Direct Blue 151 is a water-soluble direct (azo) dye primarily used to color cellulose fibers such as cotton, linen and viscose; it appears as a bluish-black to reddish-blue powder and is sold under names like Direct Copper Blue 2R (C.I. 24175).
Direct Blue 151 is Blue-black powder. Soluble in water for blue purple or purple solution, and adequate soluble in ethanol for red light purple.
Direct Copper Blue 2B,Direct Blue Light Fast R,Copper Blue 2R
It Mainly used for cotton, linen, rayon and other cellulose fibers, rayon / brocade fabric dyeing, leather and paper pulp can also be used for coloring.
| Density | 1.60 |
| Dyeing Depth % | 2 |
| Light Fastness | 2-3 |
| Washing Fatness | 4 |
| Rubbing Fastness(dry) | 4-5 |
| Rubbing Fastness(wet) | 2-3 |
It is described as having relatively high staining strength and good rub fastness when properly fixed; however, wet rubbing and poor fixation can still cause migration. Use recommended after-fixation and thorough washing to minimize staining in mixed-fiber goods.
It is primarily an exhaust direct dye and is not a reactive dye; printing is possible but requires careful formulation (fixatives, binders and after-fixation) and will not give the same washfastness as reactive systems on cellulose. For durable reactive printing on cotton, consider reactive dyes instead.
