Oil paint

Oil paint

Overview

Oil paint is a type of slow-drying paint
Paint
Paint is any liquid, liquefiable, or mastic composition which after application to a substrate in a thin layer is converted to an opaque solid film. One may also consider the digital mimicry thereof...

 that consists of particles of pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 suspended in a drying oil
Drying oil
A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air. The oil hardens through a chemical reaction in which the components crosslink by the action of oxygen . Drying oils are a key component of oil paint and some varnishes...

, commonly linseed oil
Linseed oil
Linseed oil, also known as flaxseed oil, is a clear to yellowish oil obtained from the dried ripe seeds of the flax plant . The oil is obtained by cold pressing, sometimes followed by solvent extraction...

. The viscosity of the paint may be modified by the addition of a solvent such as turpentine
Turpentine
Turpentine is a fluid obtained by the distillation of resin obtained from trees, mainly pine trees. It is composed of terpenes, mainly the monoterpenes alpha-pinene and beta-pinene...

 or white spirit
White spirit
White spirit [CAS 64475-85-0], also known as Stoddard solvent [CAS 8052-41-3] or mineral spirits, is a paraffin-derived clear, transparent liquid which is a common organic solvent used in painting and decorating. In 1924, an Atlanta dry cleaner named W. J. Stoddard worked with Lloyd E...

, and varnish
Varnish
Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish finishes are usually glossy but may be designed to produce satin or semi-gloss...

 may be added to increase the glossiness
Gloss (paint)
Paint and other finishes come in a variety of finish gloss levels, which correspond to different levels of specular reflection.Some common names for levels of gloss include: flat, matte, eggshell, satin, silk, semi-gloss, high gloss. These terms are not standardized, and not all manufacturers use...

 of the dried oil paint film. Oil paints have been used in Europe since the 12th century for simple decoration, but were not widely adopted as an artistic medium until the early 15th century.
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Encyclopedia

Oil paint is a type of slow-drying paint
Paint
Paint is any liquid, liquefiable, or mastic composition which after application to a substrate in a thin layer is converted to an opaque solid film. One may also consider the digital mimicry thereof...

 that consists of particles of pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 suspended in a drying oil
Drying oil
A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air. The oil hardens through a chemical reaction in which the components crosslink by the action of oxygen . Drying oils are a key component of oil paint and some varnishes...

, commonly linseed oil
Linseed oil
Linseed oil, also known as flaxseed oil, is a clear to yellowish oil obtained from the dried ripe seeds of the flax plant . The oil is obtained by cold pressing, sometimes followed by solvent extraction...

. The viscosity of the paint may be modified by the addition of a solvent such as turpentine
Turpentine
Turpentine is a fluid obtained by the distillation of resin obtained from trees, mainly pine trees. It is composed of terpenes, mainly the monoterpenes alpha-pinene and beta-pinene...

 or white spirit
White spirit
White spirit [CAS 64475-85-0], also known as Stoddard solvent [CAS 8052-41-3] or mineral spirits, is a paraffin-derived clear, transparent liquid which is a common organic solvent used in painting and decorating. In 1924, an Atlanta dry cleaner named W. J. Stoddard worked with Lloyd E...

, and varnish
Varnish
Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish finishes are usually glossy but may be designed to produce satin or semi-gloss...

 may be added to increase the glossiness
Gloss (paint)
Paint and other finishes come in a variety of finish gloss levels, which correspond to different levels of specular reflection.Some common names for levels of gloss include: flat, matte, eggshell, satin, silk, semi-gloss, high gloss. These terms are not standardized, and not all manufacturers use...

 of the dried oil paint film. Oil paints have been used in Europe since the 12th century for simple decoration, but were not widely adopted as an artistic medium until the early 15th century. Common modern applications of oil paint are in finishing and protection of wood
Wood finishing
Wood finishing refers to the process of embellishing and/or protecting the surface of a wooden material. The process starts with surface preparation, either by sanding by hand , scraping, or planing. Imperfections or nail holes on the surface may be filled using wood putty or pores may be filled...

 in buildings and exposed metal structures such as ships and bridges. Its hard-wearing properties and luminous colors make it desirable for both interior and exterior use on wood and metal. Due to its slow-drying properties, it has recently been used in paint-on-glass animation
Paint-on-glass animation
Paint-on-glass animation is a technique for making animated films by manipulating slow-drying oil paints on sheets of glass. Gouache mixed with glycerine is sometimes used instead...

. Thickness of coat has considerable bearing on time required for drying: thin coats of oil paint dry relatively quickly.

History


The technical history of the introduction and development of oil paint, and the date of introduction of various additives (driers, thinners) is still - despite intense research since the mid 18th century - not well understood. The literature abounds with incorrect theories and information: in general, anything published before 1952 is to be treated with extreme scepticism.

First recorded use


The oldest known extant oil paintings date from 650 AD, found in 2008 in caves in Afghanistan's Bamiyan Valley, "using walnut and poppy seed oils."

Early historic period


Though the ancient Mediterranean civilizations of Greece
Ancient Greece
Ancient Greece is a civilization belonging to a period of Greek history that lasted from the Archaic period of the 8th to 6th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and the Byzantine era. Included in Ancient Greece is the...

, Rome
Ancient Rome
Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

, and Egypt
Ancient Egypt
Ancient Egypt was an ancient civilization of Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh...

 used vegetable oils
Vegetable fats and oils
Vegetable fats and oils are lipid materials derived from plants. Physically, oils are liquid at room temperature, and fats are solid. Chemically, both fats and oils are composed of triglycerides, as contrasted with waxes which lack glycerin in their structure...

, there is little evidence to indicate their use as media
Media (arts)
In the arts, a media or medium is a material used by an artist or designer to create a work.-Architecture:In the art and science of architecture, the design and construction of buildings and interiors, infrastructure and other physical structures are created...

 in painting. Indeed, linseed oil
Linseed oil
Linseed oil, also known as flaxseed oil, is a clear to yellowish oil obtained from the dried ripe seeds of the flax plant . The oil is obtained by cold pressing, sometimes followed by solvent extraction...

 was not used as a medium because of its tendency to dry very slowly, darken, and crack, unlike mastic
Mastic (plant resin)
Mastic is a resin obtained from the mastic tree . In pharmacies and Nature shops it is called "arabic gum" and "Yemen gum". In Greece it is known as the "tears of Chios," being traditionally produced on that Greek island, and, like other natural resins is produced in "tears" or droplets...

 and wax
Wax
thumb|right|[[Cetyl palmitate]], a typical wax ester.Wax refers to a class of chemical compounds that are plastic near ambient temperatures. Characteristically, they melt above 45 °C to give a low viscosity liquid. Waxes are insoluble in water but soluble in organic, nonpolar solvents...

.

Greek writers such as Aetius Amidenus
Aëtius Amidenus
Aëtius of Amida was a Byzantine physician and medical writer, particularly distinguished by the extent of his erudition. Historians are not agreed about his exact date...

 recorded recipes involving the use of oils for drying
Drying oil
A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air. The oil hardens through a chemical reaction in which the components crosslink by the action of oxygen . Drying oils are a key component of oil paint and some varnishes...

, such as walnut
Walnut oil
Walnut oil is oil extracted from English walnuts . It is about 50% linoleic acid, an essential omega-6 fatty acid. Walnut oil is also a good source of omega-3 fatty acids which are also essential to human nutrition....

, poppy
Poppyseed oil
Poppyseed oil is an edible oil from poppy seeds . The oil has culinary and pharmaceutical uses, as well as long established uses in the making of paints, varnishes, and soaps.Poppy seeds yield 45–50% oil...

, hempseed
Hemp oil
Hempseed oil is pressed from the seed of the hemp plant irrespective of the strain of cannabis. Cold pressed, unrefined hemp oil is dark to clear light green in color, with a pleasant nutty flavor. The darker the color, the grassier the flavour....

, pine nut
Pine nut oil
Pine nut oil, also called pine seed oil or cedar nut oil, is a pressed vegetable oil, extracted from the edible seeds of several species of pine...

, castor
Castor oil
Castor oil is a vegetable oil obtained from the castor bean . Castor oil is a colorless to very pale yellow liquid with mild or no odor or taste. Its boiling point is and its density is 961 kg/m3...

, and linseed. When thickened, the oils became resinous and could be used as varnish
Varnish
Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish finishes are usually glossy but may be designed to produce satin or semi-gloss...

 to seal and protect paintings from water. Additionally, when yellow pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 was added to oil, it could be spread over tin foil
Tin foil
Tin foil, also spelled tinfoil, is a thin foil made of tin. Actual tin foil was superseded by cheaper and more durable aluminium foil after World War II, and aluminium foil is sometimes confused with "tin foil" because of its similarity to the former material.-History:Foil made from a thin leaf of...

 as a less expensive alternative to gold leaf
Gold leaf
right|thumb|250px|[[Burnishing]] gold leaf with an [[agate]] stone tool, during the water gilding processGold leaf is gold that has been hammered into extremely thin sheets and is often used for gilding. Gold leaf is available in a wide variety of karats and shades...

.

Early Christian monk
Monk
A monk is a person who practices religious asceticism, living either alone or with any number of monks, while always maintaining some degree of physical separation from those not sharing the same purpose...

s maintained these records and used the techniques in their own artworks. Theophilus Presbyter
Theophilus Presbyter
Theophilus Presbyter is the pseudonymous author or compiler ofa Latin text containing detailed descriptions of various medieval arts, a text commonly known as the Schedula diversarum artium or De diversis artibus , probably first compiled between 1100 and 1120...

, a 12th century German monk, recommended linseed oil but advocated against the use of olive oil
Olive oil
Olive oil is an oil obtained from the olive , a traditional tree crop of the Mediterranean Basin. It is commonly used in cooking, cosmetics, pharmaceuticals, and soaps and as a fuel for traditional oil lamps...

 due to its long drying time.

In the 13th century, oil was used to detail tempera paintings. In the 14th century, Cennino Cennini presented a painting technique utilizing tempera painting covered by light layers of oil.

The slow-drying properties of organic oils
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....

 were commonly known to early painters. However, the difficulty in acquiring and working the materials meant that they were rarely used (and indeed the slow drying was seen as a disadvantage). As public preference for realism increased, however, the quick-drying tempera
Tempera
Tempera, also known as egg tempera, is a permanent fast-drying painting medium consisting of colored pigment mixed with a water-soluble binder medium . Tempera also refers to the paintings done in this medium. Tempera paintings are very long lasting, and examples from the 1st centuries AD still exist...

 paints became insufficient. Flemish artists
Flemish painting
Flemish painting flourished from the early 15th century until the 17th century. Flanders delivered the leading painters in Northern Europe and attracted many promising young painters from neighbouring countries. These painters were invited to work at foreign courts and had a Europe-wide influence...

 combined tempera and oil painting during the 15th century, but by the 17th century easel painting in pure oils was common, using much the same techniques and materials found today.

Early modern era


It is commonly stated and believed (although the evidence for this is extremely questionable) that today's technique of oil painting was created circa 1410 by Jan van Eyck
Jan van Eyck
Jan van Eyck was a Flemish painter active in Bruges and considered one of the best Northern European painters of the 15th century....

. Though van Eyck was not the first to use oil paint, he was the first artist to have produced a siccative oil mixture which could be used to combine mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...

 pigments. Van Eyck’s mixture may have consisted of piled glass, calcined
Calcination
Calcination is a thermal treatment process applied to ores and other solid materials to bring about a thermal decomposition, phase transition, or removal of a volatile fraction. The calcination process normally takes place at temperatures below the melting point of the product materials...

 bones, and mineral pigments boiled in linseed oil until reaching a viscous state. Or he may have simply used Sun-thickened oils (slightly oxidized by Sun exposure). He left no written statement.

Antonello da Messina
Antonello da Messina
Antonello da Messina, properly Antonello di Giovanni di Antonio was an Italian painter from Messina, Sicily, active during the Italian Renaissance...

 later improved oil paint: he added litharge
Litharge
Litharge is one of the natural mineral forms of lead oxide, PbO. Litharge is a secondary mineral which forms from the oxidation of galena ores. It forms as coatings and encrustations with internal tetragonal crystal structure. It is dimorphous with the orthorhombic form massicot...

, or lead (II) oxide. The new mixture had a honey-like consistency and increased drying properties. This mixture was known as oglio cotto—"cooked oil."

Leonardo da Vinci
Leonardo da Vinci
Leonardo di ser Piero da Vinci was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance...

 later improved these techniques by cooking the mixture at a very low temperature and adding 5 to 10% beeswax
Beeswax
Beeswax is a natural wax produced in the bee hive of honey bees of the genus Apis. It is mainly esters of fatty acids and various long chain alcohols...

, which prevented darkening of the paint. Giorgione
Giorgione
Giorgione was a Venetian painter of the High Renaissance in Venice, whose career was cut off by his death at a little over thirty. Giorgione is known for the elusive poetic quality of his work, though only about six surviving paintings are acknowledged for certain to be his work...

, Titian
Titian
Tiziano Vecelli or Tiziano Vecellio Tiziano Vecelli or Tiziano Vecellio Tiziano Vecelli or Tiziano Vecellio (c. 1488/1490 – 27 August 1576 better known as Titian was an Italian painter, the most important member of the 16th-century Venetian school. He was born in Pieve di Cadore, near...

, and Tintoretto
Tintoretto
Tintoretto , real name Jacopo Comin, was a Venetian painter and a notable exponent of the Renaissance school. For his phenomenal energy in painting he was termed Il Furioso...

 each may have altered this recipe for their own purposes.

The use of any cooked oils or Litharge (sugar of Lead) will darken an oil painting rapidly. None of the old Masters whose work survives used these in their paintings. Both ingredients became popular in the 19th century.

Since that time, experiments to improve paint and coatings have been conducted with other oils. Modern oil paints are created from bladderpod
Bladderpod oil
Bladderpod oil is a seed oil, extracted from the seeds of the Lesquerella fendleri and other species of genus Lesquerella, Native to the plains and mesas of southwestern United States, eastward to Kansas and southward into northern Mexico. Bladderpod oil is rich in lesquerolic acid which is a...

, ironweed
Vernonia
Vernonia is a genus of about 1000 species of forbs and shrubs in the family Asteraceae. Some species are known as Ironweed. Some species are edible and of economic value. They are known for having intense purple flowers. The genus is named for English botanist William Vernon. There are numerous...

, calendula
Calendula
Calendula , pot marigold, is a genus of about 12–20 species of annual or perennial herbaceous plants in the daisy family Asteraceae, native to the area from Macaronesia east through the Mediterranean region to Iran...

 and sandmat, plants used to increase the resistance or to reduce the drying time.

Paint tube



The paint tube was invented in 1841, superseding pig bladder
Pig bladder
Pig bladder is the bladder of a domestic pig, similar to the human urinary bladder. Today, this hollow organ has various applications in medicine, and in traditional cuisines and customs...

s and glass syringes as the primary tool of paint transport. Artists, or their assistants, previously ground each pigment by hand, carefully mixing the binding oil in the proper proportions. Paints could now be produced in bulk and sold in tin tubes with a cap. The cap could be screwed back on and the paints preserved for future use, providing flexibility and efficiency to painting outdoors. The manufactured paints had a balanced consistency that the artist could thin with oil, turpentine, or other mediums.

Paint in tubes also changed the way some artists approached painting. The artist Pierre-Auguste Renoir
Renoir
-People with the surname Renoir :* Pierre-Auguste Renoir , French painter* Pierre Renoir , French actor and son of Pierre-Auguste Renoir* Jean Renoir , French film director and son of Pierre-Auguste Renoir...

 said, “Without tubes of paint, there would have been no Impressionism
Impressionism
Impressionism was a 19th-century art movement that originated with a group of Paris-based artists whose independent exhibitions brought them to prominence during the 1870s and 1880s...

.” For the Impressionists, tubed paints offered an easily accessible variety of colors for their plein air
En plein air
En plein air is a French expression which means "in the open air", and is particularly used to describe the act of painting outdoors.Artists have long painted outdoors, but in the mid-19th century working in natural light became particularly important to the Barbizon school and Impressionism...

 palettes, motivating them to make spontaneous color choices. With greater quantities of preserved paint, they were able to apply paint more thickly.

Carrier



Characteristics


Traditional oil paints require an oil that will gradually harden, forming a stable, impermeable film. Such oils are called siccative, or drying
Drying oil
A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air. The oil hardens through a chemical reaction in which the components crosslink by the action of oxygen . Drying oils are a key component of oil paint and some varnishes...

, oils, and are characterized by high levels of polyunsaturated fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...

s. One common measure of the siccative property of oils is iodine number
Iodine number
The iodine value in chemistry is the mass of iodine in grams that is consumed by 100 grams of a chemical substance. An iodine solution is yellow/brown in color and any chemical group in the substance that reacts with iodine will make the color disappear at a precise concentration...

, the number of grams of iodine
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....

 one hundred grams of oil can absorb. Oils with an iodine number greater than 130 are considered drying, those with an iodine number of 115-130 are semi-drying, and those with an iodine number of less than 115 are non-drying. Linseed oil, the most prevalent vehicle for artists' oil paints, is a drying oil.

When exposed to air, oils do not undergo the same evaporative
Evaporation
Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid....

 process that water does. Instead, they polymer
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

ise into a dry semisolid. This rate of process can be very slow, depending on the oil.

The advantage of the slow-drying quality of oil paint is that an artist can develop a painting leisurely. Earlier media such as egg tempera dried quickly, which prevented the artist from making changes or corrections. With oil-based paints, revising was comparatively easy. The disadvantage is that a painting might take months or years to finish, which might disappoint an anxious patron. Oil paints also blend well with each other, making subtle variations of color possible as well as more easily creating details of light and shadow. Oil paints can be diluted with turpentine or other thinning agents which allowed an artist to build a painting in layers, however, such agents are highly flammable and the danger of a studio fire was always present.

Sources


The earliest and still most commonly used vehicle is linseed oil
Linseed oil
Linseed oil, also known as flaxseed oil, is a clear to yellowish oil obtained from the dried ripe seeds of the flax plant . The oil is obtained by cold pressing, sometimes followed by solvent extraction...

, pressed from the seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...

 of the flax
Flax
Flax is a member of the genus Linum in the family Linaceae. It is native to the region extending from the eastern Mediterranean to India and was probably first domesticated in the Fertile Crescent...

 plant. Modern processes use heat or steam in order to produce refined varieties of oil, which contain fewer impurities, but cold-pressed oils are still the favorite of many artists. Other vegetable oils such as Hemp
Hemp oil
Hempseed oil is pressed from the seed of the hemp plant irrespective of the strain of cannabis. Cold pressed, unrefined hemp oil is dark to clear light green in color, with a pleasant nutty flavor. The darker the color, the grassier the flavour....

, poppy seed
Poppyseed oil
Poppyseed oil is an edible oil from poppy seeds . The oil has culinary and pharmaceutical uses, as well as long established uses in the making of paints, varnishes, and soaps.Poppy seeds yield 45–50% oil...

, walnut
Walnut oil
Walnut oil is oil extracted from English walnuts . It is about 50% linoleic acid, an essential omega-6 fatty acid. Walnut oil is also a good source of omega-3 fatty acids which are also essential to human nutrition....

, sunflower
Sunflower oil
Sunflower oil is the non-volatile oil expressed from sunflower seeds. Sunflower oil is commonly used in food as a frying oil, and in cosmetic formulations as an emollient. Sunflower oil was first industrially produced in 1835 in the Russian Empire.- Composition :Sunflower oil is mainly a...

, safflower, and soybean oil
Soybean oil
Soybean oil is a vegetable oil extracted from the seeds of the soybean . It is one of the most widely consumed cooking oils. As a drying oil, processed soybean oil is also used as a base for printing inks and oil paints...

s may be used as alternatives to linseed oil for a variety of reasons. For example, safflower and poppy oils are paler than linseed oil and allow for more vibrant whites straight from the tube.

Extraction methods and processing


Once the oil is extracted additive
Oil additive
Oil additives are chemical compounds that improve the lubricant performance of base oil . By utilizing the same base stock, many different oils can be manufactured, each with its distinctive properties. Additives comprise up to 5% by weight of some oils.Nearly all commercial motor oils contain...

s are sometimes used to modify its chemical properties. In this way the paint can be made to dry more quickly if that is desired, or to have varying levels of gloss
Gloss
A gloss is a brief notation of the meaning of a word or wording in a text. It may be in the language of the text, or in the reader's language if that is different....

. Modern oils paints can, therefore, have complex chemical structures; for example, affecting resistance to UV
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

 or giving a suede
Suede
Suede is a type of leather with a napped finish, commonly used for jackets, shoes, shirts, purses, furniture and other items. The term comes from the French "gants de Suède", which literally means "gloves of Sweden"....

 like appearance.

Pigment



The color of oil paint derives from the small particles mixed with the carrier. Common pigment types include mineral salts such as white oxides: lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...

, now most often replaced by less toxic zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

 and titanium
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....

, and the red to yellow cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...

 pigments. Another class consists of earth types
Clay earth pigment
Clay earth pigments are naturally occurring minerals, principally iron oxides, that have been used since prehistoric times as pigments. The primary types are*ochre*sienna*umber...

, e.g. sienna
Sienna
Sienna is a form of limonite clay most famous in the production of oil paint pigments. Its yellow-brown colour comes from ferric oxides contained within...

 or umber
Umber
Umber is a natural brown clay pigment which contains iron and manganese oxides. The color becomes more intense when calcined , and the resulting pigment is called burnt umber. Its name derives from the Latin word umbra and was originally extracted in Umbria, a mountainous region of central Italy,...

. Synthetic
Chemical synthesis
In chemistry, chemical synthesis is purposeful execution of chemical reactions to get a product, or several products. This happens by physical and chemical manipulations usually involving one or more reactions...

 pigments are also now available. Natural pigments have the advantage of being well understood through centuries of use but synthetics have greatly increased the spectrum available, and many are tested well for their lightfastness.

Toxicity


Many of the historical pigments were dangerous, and many pigments still in popular use today are highly toxic. Many toxic pigments, such as Paris green
Paris Green
Paris Green is an inorganic compound more precisely known as copper acetoarsenite. It is a highly toxic emerald-green crystalline powder that has been used as a rodenticide and insecticide, and also as a pigment, despite its toxicity. It is also used as a blue colorant for fireworks...

 (copper(II) acetoarsenite) and orpiment (arsenic
Arsenic
Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...

 sulfide), to name only two, have fallen from use. Some pigments still in use are toxic to some degree, however. Many of the reds and yellows are produced using cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...

, and vermilion
Vermilion
Vermilion is an opaque orangish red pigment, similar to scarlet. As a naturally occurring mineral pigment, it is known as cinnabar, and was in use around the world before the Common Era began. Most naturally produced vermilion comes from cinnabar mined in China, and vermilion is nowadays commonly...

 red uses natural or synthetic mercuric sulfide or cinnabar
Cinnabar
Cinnabar or cinnabarite , is the common ore of mercury.-Word origin:The name comes from κινναβαρι , a Greek word most likely applied by Theophrastus to several distinct substances...

. Flake white and Cremnitz white are made with basic lead carbonate
Lead carbonate
Lead carbonate is the chemical compound PbCO3. It is prepared industrially from lead acetate and carbon dioxide.It occurs naturally as the mineral cerussite.-Basic lead carbonates:...

. The cobalt colors, including cobalt blue
Cobalt blue
Cobalt blue is a cool, slightly desaturated blue color, historically made using cobalt salts of alumina. It is used in certain ceramics and painting; the different cobalt pigment smalt, based on silica, is more often used directly in tinted transparent glasses...

 and cerulean blue, are made with cobalt
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

 compounds. Some varieties of cobalt violet are made with cobalt arsenate.

See also

  • Acrylic paint
    Acrylic paint
    Acrylic paint is fast drying paint containing pigment suspension in acrylic polymer emulsion. Acrylic paints can be diluted with water, but become water-resistant when dry...

  • Acrylic painting techniques
    Acrylic painting techniques
    Acrylic painting techniques are different styles of manipulating and working with polymer-based acrylic paints. Acrylics differ from oil paints in that they have shorter drying times and are soluble in water. These types of paint eliminate the need for turpentine and gesso, and can be applied...

  • Drying oil
    Drying oil
    A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air. The oil hardens through a chemical reaction in which the components crosslink by the action of oxygen . Drying oils are a key component of oil paint and some varnishes...

  • Egg tempera
  • Oil painting
    Oil painting
    Oil painting is the process of painting with pigments that are bound with a medium of drying oil—especially in early modern Europe, linseed oil. Often an oil such as linseed was boiled with a resin such as pine resin or even frankincense; these were called 'varnishes' and were prized for their body...

  • Semi-drying oil
    Semi-drying oil
    A semi-drying oil is an oil which partially hardens when it is exposed to air. This is as opposed to a to drying oil, which hardens completely, or a non-drying oil, which does not harden at all. Oils with an iodine number of 115-130 are considered semi-drying.-Examples of semi-drying oils:*Corn...

  • Watercolor