Improvements in or relating to Indigo Printing and Dyeing.
Year: 1898

page_text: Date of Application,
Mar., 1908
Complete Specification Left, 30th Sept., 1898-Accepted, 3rd Dec.,
1898
Date of Application
Complete Specification Left, 30th Sept., 1898-Accepted, 3rd Dec., 1898
PROVISIONAL SPECIFICATION..
Improvements in or relating to Indigo Printing and Dyeing.
A communication from DR. WILHELM ELBERS, of Hagen, Westfalia, in the
Empire of Germany, Managing Director..
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be
as follows:-
This invention relates to improvements upon the invention described in my
prior Specification No. 509 dated 7th January 1898, relating to a process for pro-
ducing fast gray tones in indigo printing and dyeing, characterised by applying
indigo in a finely divided state to the fibres and then steaming the fabric-for
a considerable time, if under moderate pressure, or for a short time, if under
high pressure, washing out the thickening or gum and treating it with soap.
Large quantities of animal or vegetable oils are preferably added to the colour
for printing or dyeing in order to attain greater uniformity and good appearance
of the shades. It has however been found that the fastness or permanency of
the resulting grey colour can be considerably increased by subjecting the fabric
printed or dyed that is padded with indigo, after it has been steamed and freed
from thickening or gum, to a second steaming for a considerable time under a
comparatively high pressure. The essential point is to remove by washing and
treating with malt all traces of gum or thickening from the fabric before sub-
jecting it to a second steaming operation. A much longer or frequently repeated
steaming of the unwashed fabric has far less effect than a steaming repeated
after the fabric has been completely deprived of gum or thickening (by washing
and treating with malt) between the two steaming operations. It is also impor-
tant to effect the second steaming operation at a comparatively high pressure.
The experiments show that the best results are obtained with an added pressure
of from 0.7 to 1 atm.
The following description is given by way of example:-
The fabric prepared for printing in the usual way is printed upon with a
colour constituted say as follows:-
960-900 gr. of thickening material.
20-50 gr. of indigo paste (containing 20% indigo).
20 50 gr. of olive oil.
After the printing, the fabric is steamed for two hours at 0.1 atm. pressure
then washed treated with malt and dried. It is then steamed again for 1%, hours
say, 0.7 1 atm. pressure and finished in the usual manner.
at
This treatment the second steaming operation-is important especially for
fabrics the colours of which are required to have great fastness or permanency
under friction and soap (as for instance in "washing" fabrics for dresses).
andant's evneriments have further shown, that the process gives

page_text: as woollen and silk fabrics. The indigo printing process used hitherto (for
instance, Schlieper's process) cannot be used for wool or silk. On the other
hand, the grey dye-stuffs hitherto used do not possess sufficient fastness to light.
The process: according to the present invention enables indigo to be used also
for printing on wool and silk whereby grey colours perfectly fast to light are
obtainable which hitherto could not be produced with the same degree of
durability. When working according to the present process, it must not be
forgotten that steaming at too high a pressure has an injurious effect on woollen
and silk fibres. The steaming operations must be made therefore longer and
the pressure lower.
Example. Woollen or silk fabric, prepared for printing in the usual way, is
printed upon with the following dye.
960-900 gr. of thickening material.
20 50 gr. of indigo.
20-50 gr. of olive oil.
After the printing the fabric is steamed for two hours without pressure well
washed and finished
Improvements in or relating to Indigo Printing and Dyeing.
A communication from Dr. WILHEIM ELBERS, of Hagen, Westfalia, in the
Empire of Germany, Managing Director.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered 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 ascer-
tained in and by the following statement:-
This invention relates to improvements upon the invention described in the
prior Specification, No. 509, dated 7th January, 1898, relating to a process for
producing fast grey tones in indigo printing and dyeing, characterised by apply-
ing indigo in a finely divided state to the fibres, and then steaming the fabric,
for a considerable time if under moderate pressure, or for a short time if under
high pressure,—freeing it from the thickening or gum and treating it with
soap. Large quantities of animal or vegetable oils are preferably added to the
color for printing or dyeing, in order to attain greater uniformity and good
appearance of the shades. It has, however, been found that the fastness or
permanency of the resulting grey colour can be considerably increased by the
aid of the present invention, that is, subjecting the fabric printed or dyed, that
is padded, with indigo after it has been steamed and freed from thickening or
gum, to a second steaming for a considerable time under a comparatively high
pressure. The essential point is to remove by washing and treating with malt
all traces of gum or thickening from the fabric before subjecting it to a second
steaming operation. A much longer or frequently repeated steaming of the
unwashed fabric has far less effect than a steaming repeated after the fabric
has been completely deprived of gum or thickening, (by washing and treating.
with malt) between the two steaming operations. It is also important to effect
the second steaming operation at a comparatively high pressure. The experi

page_text: BOULT & WADE,
Agents for the Applicant.