Hydroquinone 123-31-9

Chemical properties Hydroquinone is also known as hydroquinone and 1.4-benzene. Molecular formula C6H6O2. Molecular weight 110.11. Colorless or white crystals. It changes color easily when exposed to light in the air. Its aqueous solution can oxidize to brown in the air, and oxidizes faster in alkaline medium. Melting point 170-171℃, boiling point 285-287℃, relative density 1.33215, UVλmax 288nm in water. It is easily soluble in hot water, ethanol and ether, and slightly soluble in benzene. It is chemically active and easily oxidized, and can also undergo esterification, substitution and other reactions.
Hydroquinone is an important organic developer that can only work in a strong alkaline solution. The reduction speed is slower than that of metol, but once the image appears, the density increases rapidly, and a larger contrast can be obtained. The fastest development temperature is 27°-29℃, slows down below 15℃, and almost stops below 5℃. Large amounts can make photos look warm. Used as a common photographic developer; physical developer and redeveloper reducing agent. Generally used in combination with phenidone and metol. Uses: Colorimetric determination of phosphorus, magnesium, niobium, copper, silicon and arsenic; polarographic and volumetric determination of iridium; reducing agent for heteropolyacids; reducing agent for copper and gold; testing of phosphates, tungstates, nitrates, nitrites, selenium and tellurium; developer; antioxidant; desulfurizer for fertilizer industry; urea synergist. Uses: Hydroquinone is an intermediate for the herbicides quizalofop-p-butyl, fluazifop-p-butyl, thiazolyl-butyl, oxadiazol-butyl, fluazifop-p-butyl and lactofen-butyl, and is also an intermediate for medicine and dyes. Uses: Hydroquinone is mainly used as a photographic developer. Hydroquinone and its alkylated products are widely used as inhibitors added during the storage and transportation of monomers, with a common concentration of about 200 ppm. Hydroquinone monomethyl ether is an intermediate of edible oil antioxidant BHA; hydroquinone dimethyl ether is an intermediate of dyes, organic pigments and spices; hydroquinone diethyl ether is an intermediate of photosensitive pigments and dyes. Hydroquinone is also used to prepare N, N'-diphenyl p-phenylenediamine, which is an antioxidant and deodorant for rubber and gasoline.