Aniline is mostly used as preparation of methylene diphenyl diisocyanate (MDI), but it is also used in herbicides, rubber and dyes and pigments. Mauveine, also known as aniline purple and Perkin’s mauve, was the first synthetic organic dye. See my separate post about Mauveine.

Aniline dyes are used a lot in the woodworking and leather professions, sometimes in place of stains. They usually come in a powder form and are mixed with water, alcohol or petroleum solvents (but are sometimes premixed – see image on the left). The biggest difference between stains and dyes is the color – many stains look muddy, sort of like looking through a window with the screen on. Remove the screen and you get an idea of the clear colors produced by aniline dyes.

The reason is simple. Most stains leave tiny colored particles (pigments) on the surface of the wood. But dyes penetrate the wood fibers. This emphasizes the figure of the wood instead of partially obscuring it.

Aniline dyes also color the wood more evenly than pigmented stains. Unlike stains that concentrate in the areas of the wood that have large pores (like end grain), dyes penetrate all parts equally.

Another nice thing about aniline dyes is the wide range of colors. There are even bright primary colors, like what you might want to use on kids’ projects.

You can read up on Aniline Dyes Woodworking Techniques at woodstore.net. 

Sources: wikipedia, woodworkingtips.com, woodstore.net

Casein paint is derived from milk casein, a protein that is found in milk and often times used as a binding agent in foods. There are two main types of casein, edible and technical. Edible casein is widely used in medicines and foods, both as a binder and for nutritional value. Technical casein is used lots of products, including paints, cosmetics, adhesives and much more. Paint made from casein is fast-drying and water-soluble. It generally has a glue-like consistency, but can be thinned with water to the degree that fits a particular artist’s style and desired result. It can be used on canvas panels, illustration boards, paper, wood and masonite. It generally dries to a matte finish. However, because the dried paint is inflexible and brittle it is not usually used on flexible surfaces such as canvas. Casein was widely used by commercial illustrators until the late 1960s when, with the advent of acrylic paint, casein became less popular. 

Visually casein paint can resemble oil painting more than most other water based paints, and works well as an underpainting. It has been used since ancient Egyptian times as a form of tempera paint and is still used today. Artists value it because, unlike gouache, it dries to an even consistency making it ideal for murals. 

You can quickly make your own casein paint. Simply take some skim milk cottage cheese and wash off any of the milky fluids. The lumps of casein left behind are then dissolved by adding, in a pot, water and some ammonia. The ammonia should be preferably in the form of ammonium carbonate. Stir the mixture while it warms until it begins to froth and the lumps dissolve. Do not boil but keep simmering and continue to stir until the frothing stops. Let the syrup cool and use that as your medium.

Santa Clara Pueblo artist Pablita Velarde created a series of more than 70 paintings of everyday Native American life in New Mexico for Bandelier National Monument between 1937 and 1943, painted mostly on masonite using casein paints. The photo above is titled “Three Women Grinding Corn” and it is from 1940.

sources: wisegeek.com, Wikipedia

The paint is made by binding pigment in an egg medium. Egg yolk dries quickly and adheres firmly. Tempera was traditionally created by hand grinding dry powdered pigments into egg yolk which acts as the primary binding agent or medium. Other materials such as honey, water, milk and plant gums were often included as well. It dries rapidly. The colors, which are painted over each other, resemble a pastel when unvarnished and display deeper colors when varnished. The paint is normally applied in thin, semi-opaque or transparent layers. When it dries it produces a smooth matte finish. True tempera paintings are quite permanent, the colors do not change over time, whereas oil paintings darken, yellow and become transparent with age.

Italy, Greece and Russia were the major centers of tempera painting. It was, for the most part, replaced by oil painting in the 1500s, though it is still popular today in Greece and Russia. Throughout the 19th and 20th centuries there were intermittent revivals of tempera technique in Western art.

Making tempera paint is very easy: 

Place a small amount of the pigment paste onto a palette, dish or bowl.

Add about an equal volume of the egg medium and mix well making sure there are no lumps of pigment. Some pigments require slightly more egg medium, some require less.

Add distilled water (usually less than a teaspoon per egg yolk), trial and error will dictate just how much water is required. 

Most often only the contents of the yolk are used. The white of the egg and the membrane of the yolk are discarded. You can isolate the yolk and dry the membrane slightly by rolling it on a paper towel. Then pick up the yolk gently by the membrane, dangle it over a receptacle and puncture the membrane with a knife or other sharp instrument to drain off the liquid inside.

If the paint contains too much yolk, the paint will look greasy and clumpy; too much water makes it run. So, it’s important to adjust the amount of water and yolk to achieve a consistent paint. As tempera dries, you will probably need add more water to preserve the consistency and to balance the thickening of the yolk on contact with air.

Different preparations use the egg white or the whole egg for different effect. Also other additives such as oil and wax emulsions can modify the medium. Adding oil for instance in no more than a 1:1 ratio with the egg yolk by volume will produce a water soluble medium with many of the color effects of oil paint, although it cannot be painted thickly.

Her list of colors includes (along with comments from her):

RED OCHRE – Hematite
Red stone, pink cliffs, dark pebble with iron at its heart. 

YELLOW OCHRE – Limonite, Goethite 
Flames in sunlight.  Wind-polished metallic brown geodes filled with ochre. 

GREEN CLAY – Glauconite, Celadonite, Volkonskoite 
Leaves, caterpillars, lichens.  Bubbles in pondwater, shadows in the deep forest. Embracing Earth, speaking to the land in small secret places. 

WHITE EARTH – Chalk, Kaolin 
Egg, bone, shell, flint.  Old turtle shell full of quartz pebbles. Light at the edge of the forest. 
Revealing what is hidden under tangled roots.  Truth and doubts. 

BLUE OCHRE – Vivianite 
Mussel shell, fossil mammoth ivory, fossil snail filled with blue dust.

BLACK EARTH – Charcoal, Charred Bone, Black Shale, Magnetite, Mn Oxides 
Burned roots, petrified wood, iron meteorite, desert varnish, tar-filled geode in oily clay. 

PURPLE OCHRE – Purpurite, Mn-rich Clay, Metallic Hematite, Cuprite 
Earthsmoke drifting from fallen leaves, delicate cup fungi sprouting on burned ground. 

COPPER EARTH – Malachite, Dioptase, Gaspeite (Ni, not Cu) 
Ancient bronze, malachite on a boulder, moth eyes, foxfire. 

TURQUOISE – Azurite, Chrysocolla, Turquoise 
Windy heaven, round sky-colored pebble, mountain bluebird in clouds. 

PINK EARTH – Pipestone, Pink Clay 
Wild plum flowers falling on rose quartz, tiny white feather in a rhodochrosite snail fossil. Compassion, heart of the Earth Goddess, comfort and return to the source. 

source: mineralarts.com

• adhesion and related properties like resistance to blistering, cracking and peeling

• other key resistance properties like resistance to scrubbing, chalking and fading

• application properties like flow, leveling and film build, and gloss development

With no pigment present, most binders would dry to form a clear, glossy film; some binders are used without pigments to make clear finishes and varnishes. Binders include synthetic or natural resins such as acrylics, polyurethanes, polyesters, melamine resins, epoxy, or oils.

Binders can be categorized according to drying or curing mechanism. The four most common are:

simple solvent evaporation
oxidative crosslinking
catalyzed polymerization
coalescence

Drying and curing are actually two different processes. Drying generally refers to evaporation of the liquid (called the vehicle) which carries the pigment, whereas curing refers to polymerization of the binder. (The term “vehicle” is often used inconsistently, sometimes to refer to the solvent and sometimes to refer to the binder.) Depending on chemistry and composition, any particular paint may undergo either or both processes. Thus, there are paints that dry only, those that dry then cure and those that do not depend on drying for curing.

Solvent is the liquid in paint that suspends the pigment and resins and transports them from the paint brush to the painted surface. The solvent then evaporates and leaves the paint film behind. Solvents in paint can be water (for latex paint) or mineral spirits (for oil based alkyd paint). The less solvent in the paint the higher the quality and the better the coverage.

Water is the main vehicle for water-based paints.

Solvent-based, sometimes called oil-based, paints can have various combinations of solvents as the vehicle, including aliphatics, aromatics, alcohols, and ketones. These include organic solvents such as petroleum distillate, esters, glycol ethers, and the like. Sometimes volatile low-molecular weight synthetic resins also serve as diluents. 

source: wikipedia, about.com, paintquality.com

Perkins patented the dye and opened a dyeworks in London to mass produce it. It was originally manufactured under the name “aniline purple.” The name “mauve” was given to it in England in early 1959 (from the French word malva for the mallow flower) and chemists later called it mauveine. It became very fashionable in 1862 when Queen Victoria appeared at the Royal Exhibition in a mauve silk gown. Perkins made a fortune and gave birth to the synthetic chemical industry.

The gentleman on the left (Professor Charles Rees) is wearing a tie dyed with an original sample of mauveine and holding the Royal Society Of Chemistry journal named after Perkins.

1 egg yolk
1 tsp gum arabic
1/2 cup honey
1/2 tsp lamp black (make by holding a plate over a lit candle)

To make homemade ink that is black mix the honey with an egg yolk. Then add gum Arabic to the mix. Take a plate and hold it above a lighted candle to make a black slick on the bottom of the plate. Mix a little of the honey mixture on the plate to collect the lamp black and then mix what you have collected into the rest of the honey mixture. To use this mixture as an ink mix it with a little water before you use it. Store it in a tightly closed jar.

You can make brown ink just as easily:

1/2 cup boiling water
4-5 teabags (or 4 tsp of loose tea)
1 tsp gum arabic

Pour boiling water over the tea bags in a large bowl and add gum arabic. Steep for 15 minutes. Squeeze the teabags to extract as much tannic acid as possible. Strain and allow to cool before bottling. 

source: makestuff.com

A lake pigment is a pigment manufactured combining an organic dye with an inert binder, usually a metallic salt. Many lake pigments are fugitive because the dyes involved are unstable when exposed to light. The metallic salt or binder must be very inert and insoluble in the vehicle, it must be white or very neutral and it must have low tinting strength so that the dye itself determines which wavelengths or light are absorbed and reflected. In ancient times chalk, white clay and crushed bones were used as the salts (all are sources of calcium carbonate and/or calcium phosphate). Today the salts most commonly used include barium sulfate, calcium sulfate, aluminum hydroxide and aluminum oxide, all of which can be produced cheaply. 

Above you can see an example of some flowers illustrated by using lake pigments.

Lake pigments have a long history in the arts. Some have been produced for thousands of years and were often traded over long distances. A few of the most well known are:

Indigo Lake, which was originally produced from the leaves of woad. It was used in ancient Egypt. In the late Middle Ages Indigo was imported from India and used as a substitute for woad. Today the dark blue dye once produced from woad is know as Indigo. Both the dye and the pigment are fugitive.

Rose Madder Lake, which was originally produced from the root of the madder plant. It too is fugitive when exposed to light and has mostly been replaced by synthetic materials.

Carmine Lake (or Crimson Lake), which was originally produced from the cochineal insect, native to Central and South America. When the Spanish conquered the Aztec Empire they discovered this unknown crimson color. After silver, cochineal became their most valuable export back to the Old World and the secret of its production was guarded for centuries.

Most of the lake pigments are now produced more cheaply from synthetic sources, although some artisans still prefer the natural versions.

source: wikipedia

Linseed oil is a clear, golden yellowish, brown or amber drying oil (meaning that it thickens and becomes hard on exposure to air) derived from the dried ripe seeds of the flax plant. It is also know as Flax seed oil or flax oil. It is obtained by pressing the seeds and sometimes by then using solvent (or liquid-liquid) extraction. Cold pressed oil, obtained without solvent extraction, is marketed as flaxseed oil. 

The cool painting on the left is described by the artist as, “An ancient bottle of linseed oil – covered in dust and full of sediment- which has been sitting in the same place on a shelf in my grandfathers old garage for at least fifty years.” The painting is by Neil Nelson.

Linseed oil is the most commonly used carrier (or vehicle) in oil paint and printing inks. It helps to make the paints more fluid, transparent and glossy. There are several different varieties, including Cold Pressed, alkali refined, sun Bleached, sun thickened and polymerised. Oil paints today are made by mixing dry powder pigments with selected refined linseed oil to a stiff paste consistency and grinding it by strong friction in steel roller mills. 

Linseed oil is also used as a wood finish, in the production of linoleum and a nutritional supplement.

sources: wikipedia, Encyclopedia Britannica

To work as a good pigment a material should be stable in solid form at ambient temperatures and it should have a high tinting strength relative to the materials it colors. Pigments that are not permanent are called “fugitive.” Fugitive pigments fade over time and/or with exposure to light.

Today pigments are used for coloring paint, ink, plastic, cosmetics and even food. Most pigments used in visual arts are dry and ground into a fine powder. (To the left you can see an example of natural ultramarine pigment in a powdered form.)This powder is then added to a vehicle (sometimes called a matrix), a relatively neutral or colorless material that acts as a binder.

There is a subtle difference between a pigment and a dye. A pigment is insoluble in the vehicle, meaning that it is suspended. A dye is either a liquid itself or is soluble in the vehicle, resulting in a solution. 

Naturally occurring pigments have been used as colorants since prehistoric times. Pigments and paint grinding equipment believed to be between 350,000 and 400,000 years old (!) have been discovered in Zambia. The earliest known pigments were natural minerals such as Red Ochre and Yellow Ochre. Before the Industrial Revolution most pigments were from earth, mineral or biological origins. Pigments created from unusual sources, such as animal waste, insects, mollusks and other things were often traded over long distances. Some colors were simply too costly to create and thus were very rare.

Spain’s conquest of the New World in the 16th century introduced new pigments and colors to inhabitants on both sides of the Atlantic Ocean. The Industrial Revolution brought a huge expansion in the range of synthetic pigments. The development of chemical pigments and dyes has radically changed and enlarged the selection of pigments available in today’s world.

sources: wikipedia