Patent GB-385409-A (GB)
Title: A manufacture of coloured lacquers and plastic masses
IPC: C09B17/04
Filed: 1931-11-24
Abstract: Safranines.--Lacquers and plastic masses made from cellulose or natural or artificial resins are coloured with a sulphonic acid, or an alkali salt thereof, of a dyestuff having the general formula <FORM:0385409/IV/1> in which R1 is H, alkyl or aryl, R2 is H, alkyl, aryl, or aralkyl, R3 is alkyl or aryl and R4 is aryl.  The following examples are specified.  (1) A finished nitrocellulose varnish is coloured with sodium 3 : 6-diphenylnaphthophenosafranine-2 : 7-disulphonate; the product applied in thin layers upon supports of metal, glass, leather, wood, celluloid, silk or cotton gives on drying a transparent coating of a very fast vivid reddish blue colour; by incorporating a higher fatty acid, barium sulphate, zinc oxide or titanium dioxide a mat or covering varnish is obtainable. (2) An alcoholic solution of 3-ethyl-(4<1>-sulpho) benzyl - 6 - (3<1>-carboxy-4<1>-hydroxy) phenylnaphthophenosafranine is mixed with a powdered phenol-formaldehyde resin, the alcohol is removed by evaporation, and the resulting powder is charged into a preheated mould and subjected to a pressure of 150 atm. per sq. cm. for 2 mins. at 180 DEG  C. to obtain a pressed object of a fast violet colour. (3) A dry intimate mixture of a phenol-aldehyde condensation product, asbestos, titanium dioxide, and sodium 3-(4<1>-methoxy) phenyl-6-phenylnaphthophenosafranine - 2 : 7 - disulphonate is made in a rod or ball mill, the resulting powder is preliminarily hardened for 2-3 hours at 70-80 DEG  C. and subjected to a pressure of 150 atm. per sq. cm. for 10 minutes at 160-200 DEG  C. to obtain a deep blue object resistant to heat.  (4) A solution of sodium 3-(2<1>-methoxy) phenyl-6 - phenylnaphthophenosafranine - 2 : 7 - disulphonate, in acetone or another organic solvent such as monomethylglycol is added to a plastic mixture, made by hot kneading, of acetyl-cellulose and p-toluenesulphonamide; after further kneading and cooling the mass falls to a powder which when subjected to a pressure of 100 atm. per sq. cm. at 150 DEG  C. yields pure blue transparent objects; by incorporating fillers such as barium sulphate, zinc oxide or titanium dioxide opaque blue objects are obtainable.  (5) An alcoholic solution of sodium 3-diethyl-6-(3<1>-sulpho-4<1>-diethylamino) phenylnaphthophenosafranine-1-sulphonate is kneaded with a colourless celluloid mass and the mixture is rolled in a calendering machine to obtain plates which, according to their thickness, are light to dark reddish-blue, very fast to light.  In any of the above examples the dyestuff may be replaced by sodium 3-diethyl-6-(3<1>-sulpho-4<1>-amino) phenyl - naphthophenosafranine - 1 - sulphonate.  Sodium-3 : 6-diphenylnaphthophenosafranine-2 : 7-disulphonate (example 1) and the corresponding 3-(4<1>-methoxy) phenyl (example 3), and 3-(2<1>-methoxy) phenyl (example 4) compounds are obtained by oxidizing 2-phenyl-aminonaphthalene-5-sulphonic acid together with 4-amino-2-sulphodiphenylamine and its 4<1>-methoxy and 2<1>-methoxy derivatives respectively, treating the product with bisulphite according to the process of Specification 14962/98, [Class 2, Acids and salts, Organic &c.], causing the resulting isorosinduline-6-sulphonic acid to react with aniline according to the process of Specification 14961/98, [Class 2, Acids and salts, Organic &c.], and converting the product into the sodium salt. 3-Ethyl-(4<1>-sulpho) benzyl - 6 - (3<1> - carboxy - 4<1> - hydroxy) phenylnaphthophenosafranine (example 2) is obtained by condensing 2-phenylaminonaphthalene with 4-nitrosoethylsulphobenzylaniline, oxidizing the condensation product to the isorosinduline, converting this into the 6-sulphonic acid by the process of Specification 14962/98 and causing the product to react with 4-hydroxyaniline -3-carboxylic acid by the process of Specification 14961/98. Sodium-3-diethyl-6-(3<1>-sulpho-4<1>-diethylamino) phenylnaphthophenosafranine-1-sulphonate (example 5) is obtained by oxidizing 2-phenylaminonaphthalene together with 4-amino-1-diethylaminobenzene-3-sulphonic acid and treating the product with bisulphite according to the process of Specification 14962/98 causing the resulting isorosinduline-6-sulphonic acid to react with 4-amino - 1 - diethylaminobenzene - 2 - sulphonic acid according to the process of Specification 14961/98 and converting the product into the sodium salt. Sodium-3-diethyl-6-(3<1>-sulpho-4<1>-amino) phenyl - naphthophenosafranine - 1 - sulphonate is similarly obtained by causing the above isorosinduline-6-sulphonic acid to react with 1 : 4-diaminobenzene-2-sulphonic acid and converting into the sodium salt.  4 - Amino - 2<1> - methoxydiphenylamine - 2 - sulphonic acid is obtained by reduction of the product of condensation of 4-nitro-1-chlorobenzene-2-sulphonic acid and 2-anisidine.  The Specification as open to inspection under Sect. 91 comprises also a reference to the use of 3-ethylbenzyl-isorosinduline chloride and of 3-ethyl-(4<1>-sulpho) benzyl-6-sulphoisorosinduline chloride and an example is given of the incorporation of an acetone solution of 3-ethylbenzyl-6-rosindone in a nitrocellulose varnish containing, if desired, additional solvents such as butyl acetate and the usual softening or plasticizing agents, such as tricresyl phosphate, castor oil or triphenyl phosphate.  This subject-matter does not appear in the Specification as accepted.