This section is from the "Henley's Twentieth Century Formulas Recipes Processes" encyclopedia, by Norman W. Henley and others.
This black is produced by carefully oxidizing aniline hydrochloride. The exact stage of oxidation must be carefully regulated or the product will be a different body (qui-none). There are several suitable oxidizing agents, such as chromic acid, potassic bichromate, ferrocyanide of potassium, etc., but one of the easiest to manipulate is potassic chlorate, which by reacting on copper sulphate produces potassic sulphate and copper chlorate. This is easily decomposed, its solution giving off gases at 60° F. which consist essentially of chloride anhydrate. But one of the most useful agents for the production of aniline black is vanadate of ammonia, 1 part of which will do the work of 4,000 parts of copper. Many other salts besides copper may be used for producing aniline black, but the following method is one of the best to follow in making this dye:
Aniline hydrochloride.............. 40 parts
Potassic chlorate.... 20 parts
Copper sulphate.... 40 parts
Chloride of ammonia (sal ammoniac) 16 parts
Warm water at 60° F............... 500 parts
After warming a few minutes the mass froths up. The vapor should not be inhaled. Then set aside, and if the mass is not totally black in a few hours, again heat to 60° F., and expose to the air for a few days, and finally wash away all the soluble salts and the black is fit for use.
Make a solution of
Aniline (fluid measure) 30 parts Toluidine (by weight). 10 parts
Pure hydrochloric acid, B. P. (fluid measure) 60 parts
Soluble gum arabic (fluid measure)..... 60 parts
Dissolve the toluidine in the aniline and add the acid, and finally the mucilage.
Mix together at gentle heat:
Starch paste...... 13 quarts
Potassic chlorate .. 350 scruples Sulphate of copper. 300 scruples
Sal ammoniac..... 300 scruples
Aniline hydrochloride............ 800 scruples
Add 5 per cent of alizarine oil, and then steep it for 2 hours in the dye bath of red liquor of 2.5° Tw. Dye in a bath made up of 0.5 ounce of rose bengal and 1.5 ounces of red liquor to every 70 ounces of cotton fabric dyed, first entering the fabric at 112° F., and raising it to 140° F., working for 1 hour, or until the desirable shade is obtained; then rinse and dry.
Dissolve in a vessel (a) 8.5 parts of chloride of copper in 30 parts of water, and then add 10 parts chloride of sodium and 9.5 parts liquid ammonia.
In a second vessel dissolve (b) 30 parts aniline hydrochlorate in 20 parts of water, and add 20 parts of a solution of gum arabic prepared by dissolving 1 part of gum in 2 parts of water.
Finally mix 1 part of a with 4 parts of 6; expose the mixture to the air for a few days to develop from a greenish to a black color. Dilute for use, or else dry the thick compound to a powder.
If new liquor is used as the mordant, mix 1 part of this with 4 parts of water, and after working the fabric for 1 to 2 hours in the cold liquor, wring or squeeze it out and dry; before working it in the dye liquor, thoroughly wet the fabric by rinsing it in hot water at a spring boil; then cool by washing in the dye bath until the shade desired is attained, and again rinse and dry.
The red liquor or acetate of aluminum may be made by dissolving 13 ounces of alum in 69 ounces of water and mixing this with a solution made by dissolving 71 ounces of acetate of lime, also dissolved in 69 ounces of water. Stir well, allow it to settle, and filter or decanter off the clear fluid for use, and use this mixture 2.5° Tw.
The fabric is first put into the stannate of soda mordant for a few minutes, then wrung out and put into the alum mordant for about the same time; then it is again wrung out and entered in the dye bath at 120° F. and dyed to shade desired, and afterwards rinsed in cold water and dried.
The dye bath is made of 1/2 ounce of rose bengal per gallon of water. If fast pink is the dye used, the mordant used would be Turkey red oil and red liquor. Use 8 ounces of Turkey red oil per gallon of water. Put the fabric into this, then wring out the textile and work in red liquor of 7° Tw. for about 2 hours, then wring out and dye in a separate bath made up of eosine, or fast pink, in water in which a little alum has been dissolved.