Substances added to printing inks to impart a black color, generally derived from the refining of oil or natural gas. The black pigments primarily in use today are called Carbon Blacks, which can be either Furnace Black or Channel Black, depending on the method by which they are produced. Furnace Black is derived from the "cracking" of natural gas or oil. Channel Black, due to tightened air pollution laws, is no longer manufactured in the United States, although it is quite desirable, and may be imported from other countries if the added expense is warranted.
Black Iron Oxides can either be obtained from natural sources (primarily magnetite) or synthetic sources.
Vegetable Black is the oldest black pigment, but has been replaced almost entirely by Furnace Black.
The black pigments listed above are classified and identified in the Society of Dyers and Colorists' Color Index. Each classification consists of two parts, corresponding to the two parts of the Index: The first part identifies each pigment with a CI number, which accompanies a description, usage, and technical information. The second part lists each pigment by chemical composition, and assigns each one a single number. Thus, Carbon Black above is listed in Part 1 as CI Pigment Black 7 and in Part 2 as No. 77266. These two sets of identifications accompany the individual entries on each separate pigment.