| 释义 |
catechu|ˈkætɪʃuː, -tʃuː|
[In. mod.L. catechu (also Ger. katechu, kateschu), app. ad. Malay kachu, (Tamil, Telugu, Canarese kācchu, kaycchu, kāshu) catechu (of acacia). The direct representatives of the latter are Pg. cacho, F. cachou; the exact history of the form catechu is obscure. See also the other names cachou, cashou, cate2, cutch.]
a. A name given to several astringent substances, containing from 40 to 55 per cent. of tannin, which are obtained from the bark, wood, or fruits of various Eastern trees and shrubs. They are used in medicine, and in tanning, calico printing, and dyeing. Also attrib. or Comb.: catechu brown, a brown colour produced by the use of catechu as a dye.
The name was apparently first applied (in Europe) to the pale sort called also gambier, obtained from the leaves and young shoots of Uncaria or Nauclea Gambir; this is the Catechu of Pharmacy (Syd. Soc. Lex.): when first brought to Europe in the 17th c. it was from its appearance believed to be an earth, and called Terra Japonica. The dark sort obtained from the wood of Acacia Catechu, is more commonly called cutch; of this Pegu Catechu is a good variety. (There is doubt whether the connexion with Japan assumed in the name terra japonici is not purely imaginary, and owing to the Burmese name for Acacia Catechu, sha-pin, shabin, or shaben.)
[1654Schröder Pharmacop. Medico-chym. (Lyons), Catechu..Terra Japonica..genus terræ exoticæ (Y.) 1679Hagendornius (title), Tractatus Physico-Medicus de Catechu, seu Terra Japonica.] 1683Weekly Mem. Ingen. 157 A history of Catechu, or Terra Japonica. 1741Compl. Fam.-Piece i. i 64, 2 Drams of choice Catechu or Japan Earth. 1805C. Hatchett in Phil. Trans. XCV. 288 Twenty grains of the common cutch or catechu being dissolved in nitric acid. 1860Ure Dict. Arts (ed. 5) I. 805 Catechu Brown, rich and transparent. 1875Ibid. (ed. 7) I. 749 Gambir Catechu..imported under the name of Gambir, from Singapore and some of the neighbouring islands..In the trade it is distinguished from the black catechu and cutch by the name of Terra Japonica. 1880J. Dunbar Pract. Papermaker 41 Catechu dyed papers. 1902Encycl. Brit. XXVII. 564/1 Catechu browns are fast to a variety of influences.
b. catechu acacia, -tree; the Acacia Catechu.
1831J. Davies Manual Mat. Med. 450 Catechu tree. 1876Harley Mat. Med. 640 Catechu Acacia is a small tree, with straggling thorny branches, and hard, heavy, dark-red wood.
Hence ˌcatechuˈtannic acid, the tannic acid of catechu.
1863–75Watts Dict. Chem., Catechutannic acid softens when heated, and yields by distillation a yellow empyreumatic oil. |