Liquid color manufacturing process

A surfactant was defined in Chapter 8 as an agent, soluble or dispersible in a liquid, which reduces the surface tension of the liquid [1]. It is helpful to visualise surfactant molecules as being composed of opposing solubility tendencies. Thus, those effective in aqueous media typically contain an oil-soluble hydrocarbon-based chain (the hydrophobe) and a smaller water-solubilising moiety which may or may not confer ionic character (the hydrophile). The limitations of space do not permit a comprehensive detailed treatment of the chemistry of surfactants. The emphasis is therefore on a broad-brush discussion of the principal types of surfactant encountered in textile preparation and coloration processes. Comprehensive accounts of the chemistry and properties of surfactants are available [2-13]. A useful and lucid account of the chemistry and technology of surfactant manufacturing processes is given by Davidsohn and Milwidsky [ 14] ... 

The acid solution, which now contains only sulphate of copper, is evaporated in lead boilers till it is fit to crystallize. It is then put into the crystallising pans, aud the mother waters are further evaporated, to obtain more crystals. This process is continued till the liquid becomes very concentrated, and consists almost entirely of sulphuric acid. In tills state it is termed black add, on account of its color, which is due, in groat part, to organic matters, dust, and other impurities, which fall in it during the evaporation in tho crystallising pans. The black acids, purified by concentration, may either be employed to repeat tho same operation, or turned to useful account in different manufacturing processes, wliich do not require that the sulphuric acid should be pure and highly concentrated,... 

The commercial oil of xriiriol, largely used iu manufacturing processes, is a more or less deeply colored, oily liquid, varying in sp. gr. from 1.S33 to 1 B4 2, and iu concentration from 93 per cent to 9H per cent of true... 

The commercial oil of vitriol, largely used in manufacturing processes, is a more or less deeply colored, oily liquid, vary-... 

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