JPH02216284A - Electrically conductive composite fiber and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject fiber suitable as piles of carpets by mixing electrically conductive short fiber, such as carbon fiber, with a synthetic resin, spinning the resultant mixture, then dissolving only the synthetic resin on the surface of the spun fiber with a solvent and projecting the electrically conductive short fiber over the fiber surface. CONSTITUTION:The objective fiber obtained by mixing electrically conductive short fiber, such as carbon fiber, with a synthetic resin, spinning the resultant mixture, then dissolving only the synthetic resin present on the surface of the spun fiber with a solvent and projecting the above-mentioned electrically conductive short fiber over the surface.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a conductive composite* fiber and its S3 application method, and more specifically, conductive angular fibers protrude from the surface of the fiber made of synthetic resin, resulting in conductive performance ζ This article relates to an excellent conductive composite [11] and a method for producing the same.

(Conventional technology) When carpets, clothing, etc. generate static electricity due to friction between fibers and become charged, they attract dirt and dust, making them more dirty, causing damage to surrounding electronic equipment, and causing harm to people. There were negative effects such as giving unpleasant electric shocks. For this reason, many conductive fibers used for static protection +h have been proposed.

The conductive fibers are made by mixing and uniformly dispersing a thermoplastic resin (5I) and a conductive component (52) such as carbon fiber or carbon black, as in the fiber (50) shown in Figure 5. However, the cross section of the fiber is spun into a polygonal shape such as a star, as shown in the fiber (60) shown in Figure 6, which is proposed in Special Publication No. 62-170508. There are those in which a thermoplastic polymer (61) containing a sex substance is arranged, and those with a core-sheath structure proposed in Japanese Patent Publication No. 31450/1982 and Japanese Patent Application Laid-open No. 90316/1983.

(Problem 8 to be solved by the invention) However, as shown in FIG. There is a problem in that it is expensive because it requires a spinning device.

In addition, conductive fibers with a core-sheath structure and thermoplastic phase as shown in Figure 5! In the conductive fiber (50) in which the conductive component (52) is uniformly dispersed in the conductive fiber (51), the conductive component (52) is only slightly exposed on the m-line surface, resulting in poor conductive performance. There is. This conductive performance can be improved by increasing the mixing ratio of the conductive component (52), but increasing the mixing ratio of the conductive component (52) poses a problem in that physical properties such as strength deteriorate.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a conductive composite fiber that has excellent physical properties such as strength, excellent conductivity, and is easy to manufacture and inexpensive, and a method for manufacturing the same.

(Means for Solving the Problems) In order to achieve the above object, in the conductive composite fiber according to claim 1, the surface of the fiber made of a synthetic resin mixed with conductive short fibers such as carbon fibers is It is characterized by the fact that conductive short fibers are provided so as to protrude.

In addition, in the method for producing conductive composite fibers according to claim 2, after mixing conductive short fibers such as carbon fibers with synthetic resin and spinning them, only the synthetic resin on the surface of the spun fibers is treated with a solvent. It is characterized in that the fibers of the conductive layer are made to protrude from the surface of the fibers by melting the fibers.

(Function) According to the structure according to claim 1, the fibers made of synthetic resin mixed with conductive short fibers such as carbon fibers do not have scratches on the surface, so physical properties such as strength etc. It has excellent properties and can be used as a pile for carpets, etc., and also has excellent electrical conductivity and discharge performance due to the conductive short fibers protruding from the surface of the fibers.

Furthermore, in the structure according to claim 2, after mixing conductive short fibers such as carbon fibers with synthetic resin and spinning them,
When only the synthetic resin on the surface of the spun fibers is dissolved with a solvent, the conductive short fibers protrude from the surface of the fibers, so they are made of synthetic resin! ! A conductive composite fiber in which the conductive short fibers protrude from the male surface can be easily obtained.

(Example) Hereinafter, an example of a conductive composite fiber embodying the present invention and a method for manufacturing the same will be described with reference to the accompanying drawings.

As shown in Fig. 1, this conductive composite fiber (1) is made of a non-conductive synthetic resin (2) and is provided with conductive pair WK fibers (3) such as carbon fibers protruding from the surface of the fiber. It is being

Therefore, this conductive composite! In ll fiber (+), many conductive short fibers (3) are protruding from the fiber surface, so it has excellent overall conductive performance and has good static electricity from each conductive short fiber (3). is discharged.

In addition, as the conductive short fiber (3), in addition to carbon fiber,
The material may be appropriately selected from metal fibers, ceramic fibers, etc. and used.

Next, a method for manufacturing the conductive composite fiber (1) will be explained. To manufacture this conductive conjugate fiber (1), first, a melt-spun non-conductive synthetic resin material such as nylon, polyester, polypropylene, polyethylene, etc. is prepared as the main raw material.

On the other hand, as an auxiliary raw material, a conductive composite fiber (3) with a finer denier than the product is prepared. If the conductive staple fiber (3) is too thick, the manufactured conductive composite fiber This is because the texture, physical properties, etc. of (1) become unstable.

Furthermore, the cut length of the conductive short fibers (3) is determined by taking into consideration the diffusivity when mixed with the main raw material, and also by considering the appropriate texture, physical properties, and conductivity of the conductive composite fiber (1) as a product. Considering performance etc., the thickness is preferably 5 mm or less.

Next, the synthetic resin (2) as the main raw material is thoroughly mixed with conductive short fibers (3) as an auxiliary raw material whose mixing ratio to the main raw material is preferably about 10% or less. The reason for this mixing ratio is to ensure that the next spinning process is stable, and to ensure that the conductive conjugate fiber (+) produced
This is to make the texture, physical properties, etc. of the synthetic resin (2) good, close to the properties of the synthetic resin (2) itself.

Next, the mixture of the main raw material and the auxiliary raw material is used as a raw material for spinning (-next processing).

As this spinning method, the melt spinning method is first known, and in this melt spinning method, a synthetic resin (2) mixed with conductive short fibers (3) is heated and melted and extruded through pores for spinning. , which is cooled and solidified before being stretched. In this melt spinning method, it is desirable that the melting point of the conductive short fibers (3) is 100 degrees Celsius or more higher than the melting point of the main raw material synthetic resin (2).

Note that as another spinning method, an extrusion spinning method is known. In this extrusion spinning method, when thermal decomposition of the synthetic resin (2) starts at the melting point, the synthetic resin (2) mixed with the conductive short fibers (3) is heated to a softening point lower than the melting point of the synthetic resin (2). It is heated, extruded through pores, and spun.

Further, as another spinning method, a wet spinning method is known. This wet spinning method involves dissolving the synthetic resin 2) in a solvent to obtain a spinning solution, extruding this spinning solution through pores into a coagulation bath and coagulating it into filaments, which are then subjected to stretching, heat treatment, drying, etc. It is.

As shown in FIG. 2, the fibers (la) spun by each of the above-mentioned spinning methods have the conductive short fibers (3) exposed on the surface thereof, and the conductive short fibers (3) are similar to the fibers (1a). ) are intertwined and in contact with each other, so the whole has electrical conductivity. In addition, this spun fiber (1a) has a low mixing ratio of conductive short edges &II (3'), so its physical properties such as strength are close to those of the fiber made only of the main raw material synthetic resin (2). Become.

However, this spun fiber &tt(la) has a slightly inferior conductive performance because the exposed portion of the conductive fiber (3) on its surface is small.

Therefore, in order to improve the conductivity of the spun fill (la), the following processing (secondary processing) is performed.

That is, fi&1l(
By dissolving only the synthetic resin (2) on the surface of 1a) with a solvent and making the fibers (1a) slightly thinner, the first
As shown in the figure, the conductive short edges &i (3) are made to protrude from the surface of the conductive composite fiber (1). In this processing method, a solvent is prepared that dissolves the main raw material synthetic resin (2) and does not dissolve the auxiliary raw material conductive short fibers (3), and the spun fibers (la ). Another method is to pass the spun fiber (Ia) through the I# liquid containing the solvent.

Then, the electrically conductive composite fiber (1) produced through secondary processing increases the exposed portion of the electrically conductive short fiber (3) on its surface, so the electrical conductivity is greatly improved. It is also simple and inexpensive to manufacture. Furthermore, in the secondary processing, the spun fiber &tt(l
Since there are no scratches or tears in a), the electrically conductive composite fiber (1) manufactured through secondary processing does not change significantly in physical properties such as strength from before processing. .

Next, an example JJt of an automobile mat with antistatic performance provided using this conductive composite fiber (1) will be described.

As shown in FIG. 3 and FIG. Pile of books (2)
0) is driven into the specified polyurethane,
A binding thread (21) is sewn onto the base fabric (11) and the conductive layer (12) so that the pile (20) that has been driven in does not come off. Further, on the back side of the conductive layer (12), a lining material (13) made of thermoplastic synthetic resin is provided.
) is lined.

The base fabric (11) is a woven fabric, a mesh, or a nylon woven fabric cut into a predetermined shape. The conductive layer (
12) exists in a stacked state of conductive materials such as powdered, granular, or short fiber carbon materials, conductive ceramics, or metals, and is used when getting in and out of a car or while driving. It is designed to absorb static electricity generated by friction between (10) (10) and the hem of shoes or pants.

＠Vile (20) refers to multiple threads bundled at a ratio of about 40 nylon fibers to 1 conductive composite fiber (1), which are twisted together to a specified thickness. ing.

Therefore, in this automobile pine) (10), the conductive composite fiber (1) with excellent conductivity contained in the pile (20) comes into contact with the conductive material of the conductive layer (12>), and (12) The static electricity absorbed by the conductive composite H
Because it is efficiently discharged in the air through the conductive short fibers (3) protruding from the surface of the fibers (1), static electricity [thus attracts dirt and dust, can cause dirt to become concentrated, and can cause damage to surrounding electronic equipment]. It is possible to prevent harmful effects such as giving unpleasant electric shocks to people.

Furthermore, this conductive composite 1a fiber (I) has excellent physical properties such as strength, so it can be used as a pile (20) that forms the surface of automobile mats (10), etc., which are laid under people's feet and are constantly trampled on. It does not break even when used for automobiles, and the antistatic effect of (10) can be maintained for a long period of time.

It should be noted that the present invention is not limited to the above embodiments, but 1
The spinning method of the ia fiber (1a), the raw material of the conductive conjugate fiber, etc. may be changed as appropriate and carried out without departing from the spirit of the present invention.

(Effects of the Invention) As detailed above, the conductive composite fiber according to the present invention has excellent conductive performance due to the conductive short fibers protruding from the back surface, and also has static electricity from the conductive short fibers. It has the excellent effect of efficiently discharging electricity and providing textile products with excellent antistatic performance.

Furthermore, the method for producing conductive composite fibers according to the present invention has the excellent effect of being able to easily and inexpensively provide conductive composite W and fibers in which conductive short fibers protrude from the fiber surface.

[Brief explanation of the drawing]

Fig. 1 is an enlarged perspective view showing an example of a conductive composite fiber embodying the present invention, and Fig. 2 is an enlarged perspective view of a fiber spun by mixing conductive short fibers such as carbon fibers with synthetic resin. ,
Fig. 3 is a perspective view of an automobile mat using the conductive composite fiber of the present invention, Fig. 4 is an enlarged cross-sectional view of the main part of automobile pine I, and Fig. 5 is an enlarged cross-section of a conventional conductive fiber. 6 are enlarged sectional views of other conventional conductive fibers. Explanation of symbols 1... Conductive composite fiber, 1a... Spun fiber, 2... Synthetic resin, 3... Conductive short fiber, IO... Car mat, 20...・
pile. Patent applicant Daiwa Co., Ltd. Figure 4 Figure 4

Claims (2)

[Claims] (1) A conductive composite fiber characterized in that the conductive short fibers are provided so as to protrude from the surface of a fiber made of a synthetic resin mixed with conductive short fibers such as carbon fibers. (2) After mixing conductive short fibers such as carbon fibers with synthetic resin and spinning them, only the synthetic resin on the surface of the spun fibers is dissolved with a solvent, and the conductive short fibers are made to protrude from the surface of the fibers. 1. A method for producing a conductive composite fiber, characterized in that: