IMPROVEMENTS IN TREATING CANVAS AND OTHER WOVEN FABRICS TO PRE- SERVE THE SAME FROM ATMOSPHERIC AND OTHER DESTRUCTIVE INFLUENCES OR CAUSES
Year: 1875

page_text: ETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN TREATING CANVAS AND OTHER WOVEN FABRICS TO PRE-
SERVE THE SAME FROM ATMOSPHERIC AND OTHER DESTRUCTIVE INFLUENCES OR
CAUSES." A communication from abroad by Henri Nicolas Rogé,
Edouard Poret, Pierre Hypolite Baffoy, and Pierre Stanislas
Eléonore Dupré, all of Paris, France.
Sealed the 13th July 1875, and dated the 25th January 1875.
FROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 25th January 1875.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County
of Middlesex, Patent Agent, do hereby declare the nature of the
OTHER WOVEN
said Invention for "IMPROVEMENTS IN TREATING CANVAS AND
FABRICS TO PRESERVE THE SAME FROM ATMOSPHERIC AND OTHER DESTRUCTIVE
INFLUENCES OR CAUSES," to be as follows:-
This Invention relates to an improved method of preserving cloth or
canvas used for cart tilts, tents, sails, wrappers, or coverings, and
Price 8d1

page_text: generally all kinds of fabrics exposed to the action of air or moisture,
and liable to deterioration from these or other causes of a like nature.
In order to preserve such fabrics they have hitherto been impregnated
with certain metallic salts, the salt usually employed being the sulphate
of copper, which has however the objection of burning the fibres of the
fabric.
The present Invention consists in the use for preserving canvas and
other fabrics generally, of salts of lead and all products derived from
lead, which have never hitherto been applied for the above purpose,
although they possess highly preservative qualities, and combine in an
insoluble state with the vegetable fibres, besides imparting thereto their
special properties without impairing their strength and elasticity as
when salts of copper are used. The canvas when impregnated with lead
is rendered impervious to moisture and preserved from the oxidizing
influence of the air, as well as from attacks of parasitic insects or
cryptogamic vegetation, organic life being incapable of existence in the
presence of lead.
Any method or process known to chemists or manufacturers may be
employed for fixing the lead, whether in the form of salt, an oxide,
or in a metallic state, one or two examples only being here given. For
instance, the same means may be employed as are now used by dyers
for fixing oxide of lead or other compound of lead in fabrics, viz., a
solution of plumbale of lime, such as used in dyeing and calico printing.
The lead may also be fixed by immersing the fabrics in solutions of its
salts; for example, the nitrate, acetate, sub-acetate, and others, and
then passing them through either a soap, soda, or lime bath, or through
solutions of soluble carbonates, sulphates, silicates, sulphurets, chro-
mates, or others capable of precipitating lead solutions.
When salts of lead formed with organic acids are employed they may
be fixed by the action of the air only, or when said salts are formed
with pyroligneous acids the tarry matters contained in these products
will aid in preserving the canvas.
Another method of fixing the lead in the fabrics consists in immersing
the same in a solution of double hyposulphite of lead and of soda, in
which case the lead becomes transformed into sulphuret, which com-
bines with the fabric.

page_text: The fabrics prepared by one or other of these means may either be
allowed to retain the color which they thus acquire, or they may be
dyed of any color by taking advantage of the reaction of the salts or
oxides of lead in the presence of coloring matters, in which case it is
simply necessary to pass the fabric through a decoction of dye wood or
other tinctorial preparations.
-
The following is an example of the process of impregnation of this
Invention For 100 lbs. of fabric I dissolve, in a sufficient quantity of
water to cover the same, 10 lbs. of acetate of lead, and steep the cloth
for 10 or 12 hours in this solution, which is, by preference, kept heated.
The cloth is then passed through wringing rollers or their equivalent,
and afterwards immersed in a solution containing 10 lbs. of silicate of
soda, sirupy at 45°; it is then rinsed and dyed if desired. The propor-
tions named may be varied according to the quality of the goods
treated, and any other substances forming insoluble lead compounds
may be employed.
The Invention consists therefore in the particular employment of
lead, fixed, combined, or mixed more or less intimately with the fibres
of the fabric in an insoluble state for preserving canvas or other cloth
exposed to the action of the atmosphere or inclemency of the weather,
the humidity of the earth or of buildings, the attacks of parasites, or
other such like causes of destruction.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent
Office on the 24th July 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COMF, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of January, 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 successors, give
and grant unto me, the said Alexander Melville Clark, Her special licence
that I, the said Alexander Melville Clark, my executors, administrators,

page_text: and assigns, or such others as I, the said Alexander Melville Clark,
my executors, administrators, and assigns, should at any time agree
with, and 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 Inven-
tion for "IMPROVEMENTS IN TREATING CANVAS AND OTHER WOVEN FABRICS TO
PRESERVE THE SAME FROM. ATMOSPHERIC AND OTHER DESTRUCTIVE INFLUENCES OR
CAUSES," a communication to me from abroad by Henri Nicolas Rogé,
Edouard Poret, Pierre Hypolite Baffoy, and Pierre Stanislas Eléonore
Dupré, all of Paris, France, upon the condition (amongst others)
that I, the said Alexander Melville Clark, my executors or admi-
nistrators, 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 Alexander Melville Clark, 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 (that is to say):-
This Invention relates to an improved method of preserving from
decay cloth or canvas used for cart tilts, awnings, tents, sails, wrappers,
or coverings, and generally all kinds of fabrics exposed to the action of
air or moisture, and liable to deterioration from these or other causes
of a like nature.
In order to preserve such fabrics they have hitherto been impregnated
with certain metallic salts, the salt usually employed being the sulphate
of copper, which has however the objection of destroying the fibres of
the fabric.
[
The present Invention consists in the use for preserving canvas and
other fabrics generally of salts of lead, and all products derived from
lead, which have never hitherto been applied for the above purpose,
although they possess highly preservative qualities, and combine in an
insoluble state with the vegetable fibres, besides imparting thereto their

page_text: special properties without impairing the strength and elasticity of the
fibres as when salts of copper are used. The canvas when impregnated
with lead is rendered impervious to moisture, and preserved from the
oxidizing influence of the air, as well as from the attacks of parasitic
insects or cryptogamic vegetation, it not being possible for organic life
to exist in the presence of lead.
Any method or process known to chemists and manufacturers may be
employed for fixing the lead, whether in the form of a salt, an oxide, or
in a metallic state, one or two examples only being here given. For
instance, the same means may be employed as are now used by dyers
for fixing oxide of lead or other compound of lead in fabrics. Thus I
may employ a solution of plumbate of lime, such as used in dyeing
and calico printing. The lead may also be fixed by immersing the
fabrics in any suitable solution of its salts; for example, the nitrate,
acetate, sub-acetate, and others, and then passing them through either
a soap, soda, or lime bath, or through solutions of soluble carbonates,
sulphates, silicates, sulphides, chromates, or other substances capable of
precipitating lead solutions.
•
When salts of lead formed from organic acids are employed they may
be fixed by the action of the air only. When said salts are formed with
pyroligneous acids the tarry matters contained in these products will
aid in preserving the canvas.
Another method of fixing the lead in the fabrics consists in immersing
the same in a solution of double hyposulphite of lead and soda, in which
case the lead becomes transformed into sulphide, which combines with
the fabric.
The fabrics prepared by one or other of these means may either be
allowed to retain the color which they thus acquire, or they may be dyed
of any color by taking advantage of the reaction of the salts or oxides
of lead in the presence of coloring matters, in which case it is simply.
necessary to pass the fabric through a decoction of dye wood or other
tinctorial preparation.
The following is an example of the process of impregnation of this
Invention: For 100 lbs. of fabric I dissolve in a sufficient quantity of
water to cover the same, 10 lbs. of acetate of lead, and steep the cloth
for 10 to 12 hours in this solution, which is, by preference, kept heated.

page_text: The cloth is then passed through wringing rollers or their equivalent,
and afterwards immersed in a solution containing 10 lbs. of silicate of
soda, sirupy at 45°; it is then rinsed and dyed if desired. The pro-
portions named may be varied according to the quality of the goods
treated, and any other substances forming insoluble lead compounds 5
may be employed.
The above treatment may also be applied for the preservation of
cables, ropes, and cordage used for ships and other purposes, as well
Fabrics
as to string, twine, and all kinds of threads and yarns.
woven from threads which have been so treated with salts of lead will
be thus rendered impervious and proof against decay. Yarns or cords
thus prepared may be used for the manufacture of bands or straps of
webbing.
The preservative treatment may either be applied to the cable, rope,
cordage, twine, or thread in a manufactured condition, or to the
filaments, whether hemp, flax, jute, or other material, of which they
are composed.
Having described the nature of the Invention, and the manner of
performing the same, I declare that what I claim as the Invention to be
protected by the herein-before in part recited Letters Patent is, the
application and employment of lead fixed in an insoluble state in or
combined with the fibres of filamentous and fextile materials for pre-
serving the same from decay, as specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Twenty-third day of July, in
the year of our Lord One thousand eight hundred and seventy-
five
A. M. CLARK: (L.S.)