phosphate preferably 1 3 phosphate preferred new copolymers according to the invention are furthermore those in which r 10 and independently thereof r 11 denote hydrogen the co use of acrylamide as component e in the copolymers according to the invention represents a further improvement of the fluorine containing copolymers known from u s pat no 5 247 008 the new copolymers according to the invention can also impart oil and water repellent properties to other substrates for example textiles leather and mineral substrates the preparation of the copolymers employed for treatment of the papers according to the invention is carried out for example by polymerization of the monomers i ii iii and iva b or c together in solution solvents which can be employed are ethyl acetate butyl acetate acetone methyl ethyl ketone methyl isobutyl ketone ethanol isopropanol tert butanol and the like which are known in principle to the expert the copolymerization is preferably carried out in acetone the polymerization here can be carried out discontinuously or continuously for the discontinuous procedure the batch or feed process may be mentioned agents which form free radicals such as for example azo compounds or peroxide are employed as initiators for the polymerization examples which may be mentioned are 2 2 39 azo bis isobutyronitrile 2 2 39 azo bis methylbutyronitrile tert butyl perpivalate and tert amyl peroxy 2 ethylhexanoate chain transfer agents such as for example dodecylmercaptan can be employed for regulation of the molecular weight the polymerization temperature is 40 u00b0 to 100 u00b0 c preferably 50 u00b0 to 90 u00b0 c aqueous dispersions of these copolymers are prepared by adding water to the solution of the copolymers after their preparation and distilling off at least.