copal
a hard aromatic resin, yellow, orange, or red in colour, obtained from various tropical trees and used in making varnishes and lacquers
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
copal
[′kō·pəl] (materials)
Hard, resinous substance exuded from certain trees in the East Indies, South America, and Africa and used in varnish and printing ink.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
copal
Resin of natural origin used in varnishes to provide gloss and hardness.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
Copal
a class of natural fossil resins composed primarily of resin acids. Copals are extremely hard, with a high melting point (up to 360°C and higher) and great chemical stability. Their density is 1.03–1.07 g/cm3. The color of copals ranges from colorless to brown. The names of copals are often derived from the places of extraction, for example, Zanzibar, Mozambique, Angola, Borneo, and Brazil copals. Copals are widely used in the manufacture of varnishes. With the appearance of synthetic resins, their importance has decreased.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.