Muco-Cellulose.—This term is applied to certain compound celluloses present chiefly in mucilages, gums, and in seaweeds (Algæ). The natural substances are all of commercial importance—Iceland moss, Carragheen, Algin, etc.
Naphtha.—One of the products of the dry distillation of wood, usually described as wood-naphtha, or wood spirit.
Nitro-Cellulose.—The treatment of cellulose with nitric acid gives a number of nitro-celluloses according to the conditions of the process. (See Cellulose Nitrates.)
Oxalic Acid.—A substance of great commercial importance prepared by heating the sawdust of soft wood, such as pine, fir, and poplar, with strong solutions of mixed caustic soda and potash to dryness. The wood yields after six hours a greyish mass containing about 20 per cent. of the acid, which is separated out by water and then crystallised.
It is used for bleaching, and as a discharge in calico printing and dyeing.
Oxy-Cellulose.—A white friable powder produced by treating cellulose with nitric acid at 100° C. The oxidation of cellulose is brought about by several reagents such as chromic acid, hypochlorites of lime and soda, chlorine, and permanganates. The extent to which cloth has been damaged by overbleaching may be determined by a simple test with methylene blue solution, which is readily absorbed by oxy-cellulose present in such fabrics.
Parchment.—A tough paper prepared by the action of sulphuric acid on unsized paper. (See page [137].)
Pectins.—(See Pecto-Cellulose.)
Pecto-Cellulose.—A generic term applied to many important fibrous materials, such as flax, straw, esparto, bamboo, phormium, ramie, &c., which on alkaline treatment yield cellulose for paper-making, and a non-fibrous soluble residue of complex composition. These soluble derivatives are known as pectin (C32H48O32), pectic acid (C32H44O30), and metapectic acid (C32H28O36). Although the soluble constituents of the pecto-celluloses amount to 50 per cent. by weight in most cases, no process for the recovery of the product in a commercial form has yet been devised. (See description of Soda recovery, page [78].)