21.3.19

A New Brown Dye from Coal-Tar

Manufacturer and Builder 7, 1875

A New Brown Dye from Coal-Tar has been patented in England; it is made by treating four parts of the residue obtained by the purification of carbolic acid with a mixture of one part oxalic and one part sulphuric acid, and keeping it for about a week at a temperature of about 300° Fah, The mixture is then repeatedly washed with water, and again heated to drive out all moisture; it is then dissolved in alcohol, and may be used for dyeing brown.

Ei kommentteja :