IMPROVEMENTS IN THE PROCESS OF EXTRACTING THE FIBRES FROM TEXTILE PLANTS, AND ESPECIALLY THOSE OF THE URTICA FAMILY
Year: 1880

page_text: LETTERS PATENT to George Vian, of No. 1, Rue Laffitte, France, for an
Invention of "IMPROVEMENTS IN THE PROCESS OF EXTRACTING THE FIBRES
FROM TEXTILE PLANTS, AND ESPECIALLY THOSE OF THE URTICA FAMILY.”
A communication by Paul André Arthur Marie Auguste Favier, of Paris,
France.
PROVISIONAL SPECIFICATION left by the said George Vian at the Office
of the Commissioners of Patents on the 20th April 1880.
GEORGE VIAN, of No. 1, Rue Laffitte, France. "IMPROVEMENTS IN THE PROCESS
OF EXTRACTING THE FIBRES FROM TEXTILE PLANTS, AND ESPECIALLY THOSE OF
THE URTICA FAMILY." [A communication by Paul André Arthur Marie Auguste
Favier, of Paris, France.]
According to this Invention the stems of the textile plants, either freshly cut or
a short time after being cut, are subjected to the action of heat. For this purpose
they are enclosed in a vessel into which steam or hot air or gases are admitted.
The time of exposure should be proportional to the time elapsed between the
cutting of the stems and the beginning of the treatment. After having been left
in the high temperature for a sufficiently long time the stems are taken out and
the exterior cortical parts can then be stripped or drawn off easily, all the useful
fibres adbering thereto, and being thus maintained perfectly parallel with each
other. The bands thus stripped off are then a second time exposed to a temperature
considerably higher than previously. For this purpose super-heated steam or
sufficiently heated air or gases are used, and after this second exposure the fibres are
drawn off from the bands of cortical matter, the resinous substance by means of
Thus the
which they adhered thereto remaining almost all on the latter.
fibres are obtained ready for the heckling or combing machine without having gone
through the ordinary operations of retting and breaking, and they are left perfectly
parallel whereby the great waste of material generally produced by the following
operations is avoided.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George Vian in the Great Seal Patent Office on the 19th October
1880.
GEORGE VIAN, of 1, Rue Laffitte, France.
"IMPROVEMENTS IN THE PROCESS
OF EXTRACTING THE FIBRES FROM TEXTILE PLANTS, AND ESPECIALLY THOSE OF
THE URTICA FAMILY." A communication by Paul André Arthur Marie Augusto
Favier, of Paris, France.
The means generally employed since the remotest times for extracting the useful
fibres from textile plants consist in retting.
In examining a stem of flax or jute or of china grass it will bo found that the 1
textile fibres adhere on the inner ligneous parts or awn or boon by means of a gum
like resinous substance, which also glues the fibres together. This adhesive
substance, which is generally known under the name of pectase, is insoluble, and
the object of the retting is to transform it into a soluble pectine so as to cause the
separation of the fibres from the awn and from the cortical matter enclosing them 1
and at the same time the separation of the fibres from each other.
The retting which is a source of serious danger to the public health in the
localities where it is practised, is a difficult operation as it requires much hand
labor, and if not properly managed it is liable to deteriorate the textile fibres. As
regards hemp and flax the process can be performed in a reliable manner, but this 2
is not the case with the thick stems of jute, the under part of which is hardly
retted when the fibres of the upper end are already injured; this explains the
difference in the resistance that is met with in the fibres of this textile material.
This operation is impracticable for china grass in which the fibre is buried in a
considerable mass of gum like resinous substance. The result thereof is that
during the retting certain parts of the fibre adhere still to the awn whilst others
are already injured.
It is a matter of astonishment that the very foundations of such considerable
manufactories remain based on empiricism instead of on a solid scientific basis,
all the more so that retting is almost impossible in hot countries, and even in 3
the most favorable conditions it never results in a complete transformation of the
pectase into soluble pectine, thus entailing the necessary subsequent observation
called packing, packling, and picking, in order to obtain the complete separation of
the useful fibres from the awn or boon.
Experiments that I made with regard to the utilization of china grass (urtica 3
utilis) indicated that the retting process is a failure, whilst the use of any of the
existing machines for decorticating this plant either in its green or its dried state
proved equally abortive. China grass whether green or dry is such a voluminous
material that it must of necessity be cut up on the spot. All the machines which
treat the plant in the dry state require that its stems be previously dried in an 4
oven; this operation can be effected without much difficulty in factories, but it is
not possible in the open country. Machines operating on the green plant do not
yield over 50% of the fibres it contains when the decortication is effected
immediately after the cutting, but should eight days elapse between these two
operations the yield is altogether insignificant.
The desideratum sought for was clearly laid down by the Indian Government
offering vainly, as far back as 10 years ago, a prize of £5,000 for a machine or
process for decorticating china grass in its green state, that is, first, for separating
the awn from its cortical envelope; and, second, for separating the fibres from the
gummy resinous matter surrounding them. It struck mo that this result could be
obtained by dividing it, and after a few experiments I succeeded completely.
By subjecting the stems of china grass, which may be cut 8 days previously,

page_text: in a closed vessel to the action of heat I have obtained a complete separation
of the awn from the cortical envelope, which latter contains the entire quantity of
useful fibres, the proof of which is that on breaking the former no traco of fibrous
material can be found.
In practice I heat the china grass stems to the requisite temperature by
injecting steam, hot air, or hot gases into a vessel containing the china grass stems.
When the necessary quantity of water can be easily procured steam may be
used for this purpose. In this case the apparatus consists essentially of a small
easily portable steam boiler with a comparatively large fire box to facilitate the
burning of the awn.
Suitably arranged pipes conduct the steam into large wooden receptacles in
which the stems are placed as fast as they are cut. Each complete apparatus
should have at least three such receptacles, one of which receives the steam, whilst
the second is being filled with stems, and the third is being emptied. As soon as
the steam begins to escapo through the joints of the receptacle the operation is
finished, providing that the china grass is freshly cut. But the treatment should be
kept up longer in proportion to the time elapsed since the cutting if the latter has
been effected eight days or more.
The stems having thus been subjected to the action of the steam the bark is
separated from the awn, which operation is so easy that it can be performed by
children without difficulty. One child of 10 to 12 years can, in one day, easily bark
off 250 to 300 kilogrammes of green stems, rendering the cortical envelope in the
form of long strips or bands which contain the entire quantity of fibres enclosed in
the stems, and these fibres are maintained perfectly parallel whereby the succeeding
combing is greatly facilitated.
As the expense of fuel is absolutely nought, because the awn is used as com-
bustible, it can be easily seen at what small cost a ton of green china grass can bo
decorticated. The steam does not change in any way the nature of the gummy
resinous substance surrounding the textile fibre and which attaches the latter to
the awn, its use does not constitute therefore a peculiar method of retting,
it forms only a simple means of rapidly subjecting the stems to a determined
temperature.
Under the influence of this temperature the water contained in the stems tends to
evaporate and causes thereby the separation of the awn from its cortical envelope.
The gummy resinous substance is in no ways modified and the strips or bands
contain the entire quantity of textile fibres and the entire mass of this resinous
substance surrounding them. When water cannot be easily procured the same
result can be obtained by using hot air instead of steam.
I have found that this same process is also applicable to flax, hemp, jute, etc.
The fibres of all these textiles can be obtained in the shape of bands containing the
entire quantity of useful fibres without the slightest trace of awn, these fibres
being thus maintained perfectly parallel.
These bands can consequently be subjected directly to the action of the combing
machine without having gone through the preparatory operations of breaking and
retting. The fibres being maintained perfectly parallel the waste produced in the
combing will be absolutely insignificant, whilst with the processes heretofore
employed the waste amounts often to 50° and even more.
Од
The bands of china grass obtained by the preceding operation contain too largo
a quantity of gum to admit of being combed immediately with economy.
examining a stem of china grass there will be found first on the awn a layer of gum,
then the textile fibres, and then a second layer of gum thicker than the first, and
finally the exterior brown bark. My experiments have shown that it is possible
to separate these different concentric layers so that the useful fibres can simply
be drawn out of its envelopes. This is effected either by leaving the stems for a
longer period exposed to a temperature of a little more than 100° centigrade,
or by elevating this temperature, which is of course a more practical and more
rapid means.

page_text: For freshly cut stems a temperature of about 150° centigrade should be used, but
this temperature should be raised in proportion with the length of timo intervening
between the cutting and the treatment.
The most practical method to rapidly expose the stems under treatment to the
desired temperature consists in employing as vehicle of the heat, superheated
steam, or air, or gases heated to the proper temperature, and which are injected
into the receptacle containing the stems.
The stems to be treated by this process are placed in wooden cases in which
'they are subjected to the action of the superheated steam or hot air, according to
the special circumstances. They are then passed over to children who separate the
awn from the cortical envelope and then separate the different parts of this
envelope and obtain the useful fibre by simply drawing it off.
The latter operation can also be effected mechanically by means of a brush.
Thus the useful fibres are obtained in the shape of bands free from the exterior
brown bark and from a part of the gum. These bands contain the entire quantity
of the fibres all perfectly parallel with each other. They are now ready to be
combed and transformed into heckeled flax.
I thus suppress the retting and breaking operations and consequently the loss of
raw material which is the unavoidable result of these same.
This process can equally be used to separate the constituent parts of plants
which have no internal awn like phormium tenax, aloes, etc., so as to permit the
easy drawing off of the useful fibres.
Having thus described the nature of my Invention and the best means known
to me to carry the same into practico, I claim,-
First. The process of treating textile plants which consists in exposing thom
soon after being cut to heat by enclosing them in a vessel into which steain, or hot
air, or gases are admitted, whereby the exterior cortical parts with the fibres
become easily separable from the central parts, and can be drawn off in the shape
of bands whereby the parallelism of the fibres is not destroyed, substantially as
specified and for the purposes set forth.
Second. The process of separating the fibres of plants from each other and
. from adjacent parts to which they adhere by means of a gum like resinous
matter, which consists in exposing them to a high temperature by enclosing them
in a vessel in which superheated steam, or hot air, or gases are admitted, and
afterwards drawing the fibres off from the material of the plant, substantially as
herein set forth and for the purposes specified.
In witness whereof, I, the said George Vian, have hereunto set my hand and
seal, this Thirteenth day of October, in the, year of our Lord One
thousand eight hundred and eighty.