(Excerpts from ART HARDWARE: The Definitive Guide to Artists’ Materials, by Steven Saitzyk © 1987 revised 1998)
Historians place the origins of oil painting just before Leif Ericson reached the shores of North America and the dawn of the Middle Ages in Europe. It appears to have been in continuous use for some 1100 years. No other paint medium commonly used today reaches that far back in time. If there is an essence that all visual arts could be distilled to, it would be oil painting. All media today are judged in the light of oil painting. Arguments seem to vaporize at the first sight of a La Tour, Caravaggio, Rembrant, Monet, or Van Gogh. The is a quality to oil painting that transends the medium itself. Sure, oils yellow over time affecting the colors, and yes, they can develop cracking when improperly applied, but which western medium does not have inherent problems? Some have even more, but none have survived history as this meduim has. The popularity of oil painting has risen and fallen, its technology ignored and in some cases forgotten forever, but it remains the standard for all painters.
The essence of this medium is the oil. It provides not only the vehicle to move and bind the pigments to a surface; it is what gives it its luminosity, depth, versatility, and unsurpassed brilliance. If you understand the nature of the oil, it is an easy mastered medium. All those centuries ago it was discovered that there are specific vegetable oils that dry, harden and yet remain clear and, to some degree, flexible. When you mix in dry pigments, it would bind them to a large variety of surfaces. But it takes time for this to happen, often five to ten days and longer in damp and humid climates such as the Netherlands and Italy where oil painting first became popular. Around the time Chaucer published the Canterbury Tales, 1390, it was discovered that if you mixed a bit of lead or zinc pigment into the oil it would accelerate the drying time to only one to three days. Though they did not know why it worked, it made oil paint a viable and desirable medium and it spread quickly. But, today we do know the chemistry involved in the process. Drying oils dry because they chemically react with oxygen in the air and form a new substance that hardens. They do not dry through evaporation. Water, mineral spirits, turpentine, alcohols, and other solvents, in their pure form, evaporate without a trace. If a drying oil evaporated, there would be no oil paint film. What would be left behind would be dry pigments and a few additives that would dust off the surface. Zinc and lead act as catalysts, assisting the chemical reaction, known as oxidation, and speeding it up. This important bit of knowledge regarding the chemistry of painting is still missed today, evidenced by some major contemporary artists experimenting with making their own paints and using a non-drying oil such as mineral oil or sunflower oil and finding that their paints and paintings never dry and harden.
Even though the discovery of the catalytic nature of zinc and lead was a major advancement for its time, oil painting still had technological issues that need to be addressed to make it a universally acceptable medium. Glazing involves heavily thinning the paint with oil so the previous paint film can be seen through the top layer. It was a difficult process because the glaze would often continue to flow or migrate beyond where you put it. This was solved during the latter part of the Renaissance with the introduction of the plant resins damar and mastic. It was discovered that such resins would thicken the paint film and enable it to stay where it was put. It also permitted a quicker application of successive layers, forming a thicker and more expressive painting. This set the ground for the development of the alla prima (one sitting) style of painting. This resinous oil paint produced a paint film of great durability and was preferred by many of the Old Masters, like Titian and Rubens. Unfortunately for us, many of their specific recipes for making resin‑oils and their use are now lost. If the artist did not have an apprentice the information was often taken to the grave. When artists did keep journals they often only wrote down their failures so they would not repeat them and memorized their successes to keep them secret. We do know today how these resins work, though we may not be able to duplicate their exact formula. Resins like damar and mastic dissolve in turpentine much like salt in water. When the turpentine evaporates, crystals of damar and mastic reform just as salt crystals take shape when the water is gone. By dissolving the resin in turpentine you can then mix the dissolved resin into the drying oil. Since turpentine evaporates much faster than a drying oil oxidizes the paint film seems to harden as the solvent evaporates. What is happening is as the turpentine evaporates the resin recrystalizes within the paint film giving it body until the drying oil has a chance to chemically react with the air and harden permanently on its own. These two discoveries became the foundation for all oil painting.
Before the period of industrialization during the nineteenth century, artists had a very limited palette consisting largely of earth colors. The primary colors made of reds like Dragon’s Blood, yellows like orpiment, and blues like blue verditer were relatively impermanent. One exception was the blue of lapis lazuli, which is permanent, but cost more than gold by weight. The invention modern of chemistry, during the early 1800’s, led to a great many by-products. One of them was the modern palette, a spectrum of new pigments the likes of which no one had seen before. It made Impressionism and the Luminist schools possible. Pigments such as cobalt blue, chromium oxide green, cadmium yellow, chrome yellow, barium yellow, zinc yellow, cerulean blue, ultramarine blue (synthetic), zinc white, viridian, and cobalt violet were stable and relatively affordable.
It was the time of invention and along with photography, the bicycle, the revolver pistol came the collapsible tin tube, patented in England by the American artist, John Goffe Rand, in 1841. This was followed in 1859 with the screw cap by the French manufacturer Lefranc (which later became the art materials company know today as Lefranc & Bourgeois). This was no small achievement when you consider that before this time oil painting was considered a studio art, because it was too expensive and difficult to take paints on location to work outdoors. What was available were pig bladders or syringes to contain the paint. The bladders, though cheaper, dried out quickly, and the syringes were very expensive and often clogged. Now artist could paint what they saw or felt in the moment they experienced it in the native surroundings instead of in a studio from watercolor sketches or memory.
A culture of Colormen ensued. William Winsor and Henry Charles Newton formed Winsor & Newton in 1832 in England (www.winsornewton.com), the Lefranc brothers formed a company in 1836, Jacques Blockx in Belgium becomes the founder of Blockx in 1865, and Hermann Schmincke and Josef Horadam began H. Schmincke & Co. in Germany in 1881. They evolved in much the same way as did Sennelier in France during 1887, from a direct working relationship with artists such as Cezanne and Monet, who would come to the chemist, Gustave Sennelier’s Maison to paint in his gardens, and sometimes test colors he made at their request. Artists were liberated from the difficult and often overwhelming task and expense of manufacturer and testing all their materials.
The development of prepackaged oil paints did not come without some sacrifices in quality. To utilize the new tin tubes and impart a reasonable shelf-life to the paint it contained, oil paints had to be reformulated. The more desirable resin‑oil paints with their brilliance and where each color was formulated to dry at a similar rate in order to allow for proper interlocking of paint films, had to be, for the most part, abandoned in favor of a resin-free oil paint. The resin would harden in the tube after a few days and the paint would become unusable. With their higher oil content, the new paints tended to yellow more. The increased oil content also meant a more fluid consistency, which was often offset by the addition of a wax that in turn resulted in an ever so slight reduction in brilliance and clarity. Because of the wide variation of drying times among pigments, chemical driers were needed to make up for the loss of resin, however, they can be more hazardous to a paint film and inconsistent in their behavior. Over the decades manufacturers of the highest quality paints have sought to develop recipes using modern chemistry that would impart that “Old Masters” quality to packaged paints.
The way the artist mitigates these small but significant issues is by the use of media. There is the now common phrase that tube paints should always be “let down.” This means that all tube, canned, or packaged paints should never be used directly out of the package without at least some media. Using media with paint is called letting it down. It is preparing the paint to be used. The artist risks poor adhesion, cracking, and shriveling if this practice is ignored.
During the early to mid nineteen hundreds there was another chemical revolution involving synthetics and derivatives from petroleum products that greatly expanded the artist palette once again. These new pigments, commonly used today in paints, inks, packaging, and even in foods, when non-toxic, have a high tinting strength, and tend to be transparent. Many appear to have similar surface colors as the mineral pigments from the 1800’s, but when mixed with white or other colors, the results are completely different tints, colors, or shades. These new pigments tend not to gray down when mixed and instead result in new intense, if not unworldly looking colors, not unlike those found in a modern cityscape with brightly colored automobiles, billboard signs, neon lights and mercury vapor lamps illuminating the streets. Colors made from mineral pigments like the reds, yellow, and oranges made from cadmium, the blues and violets made from cobalt, and light blues through dark browns made from manganese, would gray when mixed with other colors or easily lighten when white was added. This is perfect for figurative and landscape painting where the noon days sun might bleach out the desert colors or human features, or where the reflected natural light grays out in the distance. One great advantage to many of these new synthetic pigments is that a little color goes along way and the pigment itself is relatively inexpensive. The disadvantage is that many of these new pigments are dye-pigment that can stain or bleed into adjacent painted areas, brushes, and palettes.
Today manufacturers continue to experiment with different pigments, methods of grinding, and the aging of paint. They try new drying oils or synthetic resins like alkyds, and in some cases attempt to reconstruct the old resin‑oil paint with modern technology. But they are ever mindful not to loose the appearance, the physicality, the aesthetic that oil paint possesses like no other medium, and which had resonated in the heart of every painter.
(Excerpts from ART HARDWARE: The Definitive Guide to Artists’Materials, by Steven Saitzyk © 1987 revised 1998)