The Manufacture and Production of a New Blue Basic Dyestuff.
Year: 1890

page_text: Date of Application, 22nd Oct., 1890
Complete Specification Left, 30th June, 1891-Accepted, 1st Aug., 1891
PROVISIONAL SPECIFICATION.
The Manufacture and Production of a New Blue Basic Dyestuff.
I JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this invention (which has been communi-
cated to me from abroad by The Badische Anilin and Soda Fabrik of Ludwigshafen
on the Rhine in the Empire of Germany) to be as follows:-
By treating meta-toluylene-diamine with nitroso-dimethyl-aniline in aqueous
solution at temperatures not exceeding one hundred degrees Centigrade Witt
obtained an unstable blue dyestuff which he called " toluylene-blue" and which
belongs to the class of the so called indamines (see the journal of the Chemical
Society of the year 1879 Vol. 35 page 356; also Berichte der Deutschen Chemischen
Gesellschaft of the same year Vol. 12 page 931). Witt also examined the action
of the isomeric toluylene-diamines on nitroso-dimethyl-aniline but obtained no
dyestuffs possessing technical value.
Now the present invention is based upon the discovery that by melting together
nitroso-dimethyl-aniline-hydrochlorate and para-phenylene diamine under suitable
conditions as for instance at a temperature of or exceeding one hundred and twenty
degrees Centigrade a valuable, new basic blue dyestuff can be obtained which does
not belong to the class of indamines but resembles rather the indulines. This
dyestuff imparts beautiful deep blue shades to cotton mordanted with tannin which
are characterized by a high degree of fastness to light and soap.
As a convenient means of illustrating the nature of the invention I give by way
of example directions for the production of the new dyestuff but I would premise
that I do not bind myself to the details of these directions as they can be varied in
many ways. It is for instance possible to conduct the operation of melting with or
without the addition of benzoic acid which is not essential but its use enables this
operation to be carried on at a lower temperature and so to obtain a product dyeing
a purer blue colour as if the temperature of the melt be kept higher (at say about
one hundred and seventy degrees Centigrade) then a product dyeing a greyer
shade of blue is obtained. Again the shade also depends upon the proportion of
para-phenylene-diamine used; if for instance, twice the quantity hereinafter
described be taken the dyestuff obtained gives shades of a more purely blue colour.
In the following example the parts are by weight.
Mix about ten parts of para-phenylene-diamine with about one part of benzoic
acid and stir the mixture continuously in a vessel fitted in an oil bath, heat the oil-
bath till the mixture attains the temperature of about one hundred and twenty
degrees Centigrade and then add gradually, at this temperature, during about one hour,
in small portions at a time, about six parts of nitroso-dimethyl-aniline-hydrochlorate
mixed with about three parts of water. Regulate the temperature of the oil bath
so that the temperature of the melt gradually rises, during this time, to about one
hundred and thirty degrees Centigrade and maintain this temperature for about
three or four hours or until no increase in the quantity of dyestuff' formed can be
observed.
Next, extract the melt twice with a hot solution of caustic soda having a
temperature of say eighty to ninety degrees Centigrade. To make this solution
take each time about five parts of soda lye (containing about thirty five per cent.
Under the
of sodium hydrate Na OH) and about three hundred parts of water.
action of the caustic soda the colouring matter, in the form of its base, is freed and
separates out at first as a soft pitch like mass which however solidifies when cold.
Wash with water and then dissolve in the requisite quantity of dilute hydrochloric

page_text: acid (containing about five per cent. of real hydrochloric acid H Cl) filter and
evaporate the solution of the hydrochlorate thus obtained to dryness.
The new dyestuff thus obtained in its commercial form of hydrochloric acid salt
is readily soluble in water yielding a bluish violet solution; it is also soluble in
concentrated sulphuric acid giving a solution of similar colour. In the form of free
base the colouring matter is soluble in alcohol; giving a violet solution but is
practically insoluble in ether.
Datod this 22nd day of October 1890
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, Agents.
COMPLETE SPECIFICATION.
The Manufacture and Production of a New Blue Basic Dyestuff.
I JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of
Middlesex, Gentleman, do hereby declare the nature of this invention which has
been communicated to me from abroad by the Badische Anilin and Soda Fabrik of
Ludwigshafen on Rhine in the Empire of Germany and in what manner the same
is to be performed to be particularly described and ascertained in and by the
following statement :-
By treating meta-toluylene-diamine with nitroso-di-methyl-aniline in aqueous
solution at temperatures not exceeding one hundred degrees Centigrade. Witt
obtained an unstable blue dyestuff which he called "toluylene-blue" and which
belongs to the class of the so called indamines (see journal of the Chemical Society
for the year 1879 Vol. 35, page 356, also Berichte der Deutschen Chemischen
Gesellschaft of the same year Vol. 12 page 931). Witt also examined the action of
the isomeric toluylene diamines on nitroso-dimethyl-aniline but obtained no
dyestuff's possessing technical value.
Now the present invention is based upon the discovery that by melting together
nitroso-dimethyl-aniline-hydrochlorate and para-phenylene-diamine under suitable
conditions, as for instance at a temperature of, or exceeding, one hundred and
twenty degrees Centigrade, a valuable new basic blue dyestuff can be obtained
which does not belong to the class of indamines, but resembles rather the indulines.
This dyestuff imparts beautiful deep blue shades to cotton mordanted with tannin,
which are characterized by a high degree of fastness to light and soap.
As aforesaid the new dyestuff is obtained by melting together nitroso-dimethyl-
aniline-hydrochlorate and para-phenylene-diamine.
The conditions of the process can be varied in several respects and the nature of
the product shews corresponding differences. If the process be conducted at as
low a temperature as possible (say at about one hundred and twenty to one
hundred and thirty degrees Centigrade) purer shades of blue are obtained than if
the temperature of the melt be raised to a higher degree. For instance the.
product obtained at about one hundred and seventy degrees Centigrade yields a
greyish shade of blue.
The addition of a suitable substance of low melting point such as benzoic acid to
the melt renders it possible to carry on this part of the operation at a lower
temperature and so to obtain purer shades of blue.
The proportion of para-phenylene-diamine used also affects the shade of colour
given by the product:-Thus with twenty parts by weight of this diamine and six
parts of the nitroso-di-methylaniline salt a purer blue shade is obtained than with
ten parts of the diamine to six of the nitroso compound.
I give the following examples to illustrate the nature of the invention and the
manner in which it can be carried into practical effect, the parts are by weight.
Example 1. Mix about ten parts of para-phenylene-diamine with about one part
of benzoic acid and stir the mixture continuously in a vessel fitted in an oil bath,
heat the oil bath till the mixture attains the temperature of about one hundred and
1

page_text: twenty degrees Centigrade and then add at this temperature and gradually during
about one hour in small portions at a time, about six parts of nitroso-dimethyl-
aniline hydrochlorate mixed with about three parts of water. Regulate the
temperature of the oil bath, so that the temperature of the melt gradually rises,
during this time, to about one hundred and thirty degrees Centigrade and maintain
this temperature for about three or four hours, or until it is possible to dye to the
desired shade of colour with a sample of dyestuff obtained by working up a test
portion of the melt.
Next extract the melt twice with a hot solution of caustic soda having a
temperature of say eighty to ninety degrees Centigrade. To make this solution
take each time about five parts of soda-lye (containing about thirty five per cent. of
sodium hydrate, Na OH) and about three hundred parts of water. Under the
action of the caustic soda the colouring matter, in the form of its base, is freed, and
separates out at first as a soft pitch-like mass, which however, solidifies when cold.
Wash with water and then dissolve in the requisite quantity of dilute hydrochloric
acid (containing about five per cent. of real hydrochloric acid H Cl) filter and
evaporate the solution of the hydrochlorate thus obtained to dryness.
Example 2. Add about three parts of nitroso-dimethyl aniline hydrochlorate
mixed with about one and a half parts of water to ten parts of melted para-
phenylene-diamine at a temperature of about one hundred and forty degrees
Centigrade. The addition should be made gradually in small portions at a time
during about half an hour. Maintain the aforesaid temperature until no further
formation of dye stuff can be observed and then work up exactly as described in
the previous example.
The dyestuff is a bluish-black amorphous powder readily soluble in water giving
a violet solution, it is soluble in alcohol giving a blue solution and in sulphuric acid
giving a bluish-violet colour. The dyestuff base is insoluble in ether, the alcohol
solution thereof is bluish-violet. The new dyestuff differs from the hereinbefore
mentioned unstable toluylene-blue not only in its method of production and its
stability but also in its other properties. Toluylene-blue crystallizes in black-brown
needles and gives green-blue solutions with alcohol and with water. In sulphuric
acid it forms a yellow solution. The base of the colouring matter dissolves in ether
giving a reddish-brown solution and the alcoholic solution is similarly coloured.
The dyes known as "neutral violet" and "neutral red" which are obtained by
boiling nitroso dimethyl aniline hydrochlorate in aqueous solution with respectively
meta-phenylene-diamine and meta-toluylene-diamine differ entirely from the new
dyestuff and give green solutions when dissolved in sulphuric acid.
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 :-
1) The manufacture of a blue basic dyestuff by melting together the hydrochlorate
of nitroso-dimethyl-aniline and para-phenylene-diamine with, or without, the addition
of benzoic acid, all substantially as herein before described.
2) As a new article of manufacture the blue basic dyestuff, such as can be
obtained as hereinbefore described and claimed.
ليوم
י
CT
1001
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, W.C., Agents.