ФЛУОРЕСЦЕНТНЫЕ ОТБЕЛИВАЮЩИЕ ПИГМЕНТЫ

摘要

A whitening pigment comprising the reaction product of (a) a melamine-formaldehyde and/or a melamine-urea poly-condensation product and (b) a water-soluble fluorescent whitening agent of the formula (1), wherein each of the two R₁ groups, independent of the other, represents a C₁-C₆alkyl or C₁-C₄alkyl-O-C₁-C₄alkyl residue, which is substituted by one or two -CONH₂, -CONHC₁-C₄alkyl, -COOH, -SO₂NH₂, -SO₂NHC₁-C₄alkyl or -NH₂ groups, each of the two R₂ groups, independent of the other, represents hydrogen, C₁-C₄alkyl, C₂-C₄hydroxyalkyl or C₁-C₄alkoxyC₁-C₄alkyl, or R₁ and R₂ together with the nitrogen atom complete a piperazine ring, each of the two X₁ groups, independently, represent -OH, -OC₁-C₄alkyl, -Oaryl or the group -NR₃R₄, wherein R₃ and R₄ each, independently, represent hydrogen, C₁-C₄alkyl, C₂-C₄hydroxyalky, C₁-C₄alkoxyC₁-C₄alkyl, a phenyl, phenyl mono- or disulphonic acid residue or, R₃ and R₄, together with the nitrogen atom to which they are attached, complete a morpholino, piperidino or pyrrolidino ring or, alternatively, X₁ represents an amino acid residue from which a hydrogen atom has been abstracted from the amino group and M is hydrogen, an alkaline or alkaline earth metal ion, ammonium, mono- di-, tri- or tetra-substituted C₁-C₄alkylammonium or C₂-C₄hydroxyalkylammonium or mixtures thereof, a process for preparation of the pigments and the use thereof for the fluorescent whitening of paper.