ANILINE BLACK

Uses

Aniline Black is used in dry toners for electrophotographic laser printers, in pigment inks for ink jet printers, and bound to a protein in the production of an antiserum for cancer therapy inwarm-blooded animals.Aniline Black is an electrical conductor with holes as the main charge carriers. It can act as the cathode material of rechargeable lithium batteries.

Definition

A black dye developed on cotton and other textiles from a bath containing aniline hydrochloride, an oxidizing agent (usually chromic acid), and a catalyzer (usually a vanadium or copper salt).

Flammability and Explosibility

Not classified

Synthesis

3750 L of water and 436 L of 30 % hydrochloric acid are placed in a 8000 L enamelled kettle equipped with a mechanical stirrer, and 150 kg of aniline and 52 kg of otoluidine are then added. With further stirring, 78 kg of sulfuric acid monohydrate is added, and the contents of the kettle are heated to exactly 27 ℃. Starting at this temperature, a 24.5 % solution of sodium dichromate is added in several portions, and the solution is stirred each time for 15 min before the next amount follows. The temperature increases to 29 ℃ with the addition of 318 kg of sodium dichromate solution; further addition of three times 273 kg raises the temperature to 33, 39, and 45 ℃. Then the pigment is immediately isolated in a filter press, washed with 3000 L of water, and dried by blowing. The dried pigment is mixed with 6000 L of deionized water and 500 L of 30% hydrochloric acid and stirred overnight at 25 ℃. The press cake is washed with 8000 L of distilled water, and the pH of the mixture is raised to 5 with 5 kg of sodium carbonate. The isolated product is dried under vacuum at 90 – 95 ℃.Yield: 280 kg Helio Fast Black TW.