Why is oil painting more expensive than other paintings? It’s not that the technique is more difficult than watercolor gouache, nor that the painting materials are more expensive. The simple and popular reason is that it can be preserved for a long time.
In order to keep the oil painting for a long time, we need to abide by an eternal basic rule of “fat cover thin“. What is “fat cover thin” how to achieve fat cover thin is the content of this article today.
Fat refers to “oil”, fat cover thin refers to painting oil always let the last layer of oil multi-color thick pressure oil less thin. This is because, according to the characteristics of the dry oil used in oil painting summed up the law. Fat and thin oil painting can best protect the surface of the oil painting, bright color, firm and durable.
Oil paint changes from liquid to solid through the oxidation process of oil, so the drying of oil paint needs to inhale oxygen, so the drying always starts from the surface that first touches the air. A pair of oil painting feels that the surface is dry after one week, but in fact, even if it is not completely dry after one year, this is the natural law of chemical reaction, 73% in one week, 84% in ten years, 98% in one hundred years 。 When painting oil paintings, if the lower layer and the upper layer have the same oil content, the upper layer will dry first, because the upper layer seals the oxidation of the lower oil paint, where it oxidizes itself. The fat pigment is more flexible and more suitable for the changes of environment temperature and humidity, while the thin pigment is brittle after drying. If the thin pigment is used to cover the fat, it will be just pressed and soft, and the thin one will crack. If the “thin” on the top is dried first, and the “fat” on the bottom is still drying slowly in time, it will be easy to crack the upper layer with time, and then it will start to peel off a little longer. The more oil there is, the brighter and smoother the surface, and it is difficult for thin pigments with less oil content to adsorb on it.