The Manufacture of Sulphonated Thionines.
Year: 1890

page_text: Date of Application, 24th Mar.,. 1890
Complete Specification Left, 19th Dec., 1890-Accepted, 21st Feb., 1891
PROVISIONAL SPECIFICATION.
The Manufacture of Sulphonated Thionines.
I, SYDNEY PITT, of Sutton, in the County of Surrey, Gentleman (a communi-
cation to me from abroad by Leopold Cassella and Company, of Frankfort-on-Main,
in the Empire of Germany, Chemnists), do hereby declare the nature of this invention
to be as follows:-
The object of this process is the manufacture of coloring matters of the series
of the thionines, which are to be employed for dyeing animal fibre in an acid
bath.
I. SYMMETRICAL DISULPHOTHIONINES.
a. As point of departure I use the methyl- and ethyl-benzyl-paraphenylenediamine-
sulphonic acids the manufacture of which I describe in the following.
It.
In mixing a strongly acid solution of ethylbenzylanilinsulphonic acid with nitrite
of soda at a temperature not exceeding 20° C., the nitrous acid is absorbed and a
yellow crystalline precipitate separates, which is the nitrosoethylbenzylaniline-
sulphonic acid. This nitrososulphonic acid is difficultly soluble in pure water.
is easily soluble in alkalies or strong acids, with which it forms salts of an intensely
yellow color. In reducing the acid solution with zinc-dust the ethylbenzyl p.
phenylenediamine-sulphonic acid is obtained. By addition of acetate of soda this
latter separates from the neutralized solution in colorless crystals.
It is easily soluble in mineral acids and in alkalies. For the manufacture of
the dye-stuff it is not necessary to isolate the acid; it is sufficient to determine
the quantity contained in the solution by titration with a solution of nitrite
of soda.
In the same manner the methyl derivative is obtained.
b. The introduction of sulphur can be performed by the aid of thiosulphuric acid.
After this process an intermediate product the sulphobenzylmethyl or ethyl-
phenylenediamine thiosulphonic acid is formed.
In the presence of oxidizing means the thiosulphonic acid combines with methyl
or ethylbenzylanilinesulphonic acid and forms the disulphoindamine-thiosulphonate
which gives a dark green solution.
The solution of this body when heated is partly transformed into thionicsulphonic
acid. This transformation is effected with special facility in the presence of chloride
of zinc. The above described reactions can be made all at one time or better in
succession to each other.
For instance-Dissolve 30 kilos. of benzylethylparaphenylenediamine-sulphonic
acid in 300 litres water, neutralise if there is any free mineral acid, mix with a
solution of 26 kilos. thiosulphate of soda to which shortly before at a medium
temperature a solution of 30 kilos. of aluminium sulphate had been added and then
oxydize with 10 kilos. bichromate of potash. The solution which at first is a
deep red soon becomes colorless. Hereupon add a diluted solution of 29 kilos.
benzylethylanilinesulphonic acid and oxydize with 30 kilos. of bichromate of potash
boil for a short time and add during this operation some chloride of zinc. The
dyestuff which has now been formed appears as a dark blueish solution. Filter the
solution and precipitate by means of salt.

page_text: II. UNSYMMETRICAL DISULPHOTHIONINES.
a. By oxydizing the methylensulphobenzyl paraphenylene diaminethiosulphonic
acid in the manner described under 1. with the ethyl-benzyl-aniline sulphonic acid
(or in the reversed way) the methylethyldibenzylthionine disulphonic acid is
obtained which perfectly resembles the diethyl product.
b. By replacing the benzylethylaniline sulphonic acid by 26 kilos. monobenzyl-
anilinesulphonic acid, monomethyl- or ethyl-dibenzylthionine disulphonic acid is
obtained. This coloring matter is similar to the dimethylic derivative producing
however less pure shades.
The dibenzylanilinedisulphonic acid is treated in the way described under I. a.
The dibenzylparaphenylenediaminedisulphonic acid is obtained, which is very easily
soluble. It shows reactions analogous to those of the described acids. Oxydized
together with thiosulphuric acid it is transformed into a thiosulphonic acid. By
oxydizing this together with one equivalent of dimethyl or diethylaniline, methyl-
or ethylaniline, o. toluidine, and heating, unsymmetrical disulpho-acids of thionines
are obtained.
For instance: A solution of 56 kilos. of disulphodibenzył paraphenylenediamine-
thiosulphonic acid is mixed with a solution of 155 kilos. chlorhydrate of dimethyl-
aniline. To this mixture 30 kilos. bichromate of potash are added. The green
solution is heated and during this operation 10 kilos. chloride of zinc are added.
The coloring matter dissolves and the solution is of a deep blue shade. It is then
filtered and precipitated with salt.
III. MONOSULPHOTHIONINES.
These acids are obtained by oxydizing the methyl- or ethylsulphobenzylpara-
phenylenediaminethiosulphonic acids (described under I.) with dimethylaniline,
diethylaniline, monomethylaniline, or orthotoluidine.
The free acids of these coloring matters are difficultly soluble, the salts however
are easily soluble. The shades vary like those of the disulphoacids from blue to
greenish blue.
As an example operate as follows:-
acid
The solutions of 42 kilos. sulphobenzylethylephenylenediaminethiosulpho
and the solution of 185 kilos. of chlorhydrate of diethylaniline are mixed and to
this mixture are added at a temperature of about 10° C. 30 kilos. of bichromate of
potash; the green solution is heated to the boil, then allowed to cool down, and
filtered. The residue is extracted with boiling water containing 10 kilos. of
carbonate of soda, the sodium salt dissolves. The solution is filtered and pre-
cipitated with salt."
Dated this 24th day of March 1890.
CARPMAEL. & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
The Manufacture of Sulphonated Thionines.
1, SYDNEY PITT, of Sutton, in the County of Surrey, Gentleman (a communi-
cation to me from abroad by Leopold Cassella and Company, of Frankfort-on-Main,
in the Empire of Germany, Chemists), 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:-
The object of this invention is the manufacture of colouring matters of the series
of the thionines, which are suitable to be employed for dyeing animal fibre in an
acid bath:
The bodies of this group known up to the present (Lauth's violet, methylene
blue) are not fit for this purpose.

page_text: I. SYMMETRICAL DISULPHOTHIONINES..
a. As point of departure the methyl and ethyl-benzyl-paraphenylenediamine-
sulphonic acids are used; the manufacture of which is described in the following.
On mixing a strongly acid solution of ethylbenzylanilinesulphonic acid with
nitrite of soda at a temperature not exceeding 20° C., the nitrous acid is absorbed
and a yellow crystalline precipitate separates which is the nitrosoethylbenzylaniline-
sulphonic acid. This nitrososulphonic acid is difficultly soluble in pure water. It is
easily soluble in alkalies or strong acids, with which it forms salts of an intensely
yellow colour. On reducing the acid solution with zinc dust the ethylbenzyl p.
phenylenediaminesulphonic acid is obtained. By addition of acetate of soda this
latter is separated from the neutralized solution in colourless crystals.
It is easily soluble in mineral acids and in alkalies. For the manufacture of the
dyestuff it is not necessary to isolate the acid; it is sufficient to determine the
quantity contained in the solution by titration with a solution of nitrite of soda.
In the same manner the methyl derivative is obtained.
b. The introduction of sulphur is performed by the aid of thiosulphuric acid.
After this process an intermediate product the sulphobenzylmethyl or ethyl-
phenylenediamine thiosulphonic acid is formed.
In the presence of oxidizing means the thiosulphonic acid combines with methyl
or ethylbenzylanilinesulphonic acid and forms the disulphoindamine-thiosulphonate
which gives a dark green solution.
The solution of this body when heated is partly transformed into thionicsulphonic
acid. This transformation is effected with special facility in the presence of
chloride of zinc. The above described reactions can be made all at one time or
better in succession to each other.
For instance-Dissolve 30 kilos. of benzylethylparaphenylenediamine-sulphonic
acid in 300 litres water. Neutralise if there is any free mineral acid; mix with a
solution. of 26 kilos. thiosulphate of soda to which shortly before at the ordinary
temperature of the air a solution of 30 kilos. of aluminium sulphate had been added
and then oxydize with 10 kilos. bichromate of potash. The solution which at first
is a deep red soon becomes colourless. Thereupon add a diluted solution of 29 kilos.
benzylethylanilinesulphonic acid and oxydize with 30 kilos. of bichromate of potash,
boil for a short time and add during this operation some chloride of zinc. The dye-
stuff which has now been formed appears as a dark blueish solution. Filter the
solution and precipitate by means of salt. The dyestuff is very easily soluble in
water, more difficultly so in alcohol. It dyes wool a greenish blue of the shade of
the carmine of indigo..
II. UNSYMMETRICAL DISULPHOTHIONINES..
a. By oxydizing the methylsulphobenzylparaphenylene diaminethiosulphonic acid
in the manner described under f. with the ethylbenzylanilinesulphonic acid (or in
the reversed way) the methylethyldibenzylthionine disulphonic acid is obtained
which perfectly resembles the diethyl product.
b. By replacing the benzylethylanilinesulphonic acid by 26 kilos. monobenzyl-
aniline sulphonic acid, monomethyl- or ethyldibenzylthionine disulphonic acid is
obtained. This colouring matter is similar to the dimethylic derivative, producing,
however, less pure shades.
c. The dibenzylaniline disulphonic acid is treated in the way described under I. a.
The dibenzylparaphenylenediaminedisulphonic acid is obtained, which is very easily
soluble. It shows reactions analogous to those of the described acids. Oxydized
together with thiosulphuric acid it is transformed into a thiosulphonic acid. By
oxydizing this together with one equivalent of dimethyl or diethylaniline, methyl-
or ethylaniline, o. toluidine, and heating, unsymmetrical disulpho acids of thionines

page_text: thiosulphonic acid is mixed with a solution of 15.5 kilos. chlorhydrate of dymethyl-
aniline. To this mixture 30 kilos. bichromate of potash are added. The green
solution is heated and during this operation 10 kilos. chloride of zinc are added.
The colouring matter dissolves and the solution is of a deep blue shade. It is then
filtered and precipitated with salt.
These acids are obtained by oxydizing the methyl- or ethylsulphobenzylpara-
phenylenediaminethiosulphonic acids (described under I.) with dimethylaniline,
diethylaniline, monomethylaniline, or orthotoluidine.
The free acids of these colouring matters are difficultly soluble, the salts, however,
are easily soluble. The shades vary like those of the disulpho acids from blue to
greenish bluc.
As an example, operate as follows:
The solutions of 42 kilos. sulphobenzylethylphenylenediaminethiosulpho acid and
18.5 kilos. of chlorhydrate of diethylaniline are mixed and to this mixture are added
at a temperature of about 10° C. 30 kilos. of bichromate of potash, the green
solution is heated to the boil, then allowed to cool down and filtered. The residue
is extracted with boiling water containing 10 kilos. of carbonate of soda, the
sodium salt dissolves. The solution is filtered and precipitated with salt.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is -
1. The process of preparing methyl sulpho benzyl p. phenylene diamine thio-
sulphonic acid or the corresponding ethyl or dibenzyl compound by oxydizing
the methyl-benzyl-, ethylbenzyl-, or dibenzyl p. phenylenediamine sulphonic acid
in presence of thiosulphuric acid.
2. The process of preparing sulphothionines by, oxydizing the thiosulphonic acids
of the first claim together with: a. methylbenzyl- or ethylbenzyl- or dibenzyl- or
monobenzylanilinesulphonic acid, or: b. dimethyl-aniline, diethylaniline, mono-
methylaniline, monoethylaniline, o. toluidine and transforming the indamine-
sulphonic acids into blue dyestuff's.
3. The products resulting from the new processes above described and claimed.
Dated this 18th day of December 1800
CARPMAEL & Co.,
Agents for the Applicant.