developed in the first development is developed in the presence of a color coupler to form color images, saidphosphonocarboxylic acid compound being represented by the general formula (I): ##STR4## wherein R.sub.1 is --COOM' or --PO(OM).sub.2 ;R.sub.2 is a hydrogen atom, an alkyl group containing 1 to 4 carbon atoms, --(CH.sub.2).sub.n COOM' or a phenyl group;R.sub.3 is a hydrogen atom or --COOM'