Patent GB-372761-A (GB)
Title: Improvements in the manufacture and production of coloured masses and solutions thereof
IPC: C09B51/00
Filed: 1930-12-31
Abstract: Nitro, phthalein, and triarylmethane dyes; lakes; cellulose carboxylates, nitrates, and ethers.--The process of the parent Specification for obtaining coloured masses containing cellulose esters or ethers, or artificial or natural resins, including urea-formaldehyde condensation products, and solutions thereof in organic solvents, such as lacquers or varnishes, is modified in that the dyes containing sulphonic or carboxylic groups employed are nitranilines, or substitution products thereof, containing such acid groups.  Dyes of this type are, for example, sulphonic and carboxylic acids of nitranilines or halogen, alkyl, aryl, or substituted aryl derivatives thereof, e.g. o-nitranilinesulphonic acids, dinitrodiphenylaminecarboxylic acids and dinitrodiphenylamine-mono- and disulphonic acids.  The following examples are specified: (1) The dicyclohexylamine salt of 2-nitraniline-4-sulphonic acid (obtained by interaction of equivalent amounts of dicyclohexylamine hydrochloride with the sodium salt of the acid) is dissolved in a nitrocellulose lacquer; the product gives greenish-yellow coatings fast to light. (2) The cyclohexylamine salt of 2 : 4-dinitrodiphenylamine-3<1> (or 4<1>-)-sulphonic acid or of 2 : 6-dinitrodiphenylamine-4-sulphonic acid is dissolved in a nitrocellulose lacquer.  (3) The dicyclohexylamine salt of 2 : 6-dinitrodiphenylamine-4 : 3<1>- disulphonic acid (obtained by interaction of equivalent amounts of dicyclohexylamine in hydrochloric acid solution with the dipotassium salt of the acid) is dissolved in a lacquer of ethyl alcohol and Manila copal; the product gives brilliant golden yellow coatings, fast to light; the dyestuff may be replaced by the piperidine salt of 2 : 4-dinitrodiphenylamine-6 : 4<1>-disulphonic acid, the cyclohexylamine salt of 2 : 6-dinitro-4<1>-chlorodiphenylamine-4 : 3<1>-disulphonic acid-or the dicyclohexylamine salt of 2 : 6-dinitrodiphenylamine-4 : 4<1>-disulphonic acid or of 2 : 6, dinitro - 4<1> - chlorodiphenylamine - 4 : 3<1> - disulphonic acid.  (4) 2 : 4-Dinitrodiphenylamine-3<1>-carboxylic acid is triturated with a nitrocellulose lacquer with addition of dicyclohexylamine to obtain a clear yellow product.  (5) The salt obtained by interaction of the dyestuff Rhodamine B with the sodium salt of 2 : 4-dinitrodiphenylamine-3<1>-sulphonic acid is dissolved in a nitrocellulose or alcohol-Manila copal lacquer; the product gives brilliant scarlet red coatings of greater fastness to light and only slightly yellower than those obtainable with Rhodamine B itself.  (6) The cyclohexylamine salt of 2 : 6-dinitro-4<1>-chlorodiphenylamine-4 : 3<1>-disulphonic acid is kneaded into a plastic mass of celluloid moistened with ethyl alcohol to obtain a homogeneous yellow product. (7) The cyclohexylamine salt of 2-nitro-5-chloraniline-4-sulphonic acid is dissolved in a nitrocellulose lacquer; the product gives greenish-yellow coatings.  (8) The dicyclohexylamine salt of 2 : 6-dinitro-4<1>-hydroxy-3<1>-carboxydiphenylamine-4 : 5-disulphonic acid is dissolved in a nitrocellulose lacquer; the product gives brilliant light brown coatings.  (9) The salt obtained by interaction of the dyestuff Methyl violet B extra with the ammonium salt of 2-nitraniline-4-sulphonic acid is dissolved in a nitrocellulose lacquer; the product gives dark violet coatings.  (10) The salt obtained by interaction of the dyestuff Rhoduline blue 6G with the sodium salt of 2 : 4-dinitrodiphenylamine-3<1>-sulphonic acid is dissolved in a spirit lacquer; the product gives blue-green coatings. Specifications 277,371, 293,766, [both in Class 2 (iii), Dyes &c.], and 350,978 are referred to.  2 : 4-Dinitrodiphenylamine-6 : 4<1>-disulphonic acid is obtained by condensation of 2 : 4-dinitrochlorobenzene-6-sulphonic acid with sulphanilic acid in presence of sodium carbonate.  2 : 6 - Dinitro - 4<1> - chloro - diphenylamine-4 : 3<1>-disulphonic acid is obtained by condensation of 2 : 6-dinitrochlorobenzene-4-sulphonic acid with 4-chloraniline-3-sulphonic acid in presence of potassium carbonate. 2 : 6-Dinitrodiphenylamine - 4 : 4<1>-disulphonic acid is obtained by condensation of 2 : 6-dinitrochlorobenzene-4-sulphonic acid with sulphanilic acid in presence of potassium carbonate.  2 : 6 - Dinitro - 4<1> - hydroxy - 3<1> - carboxydiphenylamine-4 : 5<1>-disulphonic acid is obtained by condensation of 2 : 6-dinitrochlorobenzene-4-sulphonic acid with aminosulphosalicylic acid (NH2 : COOH : OH : SO3H = 1 : 3 : 4 : 5) in presence of potassium carbonate.