In this study, two novel phthalonitrile derivatives were firstly prepared starting from 4‐nitrophthalonitrile: substitution of the nitro group with 3‐mercaptopropionic acid and 4‐mercaptobenzoic acid gave two precursors, namely, 4‐(carboxyethylsulphanyl)
phthalonitrile and 4‐(carboxyphenylsulphanyl)phthalonitrile. Zinc(ii), copper(ii) and cobalt(ii) metallophthalocyanines bearing four carboxylic acid groups on the periphery were prepared by cyclotetramerisation of the new
precursors in the presence of the corresponding divalent metal salts. The new compounds were characterised by elemental analyses, infrared, ultraviolet–visible, mass and proton nuclear magnetic resonance techniques. All these newly synthesised water‐soluble metallophthalocyanine
derivatives were supported on cationic cotton fabrics in the presence of ammonia solution and sodium hydroxide and the dyeing effectiveness, levelness and fastness of these novel dyed fabrics were investigated. These novel dyed fabrics are considered to be useful in the textile industry and
also in optical and catalytic applications, especially for air‐purifying materials in air conditioners.