JPS5922859A - Carbon-filament package - Google Patents

Abstract

PURPOSE:To obtain a package which has the improved filament releasing property because of possibility of neither shape deformation nor slip-off of single layer from a bobbin by winding-up a carbon filament in a specific apparent winding-up density onto a bobbin which has an outside diameter of a specific length or above and on which uneveness is formed. CONSTITUTION:The outside diameter of a bobbin 1 is set at 50mm. or more, so generation of fluff due to breakage of monofilament is prevented, obviating the bending in any severe curvature. Uneveness 2 for preventing slip-off of single layer by increasing the frictional force with carbon filament is formed on the surface of the bobbin 1. Onto the surface of said bobbin 1, a carbon filament 3 is wound-up in apparent winding-up density of 0.75-1.1g/cm<2>. Said apparent winding-up density means the value obtained by dividing the weight W(g) of the wound-up filament by the apparent volume of the filament. Therefore, the amount X of filament wound-up per surface area (cm<2>) of the bobbin 1 can be increased to about 3-8g., and a package which has an improved filament releasing property because of possibility of neither shape deformation nor slip-off of single layer from the bobbin 1 can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a carbon fiber pancage capable of being rolled in large quantities.

Conventionally, it has been known to preheat fibers made of organic polymers such as polyacrylonitrile fibers, cellulose fibers, and pitch fibers, and then carbonize them in an inert atmosphere in a high-temperature heating furnace to obtain carbon fibers that are excellent as reinforcing materials. It is being

On the other hand, in the winding process in the carbon fiber manufacturing process, efforts are being made to use cheese-wrapping (software end winding) and large-volume winding in order to reduce the amount of winding work, shipping costs, and transportation costs. is being paid.

However, carbon fiber has an extremely high Young's modulus and poor elasticity, so the tension range in which it can be wound is extremely small.
If the tension is too low, the winding end surface will collapse, deformation due to external force,
Troubles such as the thread-wound layer slipping through from the bobbin are likely to occur.On the other hand, if the tension is too high, problems such as damage to the thread during winding and deterioration of unwinding properties may occur. It was technically difficult.

The object of the present invention is to solve the above-mentioned drawbacks, and to provide a package that prevents the winding layer from slipping from the bobbin, does not lose its shape, and has good unwinding properties in a large quantity of cheese-wound carbon fiber banks. We aim to provide the following.

The structure of the present invention that achieves the above object is a carbon fiber wound with an apparent winding density of 0.75 to 1.17/cnl around a bobbin having an uneven surface and an outer diameter of at least 50 mm. It is intended to be a fiber package.

FIG. 1 is a perspective view of a paper tube bobbin applied to the present invention. Since carbon fibers are weak against bending and easily break, in the present invention, the outer diameter of the bobbin 1 is set to 50 ynrn or more to avoid bending with a high curvature and prevent the generation of fuzz due to breakage of single yarns.

The surface of the bobbin is also textured (embossed) 2 to increase the frictional force with the carbon fiber and prevent the winding layer from slipping through. The embossing process (can be done by pressing the bow 2 bobbin surface material with a female mold having a desired pattern, such as a wire mesh, has 8-50 concave or convex parts/
It is preferable that the carbon fibers 1 are regularly arranged and formed with a density of Cll1. In the present invention, the carbon fibers 1 are formed on such a surface-treated bobbin with an apparent winding density of 0575 to 1,11-/c2.
It is wound on rt. The apparent winding density here means the weight of the wound yarn W (, yl
is divided by the apparent volume occupied by the yarn, and in FIG. 2, 6 is carbon fiber. Here, the outer diameter of the winding layer is D(to)), the inner diameter is dhi++j, and the winding width is Lf:r→
Then, it is shown by.

By winding carbon fiber at such an apparent winding density, the present invention can achieve a yarn ft (ft) wound per 1 ca of bobbin surface area.
X) (see Figure 3) can be wound in large quantities of about 3 to 8 threads, and can be made into a package with good unwinding properties without losing its shape or slipping through the winding layer from the bobbin. .

Example number of filaments: 6000, grain size (weight of yarn i 172): 0.459-/ynl Epicor 1-834
Carbon fibers coated with approximately 0.7 weight of epoxy polymer (manufactured by Shell) are wound around paper tubes with an outer diameter of 58 and a textured surface. Packages with different winding densities are created by varying the tension. I wound it up. For these wound packages, the yarn was pulled out in the axial direction of the bobbin at a speed of 20 m/min, and the unwinding tension was measured.

Measurements were carried out in a room with a temperature of 25°C and a relative humidity of 65% after adjusting the humidity. After drawing the turns on a chart, the average value and the tension per yarn length of 20 ++ Z (measured at 111 hours and 1 minute) were measured. The number of abnormalities (the number of swings showing 2 times or more of the average value) was determined.

In addition, to determine the degree of slippage between the bobbin and the thread-wound layer, a pancage with different winding amounts was tested by dropping it from a height of 2' Oon onto a concrete floor in the direction of the bobbin axis. The maximum winding amount that would cause a relative deviation of 5 mm or more was determined.

Note that the packages used in these tests were those that had been ingested for more than 4.5 months after being rolled up.

The test results are shown in Table 1. O As is clear from Table 1 below, the apparent winding density is 0.75 y.
If it is smaller than -/cut, the upper limit winding amount (d:2)/cut will not cause any shift in the winding layer, and if it is less than that, it is impossible to wind a large amount.

If the apparent winding density is 1.1 or more, the upper limit winding amount can be increased, but the unwinding tension of the yarn increases and the number of tension abnormalities increases rapidly.

By setting the apparent winding tightness within the range of the present invention, it is possible to obtain an excellent package with good unwinding properties and short, large volume winding with no misalignment between the winding layer and the bobbin.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a bobbin applied to the present invention. Second
The figure is a perspective view for explaining the apparent winding density. FIG. 6 is a perspective view for explaining the amount of winding per unit surface area of the bobbin. 1...Bobbin 2...Irregularized surface 6...Carbon fiber 349

Claims (1)

[Claims] The bobbin has an uneven surface and an outer diameter of at least 50 mm, and the carbon fiber has an apparent winding density of 0.75 to 1.1.
A carbon fiber package characterized by being wrapped in f/atl.