JPS6028567A - Stentering method of fiber bundle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to the widening or opening of fiber bundles, and relates to a method for uniformly and continuously manufacturing a sheet-like tape of fiber bundles aligned in one direction with less generation of fuzz, etc. related to.

[Background technology]

Currently, Gripreg, which is made by impregnating reinforcing fiber bundle tapes such as carbon fibers, glass fibers, and fully aromatic polyamide fibers with thermosetting resins such as epoxy resins and unsaturated polyester resins, is used for leaf springs and honeycomb structures. industrial materials such as
It is also widely used as a molding material for sports and leisure equipment such as fishing rods and golf shafts.

More recently, aircraft materials and automotive materials.

Many studies have been conducted on the use of molding materials using prepreg as described above as medical materials, and some of them have even been put into practical use.

With the diversification of uses for prepregs, there is a growing demand for thinner prepregs as well as improvements in the consistency of reinforcing fibers and uniformity of basis weight distribution. The usual method for manufacturing prepreg consists of widening the fiber bundle as much as possible, forming a sheet tape, and impregnating it with a resin.

Therefore, in order to obtain a thin and homogeneous prepreg, it is very important to open and widen the fiber bundle while minimizing the occurrence of fuzz, damage to #A fibers, etc.

If it were possible to obtain a thin and homogeneous prepreg, it would be possible not only to obtain a thin-walled molded body (but also to enable designs that take advantage of the anisotropic characteristics of unidirectionally aligned fiber-reinforced resins, and to use composite phases. It becomes possible to further expand the applications.

[Purpose of the invention]

The present inventors have arrived at the present invention as a result of various studies on methods for efficiently opening and widening 9pi fiber bundles continuously and with fewer defects such as fuzz.

[Structure of the invention]

The gist of the present invention is to provide a method of spreading the fiber bundle by running the R-thin bundle under tension on the surface of one or more rolls, in which a small number of rolls (one of the rolls) is set to The purpose is to widen the fiber bundle by rotating it slowly.

The present invention will be specifically explained below.

Table 1 shows the results of an experiment conducted using the fiber bundle widening experiment apparatus shown in FIG. 1 in order to investigate the relationship between the rotation and fixation of the rolls and the widening of the fiber bundle.

In FIG. 1, (1) is a fiber bundle, (2) is a fiber bundle bobbin unwinding device with a band brake, (3) is a guide,
(4), (5), and (6) are freely rotatable and fixable rolls for widening the fiber bundle, and (7) is a fiber bundle widening device.

The fiber bundle used is 3000 fiI made of carbon fiber! ,
200 Tn9/m, running conditions are 1
m/min, and the tension is 500 J'.

Table 1 As is clear from Table 1, fixed rolls are preferable to widen the fiber bundle, and in the above experiment, the spread width was 1.5 mm between the three widening rolls fixed and free rotation. 5
More than twice as different. However, those using fixed rolls have a problem in that they are impractical due to the occurrence of fluff and fluff build-up on the rolls, which indicates that improvements are needed.

Figure 2 shows a fiber bundle widening experimental device in which the widening roll of the device shown in Figure 3 is equipped with a variable speed motor and a drive device (8) released from a gear box. The results of a fiber bundle widening experiment are shown. The fiber bundle used was 3000f16.200m9/m made of carbon fiber.
It's something.

The running conditions are 1 m/rnfn and the tension is 500.
It is 1.

Table 2 From the experimental results shown in Table 2, it is clear that by rotating the widening roll either freely or at a slow speed relative to the traveling speed of the fiber bundle, it is possible to suppress the generation of fuzz on the roll and the accumulation of fuzz. It is clear that the width can be expanded efficiently.

Cases 1 and 2 in Table 2 are #1! This shows the case where the fiber bundle is rotated at a surface speed higher than or the same as the traveling speed of the fiber bundle, and although there is no damage to the fiber bundle, the widening effect is extremely small.

In Cases 3 and 4, there was no damage to the fiber bundles, and a considerable widening effect was observed.

In case 5, although some fluff was observed, there was no fluff accumulation, so stable running could be continued.

In Case 6, when the roll is fixed, in addition to the occurrence of 2 fuzz, the 9 fuzz buildup is severe and if the roll is run for a long time, cracks will occur in the widened fiber bundle at the part where the 2 fuzz is accumulated, and the accumulated fuzz will become clumps. Stable running was not possible due to entanglement with fiber bundles.

From the experimental results shown in Table 2, it is clear that whether the widening roll is free-rotating or fixed (by selecting the rotational speed so that the surface speed of the roll is slower than the running speed of the fiber bundle running under tension), It is clear that the width of the bundle can be efficiently expanded.

An example of manufacturing a prepreg using the method of the present invention will be explained with reference to FIG.

The aligned fiber bundle (11) is passed through the feed roll (1
2), passes through a guide comb (13), is widened on a widening roll (14) equipped with a drive device (20) consisting of a variable speed motor and a gear box, and is combined with a release paper (15) coated with resin. and preheating plate heater (16)
After being heated with and laminating the release paper (18) for roll protection,
Impregnated with resin by a heated nip roll (17) for resin impregnation,
It is wound up on a prepreg winding roll (19).

For example, when the method of the present invention is applied to carbon fibers, fiber bundles composed of conventionally commonly used carbon fibers with a fiber diameter of 8μ or more (2 to 3 ultrafine carbon fibers of about 2 to 3μ) It is possible to obtain excellent performance even when applied to a fiber bundle consisting of 10,000 fibers.

The present invention will be explained below with reference to Examples.

Example Table 3 shows that 3,000 f
Carbon fiber bundle (unit length weight approx. 20 omy/m) 1
500 manufactured from 25 pieces and release paper coated with resin
The performance of mm-width prepreg was shown.

The prepreg manufacturing conditions were a running speed of 2 m/min.

Surface speed of fiber bundle widening roll 0.2 m/min,
The prepreg full width tension was 120 kP, the preheating plate heater temperature was 130°C, and the heating roll temperature was 100°C.

Table 3 As is clear from Table 3, it can be seen that the method of the present invention provides a high quality, ultra-thin, unidirectional fiber reinforced prepreg.

Ratio J plate side 1 / Other than that, the fiber bundle widening roll was made to rotate freely.

The performance of the prepreg manufactured in the same manner as in Example 1 was evaluated in the fourth example.
Shown in the table.

Table 4 As is clear from Table 4, when the widening roll was rotated freely, no fuzz was observed in the prepreg, but the fiber bundles were insufficiently widened, resulting in a large number of openings. It was unusable.

Comparative Example 2 Table 5 shows the performance of a prepreg produced in the same manner as in the example except that the fiber bundle widening roll was fixed.

Table 5 As is clear from Table 5, when the widening roll is fixed, the fluff due to the accumulation of two fluffs can be seen in clusters on the prepreg. I couldn't get it.

〔Effect of the invention〕

Since the method of the present invention can continuously produce a homogeneous thin plate-like tape from a unidirectionally aligned fiber bundle,
When applied to the production of prepreg, it is possible to continuously and stably produce homogeneous and thin prepregs that are free from appearance defects such as fuzz over a long period of time.

[Brief explanation of the drawing]

Fig. 1 shows a fiber bundle widening device having a roll for widening the fiber bundle which can be freely rotated or fixed, and Fig. 2 shows a fiber bundle widening device suitable for carrying out the present invention, in which a widening roll driving device is further attached to the device of Fig. 1. Bundle Expanding Apparatus, FIG. 3 shows an example of an apparatus for producing unidirectionally aligned fiber-reinforced griplegs incorporating a fiber bundle widening apparatus. (1), (11) Fiber bundle (4), (5), (6), (14) Widening roll (
15) Release paper coated with resin (18) Release paper for roll protection

Claims (1)

[Claims] A method of pushing and spreading a fiber bundle by running the fiber bundle while pressing it under tension against the surface of one or more rolls, in which the running of the fiber bundle on one or more rolls is performed. A fiber bundle widening method characterized by rotating at a slow speed.