Improvements in the Manufacture of Colouring Matters Derived from Anthraquinone.
Year: 1891

page_text: Date of Application, 13th Aug., 1891
Complete Specification Left. 13th May. 1892-Accepted. 23rd July. 1892.
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Colouring Matters Derived
from Anthraquinone.
I BENJAMIN WILLCOX of 47 Lincolns Inn Fields in the County of Middlesex
Patent Agent do hereby declare the nature of this invention which has been
communicated to me from abroad by The Farbenfabriken vormals Friedrich Bayer
& Co. of Elberfeld in the Empire of Germany to be as follows:-
This invention relates to a new method of production of hexahydroxyanthra-
quinone first described in the Specification of Letters Patent, No. 18729 dated
19th November 1890.
My foreign correspondents have subjected to the oxidising process described in
the Specification of Letters Patent No 8275 of 5 June 1890 the anthrachryson
which has been produced according to Barth and Sennhoser (Liebig Annalen 164
pages 109 to 115) by heating symmetrical dihydroxy benzoic acid (COOH OH :
OH=1:3: 5), with, or without, sulphuric acid, and which possesses, in accordance
with its formation and its properties, the following formula:-
:
Unlike the latter, which is easily changed into purpurine by oxidising agents, the
anthrachrysone aforesaid is very stable in the oxidation process, but the action of the
sulphuric acid anhydride which my correspondents have found to be an oxidation
process takes place also in the same manner. when the anthrachrysone is employed.
The latter when treated in sulphuric acid solution with a large excess of sulphuric
acid anhydride at ordinary temperature is changed with great readiness into the
sulphuric acid ether of a body. which corresponds to the anthrachrysone in the same
manner as the purpurine corresponds to the purpuroxanthine.
Whilst the anthrachrysone yields with mordants lakes possessing but little
brightness (with alumina mordants faintly red and with chromium mordauts dirty
yellowish brown colours) the new compound shews cyanine-like dyeing properties
as.it produces on wool mordanted with chromium salts blue shades of great purity.
Umina Rd

page_text: Anthrachrysone dissolves in sulphuric acid with a red colour in alkalies with a
yellowish-red colour and in baryta water with a brownish-red colour but the last
named new product is dissolved by sulphuric acid with a blue-red colour the
solution thus obtained shewing a brilliant cinnabar-red fluorescence; by alkalies it
is dissolved with a blue colour whilst with barium salts it yields a blueish black
insoluble lake. This dye stuff is identical with the hexahydroxyanthraquinone
resulting by the oxidation of alizarine bordeaux with sulphuric acid or by the
oxidation of anthraquinone with sulphuric acid anhydride.
:
The reaction takes place in the same manner as that described in the Provisional
Specification of the application for Patent 87250 for other anthraquinone deriva-
tives. The mixture resulting when fuming sulphuric acid acts upon the anthra-
chrysone contains an intermediate product viz. the neutral sulphuric acid ether of
the dye stuff formed. This ether when gradually treated with alkalies and with
boiling diluted mineral acids or when treated directly by heating with sulphuric
acid at 60 degrees Beaumé, is changed into the dye-stuff. The following is given
as an example for the production of the cyanin-like colouring matter from anthra-
chrysone.
10 parts by weight of anthrachrysone are slowly added to 200 parts by weight of
fuming sulphuric acid (containing 80 per cent. of anhydride) at a low temperature
and the mixture is allowed to stand for say about four days and then it is mixed
with 1500 parts by weight of ice water. The precipitate separated represents the
aforesaid intermediate product. It is filtered off, dissolved in about 1500 parts by
weight of water with the addition of a little excess of soda lye, and heated to boiling
(whilst at the same time any acid in excess is added) for about half an hour. The
précipitate is filtered off and washed out. As a little quantity of the cyanine is
always oxidised to quinone although in the presence of sulphurous acid, it is
preferred to add an alkaline sulphite to the alkaline solution.
It is not necessary to employ for this reaction the anthrachryson itself as it may
be produced in this process by introducing the above mentioned.symmetrical
dihydroxy benzoic acid into 20 parts by weight of fuming acid containing
80 per cent. of anhydride. The mixture which is at first colourless soon assumes a
greenish colour, then the production of the anthrachryson is finished and after
further acting for a sufficient time the sulphuric acid ether of the hexahydroxy-
anthraquinone is formed which can be changed into the dye stuff in the manner
hereinbefore described.
Dated this 13th day of August 1891.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Colouring Matters Derived
from Anthraquinone.
I, BENJAMIN WILLCOX of 47 Lincolns Inn Fields in the County of Middlesex,
Patent Agent do hereby declare the nature of this invention (which has been
communicated to me from abroad by The Farbenfabriken vormals Friedrich Bayer
& Co. of Elberfeld in the Empire of Germany) and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention relates to a new method of producing the hexa-hydroxy anthra-
quinone first described in the Specification of Letters Patent No. 18729 dated
November 19th 1890.
My foreign correspondents have subjected to the oxidising process described in
the Specification of Letters Patent No. 8725 dated June 5th 1890 the anthra-
chrysone which was first produced by Barth and Sennhofer (Liebig, Annalen 164,
pages 109 to 115) by heating symmetrical dihydroxy-benzoic acid (COOH: OH:
OH = 13:5) with or without sulphuric acid, and which, judging from the

page_text: manner in which it is formed, and its properties, is a compound of the following
formula:-
:-
When treated in sulphuric acid solution with a large excess of sulphuric
anhydride authrachrysone is readily converted at ordinary temperature into the
sulphuric ether of a compound which bears the same relation to anthrachrysone that
purpurin bears to purpuroxanthin.
Whereas anthrachrysone when treated with mordants yields lakes possessing but
little brightness (with alumina mordants faintly red and with chromium mordants
dirty yellowish-brown colours) the new product resembles cyanin in its dyeing
properties, producing blue shades of great purity on wool mordanted with chromium
salts. Anthrachrysone dissolves in sulphuric acid with a red colour, in alkalies
with a yellowish-red colour and in baryta water with a brownish-red colour. The
new product is dissolved by sulphuric acid with a blueish-red colour, the solution
exhibiting a brilliant cinnabar-red fluorescence. It is dissolved by alkalies with a
blue colour whilst with baryum salts it yields a blucish-black insoluble lake. The
dye-stuff obtained in the aforesaid manner from anthrachrysone is identical with
the hexahydroxyanthraquinone which is described in the Specification of Letters
Patent No. 18729 granted to me and dated November 19th 1890 and which is
obtainable for example by the oxidation of alizarin bordeaux with sulphuric acid or
by the oxidation of anthraquinone with sulphuric anhydride.
The action takes place in the same manner as that described in the Specifica-
tion of the Letters Patent No. 8725 granted to me and dated June 5th 1890 for
other anthraquinone derivatives.
The mixture obtained by the action of fuming sulphuric acid on anthra-
chrysone contains an intermediate product viz. :--the neutral sulphuric ether of
the dye-stuff. This ether is changed into the dye-stuff when gradually treated
with alkalies and with boiling diluted mineral acids or when heated directly
with sulphuric acid at 60 degrees Baumé. The following is given as an example
for the production of the cyanin-like colouring-matter from anthrachrysone.
10 parts, by weight, of anthrachrysone are slowly added to 200 parts, by weight,
of fuming sulphuric acid (containing 80 per cent. of anhydride) at a low temperature
and the mixture is allowed to stand for say about four days after which it is mixed
with 1500 parts, by weight of ice water. The precipitate which separates consists
of the aforesaid intermediate product. It is filtered off, dissolved in about
1500 parts, by weight, of water, with the addition of a slight excess of soda-lye,
and heated to boiling; then sulphuric acid is added in excess and boiling is
continued for about half an hour. The precipitate (which is the dye-stuff) is
filtered off and washed.
It is not necessary to employ anthrachrysoue itself, as it can be produced in the
course of the process, by introducing the herein-before mentioned symmetrical
dihydroxy-benzoic acid into 20 parts, by weight, of fuming acid containing
80 per cent. of anhydride. The mixture which is at first colourless soon assumes a
greenish colour; ultimately when action has gone on for a sufficient length of time
the sulphuric ether of hexahydroxyanthraquinone is formed and can be converted
into the dye-stuff in the manner hereinbefore described.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that

page_text: I am aware of the Specification of Imray's Patent No. 9943 of 1891 and I make
no claim to anything described and claimed therein, but what I claim is :-
1. The production of the sulphuric ether of hexahydroxy anthraquinone by
oxidising either anthrachrysone dissolved in sulphuric acid with a great excess of
sulphuric anhydride or by treating symmetrical dihydroxybenzoic acid with strong
fuming sulphuric acid.
2. The production of hexahydroxyanthraquinone from the sulphuric ether of
hexahydroxyanthraquinone by treating it with alkalies and boiling with diluted acids
or by directly heating it with acid.