Manufacture of a Black-Brown Dyestuff directly Dyeing Cotton.
Year: 1899

page_text: Date of Application, 1st Apr., 1899
Complete Specification Left, 8th Dec., 1899-Accepted, 13th Jan., 1900
PROVISIONAL SPECIFICATION.
Manufacture of a Black-Brown Dyestuff 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:-
It has heretofore been shewn that a black dyestuff directly dyeing cotton is
produced by heating with sulphur and sulphides of alkalies the dinitrooxydiphenyl:
aminesulphonic acid represented by the following formula:
O₂N-
H₂C
-NH
-OH
NO₂
SO₂H
is melted together with sulphur and sulphides of alkalies, a direct dyeing
colouring matter is likewise obtained. They, have, however, made the unexpected
discovery that the dyestuff thus obtained is not black, but dark brown and differs
also essentially in its chemical and physical properties from the colouring matter
obtained by means of dinitrooxydiphenylaminesulphonic acid.
The fact that the presence of a methyl group in ortho-position to the diphenyl-
amine-imido-group is able to alter to this degree the reaction and the properties
of the product obtained, is very remarkable. An explanation for this influence
exerted by the methyl group can at present the less be given as altogether the
process of the reaction of sulphur and sulphide of alkalies on derivatives of
diphenylamine is not at all cleared up as yet.
The sulpho-acid which is used as starting product for the production of the new
dyestuff is obtained by heating equi-molecular quantities of chlorodinitro-benzene and
amido-cresol-sulphonic acid (Gattermann, Berichte der deutschen Chemischen
Gesellschaft XXVII, 1938) in alcoholic solution in the presence of sodium acetate.
The sodium salt of the sulpho-acid thus formed is obtained in the form of orange
coloured leaflets.
In order to produce from this condensation product the new black-brown dyestuff
25 kilos. of dinitrooxyphenyltolylaminesulphonic acid produced in the manner

page_text: described are introduced into a mixture of 30 kilos. of sulphur and 75 kilos. of sodium"
sulphide after this mixture has been heated up to 110° C. The melt is then heated
at 140-150° until it begins to thicken, the temperature is then raised to 150-160°
and maintained until the melt is reduced to complete dryness. The product thus
obtained is pulverised and can be directly employed for dyeing. It constitutes a
black powder which dissolves in water containing some sodium sulphide with brownish-
gray colour; on addition of acids to this solution a brown precipitate is produced.
Concentrated sulphuric acid dissolves the dyestuff with brown colour. The new
colouring matter dyes cotton black-brown shades.
Dated this 1st day of April 1899.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Manufacture of a Black-Brown Dyestuff 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) and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
It has heretofore been shewn that a black dyestuff directly dyeing cotton is
produced by heating with sulphur and sulphides of alkali metals the dinitrooxy-
diphenylaminesulphonic acid represented by the following formula :
:
colouring matter is likewise obtained.
They have, however made the unexpected discovery that the dyestuff thus obtained
is not black, but dark brown and differs also essentially in its chemical and physical
properties from the colouring matter obtained by means of dinitrooxydiphenylamine-
sulphonic acid.
The fact that the presence of a methyl group in ortho-position to the diphenylamine-
imido-group is able to alter to this degree the reaction and the properties of the
product obtained, is very remarkable. An explanation for this influence exerted by
the methyl group can at present the less be given as altogether the process of the
reaction of sulphur and sulphide of alkalies on derivatives of diphenylamine is not at
all cleared up as yet.

page_text: The sulpho-acid which is used as starting product for the production of the new
dyestuff is obtained by heating equi-molecular quantities of chlorodinitro benzene
and amido-cresol sulphonic acid (Gattermann, Berichte der deutschen Chemischen
Gesellschaft XXVII, 1938) in alcoholic solution in the presence of sodium acetate.
The sodium salt of the sulpho-acid thus formed is obtained in the form of orange
coloured leaflets.
In order to produce from this condensation product the new black-brown dyestuff
25 kilos. of dinitrooxyphenyltolylaininesulphonic acid produced in the manner
described are introduced into a mixture of 30 kilos. of sulphur and 75 kilos. of sodium
sulphide after this mixture has been heated up to 110° C. The melt is then heated
at 140-150° until it begins to thicken, the temperature is then raised to 150°-160°
and maintained until the melt is reduced to complete dryness. The product thus
obtained is pulverised and can be directly employed for dyeing. It constitutes a
black powder which dissolves in water containing some sodium sulphide with brownish
grey colour; on addition of acids to this solution a brown precipitate is produced.
Concentrated sulphuric acid dissolves the dyestuff with brown colour.
The new
colouring matter dyes cotton black-brown shades.
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 herein described manufacture of a black-brown colouring matter directly
dyeing cotton by heating with sulphur and sulphides of alkali metals dinitrophenyl-
para-oxy-tolylamine sulphonic acid, represented by the constitutional formula:-