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Science Of Pigment

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All paint is made from an essential ingredi-ent known as pigment. These tiny particles are ground coloured material were first ex-tracted from earth or clay. Even though we continue to use age old processes to prepare pigments and convert them into paint, modern pigments are synthesized in labora-tories.

SCIENCE OF PIGMENT

INTRO

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The following properties are taken into consid-eration when talking about the quality of both synthetic and natural pigments:

Lightfastness: the rate at which a pigment fades when exposed to light.Heat stability: how pigments react when ex-posed to heat.Toxicity: the degree to which it can damage a living or non-living thing.Tinting strenght: how much pigment is re-quired to produce a particular shade.Opacity or transparency: whether one can easily see the under layers of paint once the top layer is dry.

SCIENCE OF PIGMENT

SCIENCE OF PIGMENT

INTRO


The source of blue pigment used to make ultramarine is the semi-precious stone- lapis lazuli. Natural ultramarine is the most difficult to produce because the hard lapis lazuli must be ground into a fine powder in order to make paint. The earliest noted source of the colour were in Afghani-stan.

Blue was used very sparingly in art be-cause of how difficult this colour was to produce. Artists would go as far as to only paint the top layer of blue with ultramarine to cut down costs of painting.

SCIENCE OF PIGMENT

BLUE


Azurite is a soft, blue mineral of copper that has many uses including the production of blue pigment. The process to produce the colour azure is similar to making its more expensive cousin.

However, since it is a mineral of copper, the pigments turn slightly green when added to oil and green-gray when added to egg yolk (also used as a base in natural paints).

SCIENCE OF PIGMENT

BLUE



Another shade of blue that has an extensive history is Indigo. The colour Indigo is named after India, the earliest known pro-duction center of this pigment. The rela-tively cheaper means of production than ul-tramarine made the colour an important trade commodity.

It was exported west as far as Greece and Rome in the 7th century BC as a luxury item. Indigo is produced by fermenting the leaves of the Indigofera tinctoria plant and mixing it with dye to form a blue-coloured powder.

SCIENCE OF PIGMENT

BLUE



Cerulian blue was discovered in 1805 by a man named Andreas Höpfner. It is made from cobalt and is prized because of its pure colour. It is particularly prized in the art world because it is opaque, it does not fade easily, and it does not emit any hues of green (unlike other blue pigments).

SCIENCE OF PIGMENT

BLUE


Vermilion is an opaque orange-red pig-ment that occurs in the mineral cinnabar. It is one of the oldest used colours in the world as cinnabar is a common mineral found around the world.

The mineral is ground into a fine powder and heated with mercury and sulfur before it is ready to be mixed with a paint-base. However it is also used without these chemi-cals like in India where married women use Sindoor, a red streak of vermilion in the parting of their hair.

SCIENCE OF PIGMENT

RED


Carmine, also known as crimson lake or cochineal red is a bright red colour de-rived from the aluminium salt of carminic acid. This might sound complicated but this acid is found naturally in the cochineal insect.

The insects are dried and boiled in water to release the pigment. The water is them treated with a chemical to make this liquid into a powdered pigment.

SCIENCE OF PIGMENT

RED


Madder lake sounds like the name of a body of water in a fairytale but in fact is the name of a pigment that has been used for centuries. This natural pigment is ex-tracted from the roots of plants of the 'madder' family. The outer brown layer of the root gives a common variety of the dye while the inner yellow layer turns bright red when fer-mented.

SCIENCE OF PIGMENT

RED


Malachite is used in the production of green pigment much in the same way as Ul-tramarine. This copper carbonate mineral occurs naturally in the Ural mountains of Russia, many parts of Africa, France, Italy and the United states.

Paris green is an inorganic compound of copper. This poisonous substance is named Paris green because it was used to kill the rats in Parisian sewers. The com-pound can be ground into a fine powder to produce a lighter, vivid green or left a little coarser for a darker shade. It is used even today in paint production despite its hightoxicity.

SCIENCE OF PIGMENT

GREEN


A highly expensive green pigment is Cobalt green, made from the element from which it gets its name. The green ex-tracted from cobalt fades very easily when exposed to light. The combination of high cost and because it fades easily is the cause for its disuse. However scientists found that cobalt has certain magnetic properties that has increased the efficiency of computer storage devices.

SCIENCE OF PIGMENT

GREEN


The colour India Yellow used to be produced by collecting cow urine of cattle that had only been fed mango leaves. The urine was collected in pots and heated over a fire. The concentrate was filtered and the remaining sediment was made into balls, then dried and then made into yellow paint in Europe. It was a preferred shade of yellow because of its florescent hue.

Naples yellow, also known as anti-mony yellow, is one of the oldest synthetic pigments around. The old masters of Europe used this pigment extensively but isnot used anymore because it is very toxic.

SCIENCE OF PIGMENT

YELLOW


The colour gets its name from the natural deposits of lead antimoniate which was ex-tracted from Mt. Vesuvius just outside of Naples.

Hansa yellow is a synthetic pigment used in inks, and oil and acrylic paint. It was first made in Germany just before WWI and has replaced its predecessors such as Cadmium yellow, Chrome yellow, orpiment, and gamboge because it is not toxic.

Image references:Indian pigmantssource: www.wikipedia.org. This file is licensed under the creative commons attribution 2.0 generic.

SCIENCE OF PIGMENT

YELLOW


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Download - Science of Pigment – Mocomi Kids

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