To provide a method for producing an efficient and a high performance polyvinyl alcohol (PVA)-based flame retardant fiber capable of keeping flame retarding effects for a long time and further obtain the fiber and fiber structure obtained by the aforesaid method.
This method for producing a polyvinyl alcohol-based flame retardant fiber is to wet spin or dry spin a dope containing at least a vinyl alcohol-based polymer and an organic solvent into a solidification solution having a solidifying function to the vinyl alcohol-based polymer, subsequently pass the spun filaments at least an extracting process in which the spun filaments are impregnated in an extracting solution for extracting the organic solution constituting the spinning solution and a drying process to obtain the polyvinyl alcohol-based flame retardant polymer. In the method, the extracting solution is an organic solvent-based extracting solution and the fiber is produced by introducing a substituting process in which a substituting solution obtained by dissolving a hardly water soluble flame retardant in the organic solvent is added to the filaments in either process from removal of the solidifying solution to the drying process to produce the fiber.
SATO MASAHIRO
OMORI AKIO
OKI HIROYUKI
