

In other words, as shown in FIGS. 9 and 10, when the prepregs with stripes, the so-called striped prepregs 10, are used to stack the layers, even when the prepregs are stacked, air may flow to the interface between the layers. Even if such air is taken in, as the prepreg is stacked from one end to the other end, it is guided to the other end through the stripes S formed along the longitudinal direction of the reinforcing fibers, and is led to the outside. As a result, voids were formed at the laminated interface between both prepregs and no longer remained as in the conventional case.

The present invention has been made based on this new knowledge.

Therefore, an object of the present invention is to provide a method for manufacturing striped prepregs that prevents the generation of voids when stacking prepregs.

The above-mentioned objects are achieved by the method for producing a striped prepreg according to the present invention. In summary, the present invention provides the first
and a second resin-coated paper, or between the first or second resin-coated paper and a simple release paper, and impregnate the reinforcing fibers with a resin by hot pressing means, and then In a prepreg manufacturing method in which one release paper is peeled off and then a cover film is releasably attached, the first resin-coated paper and/or the second resin-coated paper cover the surface of the release paper. The method for producing a prepreg is characterized in that the release paper is coated with a matrix resin in stripes along the longitudinal direction.

The resin-coated paper coated with the matrix resin in stripes is coated with a coating roll rotating at a speed (1) of (1), so that VP/VP≦0.
To the release paper that is conveyed oppositely at a speed VP that satisfies 8,
It is produced by coating a matrix resin of a predetermined viscosity in a stripe form, or (2) by a coating roll rotating at a speed of 2, the coating roll is coated with VP/Vp = Q, 9 to 1.2. It is manufactured by uniformly coating a matrix resin of a predetermined viscosity on a release paper that is conveyed oppositely at a speed Vp, and then forming the coating film into a stripe shape using a comb-like stripe forming member. , or (3) by a stepped coating roll rotating at a speed V+, with respect to the coating roll V l /
V P =0.

It is manufactured by coating a matrix resin of a predetermined viscosity in stripes on release papers that are conveyed in opposite directions at a speed VP satisfying 9 to 1.2.

East JL Example Hereinafter, the method for manufacturing a striped prepreg according to the present invention will be explained in detail with reference to the drawings.

According to the present invention, the striped prepreg has reinforcing fibers between both resin-coated papers formed by coating the surface of a release paper with a matrix resin, or between a resin-coated paper and a simple release paper. The reinforcing fibers are supplied and impregnated with resin using hot press means, and then one of the release papers is peeled off and a cover film is releasably attached to the reinforcing fibers.
Although conventional prepreg manufacturing equipment can be suitably used, the manufacturing method of the present invention is characterized by the resin-coated paper used.

In other words, the resin coated paper 100 used in the present invention
As shown in the figure, the surface of release paper 101 is coated with matrix resin 102 in stripes along its longitudinal direction. Further, a cover film 103 is attached to the surface as necessary for storage, and is peeled off when used.

The coating shape of the striped matrix resin on the release paper 101, that is, the thickness (t), the convergence (Wc), and the interval (Wt) can be changed arbitrarily, and the thickness (1) is generally 20 to 100 μm. , width (Wc) is 2 to 3 mm,
and the spacing (WE) is appropriately selected within the range of 0.3 to 1 mm.

Next, a method for manufacturing such resin-coated paper 100 will be explained.

FIG. 2 shows a schematic configuration of a manufacturing apparatus for manufacturing resin-coated paper 100 used in the present invention. In this embodiment, the resin-coated paper manufacturing apparatus includes first and second coated rollers 201 and 202 arranged oppositely, and a first coated roller 201.
' A release paper conveyance roll 203 is provided, which is disposed opposite to '.

A matrix resin storage tank 204 is arranged on one side of the first and second coating rollers 201, 202, and supplies matrix resin 102 with an appropriate viscosity to the nip portion 205 of the first and second coating rollers 201, 202. . Also, release paper 10
1 is wound from the supply roll 206 around the outer periphery of the release paper transport roll 203, and then wound onto the take-up roll 208 via the guide roll 207.

With the above configuration, the first and second coating Erol 201.202
are in the same direction, i.e. clockwise in Fig. 2, respectively VP,
The release paper 101 is rotated at a speed Vp and is conveyed at a speed Vp in a direction opposite to the first coating roll 201 by a conveyance roll 203 that rotates clockwise in FIG. Therefore, the nip portion 2 of the first and second coating rollers 201 and 202
Matrix resin 102 supplied to 05 at an appropriate viscosity
is transferred to the release paper 101 side by the first coating roller 201, and the surface of the release paper 101 is coated with a coating film of a predetermined thickness. On the other hand, the matrix resin on the surface of the second coating roll 202 is removed by a doctor blade 209 placed adjacent to the roll 202 and returned to the storage tank 204. Preferably, the storage tank 204 is provided with heating means (not shown) for maintaining the matrix resin 102 at a predetermined temperature.

The release paper 101 on which the matrix resin coating film 102 of a predetermined thickness has been formed is then pasted with the cover film 103 using the roll 210, and then wound onto the take-up roll 208 as described above.

In the resin-coated paper manufacturing apparatus having the above-mentioned configuration, the present inventors have determined that the transport roll 20 is
3, that is, the ratio of the feed speed vP of the release paper 101 (v, /vp
) instead of 0, 9 to 1.2, which is conventionally done.
．． By making it 8 or less, that is, v + / v
It has been found that by setting p≦0.8, it is possible to coat the matrix resin 102 on the release paper 101 in stripes as shown in FIG.

To give a concrete example of its configuration, ・Diameter of first coating roller 500mm Peripheral speed (
V+) 120mm/sec・Diameter of second coating Erol 300mm Peripheral speed (Vt) 17
mm/sec・Gap between first coated roller and second coated roller 50 μm・Diameter of conveyance roll 400 mm・Speed of release paper (
Vp) 170mm/sec・Matrix resin Epoxy resin viscosity (70℃) 2
At 10,000 centipoise, the thickness (1) is 50 μm, the width (WE) is 2-3 mm, and the spacing (WE) is 0.3 as shown in Figure 1.
A resin-coated paper 100 of ~1 mm was obtained. In this example, dicyandiamide was added to the epoxy resin as a curing agent.

Using this resin-coated paper, a striped prepreg using carbon fiber as reinforcing fiber was manufactured. The manufacturing method will be explained with reference to FIG.

In this embodiment, the carbon fibers F drawn out from the krill stand, ie, the fiber supply means 1, are passed between the supply rollers 2a and 2b. On the other hand, resin coated paper 100 constructed according to the present invention is wound around resin coated paper winders 3 and 4.
A and 100B are drawn out to supply rollers 2a and 2b, and sandwich the carbon fibers F. At this time, resin coated paper 1
00A and 100B are fed so that their respective matrix resins 101 face each other and are joined.

Resin coated paper 100A, carbon fiber F and resin coated paper 100
The layered body consisting of B is supplied to the hot press means 5, and the carbon fibers F are impregnated with resin to form a resin-impregnated reinforcing fiber layer,
That is, a prepreg layer P is formed.

Next, after being cooled to a predetermined temperature by a cooling means (not shown) as necessary, the resin-coated paper 1 is removed via a peeling roller 6.
The release paper 1OIA of 00A is peeled off, and instead, the cover film C pulled out from the cover film winder 7 is superimposed on the surface of the prepreg layer 2 via the supply roller 8. The prepreg 10 manufactured in this way is wound up into a roll around the winding shaft 9. In this example, the content of matrix resin in prepreg 10 is 35% by weight.
Met.

When the cover film of the prepreg 10 manufactured through the series of manufacturing steps described above was then peeled off and the surface was observed, as shown in FIG. Grooves, ie, stripes S, were formed.

Further, the prepregs were cut into predetermined dimensions and laminated in an autoclave while being evacuated, but no voids were generated at the lamination interface.

In the above manufacturing method, resin coated paper 100A and 100B are
Although the explanation has been made assuming that the resin-coated paper 100 as shown in FIG.
B may be a conventional resin-coated paper in which a release paper is uniformly coated with a matrix resin, or may be a mere release paper not coated with a matrix resin.

The resin-coated paper 100 constructed according to the present invention as shown in FIG. 1 can also be manufactured by the method shown in FIGS. 4 and 5.

That is, according to this embodiment, the same manufacturing apparatus as shown in FIG. 2 is used, but the speed of the first coating roller 201 is
The ratio (VP/VP) of the feed speed of the transport roll 203, that is, the release paper 101 to 1, is the same as before (, V l
/V P ~0, set to 9 to 1.2, and the matrix resin 102 is uniformly coated on the release paper 101.

According to this embodiment, as shown in FIG. 5, a comb-like stripe forming member 220 having a large number of protrusions 221 is disposed across the release paper 101 on the release paper,
Therefore, the matrix coating film 102 uniformly coated on the surface of the release paper 101 is coated on the stripe forming member 22.
0, it is formed into a striped shape as shown in FIG.

Therefore, the stripe forming member 220 is formed in a complementary shape to the desired striped matrix resin coating shape of the resin-coated paper, and has a thickness (T) of 3 mm, for example.
A metal plate such as a styrene-free steel plate of 1
00 μm or more.

Furthermore, the resin-coated paper 100 constructed according to the present invention can be manufactured using the first coated roll 2 in the manufacturing apparatus shown in FIG.
01 can be manufactured by forming it into a stepped roll as shown in FIG.

The stepped roll 201 includes a large diameter roll part 201a and a small diameter roll part 201b, and the large diameter roll part 201a has a width (w) of 2 to 3 mm, and a pitch (I2) of each large diameter roll part 201a. 2.3 to 4 mm, and the step difference (h) between the large diameter roll portion 201a and the small diameter roll portion 201b.
) can be 1100u or more. That is, the stepped roll 201 is formed so that the vertical cross section of its peripheral portion is complementary to the desired striped matrix resin coating shape of the resin-coated paper.

In this embodiment, the first coating roller 201 and the second coating roller 202 are connected to the large diameter roll portion 20 of the first coating roller 201.
The outer periphery of the second coating roller 202 is arranged close to the outer circumference of the second coating roller 202, and the first coating roller 201
The ratio of the feed speed VP of the transport roll 203, that is, the release paper 101 to the speed ■1 of the large diameter roll portion 201a (■1/
vp) is the same as before, VP/vp = Q, 9 to 1.2
is set to

According to this embodiment, the matrix resin 10 in the storage tank 204
2 is conveyed in stripes to the release paper 101 side by the first coating roll 201, transferred onto the release paper, and is therefore coated on the surface of the release paper in stripes.

In the above description, the 10th roll 201 was explained as being formed as a stepped roll, but as shown by the dashed line in FIG. It can also be formed into stepped rolls,
Furthermore, both the first and second coating rolls 201 and 202 can be stepped rolls.

Even if the resin-coated paper manufactured by the manufacturing method described in connection with FIGS. 4 to 6 is used, for example, by the prepreg manufacturing method shown in FIG. A striped prepreg can be suitably produced.

Furthermore, in each of the above embodiments, the reinforcing fibers of the prepreg 100 are carbon fibers, and the matrix resin is an epoxy resin. However, the reinforcing fibers and matrix resin of the prepreg according to the present invention may be any material For example, as reinforcing fibers, glass fibers, aramid fibers, and various other fibers can be used, and as matrix resins, phenol resins, unsaturated polyester resins, urethane acrylate resins, vinyl ester resins,
Thermosetting resins such as polyurethane resins can be suitably used. Further, it is preferable that a curing agent and other imparting agents such as a flexibility imparting agent are appropriately added so that the curing temperature is 50 to 200°C.

As described above, in the striped prepreg according to the present invention, a large number of stripes are formed along the axial direction of the reinforcing fibers, so the generation of voids is prevented when the prepregs are laminated, and the physical properties are improved. It has the advantage of being able to provide a laminated prepreg with no deterioration and an excellent appearance.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a resin-coated paper constructed according to the present invention. FIG. 2 is a configuration diagram of a manufacturing apparatus for explaining one embodiment of a method for manufacturing resin-coated paper. FIG. 3 is a configuration diagram of a manufacturing apparatus for explaining a manufacturing method for carrying out the present invention. FIG. 4 is a configuration diagram of a manufacturing apparatus for explaining another embodiment of the method for manufacturing resin-coated paper. FIG. 5 is a front view of the stripe forming member. FIG. 6 is a front view of another embodiment of the coating roll. FIG. 7 is a cross-sectional view of a conventional prepreg. FIG. 8 is a perspective view showing a state in which conventional prepregs are laminated. FIG. 9 is a cross-sectional view of a striped prepreg manufactured according to the present invention. FIG. 10 is a perspective view showing the surface of a striped prepreg manufactured according to the present invention. l O: Subagent prepreg. Release paper: matrix resin, cover film, coating roll conveyor roll stripe forming material

Claims (1)

[Claims] 1) Reinforcing fibers are supplied between the first and second resin-coated papers, or between the first or second resin-coated paper and a mere release paper, and hot pressing is carried out. In the method for producing a prepreg, which is produced by impregnating the reinforcing fibers with a resin, then peeling off one of the release papers, and then releasably attaching a cover film, the first resin-coated paper and/or the second resin-coated paper The resin-coated paper is a prepreg manufacturing method characterized in that the surface of the release paper is coated with a matrix resin in stripes along the longitudinal direction of the release paper. 2) The resin-coated paper coated with the matrix resin in stripes is rotated at a speed of V_1 by a coating roll, so that V_1/V_P≦
2. The prepreg manufacturing method according to claim 1, wherein the prepreg is manufactured by coating a matrix resin of a predetermined viscosity in stripes on release papers that are conveyed in opposite directions at a speed V_P satisfying 0.8. 3) The resin-coated paper coated with the matrix resin in stripes is applied to the coating roll by a coating roll rotating at a speed of V_1, so that V_1/V_P=
A matrix resin of a predetermined viscosity is uniformly coated on release paper that is conveyed oppositely at a speed V_P that satisfies 0.9 to 1.2, and then the coating film is formed into stripes using a comb-like stripe forming member. 2. The prepreg manufacturing method according to claim 1, wherein the prepreg is manufactured by molding. 4) The resin-coated paper coated with matrix resin in stripes is coated with a stepped coating roll that rotates at a speed of V_1, and is applied to the coating roll at a rate of V_1/V.
2. The release paper according to claim 1, characterized in that it is manufactured by coating a matrix resin of a predetermined viscosity in stripes on release paper that is conveyed in opposite directions at a speed V_P that satisfies _P=0.9 to 1.2. Prepreg manufacturing method.