FIELD: production of strands including glass fiber whose threads are coated with heat-conducting inorganic particles used for reinforcement of composite materials, such as laminate printed circuit boards. SUBSTANCE: fiber strand includes at least one glass fiber coated with layer of dry residue of aqueous slashing compound including solid inorganic particles at heat conductivity equal to or exceeding 25 W/m-K at temperature of 300 K. Solid particles include at least one particle from group: boron nitride, zinc and magnesium oxides, zinc sulfide, molybdenum disulfide, graphite, molybdenum, palladium, etc. Aqueous slashing compound may additionally include polymer material consisting of thermosetting and thermoplastic materials, starches and their mixtures. Said strands ensure compatibility of fiber with polymer materials of matrix and enhanced scattering of heat when used for reinforcement. EFFECT: enhanced efficiency. 40 cl, 9 dwg, 16 tbl, 7 ex
