JPS61194220A - Production of conductive conjugated fiber - Google Patents

Abstract

PURPOSE:Immediately after extrusion, the conductive conjugated yarn is cooled down lower than glass transition point, then the yarn flow bended with a specific method and taken up with a godet roller, and wound up at a higher speed to enable low-cost production of the titled yarn of high conductivity with good operability. CONSTITUTION:A thermoplastic polymer containing fine conductive particles and another fiber-forming thermoplastic polymer are extruded, e.g., from spinner et 1 in an extruder and the melt-extruded conjugated yarn 2 is cooled with air from the cooling-air blower 3 down below the glass transition point. Then, the resultant yarn is brought into contact with a stationary friction body 6 and bended by an angle of 15-60 deg., then taken up with a godet roller 7 and wound up into a package 8 more than 3,500m/min. The stationary friction body 6 is preferably a ceramic pin.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing conductive composite yarn by high-speed melt spinning.

(Prior art) Conductive composite yarns made of thermoplastic polymers containing conductive fine particles and fiber-forming thermoplastic polymers are well known, and by mixing a small amount with electrostatically charged fibers, they can be used to prevent static electricity in textile products. Widely used for sexual purposes.

When manufacturing such conductive composite yarn, after melt spinning,
There is a problem that the conductivity decreases significantly when stretched.
A method of obtaining yarn with excellent conductivity by melt spinning at high speed and omitting drawing was disclosed in Japanese Patent Application Laid-Open No. 49-499.
This method has been proposed in Publication No. 19, Publication No. 5B-132121, and the like.

Generally, when performing melt spinning at high speed, a device as shown in FIG. 3 is used, and the composite yarn 2 spun from the spinneret 1 is
After being cooled by the cooling air from the cooling air blower 3 and passing through the duct 4.

A lubricant is applied by the lubricating device 5, and the godet roller 7a
, 7b, and is wound up as a package 8 by a high-speed wine gourd.

(Problems to be Solved by the Invention) When employing such a high-speed melt spinning method, a yarn with the desired strength and elongation cannot be obtained unless the spinning speed is extremely high.
There are problems in operation, and since two godet rollers are used, there is a problem in that the operating cost is high.

An object of the present invention is to provide a method for producing a composite yarn with excellent conductivity at low cost and with good operability.

(Means for Solving the Problems) The present invention achieves the above objects, and the gist thereof is as follows.

When producing a composite yarn consisting of a thermoplastic polymer [A] containing conductive fine particles and a fiber-forming thermoplastic polymer (B) by a melt spinning method, the spun yarn is cooled to a temperature below the glass transition point. After that, the conductive composite yarn is brought into contact with a non-rotating friction body, bent at a bending angle of 15 to 60 degrees, taken up by one godet roller, and wound at a speed of 3500 m/min or more. .

In the present invention, as the conductive fine particles, conductive carbon blacks such as acetylene black, channel black, furnace black, thermal black, lamp black, cupric iodide particles, and tin oxide particles are preferably used.

The cupric iodide particles and the stannic oxide particles include individual particles of cupric iodide and tin oxide.

It contains particles coated with inorganic substances such as titanium oxide, zinc oxide, calcium oxide, magnesium oxide, calcium carbonate, and alumina. In the case of stannic oxide-based particles, it is preferable that the conductivity is enhanced by a small amount of an antimony compound.

These particles preferably have a resistivity of 10'Ω·cll+ or less, preferably 10"Ω·C- or less, and from the viewpoint of operability, particles with a diameter of 5μ or less, preferably 3μ or less. When using conductive carbon black particles, the blackness of the carbon black itself becomes a problem, so when obtaining threads for use in applications that require white bark, cupric iodide particles or sulfuric oxide particles are used. It is preferable to use tin-based particles.

Moreover, as thermoplastic polymers [A] and [B].

Polyethylene terephthalate, polybutylene terephthalate, poly-1,4-cyclohexylene dimethylene terephthalate, polyethylene-2,6-naphthalate, poly-p-ethyleneoxybenzoate, etc., and polyesters containing these as main components.

Nylon 6, nylon 11. Nylon 12. nylon 6
6. Typical polymers include nylon 610, polyamides containing these as main components, polyethylene, polypropylene, etc., and polyolefins containing these as main components.
B] For the acid component, a polymer with good fiber-forming properties is selected; however, for the acid component [A], a polymer with poor fiber-forming properties may be used for the purpose of improving the dispersibility of the conductive fine particles. do not have.

In the present invention, the conductive fine particles are blended as uniformly as possible into the acid component thermoplastic polymer [A] using, for example, melt blending, and the blending amount is adjusted to the required conductive performance, silk-spinning properties, 9 colors, 1 Jl (white skin), etc. ) etc., but it can be decided by taking into account
It is preferably 20 to 80% by weight of component [A], and the weight ratio of component [A] and component (B) forming the composite yarn is preferably 5:95 to 50:50.

Figure 2 (a) to (c) are composite yarns (single yarn) in the present invention
This diagram schematically shows a typical example of the cross-sectional shape of
The shaded area is the [A] component.

The shaded area represents the (B) component.

Next, the method of the present invention will be explained with reference to FIG.

Component [A] and component (B) are supplied to the spinneret 1 by separate extruder-type extrusion devices, and are spun as a composite yarn 2. The spun composite yarn 2 is cooled by cooling air near room temperature from the cooling air blowing device 3, passes through a duct 4, is applied with an oil agent by a slit-type oil supply device 5, and comes into contact with a non-rotating friction body 6. , bending angle (θ) 15-60
It was bent at @ and picked up by one Godet Rough.

The package 8 is wound up at a high speed of 3500 m/min or more.

The method of the present invention is not limited to the method using the apparatus shown in FIG. 1;9 For example, it is also possible to supply oil before or before and after the duct 4, or to provide entanglement at an appropriate position.

As the non-rotating friction body 6, a pin made of ceramic, titanium oxide, alumina, etc. is preferable. The cross-sectional shape and surface roughness of the friction body depend on the type and cross-sectional shape of the composite yarn.

It is changed as appropriate depending on the spinning speed, etc.

The composite yarn brought into contact with the non-rotating friction body 6 must be cooled to a temperature below the glass transition point, and the object of the present invention will not be achieved if the composite yarn is brought into contact with the friction body before being sufficiently cooled. In addition, it is necessary to make the bending angle (θ) between 15 and 60 degrees. If it is less than 15", the thread tension before contacting the friction body will be too large, making it impossible to wind at high speed and reducing the conductivity. On the other hand, if it exceeds 60'', the yarn tension becomes too small and the operability of high-speed winding deteriorates.

(Function) When high-speed spinning is performed using the conventional method shown in Figure 3, the high-speed running yarn that has been cooled and solidified is directly picked up by a rotating godet roller with a large yarn gripping force, so that the spinning stress is concentrated at one point. As a result, in the case of a composite yarn consisting of the [A] component with poor spinnability and the [B] component with good spinnability, the deformation of one stroke component is not performed smoothly, and thread breakage occurs frequently.

On the other hand, according to the method of the present invention, the high-speed traveling yarn contacts the non-rotating friction body, is bent, and is taken off by the godet roller, so that the spinning stress is not concentrated at one point. That is, the spinning stress is dispersed before and after the non-rotating friction body with a small yarn gripping force.

It is recognized that the image components are transformed smoothly.

(Example) The present invention will be explained in more detail below with reference to Examples.

The electrical resistance value of the yarn in the examples is the resistance value measured when yarns of 10 ctm length are randomly sampled 30 times from a sample of 1000 tm length and a DC voltage of IKV is applied to each sample. This is the one that showed the highest value.

Examples and Comparative Examples 50 parts by weight of stannic oxide particles with a particle diameter of 0.2μ and a specific resistance of 1Ω/cII+ were melted and uniformly dispersed in 50 parts by weight of nylon 6. Chips [A] and titanium oxide were mixed by 1 weight. % containing normal nylon 6 chips [B] at a weight ratio of 15:8.
With the apparatus shown in Figs. 1 and 3, 270
Composite spinning is carried out at ℃ and has a single yarn cross section as shown in Fig.
A yarn of d/4f was obtained.

At this time, the non-rotating friction body 6 has a diameter of 10 mm.

Alumina pins with a surface roughness of 6S were used, and the roller speed and bending angle were as shown in Table 1.

Tension To at a point 5 cm above the bottle 6 or roller 7a,
Table 1 shows the tension Tl + stringiness at a point 5 cm + upstream from roller 7 or roller 7b, the elongation of the obtained yarn, and the electrical resistance value.

The evaluation of stringability is as follows: ○: Good, Δ: Lots of fuzz, ×:
It was carried out in three stages with no spinnability.

As is clear from Table 1, among cases 5 and 6 using the spinning apparatus shown in Fig. 3, case 5 had too much spinning tension applied to To.
It has the disadvantages of poor spinnability and high elongation. On the other hand, in the case of the magnet 6, too much spinning tension is applied to T, resulting in poor operability, and the conductivity is also reduced because it is stretched between rollers.

Using the device shown in Figure 1! Among lhl~4, Arashi 1, which has a too small bending angle, has uneven tension in T1 and has poor stringability.
On the other hand, in the case of the thread 2 having a large bending angle, the tension is biased towards To, resulting in poor threadability. In case 3.4, which is an example of the present invention, the tension is T
A conductive composite yarn was obtained which was dispersed in T+, had good operability, and had satisfactory filament properties and electrical resistance.

(Effect of the invention) According to the present invention, 3500
A yarn with desired physical properties can be obtained at a spinning speed of about 5,000 m/min, and a composite yarn with excellent conductivity can be produced with good operability. Also, the godet roller is 1
Since only one unit is required, operating costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an apparatus for carrying out the method of the invention;
Figure 2 (a) to (c) are composite yarns (single yarn) in the present invention
FIG. 3 is a schematic diagram of a conventional device. 2-Composite yarn, 6-Non-rotating friction body, 7-Godet roller.

Claims (3)

[Claims] (1) When producing a composite yarn consisting of a thermoplastic polymer [A] containing conductive fine particles and a fiber-forming thermoplastic polymer [B] by a melt spinning method, the spun yarn is heated to a temperature below the glass transition point. After cooling to temperature, contact with a non-rotating friction body,
A method for producing a conductive composite yarn, which comprises bending the yarn at a bending angle of 15 to 60 degrees, taking it off with one godet roller, and winding it at a speed of 3500 m/min or more. (2) The method according to claim 1, wherein the conductive fine particles are conductive carbon black particles, cuprous iodide particles, or tin oxide particles. (3) The method according to claim 1, wherein the polymers [A] and [B] are polyester, polyamide, or polyolefin.