Boron chelate complexes of the general formula are described, where X is either —C(R1R2)— or —C(R1R2)—C(═O)—, in which R1, R2 independently of one another denote H, alkyl (with 1 to 5 C atoms), aryl, silyl or a polymer, and one of the alkyl radicals R1 or R2 may be bonded to a further chelatoborate radical, or X denotes 1,2-aryl with up to two substituents S in the positions 3 to 6 in which S1, S2 independently of one another denote alkyl (with 1 to 5 C atoms), fluorine or a polymer, as well as M+ denotes Li+, Na+, K+, Rb+, Cs+ or [(R3R4R5R6)N]+ or H+, where R3, R4, R5, R6 independently of one another denote H or alkyl with preferably 1 to 4 C atoms.