IMPROVEMENTS IN THE PRODUCTION AND MANUFACTURE OF CERTAIN YELLOW AND ORANGE COLORS
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by James Alfred Wanklyn at the
Office of the Commissioners of Patents, with his Petition, on the
5th December 1863.-A communication from abroad by Eugen Lucius,
of Hoechst-on-the-Main, Germany.
I, JAMES ALFRED WANKLYN, of the London Institution, Finsbury, in the
County of Middlesex, Chemist, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE PRODUCTION AND MANUFACTURE OF CERTAIN
YELLOW AND ORANGE COLORS," a communication to me from abroad by Eugen
Lucius, of Hoechst-on-the-Main, Germany, to be as follows:-
This Invention consists in the production of certain yellow and orange
colors from the insoluble residue, and also from the mother liquors obtained in
and resulting from the manufacture of what are known as aniline red dyes,
such as magenta and others, by any of the methods employed in their
preparation.
In order to obtain the desired colors from the insoluble residue resulting
from the production of aniline red colors from aniline, it is proposed to treat
the same with a solution of caustic or of the carbonate of potash, soda, or
ammonia, but it is preferred to employ a solution of caustic soda. The
residue, after having been thus heated (by which treatment certain acids
and impurities are removed), is dissolved in any suitable acid or acids, nitric
acid being however preferred, the degree of strength of the acid employed
varying according to the color and to the intensity of the colors it is desired
to produce. To the solution thus obtained an alkali or an alkaline carbonate,

page_text: by preference a solution of cold caustic soda, is added, so as to precipitate the
colors, which, after having been washed with water, may be employed in con-
junction with suitable solvents for the purposes of dyeing.
In order to obtain the desired colors from the mother liquors resulting from
the production of aniline red colors, before mentioned, they are, firstly, to be
treated with an alkali or with an alkaline carbonate, by preference, with a
cold solution of caustic soda, and the precipitate thus resulting, after having
been collected and washed, is treated in the manner herein-before mentioned
for the treatment of the insoluble residue resulting from the production of
aniline red dyes so as to obtain yellow or orange colors therefrom. The pro-
duction of a yellow or of an orange color will depend upon the strength of
the acids employed. If, for example, nitric acid be employed, and the acid
be very dilute, a yellow color will be obtained; if a stronger solution of the
acid be employed, an orange color will result.
It is preferred to employ the alkaline solutions at the ordinary temperature,
and, as before mentioned, preference being given to a solution of caustic soda,
which solution is prepared in about the following proportions, namely, one
part by weight of caustic soda dissolved in fifty parts by weight of water, but
other proportions may be used.
The alkaline earths and their carbonates may also be employed for pre-
cipitating the yellow or the orange colors from the acid solution, but a solution
of caustic soda, as herein-before mentioned, is preferred.