| abstract |
A fluorescent whitening agent comprising a mixture of compounds of formulae (Ia), (Ib) and (Ic), in which the -SO3R groups are in the meta and/or para position, and wherein R and M, independently of each other are H, Na, Li, K, Ca, Mg, ammonium, or ammonium that is mono-, di-, tri- or tetra-substituted by C1-C4alkyl, C1-C4-hydroxyalkyl or a mixture thereof, a process for its preparation and its use to brighten paper and especially textile materials. |