Improvements in or relating to the Dyeing of Yarn.
Year: 1890

page_text: Date of Application, 25th Mar., 1890-Accepted, 26th Apr., 1890
COME LEIE SPECIFICATION.
Improvements in or relating to the Dyeing of Yarn.
A communication from ADOLF and MARTIN KOBLENZER, of Augsburg (Pfersee),
Germany, Manufacturers.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex, M.I.M.E.,
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:
The object of this invention is a process for dyeing cotton yarn directly as it is
spun, and while it is yet in the form of cops, thus obviating the necessity of forming
it into skeins. This is a highly important feature as it effects a saving of all the time
employed and the expense involved in putting up the yarn into skeins previously to
dyeing it, and in winding it upon the spools again when the dyeing is completed.
Many attempts have hitherto been made to accomplish such a result but none of the
remedies suggested have proved workable in practice.
All methods hitherto proposed for the solution of this problem were mechanical ones.
This invention on the contrary relates to a chemical process whereby the aim it is
sought to attain is actually fulfilled in a thorough and effective manner.
The process herein described mainly consists in submitting the yarns while wound
in the form of cops to two distinct operations; a mordant being prepared for the
purpose, quite independent of the dye.
This separation of the mordant from the dye may appear trifling and yet it is owing
to it only, that the desired purpose is attained. It has been demonstrated beyond
doubt, by a number of experiments that both the total omission of the mordant and
the use of a mordant mixed with the dye-two methods which may fairly be regarded
as equivalent invariably lead to failure; the drawback being that oven supposing
the different yarns capable of being dyed uniformly and without specks or patches the
outer yarns are always more fully impregnated with dye than those nearer to the
core.
Primuline may be used for a mordant while for dyeing suitable salts such as naphthol
and naphthylamine may be employed.
The process is carried out as follows;-
The cops after being thoroughly treated in a boiler, and washed, so as to be freed
from all fatty substances and other impurities are placed in a boiler containing the
mordant which may consist of 5 parts of primuline and 5 parts of common salt for
cach 100 parts of water. This mordant is so proportioned that its weight is equal to
the weight of the yarn to be dyed. The whole is now thoroughly treated for several
hours under from 2 to 3 atmospheres of pressure with the assistance of a steam pump.
After this the yarn is washed for several hours continuously with water cooled by
means of ice to from 4 to 5°. It is then placed in a cold bath of 10 parts of water,
1. part of nitrite of soda and 2 parts of sulphuric acid and then washed once more as
above.
When the mordant has thus thoroughly penetrated into and is fixed in the yarn―
which thereby acquires a uniform yellow sulphur-like hue-the dyeing proper may be
proceeded with, with salis adapted to impart the desired colors, such as naphthol and
naphthylamine, and is also effected under a pressure of from 2 to 3 atmospheres. The
quantities must of course be proportioned to the shade of color it is desired to obtain
and may be determined by test.
The subsequent operations such as washing, swinging and drying take place in the
same manner as in the case of skeins.

page_text: Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondents I declare that what I claim is ;-
A process for dyeing cotton yarn while in the form of cops mainly consisting in
submitting the cotton to be dyed to a series of distinct operations it being first treated
by means of a mordant such as primuline, under a pressure of from 2 to 3 atmospheres,
then washed in a sufficiently cool water bath acidulated by means of nitrite of soda
and sulphuric acid, and finally dyed by means of suitable dyeing salts also under 2 or
3 atmospheres of pressure substantially as described.
Dated this 25th day of March 1890.
W. P. THOMPSON & BOULT,
Agents for the Applicant.