Basic blue 9, is also known as Methylene Blue, Methylene blue BB, or methyl blue. It is a golden red flash or flash golden bronze powder. Soluble in water, slightly soluble in alcohol, blue. Case of concentrated sulfuric acid is yellow green, blue diluted. In concentrated nitric acid in the Gray-green, added sodium hydroxide solution is purple and dark purple precipitate, add hydrochloric acid unchanged.

C.I.: 52015

CAS NO. :  61-73-4

Molecular Formula: C₁₆H₁₈ClN₃S

Molecular Weight: 319.858

Strength: 100%

Packing: Packed in 25kgs iron drums, plastic bags.

Application Instructions: 
Basic blue 9 is used for silk, wool dyeing, the light fastness is poor;
When used as tannin mordant dyeing for cotton dyeing, light fastness is 3;
Basic blue 9 or methyl blue, was previously used for the direct printing of cotton, but now, it is rarely used in this way;
Other uses including pigment for the paper, bamboo, wood color, for the manufacture of ink and color lake pigments and biological, bacteriological stain;
Also used as solvent dyes.