Patent GB-462968-A (GB)
Title: Preparation of improved colour lakes
IPC: C09B69/04
Filed: 1935-06-12
Abstract: Colour lakes are manufactured by precipitating soluble dyestuffs or colour-producing compounds, if desired on to bases or substrata, by means of precipitants containing titanium compounds.  In the case of acid dyestuffs, titanium compounds may be used in place of barium and calcium compounds.  With basic dyestuffs or their leuco compounds there may be used heteropoly compounds of titanium with molybdic, tungstic, arsenic, phosphoric, silicic, selenious or antimonic acid, e.g. titaniummolybdenum, titanium - tungsten, titaniummolybdenum-tungsten or titanium-phosphomolybdenum-tungsten complexes (obtainable by the addition of a solution of a suitable salt of titanium, e.g. titanium sulphate, titanium tetrachloride, titanium potassium oxalate or titanium phosphate, to a solution of the other ingredients, boiling or evaporating, and salting out the titanium complex, e.g. by means of ammonium or sodium chloride). Compounds of titanium with organic hydroxy compounds, e.g. glycerol or glycol (obtainable by reacting an anhydrous halide compound of titanium with the organic hydroxy compound, e.g. by reacting titanium tetrachloride with glycerol to form a titanium glycerol compound containing combined halogen and, if desired, partially or wholly expelling the free hydrochloric acid by heating), may be used as precipitants, particularly for acid dyestuffs.  The properties of the lakes from basic or acid dyestuffs and titanium precipitants are in many cases improved by carrying out the lake formation in the presence of organic hydroxy compounds, e.g. glycerol or glycol.  The titanium precipitants may be used in conjunction with other precipitants, or the dyestuff may be partially precipitated with known precipitants and a titanium precipitant then added, if desired in excess.  The precipitation may be carried out at ordinary or elevated temperatures, and the lake paste may be subsequently heated or boiled at atmospheric pressure or heated under increased pressure. In examples: (1) Rhodamine B is precipitated by means of a titanium molybdo-tungstate solution, prepared by boiling an aqueous solution of sodium tungstate, sodium molybdate and titanium tetrachloride; (2) Brilliant Green Y is similarly precipitated; (3) Methyl Violet 2B is precipitated by means of a solution prepared by boiling an aqueous solution of sodium tungstate, sodium molybdate, sodium phosphate and titanium tetrachloride; (4) a solution of titanium phosphate and oxalic acid is added to a solution of Methyl Violet 2B and sodium tungstate containing alumina-blanc-fixe base in suspension; (5) Acid Scarlet 2R is precipitated on alumina-blanc-fixe by means of a solution of titanic hydrate in hydrochloric acid; (6) Quinoline Yellow is precipitated on alumina hydrate by means of a solution of titanium tetrachloride; (7) Erioglaucine A high conc. is precipitated on alumina hydrate by means of a compound from titanium tetrachloride and glycerol; (8) in the process of (7), the dyestuff is first partially precipitated by means of barium chloride; (9) Acid Scarlet 2R is precipitated on alumina-blanc-fixe by means of a compound from titanium tetrachloride and glycerol.  Reference has been directed by the Comptroller to Specifications 254,350, [Class 2 (iii), 365,534, and 408,492.ALSO:Heteropoly compounds of titanium with molybdic, tungstic, arsenic, phosphoric, silicic, selenious or antimonic acid, e.g. titaniummolybdenum, titanium-tungsten, titaniummolybdenum-tungsten and titanium-phosphomolybdenum-tungsten complexes, are manufactured by adding a solution of a suitable salt of titanium, e.g. titanium sulphate, titanium tetrachloride, titanium potassium oxalate or titanium phosphate, to a solution of the other ingredients, boiling or evaporating, and salting out the titanium complex, e.g. by means of ammonium or sodium chloride.  In examples, the following compounds are reacted in boiling aqueous solution: (1) sodium tungstate, sodium molybdate and titanium tetrachloride; (2) as in (1) with the addition of sodium phosphate.  Reference has been directed by the Comptroller to Specifications 254,350, [Class 2 (iii)], 365,534, and 408,492, [both in Group IV].