JPS6227192B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to conductive fibers and methods for producing the same.

More specifically, the present invention relates to a conductive fiber formed by providing a transparent conductive coating mainly made of cuprous iodide on the surface of a synthetic fiber, and a method for producing the same. Conductive fibers are widely used as materials for work clothes, carpet belts, etc. because they have the effect of suppressing the chargeability when used as they are or mixed with ordinary chargeable synthetic fibers or natural fibers.

Conventionally, antistatic methods for synthetic fibers include incorporating antistatic agents such as anionic, cationic, or nonionic surfactants with low electrical resistance, and hydrophilic polymers during the fiber manufacturing process, and There are methods of sewing or applying an antistatic agent as a post-processing treatment after sewing. In such a method, the antistatic effect appears when the antistatic agent adsorbs moisture in the air and reduces electrical resistance. Therefore, it is highly dependent on humidity and has little effect in low humidity environments.

Furthermore, since the antistatic agent was washed away by washing, the washing resistance was poor, especially in those that were subjected to post-processing.

In addition, as other antistatic methods, conductive fibers made by coating metal fibers such as steel or synthetic fibers with conductive powder such as silver powder or carbon can be inserted into synthetic fibers, or into cloth made of synthetic fibers. There is a way to mix a small amount into

Although the products obtained by this method have no humidity dependence and have an antistatic effect even in low-humidity environments, they are colored and their appearance will be significantly impaired when mixed with synthetic fibers. Furthermore, metal fibers such as steel have drawbacks such as lack of durability against washing.

As a result of intensive research into excellent conductive fibers free from such drawbacks, the present inventors have found that cuprous iodide is an excellent conductive fiber as a coating to be provided on the surface of the synthetic fiber that serves as its base material. ,and,
We discovered that a cuprous iodide coating can be made by chemically plating copper and then iodinating it to form a uniform transparent conductive coating on the surface of fibers.
We have arrived at the present invention.

That is, the present invention provides (1) a conductive fiber in which a transparent conductive coating mainly made of cuprous iodide is continuously provided on the surface of the synthetic fiber in the longitudinal direction; A conductive material characterized by forming a metal film mainly made of copper on the surface continuously in the longitudinal direction by chemical plating, and then converting the film into a film mainly made of cuprous iodide by an iodination reaction. It is a method of manufacturing fibers.

Examples of the synthetic fibers used in the conductive fibers of the present invention include synthetic polymers such as polyacrylonitrile, polyester, polyamide, and polyolefin, or derivatives derived from these synthetic polymers,
Blend fibers containing these synthetic polymers as main components can be used, but polyacrylonitrile fibers are particularly preferably used from the viewpoint of adhesion to the transparent conductive coating.

These synthetic fibers may have irregular cross-sections, and may be previously subjected to woolly processing, corona discharge treatment, or surface treatment for the purpose of improving adhesion, appearance, dyeability, etc. It may be dyed or contain pigments.

Further, the synthetic fiber used in the present invention has a denier of 2 to 100, preferably 5 to 50 denier per single yarn, from the viewpoint of antistatic properties and ease of handling.

Examples of methods for providing a transparent conductive film of cuprous iodide on the surface of synthetic fibers include (1) providing a copper film by vacuum evaporation, sputtering, chemical plating, etc., and then iodinating this film; Method.

(2) A method of sputtering copper iodide.

(3) Methods such as vacuum evaporation or sputtering of copper in an iodine atmosphere may be listed.

The conductive fiber of the present invention may be obtained by any of these methods, but in particular, a metal coating consisting mainly of copper is provided on the surface of the synthetic fiber by a chemical plating method, and then this coating is coated with iodine. The conductive fibers obtained by this method have excellent antistatic properties and durability because the cuprous iodide coating is uniformly provided around the fibers.

In the method of providing a metal coating mainly made of copper and then iodinating it, if the metal coating is too thin, it will not have sufficient conductivity and durability, and if it is too thick, it will be difficult to completely iodine, and the transparency of the coating will decrease. Sexuality is impaired. From this point of view, the appropriate thickness of the metal coating mainly consisting of copper is 50 to 5000 Å, preferably 200 to 1000 Å.

The main component of the metal coating must be copper, but it may contain other metals as long as the desired effects of the present invention are not impaired.

Chemical plating can be carried out by immersing synthetic fibers in a chemical plating bath, but the surface of the synthetic fibers must be washed, degreased, sensitized, activated, mechanically etched, chemically etched, or hydrophilically etched beforehand. Surface treatment such as resin coating improves the wettability of synthetic fibers with the plating bath and improves catalyst adsorption and adhesion.
Chemical plating is efficiently achieved, and the adhesion between the synthetic fiber and the plating film is improved. Any conventional method can be used for pretreatment of degreasing, sensitization, and activation, but it is preferable to use a neutral detergent or alkaline detergent for the degreasing step, and for the sensitization step, use of a stannous chloride-hydrochloric acid based sensitizer is preferred. Processing in a sensitizing agent is sufficient to achieve the purpose.

Further, the subsequent activation step is preferably carried out in a palladium chloride-hydrochloric acid type activator.

After pretreatment as necessary, the synthetic fibers are passed through a chemical copper plating bath to deposit copper metal. As the chemical copper plating bath, a copper salt-formalin bath is preferable.

The iodination reaction can be carried out by exposing synthetic fibers coated with copper to iodine gas, or by using a solution in which iodine is dissolved in a non-hydrophilic solvent such as benzene, toluene, carbon tetrachloride, or dichloroethane. This can be carried out by, for example, a method in which the synthetic fiber is soaked and then the solvent and excess iodine are removed by sublimation.

In this way, after forming a uniform copper coating on the surface of the synthetic fiber, an iodination reaction is carried out to convert the coating into a cuprous iodide coating, thereby making it possible to obtain an excellent electrically conductive fiber.

In addition, within the range that does not impair the intended effects of the present invention, a layer of an organic or inorganic polymeric substance or an organometallic compound may be provided as a top coat on the outside of the transparent conductive film of the present invention to improve wear resistance and chemical resistance. Properties such as durability and washing resistance may be improved.

Examples of organic or inorganic polymeric substances used for this purpose include polyvinylidene chloride, polyvinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyester, polycarbonate, polyurethane, polystyrene, polyamide, polyacrylonitrile, and acrylonitrile.
Butadiene-styrene copolymer, epoxy resin,
Examples include triazine resins, diallyl ester resins, silicone resins, phenolic resins, unsaturated polyester resins, melamine resins, organopolysiloxanes and urea resins.

Among these, epoxy resins, triazine resins and polyvinylidene chloride-acrylonitrile copolymers are particularly preferably used.

Examples of the organometallic compound include alkyl titanates such as tetrabutyl titanate. The top coat must be adjusted to a thickness that does not impair surface conductivity. The upper limit of the film thickness is 3 μm, but the film thickness is preferably 0.5 μm or less.

Hereinafter, details of the present invention will be shown in Examples.

Example 1 and Comparative Example 1 A 15-denier polyacrylonitrile monofilament was washed with a neutral detergent, washed with water, and sequentially treated in a stannous chloride-hydrochloric acid sensitizing bath, a water washing bath, and a palladium chloride-hydrochloric acid activating bath. Pretreatment for sensitization and activation is performed by passing through immersion.

After washing with water, the filament was passed through a formalin-copper sulfate/tartrate chemical copper plating bath to provide a uniform copper coating with a thickness of 600 Å. After washing with water and drying, it was wound onto a bobbin. Subsequently, the bobbin was set in an iodination reaction tank. After evacuating the reaction tank,
Iodine gas generated outside the reaction tank was passed through a trap filled with a desiccant using nitrogen gas as a carrier to remove moisture, and then introduced into the reaction tank.

Next, by adjusting the pumping speed and the amount of gas introduced, the copper-coated filament was exposed to an iodine atmosphere to carry out an iodination reaction while maintaining the degree of vacuum in the reaction tank at around 10 Torr, converting it into a cuprous iodide coating. After that, I wound it onto another bobbin.

The electrical resistance value per cm of the obtained conductive fiber was 1.2 MΩ, and the appearance was white and almost unchanged from before the conductive treatment.

One of these conductive fibers and four single 15-denier polyethylene terephthalate fibers were twisted together and sewn into a 20 cm x 30 cm polyethylene terephthalate cloth in a grid pattern at 2 cm intervals. The resulting cloth was left in an atmosphere of 20°C and 30% humidity for 16 hours, then placed on an acrylic cloth and rubbed the surface with another acrylic cloth 10 times, and then exposed to a rotating sector electric field. When the electric potential was measured with a meter (Rion E-1041 model), it was 5KV. For comparison, a Tetron cloth without the conductive fibers of the present invention was rubbed under the same conditions and the charged potential was measured, and it was 50 KV.

Example 2 and Comparative Example 2 A 10 denier polyethylene terephthalate monofilament was immersed in an acetone solution of nitrile rubber and phenolic resin (solid content 10% by weight),
It was then dried and cured to form a resin-coated monofilament. After performing sensitization and activation treatment in the same manner as in Example 1, it was immersed in a copper plating bath,
A uniform copper coating with a coating thickness of 800 Å was provided. After washing with water and drying, it was wound onto a bobbin. The copper-coated filament was then immersed in a toluene solution of iodine (10% by weight) and then dried to remove the toluene and excess iodine, converting the copper coating to a cuprous iodide coating to obtain a conductive fiber. Ta.

The electrical resistance value per 1 cm of the obtained conductive fiber was 900 KΩ, and the appearance was white and almost unchanged from before the conductive treatment.

The antistatic property of this conductive fiber was measured in the same manner as in Example 1, and the triboelectric potential was 4 KV.

For comparison, Metalian fiber (manufactured by Teijin Ltd.)
When conductive fibers were similarly sewn into white polyethylene terephthalate cloth at 2cm intervals,
The seams were very noticeable.

Example 3 Conductive fibers were obtained by repeating Example 2, except that a 15 denier 6-nylon monofilament replaced the polyethylene terephthalate monofilament and the copper coating thickness was 500 Å.

The electrical resistance per cm of the obtained conductive fiber is
It was 2MΩ.

Example 4 The conductive fibers of Example 3 were sewn into a 20 cm x 30 cm polyethylene terephthalate cloth in a grid pattern at 2 cm intervals in the same manner as in Example 1.

In addition, for comparison, a cloth with stainless steel wire sewn in was made using the same method. Even after washing the cloth sewn with the conductive fibers of the present invention 40 times, the charged potential remains the same.
There was almost no change at 6KV from before washing (5KV), indicating excellent washing resistance. On the other hand, cloth with stainless steel wire sewn into it begins to lose its antistatic properties after several washes, and the electrostatic potential after 40 washes is
It was 40KV and had poor washing resistance.

Claims (1)

[Claims] 1. An antistatic cloth for clothing, which is made by weaving and/or sewing conductive fibers in which a transparent conductive coating mainly made of cuprous iodide is continuously provided on the surface of synthetic fibers in the longitudinal direction.