A Process for the Decortication, Scouring or like Treatment of Ramie, Flax, Hemp, Jute, Alfa, and Phormium, and other Fibres.
Year: 1899

page_text: A Process for the Decortication, Scouring or like Treatment of Ramie,
Flax, Hemp, Jute, Alfa, and Phormium, and other Fibres.
I, CHARLES ALBERT RIGAULT, of 195, Rue de Vangirard, Paris, in the Republic
of France, Pharmacist, do hereby declare the nature of this invention to be as
follows;
-
Numerous attempts have been made to decorticate and scour ramie by chemical
means all of which seem to have for their chief object the separation in one or in
several operations at one and the same time of both the bark and the internal
core which supports the cluster of fibres and depriving them of the gum by
which they are held together.
In analysing I have been led to the conclusion that the reactions necessary for
the extraction of the wood and certain portions of the bark must act in a pre-
judicial manner upon the fibres to the detriment of their solidity and brilliancy.
The scouring more commonly called ungumming of the ramie-fibres is carried
out by any known process which gives satisfactory results providing however
that the core has previously been decorticated or at least disaggregated either by
steaming, stripping or otherwise.
My process which is a kind of scouring or ungumming presents the feature
that it may equally well be applied to plants protected by bark as to those having
so to speak no bark.
It was found necessary in order to succeed to render the wood or the bark
sufficiently porous to enable the bath to penetrate into the cluster of fibres by
attacking the same simultaneously both from the exterior and from the interior.
The most important constituent parts of ramie stalks are pectine together with
cutose and vasculose which are found in the wood in the bark and in the gum
thereof and I have conceived the idea of treating them with gallic-acid com-
bined with alkalies. It is this combination of the action of tannin with that of
the alkalies in the scouring bath which constitutes the essential and distinctive
character of my invention.
The multiple combinations which may be produced by means of these two
classes of materials, act only very slowly and at high temperatures upon the
textile fibres so that the proportioning of our baths is superfluous so to speak:
the minimum of these materials necessary for the operation is determined by
the quantity of pectine, salts of iron and other substances such as albumen,
cutose and vasculose contained in the ramie under treatment, such substances
being contained in the ramie in varying quantities according to its nature and
to the country where grown. The above statements are equally applicable to
all other textiles.
I prefer more especially the following combination:

page_text: In 100 litres of water (of any obtainable quality) I dissolve soda, or caustic
potash until the bath attains the density of 50 Beaume I then add 150 grammes
of digallic acid (tannin) treated with ether or with alcohol or even 300 grammes
of pulverized gall-nut.
I then heat the bath to a temperature of 100° C. and maintain this temperature
throughout the operation.
The ramie stalks or the like, are then immersed in bundles, as made up after
they have been cut and stripped of their leaves either by hand or mechanically,
in the bath thus prepared and left there for about 25 minutes.
When coming from the bath the stalks are completely disaggregated, the
wood has lost its primitive stiffness by the extraction process, and the bark owing
to the same reason appears in a soft condition and can almost completely be
removed by energetic washing.
My experience in this matter enables me to explain with an amount of cer-
tainty the chemical reactions which take place in my process.
First of all the action of air seems to be necessary for producing the action
of the tannic bath upon the ramie and this action is evidently due to the
oxidation produced (through the intervention of the products of decomposition
of tannin in the midst of alkalies and in contact with air.
These products from the decomposition of tannin. act as an oxidizing mediumi,
that is to say they become oxidized at the expense of the air and in turn oxidize
the cutose, vasculose and pectose which become split up under the action of
alkali.
The cutose into stearo-acids and oleo-cutic soluble in alkalies.
The vasculose, by forming resinous acids less hydrated and more oxidated
than the vasculose, soluble in alkalies.
The pectose, in becoming transformed into metapectates soluble in organic
salts and alkalies, i.e. in tannoxylates and tannomelanates of soda resulting
from the decomposition of tannin
After having oxidized part of the agglutinated substances of the ramie the
tannin oxidizer becomes again oxidized by contact with the air and thus regains
its oxidizing properties in regard to the cutose, vasculose and pectose. The
phenomenas of oxidizing and reducing continue during the operation, the tannin
oxidising medium acting as a conveyor of the oxygen, which explains how such
a small dose of tannin as that here used for the treatment of the ramie can
produce such an efficaceous action.
The gathering of the fibres freed from the bark and gum by which they
were surrounded may be effected in two ways.
It may be taken out by hand, and this is most convenient in the countries
where ramie is cultivated where labour is cheap.
Or it may be done mechanically by subjecting the ramie to the action of
rollers. The machinery employed for this is well known and requires no
description, besides it forms no part of the invention.
In completing the description of my process I will here state that analogous
results have been obtained by regulating the density of the bath to degrees vary-
ing between 3 to 20° Beaume of soda, or potash, and doubling the dose of
digallic acid or gall-nut. The raising of the temperature has not sensibly
modified the results, which seems to indicate that the substances to be extracted
only absorb so much of the materials to the action of which they are subjected,
as is necessary for the reactions thereby produced, and that all the remaining
parts, amongst which are also the fibres, are not subjected to their influence.
Furthermore I treat the materials indifferently whether they are green
plants, semi-dry or dried even for several years.
I can also employ, in form of carbonates, other solutions of alkaline earths
such as baryta, strontian and especially lime and always in combination with
gallic acids.
By the use of potash the fibres receive à silky appearance while soda yields

page_text: products which may be compared to flax but more glittering which the action of
the rollers renders glossy beyond anything like flax.
Lime yields products of a drier nature similar to hemp and jute but having
greater and distinct brilliancy.
Dated this 07th
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
A Process for the Decortication, Scouring or like Treatment of Ramie,
Flax, Hemp, Jute, Alfa, and Phormium, and other Fibres.
1, CHARLES ALBERT RIGAULT, of 195, Rue de Vaugirard, Paris, in the Republic
of France, Pharmacist, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
Numerous attempts have hitherto been made to decorticate and scour ramie
by chemical means, all of which seem to have for their chief objects the separa-
tion, in one or in several operations at one and the same time, of both the bark
and the stalk which supports the cluster of fibres, and to deprive them of the
gum by which they are held together.
In my analysing I have been led to the conclusion that the reactions necessary
for the extraction of the wood and certain portions of the bark must act in a
prejudicial manner upon the fibres, to the detriment of their solidity and
brilliancy.
The scouring, more commonly called ungumming, of the ramie-fibres is
carried out by any known process which gives satisfactory results, providing
however that the core has previously been decorticated, or at least disaggregated
either by steaming, stripping or otherwise.
My process, which is a kind of scouring or ungumming, presents the feature
that it may equally well be applied to plants protected by bark, as to those
having, so to speak, no bark.
It was found necessary in order to succeed, to render the wood and the bark
sufficiently porous to enable the bath to penetrate into the cluster of fibres by
reaching the same simultaneously both from the exterior and from the interior.
The most important constitutent parts of ramie stalks are pectine, together
with cutose and vasculose which are found in the wood in the bark and in
the gum thereof, and according to my invention I treat them with digallic-acid
combined with alkalies. It is this combination of the action of tannin with that
of the alkalies in the scouring bath which constitutes the essential and dis-
tinctive character of my invention.
The multiple combinations which may be produced by means of these two
classes of materials, act only very slowly and at high temperatures upon the
textile fibres, so that the proportioning of the baths is superfluous so to speak;
the minimum of these materials necessary for the operation is determined by
the quantity of pectine, salts of iron and other substances, such as albumen,
cutose and vasculose contained in the ramie under treatment, such substance
being contained in the ramie in varying quantities according to its nature and
to the country where grown. The above statements are equally applicable to
all other textiles.

page_text: I prefer more especially the following combination :
Soda, or caustic potash is dissolved in 100 litres of water until the bath attains
the density of 5° Beaume, 150 grammes of digallic acid (tannin) produced by
means of ether or alcohol, or otherwise, are then added; or even 300 grammes of
pulverized gall-nut.
I then heat the bath to a temperature of 100° C. and maintain this tem-
perature throughout the operation.
The ramie stalks or the textile plants, are immersed in bundles, as made up
after they have been cut and stripped of their leaves either by hand or mechani-
cally, in the bath thus prepared and left there for about 25 minutes.
When coming from the bath the stalks are completely disaggregated, the
wood has lost its primitive stiffness by the extraction process and the bark
owing to the same reason appears in a soft condition and can almost completely
be removed by energetic washing.
My experience in this matter enables me to explain with an amount of cer-
tainty the chemical reactions which take place in my process.
First of all the action of air seems to be necessary for producing the action of
the tannic bath upon the ramie and this action is evidently due to the oxidation
produced through the intervention of the products of decomposition of tannin
in the midst of alkalies and in contact with air.
These products from the decomposition of tannin act as an oxidising medium,
that is to say they become oxidized at the expense of the air, and in turn oxidize
the cutose, vasculose and pectose which transform them under the action of
alkali; the cutose into stearo-acids and oleo-cutic acid soluble in alkalies; the
vasculose, by forming resinous acids less hydrated and more oxidated than the
vasculose, soluble in alkalies; the pectose, in becoming transformed into meta-
pectates soluble in organic salts and alkalies, i.e. in tannoxylates and tannome-
lanates of soda resulting from the decomposition of tannin.
After having oxidized part of the agglutinated substances of the ramie the
tannin oxidizer becomes again oxidized by contact with the air and thus regains
its oxidizing properties in regard to the cutose, vasculose and pectose. The
phenomena of oxidizing and reducing continue during the operation, the tannin
oxidising medium acting as a conveyor of the oxygen, which explains how such
a small quantity of tannin as that here used for the treatment of the ramie, can
produce such an efficaceous action.
The gathering of the fibres freed from the bark and gum by which they were
surrounded may be effected in two ways.
It may be taken out by hand, and this is most convenient in the countries
where ramie is cultivated and where labour is cheap.
Or it may be done mechanically by subjecting the ramie to the action of
rollers. The machinery employed for this is well known and requires no
description, as it forms no part of my invention.
In completing the description of my process I will here state that analogous
results have been obtained by regulating the density of the bath to degrees
varying between 34° to 20° Beaume of soda, or potash, and doubling the quantity
of digallic acid or gall-nut. The raising of the temperature has not sensibly
modified the results, which seems to indicate that the substances to be extracted
only absorb so much of the materials to the action of which they are subjected,
as is necessary for the reactions thereby produced, and that all the remaining
parts, amongst which are also the fibres, are not subjected to their influence.
Furthermore I treat the textile plants indifferently whether they are unripe,
semi-dry, or even dried for several years.
I can also employ every kind of carbonates, or other solutions of alkaline
earths such as baryta, strontia and especially lime, and always in combination
with di-gallic acid.
By the use of potash the fibres receive a silky appearance, while soda yields
products which may be compared to flax; but more glittering.

page_text: Lime yields products of a drier nature similar to hemp and jute but having a
distinct brilliancy.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:
-
1. A process of chemical decortication and scouring of ramie and other textile
plants, flax, hemp, jute, alfa, and the like, consisting in adding tannin to the
alkalies for effecting simultaneously the decortication and the scouring of the
ramie and other textile plants, and by preference with the aid of heat, thus
obtaining a novel technical effect resulting from the simultaneous action of
the oxygen of the air, of the alkali and the products of decomposition of tannin
which act as an oxidizing medium and which cause the oxidation of the cutose
and of the agglutinated substances of the fibres and their splitting up into com-
pounds soluble in alkaline salts and in alkaline lye substantially as described.
2. The scouring bath prepared as herein before described, with an alkaline
solution of soda, or potash, or a lime water to which is added tannin, preferably
digallic-acid in suitable proportions, said acid serving at one and the same time
to facilitate the scouring of the fibres and to extract the elements which con-
stitute the gum such as the cutose, vasculose pectose while simultaneously
therewith the alkali effects the disaggreation of the bark and of ligneous particles
substantially as described.
Dated this 21st day of February 1900.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.