Manufacture of Direct Dyeing Colouring Matters.
Year: 1895

page_text: Date of Application, 25th Feb., 1895
Complete Specification Left, 16th Nov., 1895-Accepted, 21st Dec.,
1895
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE ACTIEN GESELLSCHAFT FÜR
ANILIN FABRIKATION, of Berlin, in the German Empire, Chemical
Manufacturers.]
Manufacture of Direct Dyeing Colouring Matters.
1, 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:-
By reducing the azo dye deriving from two molecular proportions of para-
nitrodiazobenzol and one molecular proportion of amidonaphtholdisulphonic
acid H by means of sodium sulphide or other reducing agents acting in the same
manner, a product of the following constitution is obtained.
The same product may also be prepared by the action of two molecular
proportions of acetyl-para-phenylenediamine upon one molecular proportion of
amidonaphtholdisulphonic acid H and subsequent saponification.
This product forms in a dry state a black powder of metallic lustre ; it dissolves
in water with an indigo blue colour; the solution in concentrated sulphuric acid is.
of a blue black colour which changes by diluting with water into pure blue, an
excess of water producing a precipitation of the free colour acid.
Now my foreign correspondents have discovered that the above described
product can be transformed into a tetrazo compound, which may be used for the
preparation of valuable tetrazo dye stuffs.
The tetrazo compound of the above described base is moderately soluble in
water with blue black colour and, when it is combined, for instance with toluylen-
diamine, it yields a dyestuff which dyes cotton deep black shades, distinguished by
their fastness against light, acids and alkalies.
For the toluylenediamine can be substituted other dye stuff components (amines,
phenoles, amidophenales, or their sulpho or carbo acids); moreover mixed tetrazo
dyes may be prepared by means of the tetrazo compound above described.
This 95th day of February 1895
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Manufacture of Direct Dyeing 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:-
By reducing the azo dye deriving from two molecular proportions of para-
nitrodiazobenzol and one molecular proportion of amidonaphtholdisulphonic
acid H by means of sodium sulphide or other reducing agents acting in the same
manner, a product of the following constitution is obtained.
The same product may also be prepared by the action of two molecular
proportions of acetyl-para-phenylenediamine upon one molecular proportion of
amidonaphtholdisulphonic acid H and subsequent saponification.
This product forms in a dry state a black powder of metallic lustre ; it dissolves
in water with an indigo blue colour; the solution in concentrated sulphuric acid is
of a blue black colour which changes by diluting with water into pure blue, an
excess of water producing a precipitation of the free colour acid.
Now my foreign correspondents have discovered that the above described
product can be transformed into a tetrazo compound, applicable for the preparation
of valuable tetrazo dye stuffs which in general dye cotton dark shades distinguished
by their fastness against light, acids and alkalies.
The manufacture of these new dyes may be illustrated by the following
example :-
14 parts of the amido compound described above are tetrazotised by means
of 3-5 parts of nitrite of soda and twenty parts hydrochloric acid of 20° Bé.
The tetrazo compound thus obtained is moderately soluble in water with a blue
black colour. Its aqueous solution is poured into a cold solution of 6.1 parts of
toluylenediamine which is kept alkaline by an excess of carbonate of soda.
The formation of the new dyestuff is completed after a short time and the dye
is separated by means of salt, filtered and dried.
The new colouring matter in the dry state forms a black powder with a metallic
lustre. It is moderately soluble in cold water, very readily soluble in hot water
with black violet colour, which on addition of caustic soda lye becomes more blue
black. In alcohol it is practically insoluble.
The solution in concentrated sulphuric acid is greenish blue black. On the
addition of water it at first assumes a violet blue colour, then, by further diluting,
the free colour acid is precipitated in the form of dark flakes. The dye produces
on unmordanted cotton in an alkaline or salt bath black shades of great intensity
and remarkable fastness against light, air and soap.
For the toluylenediamine other dye stuff components, amines, phenoles,
amidophenoles, or their sulpho or carbo acids, may be used. Thus beta naphthol,

page_text: for instance, yields a colouring matter producing blue black shades on cotton.
Moreover mixed tetrazo dyes may be prepared by means of the tetrazo compound
above described; for instance the combination product of the latter tetrazo
compound with molecular proportions of alpha,-naphthol-alpha-sulphonic acid and
toluylenediamine is a colouring matter dyeing black blue 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 direct dyeing azo colouring matters by
combining amines, phenoles, amidophenoles or their sulpho or carbo acids with the
tetrazo compound derived from the product possessing the following constitution-
formula:-
NH,CH, – N =N
-
-
NH, OH
N
=
N – CHẠNH,
SO,H
SO,H