Compounds of formula (I), where R1, R2, R3, R4 and R5 have defined meanings ##STR1## are useful as surfactants especially in agrochemical formulations, pigment dispersions and domestic detergent formulations. Compounds where one of R1 and R2 is hydrogen and the other is C8 to C18 straight chain alkenyl group, the group --NR3 R4 is the residue of a glycamine, especially a glucamine, and R5 is --NR3 R4 as defined (especially a glycamine residue) or a group O.(AO)n.R6 where AO is an alkylene oxide, especially an ethylene oxide, residue, n is especially from 3 to 50 and R6 is a C1 to C6 alkyl group, are particularly desirable.

This invention relates to surfactants and in particular to novel surfactants based on derivatives of substituted succinic acids and to the use of these surfactants particularly as adjuvants in agrochemical formulations and as dispersants and/or emulsifiers in agrochemical, as dispersants for pigments, especially in aqueous dispersions, as emulsifiers in emulsion polymerisation, as surfactants in domestic detergents, particularly heavy duty laundry liquids, especially non-aqueous heavy duty laundry liquids, and other applications.

In recent years there has been an increasing desire to replace well established surfactants with materials of increased biodegradability. There is, however, great practical difficulty in devising alternatives to substances of excellent performance which have maintained an important position in the market for several decades.

EP 0107199 B and published PCT Application No WO 94/00508 A describe surfactants based on alk(en)yl substituted succinic acid(cas:110-15-6) alkylene oxide esters and amides.