Formic Acid For Dyeing

Popular Mechanics, marraskuu 1909

Formic acid, which has become a formidable competitor to acetic acid in the dyeing trade of Germany, is found in a natural state in ants, caterpillars, leaves of fir and pine trees, and in the common nettle. it also forms itself in a distallation of sugar, starch, and tartaric acid. it is extracted commercially by heating crystallized oxalic acid with glycering, from which it is withdrawn by means of distillation.

Although chemically pure formic acid is used in small quantities for medical purposes, and to some extent in the manufacture of fruit essences, its chief commercial application is in the dyeing and tanning trades, in which its corrosive effect is of great value. For dyeing purposes it is now substituted where formerly 30 per cent acetic acid was used. it gives to mercerized cotton the rustling effect of silk, and in silk trades it is used advantageously to produce the sheen.