Patent GB-316231-A (GB)
Title: Improvements in the manufacture and production of chromiferous dyestuffs
IPC: C09B45/01
Filed: 1928-01-23
Abstract: 316,231. I. G. Farbenindustrie Akt.- Ges. Jan. 23, 1928. Addition to 269,522. Azo dyes, soluble chromium compounds of. - The chromium compounds of azo dyestuffs obtainable by the process of the parent Specification are produced in substance or on the fibre by (a) treating in substance chromable o-oxyazo dyestuffs with larger amounts of compounds of trivalent chromium than are used according to that Specification and under mild conditions of concentration, temperature, and duration of heating, or (b) treating such chromable dyestuffs in substance or in the dyebath with chromed ooxyazo dyestuffs of the same or different kinds containing more than the minimum amount of chromium, or (c) dyeing the fibre successively with such a chromed dyestuff and an unchromed chromable dyestuff. The following examples are specified. (1) A mixture of the dyestuff from the nitrated diazo compound of 1 : 2-aminonaphthol-4-sulphonic acid and #-naphthol with specified amounts of chromium hydroxide, formic acid and water is boiled for 2 hrs. under reflux; the product, which contains about 2 atoms of chromium to 3 mols. of dyestuff, gives very fast black dyeings on wool, whereas if the boiling is prolonged or the heating is effected under pressure at 120‹ C., reddish black dyeings of inferior fastness are obtained. (2) A mixture of the dyestuff 4-nitro-2-aminophenol-6-sulphonic acid # 1-phenyl-3-methyl-5-pyrazolone with specified amounts of chromium hydroxide, formic acid, and water is boiled for 2 hrs. under reflux; the product gives fast red dyeings on wool, whereas if the duration of boiling is 20 hrs. or the heating is effected under pressure at 120‹ C. the product, containing 1 atom of chromium to 1 mol. of dyestuff, gives an orange dyeing; if the coupling component is replaced by 1-(4<1>-nitro)phenyl-3- methyl-5-pyrazolone the product of a short chromium treatment is redder and of smaller chromium content than that of a long treatment. (3) A mixture of the dyestuff 4-nitro-2-aminophenol-6-sulphonic acid # #-naphthol with specified amounts of chromium formate and water is boiled for ¢ hr.; the product is identical with that obtained according to example (2) of the parent Specification. (4) A mixture of the dyestuff 4-nitro-2-aminophenol-6-sulphonic acid # 1-phenyl-3-methyl-5-pyrazolone with specified amounts of chromium sulphate, sulphuric acid, and water is boiled for 24 hrs.; the product is identical with that of example (2). (5) A mixture of the chromium compound of the dyestuff from the nitrated diazo compound of 1 : 2-aminonaphthol-4-sulphonic acid and #-naphthol, containing 1 atom of chromium to 1 mol. of dyestuff, with specified amounts of the same unchromed dyestuff, formic acid, and water is boiled for 15 hrs; the product gives on wool faster black dyeings than are obtained with the initial chromed dyestuff. (6) A mixture of the chromium compound of the dyestuff from the nitrated diazo compound of 1 : 2-aminonaphthol-4-sulphonic acid and #-naphthol, containing 1 atom of chromium to 1 mol. of dyestuff, with specified amounts of the unchromed dyestuff 4-nitro-2- aminophenol-6-sulphonic acid # 1Àphenyl-3- methyl-5-pyrazolone, formic acid, and water is boiled for 20 hrs; the product gives fast reddish black dyeings on wool. (7) The chromium compound of the dyestuff 4-nitro-2-aminophenol-6- sulphonic acid # #-naphthol, containing 1 atom of chromium to 1 mol. of dyestuff, is boiled for a long time under reflux or heated for 2 hrs. under pressure at 120‹ C. with an aqueous solution containing about an equal amount of the same unchromed dyestuff; the product is identical with that obtained according to example (2) of the parent Specification. (8) Wool is dyed a fast green by boiling for 2 hrs. in a dyebath containing the chromium compound of* the dyestuff metanilic acid # salicylic acid, having 1 atom of chromium to 1 mol. of dyestuff, the unchromed dyestuff 3 : 4 : 6-trichlor-2-aminophenol # 1 : 8-aminonaphthol-2 : 4-disulphonic acid, and sulphuric acid; in some cases the chromed and unchromed dyestuffs may be applied successively to the fibre in either order. (9) A mixture of the chromium compound cf the dyestuff 4-nitro-2-aminophenol-6-sulphonic acid # #-naphthol, containing 1 atom of chromium to 1 mol. of dyestuff, with specified amounts of the unchromed dyestuff 2-aminophenol-4-sulphonic acid # m-phenylenediamine and water and some formic acid is boiled for a short time and concentrated by evaporation; the produce gives on wool from a sulphuric acid bath uniform fast brown dyeings which are darker than those obtained with the initial chromed dyestuff; if the unchromed dyestuff is replaced by 4-ritro-2- aminophenol-6-suphonic acid # p-cresol, the product gives deep pure brown dyeings on wool. (10) A mixture of specified amounts of the chromium compound of the dyestuffs 4.chloro-2- aminophenol-6-sulphonic acid # 1-plenyl-3- methyl-5-pyrazolone and of the same unchromed dyestuff is treated as in (9) or is boiled in an alkaline solution; the product gives red dyeings with a bluer tinge than is obtained with the initial chromed dyestuff.