Use of quaternary ether amines of the formula I ##STR1## in which R.sub.1 is a saturated or unsaturated alkyl radical of from 12 to 24 carbon atoms, X and Y stand for hydrogen or methyl, but do not both represent methyl at the same time, n is a number of from 1 to 5, R.sub.2 and R.sub.3 stand for alkyl of from 1 to 4 carbon atoms, and A is the methosulfate, chloride, or the dimetho- or triethophosphate anion, as processing agents in the preparation and processing of native and synthetic fibers.