Patent ID: 7846374
Filing Date: 2010-12-07
Classification: D01D

Abstract:
1. A method for preparing a nanofiber web comprising feeding a polymer solution, which comprises at least one polymer dissolved in at least one flammable solvent to a spinning nozzle; discharging the polymer solution from the spinning nozzle, at a polymer solution discharge rate of from 0.1 to 5 mL/min-hole, into a blowing gas mixture, wherein the blowing gas exits a jet at a lower end of the spinning nozzle into a spinning region defined between the spinning nozzle and a collector, and contacts the polymer solution in the spinning region after it exits the spinning nozzle, to form polymer nanofibers, and wherein the blowing gas comprises one or more inert gases that do not support combustion; and collecting the polymer nanofibers on the collector under the spinning nozzle, wherein an applied high voltage differential is maintained between the spinneret and the collector; and wherein the concentrations of solvent vapor and oxygen at any point in the spinning region are such that the concentration of solvent vapor does not exceed the lower explosive limit of the solvent in the spinning region at that point.