A tetrakisazo compound represented by the following formula (1) in the free acid form: ##STR1## wherein Q.sub.1 and Q.sub.2 independently represent phenylene or naphthylene group which may be optionally substituted, R.sub.4, R.sub.5 and R.sub.6 independently represent a hydrogen atom, a halogen atom, a hydroxy group, a sulfonic acid group or an amino, alkyl, alkoxy, carbamoyl or sulfamoyl group which may be optionally substituted, m is 0 or 1 and n is 1 or 2, and an ink which comprises the tetrakisazo compound. The ink exhibit excellent properties for ink jet printing.

Herein is provided a trisazo compound represented by formula (I) in the free acid form: ##STR1## wherein Q.sub.1 is an unsubstituted or substituted phenylene or naphthylene group, Q.sub.2 is an unsubstituted or substituted phenyl or naphthyl group, Z is --SO.sub.2 CH.sub.2 CH.sub.2 OH or --SO.sub.2 CH.sub.2 CH.sub.2 SO.sub.3 H group, and L is 0 or 1. The trisazo compound provided herein is excellent in solubility and gives deep colored dyed product or image when used in dyeing or printing, so that it is useful as a dye and an ink. Herein are also provided a method for dyeing fiber materials, paper or leather by using said trisazo compound, and an ink containing said trisazo compound.

A trisazo compound represented by the following formula (1) in the free acid form: ##STR1## wherein Q' is phenylene group, Q.sup.2 is phenyl or naphtyl group, one of the A and B is a hydroxy group and the other is an amino group, K is 1 or 2, one of m and n is 1 and the other is 0, X and Y independently of one another are each --OR.sup.1, --SR.sup.2, --NR.sup.3 R.sup.4 or ##STR2## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently of one another are each a hydrogen atom, an alkyl, phenyl or naphthyl group; r is 1 or 2; and Z is --CH.sub.2 --, --O--, --SO.sub.2 -- or --NR.sup.5 -- wherein R.sup.5 is a hydrogen atom or C.sub.1 -C.sub.4 alkyl group; a method for dyeing fiber material, paper or leather by using the trisazo compound; and an ink which contains the trisazo compound and which is excellent in storage stability and can give a clear black printed image having excellent water resistance and light fastness.

A homogeneous fluorescent ink has been conceived that has particular use in devices such as inking components of postage meters. The inks are in the form of solutions, and contain a soluble fluorescent toner that is dissolved within a polar organic solvent. Additives can be used to modify the properties of the ink.

Black compounds of Formula (1) having enhanced solubility in polar organic liquids which are useful as ink colorants in conventional and hot melt ink-jet printing and automatic identification, as black colorants for toners and thermal wax transfer sheets and as charge control agents for electrophotographic toners; ##STR1## wherein R is H, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, aryl, C.sub.4-8 cycloalkyl, --CN, --NO.sub.2, halogen, --COOR.sup.1, --OH, --SH or --SO.sub.3 A; R.sup.1 is A, C.sub.1-4 -alkyl or aryl; R.sup.2 is --NH.sub.2, --OH or --SO.sub.3 A; R.sup.3 is --NH.sub.2 or --OH; R.sup.4 is --NH.sub.2, --OH, --SO.sub.3 A or H; and A is NQ.sub.4 in which at least one Q is a branched chain fatty C.sub.6-20 -aliphatic group.