Manufacture of Thionine Colouring Matters Dyeing on Mordants.
Year: 1893

page_text: Date of Application, 16th Mar., 1893
Complete Specification Left, 16th Dec., 1893-Accepted, 20th Jan., 1894
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE FARBWERKE vormals MEISTER LUCIUS
AND BRUNING, of Hoechst a Main, in the Empire of Germany, Manu-
facturers.]
Manufacture of Thionine Colouring Matters Dyeing on Mordants.
I, OLIVER IMRAY, of No. 28, Southampton Buildings, Chancery Lane, in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention to be as follows:-
By the German Patent 45839 and a paper by Bernthsen (Annalen 251 p 1 and f)
it has been made publicly known that in the process for producing methylene-blue
described in the German Patent 38573 there are formed thio-sulphonic acids of
para-diamines, which, by suitable reduction, can be converted into the mercaptanes
and disulphides of these bases.
These compounds can be converted by oxidation with monamines, having the
para-position unoccupied, into indamines, which latter, under suitable treatment,
easily transform into the thionines (especially the methylene blue). In this
operation there are employed without exception acid oxidising agents (especially
chromic acid) and in working according to this process it was not possible to bring
forth the substitution of the monamines by poly-valent phenols or oxy-acids.
My foreign correspondents have discovered that the mercaptanes and disulphides
of paradiamines and also the bodies which easily transform into the same, such as
for example the thio-sulphonic acids, combine with gallic acid and analogous bodies
to form thionine colouring matters dyeing on mordants when they are oxidised in
alkaline solution conjointly with these bodies. When the mercaptane of the amido
dimethylaniline, for example, is dissolved in an excess of alkali-lye and admixed
with the molecular quantity of gallic acid, the liquid, similar to an indigo-vat,
assumes on the surface a blue violet colour, and the oxidation can be completed by
blowing in air.
When the disulphide is employed, this must be suspended in the liquid in the
finest possible form, which is arrived at by dissolving it in acid and precipitating
by means of an excess of alkali.
Thiosulphonic acids heated with alkali-lye easily split off into disulphide and
sulphurous acid and as this acid has no influence whatever upon the alkaline
oxidation, the above acids may be used with advantage.
EXAMPLE 2.
2.5 parts by weight of amido dimethylaniline-thio-sulphonic acid and 17 parts
by weight of gallic acid are dissolved in 40 parts by weight of water and heated
to from 60° to 80° C., 4 parts by weight of sodium hydrate are added in the
form of a lye and while being kept at the above temperature air is blown into the
mixture until the termination of the formation of colouring matter.

page_text: In both examples the colouring matter is precipitated by means of common salt;
the sodium salt thus obtained is decomposed by means of acetic acid, and the acid
colouring matter which dissolves with difficulty is brought into the form of a
paste.
The paste forms small bronze coloured crystals easily soluble in diluted hydro-
chloric acid and in diluted alkalies.
For the gallic acid may be substituted its ethers gallaminic acid, tannin or raw
materials containing tannin.
The colouring matters obtained in this way produce on chrome mordants shades
ranging from red-violet to blue according to the nature of the diamine; these
shades are prominent as regards fastness to soap and fulling.
Dated this 16th day of March 1893.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE
SPECIFICATION.
Manufacture of Thionine Colouring Matters Dyeing on Mordants.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the
County of London, Chartered 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 :-.
By the German Patent 45839 and a paper by Bernthsen (Annalen 251 p 1 and f)
it has been made publicly known that in the process for producing methylene-blue
described in the German Patent 38573 there are formed thio-sulphonic acids of
para-diamines, which, by suitable reduction, can be converted into the mercaptanes
and disulphides of these bases.
These compounds can be converted by oxidation with monamines, having the
para-position unoccupied, into indamines, which latter, under suitable treatment
easily transform into the thionines (especially the methylene blue). In this
operation there are employed without exception acid oxidising agents (especially
chromic acid) and in working according to this process it was not possible to bring
forth the substitution of the monamines by poly-valent phenols or oxy-acids.
My foreign correspondents have discovered that the mercaptanes and disulphides
of para-diamines and also the bodies which easily transform into the same, such as
for example the thio sulphonic acids, combine with gallic acid and analogous bodies
to form thionine colouring matters dyeing on mordants when they are oxidised in
alkaline solution conjointly with these bodies. When the mercaptane of the amido
dimethyl-aniline, for example, is dissolved in an excess of alkali-lye and admixed
with the molecular quantity of gallic acid, the liquid, similar to an indigo-vat,
assumes on the surface a blue violet colour, and the oxidation can be completed by
blowing in air.
When the disulphide is employed, this must be suspended in the liquid in the
finest possible form, which is arrived at by dissolving it in acid and precipitating by
means of an excess of alkali.
Thiosulphonic acids heated with alkali-lye easily split off into disulphide and
sulphurous acid and as this acid has no influence whatever upon the alkaline
oxidation, the above acids may be used with advantage.

page_text: EXAMPLE 2.
2.5 parts by weight of amido dimethylaniline thio sulphonic acid and 1.7 parts
by weight of gallic acid are dissolved in 40 parts by weight of water and heated to
from 60° to 80° C., 4 parts by weight of sodium hydrate are added in the form of a
lye and while being kept at the above temperature air is blown into the mixture
until the termination of the formation of colouring matter.
In both examples the colouring matter is precipitated by means of common salt,
the sodium salt thus obtained is decomposed by means of acetic acid and the acid
colouring matter which dissolves with difficulty is brought into the form of a
paste.
The paste forms small bronze coloured crystals easily soluble in diluted hydro-
chloric acid and in diluted alkalies.
For the gallic acid may be substituted its ethers gallaminic acid, tannin or raw
materials containing tannin.
The colouring matters obtained in this way produce on chrome mordants shades
ranging from red violet to blue according to the nature of the diamine; these shades
are prominent as regards fastness to soap and fulling.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:―
1. The manufacture of thionine colouring matters by oxidising gallic acid, gallic
methyl or ethyl-ethers, gallaminic acid, tannin or tannin extracts in alkaline
solution with the thio sulphonic acids, mercaptanes or disulphides, produced as
described in the German Patent 45839 from the following diamines: paraphenylene
diamine, dimethyl-, diethyl-, mono-ethyl paraphenylene diamines, monoethyl-para-
toluylene diamine, substantially as described.
2. The thionine colouring matters manufactured as above set forth.
Dated this 9th day of December 1893
ABEL & IMRAY,
Agents for the Applicant.