Patent GB-356716-A (GB)
Title: A manufacture of metalliferous dyestuffs
IPC: C09B45/16
Filed: 1930-06-06
Abstract: Varnishes made from nitro- or acetyl-cellulose or natural or artificial resins are coloured by means of complex metal compounds of azo dyes derived from o-oxydiazo compounds and naphthylamines, aminonaphthols, or their N-acyl derivatives, the dyes being free from sulphonic, carboxylic, sulphonamide, or other groups inducing ready solubility in water, the metal compounds being made by metallizing the parent dyestuff in pyridine or other organic base in the absence of water.  Examples are given of the preparation of the chromium compounds of the following dyestuffs and their colourations of nitro- or acetyl-cellulose varnishes 5-nitro-2-aminophenol --> b -naphthylamine (yellowish-green), 2-aminophenol --> b -naphthylamine (blue-green), 4-chlor-2-aminophenol --> b -naphthylamine (blue-green), 4:6-dichlor-2-aminophenol --> b -naphthylamine (bluish-green), 4-nitro-2-aminophenol --> b -naphthylamine (olive-green), 5-nitro-4-chlor-2-aminophenol --> b -naphthylamine (bluish-green), picamic acid --> b -naphthylamine (olive-green), 4-nitro-2-aminophenol --> (acid), 2:5-, 2:7-, or 2:8-aminonaphthol (green), 5-nitro-2-aminophenol --> (acid) 2:5-, 2:6-, 2:7- or 2:8-aminonaphthol (green), 5-nitro-2-aminophenol --> (alkaline), 2:7-aminonaphthol (reddish-blue), 4-chlor-2-aminophenol --> (alkaline), 2:7-aminonaphthol (violet), 4-chlor-2-aminophenol --> (alkaline), 1:7-aminonaphthol (greyish blue-green), 2-aminophenol --> (alkaline), 1:7-aminonaphthol (blue-grey), 4-nitro-2-aminophenol --> (alkaline), 1:7-aminonaphthol (green-grey), 2-aminophenol --> (alkaline), 1-acetamino-7-naphthol (reddish-blue), 4-chlor-, 4-nitro-, and 5-nitro-2-aminopheno similarly give greenish-blue to greyish green-blue products; the ferric compound of the dyestuff 2-aminophenol --> b -naphthylamine gives brownish-violet products, the cobalt, nickel, and manganese compounds of the dyestuff 4-chlor-2-aminophenol --> b -naphthylamine give blue-violet, brownish-violet, and olive-brown products; the aluminium compound of the dyestuff 4-nitro-2-aminophenol --> (alkaline) 1-acetamino-7-naphthol gives violet products.  4-5 parts of the metallized dyestuff per 1000 parts of nitrocellulose varnish in a suitable proportion; the solutions may be used for coating metal, glass, leather, ceramic ware, wood, celluloid, silk, &c.  The Specification as open to inspection under Sect. 91 (3) (a) comprises also the production and use of metal compounds of sulphonated, o-carboxy azo, and o-oxycarboxy azo dyestuffs; examples are given of the preparation chromium compounds of the dyestuffs from 2-aminophenol-4-sulphamide or anthramide acid or p-aminosalicylic acid and b -naphthylamine (bluish-green).  This subject-matter does not appear in the Specification as accepted.ALSO:Azo dyes, complex metal compounds of; lakes; cellulose esters or ethers, dyeing; regenerated celluloses, dyeing.-Azo dyes obtainable by coupling an o-oxydiazo compound with a naphthylamine, an aminonaphthol or an N-acyl derivative thereof and which contain no groups inducing ready solubility in water, such as sulphonic, carboxylic, or sulphonamido groups, are converted into complex metal compounds by treatment with one or more agents yielding metal in presence of an organic base containing no oxyalkyl group and without the addition of water. The products, which are insoluble or sparingly soluble in water, are suitable for dyeing cellulose esters or ethers, for use as pigments, and for incorporation in varnishes having a basis of cellulose or of natural or artificial resins.  Specifie organic bases are pyridine, its homologues and products of hydrogenation, quinoline, aniline, o-, m-, and p-toluidines, benzylamine, n-amylamine, and propylamine, and specified metals are aluminium, copper, zinc, vanadium, and metals of atomic weights between 52 and 59.  The metallization may be effected in presence of alkali metal salts such as sodium acetate, sodium formate, or sodium sulphate and with or without application of pressure. Alternatively the coupling operation to produce the azo dyestuff may be effected in presence of the organic base, and of one or more agents yielding metal without addition of water.  The following examples are specified: (1) A solution of the dyestuff 5-nitro-2-aminophenol --> 2-naphthylamine in pyridine is boiled for 20 hours under reflux with an addition of chromium formate, the solution is filtered, the pyridine is removed from the filtrate by distillation in vacuo, and the residue is purified by washing with hot water; the product dissolved in commercial nitrocellulose varnish gives yellowish-green coatings on metal surfaces.  (2) A solution of the dyestuff 2-aminophenol --> 2-naphthylamine in pyridine is boiled for 20 hours under reflux with an addition of chromium acetate or formate, the solution is filtered and the chromium compound is extracted from the filtrate by addition of water and filtering; its solution in nitrocellulose varnish gives blue-green coatings.  (3) A solution of the dyestuff 4-chloro-2-aminophenol --> 2-naphthylamine in pyridine is boiled for several hours under reflux with an addition of chromium formate or acetate, the solution is filtered, the pyridine is removed from the filtrate by distillation in vacuo and the residue is dried; its solution in nitrocellulose varnish gives blue-green coatings; a similar product is obtainable from the dyestuff 4 : 6-dichloro-2-aminophenol --> 2-naphthylamine.  (4) A solution of the dyestuff 4-nitro-2-aminophenol --> 2-naphthylamine in pyridine is boiled for several hours under reflux with an addition of chromium formate, and the product is isolated as in (3); its solution in nitrocellulose varnish gives olive-green coatings. (5) A solution of the dyestuff 5 - nitro - 4 - chloro - 2 - aminophenol --> 2 - naphthylamine in pyridine is boiled for several hours under reflux with an addition of chromium formate, and the product is isolated as in (2) or (3); its solutions in nitrocellulose and acetylcellulose varnishes give bluish-green coatings.  (6) The dyestuff picramic acid --> 2-naphthylamine in pyridine is boiled for several hours under reflux with an addition of chromium formate, and the product is isolated as in (3); its solution in acetylcellulose varnish gives olive-green coatings.  (7) A solution of the dyestuff 4-nitro-2-aminophenol --> (acid) 2 : 5-aminonaphthol in pyridine is boiled for several hours under reflux with an addition of chromium formate, and the product is isolated as in (3); its solutions in nitrocellulose and acetylcellulose varnishes give yellowish-green coatings; the corresponding products from the dyestuffs having 2 : 7- and 2 : 8-aminonaphthols as coupling components give more bluish and more olive tints respectively.  (8) A chromiferous product is similarly obtained from the dyestuff 5-nitro-2-aminophenol --> (acid) 2 : 7-aminonaphthol; its solutions in nitrocellulose and acetylcellulose varnishes give bluish-green coatings; the corresponding products from the dyestuffs having 2 : 5- and 2 : 8-aminonaphthols as coupling components give yellowish-green and blackish-green coatings respectively, the second product, however, being insoluble in nitrocellulose varnishes; 2 : 6-aminonaphthol may also be used as coupling component.  (9) A solution of the dyestuff 5-nitro-2-aminophenol --> (alkaline) 2 : 7-aminonaphthol in pyridine is boiled for several hours under reflux with an addition of chromium formate, and the product is isolated as in (3); its solutions in nitrocellulose and acetylcellulose varnishes give reddish-blue coatings; the corresponding product having 4-chloro-2-aminophenol as diazo component gives violet coatings.  (10) A chromiferous product is similarly obtained from the dyestuff 4-chloro-2-aminophenol --> (alkaline) 1 : 7-aminonaphthol; its solutions in nitrocellulose and acetylcellulose varnishes give greyish blue-green coatings; similar products are obtainable using 2-aminophenol and 4-nitro-2-aminophenol as diazo components.  (11) A solution of the dyestuff 2-aminophenol --> (alkaline) 1-acetylamino-7-naphthol in pyridine is boiled for several hours under reflux with an addition of chromium formate, the solution is filtered, and the filtrate is evaporated to dryness in vacuo; solutions of the product in nitrocellulose and acetylcellulose varnishes give reddish-blue coatings; the corresponding products having 4-chloro-2-aminophenol, or 4- or 5-nitro-2-aminophenol as diazo components are greenish-blue to greyish-blue.  (12) A solution of the dyestuff 5-nitro-2-aminophenol --> 2-naphthylamine in pyridine is boiled with an addition of ferric acetate, the solution is filtered, and either the product is precipitated by addition of water or the pyridine is removed by distillation in vacuo; solutions of the product in nitrocellulose and acetylcellulose varnishes give brownish-violet coatings.  (13) A solution of the dyestuff 4-chloro-2-aminophenol --> 2-naphthylamine in pyridine is boiled with an addition of cobalt acetate, the solution is filtered, and the filtrate is evaporated to dryness in vacuo; solutions of the product in nitrocellulose and acetylcellulose varnishes give blue-violet coatings; when the cobalt acetate is replaced by nickel acetate and manganese acetate the coatings are brownish-violet and olive-brown respectively. (14) The dyestuff 4-nitro-2-aminophenol --> (alkaline) 1-acetylamino-7-naphthol in pyridine is similarly treated with aluminium acetate; solutions of the product in nitrocellulose and acetylcellulose varnishes give violet coatings.  (15) 4-5 parts of the metalliferous dyestuff are incorporated in 1000 parts of nitrocellulose varnish; the products give transparent coatings, very fast to light, on metal, glass, leather, ceramic ware, wood, celluloid, and silk, and with suitable additions may be converted into a matt or covering varnish.  Specification 309,148, [Class 2 (iii), Dyes &c.], is referred to.