JPH02200827A - Electroconductive combined filament yarn and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject combined filament yarn having excellent electroconductivity, yarn properties, hue and dyeability by combining a core- sheath type electroconductive conjugate fiber comprising of sheath part of thermoplastic polymer and core part containing low-melting point metal specified its mixing ratio and shape in length direction and a non-electroconductive fiber. CONSTITUTION:A non-electroconductive fiber is combined with a core-sheath type electroconductive conjugate fiber using metal having melting point lower than the thermoplastic polymer in sheath part as core part in which sectional ratio of the core in cross section of the fiber is 0.2-50% and degree of variability of cross-sectional area of core part in length direction in <=25%, and the core part is substantially continued in length direction. Shrinkage in boiling water of the two fiber are respectively adjusted as <=15%, difference of the shrinkage in boiling water is adjusted as 0-15% and mixed ratio of the core-sheath type electroconductive conjugate fiber is adjusted as 0.25-46wt.%.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a conductive mixed fiber yarn containing a core-sheath type conductive conjugate fiber and having excellent conductivity and excellent yarn physical properties, hue, and dyeability. .

(Prior Art) Synthetic fibers, such as polyester fibers and polyamide fibers, have low conductivity, so Wl! Static electricity is easily generated due to rubbing, and when using fabrics made of such synthetic fibers, various problems occur due to dust adhesion and discharge. In order to solve this problem, it is known to mix conductive fibers into textile products, and examples of conductive fibers include metal fibers, metal-plated fibers, fibers blended with carbon black and/or conductive substances, etc. It has been proposed (Japanese Patent Publication No. 11909/1982, Japanese Patent Publication No. 44579/1982, Japanese Patent Publication No. 37322/1982, Japanese Patent Application Publication No. 57/1989)
93520).

Furthermore, a conductive mixed fiber yarn consisting of a conductive composite fiber containing conductive metal oxide particles and a non-conductive fiber has also been proposed (Japanese Patent Publication No. 56334/1982).

(Problem H to be solved by the invention) By the way, the above-mentioned Japanese Unexamined Patent Application Publication No. 11909/1987 relates to conductive core-sheath type composite fibers containing a low melting point metal as a core component. However, according to the example and Figure 1, the metal is spun as a core component under its own weight, and therefore the rate of variation in the area of the core component is considered to be quite high, and moreover, the core component is continuous for 5 cm or more along the fiber axis. There are quite a few problems in terms of conductivity, since it is fine if the

Furthermore, since the material described in Japanese Patent Publication No. 53-44579 has electrically conductive carbon black dispersed substantially uniformly throughout, it has various problems in terms of yarn properties, hue, dyeability, etc. and was not satisfactory.

Furthermore, the fiber described in Japanese Patent Publication No. 56-37322 is a conductive conjugate fiber containing a carbon blank, which has similar problems in terms of yarn properties, hue, dyeability, etc.

Furthermore, the material described in JP-A-57-193520 also includes a material whose core component is a thermoplastic polymer blended with stannic oxide fine powder containing an antimony compound. , while the white skin becomes high, problems arise in terms of stainability.

Furthermore, the method described in Japanese Patent Publication No. 61-56334 is a low-oriented film formed by bonding a protective layer made of a fiber-forming polymer and a conductive layer made of a binder polymer containing conductive metal oxide particles. This paper relates to a conductive mixed yarn consisting of a highly oriented conductive composite fiber and a highly oriented non-conductive fiber, but this mixed yarn has improved whiteness compared to a conductive yarn using carbon black. However, because metal oxide particles are used as the conductive layer of the conductive composite fiber, there is a problem in terms of dyeability that the difference in dyeing between the base fabric of the dyed fabric and the conductive yarn becomes noticeable, so it is not suitable for general clothing. It wasn't versatile. That is, even if metal oxide particles are included in the core, there is a problem in that the side surfaces of the conductive thread are affected by the metal oxide particles in the core and are greatly affected by dyeability.

Therefore, the present invention solves the drawbacks of the conventional technology and provides a conductive mixed fiber consisting of a core-sheath type conductive composite fiber whose sheath part is made of a thermoplastic polymer and whose core part is made of a low melting point metal, and a non-conductive fiber. It provides thread.

(Means for Solving the Problems) The present invention takes the following means to solve the above problems. That is, the present invention provides a composite fiber comprising a core-sheath type conductive composite fiber in which the sheath part is made of a thermoplastic polymer and the core part is made of a metal having a melting point lower than the melting point of the thermoplastic polymer, and a non-conductive fiber. The fiber yarn has an area ratio of the core in a cross section of the core-sheath type conductive composite fiber of 0.2% to 0.2%.
50%, the variation rate of the area of the core in the longitudinal direction of the yarn is 25% or less, the core is substantially connected in the longitudinal direction of the yarn, and the core-sheath type conductive conductive material in the mixed fiber yarn is The proportion of the composite fiber is 0.25% to 46% by weight,
Both the non-conductive fiber and the core-sheath type conductive composite fiber have a boiling water shrinkage rate of 15% or less, and the difference in boiling water shrinkage rate between the two is 0% to 1.
A conductive mixed yarn characterized in that the content of the conductive fiber is in the range of 5%, and a thermoplastic polymer are supplied to the sheath of the spinning nozzle, and a molten metal having a melting point lower than that of the thermoplastic polymer is supplied to the spinning nozzle. A core-sheath type conductive composite fiber is spun by supplying pressure to the core so that the area ratio of the core to the sheath is 0.2% to 50%, and heating the core component to a temperature above its melting point. After that, it is hot-stretched at a draw ratio of at least 2.5 times or more so that the ring water shrinkage rate is 15% or less, and the obtained core-sheath type conductive composite fiber is drawn so that the difference in boiling water shrinkage rate is 0% to 15%. In combination with non-conductive fibers having a spring water shrinkage rate of 15% or less, the weight ratio (%) of the former and the latter is 0.25 + 99.75 to 4.
A method for producing a conductive mixed fiber yarn characterized by mixing the fibers as much as 6:54 is a means for solving the above problem. It is something.

The present invention will be explained in detail below.

First, the thermoplastic polymer constituting the sheath of the core-sheath type conductive composite fiber used in the present invention may be any fiber-forming polymer that can be melt-spun.Specific examples of such polymers include polyethylene terephthalate and polyethylene terephthalate. Examples include polyesters such as butylene terephthalate, polyamides such as nylon 6 and nylon 66, polyolefins such as polyethylene and polypropylene, and polymers containing these as main components.

Further, the thermoplastic polymer of the sheath portion may contain arbitrary additives such as a matting agent, a coloring agent, and an oxidation stabilizer, if necessary.

In particular, considering the whiteness and dyeability of the conductive composite fiber, polyester and nylon containing 1% to 3% titanium dioxide are preferred as thermoplastic polymers.

Further, specific examples of the low melting point metal constituting the core of the core/sheath type conductive base fiber used in the present invention include indium (In),
There are metals such as selenium (Ss), tin (Sn), bismuth (Bi), lead (Pb), and cadmium (Cd), as well as binary, ternary, and quaternary alloys made of these metals.
Specific examples of alloys include Bi/Sn, Bi/In5S
n/Pb,, B115n/In, Bi/Pb/Cd
.

Bi/Pb/Sn, Bi/S+/In/Pb, Bi
/Sn/Pb/Cd, Bi/Sn/■mouth/Pb/C
Examples include d.

Next, the melting point of the metal in the core must be lower than the melting point of the thermoplastic polymer in the sheath.

This is because the metal that forms the core cannot be supplied in a uniformly molten state during composite spinning, and as a result, it is not only difficult to obtain the desired conductivity, but also the quality of the thread is insufficient. It is.

The melting point Mc of the metal in the core is preferably lower than the melting point of the thermoplastic polymer in the sheath and in the range of 70°C≦Mc≦130°C. It becomes difficult to draw the fiber, and on the other hand, if Mc is smaller than 70°C, it becomes difficult to solidify the core metal during spinning, resulting in an unstable phase equilibrium state, which is not preferable, and the melting point cannot be measured. is by differential scanning calorimetry (OSC).

Furthermore, in the core-sheath type conductive composite fiber used in the present invention, the area ratio occupied by the core in the cross section of the core-sheath type conductive composite/synthetic fiber, the rate of variation in the length direction, the continuity, etc. of the composite fiber The area ratio of the core is 0.2% to 50%, but considering the thread properties, dyeability, etc., it is 0.5% to 40%,
Furthermore, the variation rate in the longitudinal direction of the core area, which is preferably 0.5% to 30%, is 25% because it affects the yarn physical properties of the composite fiber.
% or less, and particularly preferably 10% or less.

In addition, the core must be substantially connected in the longitudinal direction of the thread, where "substantially connected" means:
This means that the total number of discontinuities per meter is 5 cm or less.

If the total number of discontinuous parts per In is 51 or less, there is no problem in electrical conductivity, but it is preferably tel or less.

If the number of discontinuous portions per meter exceeds 51 according to the present invention, the conductive performance will not only deteriorate, but also the yarn will have uneven physical properties, which is not preferable.

The conductive mixed fiber yarn of the present invention has the above-mentioned core-sheath type conductive composite #a
It is a mixed fiber yarn consisting of fibers and non-conductive fibers, and the spring water shrinkage rates of the two and the difference between the two are important in the present invention, and the spring water shrinkage rates of both are preferably 15% or less. should be 11% or less. And the difference in spring water contraction rate between the two is,
In the range of 0% to 15%, preferably in the range of 0% to 11%, preferably the spring water shrinkage rate of the non-conductive fiber is higher.
If the spring water shrinkage rate of the core-sheath type conductive composite fiber exceeds 15%, the metal will not shrink uniformly, and the shape of the metal will be destroyed, the conductive performance will decrease, and the yarn properties will deteriorate, which is not preferable. On the other hand, the spring water shrinkage rate of non-conductive fibers is 15%.
If it exceeds , the shape stability of the fabric during post-processing will deteriorate, which is not preferable.

Furthermore, the difference in shrinkage rate of spring water is also set in the range of 0% to 15%.

If it exceeds 15%, the beauty of the dyed fabric will be significantly impaired, which is undesirable, and preferably from 0% to 11%. Further, it is preferable that the spring water shrinkage rate of the non-conductive fiber is greater than that of the core-sheath type conductive composite fiber.

The polymer forming the non-conductive fibers constituting the mixed yarn of the present invention must be the same, the same kind, or similar to the polymer forming the sheath of the core-sheath type conductive composite fiber. For example, combinations of polyamides such as nylon 6, nylon 66, nylon 46, and nylon 610, and combinations of polyesters such as polyethylene terephthalate, modified polyethylene terephthalate, and polyethylene terephthalate are preferred from the viewpoint of properties and yarn properties.

Further, the proportion of the core-sheath type conductive composite fiber in the conductive mixed yarn is 0.25% by weight to 46% by weight. In addition, in terms of volume ratio, 0.1% to 30% is preferable.

If it is less than 0.25% by weight, it is unfavorable in terms of electrical conductivity, while if it exceeds 46% by weight, it is unfavorable in terms of yarn physical properties and dyeability.

Furthermore, the state of mixed fibers in the present invention means a state of yarn doubling, twisting, fluid entanglement, electric mixing, and mechanical mixing. In any case, it is desirable to integrate them by appropriate means so that they do not separate; for example, it is effective to heat them or entangle them using air jets. The number of twists for this purpose is 10 twists/m or more, especially 20~
Approximately 500 times/m is suitable. Similarly, the number of entanglements is preferably 10 or more, particularly about 20 to 100/m.

Furthermore, in order to strengthen the integration of synthetic fibers, it is effective to bond the fibers together using a suitable adhesive.

Such adhesion can be done by a normal method, and there are no particular limitations. The fineness of the core-sheath type conductive composite fiber is, for example, 5 to 100 deniers, and the number of constituent filaments is 1 to 3.
Similarly, the fineness of non-conductive fibers is about 5 to 3.
It is often preferable that the filament has a diameter of about 0.00 denier and the number of constituent filaments is about 1 to 100.

Next, the method for manufacturing the conductive mixed fiber yarn of the present invention will be specifically explained using the drawings. FIGS. 1, 2, and 3 show one embodiment of the apparatus for manufacturing the conductive mixed fiber yarn of the present invention!
It is a schematic sectional view of an example. In Figure 1, the melting tank 5
The molten metal is transferred to a melting tank 6 by a gear pump 4, and the level of the melting tank 6 is controlled to be constant.

Next, the melting tank 5.6 is pressurized with an inert gas 10 at a constant pressure of 0, 1 to 10 kg/cj・G controlled by the control circuit 3, power amplifier 2, and electric control pulp 1, and a constant amount of molten metal is 12 is supplied to the spinning nozzle 8, and a thermoplastic polymer having a higher melting point than metal and a core/sheath ratio of 0.2:99 are supplied.
．． 8 to 50: Composite to give 5G to produce conductive composite fiber 90 The spinning speed during spinning in the present invention is preferably in the range of 600 to 2000 m7 min considering the final yarn quality, core-sheath type. The conductive fiber 19 is spun in the form of 7 multifilament yarns or monofilaments. The fibers are then sent to a mixing roller 16. Normal stretching methods can be used to stretch conductive composite fibers, but it is necessary to heat the core component to a temperature above its melting point using a heating roller or the like before stretching.
If the fiber is stretched without this step, the core component will be significantly broken and unevenness will occur in the yarn quality, which is undesirable.The stretching ratio should be 2.5 times or more, preferably 2.7 times to 4.0 times.

Further, the temperature of the heater 15 is 130°C or higher, preferably 15°C.
The temperature shall be 0 to 200°C.

On the other hand, the non-conductive fiber 18 is sent to the roller 16 for doubling through the roller 17, where it is mixed with the drawn core-sheath type conductive composite fiber at a weight ratio of 99.75:0.25 to 54246. Then, the two types of fibers are further heated by a ring twisting method 19 to integrate the two types of fibers.

(Example) The present invention will be described below with reference to Examples, but the present invention is not limited to the Examples. Each characteristic in the Examples was measured by the method shown below.

■Strength and elongation were measured using a tensile tester.・Strength (g/
d) is the cutting strength when elongated at a rate of 100%/min.

- Elongation (%) is the cutting strength when elongated at a rate of 100%/min.

■ Mixing ratio of core component This is the area ratio (%) to the total cross-sectional area of the composite fiber observed with an optical microscope.

(2) Continuous length of the core component This is the total length (1) per 1 m of the side surface of the composite fiber observed with an optical microscope.

(2) Electrical specific resistance Measured by connecting the side surface of the mixed fiber to a metal using a conductive mixed fiber yarn at 25° C. and 65% R11, and applying a DC voltage of IOV (Ω·1, yarn length 5C1).

■ Triboelectric charge amount Mixed fiber yarn and plied yarn are sewn into white twill using processed polyester yarn (1 thread/10 ■), JI at 20℃, 30%■
Measured by SL-1094-1980 method (μC/
but).

■ Dyeability Mixed fiber yarn and plied yarn were sewn into white twill using processed polyester yarn (1 yarn/10m), and dyed with disperse dye under the following conditions, and the dyeability was visually measured.

Dianix Blue EC-w 2χ 01
1 f130℃
5-X3m) and measured with a color difference meter. L value, a value, b
It is a value.

Example-■ [η)-0.85, polyethylene terephthalate containing 2% titanium oxide as a sheath component and an alloy (bismuth/tin/indium system) with a melting point of 78.8°C) was used as the first Using the equipment shown in the figure, melt and pressurize (N-rich gas, 0.40 kg/cj) L, and supply it to the composite nozzle shown in Figure 2, and perform composite spinning at a spinning temperature of 285°C and a spinning speed of 700 m/min. After that, use a preheating roller (85℃) and a heater (15℃).
The film was stretched 2.5 times using a stretching machine equipped with a temperature of 0°C.

The resulting composite fiber had a denier of 18 d (monofilament), a strength of 3.1 g/d, and an elongation of 38%.

In addition, the area ratio occupied by the core in the cross section of the composite fiber is 1
At 0.0%, the total number of discontinuities per 1 m of the core length was 0.20. Moreover, the rate of variation in the area of the core is 2
%Met.

Next, by the method shown in FIG.
Denier 15 filament, strength 4.8g/d.

Drawn yarn (non-conductive) of polyethylene terephthalate (containing 2% titanium oxide) with boiling water shrinkage rate of 8% and number of twists of 50T/M
The yarn was combined and twisted to obtain a mixed yarn.

Comparative Example-1 Composite spinning and drawing were carried out under the same conditions as in Example-1 (denier 15 d1 strength 4.5 g/d, elongation 40%, area ratio occupied by core 0.1%, area variation rate 33%) , the boiling water shrinkage rate is 8%, and the total number of discontinuous parts per 1 m in the length direction of the core is 10C11) Using a core-sheath type conductive composite fiber, Example-1
Same as Example 1 under the conditions shown in Example 1 with non-conductive fiber and weight%
A conductive mixed fiber yarn was obtained by twisting and twisting.

Comparative Example-2 Conductive composite fiber obtained by composite spinning and drawing under the same conditions as Example-1 (denier 30 d, strength 2.3 g/d
, the elongation is 25%, the area ratio occupied by the core is 65%, the area variation rate is 8%, the total number of discontinuous parts per 1 m in the length direction of the core is O
,, 5 cm) and was twisted with 50% by weight of non-conductive fibers under the conditions shown in Example 1 to obtain a mixed fiber yarn. Example-
1. The properties of the mixed fiber yarns obtained from Comparative Example-1 and Comparative Example-2 are shown in Table 1.

Table 1 Agriculture - 15 mowing 0" 76.3 - 0.91.0
'In Table 1, Comparative Example-1 has a small amount of core alloy in the core-sheath type composite fiber, so the hue and dyeing are good, but the conductivity is very low. Because of the large amount, although it has conductivity, the hue and dyeability are poor compared to w4M. In contrast, the material of Example 1 of the present invention had favorable conductivity and hue, and also had excellent dyeability.

Example 2 Conductive composite fibers with iron 6 sheathed under the same conditions as Example 1 (denier 6d, strength 2 g/d, elongation 50%)
, the area ratio occupied by the core is 8%, the area variation rate is 3%, the fresh water shrinkage rate is 8%, and the total discontinuous part per 1 m of the core length is 0.5 CI), and 24 denier / 4 A filament having a strength of 3 g/d and boiling water shrinkage and heavy water shrinkage rate of nylon 6 was combined and twisted at 20% by weight in the same manner as in Example 1 to obtain a mixed fiber yarn. This blended yarn and 75 denier/26 filament (0 titanium oxide)
．． (containing 5%) polyethylene terephthalate drawn yarn 2 Kishichi was combined and twisted at a twist number of 150 twists/M.

Conventional example 1 Commercially available conductive fiber using nylon 6 (conductive layer: carbon
A plied and twisted yarn was obtained in the same manner as in Example 2 using (black).

Conventional Example 2 A plied and twisted yarn was obtained in the same manner as in Example-2 using commercially available conductive fibers (conductive layer: metal compound) using nylon 6. Example-
2. Table 2 shows the characteristics of the conductive mixed fiber yarns used in Conventional Example 1 and Conventional Example 2, and the characteristics of the twisted yarns obtained from Example-2, Conventional Example 1 and Conventional Example 2 using polyester processed yarn. Table 3 shows the conductivity and dyeability of the fabric sewn into the white twill.

Table 2 Conventional Example 1 24d/4f 1.8 150 140' 43.4-1.13.7 Table 3 Conventional Example 1 2.0 Significant difference from base fabric, black streaks From Tables 2 and 3 Although conventional example 1 has good conductivity,
The yarn quality was poor, such as low strength and too high elongation (and the hue of the fabric (after dyeing) was also poor. Conventional Example 2 had poor yarn quality such as high elongation, and poor conductivity. Example -・2 had good thickness conductivity and good yarn quality and hue.

Example 3 Composite spinning and drawing were carried out in the same manner as in Example 1 except that only the supply pressure of the molten alloy was changed. Thereafter, the obtained core-sheath type conductive composite fiber was combined and twisted with non-conductive tsIl by the method shown in Example 1 to obtain a mixed yarn.

The staining properties of each are shown in Table 4.

If it deviates from the range of the present invention, the degree of eye peeling of the dyed product will deteriorate significantly. However, those that satisfied all the requirements of the present invention had no unevenness in the dyed product and had excellent dyeing properties.

(Effects of the Invention) The conductive mixed fiber yarn of the present invention is made of a mixture of core-sheath type conductive composite fibers and non-conductive fibers in which the mixture ratio of the core made of a low-melting point metal and the shape in the length direction are sufficiently controlled. As a result, it has excellent properties in terms of not only conductive performance but also yarn physical properties, hue, and dyeability.The conductive mixed fiber yarn of the present invention can be used to produce antistatic work clothes, uniforms, carpets, car seats,
It can be used as an electromagnetic shielding material.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of an embodiment of a molten metal supply device used in the production of core-sheath type conductive composite fibers used in the present invention, and FIG. FIG. 3 is a schematic cross-sectional view of an embodiment of a device for mixing conductive composite fibers and non-conductive fibers. Electric control pulp, control circuit, melting tank, pressure gauge, conductive composite fiber, thermoplastic polymer, roller heater, roller spindle, power amplifier gear pump melting tank composite nozzle inert gas molten metal preheating roller loaf - non-conductive fiber

Claims (1)

[Scope of Claims] 1. A core-sheath type conductive composite fiber whose sheath portion is made of a thermoplastic polymer and whose core portion is made of a metal having a melting point lower than the melting point of the thermoplastic polymer, and a non-conductive fiber. The mixed fiber yarn is such that the area ratio of the core in the cross section of the core-sheath type conductive conjugate fiber is 0.2% to 50%, and the rate of variation in the area of the core in the longitudinal direction of the yarn is 25% or less, the core portion is substantially connected in the longitudinal direction of the yarn, and the proportion of the core-sheath type conductive conjugate fiber in the mixed yarn is 0.25% to 46% by weight, A conductive mixed fiber yarn characterized in that both the non-conductive fiber and the core-sheath type conductive composite fiber have a boiling water shrinkage rate of 15% or less, and a difference in boiling water shrinkage rate between the two is in the range of 0% to 15%. . 2. A thermoplastic polymer is supplied to the sheath of the spinning nozzle, and a molten metal having a melting point lower than the melting point of the thermoplastic polymer is supplied to the core of the spinning nozzle, so that the area ratio of the core to the sheath is 0. A core-sheath type conductive composite fiber is spun by supplying it under pressure so that it is 2% to 50%, and then the core component is heated to above its melting point and then hot-stretched at a draw ratio of at least 2.5 times. The resulting core-sheath type conductive composite fiber is combined with a non-conductive fiber having a boiling water shrinkage rate of 15% or less so that the difference in boiling water shrinkage rate is 0% to 15%. The weight ratio (%) of the former and the latter is 0.25:99.7
A method for producing a conductive mixed fiber yarn, characterized in that the fibers are mixed at a ratio of 5 to 46:54.