AN IMPROVED PROCESS OF DYEING SILK, WOULLEN, CUTton, and OTHER FABRICS.
Year: 1875

page_text: LETTERS PATENT to Jean Baptiste Charles Henri Petitdidier, of St.
Denis (France), Dyer, for the Invention of "AN IMPROVED PROCESS
OF DYEING SILK, WOULLEN, CUTton, and OTHER FABRICS.
Sealed the 20th July 1875, and dated the 25th March 1875.
PROVISIONAL SPECIFICATION left by the said Jean Baptiste Charles
Henri Petitdidier at the Office of the Commissioners of Patents,
with his Petition, on the 25th March 1875.
I, JEAN BAPTISTE CHARLES HENRI PETITDIDIER, of St. Denis
Þ (France), Dyer, do hereby declare the nature of the said Invention
for "AN IMPROVED PROCESS OF DYEING SILK, WOOLLEN, COTTON, AND OTHER
FABRICS," to be as follows:-
My Invention has for its object an improved process for dyeing silk,
either in the raw state or in piece, and either alone or mixed with wool
or cotton, or with both wool and cotton.

page_text: my Invention I employ in place of water either alcohol, benzine, spirit
of turpentine, sulphuret of carbon, ether or wood spirit, as the solvent.
or vehicle in which the coloring matter is dissolved for dyeing the
silk or mixtures of silk with wool or cotton, as I have found that
these liquids do not have the deteriorating effect upon the silk that
water has.
As mordants for the dyes prepared with the said solvents I employ
resins which are soluble therein, and which mix readily with the coloring
matter, and allow the same to be taken up by the silk. After steeping
in the dye bath the silk is dried, and the colour is then fixed on the tissue
by the application of steam, after which the resinous matter is removed
from the silk by passing it several times through a bath of benzine.
As a suitable mordant I employ about 6lbs. of resin with about
3 ounces of stearic acid dissolved in about 7 pints of benzine.
For preparing the dye solution I take any suitable known colouring
matters, such as aniline colours or vegetable lakes, which I dissolve in
any of the before-mentioned solvents; this solution is mixed with the
dissolved mordant in proportions depending on the depth of tint required,
and is placed in a vat so arranged that the tissue in passing between two
cylinders covered with caoutchouc will take up the colouring matter
uniformly.
After drying and steaming, as before described, the tissue is passed
through three baths of benzine for dissolving the fatty and resinous
mordant, after which the fabric is finished in the usual way and
folded.
If instead of silk tissues in piece, cut lengths of raw silk have to be
dyed these are passed one by one between the two before-mentioned
cylinders, one of which is immersed in the bath, and the process is
carried out as described above for dyeing the silk tissue in piece. The
same process is also applicable for dyeing or reviving faded dresses or
pieces of silk, as also for reviving silk tapestry. The latter is offected
by applying the dye solution above described by means of a brush, for
which purpose I thicken the resinous mordant sufficiently to prevent it
from running or spreading; this may be effected by the admixture of
tallow, wax, spermacetti, or by using an excess of the stearic acid.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Jean Baptiste Charles Henri Petitdidier in the
Great Seal Patent Office on the 6th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEAN
BAPTISTE CHARLES HENRI PETITDIDIER, of St. Denis (France), Dyer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of March, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Jean Baptiste Charles Henri
Petitdidier, Her special license that I, the said Jean Baptiste Charles
Henri Petitdidier, my executors, administrators, and assigns, or such
others as I, the said Jean Baptiste Charles Henri Petitdidier, my exe-
cutors, administrators, 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 Invention for "AN IMPROVED
PROCESS OF DYEING SILK, WOOLEN, COTTON, AND OTHER FABRICS," upon the
condition (amongst others) that I, the said Jean Baptiste Charles Henri
Petitdidier, 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 Jean Baptiste Charles Henri
Petitdidier, 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 thereof, that is
to say :-
My Invention has for its object an improved process for dyeing silk,
either in the raw state or in niece and either alone or mixed with wool

page_text: from running or spreading; this may be effected by the admixture of
tallow, wax, spermacetti, or by using an excess of stearic acid.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I claim,-
First. The use for dyeing silk and other tissues of a fatty or resinous
mordant in combination with dye stuff dissolved in alcohol or other
suitable spirit, so as to constitute a dye bath of coloured resinous or fatty
matter, substantially as herein described.
Second. Fixing the dye applied in the manner above referred to by
means of steam, and discharging the resinous or fatty vehicle by repeated
immersion in benzine, substantially as herein described.
In witness whereof, I the said Jean Baptiste Charles Henri
Petitdidier, have hereunto set my hand and seal, this Fifth day
of August, in the year of our Lord One thousand eight hundred
and seventy-five.
JEAN BAPTISTE CHARLES HENRI PETITDIDIER. (L.S.)
Witness,
CHARLES FROSSARD,
23, Boulevard de Strasbourg,
à Paris.