Improvements in the Production of a Blue Green and a Red Violet Colouring Matter from Alizarine Blue.
Year: 1891

page_text: Date of Application, 24th Jan., 1891
Complete Specification Left, 23rd Oct., 1891-Accepted, 28th Nov., 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE FARBWERKE VORMALS MEISTER LUCIUS
AND BRUNING, of Hoechst a/Main, Germany, Chemical Manufacturers.]
Improvements in the Production of a Blue Green and a Red Violet
Colouring Matter from Alizarine Blue.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the
County of London, Fellow of the Institute of Patent Agents, do hereby declare
the nature of this invention to be as follows:
My foreign correspondents have discovered that by treatment with nitro-sulphuric
acid, there is obtained from alizarine blue a nitro-alizarine blue, which by suitable
reduction agents can be converted into amido alizarine blue.
When these nitro and amido alizarine blues are used for dyeing or printing under
the conditions usually employed for alizarine blue, the first will give blue green
shades and the second red violet shades of great depth.
I. PRODUCTION OF THE NITRO ALIZARINE BLUE.
Alizarine blue is easily nitrated by anhydrous nitro-sulphuric acid, not by
hydrous nitrosulphuric acid which has no action or only an oxidising action on the
alizarine blue.
One part by weight of alizarine blue in fine powder is added at 0° C. to a mixture
of 14 parts of nitric acid of 47° Bé. and 4 parts of sulphuric acid containing
20 per cent. of anhydride and the whole is slowly heated to 20° C. When a sample
precipitated by means of water, washed out and redissolved in sulphuric acid is
found not to give the characteristic spectrum of the alizarine blue, the mass is
poured into an excess of diluted soda solution, cooled by means of ice. The sodium
salt which precipitates, and which is soluble with difficulty, is filtered off and the
free nitro alizarine blue is separated by means of an acid.
A solution of the nitro alizarine blue may be used for dyeing and printing alone
or in admixture with bisulphite.
The nitro alizarine blue is in form of a greenish blue powder and is with difficulty
soluble in the ordinary solvents. From naphtha it can be recrystallized in the form
of fine scales. When heated cautiously it melts and becomes sublimed undergoing
decomposition.
In ammonia the nitro alizarine blue dissolves with green coloring, which becomes
a more pronounced green on addition of alcohol.
By this quality it is easily distinguished from the alizarine blue, which under like
conditions produces a pure blue coloring.
Also the salts of the nitro alizarine blue, such as the calcium, aluminium, chromium,
and iron salts, are green.
The solution in concentrated sulphuric acid extinguishes the green of the spectrum,
but lets the yellow and red pass unabsorbed, in which the alizarine blue shews the
characteristic absorption line.
With acids the nitro alizarine blue forms salts, which can be decomposed by cold
water.
The sulphate has a strong red color.
Reducing agents convert the nitro alizarine blue into amido alizarine blue.
II. PRODUCTION OF THE AMIDO ALIZARINE BLUE.
One nont of nitro alizarine blue is suspended in 50 parts of water, to which are

page_text: heated to 70° or 80° C. until a sample decomposed by an acid, filtered off and
washed, dissolves in ammonia with pure blue coloring. At this point the mass is
acidulated, the amido compound that has formed is filtered off and well washed.
For the glucose may be substituted other alkaline reducing agents such as sulpho-
alkalies or oxydule of tin.
The amido alizarine blue has a dark red blue color and, like the nitro alizarine
blue, it is soluble with great difficulty in the known solvents.
In ammonia it dissolves with pure blue coloring and, unlike the nitro alizarine
blue, it forms blue salts which are soluble with difficulty. The salts that it forms
with acids, also are decomposed by water.
The amido alizarine blue is a coloring matter of extraordinary strength and
furnishes red violet shades twice as deep as those produced by alizarine blue.
It can be used for dyeing and printing by itself and also when dissolved with
bisulphite.
Dated this 24th day of January 1891.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Production of a Blue Green and a Red Violet
Colouring Matter from Alizarine Blue.
I, OLIVER IMRAY of No. 28 Southampton Buildings, Chancery Lane, in the
County of London, Fellow of the Institute of Patent Agents, 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 discovered that by treatment with nitro-sulphuric
acid there is obtained from alizarine blue a nitro alizarine blue, which by suitable
reduction agents can be converted into amido alizarine blue.
When these nitro and amido alizarine blues are used for dyeing or printing under
the conditions usually employed for alizarine blue, the first will give blue green
shades and the second red violet shades of great depth.
I. PRODUCTION OF THE NITRO ALIZARINE BLUE.
Alizarine blue is easily nitrated by anhydrous nitro sulphuric acid, not by
hydrous nitrosulphuric acid which has no action or only an oxidising action on the
alizarine blue.
One part by weight of alizarine blue in fine powder is added at 0° C. to a mixture
of 1 parts of nitric acid of 47° Bé. and 44 parts of sulphuric acid containing
20 per cent. of anhydride and the whole is slowly heated to 20° C. When a sample
precipitated by means of water, washed out and redissolved in sulphuric acid is
found not to give the characteristic spectrum of the alizarine blue, the mass is
poured into an excess of diluted soda solution, cooled by means of ice. The sodium
salt which precipitates, and which is soluble with difficulty, is filtered off and the
free nitro alizarine blue is separated by means of an acid.
A solution of the nitro alizarine blue may be used for dyeing and printing alone
or in admixture with bisulphite.
The nitro alizarine blue is in form of a greenish blue powder and is with difficulty
soluble in the ordinary solvents. From naphtha it can be recrystallized in the form
of fine scales. When heated cautiously it melts and becomes sublimed undergoing
decomposition.
In ammonia the nitro alizarine blue dissolves with green coloring, which becomes
a more pronounced green on addition of alcohol.
By this quality it is easily distinguished from the alizarine blue, which under like
conditions produces a pure blue coloring.

page_text: Also the salts of the nitro alizarine blue, such as the calcium, aluminium, chronium,
and iron salts, are green.
The solution in concentrated sulphuric acid extinguishes the green of the spectrum,
but lets the yellow and red pass unabsorbed, in which the alizarine blue shews the
characteristic absorption line.
With acids the nitro alizarine blue forms salts, which can be decomposed by cold
water.
The sulphate has a strong red color.
Reducing agents convert the nitro alizarine blue into amido alizarine blue.
II. PRODUCTION OF THE AMIDO ALIZARINE BLUE.
One part of nitro alizarine blue is suspended in 50 parts of water, to which are
added 2 parts of sodium lye of 35 per cent. and 8 parts of glucose, and the whole is
heated to 70° or 80° C. until a sample decomposed by an acid, filtered off and
washed, dissolves in ammonia with pure blue coloring. At this point the mass is
acidulated, the amido compound that has formed is filtered off' and well washed.
For the glucose may be substituted other alkaline reducing agents such as sulpho-
alkalies or protoxyde of tin.
The amido alizarine blue has a dark red blue color and, like the nitro alizarine
blue it is soluble with great difficulty in the known solvents.
In ammonia it dissolves with pure blue coloring and, unlike the nitro alizarine
blue it forms blue salts which are soluble with difficulty. The salts that it forms
with acids, also are decomposed by water.
The amido alizarine blue is a coloring matter of extraordinary strength and
furnishes red violet shades twice as deep as those produced by alizarine blue.
It can be used for dyeing and printing by itself and also when dissolved with
bisulphite.
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 production of nitro-alizarine blue by the action of an anhydrous mixture
of nitric and sulphuric acids upon alizarine blue and its conversion into amido-
alizarine-blue by the action on it of alkaline reduction agents such as glucose,
sulpho-alkalies, protoxyde of tin substantially as described.
2. The nitro- and amido-alizarine-blues, produced by the above process.
1001
ABEL & IMRAY,
Agents for the Applicant.