Year: 1896

page_text: Date of Application, 5th Aug., 1896-Accepted, 5th Sept., 1896
These unsymmetrical tetrazo compounds (a method for the manufacture of some
compounds of this series is described in the German Patent No. 64398, this
method being less simple and less exact and giving other results) have in certain
respects the character of the known intermediate compounds resulting from the com-
bination of tetrazo compounds with aromatic phenols and amines but differ from
the said known compounds by containing two diazogroups capable of entering into
reaction.
Analogously to the ordinary tetrazo compounds, these unsymmetrical tetrazo
bodies can react in two visible stages with the aromatic amines and phenols and
their derivatives which are capable of entering into combination.
In general even when more than one molecule of the further components is
employed, there is at first formed exclusively a complex intermediate compound of

page_text: The products of the action of two molecules of each of the same or of two
different components of the series of the aromatic amines and phenols or amido-
naphtols, are generally valuable colouring matters. The shades of these lie
between red brown and blueish violet.
The following examples will explain the mode of producing these new
intermediate compounds containing two diazo-groups.
INTERMEDIATE PRODUCT RESULTING FROM 1 MOLECULE OF TETRAZO-
DIPHENYL AND 'I MOLECULE OF DIAZOTISED AMIDONAPHTOLSULFO-
ACID G.
184 kilogrammes of benzidine are 'dissolved on addition of 50 kilogs. of
bydrochloric acid in-water,' and are diazotised as usual with 13-8 kilogs. of nitrite.
Similarly 23.9 kilogs: of amido-naphtol-sulphoacid G (or'an equivalent amount of
the commercial product) are diazotised on addition of 25 kilogs. of hydrochloric
acid. Then the two diazotised substances are mixed, and a solution of -soda is
added to it until a strong alkalinity is produced.
The intermediate compound
separates out in the form of a thick blue crystalline precipitate. The reaction is
completed after a short time; this is indicated by the disappearance of all the
tetrazodiphenyl.
The intermediate compound 'thas produced is nearly insoluble in water.
INTERMEDIATE PRODUCT RESULTING FROM MOLECULE OF TETRAZODITOLYL
AND MOLECULE OF DIAZOTISED AMIDONAPHTOLSULPHOACID G.
-If instead of 18.4 kiloga. of benzidine, an equivalent amount of tolidine, 21.2 kilogs.
be diazotised, as stated in Example 1, soda is added to the solution of the tetrazo
compound-until the reaction is strongly alkaline, and then the diazotised amido-
naphtol-sulpho-acid is allowed to flow slowly in whilst the mixture is kept alkaline,
there is produced-the intermediate compound:

page_text: of amidonaphtol-disulpho-acid H, or equivalent amount of the commercial pro luct,
is diazotised in the usual manner with 6.9 kilogs. of pure nitrite and 25 kilogs. of
hydrochloric acid. Then soda is added to the solution of tetrazodiphenyl until the
reaction is strongly alkaline, and the diazotised amido-naphtol-disulpho-acid is.
caused to flow slowly in whilst the mixture is kept alkaline.
The intermediate compound thus produced :-
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 intermediate compounds which contain two diazo-groups.
capable of entering into combination, by the action of 1 molecule of a tetrazo
compound upon 1 molecule of a diazotised amido naphtol or of a derivative of
the same.
2. The use of the intermediate compounds produced according to Claim 1 for
the production of secondary intermediate compounds and colouring matters, by the
further combination of the same with aromatic oxyamido, amido-oxy, and diamido.
compounds.
BREWER & SON,
London and Leeds, Agents for the Applicant.