Dispersing agents

A composition of matter consisting essentially of a finely divided dispersion of a solid pigment or dyestuff having a particle size of less than 25 microns in a liquid hydrocarbon or chlorinated hydrocarbon containing dissolved therein a dispersing agent of the formula

• Y -- CO -- B -- A -- R
• wherein B is selected from --NH--, --O--, and --NT.sub.1 --, wherein T.sub.1 is alkyl containing up to 20 carbon atoms and A is alkylene or .beta.-hydroxyalkylene containing from 2 to 6 carbon atoms, R is NT.sub.2 T.sub.3 or NH.sub.2 .sup.+T.sub.3 T.sub.4 W.sup.- wherein T.sub.2, T.sub.3 and T.sub.4 are each independently H or alkyl containing up to 20 carbon atoms and W.sup.- is the anion of an acid, and Y is the residue of a polyester chain containing between 2 and 10 monomeric units which together with the --CO-- group is derived from a hydroxycarboxylic acid of the formula
• HO -- X -- COOH
• wherein X is a divalent saturated or unsaturated aliphatic radical containing between 8 and 20 carbon atoms and in which there are at least 4 carbon atoms between the hydroxy and carboxylic acid groups or from a mixture of such a hydroxycarboxylic acid and a carboxylic acid which is free from hydroxy groups, said pigment or dyestuff being present in an amount of 5-70 percent by weight based on the total weight of the dispersion and said dispersing agent being present in an amount of 5-50 percent by weight based on the weight of said pigment or dyestuff.