IMPROVEMENTS IN TREATING ANILINE COLOURS FOR DYEING AND PRINTING
Year: 1864

page_text: LETTERS PATENT to Edward Thomas Hughes, of the Firm of Hughes
and Son, Patent Agents, 123, Chancery Lane, London, for the Invention
of "IMPROVEMENTS IN TREATING ANILINE COLOURS FOR DYEING AND PRINTING."
-A communication from abroad by August Samuel Leopold Leonhardt,
of Berlin, Prussia.
Sealed the 2nd June 1865, and dated the 6th December 1864.
PROVISIONAL SPECIFICATION left by the said Edward Thomas Hughes
at the Office of the Commissioners of Patents, with his Petition, on the
6th December 1864.
I, EDWARD THOMAS HUGHES, of the Firm of Hughes and Son, Patent
Agents, 123, Chancery Lane, London, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN TREATING ANILINE COLOURS FOR DYEING AND
PRINTING," a communication to me from abroad by August Samuel Leopold
Leonhardt, of Berlin, Prussia, to be as follows:-
I take the violet and blue aniline colours, such as are prepared by means
of magenta (it is of no consequence by what method the same is made, whether
with arsenic acid or salts of mercury or other suitable salts) in a dry or wet
state, and dissolve them in alcohol or aniline, as it is generally sold, or in
other suitable solvents. From this solution I precipitate the colour in a very
finely divided state. This is effected from the alcohol solution by letting the
same drop into a sufficiently large quantity of cold water, which is well
stirred, or into a cold and sufficiently large quantity of an aqueous salt solution

page_text: prepared with muriate of soda or sulphate of of soda, or chloride of calcium,
stirring it well also, or into a sufficiently large quantity of cold water alkalized
with carbonate of potash, soda, ammonia, caustic ammonia, or other suitable
substance, likewise stirring it well. When I use a solution of aniline I drop
this same solution into a large quantity of cold water, to which I have added
sulphuric acid, muriatic acid, nitric or any other suitable acid, in quantity
equivalent to the aniline employed as a solvent, or in quantity slightly
exceeding the equivalent, stirring well the liquid. I thus obtain an exceedingly
finely divided precipitate of colours. In both cases the precipitate is separated
by means of filtering or by means of a centrifugal apparatus, washed, and is
then ready for use.
The alcoholic filtrate may be treated in the usual way for extracting the
alcohol, the filtrate containing aniline salt for extracting the aniline.
For carrying this Invention efficiently into practical effect, the following
proportions are preferred:-1 pound of dry colour as obtained in commerce is
dissolved in 20 to 40 pounds of the most concentrated alcohol made boiling
hot, and this coloured solution is to be slowly dropped into 200 to 400 pounds
of cold water or into cold saline solutions composed of the same quantity of
water mixed with common salt or sulphate of soda, or chloride of calcium.
Or the coloured alcoholic solution may be dropped into cold alkaline solutions,
such as 200 to 400 pounds of water containing 3 pounds of potash or soda, or
ammonia, or lime in their caustic state or as carbonates.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Thomas Hughes in the Great Seal Patent Office on
the 6th June 1865.
TO ALL
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
THOMAS HUGHES, of the Firm of Hughes and Son, Patent Agents, 123,
Chancery Lane, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of December, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
ine, the said Edward Thomas Hughes, Her special license that I, the said
Edward Thomas Hughes, my executors, administrators, and assigns, or
such others as I, the said Edward Thomas Hughes, my executors, admi-
nistrators, and assigns, should at any time agree with, and no others, from

page_text: time to time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "IMPROVEMENTS IN TREATING ANILINE COLORS FOR DYEING
AND PRINTING," a communication to me from abroad by August Samuel
Leopold Leonhardt, of Berlin, Prussia, upon the condition (amongst
others) that I, the said Edward Thomas Hughes, my executors or admi-
nistrators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature of
the said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Edward Thomas Hughes, do hereby
declare the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement (that is to say):-
I take the blue and violet colors of commerce (obtained from magenta, and
which are insoluble in water) in the wet or dry state, and dissolve them
completely in a sufficient quantity of strong alcohol, and I precipitate the
color from this solution in an extremely fine state of subdivision as follows:-
I allow it to fall into a sufficiently large quantity of cold water or a cold
solution of any neutral salt, such as common salt, chloride of calcium, sulphate
of soda, or other suitable neutral salt; or I allow it to fall into a sufficiently
large quantity of cold water containing caustic alkali, such as caustic potash,
soda, or ammonia, or their carbonates, so as to remove as much as possible tho
acid either free or combined contained in the colors, and I keep the fluid used
for the precipitation in a constant brisk agitation. By any of the aforesaid
means I obtain these colors in an extremely fine state of subdivision, whereby
they are rendered more easily soluble in slightly acidulated hot water. After
precipitation I collect the insoluble matter on a filter, and wash it well. The
filtrate consisting of the alcohol mixed with a large quantity of water is then
distilled to recover the said alcohol and the precipitate without further
preparation, is ready for use in dyeing and printing.
In carrying this Invention into practical effect I find the following pro-
portions and quantities to answer very well, though I do not confine myself
strictly to the quantities set forth, as they are capable of modification :-I
take one part by weight of any of the aforesaid named dry aniline colors of
commerce, and dissolve them in from twenty to forty parts of the strongest

page_text: boiling alcohol. The light shades of violet require the least alcohol, and the
blue and dark shades of violet require the most. The quantity of alcohol used
varies also in proportion as the solution is effected under pressure or not.
The vessels used for dissolving may be of any suitable form, but to prevent
loss of alcohol I prefer closed metallic vessels, and for the same reason I
prefer closed metallic vessels for the subsequent precipitation, and supply each
of them with suitable agitators. In the vessel used for precipitation I put
about two hundred to four hundred parts of cold water, or about two hundred
to four hundred parts of a cold solution of common salt containing about one
part of salt to five parts of water, or about two hundred to four hundred parts
of cold water containing three parts of caustic potash, soda, or ammonia, or
their carbonates, or the same quantity of a mixture of any proportion of the
before-mentioned saline or alkaline solutions.
During brisk and constant agitation of the precipitating liquid I allow the
alcoholic solution of the coloring matter to fall into it either in single drops or
a very fine stream, and by these means I precipitate the previously dissolved
coloring matter in this fine state of subdivision. The insoluble color is now
separated from the filtrate by any of the well-known kinds of filters, or by a
centrifugal drainer. The precipitate after washing is then ready for use.
The filtrate is then submitted to any of the known means of distillation,
for the purpose of recovering the contained alcohol in a concentrated
form, which recovered alcohol is then used for dissolving further quantities
of the colors. I can also effect this fine subdivision of the said colors
by dissolving them perfectly in commercial analine. The clear solution
thus obtained. is then allowed to drop under the same conditions as those
described for the first process, into twenty times its quantity of cold water
containing hydrochloric acid of 22° Baumé, equal to one and a quarter times
the weight of the analine used. The so obtained precipitate is then separated
from the filtrate by the means specified in the first process, and after being
well washed is fit for use. The filtrate is then subjected to any of the known
processes for the purpose of recovering the aniline. I can also effect this fine
subdivision of the said colors by dissolving them in concentrated sulphuric
acid in the following manner :-I take one part by weight of the afore-
mentioned color, and dissolve it in twenty to thirty parts of concentrated
sulphuric acid of about 66° Baumé, either cold or at a temperature not
exceeding fifty centigrade, so as to avoid the formation of that blue known as
Nicholson's soluble blue, which I consider a disadvantage. The clear solution
thus obtained is then allowed to drop into ten times its weight of cold water,
or water containing sufficient alkali to neutralise the sulphuric acid used

page_text: under the same precautions as those specified above. The finely divided
precipitate is separated from the clear liquid either by filters or a centrifugal
drainer, and after washing is ready for use.
Although the two last-mentioned processes will answer very well, in practice
I find the first one preferable.
Having thus fully described the nature and particulars of the said Invention,
and the manner of carrying the same into practical effect, I desire it to be
understood that I claim as new, the rendering of the blue and violet colors of
commerce obtained from magenta, and which are insoluble in water, in a fine
state of subdivision, so that without further use of alcohol or other solvent
they are in a fit condition for use in dyeing and printing, by first dissolving
them in alcohol or aniline, and subsequently allowing the solutions so
obtained under brisk and constant agitation to drop into cold water alone, or
into cold water containing in solution neutral salts, caustic or carbonated
alkali, or (as in the last-described process, when aniline is used) into cold
water containing hydrochloric acid, and subsequently recovering the solvent
employed as described in the last process.
In witness whereof, I, the said Edward Thomas Hughes, have hereunto
set my hand and seal this Sixth day of June, in the year of our Lord
One thousand eight hundred and sixty-five.
E. T. HUGHES. (L.S.)