Nitrogen-substituted water-dispersible phthalocyanine dyes

A phthalocyanine dye of formula (I) is provided: wherein: M is a metal group or is absent; n is 1 or 2; X is selected from —CHR 3 —, —NR 3 —, —O— or —S—; R 1 , R 2 and R 3 are independently selected from hydrogen, C 1-8 alkyl, C 1-8 alkoxy, carboxy, carboxy-C 1-8 alkyl, hydroxyl, hydroxy-C 1-8 alkyl; or R 1 and R 2 , or R 2 and R 3 together are joined to form a C 4-12 aryl or C 3-12 heteroaryl group, optionally substituted with 1, 2, 3 or 4 substituent groups, the or each substituent group being independently selected from C 1-12 alkyl, C 1-12 alkoxy, phenyl-C 1-8 alkyl, phenyl-C 1-8 alkoxy, —(OCH 2 CH 2 ) d OR d , cyano, halogen, amino, hydroxyl, thiol, —SR v , —NR u R v , nitro, phenyl, phenoxy, —CO 2 R v , —C(O)R v , —OCOR v , —SO 2 R v , OSO 2 R v , —NHC(O)R v , —CONR u R v , —CONR u R v , sulfonic acid, sulfonic acid salt and sulfonamide; d is an integer from 2 to 5000; R d is H, C 1-8 alkyl or C(O)C 1-8 alkyl and R u and R v are independently selected from hydrogen, C 1-12 alkyl, phenyl or phenyl-C 1-8 alkyl.