A new method has ben developed for applying the microcapsules in the spirming process, in aJJ those yaros made in ring spinning machines, wether short fibre or long fibre. The microcapsules were placed in the interstices of the yarn, before being communicated twist. Ihis allows solving the problem of permanencc of the effect provided by the active ingredients contained in the microcapsule, for functionality and use of textile garments, against repeated washing. The method is technical and industrial feasible. This has been demonstrated by the interest shown by an important manufacturer of textil e machinery for spinning. Ihe proposed method is valid fol' all types of fibres that are processed by the systems of carded corton, worsted, semí-worsted and woollen, when obtained in ring spinning machines. Ihe new method of application is suitable for alJ types of microcapsules, wich are curren tIy developed for use on textiles.