n (ca. 1889) Pigment Black 7 (77266) Finely divided carbon formed by any one of the following processes: (1) Incomplete combustion of natural gas in burners under moving channel irons (channel carbon black). (2) Incomplete combustion of natural gas and petroleum in large, closed furnaces (furnace carbon black) (3) Decomposition of gasses in large converters filled with hot refractory brick checkerwork. These carbon blacks vary in particle size and some of them may be surface treated. A generic term for the family of colloidal carbons. More specifically, carbon black is made by the partial combustion and/or thermal cracking of natural gas, oil. Or another hydrocarbon. Acetylene black is the carbon black derived from burning acetylene. Animal black is derived from bones of animals. Channel blacks are made by impinging gas flames against steel plates or channel irons (hence the name), from which the deposit is scraped at internals. Furnace blackis the term sometimes applied to carbon...