Natural resin is a general term for special secretions from the body of certain plants or animals, usually a complex mixture of multiple chemical components. Plants are stimulated by the external environment, such as injury, infection, etc., and will exude resin at the wound site, the purpose of which is to repair the wound and protect itself from further damage (the formation mechanism of animal glue is similar). These natural substances can be naturally changed over time to form a hard, brittle transparent or transparent resin with a fine gloss on the surface.
Natural resin has good molding, adhesion, only soluble in essential oils or grease oils, some components can be soluble in alcohol, belongs to mixed materials. According to the difference between the softening point and melting point of natural resin, it can be divided into soft resin and hard resin, and the soft resin commonly used in folk painting art includes high-quality shellac, rosin and mati resin (mastic resin), etc.; Hard resins commonly used in painting include kaba grease and amber, and in the early days hard resins were generally used as painting media and to protect the surface of hard base paintings. For example, rosin resin is processed from the resin secretion of pine trees and can be used as a background paint for the picture, providing a smooth and uniform surface that makes the picture flatter, increases the durability of the picture, and prevents the pigment from falling off; A small amount of rosin resin can also be incorporated into alcohol to form turpentine when blending colors, and adding to the pigment can increase the viscosity and ductility of the pigment, making the pigment easier to control, and helping people create the details and textures of the painting; Or after the painting is finished, melting the rosin resin and applying it to the picture can increase the shine and protective effect of the picture, protect the painting from the erosion of the external environment, and prolong its preservation time.
Synthetic resins commonly used in the field of painting art include acrylic resin, alkyd resin, epoxy resin, etc. Among them, acrylic resin is a very common painting material in folk painting art, which dries very quickly, usually between minutes and hours, which is convenient for artists to complete their works in a short time, and can be coated multiple times to make the color more vivid. At the same time, acrylic resin has high color saturation and strong light resistance, and can be directly extruded from the tube without blending, which can effectively resist ultraviolet rays and is not easy to fade.