The Manufacture and Production of Blue Colouring Matters or Dyestuffs.
Year: 1890

page_text: Date of Application, 27th Sept., 1890
Complete Specification Left, 18th June, 1891-Accepted, 18th July, 1891
PROVISIONAL SPECIFICATION.
The Manufacture and Production of Blue Colouring Matters or
Dyestuffs.
I, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of Middlesex
Patent Agent do hereby declare the nature of this invention which has been
communicated to me from abroad by the Farbenfabriken vormals Friedrich Bayer
and Company of Elberfeld in the Empire of Germany to be as follows:-
:-
It is known that the colouring matter called "New Blue" (Neublau) in the
trade and produced by the action of nitroso dialkyl aniline upon beta-naphthol, can
be converted, by treatment of its watery solution with the secondary amines of the
fatty series and subsequent oxidation into new colouring matters or dyestuffs which
are remarkable for the clearness of their colour and their resistance to alkalies and
which differ essentially from the original material.
When the primary bases of the fatty series or ammonia have been substituted for.
the secondary bases of the fatty series such as dimethyl-amine or diethyl-amine no
useful effect has heretofore been produced.
My foreign correspondents have now discovered that the product commercially
known as "New blue R" being the true oxazine obtained from nitroso dialkyl-
aniline and beta-naphthol combines with ammonia when treated under certain
conditions to form a new dyestuff which differs from the original material by its
essentially more green-blue shade and its essentially greater fastness to alkalies.
This change takes place immediately when the ammonia is allowed to react upon
the "New blue R" in an alcoholic solution.
""
The operation may be conducted according to this invention as follows the parts
being by weight. 25 parts of "New blue R are stirred with alcohol to form a
thin paste and then mixed slowly (whilst at the same cooling) with 7 parts of
a 20 per cent. alcoholic solution of ammonia. The materials are well stirred, allowed
to stand for a few hours and when all the free ammonia has escaped from this.
alcoholic solution oxidation is effected which may be done by introducing a current
of air until the colour of the solution ceases to increase in intensity. The materials.
are then mixed with hot water and the alcohol being evaporated or distilled off,
acetic or hydrochloric acid is added and the colouring matter may then be salted.
out with chloride of zinc.
According to another method a current of air or oxygen which has been taken
through a concentrated solution of ammonia is introduced into an alcoholic solution
of "New blue" until the requisite quantity of ammonia has been taken up. In this
case subsequent oxidation is not necessary.
Dated thie 27th dox of Santamber 1800.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.
COMPLETE SPECIFICATION.
The Manufacture and Production of Blue Colouring Matters or
Dyestuffs.
I BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of Middlesex
Patent Agent do hereby declare the nature of this invention which has been
communicated to me from abroad by Farbenfabriken vorm. F. Bayer & Co. of
Elberfeld Germany and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
It is known that the colouring matters called "New Blue" (in Germany
ID 1

page_text: « Neublau ") by the trade and produced by the action of nitroso-dimethyl- or diethyl-
aniline upon beta-naphthol can be changed by treatment of their watery solutions
with secondary amines of the fatty series and subsequent oxidation into new
colouring matters or dyestuffs which are distinguished for the clearness of their
colours and their fastness when exposed to the action of alkalies and which differ
essentially from the original product.
My foreign correspondents have now discovered that the product known in trade
as "New blue R" being the ozazine obtained from nitroso-dimethyl- or nitroso-
diethyl-aniline and beta-naphthol, yields when treated under certain conditions
with ammonia a new dyestuff which differs from the original product by its essentially
more greenish-blue shade and its much greater fastness in presence of alkalies.
This change takes place instantly when ammonia is allowed to act upon the
"New blue R" in an alcoholic solution.
The operation may be performed according to this invention as follows, the parts
being by weight. 25 parts of, "New blue R" are mixed with alcohol to form a
thin paste and then, whilst cooling, 7 parts of an alcoholic solution of ammonia
containing 20 per cent. of the latter are slowly added. This mixture after being
thoroughly stirred is allowed to stand for a few hours and after the whole of the
free ammonia has disappeared oxidation is effected most practically by passing a
current of air through the alcoholic solution until the colour of the latter ceases to
increase in intensity. The liquid thus obtained is then mixed with hot water and
after the alcohol has been distilled off acetic or hydrochloric acid is added and the
colouring matter may then be salted out by chloride of zinc.
An alternative method consists in passing a current of air at first through a
concentrated solution of ammonia and then through an alcoholic solution of
"New blue" until the requisite quantity of ammonia has been taken up. In this
case subsequent oxidation is not necessary and the dye stuff formed may be directly
salted out after the alcohol has been distilled off.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :
First The process for the manufacture of new blue (of a greenish tinge) fast
colouring matters by the action of ammonia and oxidising agents upon the so called
"New blue R" of commerce.
Second As new articles of manufacture the new dye-stuffs derivable from
nitroso-dimethyl- or nitroso-diethyl-aniline and beta-naphthol such as are produced
by the process herein before described and claimed.
Dated the 18th day of June 1891
J. H. JOHNSON & Co.,
Agents.