COMPLEX FORMERS FOR POLYVALENT METAL IONS

摘要

The present invention relates to compounds of the general formula COOHCOOH ¦¦ H-C---C- X -PO3H2 ¦¦ HH in which X represents the group COOHCOOHPO3H2 ¦¦¦ -C-(CH2)- or -C- or -C- ¦¦¦ HRR and wherein R is a hydrogen atom, an alkyl radical with 1 to 4 C-atoms or a phenyl radical. These compounds may be used for the preparation of complex compounds with polyvalent metal ions.