Black 7984, Food Black 2, or C.I. 27755, is a brown-to-black synthetic diazo dye. It is often used as the tetrasodium salt.

When used as a food dye, it has E number E152. Its use in food has not been permitted in the United States and in the European Union since 1984.^{[citation needed]} It is also not permitted in Australia and Japan.^{[citation needed]}

Black 7984 is also used in cosmetics.

• Carbon black