India ink is a simple black or colored ink once widely used for writing and printing and now more commonly used for drawing and outlining, especially when inking comic books and comic strips. India ink is also used in medical applications.

India ink was first invented in China, but the English term India(n) ink was coined due to their later trade with India. A considerable number of oracle bones of the late Shang dynasty contain incised characters with black pigment from a carbonaceous material identified as ink. Numerous documents written in ink on precious stones as well as bamboo or wooden tablets. A cylindrical artifact made from black ink has been found in Qin tombs, dating back to the 3rd century BC (Before Christ) during the Warring States or dynastic period, from Yunmeng, Hubei.

Basic India ink is composed of a variety of fine soot, known as lampblack, combined with water to form a liquid. No binder material is necessary: the carbon molecules are in colloidal suspension and form a waterproof layer after drying. A binding agent such as gelatin or, more commonly, shellac may be added to make the ink more durable once dried. India ink is commonly sold in bottled form, as well as a solid form as an inkstick (most commonly, a stick), which must be ground and mixed with water before use. If a binder is used, India ink may be waterproof or non-waterproof.

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