IMPROVEMENTS IN THE "
Year: 1863

page_text: LETTERS PATENT to William Henry Perkin, of Seymour Villa, Sudbury,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN THE
"
PROVISIONAL SPECIFICATION left by the said William Henry Perkin
at the Office of the Commissioners of Patents, with his Petition, on
the 6th November 1868.
I, WILLIAM HENRY PERKIN, of Seymour Villa, Sudbury, in the County of
Middlesex, do hereby declare the nature of the Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF COLORING MATTERS SUITABLE FOR DYEING AND PRINTING,"
to be as follows:-
This Invention consists in producing from mauveine (or the base of the
coloring matter generally known as mauve or aniline purple), or it may be
from a carbonate or feeble combination of the said base, other coloring
matters of redder and also of bluer shades. To produce the redder colors, the
mauveine is subjected to the action of the chloride, bromide, iodide, or other
salt of methyl, ethyl, propyl, buthyl, amyl, ethylene, amylene, allyl, or other
organic radical. I generally employ the iodides or bromides of methyl, ethyl,

page_text: or amyl. A quantity of mauveine is mixed with about 5 or 6 times its weight
of alcohol, and then one of the above compounds added, it is then allowed to
stand for some days, or the action may be accelerated by heat or light. It is
then filtered off from any unchanged mauveine. By this method coloring
matters of a red purple shade are obtained. To produce violet or bluer colors
the red purple product is treated with alkalies or alkaline solutions and the
resulting product purified.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Henry Perkin in the Great Seal Patent Office on
the 6th May 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HENRY PERKIN, of Seymour Villa, Sudbury, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of November, in the year of our
Lord One thousand eight hundred and sixty-three, in the twenty-seventh
year of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said William Henry Perkin, Her special licence that I, the
said William Henry Perkin, my executors, administrators, and assigns, or
such others as I, the said William Henry Perkin, my executors, adminis-
trators, and 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 Inven-
tion for "IMPROVEMENTS IN THE MANUFACTURE OF COLORING MATTERS SUITABLE
FOR DYEING AND PRINTING," upon the condition (amongst others) that I, the
said William Henry Perkin, my executors or administrators, by an instrument
in writing under my, or their, or one of their hands and seals, should par-
ticularly 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 William Henry Perkin, do hereby
declare the nature of the said Invention, and in what manner the same is

page_text: to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention consists in producing from mauveine (or the base of the
coloring matter generally known as mauve or aniline purple), or it may be
from a carbonate or feeble combination of the said base, other purple coloring
matters of redder and also of bluer shades. To produce the redder colors the
mauveine is subjected to the action of the chloride, bromide, iodide, or other
salt of methyl, ethyl, propyl, butyl, amyl, ethylene, amylene, allyl, or other
organic radicals. I generally proceed in the following manner:-I take
mauveine (which is conveniently prepared by precipitating an alcoholic
solution of mauve with a large quantity of a dilute aqueous solution of caustic
potash or soda), and I mix the same with iodide of ethyl in the proportion of
twelve parts by weight of dry mauveine to ten parts of iodide of ethyl, and I
add also 60 or 70 parts of methylated spirit. I put the mixture into a strong
copper vessel capable of being very securely closed with a cover, which is
secured with screw bolts, and the joint is made tight by means of a vulcanized
india-rubber washer.
The vessel is then by means of a water bath kept at the temperature of
boiling water for 4 or 5 hours, and at the end of this time its contents
are mixed with methylated spirit, so as largely to dilute the product. I
find it convenient in practice to make the product from 2 lbs. of mauvene
into 14 gallons of commercial solution. After the addition of the required
quantity of spirit to reduce the strength to the desired extent, the solution is
filted and is ready for use. From a solution thus prepared the coloring
matter is not liable to be deposited on keeping, but from a strong solution the
coloring matter would be liable to crystallize out. If desired the coloring
matter may be prepared for the market by reducing it to a paste. For this
purpose I take the commercial solution and by the addition of a concentrated
solution of salt I throw down from it the color, and this, when collected on a
filter and drained to the desired extent, is the paste required. In employing
the color in dyeing and printing it will be found to work in the same way as
mauve.
The residue which is left on the filter in filtering the diluted product from
the converting vessel contains a mauve which may be extracted from it by
5 repeated boilings with spirit, and the mauveine may be precipitated to be again
worked by the addition of an excess of dilute caustic potash to the alcoholic
solution.
In producing the color the application of heat is not essential, although

page_text: very convenient, as it hastens the action, which, however, will go on slowly
if the substances are mixed and allowed to stand; light facilitates this
change.
The iodide of ethyl which I usually employ is made from methylated spirit,
and consequently contains iodide of methyl. An iodide made from fusel oil
may also conveniently be used, and such an iodide will be a mixture of the
iodides of several of the alcohol radicals above mentioned; or the iodide of
any one of them may be obtained and used separately, but this (except in the
case of methyl and ethyl) is expensive, and in no way advantageous. In place of
iodides of the organic radicals chlorides and bromides may be used, and nearly
if not quite as advantageously; other salts may also be used, but not I believe
advantageously, and some of them (as, for example, the acetates) have but
little or no action.
As respects other organic radicals besides those which I have mentioned by
name, and which are alcohol radicals, I have found with some of them
belonging to other classes that there is an action, but as far as I have found
the colors produced are not of commercial value, and I make no claim to the
use of salts of organic radicals other than those belonging to the various
alcoholic series.
Where in place of iodide of ethyl the iodide of another alcohol radical or
another salt of an alcohol radical is employed, the best proportions will not in
all cases be exactly those herein-before mentioned, but allowance should be
made for the difference in the combining numbers of the salts, but no great
accuracy is in any case required, as if a small excess be employed it may be
distilled off at the end of the converting process.
Another part of my Invention relates to the obtaining violet or bluer
colors from colors made as above described, To produce violet or bluer
colors the red purple color of my first process is treated with alkalies or
alkaline solutions. In practice I take the commercial solution of the red
purple, and boil it with an aqueous solution of potash containing about
5 per cent. of potash; the boiling is continued vigorously for 4 or 5
hours, and the coloring matter, which is in the form of a precipitate, is
collected on a filter and washed with water. Usually it hardly requires any
purification, But if necessary it may be purified by dissolving it in water
acidulated with acetic or other acid, and re-precipitating the clear solution
with alkali.
To make a commercial solution it is dissolved in methylated spirit, so that
about 14 gallons of solution may contain the product of 24 lbs. of mauveine.

page_text: This color also in printing and dyeing can be worked in the same way
as mauve.
In witness whereof, I, the said William Henry Perkin, have hereunto
set my hand and seal, this Sixth day of May, in the year of our
Lord One thousand eight hundred and sixty-four.
W. H. PERKIN. (L.S.)