Improve- MENTS IN THE MANUFACTURE OF COLORING MATTERS
Year: 1881

page_text: v
LETTERS PATENT to Edouard George Peter Thomas, of the Star Chemical
Works, Brentford, in the County of Middlesex, for an Invention of “Improve-
MENTS IN THE MANUFACTURE OF COLORING MATTERS."
PROVISIONAL SPECIFICATION left by the said Edouard George Peter
Thomas at the Office of the Commissioners of Patents on the 5th April
1881.
EDOUARD GEORGE PETER THOMAS, of the Star Chemical Works, Brentford, in
the County of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF COLORING
MATTERS."
In the ordinary induline processes three principal coloring matters are produced,
and their sulphonates are known in the market as induline R, induline B, and
induline 3 B, and also under other names.
The object of my Invention is to produce a new induline, which I call induline 6 B,
and I obtain it in the following manner :-
Into a suitable enamelled iron still I put together
Diazoamidobenzene
Aniline hydrochloride
Aniline pure (commercial)
100 lbs.
130 "
300 "
and I warm the mixture to (say) 40 or 50° C. so as to transform the diazoamido-
benzene into amidoazobenzene. As this transformation is accompanied by a brisk
rise of temperature, I take care by cautious management of the fire to avoid a
violent reaction, allowing the thermometer only gradually to rise to about 80 or 90°.
I then raise the temperature slowly to about 110° C., still taking care to avoid
any violent reaction, and I maintain this temperature for 4 or 5 hours when the
melt assumes a deep violet color. At this point I prefer to add 65 lbs. of aniline
hydrochloride, because I obtain a larger yield by so doing, and I raise the tempera-
ture to between 160° and 170° C., and maintain it there or thereabouts for 20 to 24
hours. The melt is then finished. Is is removed from the still, allowed to cool,

page_text: then thoroughly mixed with, say, 50 gallons of methylated spirit, and left to drain
on a suitable filter. The insoluble portion on the filter is again mixed with spirit,
and again allowed to drain, and this is repeated until the insoluble portion is
thoroughly washed, when it appears as a mass of minute glistening crystals of a
yellowish bronze color very insoluble in spirit and in aniline. This is the hydro-
chloride of the new induline. It is freed as much as possible from spirit, well
washed with hot water to remove ammonium hydrochloride, and dried.
filtrates contain induline B which is extracted, and spirit and aniline which are
recovered in the usual manner.
The
Sulphonation. In order to make the 6B soluble, 1 part is mixed with, say,
3 parts of oil of vitriol, sp. gr. about 1-840, and heated for about 6 hours at 110° C.,
when a few drops of the acid melt will be found to be quite soluble in hot water
containing a little caustic soda in excess. It is then precipitated by a large
quantity of water, washed on a filter, dissolved in water containing a sufficient
quantity of caustic soda, and evaporated to dryness.
If, instead of diazoamidobenzene which contains no hydrochloric acid, the hydro-
chloride of amidoazobenzene be used in the original melt, a similar result is
obtained, but the proportions would be :-
Hydrochloride of amidoazobenzene
Hydrochloride of aniline
Aniline
°
the remainder of the process being carried out as before.
-
-
100 lbs.
55
"
300 "
The induline 6 B is also formed when aniline bydrochloride is made to react upon
the hydrochloride of induline R. The proportions in this case would be:—
7771
Induline R, hydrochloride
Aniline hydrochloride
Aniline
-
100
'
-
45
-
200

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edouard George Peter Thomas in the Great Seal Patent
Office on the 5th October 1881.
EDOUARD GEORGE PETER THOMAS, of the Star Chemical Works, Brentford, in
the County of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF COLORING.
MATTERS.
In the ordinary induline processes three principal coloring matters are produced,
and their sulphonates are known in the market as induline R, induline B, and
induline 3 B, and also under other names.
The object of my Invention is to produce a new induline, which I call induline 6 B,
and I obtain it in the following manner :-
Into a suitable enamelled iron still I put together
Diazoamidobenzene
Aniline hydrochloride
Aniline pure (commercial)
100 lbs.
130 "
300 "
and I warm the mixture to (say) 40 or 50° C. so as to transformn the diazoamido-
benzene into amidoazobenzene. As this transformation is accompanied by a brisk
rise of temperature, I take care by cautious management of the fire to avoid a
violent reaction, allowing the thermometer only gradually to rise to about 80
or 90° C. I then raise the temperature slowly to about 110° C., still taking care to
avoid any violent reaction, and I maintain this temperature for 4 or 5 hours, when
the melt assumes a deep violet color due to the formation of induline R. At this
point I prefer to add 65 lbs. of aniline hydrochloride, because I obtain a larger
yield of induline 6 B by so doing, and I raise the temperature to between 160°
and 170° C., and maintain it there or thereabouts for 20 to 24 hours. The melt is
then finished. It is removed from the still, allowed to cool, then thoroughly mixed
with, say, 50 gallons of methylated spirit, and left to drain on a suitable filter.
The insoluble portion on the filter is again mixed with spirit, and again allowed to
drain, and this is repeated until the insoluble portion is thoroughly washed, when
it appears as a mass of minute glistening crystals of a yellowish brown color very
insoluble in spirit and in aniline. This is the hydrochloride of the new induline.
It is freed as much as possible from spirit, well washed with hot water to remove
ammonium bydrochloride, and dried. The filtrates contain induline B, which
is extracted, and spirit and aniline which are recovered in the usual manner.
Sulphonation. In order to make the 6 B soluble in water, 1 part is mixed with,
say, 3 parts of oil of vitriol sp. gr. about 1840, and heated for about 6 hours at
110° C, when a few drops of the acid melt will be found to be quite soluble in hot
water containing a little caustic soda in excess. It is then precipitated by a large
quantity of water, washed on a filter, dissolved in water containing a sufficient
quantity of caustic soda, and evaporated to dryness.
If instead of diazoamidobenzene which contains no hydrochloric acid the hydro-
chloride of amidoazobenzene be used in the original melt a similar result is
obtained, but the proportions would be :-
Hydrochloride of amidoazobenzene
100 lbs.

page_text: The induline 6 B is also formed when aniline hydrochloride is made to react
upon the hydrochloride of induline R. The proportions in this case would
Induline B. hydrochloride.
100 ha
Induline R. hydrochloride
Aniline hydrochloride
Aniline
100 lbs
دو
45
200
""
The temperature is at once raised to between 160° and 170°, and the remainder
of the operation carried out as already described.
This new coloring matter, which I call induline 6 B, differs from the indulines
previously known
In the very different shade, viz., greenish blue, which it imparts to textile
fabrics.
In the crystalline form of its hydrochloride.
In the almost complete insolubility of its hydrochloride in alcohol and aniline.
In its chemical composition; induline R as a base is represented by the
formula C, H, N³, whilst the formula of the new induline 6 B is C3, H27, N5. It
may be regarded as a condensation product of two molecules of the former with
elimination of ammonia (2 C18 H15 N³° C3% H27_N + NH3).
=
The process which I prefer for the manufacture of induline 6 B is the one first
described; it differs from the ordinary induline process in three main particulars,
viz., the much longer time devoted to the operation, the careful regulation of the
temperature as prescribed, and the largely increased proportion of aniline hydro-
chloride employed. In the charge first put into the still there is more aniline
hydrochloride than is usual, and by the addition which I subsequently make this
excess over the usual proportions is largely increased.
Having thus described the nature of my said Invention and the manner of
performing the same, I would have it understood that I claim my improved
manufacture, the coloring matter or dye stuff which I have produced, being the
new product to which I have given the name "induline 6 B," and the processes for
the manufacture of induline 6 B, substantially as herein described.
In witness whereof, I, the said Edouard George Peter Thomas, have hereunto
set my hand and seal, this First day of October, in the year of our Lord
One thousand eight hundred and eighty one.
EDOUARD G. P. THOMAS. (L.S.)