JPS5860015A - Preparation of electrically conductive composite fiber - Google Patents

Abstract

PURPOSE:To obtain the titled fibers having improved electric conductivity, by forming fibers from a mixture of a fiber-forming thermoplastic polymer with a stannic oxide electrically conductive substance and a thermoplastic polymer having a lower melting point than the polymer, drawing the fibers, and heat- treating the drawn fibers. CONSTITUTION:A mixture of (A) of fiber-forming thermoplastic polymer, e.g. polyethylene therephthalate, with (B) (i) a stannic oxide electrically conductive substance and (ii) a thermpolastic polymer having a lower melting point than the polymer (A), e.g. polyester, polyamide or polyether, is formed into electrically conductive fibers, which are then drawn and heat-treated at a temperature of the melting point of the thermoplastic polymer in the component (B) or above and 30 deg.C or more lower than the melting point of the component (A) preferably for 10min or longer to give the aimed fibers. Preferably, the area ratio of the component (B) in the cross section of the aimed fibers is 1-50%, and the amount of the stannic oxide electrically conductive substance in the component (B) is 50-75wt%.

Description

[Detailed description of the invention]

The present invention uses a conductive material as conductive material.

[Novel conductive composite lil containing tin oxide-based conductive powder
Concerning the manufacturing method of complexes. Synthetic twill wire 1 For example, polyester-based fibers, boria-based fibers, etc. have low conductivity, so static electricity is generated and roars. A high potential charge is observed, which can lead to dust adhesion and various problems associated with discharge. In order to solve this problem, it is known to mix conductive edge wires into textile products, and conductive m-fibers include metal fibers and metal-plated fibers. #1 boats coated with a polymer dope containing a conductive substance, edge lines coated with carbon black, etc. have been proposed. However, these conventional conductive embroideries. All of them had serious drawbacks and were not satisfactory.For example, metal fibers do not have flexural recovery properties, so their conductive performance deteriorates due to flexing during use or processing. Mixed, interlaced. It has many disadvantages, such as that the mixed weave is not good quality and furthermore, it has a color tone peculiar to metal. For fibers coated with metal plating, it is necessary to form a uniform and continuous plating layer on the edge line mK. llllI table WK requires smoothness, the type of twill wire that can be applied is thick (limited), plating must be done precisely, and the manufacturing cost is extremely high (
It has many drawbacks, such as the plating layer being easy to peel off during use or processing (low durability, and even exhibiting a color characteristic of metals). Fibers also have the same disadvantages as metal plating am mentioned above in terms of manufacturing cost, peeling, etc.Furthermore, carbon black-containing fibers are colored black with carbon black, and when mixed with synthetic iron, the appearance will be significantly impaired. However, it has a fatal drawback that its field of use is limited.As a result of intensive study to provide conductive IIIM without the above-mentioned drawbacks, the present inventors have found that oxidized nitride, which has lower electrical resistance, is used as a conductive material. Focusing on the use of tin-based conductive substances, #II shadow-forming thermoplastic resin (mu) component]
A thermoplastic resin containing a tin oxide-based conductive substance [(
When we tried to manufacture a composite III weave using component B), we found that undrawn yarn showed sufficient conductivity, but when stretched to increase yarn strength, the conductivity decreased and the stretching ratio was increased. Accordingly, the conductive performance deteriorates significantly. For this reason, it was not possible to draw at a sufficient magnification, and it was not possible to obtain a conductive composite edge line that was excellent in both yarn strength and conductivity. Therefore, as a result of repeated studies on the thermoplastic polymer in which the stannic oxide-based conductive substance in component (B) is blended, it was found that this polymer is a thermoplastic polymer having a melting point 40°C or more lower than the melting point of the prisoner component. It has been discovered that conductive performance, which had been significantly reduced during stretching, can be recovered by selecting and heat-treating at a temperature higher than the melting point of the polymer in the component (after stretching), preferably at least 10°C higher than the melting point, and the present invention. completed. That is, the present invention provides a mixture of a #I shadow-forming thermoplastic polymer component, a stannic oxide-based conductive substance, and a thermoplastic polymer having a melting point 40° C. or more lower than the melting point of component (2). Conductive composite #J# formed from the following components:
A process for producing conductive composite #I, which is characterized by heat treatment at a temperature higher than the melting point of the thermoplastic polymer and 30°C or lower lower than the melting point of the component (2). The polymer serving as component (3) constituting a part of the conductive can fiber of the present invention may be a pII-forming polymer that can be melt-spun. Specific examples of such a polymer include: refers to polyesters such as polyethylene terephthalate and polybutylene terephthalate, bolyalides such as Nylon 6JP Nylon 6@, polyolefins such as polyethylene and polypropylene, and copolymers or mixed polymers containing these as main components. In addition, the polymer constituting component (A) may contain optional additives, such as a matting agent, a coloring agent, an oxidation stabilizer, and a dyeing improver, as required. In addition, component (3) constituting the conductive part of the conductive part of the present invention is composed of a conductive fine powder of II oxide whose volume resistivity is adjusted to 10"Ω·1 or less and a thermoplastic polymer. For conductive weave used in electrical applications, to”O/x, preferably 1611Ω/c for a DC voltage of 1kV.
Since an electrical resistance of less than m is required, the volume electrical resistance of component (B) must be less than 10"Ω/flaw, and the volume electrical resistance of the conductive fine powder itself to be blended must be less than 101 ohm/flaw. Therefore, conductivity is insufficient when using stannic oxide alone. Any method can be used to adjust the volume resistivity of tin oxide to 10"Ω·1 or less. For example, there is a method in which a trivalent antimony compound such as antimony (III) chloride or antimony trioxide is added to tin oxide and fired at a high temperature. In this way, along with the stannous oxide-based conductive mold powder whose volume resistivity is adjusted to 10'Ω. , preferably has a melting point lower than SO°C, has thermal stability that does not cause decomposition etc. at the spinning salinity, and is melt extrudable, so that it itself has a tightening ability. (If the melting point difference between the polymers in the m component is less than 40°C, a decrease in am strength and fusion between embroideries will occur during the heat treatment after stretching, which will be described later). Specific examples of the polymer in such a component include polyester, polyamide, polyether, polyolefin, or a polymer containing these as main components. Any method can be used to mix the tin-based conductive material as long as it can be dispersed well.The amount of the tin oxide-based conductive material to be mixed varies depending on the required conductivity mK. However, (in order to make the volume electrical resistivity a of the Bl component 10'Ω·1 or less, it is necessary to increase the SO weight % or more. On the other hand, if the amount of tin oxide-based conductive material mixed is too large, (2) Ingredients
Also, since spinning becomes difficult, it is appropriate to set the weight to 75 and 5 or less. In addition, optional additives such as a matting agent, a coloring agent, an oxidation stabilizer, etc. can also be included in the component (8), depending on the requirements. Upper li! Conjunction II composed of prisoner component component component component
The shape of the II fiber may be any shape as long as (2) the component is continuous along the # wire axis direction; however, (BI
The core-sheath type, in which 1 minute of Ji is completely wrapped by the K(A) component, has inferior anti-static performance when drying compared to the shape where a section of 11 minutes of Ji is exposed on the surface of the # wire, so it is not suitable for carpet applications. For next-layer applications that require more demanding performance,
A shape in which at least a portion of the El component is exposed on the surface of the thin wire is preferred. In addition, the combination of polymers used for the 03) l1 component may be arbitrary in the case of complete core-1II11, but in the case of a partially exposed layer, the same type of polymer may be used to prevent peeling. It is preferable to use In addition, the ratio of component (4) and component (1) in the III cross section can be within an extremely high range, but if the ratio of component (1) becomes too large, the resulting conductivity #I
Since the strength of IIm decreases, the area occupied by component (6) in the cross section of the thin wire is preferably 60% or less.
In addition, the lower limit of this (11 components) is that 51 minutes only need to be continuous along the m-line axis direction, and there is no need to provide it at q#, but it is usually 1% or more in terms of area in the embroidery cross section, especially 3%
It is preferable to do the above. A special method for producing such composite 11I fibers. It is not necessary to adopt these conditions, and the melt spinning method and conditions for producing composite #- consisting of two components can be arbitrarily applied depending on the component (3). In the present invention, the spun fibers are stretched to obtain sufficient strength. Any method and conditions for this stretching may be used as appropriate. As mentioned in tIjK, the conductive composite fiber of the present invention does not have sufficient conductive performance when normally spun and stretched by Jg. The necessary electrical conductivity can be achieved by heat treatment at a temperature of 10°C or higher.However, heat treatment near the melting point of the polymer component, which is the main polymerization of Composite III,
In order to cause a decrease in the strength of am and fusion between 111111, the heat treatment temperature needs to be 30° C. or more lower than the melting point 2 of the polymer as the prisoner component. Any means may be employed for such heat treatment after stretching. In addition, in order to sufficiently recover the conductive performance degraded by stretching, k requires a processing time of at least X10 minutes, but the effect is saturated even if it continues for more than 30 minutes, so a diameter of up to so5+ is appropriate. The conductive chain line of the present invention uses a highly white charcoal-based stannic oxide powder as the conductive substance, and has the (2) component part that forms the usual synthetic III matrix, so it has excellent IIIA properties. It has white charcoal and sufficient strength, can be dyed in any color by conventional methods, and its conductive performance does not deteriorate during processing or use, eliminating all the drawbacks of conventional conductive embroidery. It can be applied to any field where conductive performance is required. The present invention will be further explained in detail with reference to Examples below. The measurement conditions for the volume resistivity of the conductive composition and conductive #I fabric in Examples were 20° C. and no% RH. j kV DC voltage. Also, the volume m of conductive fine powder
tlr, I[III Constant conditions Gt z o℃, s
The melting point of the 0 polymer under o%*H, 3 vilfi voltage, and aooktt/d pressure was determined using a DuPont SOO differential thermal analyzer. Example 1 Polyethylene (Ube Kozui KK Fake J 3511. Melting point ti
o℃) 100 parts by weight and tertiary tin oxide-based conductive fine powder (average rice grain diameter Q, 4J, volume resistivity 8×100・ca) 1
s and 6 parts by weight were melted and combined for 30 minutes at ZSO° C. under a nitrogen stream at normal pressure to obtain a conductive composition having a volume resistivity of tsxio'Ω·1. The above conductive composition is used as component (B), polypropylene (
S-mesh SM manufactured by Ubeko 11kk, melting point 171°C) was used (with a spinneret having 1 side-by-side spinning hole (aS φ) as a local component, and once spun at zso°C and spinning speed. 4SO denier at 400 m/min, the area ratio of the lead component and (2) component in the cross section of the wire machine is 4 = 1, and the surface area is approximately 1
6% of the ml component is a non-woven composite j! I got embroidery. The electrical resistance value of this unstretched composite J11J11 was 7.0×IOΩ/wound.Then, it was stretched 10 times at a stretching temperature of 120°C. The electrical resistance value of the obtained Tsumugi Shinaya wire is 10110
71 or higher, and its conductive performance was significantly reduced. When this jlIIIA was heat-treated at 140°C for 30 minutes, 1
Strength 250jl, elongation 30%, electrical resistance value a, oxto
A conductive wire cone of 'Ω/thin was obtained. Comparative Example 1 A 4-fold stretched composite fabric was produced in exactly the same manner as in Example 1,
This IIm was heat treated at 100° C. for 30 minutes. The electrical resistance value of the obtained fine woven fabric was L4X10''Ω/al+, and it was rejected as a conductive textile. ) too heavy weight and oxide II2 tin-based conductive material C average particle size α4A, volume resistivity 8×10Ω・cm)
1! 0 parts by weight of I under a nitrogen stream at normal pressure. Melt gold at ℃ for 30 minutes to obtain volume resistivity ζ4×10Ω”0
No. 11 conductive compositions were obtained. The above conductive composition is used as a component, and the intrinsic viscosity is a@Id・
/I polystyrene prephthalate (melting point 265°C) is used as the round component, and one concentric core-sheath spinning hole (aS cod φ) is prepared. Using a spinning nozzle with holes, spin the ingredients into the core lIK% (2
) component was applied to the limbus L, spinning AILHzso'c, spinning speed 400.111/min, 450 denier, and a composite material with an area ratio of f component and (l component of 4:1) in the cross section of the A fiber complex was obtained.The electric resistance of this undrawn composite Il fiber was 5×I G”Ω/1.Then, it was drawn 40 times at a drawing temperature of 120°C. The resistance value was 10IfΩ/a1 or more.
When Jll was heat treated at 1110℃ for 30 minutes, it became strong.
ssJI, 25% elongation comparison example! A 4-fold stretched composite am was produced in exactly the same manner as the actual 11 gHz sample, and this #hoko was heat treated at 140°C for 30 minutes, and the electrical resistance value of the obtained fiber was 1 ollΩ/flaw or more. Patent applicant Teijin Ltd.

Claims (1)

[Scope of Claims] (Component (1) consisting of an embroidery-forming thermoplastic polymer, a stannic oxide-based conductive substance, and a thermoplastic material having one point lower than the melting point of component (2) by 4°C or more. A conductive composite formed from the component (6) consisting of a conductive composite formed from the component (6), which is formed at one or more points of the flexible polymer in the CB component and at least 30°C lower than the melting point of the component (6) after being stretched. A method for producing a conductive composite fiber in which the conductive composite fiber is molded by heating at a temperature.A method for producing a conductive composite anchor according to claim 11, wherein the manufacturing time is short (both 10 minutes). - Claim 1, in which the area ratio occupied by the spring component in 1 ft HK horizontally of the conductive electrode covering s 1 m is 1 to sit%.
A method for producing a conductive composite fiber according to item 1 or item 112. (4@ The amount of the oxidized secondary conductive substance in the ingredients is SO
The method for producing a conductive composite fiber according to any one of claims 1 to 3, wherein the content is 7 i vt%.