GB/T 1650-2009 is formulated around direct blue B (direct lake blue 5B). The standard clarifies the product definition, specifies the technical requirements of Appearance, Strength, Color Light, etc., to ensure the quality of dyestuff Color. At the same time, the corresponding test methods are given to detect various indicators, standardize the inspection rules, and the relevant requirements for product Encasement, marking, transportation and storage. This standard provides guidelines for the production, quality control and market circulation of direct blue B, helps to ensure product mass, and promotes the standardized development of dyestuff industry.