JP2011001655A - Heat resistant electroconductive fiber, and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber equipped with electroconductivity and heat resistance jointly, capable of solving problems in that since a synthetic fiber tends to generate static electricity by friction as compared with a natural fiber, there are problems such that a clothing attaches to a body, absorbs dusts to be soiled or discharges on putting it on and off to give uncomfortable feeling, etc., also as compared with the natural fiber, since the synthetic fiber is weak to heat, it is necessary to impart the heat resistance in some uses, and also a material obtained by imparting an electroconductivity to the synthetic fiber melts more easily than the material not imparted with the same and tends to have inferiority in heat resistance, etc.SOLUTION: This fiber excellent in heat resistance and electroconductivity without damaging the performance of the fiber is obtained by covering the surface of a fiber having heat resistance with an electroconductive polymer.

Description

  The present invention relates to a heat-resistant conductive yarn capable of obtaining excellent heat resistance and stable conductive performance, and a method for producing the same.

  Synthetic fibers are generally more likely to generate static electricity due to friction than natural fibers, causing problems such as clothes clinging to the body, adsorbing dirt and getting dirty, and discharging and discomfort when attaching and detaching. there were. Further, synthetic fibers are weaker than heat compared to natural fibers, and it is necessary to impart heat resistance depending on applications. Moreover, what provided the electroconductive performance to the synthetic fiber exists in the tendency which is easy to melt | dissolve compared with the thing which is not provided, and is inferior in heat resistance, The fiber which has electroconductivity and heat resistance is calculated | required.

  Methods for imparting conductivity and heat resistance to synthetic fibers are broadly classified into a method for adding a conductive component and a heat-resistant component to the fiber itself, and a method for adding a conductive component and a heat-resistant component by post-processing. In Patent Document 1, an acrylonitrile copolymer obtained by copolymerizing 30 to 70% by weight of a halogen-containing vinyl monomer is added to 5 to 50% by weight of conductive fine particles (carbon black) with respect to the copolymer. ) -Containing acrylic fibers having excellent conductivity and flame retardancy. However, in this method, if excellent electrical conductivity and heat resistance are to be obtained, the content of halogen-containing vinyl monomers and conductive fine particles will be increased, resulting in a decrease in yarn-making properties, yarn strength, stretchability, etc. There were also problems with the environment and environmental problems during incineration, making implementation difficult.

  In Patent Document 2, a resin layer containing a flame retardant (a halogen compound, a phosphorus compound, a nitrogen compound, an antimony compound, or the like) is formed on the surface of an electrically conductive fabric, and the conductivity and flame resistance are thereby increased. Disclosed is a fabric having properties. However, this method is a processing method using a fabric, and there is no problem in industrial materials. However, this method is not suitable in a field where a hand feeling such as a woven or knitted fabric or a soft texture is required.

Further, Patent Document 3 discloses a conductive brush using a pile woven fabric having pile yarn as an electrically conductive brush for an image forming apparatus and using an aramid fiber in which a conductive substance is kneaded into the pile yarn. However, in this method, in order to obtain excellent conductivity, the content of the conductive fine particles has to be increased, and the problems of lowering the yarn-making property and yarn strength remain.
JP 2006-348439 A JP2004-2111247 JP2004-93948

  The present invention has been made in view of such a technical background, and performs conductive processing on the surface of a heat-resistant yarn so as not to impair the properties (for example, stretchability, strength, texture, etc.) of the yarn. An object of the present invention is to obtain a heat-resistant conductive yarn with little deterioration in conductive performance.

  As a result of intensive investigations to solve such problems, the present inventors have covered the surface of a yarn having heat resistance with a conductive polymer, so that the performance possessed by the yarn is not impaired, and heat resistance and conductivity are not impaired. The inventors have found that a yarn excellent in properties can be obtained and have reached the present invention. In order to achieve the above object, the present invention provides the following means.

[1] A pretreatment step in which an aqueous treatment liquid containing a dopant, an oxidizing agent, a crosslinking agent, and a binder resin is attached to at least the surface of the yarn as a pretreatment, and the aqueous treatment liquid is attached to the heat-resistant yarn. A polymerization process for obtaining a conductive yarn in which at least a part of the surface of the yarn is coated with polypyrrole by bringing the obtained yarn into contact with a pyrrole monomer in a gas phase state, and as a post-treatment, a dopant, an oxidizing agent, a crosslinking agent and a binder A method for producing a heat-resistant conductive yarn, comprising a post-treatment step in which an aqueous treatment liquid containing a resin is attached to at least the surface of the yarn subjected to the polymerization step.

[2] In the aqueous treatment liquid, the dopant content is 0.1 to 10% by mass, the oxidant content is 0.1 to 10% by mass, the crosslinking agent content is 0.1 to 10% by mass, 2. The method for producing a heat-resistant conductive yarn according to item 1, wherein the content of the binder resin is 0.01 to 2.0% by mass.

[3] In the pretreatment step, by applying the aqueous treatment liquid on at least the surface of the yarn using a roll coater, the solid content of the aqueous treatment liquid is 0.2 to 20 parts by mass with respect to 100 parts by mass of the yarn. 3. The method for producing a heat-resistant conductive yarn according to item 1 or 2, wherein the heat-resistant conductive yarn is adhered.

[4] In the polymerization step, the polypyrrole is adhered at a ratio of 0.2 to 5 parts by mass with respect to 100 parts by mass of the yarn by bringing the yarn attached with the aqueous treatment liquid into contact with a pyrrole monomer in a gas phase. 4. The method for producing a heat-resistant conductive yarn according to any one of items 1 to 3, wherein:

[5] In the post-treatment step, the aqueous treatment liquid is applied to at least the surface of the yarn using a roll coater, so that the solid content of the aqueous treatment solution is 0.2 to 20 parts by mass with respect to 100 parts by mass of the yarn. 5. The method for producing a heat-resistant conductive yarn according to any one of items 1 to 4, which is adhered.

[6] The heat resistance according to any one of items 1 to 5, wherein an aromatic sulfonic acid is used as the dopant, a persulfate is used as the oxidizing agent, and a melamine resin is used as the crosslinking agent. For producing conductive conductive yarn.

[7] A heat-resistant conductive yarn produced by the production method according to any one of items 1 to 6, wherein the surface resistivity is less than 1 × 10 ⁸ Ω / □.

In the invention of [1], an aqueous treatment liquid containing a dopant, an oxidizing agent, a cross-linking agent and a binder resin is attached to at least the surface of the yarn as a pretreatment to the yarn having heat resistance. By bringing into contact with the pyrrole monomer in the phase state, the pyrrole monomer is polymerized, and at least a part of the surface of the heat-resistant yarn is coated with polypyrrole to form a conductive film, and conductivity is imparted. Furthermore, since an aqueous treatment liquid containing a dopant, an oxidizing agent, a crosslinking agent, and a binder resin is attached to at least the surface of the yarn coated with the polypyrrole, polymerization of unreacted pyrrole monomer proceeds, and the binder resin A polypyrrole film is firmly fixed to the surface of the yarn, and a method for producing a yarn having both heat resistance and conductivity in which the polypyrrole is prevented from falling off can be obtained.

In the invention [2], the content of the dopant in the aqueous treatment liquid is 0.1 to 10% by mass, the content of the oxidizing agent is 0.1 to 10% by mass, and the content of the crosslinking agent is 0.1 to 10%. 10% by mass and the binder resin content is 0.01 to 2.0% by mass, so that the pyrrole monomer undergoes oxidative polymerization on the surface of the heat-resistant yarn and can provide reliable conductivity. A film can be formed and a method for producing a yarn having both heat resistance and conductivity can be obtained.

In the invention of [3], in the pretreatment step, since the aqueous treatment liquid is applied to at least the surface of the yarn using a roll coater, the aqueous treatment liquid is applied in an appropriate amount without unevenness, and 100 parts by mass of the yarn The solid content of the aqueous treatment liquid is adhered to 0.2 to 20 parts by mass with respect to the surface of the yarn having heat resistance by polymerizing the pyrrole monomer by contacting with the pyrrole monomer in the vapor phase in the next step. Is coated with polypyrrole to form a conductive film, and a conductive film that provides reliable conductive performance can be formed, whereby a method for producing a yarn having both heat resistance and conductivity can be obtained.

In the invention of [4], in the polymerization step, 0.2 to 5 parts by mass of polypyrrole is added to 100 parts by mass of the yarn by bringing the yarn to which the aqueous treatment liquid has adhered into contact with a pyrrole monomer in a gas phase. Since it adheres at a ratio, it is possible to form a conductive film that provides reliable conductive performance, and to produce a yarn having both heat resistance and conductivity.

In the invention of [5], in the post-treatment step, the aqueous treatment liquid is applied onto at least the surface of the yarn using a roll coater, so that the aqueous treatment liquid is applied in an appropriate amount without unevenness, and is applied to 100 parts by mass of the yarn. On the other hand, since 0.2 to 20 parts by mass of solid content of the aqueous treatment liquid can be adhered, the polymerization of unreacted pyrrole monomer proceeds, and the polypyrrole film is firmly fixed to the surface of the yarn by the binder resin, and the polypyrrole falls off. It can be set as the manufacturing method of the thread | yarn which has heat resistance and electroconductivity which prevented this.

In the invention of [6], aromatic sulfonic acid is used as the dopant, persulfate is used as the oxidizing agent, and melamine resin is used as the cross-linking agent. It is possible to form a conductive film that provides a good conductive performance and to produce a yarn having both heat resistance and conductivity.

In the invention of [7], since it is a heat-resistant conductive yarn manufactured by the manufacturing method according to any one of items 1 to 6, the surface resistivity is less than 1 × 10 ⁸ Ω / □, It can be set as the heat resistant electrically conductive thread which has electroconductivity.

  The heat-resistant yarn in the present invention may be a conventionally known heat-resistant yarn. For example, an aramid fiber yarn, a polyphenylene sulfide yarn, etc. can be illustrated. Aramid fibers are made of aromatic polyamide and are known as engineering plastics with high heat resistance and high strength. Polyphenylene sulfide resin is a thermoplastic crystalline plastic that has a heat distortion temperature of 260 ° C. or higher and most acid. -Resin with excellent chemical resistance that is not affected by alkali or organic solvent.

  As the aqueous treatment liquid, an aqueous emulsion liquid formed by dissolving a dopant, an oxidizing agent, and a crosslinking agent in water and forming an emulsion with water in which a binder resin is a dispersion medium is preferably used.

  The dopant is a substance for improving the conductivity of polypyrrole, and is not particularly limited. For example, the dopant is an aromatic sulfonic acid such as paratoluenesulfonic acid, benzenesulfonic acid, naphthalenesulfonic acid, dodecylbenzenesulfonic acid, and sulfonated polystyrene. Etc.

  The oxidizing agent is a substance for oxidative polymerization of a pyrrole monomer and is not particularly limited. For example, ammonium persulfate, iron chloride (trivalent), iron sulfate (trivalent), hydrogen peroxide, ammonium perborate, chloride Copper (divalent) etc. are mentioned. Also, a ferric salt of sulfonic acid used as a dopant (for example, a ferric salt of paratoluenesulfonic acid) can be used as an oxidizing agent.

  The crosslinking agent is a substance for linking polymers, and is not particularly limited. Examples thereof include methylated melamine resin, methylated urea resin, epoxy resin, NN′-methylenebisacrylamide, and ethylene glycol dimethacrylate. Can be mentioned.

  The binder resin is not particularly limited. For example, vinyl resins typified by homopolymers or copolymers such as vinyl chloride, vinyl acetate, vinylidene chloride, acrylic resins, polyester resins, fluororesins, or these resins Examples thereof include modified resins.

  In the aqueous treatment liquid, the content of the dopant is 0.1 to 10% by mass, the content of the oxidizing agent is 0.1 to 10% by mass, the content of the crosslinking agent is 0.1 to 10% by mass, The content is preferably set to 0.01 to 2.0% by mass. By setting the content in such a range, the production efficiency of polypyrrole can be maintained high and the polypyrrole can be sufficiently adhered to the yarn in the subsequent polymerization step.

  The method for adhering the aqueous treatment liquid to at least the surface of the heat-resistant yarn is not particularly limited, and examples thereof include application by a roll coater or spray. Among them, by applying to at least the surface of the yarn using a roll coater, 0.2 to 20 parts by mass of the solid content (dopant, oxidizing agent and binder resin) of the treatment liquid is adhered to 100 parts by mass of the yarn. preferable. By using a roll coater, a smaller amount of solid content can be uniformly and selectively attached to the surface area of the yarn, so that sufficient conductivity and heat resistance can be obtained while ensuring the softness of the conductive yarn. be able to.

  Next, the pyrrole monomer in the gas phase is brought into contact with the yarn in which the aqueous treatment liquid is adhered to at least the surface of the heat-resistant yarn in this manner. (Polymerization step) As a result, the pyrrole monomer in the vapor phase comes into contact with the aqueous treatment liquid on the surface of the yarn and polymerizes, so that a conductive yarn having heat resistance, wherein at least a part of the surface of the yarn is coated with polypyrrole, Obtainable. For example, after putting the yarn with the aqueous treatment liquid attached into the reaction chamber, the reaction chamber is filled with vapor (gas) of pyrrole monomer, and in this state, the entire amount of the oxidant reacts and polymerizes for a predetermined time (for example, By allowing it to stand (until the reaction stops), pyrrole is vapor-phase polymerized to obtain a conductive yarn in which at least a part of the surface of the heat-resistant yarn is coated with polypyrrole.

  The boiling point of pyrrole monomer at atmospheric pressure is 130 ° C., but it vaporizes in air even at temperatures below 130 ° C. until reaching the saturated vapor pressure. Therefore, for example, an evaporator of liquid pyrrole is installed in the reaction chamber, vaporized pyrrole and liquid pyrrole are maintained in an equilibrium state, and a heat-resistant yarn with the aqueous treatment liquid attached to the equilibrium atmosphere is disposed. Alternatively, an evaporator containing liquid pyrrole may be installed outside the room and bubbled with an inert carrier gas such as nitrogen to supply vaporized pyrrole together with the inert carrier gas into the reaction chamber. Regardless of whether the evaporator is installed inside or outside the reaction chamber, the temperature of the liquid pyrrole in the evaporator is usually preferably set to 5 to 100 ° C, and more preferably set to 20 to 50 ° C. In this polymerization step, the gas phase polymerization reaction of pyrrole naturally stops as the oxidizing agent is consumed in the yarn to which the aqueous treatment liquid is attached.

In the polymerization step, polypyrrole is attached at a ratio of 0.2 to 5 parts by mass with respect to 100 parts by mass of the yarn by bringing the heat-resistant yarn attached with the aqueous treatment liquid into contact with a pyrrole monomer in a gas phase state. Preferably. When the content is 0.2 parts by mass or more, a heat-resistant conductive yarn excellent in conductivity having a surface resistivity of less than 1 × 10 ¹⁰ Ω / □ can be obtained. Sufficient softness can be secured. In particular, it is particularly preferable to attach polypyrrole at a ratio of 0.5 to 3 parts by mass with respect to 100 parts by mass of the yarn.

  The pyrrole monomer is not particularly limited. For example, pyrrole may be used alone, or pyrrole and a pyrrole derivative copolymerizable with the pyrrole (N-methylpyrrole, 3-methylpyrrole, One or more mixed monomers such as 3,5-dimethylpyrrole and 2,2′-bipyrrole) may be used. That is, the polypyrrole may be a pyrrole homopolymer or a copolymer of pyrrole and a pyrrole derivative.

  Next, the conductive yarn having heat resistance obtained through the polymerization step is further treated as an aqueous treatment liquid containing a dopant, an oxidizing agent, a crosslinking agent and a binder resin, and the heat resistance through the polymerization step is increased. It adheres to at least the surface of the thread it has. As a result, polymerization of unreacted pyrrole monomer proceeds, and the polypyrrole film is firmly fixed to the surface of the yarn by the binder resin, so that the yarn having both heat resistance and conductivity in which the polypyrrole is prevented from falling off can be obtained. .

  Furthermore, in the post-treatment step, the aqueous treatment liquid is applied to at least the surface of the yarn using a roll coater, so that the solid content of the aqueous treatment solution is 0.2 to 20 parts by mass with respect to 100 parts by mass of the yarn. Preferably. By using a roll coater, a smaller amount of solid content can be uniformly and selectively attached to the surface area of the yarn, so that sufficient electrical conductivity can be obtained while ensuring the softness of the yarn.

  Next, the conductive yarn having heat resistance obtained through the post-treatment step is dried, washed with water, etc. to remove remaining free dopants, and then subjected to a drying treatment, thereby providing heat resistance. And a thread having both electrical conductivity can be obtained.

  Next, specific examples of the present invention will be described, but the present invention is not particularly limited to these examples. In addition, the measurement method of friction fastness and surface resistance value was performed with the following method.

<Friction fastness> The friction fastness of the conductive yarn was evaluated in accordance with JIS L0949-2004 type 2 (gray scale determination). The larger the “Class” value of the fastness to friction, the better the friction resistance. Grade 3 or higher was accepted.

<Surface Resistance Value> The surface resistivity level of the conductive yarn was evaluated using a surface resistance measuring instrument (four probe method; JIS K7194). The meaning of each numerical value of the evaluation result is as follows.
“10 or more” ··· 1.0 × 10 ¹⁰ Ω / □ or more “9” ··· 1.0 × 10 ⁹ Ω / □ or more and less than 1.0 × 10 ¹⁰ Ω / □ 8 ”... 1.0 × 10 ⁸ Ω / □ or more and less than 1.0 × 10 ⁹ Ω / □“ 7 ”... 1.0 × 10 ⁷ Ω / □ or more 1.0 × 10 ⁸ Ω / □ or less “6” ··· 1.0 × 10 ⁶ Ω / □ or more 1.0 × 10 ⁷ Ω / □ or less “5” ··· 1.0 × 10 ⁵ Ω / □ or more and less than 1.0 × 10 ⁶ Ω / □ “4”... 1.0 × 10 ⁴ Ω / □ or more and less than 1.0 × 10 ⁵ Ω / □ “3”・ ・ ・ 1.0 × 10 ³ Ω / □ or more and less than 1.0 × 10 ⁴ Ω / □ “2” .... 1.0 × 10 ² Ω / □ or more 1.0 × 10 ³ Ω / □ Less than □ "1" ... 1.0 x 10 ¹ Ω / □ or more and less than 1.0 x 10 ² Ω / □

<Heat resistance test> The conductive yarn is allowed to stand in an oven at 180 ° C. for 24 hours, and the surface resistivity is measured to check whether there is a change in the level of surface resistivity. did.

<Thread softness (texture) evaluation method heat resistance test> Evaluation was made in the following three stages by the touch when the conductive yarn was touched by hand.
“◯”: Softness was felt.
“△”: A slight hardness was felt.
“×”: There was a feeling of hardness and the touch was not good.

<Example 1>
An aqueous treatment solution was applied to the surface of 167 dtex / 48f polyphenylene sulfide yarn (original yarn made by Toyobo Co., Ltd.) using a roll coater. (Pretreatment step) As the aqueous treatment liquid, 1% by mass of ammonium persulfate (oxidizing agent), 1% by mass of paratoluenesulfonic acid (dopant), 1% by mass of methylated melamine resin (crosslinking agent), polyester resin An aqueous solution containing 1% by mass of (binder resin) was used. In this aqueous treatment solution, ammonium persulfate, paratoluenesulfonic acid, and methylated melamine resin are dissolved in water, while polyester resin is a dispersoid and forms an emulsion with water as a dispersion medium. Since 10 parts by mass of the aqueous treatment liquid per 100 parts by mass of the polyphenylene sulfide yarn (original) was applied by the roll coater, the solid content of the aqueous treatment liquid per 100 parts by mass of the polyphenylene sulfide yarn (original) ( The adhesion amount of ammonium persulfate, paratoluenesulfonic acid, methylated melamine resin, polyester resin) was 0.3 part by mass.

  Next, the polyphenylene sulfide yarn to which the treatment liquid is adhered is squeezed into the reaction chamber with mangle and then filled with pyrrole vapor (gas) in the reaction chamber, and left in this state for 10 minutes to perform vapor phase polymerization of pyrrole. Polypyrrole was coated on at least a part of the surface of the polyphenylene sulfide multifilament yarn. (Polymerization step) After that, the polyphenylene sulfide yarn with attached polypyrrole is taken out of the reaction chamber, and the aqueous treatment solution is again applied by a roll coater to 10 parts by mass of the aqueous treatment solution per 100 parts by mass of the polyphenylene sulfide yarn (original). Adhesion (post-treatment step), polymerization of unreacted pyrrole monomer proceeded, dried at 120 ° C. for 5 minutes, washed with water to remove remaining free dopants, and further dried (at 120 ° C. for 5 minutes) As a result, a heat-resistant conductive yarn was obtained.

  Next, the surface resistance value, friction fastness, and heat resistance of this heat resistant conductive yarn were measured and listed in Table 1. In all cases, satisfactory values were obtained, and conductive yarns resistant to friction and having heat resistance could be obtained.

<Example 2>
Example 1 except that 50 parts by mass of an aqueous treatment liquid per 100 parts by mass of polyphenylene sulfide yarn (original) was applied by a roll coater (attached to the pretreatment process and the posttreatment process). A heat-resistant conductive yarn was obtained.

<Example 3>
Example 1 except that 100 parts by mass of an aqueous treatment liquid per 100 parts by mass of polyphenylene sulfide yarn (original) was applied by application with a roll coater (only the pretreatment process and the posttreatment process were the same as in Example 1). Similarly, a heat-resistant conductive yarn was obtained.

<Example 4>
Except that 5 parts by mass of an aqueous treatment liquid per 100 parts by mass of polyphenylene sulfide yarn (original) was applied by a roll coater (attached to the pretreatment process and the posttreatment process), the same as in Example 1. A heat-resistant conductive yarn was obtained.

<Example 5>
Example 1 except that 150 parts by mass of an aqueous treatment liquid per 100 parts by mass of polyphenylene sulfide yarn (original) was applied by application with a roll coater (only the pretreatment process and the posttreatment process were the same as in Example 1). Similarly, a heat-resistant conductive yarn was obtained.

<Example 6>
As an aqueous treatment liquid (both pre-treatment and post-treatment), ammonium persulfate (oxidant) is 2% by mass, paratoluenesulfonic acid (dopant) is 2% by mass, and methylated melamine resin (crosslinking agent) is 2% by mass. A heat-resistant conductive yarn was obtained in the same manner as in Example 1 except that an aqueous solution containing 2% by mass of a polyester resin (binder resin) was used.

<Comparative Example 1>
In Example 1, as an aqueous treatment liquid (both pre-treatment and post-treatment), 1% by mass of ammonium persulfate (oxidizing agent), 1% by mass of para-toluenesulfonic acid (dopant), methylated melamine resin (crosslinking agent) ) With an aqueous solution containing 1% by mass, dipped in an aqueous emulsion containing 1% by mass of a polyester resin (binder resin) after the post-treatment step, drained and dried at 130 ° C. for 15 minutes. Except for the above, a heat-resistant conductive yarn was obtained in the same manner as in Example 1.

<Comparative Example 2>
In Example 1, a heat resistant conductive yarn was obtained in the same manner as in Example 1 except that ammonium persulfate (oxidant) in the aqueous treatment liquid was set to 0.

<Comparative Example 3>
In Example 1, a heat-resistant conductive yarn was obtained in the same manner as in Example 1 except that the paratoluenesulfonic acid (dopant) of the aqueous treatment liquid was changed to 0.

<Comparative example 4>
In Example 1, a heat-resistant conductive yarn was obtained in the same manner as in Example 1 except that the methylated melamine resin (crosslinking agent) in the aqueous treatment liquid was changed to 0.

<Comparative Example 5>
A conductive yarn was obtained in the same manner as in Example 1 except that the polyester yarn was used as the polyphenylene sulfide yarn in Example 1.

  As is apparent from the table, the heat-resistant conductive yarns of Examples 1 to 6 manufactured by the manufacturing method of the present invention have low surface low efficiency, excellent conductivity, high heat resistance, and friction fastness. The degree was also good and had sufficient durability. In addition, as shown in Comparative Examples 1 to 4, the heat-resistant conductive yarn manufactured with the treatment liquid lacking any one of the oxidizing agent, the dopant, the crosslinking agent, and the binder resin in the aqueous treatment liquid has sufficient conductivity. It was not equipped with friction fastness. Moreover, in Comparative Example 5 processed into a polyester yarn, a heat-resistant conductive yarn was not obtained.

Claims (7)

  A pretreatment step for attaching an aqueous treatment liquid containing a dopant, an oxidizing agent, a cross-linking agent and a binder resin to at least the surface of the yarn as a pretreatment on the yarn having heat resistance, and a yarn to which the aqueous treatment liquid is adhered Contains a polymerization process for obtaining a conductive yarn in which at least a part of the surface of the yarn is coated with polypyrrole by contacting with a pyrrole monomer in a gas phase state, and a dopant, an oxidizing agent, a cross-linking agent, and a binder resin as a post-treatment. A method for producing a heat-resistant conductive yarn, comprising a post-treatment step in which an aqueous treatment liquid is attached to at least the surface of the yarn that has undergone the polymerization step.   In the aqueous treatment liquid, the content of the dopant is 0.1 to 10% by mass, the content of the oxidizing agent is 0.1 to 10% by mass, the content of the crosslinking agent is 0.1 to 10% by mass, Content rate is 0.01-2.0 mass%, The manufacturing method of the heat resistant electrically conductive yarn of Claim 1 characterized by the above-mentioned. In the pretreatment step, by applying the aqueous treatment liquid to at least the surface of the yarn using a roll coater, 0.2 to 20 parts by mass of the solid content of the aqueous treatment liquid is adhered to 100 parts by mass of the yarn. The method for producing a heat-resistant conductive yarn according to claim 1 or 2, wherein:
  In the polymerization step, polypyrrole is adhered at a ratio of 0.2 to 5 parts by mass with respect to 100 parts by mass of the yarn by bringing the yarn to which the aqueous treatment liquid is adhered into contact with a pyrrole monomer in a gas phase. The method for producing a heat-resistant conductive yarn according to any one of claims 1 to 3.   In the post-treatment step, by applying the aqueous treatment liquid on at least the surface of the yarn using a roll coater, 0.2 to 20 parts by mass of the solid content of the aqueous treatment liquid is adhered to 100 parts by mass of the yarn. The method for producing a heat-resistant conductive yarn according to any one of claims 1 to 4, wherein:   The heat-resistant conductive material according to any one of claims 1 to 5, wherein an aromatic sulfonic acid is used as the dopant, a persulfate is used as the oxidizing agent, and a melamine resin is used as the crosslinking agent. Yarn manufacturing method. A heat resistant conductive yarn produced by the production method according to claim 1, wherein the surface resistivity is less than 1 × 10 ⁸ Ω / □.