Gum copal

Taking two pounds of balsam-copiba, five pounds of the essence of the myrde-tree, one pound of gum-copal, two pounds of rosin, and three pounds of rendered suet. 

XOLOCH COPALLI - The Gum Copal XYLAGIUM — Holy Wood. 

Diamyl oxalate is a colorless, oily liquid miscible with mast lacquer solvents, oils and hydrocarbons. It is a solvent far ester gum, copal ester, "Cumor" resins, alkyd resins, mastic, nitrocellulase and shellac. It is used as a plasticizer and in paint and varnish removers. Like other oxalates, it has a tendency to hydrolyze. 

CAS 9000-14-0 EINECS/ELINCS 232-527-9 Synonyms Copal (INCI) Cowrie Gum copal Kaurie Resin copal... 

Gum cassia. See Cassia gum Gum copal. See Copal resin Gum cyanopsis. See Guar (Cyanopsis tetragonoloba) gum... 

Morkhade DM, Fulzele SV, Satturwar PM, Joshi SB. Gum copal and gum damar Novel matrix forming materials for sustained drug delivery. Indian J Pharm Sci. 68 (1) 53-58, 2006. 

In addition to shellac a number of other natural resins find use in modem industry. They include rosins, copals, kauri gum and pontianak. Such materials are either gums or very brittle solids and, although suitable as ingredients in surface coating formulations and a miscellany of other uses, are of no value in the massive form, i.e. as plastics in the most common sense of the word. 

Lack-farbstoff, m. dye for lake making, -firms, m. lac varnish, lacquer lake varnish varnish. -fimislack, m. lac lake, -fiache, /. varnish surface lacquer coat, -harz, n. varnish gum, varnishing resin, esp. copal gum lac. -haut,/. lacquer (or varnish) film. 

French polish is employed upon flat surfaces, and consists simply ofa solution of resin in spirit of wine. The simplest sort of French polish may be made by dissolving one and a half parts of shell-lao in eight ports of spirit of wine. Such a polish is very durable, but many other gum-resins are employed. A good dark-colored polish is prepared from one pound of shell-lac, half a pound pf gnm-benzoin, and one gallon of spirit of wine. Others reaommend twelve, ounces of shell-lac, three ounces of copal, six ounces of gum-arabic, to one gallon of spirit. 

Dissolve 16 parts gum-arabic in the least possible quantity of water, and mix with it 9 parts phosphorus iu powder (see No. 4338) then add 14 parts nitre (saltpetre), and 16 parts of either vermilion (red sulphuret of mercury), or binoxide (black oxide) of manganese, aud form the whole into a paste. Dip the matches into this pasto, and then let them dry. When quite dry they are to be dipped into a very dilute copal or lac varnish, and again dried by this means they are less likely to suffer from damp weather. 

Kauri gum is of a darker colour than most copals (Fig. 1.34), and, like the Japanese copal, some of it is turning into amber. It is mosdy transparent and it contains few inclusions. Insect inclusions are extremely rare. It has been successfully worked into a variety of decorative objects and jewellery. 

Our knowledge of the history of copal is also confined to one species New Zealand kauri gum. 

The carbonates, sulphates, and borates are decomposed. The sulphides of the alkalies and alkaline earths are decomposed while the sulphides of arsenic, antimony, molybdenum, zinc, cadmium, tin, iron, lead, copper, mercury, and palladium are not attacked. Cobalt sulphate is not attacked, while the sulphates of the alkalies and alkaline earths are attacked and dissolved. Alkali tungstates, ammonium arsenite and arsenate, copper arsenite, ammonium magnesium arsenate, ammonium molybdate and vanadate, potassium cyanide and ferrocyanide are decomposed. Paraffin is not attacked shellac, gum arabic, gum tragacanth, copal, etc., are decomposed. Celluloid is slowly attacked. Silk paper, gun cotton, gelatin, parchment are dissolved. M. Meslans 22 has studied the esterification of alcohol by hydrofluoric acid. 

Other special macromolecules are known, and some were analyzed by pyrolytic techniques. Among these are special gums and lacquers such as mastic, gum elemi, copal, kauri, sandarac, shellac, colophony, amber, etc. [4]. These materials have narrow fields of applications and were not included in this book. 

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