A Few Things About Black Dye:

There are 4 blacks. Each has a different color cast. All except #250 work well in direct application methods like tie-dye where the fabric is kept moist long enough for the dye to develop full color. You will see some differences depending upon which you use, your particular situation, and your techniques. When vat dyeing (solid shade dyeing), there are some clear differences...

#44 Better Black

Vat dyes with a purple-blue cast and edges are blue in tie-dye.

#39 Black

Vat dyes with a green cast and edges are blue in tie-dye.

#250 Jet Black

This is the most concentrated of all the blacks and gives the deepest black when used for vat dyeing with hot tap water (130° to 150°F).

#300 New Black

Vat dyes with a very blue cast and edges are blue in tie-dye.

For best vat dyed blacks, use Dharma Dye Fixative in a rinse. Black is a tough color - use a lot of dye and when vat dyeing, double the salt. Do NOT use Fiber Reactive Procion Dye to get black on silk, use acid dye on wool and silk for solid black.