| abstract |
A process for the mass coloration or whitening of linear polyesters, wherein the polyester to be colored is mixed, in the solid or fused state, with a preparation consisting substantially of a colorant or fluorescent brightener which is soluble or insoluble in the polyester, and of a polystyrene with a softening point above 100 DEG C, and the resultant mixture, provided it is not already in the form of a melt, is converted into the molten state and formed into shaped articles. Evenly and deeply colored polyesters are obtained. |