A composite yarn for technical or industrial use, particularly suitable for textile webs, is uniformly coated with a polymer and exhibits improved fir behavior and improved resistance to sheath stripping. The yarn may be obtained by a process where a continuous yarn, obtained by spinning a large number of fibers, such as about 100 to 600 fibers made of an organic or inorganic material, of a suitable yarn diameter, such as between about 1 to 10 micrometers, is subjected to a process for mechanically opening the yarn by splaying, to uniformly spread out and separate the fibers, including inner layers of the fibers, without impairing functional properties of the yarn, simultaneously with or prior to coating of the fibers by a polymer material having a viscosity between 1000 and 10,000 mPa·s, and formed to have a circular cross-section and uniformly distributed fibers throughout the cross-section of the polymer material to limit desheathing of the yarn.