Fireproofing process for lignocellulosic materials, fireproof lignocellulosic materials thus obtained and their uses

摘要

The subject of the present invention is a process for the fireproofing of a lignocellulosic material, characterized in that it comprises the following steps: - optionally steam explosion of the lignocellulosic material, - impregnation of the lignocellulosic material, optionally steam explosion , in or with an aqueous solution comprising from 0.5% to 10% phytic acid and from 1% to 30% urea, and preferably from 3% to 7% phytic acid and from 15% to 22 % urea, said percentages being expressed by mass relative to the total mass of the aqueous solution, - drying of the impregnated lignocellulosic material, until it has a humidity ranging from 5% to 20%, said percentages being expressed in mass relative to the total mass of the impregnated lignocellulosic material, - cooking of the impregnated and dried lignocellulosic material, the flame-retardant lignocellulosic material thus obtained comprising a phosphorus content originating from phytic acid ranging from 0.1% to 10 %, preferably ranging from 0.3% to 3%, said percentages being expressed by mass relative to the total mass of the flame-retardant lignocellulosic material. The invention also relates to the flame-retardant lignocellulosic material thus obtained and its use for the manufacture of: - flame-retardant composite materials based on plant fibers, - flexible flame-retardant woven or non-woven materials based on plant fibers, and in particular textiles, - fire-retardant materials based on wood fibers and / or wood particles, and in particular fire-retardant wood panels.