AN IMPROVED PROCESS OF SOFTENING, CLEANSING, AND DECOLORIZING FIBRES AND FABRICS
Year: 1876

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
"
County of Middlesex, Patent Agent, for the Invention of AN IMPROVED
PROCESS OF SOFTENING, CLEANSING, AND DECOLORIZING FIBRES AND FABRICS."
A communication from abroad by William Maynard, of New York City, United
States of America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 28th November 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middle-
sex, Patent Agent. "AN IMPROVED PROCESS OF SOFTENING, CLEANSING, AND
DECOLORIZING FIBRES AND FABRICS."
This Invention relates to the use of detergents previous to bleaching, by which
cotton, silk, wood, and grasses, such as hemp and flax, may be softened, decolorized,
and cleansed without boiling.
The process consists in the use of sulphurous acid hydrated (i.e., dissolved in
water) in connection with various proportions of an alkali, but principally sal soda.
In referring to the processes having a resemblance to that herein-after described
I would state that it is not new to deterge or cleanse the fibre by first steeping it in
a weak acid and afterwards in an alkaline solution preparatory to bleaching the same
by chlorine, and that it is also old in bleaching operations to employ the hyposulphite
of soda or other alkali, together with with a subsequent treatment by an acid to
decompose the salt and liberate the sulphurous acid in the fibres of the cloth to be
bleached. I therefore lay no broad claim to these reagents, nor to the process
referred to.
The Invention consists, for softening, deterging, and decolorizing the fibre, in
using the hydrated sulphurous acid mixed and neutralized with a solution of an
alkali in its crude state, instead of using the crystallized sulphite salt, whereby I
avail myself of certain qualities of the said newly formed or incipient neutral com-
pound of sulphurous acid and the alkali, which do not belong to a solution of the
crystallized sulphite salt, and which I find to be the only method of thoroughly
cleansing, deoxidizing, and decolorizing the fibre without boiling.
In carrying out the Invention, the sulphurous acid being prepared by means of
.

page_text: the apparatus forming the subject of Letters Patent granted to myself, is a com-
munication from the said William Maynard, dated August 2nd, 1876, No. 3094, is
placed in a receptacle large enough for the purposes required, and means provided
for stirring it. The potash or other alkali is then poured in gently and carefully (in
strong solution) until the moment that the sulphurous acid ceased to be evolved. The
goods are then placed in the liquor, and the temperature raised to 100° or 150° F.,
and allowed to remain there for 'from 3 to 6 hours, when they may be washed in
pure water. The theory of the action is that the reducing agent deprives the
organized material of its oxygen; the organic matter being thus decomposed nascent
hydrogen seeks an affinity with the nitrogen of the organic matter, and doubtless
amidogen (N H.), or indogen N H is formed, which uniting with one atom of the
base, say, for example, potassium forms potassamine, and thus the organized
material is deterged from its organic matter without any destruction of its vital
constituents.
The principal feature of this discovery is not the use of sulphurous acid hydrated,
or the use of an alkali, or the combination of an oxy acid with a basic acid
denominated by the termination of "ite" or "ate," but the use of sulphurous acid
(hydrated by means of the apparatus before referred to) combined with a solution
of potash or other alkali in incipient combination as described.
In neutralizing the sulphurous acid I employ magnesia for silk, sal soda for cotton,
and potash or soda for hemp, jute, and flax, as these reagents are best adapted to
the spcial requirements of the several fibres...
I am aware of the fact that claims have been set forth and secured by Letters
Patent for decolorizing vegetable fibres by the use of weak acids, followed by
treatment with alkalies, but these were not described nor neutralized so as to make
them perform the object of this Invention, or to enable persons unacquainted with
the process to use them. This process of deterging and decolorizing is effected
without the mechanical effect of boiling, thereby saving the expense of steam, and
in less than one-fourth part of the time now employed, and with less than half the
labor.
The neutralization of the sulphurous acid by the alkali, it will be seen, is also
effected, not by combining them in crystalline compounds of hyposulphite of soda,
but by combining the crude alkali with the liquid hydroted acid cheaply manu-
factured by the apparatus before referred to, thus saving the expense of crystallization
which is ordinarily effected by boiling the alkali with sulphur and evaporating.
This neutralization of the two reagents also not only prevents the injurious caustic
action of the stronger or weak alkalies, but it effects the cleansing and decolorizing
of the fibre under the most favourable condition, for the compound which is formed
by the sulphurous acid and alkali is in a peculiar condition, which is rather that of
a mechanical mixture than a defined sulphite salt, in which the presence of the
alkali with the sulphurous acid causes the latter to exercise a more active chemical
affinity for the oxygen of the coloring matter in the fibre, and thus more completely
cleanses and decolorizes the same.
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
5th April 1877.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "AN IMPROVED PROCESS OF SOFTENING, CLEANSING, AND DECO-
LORIZING FIBRES AND FABRICS." A communication from abroad by William
Maynard, of New York City, United States of America.
This Invention relates to the use of detergents previous to bleaching, by which
cotton, silk, wood, and grasses, such as hemp, flax, &c., may be softened, decolorized,
and cleansed without boiling either in the raw state or woven into fabric,

page_text: The process consists in the use of sulphurous acid hydrated (i.e., dissolved in
water) in connection with various proportions.of an alkali, but principally sal soda.
In referring to the processes having a resemblance to the present Invention I
would state that it is not new to deterge or cleanse the fibre by first steeping it in a
weak acid, and afterwards in an alkaline solution preparatory to bleaching the same
by chlorine, and that it is also old in bleaching operations to employ the hyposulphite
of soda or other alkali, together with a subsequent treatment by an acid to decom-.
pose the salt and liberate the sulphurous acid in the fibres of the cloth to be
bleached. I therefore lay no broad claim to these, reagents, nor to the process
referred to.
The Invention consists, for softening, deterging, and decolorizing the fibre, in
using the hydrated sulphurous acid mixed and neutralized with a solution of an
alkali in its crude state, instead of using the crystallized sulphite salt, and thereby
utilizing certain qualities of the said newly formed or incipient neutral compound
of sulphurous acid and the alkali, discovered empirically by the Inventor of the
herein-described process, which do not belong to a solution of the crystallized
sulphite salt, and an application of which discovery is found to be the only method
of thoroughly cleansing, deoxidising, and decolorizing the fibre without boiling.
In carrying out the Invention, the sulphurous acid being prepared by means of
the apparatus forming the subject of Letters Patent granted to me, and bearing date
August 2nd, 1876, No. 3094, is placed in a receptacle large enough for the purposes
required, and means provided for stirring it. The potash or other alkali is then
poured in gently and carefully (in strong solution) until the moment that sulphurous
acid ceases to be evolved. The goods are then placed in the liquor, and the tempe-
rature raised to 100° or 150° Fah., and allowed to remain there for from 3 to 6
hours, when they may be washed in pure water. The theory of the action is that
the reducing agent deprives the organized material of its oxygen; the organic
matter being thus decomposed nascent hydrogen seeks an affinity with the nitrogen
of the organic matter, and doubtless amidogen (NH2) or imdogen (NH) is formed,
which, uniting with one atom of the base, say, for example, potassium, forms potas-
samine, and thus the organized material is deterged from its organic matter without
any destruction of its vital constituents.
"
The principal feature of this discovery is, not the use of sulphurous acid hydrated,
or the use of an alkali, or the combination of an oxy acid with a basic acid, deno-
minated by the termination of "ite" or ate," but the use of sulphurous acid
(hydrated by means of the apparatus before referred to) combined with a solution of
potash or other alkali in incipient combination, as described.
In neutralizing the sulphurous acid I employ magnesia for silk, sal soda for
cotton, and potash or soda for hemp, jute, and flax, as these reagents are best adapted
to the special requirements of the several fibres.
I am aware of the fact that claims have been set forth and secured by Letters
Patent for decolorizing vegetable fibres by the use of weak acids followed by treat-
ment with alkalies, but these were not described nor neutralized so as to make them
perform the object of this Invention, or to enable persons unacquainted with the
process to use them. This process of deterging and decolorizing is effected without
the mechanical effect of boiling, thereby saving the expense of steam, and in less
than one-fourth part of the time now employed, and with less than half the labor.
The neutralization of the sulphurous acid by the alkali, it will be seen, is also
effected, not by combining them in crystalline compounds of hyposulphite of soda,
but by combining the crude alkali with the liquid bydrated acid cheaply manu-
factured by the above-mentioned apparatus, thus saving the expense of crystallization,
which is ordinarily effected by boiling the alkali with sulphur and evaporating.
This neutralization of the two reagents also, according to the present process, not
only prevents the injurious caustic action of the stronger or weak alkalies, but it
effects the cleansing and decolorizing of the fibre under the most favorable condition,
for the compound which is formed by the sulphurous acid and alkali is in a peculiar
condition, which is rather that of a mechanical mixture than a defined sulphite salt

page_text: in which the presence of the alkali with the sulphurous acid causes thelatter to
exercise a more active chemical affinity for the oxygen of the coloring matter in the
fibre, and thus more completely cleanses and decolorizes the same.
Having described the nature of the said 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 herein-described process of cleansing,
softening, and decolorizing vegetable and animal fibre, either in the raw state or
woven into fabric, by subjecting them to the action of hydrated sulphurous acid
mixed with an alkali in incipient combination, substantially as and for the purpose
set forth.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Fifth day of April, in the year of our Lord One
thousand eight hundred and seventy-seven.
A. M. CLARK. (L.S.)