Manufacture of a Black Colouring Matter directly Dyeing Cotton.
Year: 1899

page_text: Manufacture of a Black Colouring Matter directly Dyeing Cotton.
I, CHARLES DENTON ABEL, of Birkbeck Bank Chambers, Southampton Buildings,
in the County of London, Consulting Engineer and Chartered Patent Agent,
do hereby declare the nature of this invention (as communicated to me from
abroad by Actien-Gesellschaft für Anilin-Fabrikation, of Berlin, in the Empire of
Germany, Chemical Manufacturers) to be as follows:-
My foreign correspondents have found that a valuable black dyestuff directly dyeing
cotton and distinguished by its great tinctorial power is obtained by beating with
sulphur and sodium sulphide a mixture of equimolecular proportions of dinitrooxydi-
1
1
and picramic acid.
The invention is illustrated by the following example:
20 kilos. of dinitrooxydiphenylamine are mixed with 14.3 kilos. of picramic acid
and the mixture is introduced at about 100° C. into a melted mixture of 170 kilos. of
sodium sulphide, 60 kilos. of sulphur and 15 kilos. of water.
The mass
is gradually heated up to 145° C. and this temperature is maintained during several
hours. In order to obtain the colouring matter produced in commercial form several
methods may be adopted.
The formation of a dark black colouring matter begins almost at once.
The mass is heated to a somewhat higher temperature (160° to 170° C.) until it is
dry and can be pulverised. Or the mass may be dissolved in water, the aqueous
solution caused to precipitate by means of common salt and the precipitate dried. Or
the dyestuff may be precipitated from the aqueous solution of the mass by means of
an acid, the precipitate thus produced redissolved in an aqueous solution of sodium
sulphide and the solution evaporated to dryness.
The colouring matter obtained in any of these ways dissolves in water forming a
deep blue black solution. It dyes cotton in a bath containing some salt deep violet
khadaa

page_text: In the process above described picric acid may be substituted for picramic acid
without altering the nature of the dyestuff produced.
1000
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Manufacture of a Black Colouring Matter directly Dyeing Cotton.
1, CHARLES DENTON ABEL, of Birkbeck Bank Chambers, Southampton Buildings,
in the County of London, Consulting Engineer and Chartered Patent Agent,
do hereby declare the nature of this invention (as communicated to me from
by Actien-Gesellschaft für Anilin-Fabrikation, of Berlin, in the Empire of Germany,
Cheinical Manufacturers) 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 a valuable black dyestuff directly dye-
ing cotton and distinguished by its great tinctorial power is obtained by heating with
sulphur and sodium sulphide a mixture of equimolecular proportions of dinitro-
oxvdiphenylamine:
aud pieramic acid.
The invention is illustrated by the following example.
20 kilos. of dinitrooxydiphenylamine are mixed with 14.3 kilos. of picramic acid
and the mixture is introduced at about 100° C. into a melted mixture of 170 kilos.
of sodium suphide, 60 kilos. of sulphur and 15 kilos. of water.
The formation of a dark black colouring matter begins almost at once.
The mass
is gradually heated up to 145° C., and this temperature is maintained during several
hours. In order to obtain the colouring matter produced in commercial form several
inethods may be adopted.
The mass is heated to a somewhat higher temperature (160° to 170° C.) until it
is dry and can be pulverised. Or the mass may be dissolved in water, the aqueous
solution caused to precipitate by means of common salt and the precipitate dried.
Or the dyestuff may be precipitated from the aqueous solution of the mass by means
of an acid, the precipitate thus produced re-dissolved in an aqueous solution of sodium.
sulphide and the solution evaporated to dryness.
The colouring matter obtained in any of these ways dissolves in water forming
a deep blue black solution. It dyes cotton in a bath containing some salt deep
violet-black shades.
In the process above described picric acid may be substituted for pieramic acid
without altering the nature of the dyestuff produced.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
clain is-
1. The herein described manufacture of a black colouring matter directly dyeing

page_text: cotton by heating with sulphur and sulphides of alkali metals a mixture of equi-
molecular proportions of dinitrooxydiphenylamine: