Coloration of linear polymers by co-polycondensation with pigments

Claim 1

Process for forming a colored linear polyamide which comprises effecting the polycondensation of a monomer or monomers of the polyamide in the presence of a pigment of the polycyclic dicarboximide series containing two primary amine functional groups, wherein the pigment has the formula: ##STR4## wherein R represents a tetravalent residue of a substituted or unsubstituted mono- or poly-cyclic aromatic hydrocarbon or the tetravalent residue of a substituted or unsubstituted perinone; n represents 0 or 1; R 2 represents a C 1 - C 10 aliphatic, phenyl or diphenyl radical; and Z represents a primary amine group; wherein said pigment is in an amount of from 1 part per 1000 to 2 parts per hundred parts by weight of said monomer or monomers; and wherein said monomer or monomers are selected from the group consisting of 11-amino-undecanoic acid, Σ-caprolactam, and p-phenylenediamine, decamethylenediamine or hexamethylenediamine together with terephthalic, isophthalic, adipic or sebacic acid.