IMPROVEMENTS IN DYEING FABRICS, ANILINE-BLACK, AND IN APPARATUS THEREFOR
Year: 1884

page_text: I CARL REINHARD PREIBISCH, doctor of philosophy, manufacturer of the firm.
of C. A Preibisch of Reichenau near Littau, Saxony German Empire do hereby
declare the nature of the said invention for "IMPROVEMENTS IN DYEING FABRICS,
ANILINE-BLACK, AND IN APPARATUS THEREFOR to be as follows:-
دو
For dyeing black by means of aniline three different methods have been heretofore
practised. In the oldest, principally used for prints the development of the black
colour is effected in so called oxidation-chambers, viz:-in chambers in which the
fabric printed with the printing dye is hung up after having passed through a
drying box in which said dye rapidly dries; the oxidation then proceeds by certain
rules determined according to the degree of dampness or dryness.
This process in which the goods are; hung up is only suited for developing
patterns can however not be employed when the cotton fabric is to be dyed black
in the ground as in that case where the fabric is hung up streaks of lighter colour
remain wherever the fabric has not been evenly stretched and exposed to the air
and these streaks cannot be removed by subsequent manipulation.
A second process has therefore soon been adopted in those cases where a black
ground colour is required; according to this the black colour is developed in a
steam box and the fabric;. having passed through the preliminary treatment, is
oxidised simply by steaming and without being dried. The aniline black produced
by steaming is however much inferior with regard to its beauty and purity to that
produced by oxidation by means of air. The third method now almost universally
used for dyeing cotton yarns in the hank as well as in chains, is based on the
employment of a metallic salt, usually chromate of potassa, for effecting the
oxidation in the method of producing aniline black.
This method is also inapplicable to the dyeing of fabrics because not only is it
very difficult to obtain merchandise of an even color, but moreover this aniline
black rubs off, that is to say it does not adhere to the fibre.
It follows that the black of oxidation which does not rub off at all, far surpasses
in quality any other aniline black.
+
The original method has in consequence been again resumed in many instances.
As above mentioned it is, in proceeding in the customary manner, impossible to
avoid that the goods become streaky; moreover two other serious disadvantages.
ID 31

page_text: are inherent to this process. The working in the oxidation chambers is very
troublesome as the chlorine gases which are evolved are extremely disadvantageous
and injurious to the health of the operatives, moreover the fabrics which must
hang for some time in this atmosphere' filled with chlorine gases suffer appreciable
loss of durability.
Now the present invention has for its object to obviate all these difficulties and
disadvantages.
To this end the oxidising and drying process takes place in a long casing or
chamber through which the suitably prepared fabric is passed evenly stretched and
following a long path rising & descending vertically. A system of coiled pipes
maintains a suitable temperature (say 44 to 50° C) and the gases and vapours
which are evolved are drawn off equally throughout the whole length of the
apparatus. In the front part of the apparatus the oxidation and drying takes
As soon as
place fresh air of 'sny. 25° 0. temperature being admitted from below.
the inaterial to be treated reaches the rear part of the apparatus, which is entirely
closed, the fabric begins to color. At the end of the apparatus water-vessels are
placed so as to provide a damp atmosphere for the oxidised material. The fabric
then issues from the chamber or apparatus and is led over the same towards the
front.
The construction of the apparatus may be as follows:-
There may be an iron framing closed up with- wooden walls or sides in which
there are doors and windows permitting access and inspection. On the bottom may
be a system of heating pipes, and suitable rollers are placed at top and bottom for
the fabric to run over; the top rollers extend outside and have toothed wheels at
their end engaging with corresponding wheels on a shaft extending along the
apparatus and driven say by a pulley at a variable speed.
The fabric, ready for treatment, in supported by a roller or reel on the front of
the apparatus and passes into the apparatus by a slot; it is led alternately under
the bottom rollers and over the top rollers passes out by a slot at the top and back
of the chamber, is led over the roof of the apparatus drawn off over suitable rollers
& by means of drawing cylinders.
The apparatus is moreover connected with, say two, exhausters and suitable.
apertures admit fresh air; to enable the latter to be equally spread, fans work in
the chamber.
The several parts of the chamber may communicate with the exhausters by
branch pipes.
The whole may be driven by speed pulleys allowing the speed to be varied so as
to adapt the apparatus for use in treating different fabrics.
Dated this 16th day of September 1884,
W. P. THOMPSON & BOULT,
Agents.

page_text: I CARL REINHARD PREIBISCH, Doctor of philosophy, Manufacturer of the firm
of C. A. Preibisch of Reichenau near Littau, Saxony German Empire do hereby
declare the nature of this invention for "IMPROVEMENTS, IN DYEING FABRICS
ANILINE BLACK AND IN APPARATUS THEREFOR" and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement :-
Three different methods for dyeing black by means of aniline have been heretofore
known. In the oldest, chiefly used for prints the developement of the black color
is effected in so called oxidation chambers, that is to say chambers in which the
fabric impressed with the printing dye is suspended, after passing through.a drying
chamber in which the dye. dries very rapidly; the oxidation then proceeds in
accordance with certain rules determined by the degree of dryness or dampness.
This process wherein the goods are suspended, is only suited for developing.
patterns can however not be used where eotton stuffs are to be dyed black in the
ground as in that case and with this process (according to which the fabric is
suspended) light streaks or stripes remain in the fabric at those parts where the
same is not exposed to the air in a uniform state of tension and these streaks can
not be removed by subsequent manipulations.
"
>
*In cases therefore where a black ground is to be produced a second newer process
has soon been adopted in which the black colour has been developed in a steam
chest and the mordaunted fabric is oxidized simply by steaming and without
undergoing a drying process. The aniline black colour produced by this steaming
is however much inferior in beauty and purity to that produced by oxidation in
air. The third method, now universally used for drying cotton yarn in hanka
as well as in the chain is based upon the use of a metallic salt, generally potassic
chromate as an oxidizing agent in the process of producing the aniline black.
This method however is not applicable for dyeing fabrics black because not only
is it very difficult to obtain fabrics of uniform colour by it, but the black colour so
produced moreover "discolours" that is to say rubs off, as is does not adhere to the
fibre.
From all this appears that the black colour obtained by oxidation, which does
not rub off, is superior to any other aniline black.
The original method has for this reason in many instances been taken up again
for dyeing fabrics. As already mentioned streakyness of the material can not be
avoided in that process and moreover two important disadvantages are experienced.
in it. Firstly the work in the oxidation chambers is very troublesome, as the
chlorous gases which are evolved are extremely noxious and injurious to the health
of the operatives and secondly the fabrics, which have for a considerable time to
remain in an atmosphere filled with chlorous gases suffer loss of durability.

page_text: and these branch pipes are evenly distributed upon the roof of the apparatus
throughout its length (Figure 2).
In consequence of this arrangement the Chlorous and other injurious gases which
are evolved will be directly removed from the interior of the apparatus by the
shortest way and from the place where they are set free so that they cannot exert
any injurious influence upon any other part of the fabric.
Moreover the air in the locality wherein the apparatus is set up will also remain
in a satisfactory condition in consequence of the uniform and uninterrupted
exhaustion of gases and noxious yapours.
As soon as the fabric has passed through about two thirds of the apparatus it is
perfectly dry and the oxidation of the mordant has been effected, so that the
fabric begins to become coloured. Now as it is well known to be important for
the successful production of a good black that the development of the colour should
take place in a moist atmosphere this end of the apparatus is completely closed
at the lower end so that no drying current of air can enter here, furthermore several
receptacles K with water are here provided, the evaporation of the water producing
a sufficient degree of dampness,
The fabric then issues from the apparatus at its upper part and is led by guide
rollers W over the entire apparatus and to the front; during this movement it
becomes once more perfectly dry and cooled and may be folded or gathered up.
To enable the apparatus to be used with equally good results both for light and
heavy fabrics a stepped pulley C is employed so that the speed at which the fabric
moves may be reduced or increased as desired.
If the apparatus is built for very wide fabrics two narrow fabrics may be passed
through it simultaneously and side by side.
The importance of this invention is the greater as it can be used not only for
cotton goods but for half woollen also.
With the processes bitherto used in dyeing aniline black, this was not practicable
as the woollen parts assumed a dead dirty colour and absolutely lost the capacity
for being dyed to a better black.
.
In the employment of the above process and apparatus however, the weft
does not suffer any loss of brilliancy and can be dyed to any desired black tint
by logwood; goods thus produced are characterised not only by the "fastness" of
their colour and their fine appearance but their "feel" is also very soft and pliant.
The invention thus presents a marked progress in dyeing half-woollen black
likewise it may be mentioned that experiments with half silk goods have likewise
given favorable results.
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. The herein before described method of dyeing fabrics black by aniline colours
which method consists in passing the evenly stretched fabrics treated with suitable
aniline mordants or preparations and moving in a vertically rising and descending
path, through an oxidizing apparatus in the forward and central part of which a
current of air, continuously passing from below upwards, causes the mordants or
preparations to be uniformly dried, whilst in the rearward portion of the apparatus
a suitable degree of dampness, which favours the colouration, is maintained, all the
chlorous and other, gas and vapours which would injuriously affect the fabric and
the air of the locality being drawn off directly at the point where they are evolved
and conveyed away from the apparatus by the shortest path.
2. An oxidising apparatus for producing aniline black in fabrics consisting in a
long chamber having at the lower part of its front and centre, apertures at its
side, the rear portion being wholly closed in, the whole chamber being fitted with
reels at top and bottom set out of line with one another, the upper set of reels
being caused to rotate uniformly by means of toothed wheels driven off one

page_text: common shaft, evenly distributed exhaust pipes opening into the roof of the
apparatus for the purpose of directly removing the gases evolved during oxidation
and which would injuriously affect the fabric and also for the removal of the air
entering at the apertures at the side, heated in passing the heating pipes and
serving to dry the fabric, together with receptacles placed in the end of the chamber
for the reception of water so as to produce a moist atmosphere,