Process for Cleansing or Purifying Woollen Fabrics.
Year: 1890

page_text: Date of Application, 26th Nov., 1890
Complete Specification Left, 4th Aug., 1891-Accepted, 3rd Oct., 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by the firm of PHILIPS AND MATHÉE, of The Wool
Washing and Carbonising Works, Rheinland, Germany.]
Process for Cleansing or Purifying Woollen Fabrics.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane,
in the County of London, Consulting Engineer and Patent Agent, do hereby
declare the nature of this invention to be as follows:-
During the spinning, weaving, and fulling processes there are accumulated in
woollen fabrics quantities of impurities which consist of fatty matters, combinations
of fatty acids with lime, magnesia, oxide of iron, or other similar bodies. The
removal of these is in itself a very difficult and tedious matter, but when such
fabrics, as is now generally the case, are carbonised with mineral acids in order to
destroy the vegetable impurities, it has not been possible hitherto to remove the
said impurities by means of the cleansing materials generally employed, such as
alkaline liquids, soaps, fullers earth &c., the impurities having become to a certain
extent insoluble. These impurities are mostly distributed very unequally over the
fabric and in consequence hereof the colors become fixed very unequally in the
subsequent dyeing process, producing stripes, spots and cloudiness in the finished
piece.
Furthermore, the color of the dye does not develop with clearness and purity
because the perfect union of the coloring matter with the fibres is prevented by
the coating of grease and other impurities which surround them.
From the foregoing it will be seen that a cheap and reliable process which allows
of the perfect removal of the before mentioned more or less insoluble impurities
from the woollen fabric directly after the carbonising is of the greatest importance
to the woollen manufacturer and dyer.
My correspondents have discovered that sulphurous acid sodium bisulphite and
all compounds which on the addition of acid, give off sulphurous acid, are admirably
adapted for this purpose.
The fabrics, after the carbonising process, are soaked in pure water together with
mineral acids and are then treated for some time with aqueous sulphurous acid or
with sodium bisulphite or with any other compound that gives off sulphurous acid
on the addition of acid.
The liquid, which contains the excess of sulphurous acid and a part of the impu-
rities, is then drawn off and the remainder of the sulphurous acid contained in the
fabric, together with the remainder of the impurities, are removed by means of soda
lye or any other alkaline liquid, after which the fabric is rinsed with water until
this runs off quite clear.
The sulphurous acid acts in the above process by destroying the combination of
the organic constituents of the impurities with the inorganic constituents such as
that of the fatty acids with the lime; the inorganic bodies pass into solution as
sulphites, the fatty acid and other organic matters such as resin &c. are readily
dissolved by the subsequent treatment with alkaline liquid.
Without the previous treatment with sulphurous acid, the solution of the
impurities in soda would be very imperfect.
It will be seen from the above that the invention comprises a new application of
sulphurous acid which has nothing in common with the known application thereof to
dveing purposes.

page_text: In order to-conclusively prove that by the new process far greater quantities of
impurities are removed from the woollen fabrics than in the old purifying process,
the following analytical results of the process may be given.
Two fabrics of the same kind as above were treated according to this invention
with sodium bisulphite and then with soda, using the same quantities of fluid as in
the first case.
.1.
1. 1
One litre each respectively of the soda solution of Experiment I and of the
bisulphite and soda solution of Experiment II were analysed:-
''I-1 litre soda solution (Experiment I) gave after evaporation and drying to
.... the constant weight: 20-43 grammes total residue consisting of "
16.73 gr.'soda, sodium sulphate, and mechanically separated wool fibres.
3.70 gr. dissolved impurities, (grease, resin, &c.).
. “
1.
...
m
II-A. 1 litre bisulphite solution (Experiment II) gave after evaporation
..and drying to the constant weight: 11.74 grammes total: residues,
consisting of
***
-3.71 gr. sodium bisulphite sodium sulphate and mechanically sepa-
rated wool fibres.
8.03
gr. dissolved impurities (lime, iron salts, organic compounds).
II B. 1 litre soda solution (Experiment II) gave after evaporation and
drying to the constant weight: 17.36 gr. total residues consisting of.
13:54 gr. soda, sodium sulphite mechanically separated wool fibres.
3:82 gr., dissolved impurities (organic substances, grease, resin &c.).
The sum of the impurities taken up by the bisulphite and soda solution' under the
new method, therefore amounts, in one litre to 8.03+3.82=11.85 gr., that is to say,
more than three times as much as was produced according to the old method
(=3.7 gr. per litre).
With the old method there was even used a somewhat stronger soda solution;
temperature and other conditions were the same in both experiments.
In 1 litre bisulphite solution (Experiment II A) were found 0-385 gr. inorganic
salts, precipitated by carbonate of ammonia (mainly lime and iron compounds); in
1 litre soda solution (Experiment I old process) only 0-096 gr. of such salts were
found.
Fabrics are obtained by my correspondents process which are free from all, to a
certain extent, insoluble impurities and which are particularly well suited for.
obtaining uniform and bright tints, with all coloring matters, and with very perfect
utilisation of the same.
Dated this 26th day of November 1890.
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Process for Cleansing or Purifying Woollen Fabrics.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane,
in the County of London, Consulting Engineer and Patent Agent, 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:-
During the spinning, weaving, and fulling processes there are accumulated in
woollen fabrics quantities of impurities which consist of fatty matters, combinations
of fatty acids with lime, magnesia, oxide of iron, or other similar bodies.
The removal of these is in itself a very difficult and tedious matter, but when such
fabrics, as is now generally the case, are carbonised with mineral acids in order to
destroy the vegetable impurities, it has not been possible hitherto to remove the
said impurities by means of the cleansing materials generally employed, such as
alkaline liquids, soaps fullers earth &c., the impurities having become to a certain
extent insoluble. These impurities are mostly distributed very unequally over the
fabric and in consequence hereof the colours become fixed very unequally in the
subsequent dyeing process, producing stripes, spots and cloudiness in the finished
piece.
Furthermore, the colour of the dye does not develop with clearness and purity
because the perfect union of the colouring matter with the fibres is prevented by
the coating of grease and other impurities which surround them.
which allows:
of the perfect removal of the before mentioned more or less insoluble impurities
from the woollen fabric directly after the carbonizing is of the greatest importance
to the woollen manufacturer and dyer.
From the foregoing it will be seen that a cheap and reliable process
My correspondents have discovered that sulphurous acid sodium bisulphite and
all compounds such as metal sulphites, bisulphites, and hydrosulphites which on the
addition of strong acids, give off sulphurous acid, are admirably adapted for this
purpose.
The fabrics, after the carbonising process, are soaked in pure water together with
mineral acids and are then treated for some time with aqueous sulphurous acid or
with solution of sodium bisulphite or of any other compound that gives off sulphurous
acid on the addition of acid.
In all these cases it is the sulphurous acid which is the effective agent; it can be
added in a free state as an aqueous solution or in a combined state as a salt, from
which the acid is set free by the addition of a stronger acid. For practical
purposes my correspondents prefer the use of sodium bisulphite as it contains one
molecule of sulphurous acid in a state where it is as active as in the free, state,
while on the other hand it is the cheapest and readiest means for treating any
matter with free sulphurous acid.
The sodium bisulphite is applied in such a manner and quantity that about four
to six pieces of cloth are soaked with five hundred litres of water in a machine
provided with rollers, and from one and a half to three litres. of sodium bisulphite
solution of a strength of 38° B. are added.
The cloth is then treated with this dilute solution for an hour or so. The strength
of the solution is varied according to the quality and weight of the cloth under
treatment. The sodium bisulphite can be replaced by a solution of free sulphurous
acid or a solution of any sulphite, but the application of sodium bisulphite will, in
practice, be found most convenient.
The liquid, which contains the excess of sulphurous acid and a part of the impu-
rities, is then drawn off and the remainder of the sulphurous acid contained in the.
fabric, together with the remainder of the impurities are removed by means of soda.
lye or any other alkaline liquid, after which the fabric is rinsed with, water until
the water runs off quite clear.
t

page_text: The sulphurous acid acts in the above process by destroying the combination of
the organic constituents of the impurities with the inorganic constituents such as
that of the fatty acids with the lime; the inorganic bodies are converted into
sulphites and pass into solution, the fatty acid and other organic matters such as
resin &c., are readily dissolved by the subsequent treatment with alkaline liquid.
Without the previous treatment with sulphurous acid, the solution of the impu-
rities in soda or other alkali would be very imperfect.
It will be seen from the above that the invention comprises a new application of
sulphurous acid which has nothing in common with the known application thereof
to dyeing purposes.
In order to conclusively prove that by the new process far greater quantities of
impurities are removed from the woollen fabrics than in the old purifying process,
the following analytical results of the process may be given.
fabrics of the same kind as above were treated according to this invention
dium bisulphite and then with soda, using the same quantities of fluid as in
case.
litre each respectively of the soda solution of Experiment I and of the
ite and soda solution of Experiment II were analysed:
1 litre soda solution (Experiment I) gave after evaporation and drying to
the constant weight: 20-43 grammes total residue consisting of :—
16.73 gr. soda, sodium sulphate, and mechanically separated wool fibres.
3.70 gr. dissolved impurities (grease resin, &c.).
A. 1 litre bisulphite solution (Experiment II) gave after evaporation
and drying to the constant weight: 11.74 grammes total residues,
consisting of
3.71 gr. sodium bisulphite sodium sulphate and mechanically separated
wool fibres.
8.03 gr. dissolved impurities (lime, iron salts, organic compounds).
B. 1 litre soda solution (Experiment II) gave after evaporation and
drying to the constant weight: 17-36 gr. total residues consisting of
13.54 gr. soda, sodium sulphite mechanically separated wool fibres.
3.82 gr. dissolved impurities (organic substances, grease, resin &c.).
sum of the impurities taken up by the bisulphite and soda solution under the
thod, therefore amounts, in one litre to 8.03 + 3-82-11-85 gr. that is to say,
han three times as much as was produced according to the old method
gr. per litre).
the old method there was even used a somewhat stronger soda solution;
ature and other conditions were the same in both experiments.
litre bisulphite solution (Experiment II A) were found 0-385 gr. inorganic
recipitated by carbonate of ammonia (mainly lime and iron compounds); in
soda solution (Experiment 1 old process) only 0.096 gr. of such salts were
ics are obtained by my correspondents process which are free from all, more
insoluble impurities and which are particularly well suited for obtaining

page_text: uniform and bright tints with all colouring matters, and with very perfect utilisation
of these matters.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim is :-
The herein described process for cleansing or purifying woollen fabrics by the
application of sulphurous acid, sodium bisulphite or other compounds which on
addition of acid give off sulphurous acid, whereby fats, lime soaps and other
impurities in the wool are brought into a condition to be dissolved and removed by
alkaline liquids.
Dated this 4th dox of Ava 1901
ABEL & IMRAY,
Agents for the Applicant.