Manufacture of a New Amido-base and New Direct Dyeing Polyazo-dyestuffs therefrom.
Year: 1897

page_text: Date of Application, 25th Aug., 1897.
Complete Specification Left, 26th May, 1898-Accepted, 2nd July, 1898
PROVISIONAL SPECIFICATION.
Manufacture of a New Amido-base and New Direct Dyeing
Polyazo-dyestuffs therefrom.
I, OLIVER IMRAY, of No. 28, Southampton Buildings, in the County of London,
Chartered Patent Agent, do hereby declare the nature of this invention (which
has been communicated to me from abroad by Hans Schneider, of Charitéstrasse
No. 3, Berlin, Germany) to be as follows:-
By the combination of 2 molecules of diazotised para-nitranaline with 1 molecule
of resorcinol in an alkali carbonate or caustic alkali solution and the reduction of
the dinitrodiphenyldisazoresorcinol thus formed, a base is obtained which is of great
technical value for the manufacture of direct dyeing azo dyestuffs.
1.) A diazosolution made from 28 kilos. of nitraniline and diluted to 1800 litres,
is run in a thin jet into a solution of 11 kilos. of resorcinol and 43 kilos. of soda-ash
in 2000 litres of water, at a temperature of about 10° C.
The disazobody separates out at once as a fine precipitate; after stirring for
half an hour the temperature is slowly raised to 80 to 90° C. and the substance
filtered off. The dinitrodiphenyldisazoresorcinol thus formed is reduced without
being dried.
It is stirred with water (the volume being about 800 litres) to a thin
paste, heated to 50° C., and then while stirring well 250 litres of a solution of
crystallised sodium sulphide of 42% are added. The reduction begins at once,
the temperature gradually rising spontaneously and being kept at 65 to 70° C. till
a clear solution is obtained. The solution is diluted to three times its volume and
mixed with 90 kilos. of sal-ammoniac dissolved in a little water, thus causing the
new base to separate; this is then well washed on the filter, pressed and dried.
The diamidodiphenyldisazoresorcinol forms a brilliant powder of metallic lustre,
sparingly soluble in water, but easily in dilute hydrochloric acid and is precipitated
from this solution by strong hydrochloric acid as the hydrochloride; it is also
soluble in caustic alkalies.
The base may be diazotised like benzidine and combined in the usual way as tetrazo-
compound with 2 molecules of a suitable substance to produce polyazo-dyestuffs.
These dyestuffs possess great affinity for the vegetable fibre, and are very fast to
soap and light. The easily soluble tetrazo compound of p-diamido-diphenyl-
disazoresorcinol reacts with the greatest readiness; it easily and completely com-
bines with 2 and also with 1 molecule of the usual azo-dyestuff components,
forming in the latter case valuable intermediate products.
The combinations may be carried out in an acetic acid as well as in an alkaline
solution. In contrast with the colours obtained with diphenyl-bases in an acid

page_text: 2.) The tetrazo-solution obtained as above is run into a sufficiently alkaline (with
sodium carbonate) solution of 6-4 kilos. of amidonaphtholsulphonic acid H. The
dyestuff partially separates; after standing some time it is dissolved by heating and
salted out. It dyes unmordanted cotton beautifully greenish-blue.
3.) The tetrazo-solution obtained from 3-5 kilos. p-diamidodiphenyldisazoresorcinol
is combined with 24 kilos. amidonaphtholsulphonic acid G. in a weak acetic acid
solution. A black insoluble intermediate product at once separates; this is soon
afterwards further combined with 3.2 kilos. of amidonaphtholdisulphonic acid H.
The dyestuff dyes unmordanted cotton beautifully blue-black.
The following table of some dyestuffs obtained in this way gives an idea of the
shades belonging to this new class of dyestuffs.
The
"rb" =
abbreviation used here for
resorcinol-base :-
p-diamidodiphenyldisazoresorcinol is

page_text: 1 mol. rb..
/a-naphthylamine-amidonaphtholdisulphonic acid H
amidonaphtholdisulphonic acid H
Manufacture of a New Amido-base and New Direct Dyeing
Polyazo-dyestuffs therefrom.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, (but formerly of No. 28,
Southampton Buildings), Chancery Lane, in the County of London, Chartered
Patent Agent, do hereby declare the nature of this invention (which has been
communicated to me from abroad by Hans Schneider, of Charitéstrasse No. 3,
Berlin, Germany) and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
By the combination of 2 molecules of diazotised para-nitraniline with 1 molecule
of resorcinol in an alkali carbonate or caustic alkali solution and the reduction of
the dinitrodiphenyl-disazoresorcinol thus formed, a base is obtained which is of
great technical value for the manufacture of direct dyeing azo-dyestuffs.
1.) Example. A diazosolution made from 28 kilos. of nitraniline and diluted to
1800 litres, is run in a thin jet into a solution of 11 kilos. of resorcinol and 43
kilos of calcined soda in 2,000 litres of water, at a tenperature of about 10° C.
The disazobody separates out at once as a fine precipitate; after stirring for half
an hour the temperature is slowly raised to 80 to 90° C. and the substance filtered
off. The dinitrodiphenyl-disazoresorcinol thus formed is reduced without being
dried. It is stirred with water (the volume being about 800 litres) to a thin paste,
heated to 50° C., and then while stirring well 250 litres of a solution of crystallised
sodium sulphide of 42% are added. The reduction begins at once, the temperature
gradually rising spontaneously and being kept at 65 to 70° C. till a clear solution
is obtained. The solution is diluted to 3 times its volume and mixed with 90 kilos.
of sal-ammoniac dissolved in a little water, thus causing the new base to separate ;
this is then well washed on the filter, pressed and dried.
The diamidodiphenyldisazoresorcinol forms brilliant powder of metallic
lustre, sparingly soluble in water, but easily in dilute hydrochloric acid and is
precipitated from this solution by strong hydrochloric acid as the hydrochloride; it
is also soluble in caustic alkalies.
ib
The base may be diazotised like benzidine and combined in the usual way as
tet razo-compound with two molecules of a suitable substance to produce
polyazodyestuffs. These dyestuffs possess great affinity for the vegetable fibre,
and are very fast to soap and light. The easily soluble tetrazo compound of
p.-diamido-diphenyldisazoresorcinol reacts with the greatest readiness; it easily and
completely combines with two and also with one molecule of the usual
azo-dyestuff components in an acid solution forming in the latter case valuable.
intermediate products.
The combinations may be carried out in an acetic acid as well as in an alkaline
solution. In contrast with the colours obtained with diphenyl-bases in an acid
solution, which are redder than those obtained in an alkaline solution, the colours

page_text: obtained from the resorcinol-base in an acid solution are of a greener hue than
those obtained in an alkaline solution.
By employing naphthol-and-amido-naphtholsulphonic acids, dyestuffs of great
tinctorial power mostly shades of blue to blue-black, may be obtained, which in
many cases are characterized by a prominent greenish tint.
The best way to obtain intermediate products is in an acid solution, as the tetrazo-
compound as well as the intermediate products are very unstable in an alkaline
solution. The tetrazo-compound turns at once blue in an alkaline solution, and
there separates first a dark blue and finally a black precipitate of dyestuff.
If a component be present in sufficient quantity, the tetrazo-compound reacts
exclusively therewith forming a dyestuff.
The dyestuffs obtained from amido-naphtholsulphonic acid in an alkaline solution
are further diazotisable both separately and on the fibre.
1.) 3.5 kilos. of p-diamidodiphenyldisazoresorcinol are dissolved with 4 molecular 1
proportions of hydrochloric acid and converted by diazotisation in the cold at 5 to
10° C. into the easily soluble orange red-brown tetrazo-compound. The latter
is run into a sufficiently alkaline (with sodium carbonate) solution of 4.8 kilos of
amidonaphtholsulphonic acid G. A blackish-violet precipitate of dyestuff is at once
formed which, after standing some time and having been gently warmed with some 2
salt solution, is filtered off. It dyes unmordanted cotton black.
2.) The tetrazo solution obtained as above is run into a sufficiently alkaline (with
sodium carbonate) solution of 6.4 kilos, of amidonaphtholdisulphonic acid H. The
dyestuff partially separates after standing some time it is dissolved by heating and 2
salted out. It dyes unmordanted cotton beautifully greenish-blue.
:
3.) The tetrazo-solution obtained from 3.5 kilos.p-diamidodiphenyldisazoresorcinol
is combined with 2.4 kilos. amidonaphthol sulphonic acid G. in a weak acetic acid
solution. A black insoluble intermediate product at once separates; this is soon
afterwards further combined with 3.2 kilos. of amidonaphtholdisulphonic acid H.
The dyestuff dyes unmordanted cotton beautifully blue-black.
The following table of some dyestuffs obtained in this way gives an idea of the
shades belonging to this new class of dyestuffs.
The abbreviation used here for p-diamidodiphenyldisazoresorcinol is "rb"
resorcinol-base :-

page_text: 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 new base (diamidodiphenyldisazoresor-
cinol) by combining 2 molecules of diazotised p-nitraniline with 1 molecule of
resorcinol in alkaline solution and reducing the dinitrodiphenyldisazoresorcinol
thus obtained.
2. The herein described manufacture of direct dyeing polyazodyestuffs by the
combination of 1 molecule of the tetrazo-compound of p-diamidodiphenyldisazoresor-
cinol, referred to in Claim 1, in an alkaline, neutral or weak acid solution with two
equal or different molecules of an amine, phenol, amidophenol, their sulphonic or
carboxylic acids.
Q The drostuffé manufactured as above set forth.