Stabilization of pyrrolopyrrole pigment

PURPOSE: To obtain a light-stabilized pigment compsn. comprising a specified pyrrolopyrrole pigment and a specified proportion of a nitroxyl compd., excellent in light stability and weather resistance and useful for an automotive paint, etc. CONSTITUTION: The light-stabilized pigment compsn. comprises one or more pyrrolo[3,4-c]pyrrole pigments of formula I (where each of A and B is an arom. group; and D is O or S) and 1-100 wt.%, based on the pigments, of a nitroxyl compd. or its acid-addition salt, e.g. the compd. of formula II. COPYRIGHT: (C)1994,JPO