Patent GB-301754-A (GB)
Title: Process for dyeing viscose silk
IPC: C09B31/02
Filed: 1928-12-03
Abstract: 301,754. I. G. Farbenindustrie Akt.- Ges. Dec. 2, 1927, [Convention date]. Right to Patent relinquished. Azo dyes.-Uniform dyeings are obtained on viscose silk by the application of secondary disazo dyestuffs of the type A # M # E in which A is a primary aromatic monamine free from nitro or salicylic groupings, M is any customary middle component, and E is a substituted or unsubstituted naphthol or naphthylamine coupling in o-position to the OH or NH2 group, N-substituted 2-amino-8-naphthol-sulphonic acids being excepted. The following examples are specified : -(1) Knitted viscose is dyed uniform powerful blue shades, fast to light, by treatment at 80‹ C. for 1 hr. in a bath containing the dyestuff 4- aminotoluene-3-sulphonic acid # 1-amino-2- ethoxynaphthalene-6-sulphonic acid # 1: 4- naphthol sulphonic acid, sodium sulphate, and soap; a similar violet dyeing is obtained by using the dyestuff aniline-2-sulphonic acid # 1- aminonaphthalene-6-sulphonic acid # 2 : 6- naphtholsulphonic acid. (2) Knitted viscose is similarly dyed uniform violet shades, fast to light. using the dyestuff 3-aminobenzoic acid # 2- aminoanisol # 2-methylaminonaphthalene-7- sulphonic acid with the addition to the bath of I per cent of isohutylnaphthalene-sulphonic acid (obtained by the condensation of isobutylalcohol and naphthalene in presence of sulphuric acid); a similar clear orange dyeing is obtained by using the dyestuff aniline-2 : 5-disulphonic acid # 1- (3'-amino)-phenyl-3-methyl-5-pyrazolone # 1- naphthol-3: 6-disulphonic acid. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the use of dyestuffs of the above type where A is any diazo component free from nitro or salicylic acid groupings and where E indicates the components specified, but N-substituted 2 : 8 : 6-acids being excepted. In examples, viscose is dyed with the dyestuffs 4- amino-4<1>-oxyazobenzene-3<1>-carboxylic acid # 1 : 3-naphtholsulphonic acid (bluish red); 4- aminoacetanilide-3-sulphonic acid # 1-amino-2- ethoxynaphthalene-6-sulpbonic acid # N- acetyl-1 : 8-aminonaphthol-4-sulphonic acid (bluish green), and a uniform pure blue with the known dyestuff obtained from the monoazo product 5- amino-4-chloro-2-oxalylaminoanisol # 1-naphthol-4: 8-disulphonic acid by saponifying, diazotizing, and coupling with 1 : 6-dioxynaphthalene- 3-sulphonic acid. A table is also given showing the shades of the dyeings obtained on knitted viscose with various secondary disazo dyes, other first components being metanilic and sulphanilic acids, H-acid and its p-toluene-sulphonic ester, 4-amino-1 : 3-dimethyl-benzene-5-sulphonic acid, and 2-aminonaphthalene-4:8-disulphonic acid, other middle components being aniline, 1-aminonaphthalene, and the methyl and ethyl ethers of 3-amino-4-cresol, and other end components being N-benzoyl-2 : 5 : 7-acid, 1-aminonaphthalene-4- sulphonic acid, 1-oxy-8-ethoxynaphthalene- 3:6-disulphonic acid, N-(2<1>-carboxy) phenyl- 2: 5: 7-acid (coupled alkaline), 1-phenylaminonaphthalene-8-sulphonic acid, N-phenyl-H-acid (coupled alkaline), H-acid (coupled alkaline), 8- chloro-naphthol-3 : 6-disulphonic acid. N-benzoyl- H-acid, and N-phenyl-2 : 5: 7-acid. This subjectmatter does not appear in the Specification as accepted.