In biology, pigment is any material resulting in color in plant or animal cells which is the result of selective absorption. Some biological material has so-called structural color, which is the result of selective reflection or iridescence, usually done with multilayer structures. Unlike structural color, pigment color is the same for all viewing angles. Many biological structures, such as skin, eyes, fur and hair contain pigments (such as melanin) in specialised cells called chromatophores. Butterfly wings typically contain structural color, although many of them contain pigment as well. Creatures that have deficient pigmentation are called albinos.

In the coloring of paint, ink, plastic, fabric and other material, a pigment is a dry colorant, usually an insoluble powder. There are both natural and synthetic pigments, both organic and inorganic ones. Pigments work by selectively absorbing some parts of the visible spectrum whilst reflecting others.

A distinction is usually made between a pigment, which is insoluble, and a dye, which is either a liquid, or is soluble. There is a well-defined dividing line between pigments and dyes: a pigment is not soluble in the vehicle (or matrix) while a dye is. From this follows that a certain colorant can be both a pigment and a dye depending on in which vehicle it is used. In some cases, a pigment will be made by precipitating a soluble dye with a metallic salt. The resulting pigment is called a "lake". Fugitive pigments are non-permanent pigments.

Biological & organic pigments

- Heme/porphyrin-based: chlorophyll, bilirubin, hemocyanin, hemoglobin, myoglobin
- Light-emitting: luciferin
- Lipochromes: - Carotenoids: alpha and beta carotene, anthocyanin, lycopene, rhodopsin
- Xanthophylls: canthaxanthin, zeaxanthin, lutein
- Photosynthetic: chlorophyll, phycobilin
- Organic: Pigment Red 170, phthalocyanine, Phthalo Green, Phthalo Blue,Alizarin, Alizarin Crimson, crimson, Indian Yellow, indigo, quinacridone, Quinacridone Magenta, woad.
- Resin: gamboge
- Polyene enolates: a class of red pigments unique to parrots
- Other: hematochrome, melanin, Phthalocyanine blue, urochrome, Van Dyke brown

Inorganic pigments

- Carbon pigments: bone black (also known as bone char), carbon black, ivory black, vine black, lampblack, Mars black
- Cadmium pigments: cadmium pigments, Cadmium Green, Cadmium Red, Cadmium Yellow, Cadmium Orange
- Iron pigments: Caput Mortuum, Prussian blue, oxide red, red ochre, Sanguine, Venetian red
- Chromium pigments: Chrome Green, chrome yellow
- Cobalt pigments cobalt blue, cerulean blue
- Lead pigments: lead white, Naples yellow, Cremnitz White, Foundation White, red lead
- Copper pigments: Paris Green, verdigris
- Titanium pigments: titanium dioxide, titanium white
- Sulfur pigments: ultramarine, Ultramarine Green Shade, French Ultramarine, vermilion
- Chrome pigments: viridian
- Zinc pigments: zinc white
- Clay earth pigments: sienna, raw sienna, burnt sienna, umber, raw umber, burnt umber, yellow ochre


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