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Carbon black (with subtypes acetylene black, channel black, furnace black, lamp black and thermal black) is a material produced by the incomplete combustion of coal tar, vegetable matter, or petroleum products, including fuel oil, fluid catalytic cracking tar, and ethylene cracking in a limited supply of air.
With a history dating back to the early eighteenth century, Prussian blue remains a popular artistic pigment. Studies of Prussian Blue lead to discoveries about hydrogen cyanide . It is an antidote for heavy metal poisoning, and is famed for being used to color the uniforms of the Prussian army in the eighteenth century.
Bone char is primarily made from cattle and pig bones; however, to prevent the spread of Creutzfeldt–Jakob disease, the skull and spine are no longer used. [2] The bones are heated in a sealed vessel at up to 700 °C (1,292 °F); the oxygen concentration must be kept low while doing this, as it affects the quality of the product, particularly its adsorption capacity.
The color of chemicals is a physical property of chemicals that in most cases comes from the excitation of electrons due to an absorption of energy performed by the chemical. The study of chemical structure by means of energy absorption and release is generally referred to as spectroscopy .
Color theory, or more specifically traditional color theory, is a historical body of knowledge describing the behavior of colors, namely in color mixing, color contrast effects, color harmony, color schemes and color symbolism. [1] Modern color theory is generally referred to as color science.
In color theory, a tint is a mixture of a color with white, which increases lightness, while a shade is a mixture with black, which increases darkness. Both processes affect the resulting color mixture's relative saturation. A tone is produced either by mixing a color with gray, or by both tinting and shading. [1]
The concept of primary colors has a long, complex history. The choice of primary colors has changed over time in different domains that study color. Descriptions of primary colors come from areas including philosophy, art history, color order systems, and scientific work involving the physics of light and perception of color.
In one modern commercial usage of the word, atramentum is a deep black colouring substance manufactured by a reaction of an iron salt with tannic acid (the tannic acid for this purpose is often extracted from oak bark). It is a historically important black dye or pigment fundamentally different from carbon black or black iron oxide pigments. It ...