直接紫51是λ| max |为549nm的偶氮染料。提供的其他直接染料包括：直接红23，直接红80，直接红81，直接黄27，直接黄50 ，直接蓝15和直接蓝71。 Direct Violet 51 is an azo dye with a λ|max|of 549 nm. Other direct dyes offered include: Direct red 23 , Direct red 80 , Direct red 81 , Direct yellow 27 , Direct yellow 50 , Direct blue 15 and Direct blue 71 . Application Direct Violet 51 is an azo dye with a λmax of 549 nm.