Hardener component for a multi-component epoxy resin composition for the chemical fastening of structural elements, comprising a benzoxazine-amine adduct which is selected from the group consisting of substances according to formula la, substances according to formula Ib or mixtures thereof, comprising the following structures: and R 1, R 2, R 3, R 4 and R 5 each being independently selected from H, alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, arylalkyl, heteroalkyl, alkoxy, hydroxyl, hydroxyalkyl, carboxyl, halo, haloalkyl, amino, aminoalkyl, alkylcarbonyloxy, arylcarbonyloxy, alkoxycarbonyl, alkylcarbonyl, alkylsulfonylamino, aminosulfonyl, sulfonic acid or alkylsulfonyl functional groups, and also from combinations of two or more of these functional groups, it being possible for the functional groups to each be unsubstituted or optionally substituted; R 6 and R 7 each independently denoting H or an amino, diamino or polyamino functional group selected from the group consisting of aliphatic, alicyclic, aromatic or araliphatic amine functional groups and also combinations of two or more of these functional groups, it being possible for the functional groups to each be unsubstituted or optionally substituted; Z being selected from a direct bond, -C -, -S-, -O-, -S -, -S 2 -, -C(R 8)(R 9)-, - [C(R 8)(R 9)] m -C(R 8)(R 9)-[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -C(R 8)(aryl)-[C(R 10)(R 11)] n -, - [C(R 8)(R 9)] m -C -[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -S-[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -O-[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -S -[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -S 2 -[C(R 10)(R 11)] n -, a divalent heterocycle and -[C(R 8)(R 9)] m -arylene-[C(R 10)(R 11)] n -, m and n each being, independently of one another, between 0 and 10, preferably between 0 and 5, and R 8, R 9, R 10 and R 11 each independently having the same meaning as the functional groups R 1 to R 5; and an amine selected from the group consisting of aliphatic, alicyclic, aromatic and araliphatic amines and having an average of at least two reactive hydrogen atoms bonded to a nitrogen atom per molecule; characterized in that the benzoxazine-amine adduct is present in the hardener component in a proportion of from 8.5 wt.% to 75 wt.%. R 1, R 2, R 3, R 4 and R 5 each being independently selected from H, alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, arylalkyl, heteroalkyl, alkoxy, hydroxyl, hydroxyalkyl, carboxyl, halo, haloalkyl, amino, aminoalkyl, alkylcarbonyloxy, arylcarbonyloxy, alkoxycarbonyl, alkylcarbonyl, alkylsulfonylamino, aminosulfonyl, sulfonic acid or alkylsulfonyl functional groups, and also from combinations of two or more of these functional groups, it being possible for the functional groups to each be unsubstituted or optionally substituted; R 6 and R 7 each independently denoting H or an amino, diamino or polyamino functional group selected from the group consisting of aliphatic, alicyclic, aromatic or araliphatic amine functional groups and also combinations of two or more of these functional groups, it being possible for the functional groups to each be unsubstituted or optionally substituted; Z being selected from a direct bond, -C -, -S-, -O-, -S -, -S 2 -, -C(R 8)(R 9)-, - [C(R 8)(R 9)] m -C(R 8)(R 9)-[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -C(R 8)(aryl)-[C(R 10)(R 11)] n -, - [C(R 8)(R 9)] m -C -[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -S-[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -O-[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -S -[C(R 10)(R 11)] n -, -[C(R 8)(R 9)] m -S 2 -[C(R 10)(R 11)] n -, a divalent heterocycle and -[C(R 8)(R 9)] m -arylene-[C(R 10)(R 11)] n -, m and n each being, independently of one another, between 0 and 10, preferably between 0 and 5, and R 8, R 9, R 10 and R 11 each independently having the same meaning as the functional groups R 1 to R 5; and an amine selected from the group consisting of aliphatic, alicyclic, aromatic and araliphatic amines and having an average of at least two reactive hydrogen atoms bonded to a nitrogen atom per molecule; characterized in that the benzoxazine-amine adduct is present in the hardener component in a proportion of from 8.5 wt.% to 75 wt.%.