A considerable setback of polyamide fibers, especially polycaproamidefibers (PCAFs), is their low light resistance. This leads to changes in their appearance and their physicomechanical parameters under ambient atmosphere conditions and as a result of the effect of sunlight. This setback could be compensated to a certain extent by the introduction of suitable light stabilizers in the fiber mass. Depending on its efficiency, each light stabilizer is added at a concentration of 0.2-5% with respect to the mass of the polymer. We have investigated two possibilities for introducing the light stabilizer into the fiber mass. In the first one, the composition was finished immediately after the fiber spinning, and in the second one, polycaproamide granules were processed with a solution of light stabilizers before their melting. (c) 2006 Wiley Periodicals, Inc.