Types of soil for oil painting, their properties and methods of preparation Automatic translate
GLUE SOILS
Glued soils strongly absorb oil from paints, and the painting on them has a slightly matte surface. Glue soil is easy to prepare, it does not require long-term drying.
In a warm 5-7% glue solution, gradually, with continuous stirring, fill the filler to obtain a composition similar to liquid sour cream. This composition is applied to a glued canvas with a wide brush or a flute in two layers. After applying the first layer, it is dried for at least 12 hours, lightly polished with pumice or sandpaper. Then dust and fibers are brushed off and a second layer is applied. In some cases, a liquid solution of 4% adhesive is applied. Excess glue leads to cracking of the soil and the paint layer; from an insufficient amount of glue, the soils become loose and absorb too much oil, thereby violating the bond strength and causing a strong dying of paints.
OIL SOILS
Oil soil consists of dry pigments worn on drying vegetable oil. As a binder, it is best to use linseed oil. For the elasticity of oily soils, a small amount of castor oil is added (per 10 grams of linseed oil - 1 gram of castor oil). For the preparation of oil soils, pre-prepared undiluted oil paints are most often used, which are applied by carefully leveling with a spatula or spatula, and then with a flange.
Oil-based canvases require long-term drying - about two years. Oil soils have a glossy surface, do not absorb oil from paints, which makes the connection between the soil and the paint layer unstable, especially with multilayer pasty painting. The paint layer in the works painted on canvas with oil soil, not getting the necessary adhesion to the glossy surface, begins to peel off over time. Some paintings by Russian artists of the second half of the 19th century, such as I. Repin, M. Nesterov, V. Polenov and others, have similar destructions.
EMULSION SOILS
Emulsion soil is prepared on emulsions from glue and oil, where the oil in the form of fine particles, in suspension, is in a liquid adhesive solution. According to their properties, emulsion soils are between oil and adhesive: if there is little oil in the emulsion soil, it is closer to the adhesive, if a lot - to the oil. Many artists who use this type of soil for painting, with each subsequent layer increase the oil content in the soil composition. This provides a gradual transition from the sizing layer to the oil paint layer and contributes to good adhesion of the canvas to the ground and soil to the paint layer.
The most important condition on which the quality of the soil depends is the uniformity of the emulsion. When preparing glue-oil emulsion soils, a thin stream of oil is introduced into a warm solution of glue, more concentrated than necessary, and mixed with it. Filler is poured into the remainder of the water necessary to bring the adhesive solution to the desired concentration. The resulting mass is gradually poured into the emulsion, stirring thoroughly. To obtain a more stable emulsion, as an emulsifier, you can add egg yolk (one yolk per 200 grams of solution), and then fill the filler. Egg yolk is a wonderful natural emulsion. If you dilute it with water (1: 2) and add chalk or dry white, you get a good soil.