Composition comprising - a binder comprising at least one cocondensate based on an ω-glycidyloxyalkylalkoxysilane of the formula I X-Si x (OR 1) 3-x, in which X is a 2-(3,4-epoxycyclohexyl)ethyl, 1-glycidyloxymethyl, 2-glycidyloxyethyl, 3-glycidyloxypropyl or 3-glycidyloxyisobutyl group, R 1 and R 2 independently of one another are each a linear or branched alkyl group having 1 to 4 C atoms, and x is 0 or 1, and on at least one bis(alkoxysilylalkyl)amine of the general formula II (OR 1) 3 Si - A - Si (OR 1) 3, in which the groups R 1 are identical or different and R 1 is a linear or branched alkyl group having 1 to 4 C atoms and A is a bis-amino-functional group of the formula IIa - (CH 2) i -[NH(CH 2) f] g NH[(CH 2) f* NH] g* -(CH 2) i* - (IIa), in which i, i*, f, f*, g or g* are identical or different, with i and/or i* = 1, 2, 3 or 4, f and/or f* = 1 or 2, g and/or g* = 0 or 1, and also, optionally, on at least one further silicon compound from the group consisting of tetraalkoxysilane, alkylalkoxysilane, mercaptoalkylalkoxysilane, carboxyalkylalkoxysilane, aminoalkylalkoxysilane, ureidoalkylalkoxysilane, thiocyanatoalkylalkoxysilane and silica sols, - water, - alcohol in an amount of less than 3% by weight, based on the composition, - at least one addition from the group consisting of particulate metals and/or metal alloys, the addition from the group consisting of particulate metals and/or metal alloys being selected from the group consisting of zinc powders, zinc flakes, zinc dust, powders or flakes or dust of zinc alloys, zinc-bismuth alloys, and - optionally at least one additive, the pH in the composition being 1 to 14 and the dry residue of the binder being 1% to 50% by weight, based on the binder used. - a binder comprising at least one cocondensate based on an ω-glycidyloxyalkylalkoxysilane of the formula I X-Si x (OR 1) 3-x, in which X is a 2-(3,4-epoxycyclohexyl)ethyl, 1-glycidyloxymethyl, 2-glycidyloxyethyl, 3-glycidyloxypropyl or 3-glycidyloxyisobutyl group, R 1 and R 2 independently of one another are each a linear or branched alkyl group having 1 to 4 C atoms, and x is 0 or 1, and on at least one bis(alkoxysilylalkyl)amine of the general formula II (OR 1) 3 Si - A - Si (OR 1) 3, in which the groups R 1 are identical or different and R 1 is a linear or branched alkyl group having 1 to 4 C atoms and A is a bis-amino-functional group of the formula IIa - (CH 2) i -[NH(CH 2) f] g NH[(CH 2) f* NH] g* -(CH 2) i* - (IIa), in which i, i*, f, f*, g or g* are identical or different, with i and/or i* = 1, 2, 3 or 4, f and/or f* = 1 or 2, g and/or g* = 0 or 1, and also, optionally, on at least one further silicon compound from the group consisting of tetraalkoxysilane, alkylalkoxysilane, mercaptoalkylalkoxysilane, carboxyalkylalkoxysilane, aminoalkylalkoxysilane, ureidoalkylalkoxysilane, thiocyanatoalkylalkoxysilane and silica sols, - water, - alcohol in an amount of less than 3% by weight, based on the composition, - at least one addition from the group consisting of particulate metals and/or metal alloys, the addition from the group consisting of particulate metals and/or metal alloys being selected from the group consisting of zinc powders, zinc flakes, zinc dust, powders or flakes or dust of zinc alloys, zinc-bismuth alloys, and - optionally at least one additive,