Improvements in the Manufacture or Production of Coloring Matters Derived from Anthraquinone.
Year: 1892

page_text: Date of Application, 4th Oct., 1892
Complete Specification Left, 4th July, 1893-Accepted, 5th Aug., 1893
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE FARBENFABRIKEN vormals FRIEDRICH
BAYER & Co., of Elberfeld, in the Empire of Germany.]
Improvements in the Manufacture or Production of Coloring
Matters Derived from Anthraquinone.
I HENRY EDWARD NEWTON of the Office for Patents, 6 Bream's Buildings,
Chancery Lane in the County of London, Patent Agent, do hereby declare the
nature of this invention to be as follows:-
It is well known that in heating dinitroanthraquinone, especially di orthonitro-
anthraquinone (described by Römer in the Berichte der Deutschen Chemischen
Gesellschaft, XVI, 363) with concentrated or fuming sulphuric acid, dye stuffs are
obtained which produce on wool mordanted with chromium salts, shades from
reddish blue to greenish blue, according to the conditions on which the production
thereof is effected, as described in the Specification of the German Letters Patent
No. 6526, in the Berichte der Deutschen Chemischen Gesellschaft, volume 4,
page 229 and 231; volume 15, page 1522 and 1801; volume 17, page 891.
It is also known that the above methods hitherto published, probably owing to
the complex reactions there taking place, do not yield technically sufficient amounts
of such coloring matters that will produce shades of the purity desired. The
German application for Letters Patent No. B 12599, relates to a process by
which better results are said to be obtainable.
My foreign correspondents have now found that the formation of dye stuffs from
dinitroanthraquinone and sulphuric acid, proceeds more readily, if it be effected
in presence of sulphur finely powdered, for instance, flowers of sulphur. They have
further ascertained that sulphur sesquioxide, obtained by dissolving sulphur in
fuming sulphuric acid, acts in a still better manner, probably because, in the
employment of sulphur sesquioxide during the reaction, sulphur in the so-called
"status nascendi" is separated. The conversion of dinitro-anthraquinone then
takes place even at ordinary temperature.
The favorable influence caused by the sulphur, or sulphur sesquioxide, appears in
all different modifications of treating dinitroanthraquinone, and partly in a very
remarkable manner. It is of technical value that the formation of dye stuffs
proceeds at a temperature considerably lower, and with much greater ease, than
when the methods hitherto known are employed, and that coloring matters are
produced the shades of which are remarkable for their great brightness.
The following example is given in order to illustrate the method of treating di
orthonitroanthraquinone in this new manner, the parts mentioned being by weight.
10 parts of diorthonitroanthraquinone are stirred into 300 parts of sulphuric and
monohydrate, and, on stirring, a solution, prepared by dissolving 4 parts of sulphur
in 50 parts of fuming sulphuric acid, containing 40 per cent. of anhydride, is added
to the above mixture. The reaction and formation of dye stuff already begins at
ordinary temperatures; for instance, 20 degrees centigrade. In order to complete
the production of coloring matter within a short time, the mixture is heated to form
about 80 to 100 degrees centigrade, sulphur dioxide being disengaged, and the
sulphuric solution acquiring a brownish color.
The resulting mass is then poured into cold water, and the dye stuff precipitated
is filtered off. It is re-dissolved in sodium carbonate, and after filtering the
alkaline solution in order to remove the sulphur, if it be there, the dye stuff is
precipitated by acidulating the alkaline filtrate, and filtered off.
The coloring matter thus obtained forms a paste of dark violet color, which is
almost insoluble in cold water, and is dissolved by hot water more easily and with

page_text: a violet color. It dissolves in soda lye with a brightly violet blue color in con-
centrated sulphuric acid, and, in fuming sulphuric acid containing 20 per cent. of
anhydride, with a brownish yellow color. It produces blue shades on wool
mordanted with chromium salts.
If the temperature employed in the above example be raised, at least, to about
160 degrees centigrade, the mass acquires a grass green color.
On pouring into water, a beautiful reddish violet solution of a sulpho acid results,
which can be isolated by salting out. It is soluble in soda lye with a pure greenish
blue color; in concentrated pure sulphuric acid with a dull violet color and a red
fluorescence; in fuming sulphuric acid containing 20 per cent. of anhydride, with a
green color and a reddish blue fluorescence. It dyes wool mordanted with
chromium salts a pure blue.
On raising the temperature still more in the foregoing example (from 170 to
180 degrees centigrate), the last named sulpho acid is changed into a coloring
matter which is insoluble in water, and separates in dark violet flakes, when poured
into water. It dissolves in soda lye with greenish-blue color; in concentrated
sulphuric acid with violet-red color; in fuming sulphuric acid containing 20 per cent.
of anhydride, with bluish violet color; and it produces greenish blue shades on wool
mordanted with chromium salts.
The proportions mentioned in the above example can be varied, and by varying
the conditions on which the conversion is effected, different products are obtained,
which are more or less soluble in water or insoluble in water, and yield shades from
violet to greenish blue on wool mordanted with chromium salts. It is not necessary
to employ dinitroanthraquinone in a pure state, but the raw mixture of nitro-
anthraquinones which results, in nitrating anthraquinone dissolved in sulphuric acid
likewise can be used for such purposes as herein before defined. My foreign
correspondents have further found that the nitro anthraquinone sulpho acids which
are obtained by nitrating anthraquinone sulpho acids, can also be employed in this
process.
Dated this 4th day of October 1802
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture or Production of Coloring
Matters derived from Anthraquinone.
I, HENRY EDWARD NEWTON of The Office for Patents, 6 Bream's Buildings
Chancery Lane, in the County of London, 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 ascertained in and by the following statement :-
It is well known that on heating dinitroanthraquinone, especially diortho nitro-
anthraquinone (described by Römer in the Berichte der Deutschen Chemischen
Gesellschaft, XVI, 363), with concentrated or fuming sulphuric acid, dye stuffs are
obtained, which produce shades varying from reddish blue to greenish blue on
wool mordanted with chromium salts, as described in the Specification of the
German Letters Patent No. 6526, and in the Berichte der Deutschen Chemischen
Gesellschaft, volume 4, pages 229 and 231; volume 15, pages 1522 and 1801;
volume 17, page 891.
It is also known, however, that the methods hitherto described, probably owing
to the complexity of the interactions which take place, do not afford technically
satisfactory results, especially in so far as concerns the purity of shade of the
resulting colouring matters.
A process said to afford better results, has been recently described in the German
Patent No. 67102.

page_text: sulphur sesquioxide, taking care (by cooling) that the temperature does not rise
above 45 degrees centigrade. The action is completed when the temperature no
longer rises. After adding from 150 to 200 parts of sulphuric acid (60 degrees
Baumé), the sulphuric mixture is poured into cold water. The dye stuff which
separates is filtered off, and washed, in order to remove the adherent acid. It is a
dark violet-brown coloured precipitate, which dissolves in soda lye, producing
a greenish-blue coloured liquid, and, in concentrated sulphuric acid, producing
a brownish coloured liquid. It produces greenish-blue shades on wool mordanted
with chromium salts.
The proportions mentioned in the above examples, the temperature indicated,
and the strength of the acids employed therein, can be varied, and, by varying the
conditions under which the conversions are effected, different products are obtained,
which are either more or less soluble, or insoluble in water, and produce shades
varying from violet to greenish-blue on wool mordanted with chromium salts. The
researches of my foreign correspondents shew, also, that, instead of sulphur,
substances can be used such as are capable of giving sulphur sesquioxide, when in
presence of fuming sulphuric acid or sulphuric anhydride; for instance, hydrogen
sulphide, hydrogen super sulphide (H,S,) sulphur monochloride (S,Cl₂), salts of
thiosulphuric acid or the like, can be employed.
Such or similar modifications do not alter the nature of this invention, which
relates to the production of dye-stuffs by treating di-ortho-nitroanthraquinone, or
other dinitro anthraquinones, or raw technical nitro anthraquinones, or nitro-
anthraquinone sulpho acids, with sulphur sesquioxide, or with solutions of sulphur
in fuming sulphuric acid, or with substances capable of giving sulphur sesquioxide
in presence of fuming sulphuric acid or sulphuric anhydride, the said processes
being carried out in presence of suitable solvents or diluents, riz. :-concentrated
sulphuric acid, fuming sulphuric acid, or sulphuric anhydride.
The feature of special value in this new process is, the fact that it affords
products which are far superior to those obtainable under analogous conditions,
without the use of sulphur or sulphur sesquioxide, for instance, if, in the process
described in the above second example, sulphur or sulphur sesquioxide be not used.
My foreign correspondents have ascertained, that in some cases, for instance, on
following the directions given in the above first example, the action does not
proceed in the said manner, if sulphur sesquioxide, or sulphur, be not employed.
The high practical value of this new process, consists in that the products
obtained by it are formed in a very simple manner, and in a pure state, and that
they yield shades of extraordinary purity. In this process, it is not necessary to
employ dinitroanthraquinone in a pure state, as mixtures thereof, or the raw mixture
of nitroanthraquinones, which is formed in nitrating anthraquinone dissolved in
sulphuric acid, or in other ways, can also be used for the purposes hereinbefore
defined.
My foreign correspondents have further found that nitro-anthraquinone sulpho
acids can also be employed in this process.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed (as communicated to me
from abroad), I declare that what I claim is :-
1. The production of dye-stuffs by treating-in presence of suitable solvents or
diluents, viz., concentrated sulphuric acid, or fuming sulphuric acid, or sulphuric
anhydride-dinitro anthraquinones, especially di-ortho-nitroanthraquinone described
by Roemer in the Berichte der Deutschen Chemischen Gesellschaft Volume XVI,
page 363, or raw technical nitroanthraquinones, or nitro anthraquinone sulpho
acids, with sulphur sesquioxide, or with a solution of sulphur in fuming sulphuric
acid, or with such substances as are capable of giving sulphur sesquioxide, when
they are employed together with fuming sulphuric acid or sulphuric anhydride,
and subsequently isolating the resulting colouring matters in a suitable manner.

page_text: 2. As new products of manufacture, the new colouring matters prepared by the
processes hereinbefore defined, or by any other means producing the same result.
Dated this 1st day of July 1893.
NEWTON & SON,
Agents for the Applicant.