IMPROVEMENTS IN THE MANUFACTURE OF VIOLET DYE-STUFFS
Year: 1865

page_text: LETTERS PATENT to James Alfred Wanklyn, of the City of London,
Professor of Chemistry, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF VIOLET DYE-STUFFS."
Sealed the 23rd February 1866, and dated the 26th August 1865.
PROVISIONAL SPECIFICATION left by the said James Alfred Wanklyn at
the Office of the Commissioners of Patents, with his Petition, on the
26th August 1865.
I, JAMES ALFRED WANKLYN, of the City of London, Professor of Chemistry,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF VIOLET DYE-STUVES," to be as follows:-
It has been shewn by Doctor Erlenmeyer, of Heidelberg, that hydriodic
acid converts glycerine into a chemical compound containing iodine and
isomeric with the common iodide of propyl produced from common propylic
alcohol by the usual process, but very different from the common iodide of
propyl in its behaviour with chemical re-agents. This compound, obtained
as aforesaid by making bydriodic acid act upon glycerine, has received the
names "iodide of isopropyl and "hydriodate of propylene." I have
discovered that this iodide of isopropyl or hydriodate of propylene is

page_text: capable of yielding beautiful violet dye-stuffs by being made to act upon
rosaniline.
My process for manufacturing violet dye-stuffs is as follows:-I take about
equal weights of iodide of isopropyl and rosaniline and alcohol, and heat the
mixture to about 212° Fahrenheit in a suitable vessel for about eight hours.
I then take the product resulting from this operation and boil it with caustic
soda, and thereby obtain an organic base, the salts of which are violet
dye-stuffs, and capable of being used for dyeing and printing in the usual
manner.
By employing an additional quantity of the iodide of isopropyl in the above-
mentioned process a bluer violet is obtained.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Alfred Wanklyn in the Great Seal Patent Office
on the 24th February 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
ALFRED WANKLYN, of the City of London, Professor of Chemistry, send
greeting.
"WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of August, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said James Alfred Wanklyn, Her special license that I, the said James Alfred
Wanklyn, my executors, administrators, and assigns, or such others as I, the said
James Alfred Wanklyn; my executors, administrators, and assigns, should 'at
any time agree with, aud no others, from time to time and at all times there-
after 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 THE
MANUFACTURE OF VIOLET DYE-STUFFS," upon the condition (amongst others) that
I, the said James Alfred Wanklyn, my executors or administrators, 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 James Alfred Wanklyn, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement (that is to say) :-
It has been shewn by Dr. Emil Erlenmeyer, of Heidelberg, that glycerine is
converted by means of hydriodic acid into a compound containing iodine, and
which is known as iodide of isopropyl or. bydriodate of propylene. Now I
have discovered that this iodide of isopropyl or hydriodate of propylene is
capable of yielding beautiful violet dye-stuffs when brought into contact with
and made to act upon rosaniline, which is, as is well known, the base of the
dye-stuffs derived from commercial aniline, and known commercially as
magenta.
In order to carry out my Invention I proceed as follows:-I take about
equal parts by weight of iodide of isopropyl or hydriodate of propylene and
rosanline and alcohol, and heat the mixture contained in a closed vessel
provided with a safety valve and pressure guage to a temperature of about
212° Fahrenheit, and continue the application of heat until the desired violet
tint is obtained, which may be known by removing from time to time a small
quantity of the product, and dissolving the same in alcohol or other solvent,
and observing the color of the solution so produced.. The desired color
having been thus obtained the mass is dissolved in alcohol or other solvent,
and the solution after the separation of any insoluble matter may be at once
employed for the purposes of dyeing and printing, or the solution may be
heated to about 180° Fahrenheit, and then be mixed with an aqueous solution
of caustic soda, containing in solution an amount of caustic soda equal in
weight to the rosanline originally employed, and then diluted with water
so long as any considerable amount of precipitate is deposited. The precipitate
having been collected and washed is combined with an acid, such, for example,
as acetic acid, which is effected by heating the same with the dilute acid
until the desired combination has taken place. The product thus resulting is
separated from the solution by decantation or filtration, and may be dried or
be at once dissolved in alcohol or other suitable solvent, and be employed for
the purposes of dyeing and printing in a manner which is well understood by
aniline color dyers.
Although I have mentioned that about equal parts by weight of iodide of
isopropyl, rosanline, and alcohol may be employed for the production of
violet dyes, I wish it to be understood that I do not confine myself to those
proportions, as I have found that the color will vary according to the propor-
tions in which the iodide of isopropyl and rosaniline are employed with the
alcohol; the larger the proportion of iodide of isopropyl employed the bluer
will be the violet color produced.

page_text: Although I have mentioned the employment of alcohol in conjunction with
the iodide of isopropyl and rosaniline, I wish it to be understood that I do not
limit myself to its employment only, as other substances such as wood naptha
or pyroxylic spirit may be employed.
In witness whereof, I, the said James Alfred Wanklyn, have hereunto.
set my hand and seal, this Twenty-third day of February, in the year.
of our Lord One thousand eight hundred and sixty-six.
JAMES ALFRED WANKLYN. (L.S.)