CERTAIN PROCESSES FOR INCREASING ON MANUFACTURED FABRICS THE SEVERAL SHADES OF INDIGO
Year: 1851

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, VICTOR
HYACINTHE LIBERT GUILLOUET, of Condé sur Noirot, Calvados, in the Republic
of France, Chemist, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Tenth day of March,
One thousand eight hundred and fifty-one, in the fourteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Victor Hyacinthe Libert Guillouet, my exors, adñiors, and assigns, Her
especial license, full power, sole privilege and authority, that I, the said
Victor Hyacinthe Libert Guillouet, my exors, adñiors, and assigns, or such
others as I, the said Victor Hyacinthe Libert Guillouet, my exors, adññiors, or
assigns, should at any time agree with, and no others, from time to time and
at all times during the term of years therein expressed, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, and in the Islands of Jersey, Guernsey, Alderney,
Sark, and Man, and also in all Her said Majesty's Colonies and Plantations
abroad, my Invention of "CERTAIN PROCESSES FOR INCREASING ON MANUFACTURED
FABRICS THE SEVERAL SHADES OF INDIGO;" in which said Letters Patent is con-
tained a proviso that I, the said Victor Hyacinthe Libert Guillouet, shall
cause a particular description of the nature of my said Invention, and in what
manner the same is to be performed, by an instrument in writing under my

page_text: hand and seal, to be inrolled in Her said Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said in
part recited Letters Patent, as in and by the same, reference being thereunto
had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Victor Hyacinthe Libert Guillouet, do hereby declare that the nature of my
said Invention, and in what manner the same is to be performed, are fully
described and ascertained in and by the following statement thereof, that is
to say :-
My Invention consists in subjecting textile fabrics dyed with indigo to the
action of an elevated temperature under steam pressure.
Indigo is a substance naturally insoluble, and to fix it on textile fabrics it
is necessary to render it soluble, which is effected by means of desoxigenating
agents, such as sulphate of iron and oxyde of calcium. Then, by immersing
the textile fabrics in the solutions thus obtained, and dipping them during the
requisite time, shades of colour varying from the lightest to the deepest hues
are obtained. One of the distinctive characters of indigo is its volatile pro-
perty, which principle I make available by operating in the following manner:
I subject the fabrics to the action of an elevated temperature under a
certain pressure obtained by water steam in a metallic vessel closed air tight,
and capable of resisting the pressure exerted and necessary for combining
more intimately the colouring molecules of the indigo with the fibres of the
textile fabrics, and modifying at the same time the primitive arrangement of
its molecules. By these means I increase the tone of shade, and cause it to
reflect the blue violet ray. The form of the apparatus employed, which is
provided with a proper cover, is unimportant; it may be round, square, or
oblong; the result will be the same, videlicet, the modification of the indigotine,
which will acquire a deeper and more violet shade. 1 obtain the shade by
means of pressure, varying from one to six atmospheres and even more. The
apparatus must always be provided with at least one safety valve, and have at
its upper extremity a cock for the expulsion of the internal air; that cock
must be kept open during a few minutes, when the steam is introduced into
the apparatus, as herein-after described; a discharge cock must be adapted to
the bottom of the apparatus, and left open a little during the operation to
allow egress of the condensed steam. I set a wooden frame at about eight
inches from the bottom of the apparatus, on which are superposed in a flat
position the fabrics which are to be operated upon, and which may be to the
number of twenty-five to thirty pieces, according to the capacity of the
metallic vessel. This arrangement being completed, the whole is covered

page_text: with woollen blankets to avoid the contact of the fabrics with the sides of the
apparatus, and also to absorb the first vapours. The apparatus is then closed
air tight, and steam is admitted by a tap through brass pipes placed under
the frame and pierced with the smallest possible holes in order to obtain a
more regular distribution of steam. By these means the steam passes through
the whole of the fabrics, and exerts on them an equal tension in every
direction, and in the course of twenty. to thirty minutes the desired coloring
effect is produced, the cock which admits the steam is closed, and the discharge
cock is entirely opened. I then raise the lid of the apparatus, which is left to
cool during fifteen to twenty minutes; the goods being taken out require only
to be folded, which operation should be effected immediately, their hygrometric
condition being then in the most suitable condition.
The result of the above-described operation is a sensible diminution in the
length or warp, but an insensible diminution in the width of the fabrics, which
are rendered much closer, thicker, and smoother. By my processes I super-
sede with great advantages all kinds of dressing generally employed, which are
defective for their want of stability. I increase the thickness and softness of
the fabrics at the same time that I increase the coloration, these effects being
simultaneous and inseparable, and are the natural and unassisted results of
one single operation.
My processes are applicable to the treatment of every kind of fabric con-
taining indigo dye, without reference to the pattern or design; the indigo
shade will acquire the qualities above described, without affecting the other
colours or shades of colours with which it is combined, on the contrary
the latter will become brighter. It will be easily understood from what I
have herein-before described, that the chemical action between the molecules
of indigo and the fibres of the tissues gives rise to their more intimate union,
and that the physical effects produced by the elevation of temperature and
tension of the aqueous vapours act on the colouring molecules in a similar
manner, that is to say, they swell the fabrics by the separation and distension
of their pores, the result of which is a closer and thicker fabric possessing
greater softness.
And having now described the nature of my Invention, and the manner of
putting the same into operation, I wish it to be understood that I do not
confine myself to the precise details herein-before described, provided the
general features be preserved for carrying out my said Invention, nor do I lay
claim to the apparatus herein described; but what I do claim as my Inven-
tion, and intended to be protected by the said in part recited Letters Patent,
is, the subjecting textile fabrics dyed with indigo to the action of an elevated

page_text: temperature under steam pressure for increasing the shades of indigo in the
said fabrics, as herein-before described.
In witness whereof, I, the said Victor Hyacinthe Libert Guillouet, have
hereunto set my hand and seal, this Thirtieth day of August, in the
year of our Lord One thousand eight hundred and fifty-one.
VICTOR HYACINTHE LIBERT (L.s.) GUILLOUET.
Taken and acknowledged by Victor
Hyacinthe Libert Guillouet (party
hereto), at Paris, in the Republic
of France, this 30th day of August,
This is the Specification marked A. referred to in the Affidavit of Paul
Richond, sworn before me this 9th day of September, 1851..
HENRY MOWBRAY.
Paul Richond, of 4, South Street, Finsbury, in the County of Middlesex,
Gentleman, maketh oath and saith that he is acquainted with the manner and
character of the handwriting of "Thomas Pickford," Her Britannic Majesty's
Consul at Paris, in the Republic of France. And this deponent further saith,
that the signature "Thomas Pickford" set, subscribed, or written in the
margin of the Specification hereunto annexed marked A., and dated the
Thirtieth day of August ultimo, and purporting to be executed by Victor
Hyacinthe Libert Guillouet, of Condé sur Noirod, Calvados, in the Republic of
France, Chemist, whereby it is stated that tho Specification was acknowledged
by him, the said Victor Hyacinthe Libert Guillouet, before the said "Thomas
Pickford," on the said day of August, in Paris aforesaid, is of the proper
handwriting of the said "Thomas Pickford."

page_text: AND BE IT REMEMBERED, that on the oath of Paul Richond, the
Specification aforesaid was enrolled word for word as above written. And
also the Specification aforesaid was stamped according to the tenor of the
Statute made for that purpose.
Enrolled the Ninth day of September, in the year of our Lord. Onc
thousand eight hundred and fifty-one.