Pressure-sensitive recording or copying material

Claim 1

In a pressure sensitive recording or copying material which contains, in its color reactant system; a color-producing acceptor as the developer for the color-forming agent, the improvement wherein the developer contains at least one member which is the reaction product of an electronegatively substituted aldehyde and an aliphatic organic compound containing hydroxyl groups, such that the aldehyde moiety is bonded to the radical of said aliphatic organic compound via at least one oxygen atom, said electronegatively substituted aldehyde being an electronegatively substituted mono- or polyaldehyde, wherein at least one such electronegative substituents is halo or cyano and interacts electromerically with at least one aldehyde group thereof, said aldehyde having the formula ##STR14## wherein R is a substituted or unsubstituted, saturated or unsaturated aliphatic radical, M is a substituted or unsubstituted aromatic, aromatic-cycloaliphatic, aromatic-heterocyclic or heterocyclic radical with aromatic properties, Y is halo or cyano, Z is hydrogen or an acid group, m and n are independently an integer of 1 to 6. Y 1 is hydrogen or halogen, Y 2 is halogen, and R 1 is hydrogen, carboxyl, alkyl of 1 to 3 carbon atoms, halogenoalkyl of 1 to 3 carbon atoms, phenyl, benzyl or halogenobenzyl.