Conductive far-infrared heat-generating fiber and preparation method therefor

A method for preparing a conductive far-infrared heat-generating fiber, comprising the following steps:

• A) pretreating a substrate fiber, and then drying,
• wherein step A) is specifically performed by:
• placing a pretreatment liquid into a liquid tank, drawing out the substrate fiber from a fiber reel I, impregnating the substrate fiber across a guide eyelit into the pretreatment liquid using a guide roller, controlling the amount of the liquid applied on the substrate fiber using a milling roll or a slit, and then drying by a heating device and winding the substrate fiber around a fiber reel II,
• wherein the pretreatment liquid comprises 0.01 wt %-30 wt % of surfactant or oxidant in water or an organic solvent;
• wherein the surfactant is at least one of anionic surfactant, cationic surfactant and Gemini surfactant;
• and the oxidant is at least one of organic oxidant and inorganic oxidant;
• and
• B) impregnating the substrate fiber obtained in step A) into a liquid of a conductive material, and then drying,
• wherein step B) is specifically performed by:
• placing the liquid of the conductive material into a liquid tank, drawing out the substrate fiber wound around the fiber reel II, impregnating the substrate fiber across a guide eyelit into the liquid of a conductive material using a guide roller, controlling the liquid applied on the substrate fiber in an amount of 5 wt %-150 wt % based on untreated substrate fiber using a milling roll or a slit, and then drying by a heating device and winding the substrate fiber around a fiber reel III;
• wherein step B) is carried out at least once,
• to obtain a conductive far-infrared heat-generating fiber;
• wherein the method further comprises curing the dried fiber after drying in step B), or when step B) is carried out more than once, the method further comprises curing after step B) is repeated,
• wherein the curing temperature is 100-250° C., and the curing time is 30-3600 s;
• wherein the liquid of the conductive material is at least one of conductive carbon black paste, conductive graphene paste, conductive carbon nanotube paste, and conductive graphite paste;
• wherein the conductive material in the liquid of conductive material is at least one of graphite, conductive carbon black, carbon nanotube, and graphene;
• wherein the liquid of the conductive material further comprises 0.1 wt %-50 wt % of additive, wherein the additive is resin and curing agent, wherein the resin is at least one of epoxy resin, organic silicone resin, polyimide resin, phenolic resin, polyurethane resin, acrylic resin and unsaturated polyester resin, and the curing agent is at least one of aliphatic amines, aromatic amines, amidoamines, latent curing amines, urea, polythiols and polyisocyanates;
• wherein the electrical resistance of the conductive far-infrared heat-generating fiber reaches 10 ohms·m−1 to 2,000,000 ohms·m−1;
• and when the conductive far-infrared heat-generating fiber is woven into a fabric, the fabric would emit far infrared rays having an emission wavelength of 5 microns to 14 microns and generate heat when the two ends of the fabric were applied a voltage of 3 volts to 36 volts, in which the emission rate of the far infrared rays ranged from 0.8 to 0.95, and the temperature increased by 1.4° C. to 30° C.