IMPROVEMENTS IN BLEACHING JUTE FIBRE
Year: 1863

page_text: LETTERS PATENT to George Stuart, of Glasgow, in the County of
Lanark, North Britain, Commission Merchant, for the Invention of
"IMPROVEMENTS IN BLEACHING JUTE FIBRE."
Sealed the 18th September 1868, and dated the 25th March 1868.
PROVISIONAL SPECIFICATION left by the said George Stuart at the
Office of the Commissioners of Patents, with his Petition, on the 25th
March 1868.
I, GEORGE STUART, of Glasgow, in the County of Lanark, North Britain,
5 Commission Merchant, do hereby declare the nature of the said Invention
of "IMPROVEMENTS IN BLEACHING JUTE FIBRE," to be as follows, that is to
say:
This Invention relates to the bleaching of jute fibre, either in its unmanu-
factured state, or in rags, paper pulp, or other more or less manufactured form,
O and has for object to obtain an improved effect with a lessened risk of injury
to or excessive action on the fibre.
The Invention consists in steeping the jute a number of times alternately

page_text: in a cold dilute solution of a chloride, such as the chloride of lime, and in
a cold dilute solution of sulphuric acid. When necessary for the removal
of impurities, the jute may be subjected to ordinary cleansing processes, but,
with the exception of being thoroughly washed in cold water between each
steeping, the jute is not to be subjected to any further bleaching process.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Stuart in the Great Seal Patent Office on the
23rd September 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
STUART, of Glasgow, in the County of Lanark, North Britain, Commission
Merchant, 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 sixty-three, in the twenty-sixth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said George Stuart, Her special licence, that I, the said Georgo
Stuart, my executors, administrators, and assigns, or such others as I, the
said George Stuart, my executors, administrators, or 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 "IMPROVEMENTS IN
BLEACHING JUTE FIBRE," upon the condition (amongst others) that I, the
said George Stuart, my exccutors 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 George Stuart, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed; to be particularly described and ascertained in and by the following
statement in writing, that is to say :-
My said Invention relates relates to the bleaching of jute fibre, either in its
unmanufactured state, or in rags, "half-stuff," paper pulp, or other more or

page_text: less manufactured form, and has for object to obtain an improved effect with
a lessened risk of injury to or excessive action on the fibre.
And my said Invention consists in steeping the jute a number of times
alternately in a dilute solution of a chloride, such as the chloride of lime, and
in a dilute solution of sulphuric acid.
In practising my said Invention according to one modification, the jute,
having if necessary been washed with alkali to remove grease or other inpuri-
ties, is first immersed in a solution of chloride of lime, which may be of a
strength marking from three to four degrees of Twaddell's hydrometer, and in
this solution it is kept during six to eight hours, or longer if it is not found to
be weakened. The solution having been drained or squeezed out of the jute,
the jute is washed in pure water, and then subjected to a first immersion
in dilute sulphuric acid of a strength of about six degrees. The jute may
continue immersed in the acid for from six to twelve hours; the acid is then
drained or squeezed out of it, and it is washed in pure water. The jute is
then immersed a second time in a solution of chloride of lime, which may be a
little weaker than for the first immersion, say from two and a half to three and
a half degrees, and in this solution it may remain for from four to six hours.
After being drained or squeezed and washed as before, the jute is immersed a
second time in dilute sulphuric acid of about the same strength as before,
remaining immersed for three or four hours, and being thereafter drained or
squeezed and washed. If the jute is not then white enough it is immersed a
third time in a solotion of chloride of lime marking two to three degrees, or a
little weaker than before, and after being drained or squeezed and washed
is immersed a third time in the acid, being finally drained or squeezed and
washed. The practical bleacher or paper maker will understand that the
strengths of the solutions and the durations of the steepings may require to be
varied somewhat to suit the various conditions and qualities of jute under
treatment, but the proportions given will be found to answer well in ordinary
cases.
Having thus particularly described my said Invention, and the manner in
which the same is or may be performed, I have to state that I do not restrict
myself to the precise details herein-before described, and that I do not claim
the bleaching of jute by a single immersion in a chloride solution and a
single immersion in dilute sulphuric acid, but that what I believe to be novel
and original, and claim as the Invention secured to me by the herein-before
in part recited Letters Patent, is,―
The bleaching of jute fibre by immersing it twice or oftener in a solution of

page_text: a chloride, each such immersion being followed by an immersion in dilute
sulphuric acid, substantially as herein-before described.
In witness whereof, I, the said George Stuart, have hereunto set my
hand and seal, this Twenty-second day of September, in the year of
our Lord One thousand eight hundred and sixty-three.
Witness,
EDMUND HUNT,
Patent Agent,
28, St. Enoch Square,
Glasgow.
GEORGE STUART. (L.B.)