Curing agent suitable for curing epoxy resins, containing at least one amine having at least one amino group with formula, wherein R represents a hydrogen atom or an alkyl group containing 1 to 12 C atoms; and X represents a residue selected from the group consisting of wherein R 1 respectively represents a hydrogen atom or an alkyl or alkoxy group containing 1 to 12 C atoms; and wherein the amine having at least one amino group with formula represents either an amine with formula, wherein A represents an a-valent hydrocarbon residue with a molecular weight in the range of 28 to 5000 g/mol, optionally containing ether groups, amino groups, hydroxyl groups or mercapto groups; and a represents an integer from 1 to 3; or an adduct of an amine with formula with at least one compound containing at least one reactive group selected from the group consisting of epoxy, episulfide, aziridine, cyclocarbonate, isocyanate, isothiocyanate, acrylate, methacrylate and acrylamide groups; characterized in that A represents either an a-valent alkyl, cycloalkyl or arylalkyl residue containing 2 to 20 C atoms or an a-valent polyalkyleneamine residue containing 1 to 10 secondary amino groups or an a-valent polyoxyalkylene residue containing 1 to 7 ether groups, wherein these residues comprises one or two primary or secondary aliphatic amino groups. R represents a hydrogen atom or an alkyl group containing 1 to 12 C atoms; and X represents a residue selected from the group consisting of wherein R 1 respectively represents a hydrogen atom or an alkyl or alkoxy group containing 1 to 12 C atoms; and wherein the amine having at least one amino group with formula represents either an amine with formula, wherein A represents an a-valent hydrocarbon residue with a molecular weight in the range of 28 to 5000 g/mol, optionally containing ether groups, amino groups, hydroxyl groups or mercapto groups; and a represents an integer from 1 to 3; or an adduct of an amine with formula with at least one compound containing at least one reactive group selected from the group consisting of epoxy, episulfide, aziridine, cyclocarbonate, isocyanate, isothiocyanate, acrylate, methacrylate and acrylamide groups; characterized in that A represents either an a-valent alkyl, cycloalkyl or arylalkyl residue containing 2 to 20 C atoms or an a-valent polyalkyleneamine residue containing 1 to 10 secondary amino groups or an a-valent polyoxyalkylene residue containing 1 to 7 ether groups, wherein these residues comprises one or two primary or secondary aliphatic amino groups. wherein R 1 respectively represents a hydrogen atom or an alkyl or alkoxy group containing 1 to 12 C atoms; and wherein the amine having at least one amino group with formula represents either an amine with formula, wherein A represents an a-valent hydrocarbon residue with a molecular weight in the range of 28 to 5000 g/mol, optionally containing ether groups, amino groups, hydroxyl groups or mercapto groups; and a represents an integer from 1 to 3; or an adduct of an amine with formula with at least one compound containing at least one reactive group selected from the group consisting of epoxy, episulfide, aziridine, cyclocarbonate, isocyanate, isothiocyanate, acrylate, methacrylate and acrylamide groups; characterized in that A represents either an a-valent alkyl, cycloalkyl or arylalkyl residue containing 2 to 20 C atoms or an a-valent polyalkyleneamine residue containing 1 to 10 secondary amino groups or an a-valent polyoxyalkylene residue containing 1 to 7 ether groups, wherein these residues comprises one or two primary or secondary aliphatic amino groups. A represents an a-valent hydrocarbon residue with a molecular weight in the range of 28 to 5000 g/mol, optionally containing ether groups, amino groups, hydroxyl groups or mercapto groups; and a represents an integer from 1 to 3; or an adduct of an amine with formula with at least one compound containing at least one reactive group selected from the group consisting of epoxy, episulfide, aziridine, cyclocarbonate, isocyanate, isothiocyanate, acrylate, methacrylate and acrylamide groups; characterized in that A represents either an a-valent alkyl, cycloalkyl or arylalkyl residue containing 2 to 20 C atoms or an a-valent polyalkyleneamine residue containing 1 to 10 secondary amino groups or an a-valent polyoxyalkylene residue containing 1 to 7 ether groups, wherein these residues comprises one or two primary or secondary aliphatic amino groups.