HOE 91/F 328 of the disclosure: Biodegradable spin finishes The invention relates to spin finishes which contain compounds of the formula HO(CH2CH20)x-RO-(CH2CH2O)yH I in which R is an alkylene radical which is mono- or polysubstituted by alkyl, has 2 to 4 carbon atoms in the alkylene chain and contains methyl, ethyl, propyl or isopropyl as the alkyl substituent, and the sum of x and y is 10 to 20, x and y being different from zero, and to a process for the spin finishing of fibers.