CH292688A - Process for the production of a vat dye. - Google Patents

Description

  

  Additional patent to main patent no. 288428. Process for the production of a vat dye. It has been found that a valuable vat dye is obtained if 1,4-diaminoanthraquinone-6-methylsulfone is treated with benzoylic agents until two benzoyl radicals appear.



  The new dye dissolves in concentrated sulfuric acid with a pale red color and dyes cotton from an olive-colored vat in burgundy tones, which change into pure, particularly light, violet tones when soaking. The dye is also suitable for printing according to the usual potash process.



  As benzoylating agents come in particular special reactive, functional derivatives such. B. the halides of benzoic acid and especially benzoyle chloride, into consideration. The reaction is advantageously carried out in an inert organic solvent, such as. B. nitrobenzene, at elevated tempera ture.



  <I> Example: </I> 63 parts of 1,4-diaminoanthraquinone-6-melicysulfone are suspended in 850 parts of dry nitrobenzene. After adding <B> 70 </B> parts of benzoyle chloride, the mixture is stirred at 135 to 140 for 21/2 hours. The dye which precipitates out in burgundy crystals on cooling is filtered off with suction, washed well with boiling alcohol and dried.



       1,4-diaminoanthraehinone-6-methylsulfone can e.g. B. from 1-Aminoanthraeliinon-6-methyl sulfone or from a mixture of the 6- and 7-isomers, represented by nitration of the oxamic acid and subsequent reduction of the nitro group by the usual methods who the. 1-Amino-4-nitroanthraquinone-6-methylsulfone forms red needles when recrystallized from nitrobenzene.



       1-Aminoanthraquinone-6-methylsulfone can be obtained as follows: 229 parts of anthraquinone-2-methylsulfone are slowly added to 480 parts of monohydrate at room temperature. With stirring, the temperature is increased to 80 and then a mixture of 64 parts of nitric acid (96%) and 64 parts of monohydrate is added dropwise over the course of one hour, the temperature increasing to 90.

   After half an hour of stirring at 100 is allowed to cool, then carefully carried out in ice and water, suction filtered, washed neutral and dried. For the separation of isomers who the z. B. 130 parts of nitration product at 1.0 in 1000 parts of 95 o / o sulfuric acid and stirred until dissolved. Then 188 parts of 50% sulfuric acid are added dropwise at 10 to 15 in about half an hour and afterwards at 10 to 12 for 31/2 hours. touched.

   The precipitated 1-nitroanthraquinone-6-methylsulfone is filtered off with suction, washed out with 88% sulfuric acid and discharged into ice and water. The resulting suspension is filtered off again, blown until neutral and dried.

   With sodium sulfhydrate in aqueous suspension at 64 to 67, 1-aminoanthraehinoii-6-metiliy isulfone with a melting point of? 49 (uncorr.) Is obtained, which crystallizes in red-brown needles.

 

Claims (1)

PATENT CLAIM A process for the production of a vat dye, characterized in that 1,4-diaminoanthraehinone-6-methylsilphonone is treated with benzoylic agents until two benzoyl radicals appear. The new dye dissolves in concentrated sulfuric acid with a mass red color and dyes cotton from olive-colored Iiüpa in burgundy tones, which change into pure, particularly lielite-fast, violet tones when soapy. The dye is also used for printing using the usual potash method. SUBCLAIMS 1. Process according to patent claim, characterized in that the benzoyl chloride used is benzyl chloride. ?. Process according to patent claim, as it is characterized by the fact that the reaction is carried out in an inert organic solvent at an elevated temperature.