IMPROVEMENTS IN THE TREATMENT OF SUBSTANCES CAPABLE OF BEING
Year: 1872

page_text: LETTERS PATENT to Astley Paston Price, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Consulting Chemist, for the Invention
of "IMPROVEMENTS IN THE TREATMENT OF SUBSTANCES CAPABLE OF BEING
Scaled the 17th December 1872, and dated the 19th October 1872.
PROVISIONAL SPECIFICATION left by the said Astley Paston Price at the
Office of the Commissioners of Patents, with his Petition, on the
19th October 1872.
I, ASTLEY PASTON PRICE, of 47, Lincoln's Inn Fields, in the County
of Middlesex, Consulting Chemist, do hereby declare the nature of my
said Invention for "IMPROVEMENTS IN THE TREATMENT OF SUBSTANCES CAPABLE
OF BEING EMPLOYED FOR THE PURPOSES OF DYEING AND PRINTING," to be as
follows:-
In the production of what is known as red aniline dyes from aniline
the method generally adopted is to heat together a mixture of aniline or
that substance which is known as commercial aniline and arsenic acid
until the desired colors are produced. The result thus obtained is known
technically as the "melt," and the subsequent treatment or purification
of the melt is generally conducted as follows:-The melt is digested in

page_text: boiling water, and in some cases the solution is filtered and allowed to
cool in order to separate what is known as arseniate of rosaniline and
other compounds. The supernatant solution or the original solution of
the melt is treated with lime in order to separate the arsenic and the
arsenious acids which exist in the solution, either in combination with
rosaniline or with other coloring matters or otherwise.
The liberated base or what is known as rosaniline base is then dissolved
out by means of hot water, and is separated by crystallization. By this
process the arsenic and the arsenious acids are converted into arseniate
and arsenite of lime and thus rendered insoluble, and hitherto these
products have been of no practical value.
Now this Invention relates to the treatment of the before-mentioned
product, or the result of heating aniline with arsenic acid, and known as
the "melt" in such a manner as that the arsenious and the arsenic acids
contained in the solution of the melt shall be obtained in an available
condition and not as hitherto as a compound of lime possessing but little
if any commercial value, and it consists in adding to the solution of the
melt such an amount of ammonia or of ammoniacal liquor as shall
liberate the rosaniline base existing in such solution in the form of
arseniate or arsenite of rosaniline. After allowing the base thus
liberated to separate from the solution the said solution contained in a
suitable distillatory apparatus is submitted to the action of heat either
by applying heat externally or internally, or by the injection of a jet of
steam or otherwise. The compound of arsenious acid and ammonia is
thus decomposed, and ammonia is liberated, which, after having been
collected may be again employed or otherwise utilized. The arsenious
acid remaining in the solution may be separated therefrom by evaporation
and crystallization or otherwise. In this manner the arsenious acid may
be recovered in a condition capable of being reconverted into arsenic acid
as is well understood.
Any arsenic acid which had not been previously separated by
crystallization as arseniate of rosaniline will be found to be contained in
the residual solution after having effected the decomposition of the
solution of arsenite of ammonia by the employment of heat, and such
arsenic acid or arseniate of ammonia may bo separated either by
evaporation or by evaporation and crystallization.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Astley Paston Price in the Great Seal Patent Office,
on the 18th April 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ASTLEY
PASTON PRICE, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Consulting Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of October, in the year
of our Lord One thousand eight hundred and seventy-two, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Astley Paston Price, Her
special license that I, the said Astley Paston Price, my executors,
administrators, and assigns, or such others as I, the said Astley Paston
Price, my executors, administrators, or assigns, should at any time
agree with, and no others, from 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 In-
vention for "IMPROVEMENTS IN THE TREATMENT OF SUBSTANCES CAPABLE OF BEING
EMPLOYED FOR THE PURPOSES OF DYEING AND PRINTING," upon the condition
(amongst others) that I, the said Astley Paston Price, my executors or
administrators, by an instrument in writing under my hand and seal,
should particularly describe and ascertain the nature of the said In-
vention, 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 Astley Paston Price, do hereby declare
the nature of my 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:-
In the production of what is known as red aniline dyes, from aniline,
the method generally adopted is to heat together a mixture of aniline or
that substance which is known as commercial aniline and arsenic acid
until the desired colours are produced. The result thus obtained is known
technically as the "melt," and the subsequent treatment or purification

page_text: of the melt is generally conducted as follows:-The melt is digested in
boiling water, and in some cases the solution is filtered and allowed to
cool in order to separate what is known as arseniate of rosaniline and other
compounds. The supernatant solution or the original solution of the
melt is treated with lime in order to separate the arsenic and the
arsenious acids which exist in the solution cither in combination with
rosaniline or with other coloring matters or otherwise.
The liberated base, or what is known as rosaniline base, is then dis-
solved out by means of hot water, and is separated by crystallization.
By this process the arsenic and the arsenious acids are converted into
arseniate and arsenite of lime and thus rendered insoluble, and hitherto
these products have been of no practical value.
Now this Invention relates to the treatment of the before-mentioned
product or the result of heating aniline with arsenic acid, and known
as the "melt," in such a manner as that the arsenious and the arsenic
acids contained in the solution of the melt shall be obtained in an
available condition, and not as hitherto as a compound of lime possessing
but little if any commercial value, and it consists in adding to the
solution of the melt such an amount of ammonia or of ammonia liquor
as shall liberate the rosaniline base existing in such solution in the form
of arseniate or arsenite of rosaniline. After allowing the base thus
liberated to separate from the solution the said solution contained in
a suitable distillatory apparatus is submitted to the action of heat
either by applying heat externally or internally, or by the injection of a
jet of steam or otherwise. The compound of arsenious acid and ammonia
is thus decomposed, and ammonia is liberated, which, after having been
collected may be again employed or otherwise utilized. The arsenious
acid remaining in the solution may be separated therefrom by evaporation
and crystallization or otherwise. In this manner the arsenious acid may
be recovered in a condition capable of being reconverted into arsenic acid
as is well understood.
Any arsenic acid which may not have been proviously separated by
crystallization as arseniate of rosauiline will be found to be contained in
the residual solution, and having effected the decomposition of the
solution of arseniate of ammonia by the application of licat, or by pre-
ference by the employment of steam, the arsenic acid may be separated
either by evaporation or by evaporation and crystallization.

page_text: Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider
to be novel and original and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is, the treat-
ment of the arsenical compounds of rosaniline herein mentioned in the
manner and for the purposes herein-before described.
In witness whereof, I, the said Astley Paston Price, have to this
my Specification set my hand and scal, this Tenth day of April,
One thousand eight hundred and seventy-three.
ASTLEY PASTON PRICE. (L.S.)