Manufacture of Mordant Dyestuffs from Anthraflavic and Isoanthraflavic Acids.
Year: 1898

page_text: Date of Application, 17th Mar., 1898
Complete Specification Left, 9th July, 1898-Accepted, 10th Sept.,
1898
PROVISIONAL SPECIFICATION.
Manufacture of Mordant Dyestuffs from Anthraflavic and
Isoanthraflavic Acids.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the
aature of this invention (as communicated to me from abroad by The Farbwerke
vormals: Meister Lucius and Brüning of Hoechst a/Main, in the Empire of
Germany, Chemical Manufacturers), to be as follows:-
acid
Starting from the anthraflavic and isoanthraflavic acids, the two isomeric
dioxyanthraquinones, there are obtained by sulphonation and nitration the two
isomeric dinitrodisulphonic acids, the dinitroanthraflavine-disulphonic
when reduced, are
and the dinitroisoanthraflavine-disulphonic acid, which
transformed into the corresponding amido-sulphonic acids. By treating these
amido-oxy-anthraquinone-sulphonic acids in an acid, aqueous alkaline or neutral
solution with gently acting oxidising agents, the amido-groups are easily
eliminated and the result gives two isomeric tetra-oxyanthraquinone-disulphonic
acids, which derive from two new isomeric tetra-oxyanthraquinones.
I. MANUFACTURE OF DINITRO-ANTHRAFLAVINE-DISULPHONIC ACID AND DIAMIDO-
ANTHRAFLAVINE-DISULPHONIC ACID.
10 parts by weight of anthraflavic acid are introduced into 80 to 100 parts by
weight of fuming sulphuric acid containing 10 to 20 per cent. of SO, and are
heated until soluble in water (110° to 120° C.).
Without
From this results the disulphonic acid of the anthraflavic acid.
molecules of nitric acid, preferably
isolating the former and after cooling,
nitration acid, are slowly run in while stirring and cooling at the same time and
the whole is finally heated for a short time to 40 to 60° C. in order to complete the
nitration.
The sulphonic acid solution is poured into water, filtered and salted out.
The dinitroanthraflavine-disulphonic acid is characterised by good crystallising
potassium salts.
If the raw acid be dissolved in a diluted solution of potassium carbonate, then
from the yellow-red solution not too diluted is obtained with acetic acid the neutral
potassium salt, crystallising in splendid red needles, which in its anhydrous state,
has the constitution :
CH.O. (OKa). (SO.Ka), (NO2)2.

page_text: Warm concentrated sulphuric acid dissolves the sulphonic acid with a greenish-
yellow colour.
A strong excess of acid precipitates it from the aqueous solution.
With regard to the transforming into diamido-anthraflavine-disulphonic acid, the
solution of the dinitrosulphonic acid in concentrated sulphuric acid, as obtained in
its manufacture, is diluted with water, to which is slowly added, while gently
heated, the calculated quantity of a solution of stannous chloride or any other suitable
reduction agents.
The solution assumes after a short time an intense blue-red colour and the
diamido-anthraflavine disulphonic acid is best isolated by salting out with chloride
of potassium.
The diamidoanthraflavinedisulphonic acid is characterised by its acid potassium
salt. The latter is obtained, if the raw acid above produced be taken up hot in a
diluted solution of potassium carbonate and acidified with acetic acid. It crystallises
in beautiful red needles and in its anhydrous state has the constitution of CH₂O₂
(OH)2 (NH2)2 (SO,Ka)2. It is soluble in water with a red colour, turning on
addition of alkali into an intense blue red. If concentrated sulphuric acid be
poured on it, it turns grey in consequence of the formation of a sulphate soluble
with difficulty; the sulphate is soluble however, when gently warmed in sulphuric
acid, with an orange colour.
II. MANUFACTURE OF
DINITROISOANTHRAFLAVINEDISULPHONIC
ANTHRAFLAVINEDISULPHONIC ACID.
ACID AND DIAMIDO180-
The manufacture of dinitroisoanthraflavinedisulphonic acid is carried out by
using isoanthraflavic acid under exactly the same conditions as those mentioned in
the manufacture of dinitroanthraflavinedisulphonic acid. By salting out the product
of reaction dissolved in water with chloride of potassium, the acid potassium salt
of the nitroisoanthraflavinesulphonic acid is obtained, which in order to be purified,
may be precipitated from its alkaline solution with mineral acids and recrystallised
from water. It is thus obtained in light orange crystals, easily soluble in water
(even cold) with an orange yellow colour and having in the anhydrous state the
constitution of C₁₂O₂ (OH), (SO₂Ka), (NO2)2. Alkalies turn its aqueous
solution yellow-red on account of the forination of the neutral salt which is less
crystallisable.
The manufacture and isolation of the diamidoisoanthraflavinedisulphonic acid is
carried out exactly according to the example given in the manufacture of diamidoanthra-
flavinedisulphonic acid. In order to purify the product the raw salt obtained as
above is transformed by precipitating its alkaline solution with acids into the acid
salt of potassium, crystallising in red crystals. The latter does not crystallise so
well as the corresponding salt from anthraflavic acid and is soluble in hot water
with a yellow-red colour, turning on addition of alkalies into a beautiful blue-red.
Warm concentrated sulphuric acid dissolves it with a light yellow colour.
III. THE TRANSFORMING OF AMIDOSULPHONIC ACIDS INTO TETRAOXYANTHRAQUINONE-
SULPHONIC ACIDS.
Of the various gently acting oxydising agents, which cause, according to their
specific mode of application in neutral, acid, or alkaline solution, the substitution of
the hydroxyl- for the amido- groups, the following may be mentioned peroxide
of lead, peroxide of manganese, chloride of lime, ferric salts, chromates, persulphates,
nitric acid etc. etc. The following examples illustrate the process :-
:
1) Diamidoanthraflavinedisulphonic acid is dissolved in just the requisite quantity
of hot water, acidified, to which is added while actively stirring, a quantity
corresponding to 2 to 3 molecules of peroxide of lead or peroxide of manganese,
preferably in form of a fine paste. The intense red colour of the diamidosulphonic
acid, when gently heated, disappears almost suddenly, giving way to an orange-

page_text: yellow colour. When this point is reached, the reaction is complete. From the
filtered solution chloride of potassium or common salt separate the acid-salt-of the
tetraoxyanthraquinonedisulphonic acid in form of a yellow brown crystalline
precipitate.
2) Diamidoanthraflavinedisulphonic acid is dissolved in about twenty times the
quantity of concentrated sulphuric acid; to which are introduced 2 molecules of
finely powdered peroxide of manganese while cooling. After a short time the
solution assumes an olive colour. The product of reaction is still stirred for some
time at ordinary temperature and then poured into water. On being heated, the
olive coloured solution turns rapidly into the red brown tint of the tetraoxysulphonic
acid, which is isolated according to Example 1.
3) 10 parts by weight of diamidoanthraflavinedisulphonic acid (acid salt of
potassium) dissolved in hot acidified water, to which is added the calculated
quantity of any ferric salt, for instance: ferric chloride, ferric sulphate or
ferricyanide of potassium. After boiling for a short time the solution becomes
brown-green and the formation of the tetraoxyanthraquinonedisulphonic acid, which
can be isolated from the filtered solution by salting out, is complete. The product
obtained according to the examples given or by means of others of the above
mentioned oxidising agents, is the acid potassium salt of a new tetraoxyanthra-
quinonedisulphonic acid, which is pure in most cases. It is soluble with difficulty
in cold, more easily in boiling water with a reddish yellow colour, from which it
can be crystallised, on addition of a few drops of a solution of chloride of potassium,
in red-brown crystals. Alkalies change it into the red neutral salt, which is
precipitated by an excess of alkali from the aqueous solution in the form of red
crystalline laminae.
The tetraoxyanthraquinonedisulphonic acid from anthraflavic acid is a valuable
mordant and acid dyestuff. Its acid colour can be subsequently shaded with
metallic salts. Treated with alum it produces blue-red shades, with chromium
fluoride pure violet shades, which are quite fast to milling and light.
4.) If the diamidoisoanthraflavinedisulphonic acid be boiled as in Example No. 3,
in an acidified aqueous solution with the calculated quantity of a ferric salt (ferric
chloride, ferric sulphate, etc. etc.) until the solution is brown-green, the
tetraoxyanthraquinonedisulphonic acid, isomeric with the one above mentioned, is
easily isolated in form of its acid potassium salt which may be readily obtained pure
by recrystallisation or by decomposition of the neutral salt.
5.) Into the slightly acidified aqueous solution of diamidoisoanthraflavine-
disulphonic acid, heated to 40° or 60° C. is introduced the calculated quantity of
ammonium persulphate, dissolved in a little water. After a short time the reaction
is complete and the colour of the solution, at first of an intense red, has changed
into a yellow-orange one. The isolating of the tetraoxyanthraquinonedisulphonic
acid is effected by salting out. The acid potassium salt of this new tetraoxy-
anthraquinonedisulphonic acid from isoanthraflavic acid has on the whole the
properties of its isomeride from diamidoanthraflavinedisulphonic acid. It is easily
soluble in hot water with a red-yellow colour, from which it crystallises on addition
of a few drops of chloride of potassium in light brown needles. Alkalies change
it, in aqueous solution, into the neutral salt easily soluble with a violet colour,
which can only be precipitated in form of violet flakes by a great excess of alkali.
In concentrated sulphuric acid the sulphonic acid is soluble with a fiery bluish-red
colour and weak light-green fluorescence.
From a tinctorial point of view the product is the analogue of the isomeric
tetraoxyanthraquinonedisulphonic acid from anthraflavic acid. The corresponding
dye-lakes are throughout of a somewhat more reddish tint than those of the
latter.
ABEL & IMRAY,
Agents for the Applicant.

page_text: Manufacture of Mordant Dyestuffs from Anthraflavic and
Isoanthraflavic Acids.
,
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the
nature of this invention (as communicated to me from abroad by The Farbwerke
vormals: Meister Lucius and Brüning of Hoechst a/ Main, in the Empire of
Germany, Chemical Manufacturers), and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
Starting from the anthraflavic and isoanthraflavic acids, the two isomeric
dioxyanthaquinones there are obtained by sulphonation and nitration the two
isomeric dinitrodisulphonic acids, the dinitroanthraflavine-disulphonic acid and the
dinitroisoanthraflavine-disulphonic acid, which when reduced, are transformed into
By treating these amido-oxy-
the corresponding amido-sulphonic acids.
anthraquinone-sulphonic acids in an acid, aqueous alkaline or neutral solution with
gently acting oxidising agents, the amido-groups are easily eliminated and the
result gives two isomeric tetraoxyanthraquinone-disulphonic acids, which derive
from two new isomeric tetraoxyanthraquinones.
I. MANUFACTURE OF DINITROANTHRA FLAVINE-DISULPHONIC ACID AND DIAMIDOANTHRA-
FLAVINE-DISULPHONIC ACID.
10 parts by weight of anthraflavic acid are introduced into 80 to 100 parts by
weight of fuming sulphuric acid containing 10 to 20 per cent. of SO, and are
heated until soluble in water) 110° to 120° C.).
From this results the disulphonic acid of the anthraflavic acid. Without isolating
the former and after cooling, 2 molecules of nitric acid, preferably nitration acid,
are slowly run in while stirring and cooling at the same time and the whole is
finally heated for a short time to 40 to 60° C. in order to complete the nitration.
The sulphonic acid solution is poured into water, filtered and salted out.
The
dinitroanthraflavine-disulphonic acid is characterised by good crystallising
potassium salts.
If the raw acid be dissolved in a diluted solution of potassium carbonate, then
from the yellow-red solution not too diluted is obtained with acetic acid the
neutral potassium salt, crystallising in splendid red needles, which in its anhydrous
state. has the constitution:
The dinitroanthraflavine-disulphonic acid itself is easily so
brown-yellow colour, turning into green-yellow on addition of alkali.
Warm concentrated sulphuric acid dissolves the sulphonic acid with a greenish- 4
yellow colour.
A strong excess of acid precipitates it from the aqueous solution.

page_text: With regard to the transfcin ing into diamidoanthi aflavine-disulphonic acid, the
solution of the dinitrosulphonic acid in concentrated sulphuric acid, as obtained in
its manufacture, is diluted with water, to which is slowly added, while gently
heated, the calculated quantity of a solution of stannous chloride or any other
suitable reduction agent.
The solution assumes after a short time an intense blue-red colour and the
diamidoanthraflavine disulphonic acid is best isolated by salting out with chloride
of potassium.
The diamidoanthraflavinedisulphonic acid is characterised by its acid potassium
salt. The latter is obtained if the raw acid above produced be taken up hot in a
diluted solution of potassium carbonate and acidified with acetic acid. It crystallises
in beautiful red needles and in its anhydrous state has the constitution of
CH₂O (OH), (NH2)2 (SO,Ka),. It is soluble in water with a red colour,
turning on addition of alkali into an intense blue red. If concentrated sulphuric
acid be poured on it, it turns grey in consequence of the formation of a sulphate
soluble with difficulty; the sulphate is soluble however, when gently warmed in
sulphuric acid, with an orange colour.
11. MANUFACTURE OF
DINITROISOANTHRAFLAVINE-DISULPHONIC
ANTHRAFLAVINEDISULPHONIC ACID.
ACID AND DIAMIDOISO-
The manufacture of dinitroisoanthraflavinedisulphonic acid is carried out by using
isoanthraflavic acid under exactly the same conditions as those mentioned in the
manufacture of dinitroanthraflavinedisulphonic acid. By salting out the product of
reaction dissolved in water with chloride of potassium, the acid potassium salt of
the nitroisoanthraflavinesulphonic acid is obtained, which in order to be purified,
may be precipitated from its alkaline solution with mineral acids and recrystallised
from water. It is thus obtained in light orange crystals, easily soluble in water
(even cold) with an orange yellow colour and having in the anhydrous state the
constitution of C₁H₂O₂(OH)2 (SO₂Ka)2 (NO2) 2. Alkalies turn its aqueous solution
yellow-red on account of the formation of the neutral salt which is less
crystallisable.
The manufacture and isolation of the diamidoisoanthra flavinedisulphonic acid is
carried out exactly according to the example given in the manufacture of diamido-
anthraflavinedisulphonic acid. In order to purify the product the raw salt obtained
as above is transformed by precipitating its alkaline solution with acids into the
acid salt of potassium, crystallising in red crystals. The latter does not crystallise
so well as the corresponding salt from anthraflavic acid and is soluble in hot water
with a yellow-red colour, turning on addition of alkalies into a beautiful blue-red.
Warm concentrated sulphuric acid dissolves it with a light yellow colour.
III. THE TRANSFORMING OF
AMIDOSULPHONIC ACIDS INTO TETRAOXYANTHRAQUINONE-
SULPHONIC ACIDS.
Of the various gently acting oxydising agents, which cause, according to their
specific mode of application in neutral, acid, or alkaline solution, the substitution
of the hydroxyl- for the amido-groups, the following may be mentioned. Peroxide
of lead, peroxide of manganese, chloride of lime, ferric salts, chromates,
the
persulphates nitric acid etc.
The following examples illustrate
process :-
etc.
1) Diamidoanthraflavinedisulphonic acid is dissolved in just the requisite
quantity of hot water, acidified, to which is added while actively stirring, a quantity
corresponding to 2 to 3 molecules of peroxide of lead or peroxide of manganese,
preferably in form of a fine paste. The intense red colour of the diamidosulphonic
acid, when gently heated, disappears almost suddenly, giving way to an orange-
yellow colour. When this point is reached, the reaction is complete. From the
filtered solution chloride of potassium or common salt separate the acid salt of the

page_text: tetraoxyanthraquinonedisulphonic acid in form of a yellow brown crystalline
precipitate.
2) Diamidoanthraflavinedisulphonic acid is dissolved in about twenty times the
quantity of concentrated sulphuric acid, to which are introduced 2 molecules of
finely powdered peroxide of manganese while cooling. After a short time the solution
assumes an olive colour. The product of reaction is still stirred for some time at
ordinary temperature and then poured into water. On being heated, the olive
coloured solution turns rapidly into the red brown tint of the tetraoxysulphonic
acid, which is isolated according to Example 1.
3) 10 parts by weight of diamidoanthraflavinedisulphonic acid (acid salt of
potassium) dissolved in hot acidified water, to which is added the calculated quantity
of any ferric salt, for instance: ferric chloride, ferric sulphate or ferri-cyanide of
potassium. After boiling for a short time the solution becomes brown-green and the
formation of the tetraoxyanthraquinonedisulphonic acid, which can be isolated from
the filtered solution by salting out, is complete. The product obtained according
to the examples given or by means of others of the above mentioned oxidising
agents, is the acid potassium salt of a new tetraoxyanthraquinonedisulphonic acid,
which is pure in most cases. It is soluble with difficulty in cold, more easily in
boiling water with a reddish yellow colour, from which it can be crystallised, on
addition of a few drops of a solution of chloride of potassium, in red-brown crystals.
Alkalies change into the red neutral salt, which is precipitated by an excess of
alkali from the aqueous solution in the form of red crystalline laminae.
The tetraoxyanthraquinonedisulphonic acid from anthraflavic acid is a valuable
mordant and acid dyestuff. Its acid colour can be subsequently shaded with
metallic salts. Treated with alum it produces blue-red shades, with chromium
fluoride pure violet shades, which are quite fast to milling and light.
4) If the diamidoisoanthraflavinedisulphonic acid be boiled as in Example No. 3
in an acidified aqueous solution with the calculated quantity of a ferric salt (ferric
chloride, ferric sulphate, etc. etc.) until the solution is brown-green, the
tetraoxyanthraquinonedisulphonic acid, isomeric with the one above mentioned, is
easily isolated in form of its acid potassium salt which may be readily obtained pure
by recrystallisation or by decomposition of the neutral salt.
5) Into the slightly acidified aqueous solution of diamidoisoanthraflavinedisulphonic
acid, heated to 40° or 60° C. is introduced the calculated quantity of ammonium
persulphate, dissolved in a little water. After a short time the reaction is complete
and the colour of the solution, at first of an intense red, has changed into a
yellow-orange one. The isolating of the tetraoxyanthraquinonedisulphonic acid
is effected by salting out. The acid potassium salt of this new tetraoxyanthra-
quinonedisulphonic acid from isoanthraflavic acid has on the whole the properties
of its isomeride from diamidoanthraflavinedisulphonic acid. It is easily soluble in
hot water with a red-yellow colour, from which it crystallises on addition of a few
drops of chloride of potassium in light brown needles. Alkalies change it, in
aqueous solution, into the neutral salt easily soluble with a violet colour, which can
only be precipitated in form of violet flakes by a great excess of alkali. In
concentrated sulphuric acid, the sulphonic acid is soluble with a fiery bluish-red
colour and weak light-green fluorescence.
From a tinctorial point of view the product is the analogue of the isomeric
tetraoxyanthraquinonedisulphonic acid from anthraflavic acid. The corresponding
dye lakes are throughout of a somewhat more reddish tint than those of the
latter.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The herein described manufacture of two new isomeric tetraoxyanthraquinone-
disulphonic acids from anthraflavic acid and isoanthraflavic acid by transforming

page_text: fuming sulphuric acid-nitrating these disulphonic acids to produce the corres-
ponding dinitro-disulphonic acids-reducing these dinitrodisulphonic acids by
reducing agents to produce the corresponding diamido disulphonic acids-and finally
converting the diamido-anthraflavic disulphonic acid or diamido-isoanthraflavic
disulphonic acid respectively into the two isomeric tetraoxyanthraquinonedisulphonic
acids by treatment with appropriate oxidising agents.
2. The compounds manufactured as set forth in Claim 1.