Patent Blue V Food Color is also known by the name of Sulphan Blue, Acid Blue 3, Food Blue 5, and comprises dark bluish synthetic dye that finds use as food coloring and food additive. With appearance of violet powder, it comes in varying colors depending on pH value of medium (deep blue in basic medium and yellowish-green in acidic medium).

Further, in medicine, patent blue V finds usage in lymphangiography as well as in sentinel node biopsy as dye to color lymph vessels so that these can further be injected with X-ray contrast medium.