In this preliminary treatment of the blue, the object is to remove the sulphur which retards the solution of the color.

The liquid is prepared as follows: The pigment, previously dried at 150° C., is crushed and finely ground, and contains about 47 per cent. of coloring matter; to this is added 53 per cent. of water.

To this mixture, or slurry, the inventor adds an indefinite quantity of glucose and glycerine of 43° B., having a specific gravity of 1.425. It is then ready for use.—Le Moniteur de la Teinture.


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