Manufacture of Direct Dyeing Azo-colouring Matters.
Year: 1895

page_text: Date of Application, 22nd July, 1895
Complete Specification Left, 30th Mar., 1896-Accepted, 2nd May, 1896
[Communicated from abroad by THE ACTIEN GESELLSCHAFT FÜR ANILIN
FABRIKATION, of Berlin, in the Empire of Germany, Chemical
Manufacturers.]
Manufacture of Direct Dyeing Azo-colouring Matters.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery
Lane, in the County of London, Consulting Engineer and Chartered Patent
Agent, do hereby declare the nature of this invention to be as follows:-
My foreign correspondents have previously communicated to me the production
of azo-colouring matters derived from the tetrazo-compounds of diamido-derivatives
of the following typical formula :
X and Y signifying amido- or hydroxy-groups the positions of which do not
prevent either from themselves or together with the sulpho group the possibility
of introducing two azo-groups.
Further investigations have led my foreign correspondents to the observation that
compounds of the above general formula may gradually be diazotised by the action
of only one molecule of nitrite, being thus transformed into diazo-derivatives,
possessing the following general formula:
Those diazo-derivatives may easily be combined with one molecule of an amine
or of a phenol to form azo-colouring matters which are distinguished by their
tinctorial power and by their fastness to light and to acids.
In order to illustrate the manner in which the production of such azo-colouring
matters may be carried out, the following is given as a typical example, but it is

page_text: not intended to confine the application of this invention either to the diamido-
compound or to the components herein used.
28 kilos. of the diamido-compound of the following constitution formula:
are diazotised by means of 3.5 kilos. of nitrite in presence of hydrochloric acid.
The dark blue solution of the diazo-compound thus obtained is allowed to flow into
a solution of 6.1 kilos. of meta-toluylene-diamine, which is kept alkaline until the
end of the reaction. The combination takes place readily, and the colouring
matter separates as a dark precipitate. After stirring for some time, the mixture
is heated, and the colouring matter is salted out in the usual way. In a dry state,
it forms a dark lustrous powder soluble in water with a darkish blue colour and
dyes unmordanted cotton a fast gray tint which, on using a sufficient quantity of
the colouring matters, is black.
If in the above example the equivalent quantity of B-naphthol be substituted
for the toluylenediamine, a colouring matter is obtained dyeing cotton a bluish
black.
Dated this 22nd day of July 1895.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Manufacture of Direct Dyeing Azo-colouring Matters.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane,
in the County of London, Consulting Engineer and 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 :-
My foreign correspondents have previously communicated to me, as set forth
in my previous Specification No. 7969 of 1895, the production of azo colouring
matters derived from the tetrazo compounds of diamido derivatives of the following
typical formula:

page_text: prevent either from themselves or together with the sulpho group the possibility
of introducing two azo groups.
Further investigations have led my foreign correspondents to the observation
that compounds of the above general formula may gradually be diazotised by the
5 action of only one molecule of nitrite, being thus transformed into diazo derivatives,
possessing the following general formula:
Those diazo derivatives may easily be combined with one molecule of an amine
or of a phenol to form azo colouring matters which are distinguished by their
tinctorial power and by their fastness to light and to acids.
In order to illustrate the manner in which the production of such azo colouring
matters may be carried out, the following is given as a typical example, but it is
not intended to confine the application of this invention either to the diamido
compound or to the components herein used.
28 kilos. of the diamido compound of the following constitution formula :-
are diazotised by means of 3.5 kilos. of nitrite in presence of hydrochloric acid.
The dark blue solution of the diazo compound thus obtained is allowed to flow
into a solution of 6.1 kilos. of meta-toluylene-diamine, which is kept alkaline until
the end of the reaction. The combination takes place readily and the colouring
matter separates as a dark precipitate. After stirring for some time, the mixture
is heated, and the colouring matter is salted out in the usual way.
In a dry state, it forms a dark lustrous powder soluble in water with a darkish
blue colour and dyes unmordanted cotton a fast grey tint which, on using a sufficient
quantity of the colouring matters, is black.
If in the above example, the equivalent quantity of ẞ-naphthol be substituted
for the toluylenediamine, a colouring matter is obtained dyeing cotton a bluish
black.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed, I declare that what
I claim is
1. The herein described manufacture of direct dyeing azo colouring matters by

page_text: combining an amine or a phenol with diazotised compounds of the typical
constitution indicated by the formula :-
ABEL & IMRAY,
Agents for the Applicant.