Pyrogallol CAS No.: 87-66-1 is made by heating the gallic acid and losing carbon dioxide.Used for making azo dyes, anthraquinone dyes and so on, and used in gas analysis and imaging agents. 
1. for the preparation of metal colloidal solution, leather coloring, fur, hair and other dyeing, etch, etc., and can be used as film developer, infrared photographic thermosensitive agent, styrene and polystyrene inhibitor, pharmaceutical and dye intermediates, and analytical reagents. Pyrogallol is used as an absorbent for oxygen in gas analysis. It is used for powder, hair care and hair dye in cosmetics.
It is mainly used for producing developer, retarding agent and infrared photographic thermosensitive agent. It is also used as the intermediate of medicine and dye.
2. as an analytical reagent, reducing agent and developer
3. used for the analysis and determination of oxygen, antimony, bismuth, cerium, iron, molybdenum, tantalum and niobium; used in gas analysis to absorb oxygen; used for chromogenic reactions of nitrite, molybdenum, niobium, titanium, cerium, bismuth, copper, vanadium, iron, iodate, etc.
4. metal complexing agent. The weight analysis was used to determine bismuth and antimony. A reducing agent for gold, silver, mercury salts, phosphotungstic acid and phosphotungstic acid is used for oxygen absorption in gas analysis. Titanium, iron and aluminum are separated from tantalum and niobium. It is used for the color reaction of nitrite, molybdenum, niobium, titanium, cerium, bismuth, copper, vanadium, iron, iodate and so on.