|
|
Rosin, also called colophony or Greek pitch (Latin: pix græca), is a solid form of resin obtained from pines and some other plants, mostly conifers, produced by heating fresh liquid resin to vaporize the volatile liquid terpene components. It is semi-transparent and varies in color from yellow to black. At room temperature rosin is brittle, but it melts at stove-top temperature. It chiefly consists of various resin acids, especially abietic acid. The term "colophony" comes from colophonia resina, Latin for "resin from Colophon," an ancient Ionic city. Fine art uses rosin for tempera emulsions and as painting-medium component for oil paintings. It is soluble in oil of turpentine and turpentine substitute, and needs to be warmed. In a printmaking technique, aquatint rosin is used on the etching plate in order to create surfaces in gray tones. |