IMPROVED METHODS OF AND PROCESSES FOR PRESERVING AND RENDERING IMPERVIOUS TO MOISTURE THREADS AND TISSUES OF HEMP, LINEN, COTTON, WOOL, AND SILK
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Edward Primerose Howard
Vaughan at the Office of the Commissioners of Patents, with his
Petition, on the 1st July 1875.-A communication from abroad by
François Hostelart, residing at Liège, in the Kingdom of Belgium.
I, EDWARD PRIMEROSE HOWARD VAUGHAN, F.C.S., of 67, Chancery
Lane, in the County of Middlesex, Patent Agent, do hereby declare
the nature of the said Invention for "IMPROVED METHODS OF AND PROCESSES
FOR PRESERVING AND RENDERING IMPERVIOUS TO MOISTURE THREADS AND TISSUES OF
HEMP, LINEN, COTTON, WOOL, AND SILK," being a communication to me from
abroad by François Hostelart, residing at Liège, in the Kingdom of
Belgium, to be as follows:-
This Invention consists in certain methods of treatment and processes,
having for their object the preservation of threads and tissues or fabrics
of hemp, linen, cotton, wool, and silk, and the rendering the same
more or less incapable of decomposition and impervious to moisture."
.. L
Assuming that it is desired to treat 25 kilogrammes of the materials
above mentioned in accordance with this Invention, the same are in the
first instance scoured by boiling in rain water for two hours, after
C

page_text: which they are removed from the vessel in which they have been boiled,
drained, and then put back into the boiler with 50 or 60 litres of fresh
water to which are added 500 grammes of caustic soda, and the whole then
boiled for two hours. The materials are then rinsed in fresh water and
exposed to the air at the temperature of from.35° to 40° cent., after
which they are steeped in a strong solution of alum for twenty-four
hours at the ordinary temperature. The materials are again rinsed in
water for the purpose of removing the unconsumed alum and then
dried.
A bath is prepared of rain water, in which are placed, when the same
is at the boiling point, from 10 to 25 parts of oak bark, 5 to 10 parts of
fustic, 3 to 8 parts of gambier, and 0.187 to 0.750 of bichromate of
potash, the proportion of water being 300 parts. The two first named
substances are well boiled together without the gambier, which is then
added and dissolved. The materials under treatment are then dipped
in the bath for a few seconds when the same is at the boiling point.
The bath is then allowed to cool to the ordinary temperature, and the
materials are agitated therein for a short time, until they are thoroughly
saturated with the liquid, care being taken to give access of air to the
vat or vessel employed. The materials are then dried in the shade
without rinsing, and the bichromate of potash is added to the bath in
the proportions above mentioned, and such mixture having been heated
to 40° or 50° cent., the materials are then passed through the bath and
afterwards rinsed. The materials are again removed and placed in a
wooden tub or receptacle, and containing water at the temperature of
40° to 50° cent., and having a solution of 2 per cent. of gluten or glue
added thereto. They are then allowed to remain for twenty-four hours
at the ordinary temperature, when the cover is lifted, the materials
dried, and if too stiff, dipped in water heated to 40° to 50° cent., in order
to remove the superfluous gluten or glue. The materials having
been dried will be found to have acquired the character of vegetable
leather.
In cases in which it is desired that the last described process shall
produce a still greater degree of imperviousness, the bath is formed of
200 parts of rain water, 4 parts of gluten or glue, 200 parts of linseed
oil, or a proportionate quantity of dissolved caoutchouc, and 15 parts of
tallow, adding 10 parts of lampblack or the same amount of ochre,
according as a dark or light tint is desired.

page_text: In the case of lampblack being employed it should be previously
calcined. The water and gluten or glue should be boiled, and the oil or
solution of caoutchouc and tallow then added, and the boiling continued
until, by means of constant stirring, the mixture is frothy, when it
should be stirred and gradually cooled. Fresh water should afterwards
be added by small degrees with continual stirring, until the mixture has
absorbed from 200 to 400 parts. The 4 parts of gluten or glue may be
replaced by 12 parts of fecula or starch, to be applied in a similar
manner as the gluten or glue, but the result will not be equally good so
far as flexibility and elasticity are concerned.
In the case of woven tissues or fabrics the following process is
adopted, although any suitable arrangements may be employed :-The
fabric is rolled on a cylinder which is placed before a table provided
with two guides, between which the fabric passes and unrolls itself.
The fabric in leaving the table descends into a trough containing the
coating or saturating preparation, passes between napping brushes, and is
submitted to a mangle consisting of two cylinders, the upper one of
which has a copper surface. The surfaces of the cylinders are polished
and the upper one is pressed against the lower one by means of weights,
as will be well understood. The fabric continuing its way passes between
additional brushes, and rolls itself upon a cylinder provided for that
purpose. The coating or saturating composition is placed in the trough
and heated by means of steam, the temperature being regulated by the
agency of a cock.
Any suitable arrangements, such as will be well understood by persons
conversant with mechanism, may be used for removing the fabric from
the trough, and the whole machine may be worked by any suitable
motive power and mechanical appliances.