Disclosed are oxalic acid diarylamides as ultraviolet absorbing agents for organic materials, the oxalic acid diarylamides being compounds of the formula A - NH - CO - CO - NH - A in which A represents a member selected from the group consisting of IN WHICH Z represents a member selected from the group consisting of a linear or branched alkyl group with 1 to 18 carbon atoms, an acetyl, butyryl, lauroyl, octadecanoyl, benzoyl, para-tertiary butylbenzoyl or para-chlorobenzoyl group, a benzyl group, a carbalkoxyalkyl group with a total of up to 12 carbon atoms, an allyl group and a mono-halogenalkyl group with up to 8 carbon atoms; Z1 represents an alkyl or mono-halogenalkyl group containing 1 to 18 carbon atoms; R19 represents an alkyl group containing 1 to 12 carbon atoms, w is 1, 2 or 3; X represents a member selected from the group consisting of an alkyl group with up to 12 carbon atoms, a halogen atom, a phenyl and a cyclohexyl group; and Y1 and Y3 each stands for hydrogen, an alkyl or alkoxy group with 1 to 8 carbon atoms, or Y2 may also represent a phenyl group; W represents an alkyl group with 1 to 18 carbon atoms or a carbalkoxyalkyl group with 3 to 8 carbon atoms.