An Improved Process of and Apparatus for Dyeing Cotton-yarn.
Year: 1888

page_text: Date of Application, 22nd Dec., 1888
Complete Specification Left, 3rd Sept., 1889-Accepted, 12th Oct., 1889
PROVISIONAL SPECIFICATION.
An Improved Process of and Apparatus for Dyeing Cotton-yarn.
I, HERMANN RECKER, of 20 Markt, Zittau, Saxony, in the Empire of Germany,
Manufacturer, do hereby declare the nature of this invention to be as follows :-
This invention relates to a process of dyeing cotton-yarn warps with aniline-black,
and to apparatus for carrying the said process into effect.
Heretofore it has not been possible to dye cotton-yarn warp with fast aniline-black
and dress the same in one operation so as to beam the warp ready for use in the loom.
In the passage of the yarn through the dye-vats, the dyes cannot be maintained at the
same strength, especially if the vats are heated with steam. The passage of the yarn
through dye, steam and dressing baths is effected very quickly; all the solutions
must, therefore, be very concentrated; if the solution of the dye becomes weaker, the
fixing will take longer, and, if the vapours or the baths which serve for the fixing
become weaker, the solution of the dye, in order to compensate for this, will have to
be more concentrated still. To obtain uniformity under these circumstances is scarcely
possible even if considerable care be taken.
To produce a fast dye of aniline black in this manner is not possible with the vats
heretofore used by dyers, even if the dyes in the vats are kept ever so concentrated.
The oxidation of the aniline takes place in a very short time mostly outside the yarn
in the entire vat, and in order to take up this oxidized product the yarn requires very
much time. The dye-bath in which a chemical process takes place cannot he kept
at the same strength by adding to the same. Now, according to the said invention,
the yarn is first saturated with chloride of aniline and then the oxidation is gradually
effected. In order to hasten the latter in a proper manner, the yarn, which has been
impregnated with chloride of aniline and previously freed from an excess of liquid by
squeezing, is passed through a somewhat concentrated solution of potassium chromato,
but only for a very short time, so that the yarn only takes up the liquid without
allowing any time for a chemical process to take place in this liquid. This yarn,
which has been saturated with chloride of aniline and squeezed, now passos, after
having been thoroughly wetted by the solution of chrome, a very long distance through
a tower in order to bring it into contact with hot air in motion and thus allow it to
oxidize.
The apparatus employed for carrying the said process into effect comprises a frame
for receiving the warp-beams, a boiler, two dye-baths, an oxidizing tower and a washing,
dressing and drying device.
The process is carried out with the use of this apparatus in the following
manner :-
From the warp-beams the threads pass over suitably arranged rollers to the said
boiler or tank, which is heated by means of a steam-pipe. From the boiler or tank
the threads pass to the first dye-bath, which contains chloride of aniline. The guide
rollers in this dye-bath are so arranged that the threads are several times steeped in
the liquid, so that the latter completely penetrates the threads. In order however
that the threads shall not unnecessarily take up too much chloride of aniline and carry
away with them, they are caused to pass in a well-known manner between squeezing
rollers.
it
From the first dye-bath, the threads are conducted to the second dye-bath which
consists of potassium chromate. The guide-rollers in the said bath are so arranged
that the threads are immersed in the liquid only for a short time. By this means, the
oxidation is obviated during the immersion, and will be effected in the above-
mentioned tower. In the interior of this tower, which is preferably made of the shape
of an inverted U, are supported a number of horizontal rollers which are parallel

page_text: with each other. Pipes are used for heating the air which is caused to enter the
tower from below, and which, after, having passed in contact with the aforesaid rollers,
leaves the tower above through a discharge pipe or passage:
The potassium chromate alone-will effect: the oxidation of the chloride of..aniline,
this oxidation is, however, so, much,hastened by the oxygen of the air which passes
continuously through the tower that, in about 45 seconds, a deep black colour appears
on the yarn which is conducted in zig-zag lines over the said rollers.
For the purpose of enabling this operation to be accurately observed, the side walls
of the tower are partially made of transparent material.
The yarn leaving the oxidizing tower is washed, dressed, dried and beamed in a
well-known manner.
In-order that the threads shall not become entangled in the oxidizing tower, the
.aforesaid rollers are provided with staples or the like.
Accordingly the warp is not liable to be either dyed or beamed in a defective manner
in the process herein before, described, for, as the solutions which effect the dyeing are
contained in separate receptacles, it is very easy to maintain them at an equal strength.
If they are, diluted too much, the oxidation: will be effected later, and, if they are
diluted too, little,, it will take place earlier than in the regular operation. Any
defective action of the dye-baths is at once detected if the observation takes place
with a little care, and chloride. of aniline, potassium chromate or water can be added
to the dye-vats according to requirements. It is advisable to arrange the apparatus in
such.a, manner that, the dyeing, of the yarn is finished just as the latter passes upon the
uppermost rollers.; if in this case the dyeing should take place on one or the other
side, this. can be conveniently. observed and the necessary. remedies can be applied
at once..
By the use of two dye-baths.and of, such, an arrangement that the yarn saturated
with chloride of aniline is, steeped, in the second dye-bath only for a time, a chemical
process is obviated, within, the dye-baths..
A further advantage; of this process consists in the fact that all the chemicals can be
used, to the last drop, this is therefore the cheapest and quickest of the processes hitherto
used. of obtaining a fast aniline-black.
By guiding the yarn-warp, the threads on leaving the first bath will not as formerly
be curled together.. When curled. together, the threads on passing through the
second, bath will take up, liquid irregularly so that finally the several threads often
cannot be separated. This curling, of the yarns being obviated, the wet yarn, from
the moment when it enters the, said boiler or, tank till it leaves the soap and soda bath,
bears firmly upon the roliers and guides, and is so conducted that no great length of
the yarn is at, any time, free, and. the: free, part of the yarn is never steeped in the
. liquid..
1 1
1000
HASELTINE, LAKE & Co.,.
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE. SPECIFICATION...
An Improved Process of and Apparatus for Dyeing Cotton Yarn.
I, HERMANN RECKER, of 20 Markt, Zittau, Saxony, in the Empire of Germany,
Manufacturer,,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.:-
This invention relates to a process of, dyeing cotton yarn warps. aniline-black, and
to apparatus for carrying the said. process;into; effect..
Heretofore it has, not been possible to, dye,cotton-yarn warp with fast aniline-black
and dress the same in one; operation so.as. to beam tlie, warp ready for use in the loom.
In the passage of the yarn through the dye vats, the dyes cannot be maintained at
the same strength, especially if the vats heated with steam: The passage of the yarn

page_text: through dye, steam and dressing baths is effected very quickly, all the solutions must
therefore be very concentrated, if the solution of the dye becomes weaker the fixing
will take longer, and if the vapours or the baths which serve for the fixing become
weaker the solution of the dye in order to compensate for this, will have to be more
concentrated still. To obtain uniformity under these circumstances is scarcely possible
even if considerable care be taken.
To produce a fast dye of aniline black in this manner is not possible with the vats
heretofore used by dyers, even if the dyes in the vats are kept ever so concentrated.
The oxidation of the aniline takes place in a very short time mostly outside the yarn'
in the entire vat, and in order to take up this oxidized product the yarn requires
very much time. The dye-bath in which a chemical process takes place cannot be
kept at the same strength by adding to the same. Now according to the said
invention the yarn is first saturated with chloride of aniline and then the oxidation is
gradually effected. In order to hasten the latter in a proper manner, the yarn which
has been impregnated with chloride of aniline, and previously freed from an excess of
liquid by squeezing, is passed through a somewhat concentrated.solution of potassium
chromate, but only for a very short time, so that the yarn only takes up the liquid
without allowing any time for a chemical process to take place in this liquid. This
yarn, which has been saturated with chloride of aniline and squeezed, now passes,
after having been thoroughly wetted by the solution of chrome, upon a very long way
through a tower in order to bring it into contact with hot air in motion and thus
allow it to oxidize.
The apparatus employed for carrying the said process into practice is represented
in the accompanying drawing in longitudinal section.
This apparatus comprises a frame for receiving the warp-beams a a boiler b
two dye baths c and d, an oxidizing tower e and a washing, dressing and drying
device.
The process is carried out with the use of this apparatus in the following
manner:
From the warp-beams a the threads pass over suitably arranged rollers to the said
boiler or tank which is heated by means of a steam-pipe. From the boiler or tank
the threads pass to the first dye-bath c which contains chloride of aniline. The
guide rollers in this dye bath are so arranged that the threads are several times
steeped in the liquid so that the latter completely penetrates the threads. In order
that however the thread shall not unnecessarily take up too much chloride of aniline
and carry it away with them, they are caused to pass in the known manner between
squeezing rollers.
From the first dye-bath c the threads are conducted to the second dye-bath d
which consists of potassium chromate. The guide rollers in the said bath are so
arranged that the threads are immersed in the liquid only for a short time. By this
means the oxidation is obviated during the immersion and will be effected in the
above-mentioned tower e. In the interior of this tower, which is preferably made of
inverted Ushape are supported a number of horizontal rollers which are parallel
with each other. Heating pipes h are used for heating the air which is caused to
enter the tower from below, and which, after having passed in contact with the aforesaid
rollers, leaves the tower above through a discharge pipe or passage k.
The potassium chromate alone will effect the oxidation of the chloride of aniline,
this oxidation is however so much hastened by the oxygen of the air which passes
continuously through-the tower that in about 45 seconds a deep black colour appears
on the yarn which is conducted in zig-zag lines over the said rollers f.
For the purpose of enabling this operation to be accurately observed the side walls
of the tower are partially made of transparent material.
The yarn leaving the oxidizing-tower is washed, dressed, dried and beained in the
known manner.
In order that the threads shall not become entangled in the oxidizing tower, the
aforesaid rollers are provided with staples 7 or the like,

page_text: Accordingly the warp is not liable to be either dyed or beamed in a defective
manner in the process hereinbefore described, for as the solutions which effect the
dyeing are contained in separate receptacles it is very easy to maintain them at an
equal strength. If they are diluted too much the oxidation will be effected later, and
if they are diluted too little it will take place earlier than in the regular operation.
Any defective action of the dye-baths is at once detected if the observation takes place
with a little care, and chloride of aniline, potassium chromate, or water can be added
to the dye-vats according to requirements. It is advisable to arrange the apparatus
in such a manner that the dyeing of the yarn is finished just as the latter passes upon
the uppermost rollers; if in this case the dyeing should take place on one or the other
side, this can be conveniently observed and the necessary remedies can be applied
at once.
By the use of two dye-baths and of such an arrangement that the yarn saturated
with chloride of aniline is steeped in the second dye-bath only for a time, a chemical
process is obviated within the dye-baths.
A further advantage of this process consists in the fact that all the chemicals can be
used to the last drop; this is therefore the cheapest and quickest of the processes
hitherto used for obtaining a fast aniline-black.
By guiding the yarn warp the threads on leaving the first bath will not as formerly
be curled together. When curled together the threads on passing through the second
bath will take up liquid irregularly so that finally the several threads often cannot be
separated. This curling of the yarns being obviated, the wet yarn, from the moment.
when it enters the said boiler or tank till it leaves the soap and soda bath, bears
firmly upon the rollers and guides, and is so conducted that no great length of
the yarn is at any time free and the free part of the yarn is never steeped in the
liquid.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
First. A process of dyeing cotton yarn warps with aniline black characterized by
conducting the warps into a solution of chloride of aniline, then quickly through
a solution of potassium chromate and over a series of rollers against which air is caused
to pass, so that the oxidation occurs outside the dye baths.
Second. For carrying out the process above described the arrangement of an
oxidizing tower e behind the dye baths c and d over the rollers of which the
yarn is conducted in zig-zag lines and comes in contact with air which is continuously
admitted.
September 03.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.