Cotton mineral acids

Basic colouring matters are those the solutions of which are decolorised by mineral acids and give a coloured precipitate with tannin (best in presence of sodium acetate). When acidified with sulphuric acid and shaken with ether, their solutions give up nothing to the solvent. They dye animal fibres in a neutral bath or one faintly acid with acetic acid, without a mordant, and they dye cotton in a tannin bath. Mineral acids remove them completely from the fibres on which they are fixed. 

K. Selby The attack of mineral acid on cotton does not always follow the same course—i.e.9 a rapid solubilization of the first 10%). Jeffries, Roberts, and Robinson (1) have recently shown that the size of the rapidly hydrolyzed fraction varies with acid concentration and deduce that two clearly defined fractions are not present in the structure but that reaction is at an accessible surface, the accessibility depending on the concentration of the hydrolyzing acid. ... 

The use of crystalline nanoparticles of cellulose (CNP) allows for paving a new path for the development of nanocosmetics. The CNP for cosmetics application can be produced by hydrolysis of pure cotton cellulose with mineral acids as was described in Section 9.3.1. The paste of CNP for cosmetic application was obtained by evaporation of dilute aqueous dispersion. The powder of CNP was prepared by freeze-drying of the aqueous dispersion. Testing has shown that the obtained powder of CNP meets requirements of the US pharmacopeia 23/NF 18 for inactive medical excipients (Table 9.13). 

Cellulose Cotton Viscose 100 G P VG Copper sulphate, mineral acids, acid salts, bacteria... 

The process was discovered and patented in 1856 by William Henry Perkin, at a time when the wool and cotton industries were enjoying a trade boom and the demand for colorants threatened to outstrip the supplies of natural dyes, mostly vegetable, then available. Crude benzol from the well-established coal-gas and coal-tar distillation industries was commercially available, as were mineral acids, alkalis, bichromates, saltpetre and other materials. Mauveine followed by other synthetic dyes from Perkin Sons, soon became a success. Other, rival pioneers built factories in the UK and Europe and introduced new dyes, the result of their own research work. 

Various formulations are provided under this heading by Terry (1893), the common factor being the likely creation of complex oiganic residues. The three recipes provided are as follows (1) Fused caustic potash is digested in alcohol, and the liquor filtered and heated till a brown powder is thrown down, which is filtered and washed with acidulated water (2) Waste cotton, peat, or brown coal, heated with an alkali (3) Farinaceous matters carbonised by mineral acids. ... 

Acid colouring matters give solutions which are not decolorised by mineral adds and are not precipitated by tannin. When their solutions, addified with sulphuric acid, are shaken with ether, the latter dissolves the colouring matter and leaves a residue when evaporated. They do not dye wool and silk in a neutral bath but do so in an acid bath (with sulphuric add) they are little suitable for cotton. 

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