Production of a Yellow Coloring Matter.
Year: 1890

page_text: Date of Application, 2nd June, 1890
Complete Specification Left, 2nd Mar., 1891-Accepted, 4th Apr., 1891
YIONAL COIFICATION.
[Communicated from abroad by The FARBWERKE VORMALS MEISTER LUCIUS
AND BRUNING, of Hoerchst-am-Main, in the Empire of Germany, Chemical
Manufacturers.]
Production of a Yellow Coloring Matter.
I, OLIVER IMRAY, of No. 28, Southampton Buildings, Chancery Lane, in the
County of London, Fellow of the Institute of Patent Agents, do hereby declare
the nature of this invention to be as follows
:-
This invention relates to the production of a yellow coloring matter by the action
of tetrazodiphenyl upon orthocresotic acid.
For the preparation of the tetrazodiphenyl salt is used sulphate of benzidine in
the form of a paste of from 15 to 20 per cent. About 200 parts by weight of this
paste, corresponding to 282 parts by weight of pure sulphate are mixed in a
suitable vessel with about 350 parts by weight of cold water and to the mixture
are added 295 parts by weight of hydrochloric acid of 30 per cent. The mass is
cooled down by means of ice to +10° C. and at this temperature a solution of 14-07
parts by weight of nitrite of sodium dissolved in from 60 to 80 parts by weight of
cold water is caused to flow in slowly. After having been kept agitated for some
time say from one half to one hour, the benzidine sulphate will have dissolved.
entirely and the diazotising will be completed.
At the same time are dissolved in a vessel of sufficiently large dimensions 31 parts
by weight of orthocresotic acid by means of 19.2 parts by weight of caustic soda
of 100 per cent., and about 1000 parts by weight of cold water. The clear solution
is cooled down to +1° C. by means of ice and the solution of the tetrazodiphenyl
is caused to flow into it under continuous agitation which is kept up for ten hours,
after which time the mixture is heated slowly to 50° C.; it is kept agitated for one
hour more and then the temperature is raised to 60° C. The coloring matter is
precipitated by means of common salt and pressed off hot in a filter press; the
cakes are submitted to hydraulic pressure and afterwards dried at a temperature
between 60° and 70° C.
Dated this 2nd day of June 1890.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Production of a Yellow Coloring Matter.
I, OLIVER IMRAY, of No. 28, Southampton Buildings, Chancery Lane, in the
County of London, Fellow of the Institute of Patent Agents, do hereby declaré
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 :-
This invention relates to the production of a yellow coloring matter by the action
of tetrazodiphenyl upon orthocresotic acid.
For the preparation of the tetrazodiphenyl salt sulphate of benzidine is used in
the form of a paste of from 15 to 20 per cent. About 200 parts by weight of this
paste, corresponding to 28-2 parts by weight of pure sulphate, are mixed in a
suitable vessel with about 350 parts by weight of cold water and to the mixture
are added 295 parts by weight of hydrochloric acid of 30 per cent.
The mass is
cooled down by means of ice to +10° C. and at this temperature a solution of
14.07 parts by weight of nitrite of sodium, dissolved in from 60 to 80 parts by
[Price 4d1

page_text: weight of cold water, is caused to flow in slowly. After having been kept agitated
for some time, say from half an hour to an hour, the benzidine sulphate will have
dissolved entirely and the diazotising will be completed.
At the same time are dissolved in a vessel of sufficiently large dimensions 31 parts
by weight of orthocresotic acid, by means of 19.2 parts by weight of caustic
soda of 100 per cent., and about 1000 parts by weight of cold water. The clear
solution is cooled down to + 1°C: by means of ice and the solution of the
tetrazodiphenyl is caused to flow into it under continuous agitation which is kept
up for ten hours, after which time the mixture is heated slowly to 50° C.; it is
kept agitated for one hour more and then the temperature is raised to 60° C. The
coloring matter is precipitated by means of common salt and pressed off hot in a
filter press the cakes are submitted to hydraulic pressure and afterwards dried at
a temperature between 60° and 70° C.
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 production of a yellow coloring matter by the action of a tetrozodiphenyl
salt upon orthocresotic acid, substantially as described.
2. The yellow coloring matter produced substantially as described.
Dated this 25th day of T1001
ABEL & IMRAY,
Agents for the Applicant.