CERTAIN IMPROVEMENTS FOR RENDERING TISSUES WATERPROOF
Year: 1855

page_text: LETTERS PATENT to Robert Paul-Coignet, Captain en Retraite du Génie,
of Rue du Bac, 42, Paris, France, and of 4, South Street, Finsbury,
London, for the invention of "CERTAIN IMPROVEMENTS FOR RENDERING
TISSUES WATERPROOF."
Sealed the 19th October 1855, and dated the 27th April 1855.
PROVISIONAL SPECIFICATION left by the said Robert Paul Coignet at
the Office of the Commissioners of Patents, with his Petition, on the
27th April 1855.
1, ROBERT PAUL COIGNET, Captain en Retraite du Génie, of Rue du
Bac, 42, Paris, France, and of 4, South Street, Finsbury, London, do hereby
declare the nature of my said Invention of "CERTAIN IMPROVEMENTS FOR
RENDERING TISSUES WATERPROOF" to be as follows, that is to say
My Invention consists in an improved composition for waterproofing
tissues.

page_text: White rosin
Norwegian. pitch
Bastennes pitch
Mutton fat
-
5 parts
5
10
10
4
2
"
"
Oil of schistus
25
Smoke black
1
23
Amber earth
3
33
Litharge
Alum
2
"
2
I mix the above substances to form the composition for rendering stuffs water-
proof in the following manner:-The fatty oils and resins are melted together,
and when reduced to a liquid state litharge is added by degrees whilst stirring
up the matters. After the said matters have remained on the fire about half
an hour at a temperature approaching ebullition, I add successively in the
following order the rest of the matters, viz', alum, amber earth, smoke black,
the whole being properly mixed by means of a wooden spatula.
My improved composition may be applied upon the tissues to be water-
proofed either in a hot or cold state, according to circumstances.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Paul Coignet in the Great Seal Patent Office on the
27th October 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
PAUL COIGNET, Captain en Retraite du Génie, of Rue du Bac, 42, Paris
France, and of 4, South Street, Finsbury, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of April, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her
reigu, did, for Herself, Her heirs and successors, give and grant unto me, the
said Robert Paul Coignet, Her special licence, that I, the said Robert Paul
Coignet, my executors, administrators, and assigns, or such others as I, the said
Robert Paul Coignet, my executors, administrators, and assigns, should atany
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 of "CERTAIN IMPROVE.

page_text: MENTS FOR RENDERING TISSUES WATERPROOF," upon the condition (amongst
others) that I, the said Robert Paul Coignet, by an instrument in writing
under iny hand and seal, 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 Robert Paul Coignet, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
My Invention consists in an improved composition for waterproofing textile
fabrics, and producing therewith an article capable of superseding leather
in its various applications where strength, suppleness, & impermeability are
required. Hitherto efforts have been made to cover fabrics in general with
hydrofuge coatings for the purpose of rendering them waterproof. These
fabrics may be divided into four classes.
First, fabrics requiring suppleness to be made into cloaks, aprons, medical
appliances, air cushions, &c., silk and cotton being the materials specially
employed for their manufacture, and caoutchouc and gutta percha forming the
principal ingredients of the waterproofing compositions.
Secondly, fabrics to which it is required to give impermeability and at the
same time a certain amount of rigidity, being intended to cover considerable
surfaces, such as tarred or oil cloths. They also receive a dressing to give
them a surface preparatory to the application of paints and varnishes. The
tarred canvasses are generally used for temporary or permanent coverings and
to insure impermeability in packing, and the oiled cloths for the coverings of
floors & furnature. Resins of different kinds dissolved in linseed oil forms
the base of the composition with which these fabrics are coated. The rigidity
which they possess is generally acquired at the expense of their flexibility, and
it is rarely that they fail to crack and scale off when put to the test.
Thirdly, fabrics rendered impermeable by means of the sulphates of copper or
iron. This process of recent Invention is principally adapted to vehicle covers.
Independent of its decreasing the strength of the fabrics, the salts retained in
the tissue are liable to be decomposed by rain water, and which in draining off
may give rise to serious accidents.
Fourthly, fabrics coated by means of a brush with siccative oil paints.
Besides the four classes of impermeable fabrics above described, the manu
facture, preparation, & applications of which are well known, there is a large

page_text: number of uses for which leather is employed, and which it may be replaced
with advantage & economy by fabrics, provided the following conditions are
fulfilled: First, that the fabrics present sufficient resistance to the wear &
tear to which they may be exposed. Secondly, that the composition with
which they are impregnated, while rendering them proof against hygrometric
influences, might remain unaltered in any of the atmospheric temperatures
to which they might be subjected. Thirdly, that the composition should
give to the threads of the fabric uniformity and adhesiveness, increasing
their strength and resistance, retaining, however, the necessary suppleness
and elasticity. These several results have been arrived at by the preparation
herein after described. Fabrics prepared with the said composition of flax,
hemp, cotton, and other textile materials, such as said cloths, ticking, and
felt, are capable of being substituted for leather for haruess padding, carriage
work, and articles of military equipment, requiring flexibility, such as the
trimmings of cavalry trowsers, straps & bands for machinery, washers for
joints of funnells & pipes, and the fittings of pumps, coverings of trunks
and portmanteaux, cards for carding machines, and embossed leather for
furniture and hangings. When the application for which the fabric is
intended requires a coating of varnish, it is necessary to employ a fabric
composed of fine threads, so as to avoid the employment of size, which would
render the surface liable to crack and scale off. When the fabric is required
in bands & strips 1 employ fabrics of the breadth and strength suitable to
their application.
COMPOSITION OF THE COATING.
Linseed oil, one hundred parts; thick oil of tar, twenty-five parts; galipot
oil, five parts; mineral pitch, two parts; white resin, five parts; Norwegian
tar, five parts; mutton suet, ten parts; oil of schistus, four parts; smoke black,
one part; amber earth, three parts; lithage, two parts; alum, two parts.
The fatty oil and resius are melted together, and when their liquefaction is
complete the litharge is added by degrees, and the whole stirred up. When
the whole has remained on the fire for about half an hour at a temperature
approaching ebullition, the other substances are incorporated with it in the
following order: Alum, amber earth, & smoke black, the whole being
completely mixed and stirred by means of a wooden spatula.. The mixture
thus prepared may be applied hot or cold, according to the purpose for which
the fabric is intended. The application of the composition is effected in the
usual manner; for narrow fabrics immersion may be resorted to, or by laying it
on frames, as usually practised. The smoke black and amber earth may be

page_text: suppressed and replaced by a double quantity of alum, and in like manner
the tar may be replaced by an equal quantity of galipo. The same result may
also be attained by applying an oil paint of a light color on the fabric covered
with the black composition.
I employ light fabrics prepared by the process above described for replacing
light stamped leathers employed for hanging and seats. I employ the said
compositions for waterproofing felts of any textile materials. The composition
may be applied by immersion, or simply with a brush, according to the degree
of penetration required.
And having now described the nature of my said Invention, and the manuer
of carrying the same into effect, I wish it to be understood that I do not
confine myself to the precise proportions or ingredients herein-before described,
reserving to myself the right of modifying the same; but what 1 claim is,
the preparation of a waterproofing composition & its application to various
fabrics for the production of a material susceptible of replacing leather in
various applications, as herein-before described.
In witness whereof, I, Robert Paul Coignet, have hereunto set my
hand and seal, this Twenty-fifth day of October, in the year of our
Lord One thousand eight hundred and fifty-five.
P. COIGNET. (L.B.)