IMPROVEMENTS IN THE PREPARATION OF COLORING MATTERS FOR DYEING AND PRINTING
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by William Boaler at the Office of
the Commissioners of Patents, with his Petition, on the 14th March
1863. A communication from abroad by Robert Hodgson Gratrix, of
New York, in the United States of America.
I, WILLIAM BOALER, of Manchester, in the County of Lancaster, Merchant,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE PREPARATION OF COLORING MATTERS FOR DYEING AND PRINTING," to be
as follows:-
This Invention consists in the use of gases, such as those arising from the
decomposition of metals or other substances by means of acids. The gases so
produced are employed for acting upon aniline and its homologues in order to
produce oxidation or partial oxidation for the purpose of producing from
aniline coloring matters which may be used for industrial purposes. For
example, when nitric acid and mercury are brought into contact nitrous gas
will be evolved, or when sulphuric acid, chloride of sodium, and oxide of
manganese are put together, and heat is applied, chlorine gas will be formed;
other gases may also be used for the purposes of the Invention.
It will be manifest that several methods of producing gases may be devised,
but it will not be necessary to describe them in detail, as I do not claim as
new the production of the gases, but merely their application to the purpose of

page_text: the present Invention. As an example of the mode of carrying out this
Invention, I may say that I take 8 ounces of mercury and place the same in
a retort which is put in connection with a Woulfe's bottle into which 6 ounces
of aniline has been introduced. The mouth of the adapter from the retort
is to be lengthened so that the aniline in the bottle shall cover the embouchure
of the adapter. I then add 10 ounces of good commercial nitric acid (made
by preference from nitrate of potash) to the mercury in the retort, and I well
close the stopper of the retort. I at first apply iced water to the retort to
prevent the action of the acid on the mercury from being too rapid and
energetic. The red gas is allowed to pass through the aniline, taking care
to gradually increase the temperature of the retort by the application of heat
as the decomposition of the acid takes place. The liquid in the retort will
then gradually become nearly colorless, and all action will cease, notwith-
standing the application of heat to assist the decomposition, as the materials
in the retort will have become exhausted. The aniline on the Woulfe's
bottle may now be removed, and an equal measure of nitric acid must be
added by degrees and with great care so as to prevent it from heating, which
may partly be prevented by placing the bottle in iced water. The mixture of
aniline and acid will have changed from a brown to a red color, and after
awhile will pass to a green bronze color; the mixture may now be placed in
a suitable vessel and heat be carefully applied until the desired result may
be obtained. The action should then be suspended and the liquid be poured
into a vessel containing a little cold water, it will then be found to have
assumed the appearance of dark pitch, and upon being boiled in water it will
give a deep blue purple color, which, when purified by any or some of the
methods used in purifying aniline colors, will communicate to silk, woollen,
and cotton, a purple blue color. According to the proportions of the gas
and acid that may be employed shades of color may be produced from a
color like magenta to blue and without being boiled, or in some cases when
boiled a yellow color will be produced. The shade or color may be modified
by treating the coloring matter with acids or alkalies according to the color
or shades desired to be produced.
I do not confine myself to the use of any particular gas, or to gas made in
the particular way above mentioned, nor to the use of nitric acid alone, as
other acids will produce the same results.
The peculiar feature of novelty in the Invention is, however, the application
of gases to aniline, either alone or in conjunction with acids or metallic salts,
for producing coloring matters from aniline or other similar substances. The

page_text: coloring matter produced in this manner may also be treated by adding
thereto an excess of aniline so as to produce further and other shades. This
mixture may be treated either with or without heat, and with acids or alkalis,
according to the shade required.