Abstract: A method of printing in which a solid ink composition is melted and ejected from a small orifice in the form of small drops directed towards a substrate on which an image is to be formed, characterized in that the solid ink composition comprises either a solution or a dispersion of a dye or a finely divided pigment in a halogenated hydrocarbon having a melting point of at least 50.degree. C. ("Ink A"), or a colored condensation polymer obtained by reacting a polymerizable lactone or a hydroxyalkanoic acid with a dye containing at least one active hydrogen atom ("Ink B").

Abstract: A phthalocyanine compound of the formula:(R--X--).sub.m Pc (--Y--R.sup.1 --Z--).sub.n (--SO.sub.3 M).sub.p IwhereinPc is a phthalocyanine nucleus (Pc);eachR independently is a monovalent aromatic radical linked to a peripheral carbon atom of the Pc nucleus through X;X selected from S, Se and Te;m is 4 to 16;eachR.sup.1 independently is a divalent aromatic radical linked to two adjacent peripheral carbon atoms of the Pc nucleus through Y and Z;Y is selected from S, NT, Se and Te;Z is selected from S, Se, Te, NT and O;T is selected from H, alkyl and aryl;n is 0 to 7;M is H, a metal or optionally-substituted ammonium;andP is from 1 to 16.The compounds have a significant absorption band in the near infra red and depending on the number of sulphonic acids groups and the nature of the counter ion are soluble in aqueous and polar organic media.

Abstract: A phthalocyanine compound of the formula:(R--X--).sub.m Pc(--Y--R.sup.1 --Z--).sub.n (--SO.sub.3 M).sub.p IwhereinPc is a phthalocyanine nucleus (Pc);eachR independently is a monovalent aromatic radical linked to a peripheral carbon atom of the Pc nucleus through X;X selected from S, Se and Te;m is 4 to 16;eachR.sup.1 independently is a divalent aromatic radical linked to two adjacent peripheral carbon atoms of the Pc nucleus through Y and Z;Y is selected from S, NT, Se and Te;Z is selected from S, Se, Te, NT and O;T is selected from H, alkyl and aryl;n is 0 to 7;M is H, a metal or optionally-substituted ammonium;andP is from 1 to 16.The compounds have a significant absorption band in the near infra red and depending on the number of sulphonic acids groups and the nature of the counter ion are soluble in aqueous and polar organic media.