NEW REINFORCING MATERIALS BASED ON S- AND Z-TWISTED YARNS FOR THE MANUFACTURE OF COMPOSITE PARTS, METHODS AND USE
The reinforcing material comprises a unidirectional reinforcing ply (2) formed of one or more carbon yarns (3) and associated on one at least of its faces, preferably on each of its faces, with a porous polymeric layer (4, 5), where the polymeric part of the reinforcing material represents from 0.5% to 10% of its total mass and preferably from 2% to 6% of its total mass, characterized in that said carbon yarns (3) are individually twisted with a twist of 3 to 15 turns/m, preferably from 6 to 12 turns/m, and comprise at least one S-twist yarn and at least one Z-twist yarn, according to a selection in accordance with claim 1.