The Manufacture or Production of Anthraquinone Derivatives.
Year: 1894

page_text: Date of Application, 16th Jan., 1894
Complete Specification Left, 12th Oct., 1894-Accepted, 17th Nov., 1894
PROVISIONAL SPECIFICATION.
[Communicate from abroad by THE FARBENFABRIKEN, vormals FRIEDRICH
BAYER & Co., of Elberfeld, in the Empire of Germany.]
The Manufacture or Production of Anthraquinone Derivatives.
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:-
My foreign correspondents have found that not only nitro and amido
anthraquinones can be converted into hydroxyanthraquinones by heating with
concentrated sulphuric acid in the presence of boric acid, or similar substances,
which are transformed into boric when used in sulphuric acid solution, but that also
anthraquinone and the hydroxyanthraquinones derived therefrom react in the same
manner.
This interesting and technically valuable reaction proceeds very satisfactorily,
if, for instance, anthraquinone is used. In the latter case, quinizarin is first formed
in good quantities, and, by further oxidation, is transformed into purpurin.
One method of converting anthraquinone into quinizarin is illustrated by the
following example. The parts are by weight.
CONVERSION OF ANTHRAQUINONE INTO QUINIZARIN BY MEANS OF SULPHURIC
ACID IN THE PRESENCE OF BORIC ACID.
$
10 parts of anthraquinone are mixed with 10 parts of crystallized boric acid and
200 parts of sulphuric acid (66 degrees Bauné), and the resulting mixture is
heated. An energetic, though not violent, reaction begins at from 260 to
280 degrees centigrade, sulphur dioxide being disengaged.
The formation of quinizarin is complete within a comparatively short time,
whilst the conversion of quinizarin into purpurin necessitates heating for a longer
period. The continuance and end of the reaction is distinguishable by spectro-
scopical researches of test portions diluted with sulphuric acid.
In order to isolate the hydroxyanthraquinone, the mass is poured into water.
The separated hydroxy-product is filtered off, and, if necessary, is purified by
redissolving in alkali, precipitating with acids, and filtering off again.
The proportions given in the foregoing Example A, can vary within wide limits,
and in place of sulphuric acid (66 degrees Baumé), stronger acids, such as
monohydrated sulphuric acid, or moderately fuming sulphuric acid, can be used.
According to the conditions under which the processes are carried out,
hydroxyanthraquinone sulpho acids are formed to a greater or less extent. These
sulpho acids can easily be isolated by salting out, and are converted into the
non sulphonated hydroxyanthraquinones by separating the sulpho groups in a
suitable manner.
The anthraquinone sulpho acids can likewise be used in this process, in which
case sulpho groups are partly eliminated during the reaction.
As above mentioned, the process proceeds in a similar manner, if
hydroxyanthraquinones, or hydroxyanthraquinone sulpho acids, are used in place
of anthraquinone or authraquinone sulpho acids.
The researches of my foreign correspondents have shown that coloring matters
of special value are obtained by treating with sulphuric acid in the presence of

page_text: boric acid, or the like, such dihydroxy-, trihydroxy-, or tetrahydroxyanthraquinones,
or sulpho acids thereof, as contain hydroxylic groups in each of the two benzene
nuclei of the anthraquinone molecule. For instance, coloring matters producing
blue shades with the aid of chromium mordants, result, if the following products
are subjected to the above mentioned process, viz.:-anthrarufin, oxychrysazin,
anthraflavinic acid, or the condensation product which is obtainable on condensing
metahydroxybenzoic acid with sulphuric acid, and contains, for the most part,
.anthraflavinic acid or those two trihydroxyanthraquinones which my foreign
correspondents have produced by condensing one molecular proportion of
metahydroxybenzoic acid with one molecular proportion of symmetrical dihydroxy-
benzoic acid, with the aid of sulphuric acid. A dye-stuff which likewise yields
blue shades, when dyed on chrome mordanted material, is obtained on beating
anthrachryson (tetrahydroxyanthraquinone) with sulphuric acid, in the presence of
boric acid, or the like, and the coloring matter thus obtainable chiefly consists of
hexahydroxyanthraquinone.
According to the researches of my foreign correspondents, the sulpho acids of
the above named hydroxyanthraquinones, or the like, can also be used, the sulpho
group being mostly displaced at the temperature at which the reaction takes place,
and in place of starting from the hydroxyanthraquinones, the hydroxybenzoic
acids, dihydroxybenzoic acids, tribydroxybenzoic acids, from which the hydroxy-
authraquinones can be obtained, may be subjected to the above defined process,
oic. heated with sulphuric acid in the presence of boric acid or the like, coloring
matters being likewise thus formed.
The following example is given in order to illustrate one of the methods of
producing a polyoxyanthraquinone dye-stuff from metahydroxybenzoic acid, and
in this example the conversion of the said meta hydroxybenzoic acid into the
condensation product, which chiefly is anthraflavinic acid, and the transformation
of this condensation product into the polyoxyanthraquinone coloring matter, is
.carried out in one operation. The parts are by weight.
DYE-STUFF OBTAINED FROM META HYDROXYBENZOIC ACID WITH THE AID
OF SULPHURIC ACID IN THE PRESENCE OF BORIC ACID.
10 parts of metahydroxybenzoic acid are mixed with 10 parts of boric acid and
200 parts of sulphuric acid (66 degrees Baumé), and the resulting mixture is
heated at from 260 to 280 degrees centigrade, until the inass has assumed a blue
color. After cooling, the mass is poured into water, and the liquid mixture is
heated to boiling. The dye-stuff which is separated is filtered off.
The coloring matter thus obtainable chiefly consists of hexahydroxyanthraquinone
described in the Specification of Letters Patent No. 18729 of 1890. It yields
violet and blue shades, when it is used to dye materials morlanted respectively
with alumina or chromium salts.
The sulphuric acid (66 degrees Baumé) can be replaced by stronger acids, such
as monohydrated sulphuric acid, or moderately fuming sulphuric acid.
The other dye-stuffs are obtained in a manner analogous to that described in the
above example (B).
The meta hydroxybenzoic acid used in Example B can be replaced by the
homologues or analogues thereof, such as meta-hydroxytoluylic acid or the like.
The conversion of the complete di-, tri-, and tetrahydroxyanthraquinones into
dye-stuffs, is effected in a manner analogous to that describel in Example A.
A result of special value is obtained, if anthrachrysou (tetrahydroxyanthra-
quinone) is treated in the aforesaid manner with sulphuric in the presence of boric
acid or the like, for whereas anthrachryson, by treatment with sulphuric anhydride
or fuming sulphuric acid of a high percentage, as described in the Specification
of Letters Patent No. 13677, dated 13th August 1891, is easily converted into th

page_text: hexahydroxyanthraquinone mentioned in the Specification of Letters Patent
No. 18729, dated 19th November 1890, and the same result is obtained on acting
with manganese or analogous oxidising agents on anthrachryson dissolved in
concentrated sulphuric acid (66 degrees Baumé), according to the process described
in the Specification of Letters Patent No. 21717, dated 11th December 1891, the
oxidation of anthrachryson into hexahydroxyanthraquinone, by heating the former
alone with concentrated sulphuric acid, at elevated temperatures (that is to say, by
means of the process according to which alazarin bordeaux, is oxidized into
hexahydroxyanthraquinone, as described in the Specification of Letters Patent
No. 17712, dated 4th November 1890) could not hitherto be effected in a
satisfactory manner, as my foreign correspondents have found that a decomposition
of anthrachryson to a large extent takes place at the high temperature which would
be necessary.
My foreign correspondents have now found that a dye-stuff which, for the most
part, consists of the above named hexahydroxyanthraquinone, is obtained in a very
convenient manner, if anthrachryson is heated with concentrated sulphuric acid at
elevated temperatures, in the presence of boric acid, or analogous substances acting
in the same or a similar manner.
The result obtainable on heating anthrachryson under the same conditions with
concentrated sulphuric acid, without any addition of boric acid or the like, is
destitute of any technical value. This circumstance also proves the advantageous
action of boric acid, or the like, on hydroxyanthraquinones, or derivatives thereof,
when treated with sulphuric acid at elevated temperatures.
The treatment of anthrachryson with sulphuric acid in the presence of boric acid,
or the like, is illustrated by the following example. The parts are by weight.
PRODUCTION OF A DYE-STUFF FROM ANTHRACHRYSON BY MEANS OF
SULPHURIC ACID IN THE PRESENCE OF BORIC ACID.
10 parts of anthrachryson are mixed with 10 parts of crystallised boric acid
and 200 parts of sulphuric acid (66 degrees Baumé). The resulting mixture is
heated at 250 to 270 degrees centigrade, until the mass has assumed an intense
bluish-violet colour, which does not alter on further heating. After cooling, the
mass is poured into water, and the resulting liquid mixture is heated to boiling.
The colouring-matter which is separated filtered off. It chiedy consists of the
above named hexahydroxyanthraquinone, and yields violet and blue shades, when
it is dyed on materials mordanted either with alumina or chromium mordants.
The same result is obtained according to the researches of my foreign
correspondents, if symmetrical dihydroxybenzoic acid (1:3: 5) is used in the
above process. In this case, the conversion of dihydroxybenzoic acid into
anthrachryson, and the oxidation of the latter into hexahydroxyanthraquinone,
can be carried out in a single operation, as is evident from the following example.
TIL
COLOURING-MATTER OBTAINED FROM DIHYDROXYBENZOIC ACID BY MEANS
OF SULPHURIC ACID AND BORIC ACID.
10 parts of dihydroxybenzoic acid are mixed with 200 parts of sulphuric acid
(66 degrees Baumé), and this mixture is heated during some hours at about
120 degrees centigrade. 10 parts of boric acid are then introduced into the
80-formed sulphuric acid solution of anthrachryson, and the oxidation is effected
by heating, as described in the above examples.
The researches of my foreign correspondents have shown that, in place of
sulphuric acid (66 degrees Baumé) used in the above examples, stronger acids can

page_text: be used with the same result, such as monohydrated sulphuric acid, or moderately
fuming sulphuric acid. The temperature can vary within wide limits, and the
boric acid can be replaced by salts of boric acid, or such boron compounds which,
when employed in the presence of sulphuric acid, yield boric acid.
Dated this 16th day of January 1894.
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION.
The Manufacture or Production of Anthraquinone Derivatives.
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 :—
My foreign correspondents have found that not only can nitro and amido
anthraquinones be converted into hydroxyanthraquinones, by heating them with
concentrated sulphuric acid in the presence of boric acid, or similar substances
yielding boric acid, when used together with sulphuric acid, but that anthraquinone
and certain hydroxyanthraquinones derived therefrom are also acted on in the
same manner.
This interesting and technically valuable action proceeds very satisfactorily, for
instance, in the case of anthraquinone, a considerable amount of quinizarin being
first formed, which, by further oxidation, is then transformed into purpurin.
One method of converting anthraquinone into quinizarin is illustrated by the
following example. The parts are by weight.
CONVERSION OF ANTHRAQUINONE INTO QUINIZARIN BY MEANS OF SULPHURIC
ACID IN THE PRESENCE OF BORIC ACID.
10 parts of anthraquinone are mixed with 10 parts of crystallised boric acid and
200 parts of sulphuric acid (66 degrees Baumé), and the mixture is heated. An
energetic, though not violent, action sets in at from 260 to 280 degrees centigrade,
sulphur dioxide being disengaged.
The formation of quinizarin is complete within a comparatively short time, but
the conversion of quinizarin into purpurin necessitates heating during a longer
period. The progress and end of the change may be ascertained by the spectrocopic
examination of test portions diluted with sulphuric acid.
In order to separate the hydroxyanthraquinone, the mass is poured into water.
The separated hydroxy product is filtered off, and, if necessary, is purified by
redissolving it in alkali precipitating with acids, and "gain filtering off.
The proportions given in the foregoing first example can be varied within wide
limits, and in place of sulphuric acid (66 degrees Baumé), stronger acids can be
used, such as monohydrated sulphuric acid, or moderately fuming sulphuric acid.
According to the conditions under which the processes are carried out, hydroxy-
anthraquinone sulphonic acids are also formed to a greater or less extent. These
sulphonic acids can easily be separated by salting out, and are converted into the
non-sulphonated hydroxyanthraquinones by separating the sulphonic groups in a
suitable manner.
The anthraquinone sulphonic acids can also be used in this process, in which case
the sulphonic groups are partly eliminated.
As above mentioned, the action proceeds in a similar manner, if certain
bydroxyanthraquinones, or hydroxyanthraquinone sulphonic acids, are used in place
of anthraquinone or anthraquinone sulphonic acids.

page_text: The researches of my foreign correspondents have shown that coloring matters
of special value are obtained by the action of sulphuric acid in the presence of
horic acid or the like on dihydroxy, trihydroxy, or tetrahydroxy-anthraquinones, or
sulphonic acids thereof, containing hydroxyl groups in each of the two benzene
nuclei of the anthraquinone molecule. For instance, coloring matters producing
blue shades with the aid of chromium mordants, are formed, if the following
products are subjected to the above mentioned process, viz., anthrarufin, oxychrysazin,
anthraflavic acid, or the condensation product obtainable by condensing meta-
hydroxybenzoic acid by means of sulphuric acid, and consisting, for the most part,
of anthraflavic acid, or the two trihydroxyanthraquinones which my foreign
correspondents have produced by condensing a molecular proportion of meta-
hydroxybenzoic acid with a.molecular proportion of symmetrical dihydroxybenzoic
acid, with the aid of sulphuric acid. A dye-stuff which also yields blue shades,
when dyed on chrome mordanted material, is obtained on heating anthrachryson
(tetrahydroxyanthraquinone) with sulphuric acid in the presence of boric acid, or
the like, the coloring matter thus obtainable chiefly consisting of hexahydroxy-
anthraquinone.
According to the researches of my foreign correspondents, the sulphonic acids of
the above-named hydroxyanthraquinones, or the like, can also be used, the sulphonic
group being for the most part displaced at the temperature at which the action
takes place, and instead of starting from the hydroxyanthraquinones, the hydroxy-
benzoic acids, dihydroxybenzoic acids, trihydroxybenzoic acids, from which the
hydroxyanthraquinones can be obtained, may be subjected to the above defined
process, riz., heated with sulphuric acid in the presence of boric acid or the like,
coloring matters being also formed by operating in this manner.
The following example is given in order to illustrate one of the methods of
producing a polyhydroxyanthraquinone dye-stuff from metahydroxybenzoic acid,
this example being one in which the conversion of the said metahydroxybenzoic
acid into the condensation product, chiefly consisting of anthraflavic acid, and the
transformation of this condensation product into the polyhydroxyanthraquinone
coloring matter, is carried out in one operation. The parts are by weight.
DYE-STUFF OBTAINED FROM META HYDROXYBENZOIC ACID WITH THE AID
OF SULPHURIC ACID IN THE PRESENCE OF BORIC ACID.
10 parts of metahydroxybenzoic acid are mixed with 10 parts of boric acid and
200 parts of sulphuric acid (66 degrees Baumé), and the mixture is heated at
from 260 to 280 degrees centigrade, until it has assumed a blue color. When
cool, the mass is poured into water, and the liquid mixture is heated to boiling.
The dye-stuff which separates is then filtered off.
The coloring matter thus obtainable chiefly consists of the hexahydroxyanthra-
quinone described in the Specification of Letters Patent No. 18729 of 1890. It
yields violet and blue shades when it is used to dye materials mordanted with
alumina or chromuim salts respectively.
Other dye-stuffs are obtained in a manner analogous to that described in the
above second example.
In place of the metahydroxybenzoic acid used in the second example, the
homologues or analogues thereof, such as meta hydroxytoluylic acid, or the like,
can be used.
The conversion of di, tri, and tetra hydroxyanthraquinones into dye-stuffs, is
effected in a manner analogous to that described in the first example.
A result of special value is obtained if anthrachryson (tetrahydroxyanthra-
quinone) is acted on in the aforesaid manner with sulphuric acid in the presence of
boric acid or the like, for whereas, on treatment with sulphuric anhydride, or
fuming sulphuric acid of a high percentage, as described in the Specification of
•

page_text: Letters Patent No. 13677, dated 13th August 1891, anthrachryson is easily
converted into the hexahydroxyanthraquinone mentioned in the Specification of
Letters Patent No. 18729, dated 19th November 1890, and the same result is
obtained on acting with manganese dioxide, or analogous oxidising agents, on
anthrachryson dissolved in concentrated sulphuric acid (66 degrees Baumé),
according to the process described in the Specification of Letters Patent No. 21717,
dated 11th December 1891, the oxidation of anthrachryson into hexahydroxyanthra-
quinone, by heating the former with concentrated sulphuric acid alone at elevated
temperatures (that is to say, by means of the process whereby alizarin bordeaux is
oxidised into hexahydroxyanthraquinone, as described in the Specification of
Letters Patent No. 17712, dated 4th November 1890), could not hitherto be
effected in a satisfactory manner, my foreign correspondents having found that a
decomposition of anthracryson takes place to a large extent at the high temperature
necessary to bring about the change.
My foreign correspondents have now found that a dye-stuff which, for the most
part, consists of the above-named hexahydroxyanthraquinone, is obtained in a very
convenient manner, if anthrachryson is heated with concentrated sulphuric acid at
elevated temperatures in the presence of boric acid, or analogous substances acting
in the same or a similar manner.
The treatment of anthrachryson with sulphuric acid in the presence of boric
the like is illustrated by the following example. The parts are by
id
PRODUCTION OF A DYE-STUFF FROM ANTHRACHRYSON BY MEANS OF
SULPHURIC ACID IN THE PRESENCE OF BORIC ACID.
10 parts of anthrachryson are mixed with 10 parts of crystallised boric acid and
200 parts of sulphuric acid (66 degrees Baumé), and the mixture is heated at
from 250 to 270 degrees centigrade, until the mass has assumed an intense bluish-
violet color, which does not alter on further heating. When cool, the mass is.
poured into water, and the liquid mixture is then heated to boiling. The coloring
matter which separates is filtered off. It chiefly consists of the above-named
hexahydroxyanthraquinone, and yields violet and blue shades when it is used to
dye materials mordanted either with alumina or chromium mordants.
The same result is obtained according to the researches of my foreign corre-
spondents, if symmetrical dihydroxybenzoic acid (1:3:5) is used in the above
process. In this case, the conversion of dihydroxybenzoic acid into anthrachryson,
and the oxidation of the latter into hexahydroxyanthraquinone, can be carried out
in a single operation, as is evident from the following example. The parts are by
weight.
FOURTH EXAMPLE.
COLORING MATTER OBTAINED FROM DIHYDROXYBENZOIC ACID BY
OF SULPHURIC ACID AND BORIC ACID.
MEANS
10 parts of dihydroxybenzoic acid are mixed with 200 parts of sulphuric acid
(66 degrees Baumé), and this mixture is heated during several hours at about
120 degrees centigrade. 10 parts of boric acid are then introduced into the
solution of anthrachryson in sulphuric acid which is thus produced, and the
oxidation is effected by heating as described in the abɔve examples.
The researches of my foreign correspondents have shown that in place of
sulphuric acid (66 degrees Baumé) used in the above examples, stronger acids can
be used with the same result, such as monohydrated sulphuric acid, or moderately
fuming sulphuric acid. The temperature can be varied within wide limits, and
salts of boric acid, or boron compounds yielding boric acid when used in the
presence of sulphuric acid, can be substituted for boric acid.
-

page_text: 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 quinizarin and purpurin with the aid of boric acid, or
other boron compounds yielding boric acid when used together with sulphuric acid,
which process consists in heating, at elevated temperatures, anthraquinone or
anthraquinone sulphonic acids with concentrated or monohydrated, or moderately
fuming sulphuric acid, in the presence of boric acid, or the like, then separating
the quinizarin and purpurin which are directly formed, and subsequently treating
in a suitable manner the hydroxyanthraquinone sulphonic acids, if any are produced,
at the same time, in order also to convert them into quinizarin and purpurin.
2. The process for producing anthraquinone dye-stuffs with the aid of boric acid,
or other boron compounds yielding boric acid when used together with_sulphuric
acid, which process consists in heating at elevated temperatures, dihydroxy,
trihydroxy, or tetrahydroxyanthraquinones containing hydroxyl groups in either
benzene nucleus of the anthraquinone molecule, or sulphonic acids of such
polyhydroxyanthraquinones, with concentrated monohydrated or moderately fuming
sulphuric acid in the presence of boric acid or the like.
3. The use, in the process claimed by the foregoing second claim, of anthrarufin,
oxychrysazin, anthraflavic acid, the product consisting mainly of anthraflavic acid
obtainable by condensing metahydroxybenzoic acid with the aid of sulphuric acid,
or the trihydroxyanthraquinones obtainable by condensing molecular proportions
of metahydroxybenzoic acid and symmetrical dihydroxybenzoic acid, with the aid of
sulphuric acid, or anthrachryson or sulphonic acids of these polyhydroxyanthra-
quinones.
4. The production of anthraquinone dye-stuffs with the aid of boric acid or other
boron compounds yielding boric acid when used together with sulphuric acid, which
process consists in heating at elevated temperatures, with concentrated mono-
hydrated or moderately fuming sulphuric acid, in the presence of boric acid or the
like, such monohydroxy, dihydroxy, or trihydroxybenzoic, acids or homologues or
mixtures thereof, as, when condensed with the aid of sulphuric acid, are capable of
yielding anthraquinone derivatives.
Dated this 3rd day of October 1894.
NEWTON & SON,
Agents for the Appiicant..