GB452006A - A process of dyeing - Google Patents

Abstract

Substantive dyes, dyeing with; regenerated celluloses, dyeing.--Cellulosic material is dyed directly with an alkali salt of a sulphonic acid of a diarylfluorindine of the general formula <FORM:0452006/IV/1> (R representing aryl radicles which may be the same as or different from those otherwise present) which contains either negative groups or (as the R's or as the aryl groups) polynuclear ring systems or both, and which may be halogenated. Specified negative groups are nitro, CO-alkyl, CO-aryl, carboxyl and quinone groups and specified ring systems are those of naphthalene, diphenyl, stilbene, pyrene and anthracene. The dyestuffs are obtainable as described in Specification 442,732. The following examples are specified: (1) To a melt of p-aminodiphenyl (10 parts) at 90 DEG C. are added slowly, with stirring, p-aminodiphenyl hydrochloride (1 part) and p-nitrosophenol (1 part) and the whole is cooled to 70 DEG C. and alcohol is added to precipitate crystals which are filtered and washed; these are dissolved in nitrobenzene, the solution is boiled for \ba1/2\be hour with an addition of lead dioxide and the fluorindine which separates on cooling is sulphonated; cotton is dyed a clear blue by treatment for 1 hour in an aqueous solution at 85--90 DEG C. containing the dyestuff product, sodium chloride and an alkylnaphthalenesulphonate obtainable as described in Specification 246,817, [Class 2 (iii)]; (2) The fluorindine obtained from 3 - aminopyrene and p - quinonedianil, as described in example 3 of Specification 442,732, is sulphonated; cotton yarn is dyed green, fast to light by treatment for 1 hour in an aqueous solution at 90--95 DEG C. containing the dyestuff product, sodium chloride and sodium carbonate; (3) Viscose yarn is similarly dyed with the dyestuff of (2) in an aqueous solution at 85--90 DEG C. containing sodium sulphate and Marseilles soap; (4) Mercerized cotton fabric is dyed grey by treatment for 1 hour in an aqueous solution at 85--90 DEG C. containing a dyestuff obtained as in (2) but with stronger sulphonation, sodium chloride and sodium carbonate. The Specification as open to inspection under Sect. 91 comprises also the use of alkali salts of sulphonic acids of fluorindine compounds in general. This subject-matter does not appear in the Specification as accepted.