Direct Black 22

Colour Fastness Test

Direct Black 22 (Direct fast black GF) alias direct gray AB, direct black L-2BG. Appearance is generally gray-black powder. Water solubility is good, soluble in water is purple-black, dye is purple black in concentrated sulfuric acid, dark brown precipitate after dilution In the concentrated nitric acid, it is a reddish brown solution and a precipitate. The aqueous solution with concentrated hydrochloric acid has a brownish black precipitate, and the concentrated sodium hydroxide turns dark blue red. When the copper and iron ions are slightly changed.

Mainly used for cotton, viscose, wool/stick,nylon/rayon blended fabric dyeing and printing, also used in leather and paper dyeing.

Use condition:

1. Direct Fast Black VSF600 dyed cotton or viscose fiber has green light black. Poor transferability, sensitive to salt, slow temperature rise during dyeing and salt addition to control dyeing, uniform color can be obtained. The highest dyeing temperature is 100 ° C. After dyeing, treated with copper salt, the microstrip is blue-red and black.

2. Direct Fast Black VSF600  is also used to dye silk and its fabric. When cotton, viscose fiber and other fibers are dyed in the same bath, silk and wool are lighter than cotton and viscose, and nylon has stain, divine vinegar. Slim and stained, three vinegar fiber does not stain.

3. Direct black 22 can be used for direct printing of cotton or viscose fabric. When printing dark pattern, add urea, disodium hydrogen phosphate, soda ash or sodium hydroxide to adjust the color paste. Also used for ground color discharge, pull White performance is better.