Black oil is made by cooking linseed oil with white lead or Litharge.
During painting, the colors were thinned with "black oil". This paste was made mixing a gum arabic (acacia tree sap) solution into the same varnish. Yellow varnish was made by melting dammar crystals (a tree resin) in hot linseed oil, mixing them with a water-in-oil emulsion paste. One popular medium, known as Maroger's, was made by grinding pigments with "yellow varnish". As more artists started using it in their paintings, this new enamel-like appearance changed the way paintings looked from that moment on. Mixing a small amount of this oil with prepared paints could give paintings an enamel-like appearance, without the yellowing of normal linseed oil. While it was no longer suitable to grind pigments with to make paint, it was discovered to have superior paint leveling properties.
This heating process changed the nature of the oil. It was probably discovered by accidentally leaving the oil out to bake in the sun for many hours. Perhaps the very first true painting medium discovered, still in use today, is sun-thickened linseed oil, pressed from flaxseed.
With the development of reliable oil-based paint mixtures, artists were also experimenting with painting mediums which could be added to their crude paints and which would give them better handling and finish characteristics. Some of these materials proved to be highly toxic to the artists and assistants who handled them, and this knowledge, too, was slowly handed down by word of mouth. Artists experimented with pigments and binders for centuries in search of the perfect combinations of materials which would give the paint good brushing/handling characteristics, glossy finish, predictable drying times and hopefully, longevity. In the days of custom hand-made paints, a great artist could be known not only by his distinctive painting technique or style, but also by the fact that his paint formulas would impart a unique look to his work that no other artists could easily emulate. Paint formulas were guarded secrets and often passed from master artist to apprentice. If one wanted to be a painter, one therefore had to become a chemist as well. While many other types of plant oils have been tried over the centuries and found to be suitable to the task, the oil extracted from flax seeds, known as linseed oil, soon became recognized as a superior binder and vehicle for all types of pigments and gave rise to what are known as oil paints.īecause there were no paint manufacturers in ancient times, artists had to make all their own paints. Eventually some of these early artists discovered that oils derived from the crushed seeds of certain plants could provide an excellent binder/vehicle component which would not only impart fluidity to their pigment mixes, but also a hard and durable finish when thoroughly dry. Many of these substances proved to have unsuitable aging or durability characteristics and were therefore replaced as different materials were discovered to work better. So artists experimented with different substances - animal fat, tree saps and plant resins, for example, to try to obtain a binder, or glue which would give the paint more adhesion and durability. Unless protected form the elements, as in a cave, these crude paints would soon be erased. Once applied, the water would evaporate and leave the pigment on the surface. The earliest known pigments were earth colors, literally made from colors found in the earth, ground into a fine powder, and then mixed with a liquid vehicle, such as water.
0 kommentar(er)
