Fluorescent whitening agents

Abstract

The invention provides a fluorescent whitening agent or optical brightener of formula (I) or (II) having the structure: (I) (II), wherein Y is Z or X′L; wherein: A is CR1R2(CH2)n wherein R1 is H, CH2OH or COZ, R2 is H or CH2OH and wherein n is 1 or 2, or wherein A is an optionally substituted aromatic or heteroaromatic ring fused with N and X wherein N and X are respectively bound to adjacent carbon atoms on the ring; X is O, S or N—H; Y is Z or X′L; the or each Z is independently OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, wherein M is selected from an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alkyl alcohol polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester having from 2 to 1000 repeat units, or a polyoxyalkylene chain having from 2 to 1000 repeating units; q is 1 to 5; R4 is independently selected from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl or dicarbamoylmethyl; alternatively, NR42 represents a heterocyclic ring, e.g. morpholine; and wherein when Y is X′L; X′ is O, S or N—H; and L represents a linker moiety connecting m repeating units of formula I or II having X′ as defined above in place of Y; R is H, CHR5R6, R5, R6, an alkylsulphonate, a polyether, CH2COZ or CH(COZ)((CH)nCOZ) in which each Z may be the same or different, R5 and R6 independently represent hydrogen, alkyl (such as methyl, ethyl, propyl, isopropyl), vinyl, phenyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1,2-dihydroxyethyl, aminomethyl, (dimethylamino)methyl, 5-aminopentyl, or cyano, optionally wherein R5 and R6 are the same or different, and n is 1 or 2.

Dependencies are inferred from the claim text.