The bark from several species of oak contains up to 14% water-soluble dyes and tannins. The wood also contains tannins but in smaller quantities. Oak tannins contain pyrogallol and condensed tannins. They have a neutral pH, a moderate salt content and are used to produce a fine, heavy leather. Oak bark extracts are also used for dyeing. They produce colors ranging from black (black oak, Quercitron) to rose-tan (red oak) to khaki (white oak). Oak dyes have good fastness to light and washing.
Synonyms and Related Terms
casca de carvalho (Port.); oak extract
Resources and Citations
- G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 556
- Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
- Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
- F. Crace-Calvert, Dyeing and Calico Printing, Palmer & Howe, London, 1876