IMPROVEMENTS IN THE PRODUCTION OF COLORING MATTERS SUITABLE FOR DYEING AND PRINTING
Year: 1878

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
THE PRODUCTION OF COLORING MATTERS SUITABLE FOR DYEING AND PRINTING."
A communication from abroad by Heinrich Caro, Chemist to the Badische
Aniline and Soda Works, of Mannheim, in the Empire of Germany,
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 25th February 1878.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN THE PRODUCTION OF COLORING MATTERS SUITABLE
FOR DYEING AND PRINTING." A communication from abroad by Heinrich Caro,
Chemist to the Badische Aniline and Soda Works, of Mannheim, in the Empire of
Germany.
This Invention consists in the production of red and brown coloring matters,
which in chemical language may be termed "the sulpho acids of oxyazo-napthaline,"
and the following processes may be employed for their preparation:-
First Process. Napthylamine is converted into its diazo compound by the action
of nitrous acid, and in a manner well known to chemists; and equal molecules of
the diazo compound thus obtained, and of napthol or napthylio alcohol, are allowed
to re-act upon one another by preference in an alkaline solution.
According to the employment of either of the two isomeric modifications of
napthylic alcohol known as alpha napthol and beta napthol, the result of this
operation is a precipitate containing either of the two corresponding and isomeric
modifications of oxyazon apthaline, and which may be termed "alpha and beta
oxyazon apthaline" respectively. These azo compounds are further converted into
their sulpho acids by any method now in use for the preparation of organic sulpho
acids, such as, for instance, by heating them with fuming sulphuric acid until the
mixture is found to produce a clear solution with water. The excess of sulphuric
acid may then be removed by any of the known means for effecting this purpose,

page_text: and the coloring matter may be obtained in a solid state by precipitation or
evaporation. In this manner a brown coloring matter is obtained from alpha-
oxyazo-napthaline and a red coloring matter from beta oxyazo-napthaline.
Second Process.-Napthylamine is converted into its diazo compound, as before
stated, and equal molecules of the diazo compound thus obtained, and of the sulpho
acids of either alpha napthol or beta napthol, are allowed to re-act upon each other
by preference in an alkaline solution. In this instance red coloring matters are the
result of the operation, and may be obtained in a solid state by precipitation or
evaporation.
Third Process. The sulpho acids of napthylamine are converted into their
respective diazo compounds, and equal molecules of the diazo compounds thus
obtained, and of either alpha napthol or beta napthol, are allowed to re-act upon
each other by preference in an alkaline solution. In this instance alpha napthol
produces a brown coloring matter, whilst red coloring matters result from the
employment of beta napthol.
As is well known the said sulpho acids of napthylamine may be produced in
various ways, such as, for instance, by the direct action of sulphuric acid upon
napthylamine; or in a less direct manner by treating nitro-napthaline with sulphite
of ammonium, or by submitting the sulpho acids of nitro-napthaline to the action
of reducing agents. By the said methods, as is well known, several modifications
of the sulpho acids of napthylamine are obtained, chiefly differing from each other
by their various degrees of solubility in water, some of them being nearly insoluble,
such as the so-called napthionic acid.
All these modifications of the sulpho acids of napthylamine may be converted
into the corresponding sulpho acids of oxyazo-napthaline in the manner above
described, and thus colours obtained differing in a similar ratio in their various
degrees of solubility.
Fourth Process. The sulpho acids of napthylamine are converted into their
respective diazo compounds, and equal molecules of the diazo compounds thus
obtained, and of the sulpho acids of either alpha napthol or of beta napthol, are
allowed to re-act upon each other by preference in an alkaline solution. In this
instance the disulpho acids of oxyazo-napthaline thus produced are red coloring
matters.
This Invention further consists in the production of red coloring matters, and
which may be termed "the sulpho acids of dioxyazo-napthaline," by substituting
dioxynapthaline or the diatonic napthlylic alcohol for either of the two isomeric
napthols in any of the before-mentioned processes.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the 23rd
August 1878.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN THE PRODUCTION OF COLORING MATTERS SUITABLE
FOR DYEING AND PRINTING." A communication from abroad by Heinrich Caro,
Chemist to the Badische Aniline and Soda Works, of Mannheim, in the Empire of
Germany.
This Invention consists in the production of red and brown coloring matters,
which in chemical language may be termed the "sulpho acids of oxyazo-napthaline,"
and the following processes may be employed for their preparation.
First Process. Napthylamine is converted into its diazo compound by the action
of nitrous acid, and in a manner well known to chemists; and equal molecules of
the diazo compound thus obtained, and of napthol or napthylic alcohol, are allowed
to re-act upon one another by preference in an alkaline solution.
According to the employment of either of the two isomeric modifications of
napthylic alcohol known as alpha napthol and beta napthol, the result of this
operation is a precipitate containing either of the two corresponding and isomeric
modifications of oxyazo-napthaline, and which may be termed "alpha and beta
oxyazo-napthaline" respectively. These azo compounds are further converted into
their sulpho acids by any method now in use for the preparation of organic sulpho
acids, such as, for instance, by heating them with fuming sulphuric acid. The
excess of sulphuric acid may then be removed by any of the known means for
effecting this purpose, and the coloring matter may be obtained in a solid state
by precipitation or evaporation. In this manner brown coloring matters are
obtained from alpha oxyazo-napthaline, and red coloring matters from beta oxyazo-
napthaline.
As an example of the manner in which this first process may be carried out I
proceed as follows:-About ten pounds of napthalamine are mixed with or dissolved
in about two gallons of concentrated or strong muriatic acid and about 100 gallons
of cold water, and thereto an aqueous solution of nitrate of sodium is added
containing about 4.8 (four and eight-tenths) pounds of pure nitrite of sodium, or
as much as will be found necessary to convert the napthylamine into its diazo
compound or into hydrochlorate of diazo-naphaline. The solution thus obtained is
added to an aqueous and strongly alkaline solution of about ten pounds of either of
the two isomeric napthols or of mixtures of the same, when a dark red or brown
precipitate will be produced consisting of oxyazo-napthaline, which is to be filtered,
washed, and dried.
The
In order to obtain the sulpho acids of oxyazo-napthaline I dissolve about ten
pounds of the oxyazo-napthaline in about 20 lbs. of fuming sulphuric acid
containing about 80 per cent. of anhydrous sulphuric acid, and the mixture is
heated at a temperature of about 100° Centigrade for about 2 hours, or until
a sample of the mixture will be found to produce a solution with water.
further treatment consists in removing the free sulphuric acid contained in the
mixture by any of the known means for effecting this purpose, such as, for instance,
by neutralization with caustic limo; and the coloring matter may be obtained in a
solid state, by preference in the state of a sodium salt in a manner well understood
by chemists.
Second Process.-Napthylamine is converted into its diazo compound as before
stated, and equal molecules of the diazo compound thus obtained and of the sulpho
acids of either alpha napthol or beta napthol are allowed to re-act upon each other
by preference in an alkaline solution. In this instance red coloring matters are the
result of the operation, and may be obtained in a solid state by precipitation or
evaporation.

page_text: "
The above said sulpho acids of either alpha napthol or beta napthol are produced
as is well known, by heating napthol with excess of sulphuric acid at a temperature
of about 100° Centigrade.
The resulting product is a mixture of several napthol sulpho acids, and as my
process may be applied not only to the monosulpho acids of napthol contained in
that mixture, but also to the other sulpho acids which result from the treatment of
napthol with sulphuric acid.
I wish it to be understood that what I consider as my Invention under this second
process for preparing the sulpho acids of oxyazo-napthaline is the action of diazo-
napthaline upon all sulpho acids of either alpha or beta napthol, and substantially
in the manner aforesaid. And as an example of the manner in which I prefer to
carry out this second process I take a solution of hydrochlorate of diazo-napthaline
prepared from about ten pounds of napthylamine, substantially in the manner
described in the first process; and the solution of the diazo compound is added to a
cold and strongly alkaline solution of the sodium salts of the napthol sulpho acids,
such as result from the treatment of about ten pounds of napthol with about twenty
or thirty pounds of sulphuric acid. This mixture, which throughout this operation
is to be kept alkaline, is precipitated with chloride of sodium, and the precipitate of
the coloring matter thus obtained is filtered, washed, pressed, and dried.
Third Process. The sulpho acids of napthylamine are converted into their
respective diazo compounds, and equal molecules of the diazo compounds thus
obtained, and of either alpha napthol or beta napthol, are allowed to re-act upon
each other by preference in an alkaline solution, and substantially in the manner
above described in the first and second processes. In this instance alpha napthol
produces brown coloring matters, whilst red coloring matters result from the
employment of beta napthol.
+
As is well known the said sulpho acids of napthylamine may be produced in
various ways, such as, for instance, by the direct action of sulphuric acid upon
napthylamine; or in a less direct manner by treating nitro-napthaline with sulphite
of ammonium, or by submitting the sulpho acids of nitro-napthaline to the action
of reducing agents. By the said methods, as is well known, several modifications
of the sulpho acids of napthylamine are obtained, chiefly differing from each other
by their various degrees of solubility in water, some of them being nearly insoluble,
Euch as the so-called napthionic acid.
As an example of the manner in which the sulpho acids of napthylamine may be
prepared from the sulpho acids of nitro-napthaline I proceed as follows:-One part,
by weight, of nitro-napthaline is mixed with about two parts, by weight, of rectified
sulphuric acid, and with about one part, by weight, of fuming sulphuric acid
containing about eighty per cent. of anhydrous sulphuric acid; and the mixture is
treated at a temperature of about one hundred degrees Centigrade until the
conversion into the sulpho acids of nitro-napthaline is perfect, or until a sample of
the mixture produces a clear solution with an excess of caustic alkali. The result
of this operation is then mixed with about ten parts of water and treated with
reducing agents, such as metallic iron, and in a manner well known in order to
obtain the sulpho acids of napthylamine, which may be further purified in the
following manner:-The reduction of the nitro-napthaline compounds being
complete the mixture is treated with an excess of milk of lime filtered, and the
filtered solution of the lime salts is strongly concentrated and decomposed by an
excess of muriatic acid, when the difficultly soluble sulpho acids will become
precipitated and may be separated from the more soluble modifications by filtration 5
or otherwise.
As an example of the manner in which the sulpho acids of napthylamine may be
prepared by the direct action of sulphuric acid upon napthylamine I proceed as
follows-One part, by weight, of napthylamine is mixed with about three parts,
by weight, of fuming sulphuric acid containing about eighty per cent. of anhydrous 5
sulphuric acid; and the mixture is heated at a temperature of about seventy to
eighty degrees Centigrade until a sample of the mixture produces a clear solution

page_text: with an excess of caustic alkali. The result of this operation is then mixed with
about twenty parts of water when the difficultly soluble sulpho acids will become
precipitated, and may be separated from the easily soluble modifications by filtration
or otherwise.
All these modifications of the sulpho acids of napthylamine may be converted
into the corresponding sulpho acids of oxyazo-napthaline in the manner above
described, and thus colours obtained differing in a similar ratio in their various
degrees of solubility.
Fourth Process.-The sulpho acids of napthylamine are converted into their
respective diazo compounds, and equal molecules of the diazo compounds thus
obtained and of any of the various sulpho acids of either alpha napthol or of beta
napthol are allowed to re-act upon each other by preference in an alkaline solution,
and substantially in the manner described in the foregoing processes. In this
instance the sulpho acids of oxyazo-napthaline thus produced are red coloring
matters.
This Invention further consists in the production of similar coloring matters, and
which may be termed "the sulpho acids of dioxyazo-napthaline" by substituting
dioxy-napthaline or the diatomic napthylic alcohol for either of the two isomeric
napthols in any of the before-inentioned processes.
Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect,
I would observe in conclusion that what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,―
First. The production of red and brown coloring matters, which, in chemical
language, may be termed the sulpho acids of oxyazo-napthaline by the action of the
diazo compounds, which may be prepared from napthylamine or from the sulpho
acids of napthylamine upon any of the isomeric napthols or of mixtures of the
same, or upon any of the sulpho acids which may be prepared from either alpha
napthol or from beta napthol, or from mixtures of the same, substantially by the
processes above described.
Secondly. The production of similar coloring matters, and which in chemical
language may be termed the sulpho acids of dioxyazo-napthaline by substituting
dioxy-napthaline for either of the two isomeric napthols in any of the processes
above described for the preparation of the sulpho acids of oxyazo-napthaline,
substantially as herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my Speci-
fication set my hand and seal, the Ninth day of August, One thousand eight
hundred and seventy-eight.
J. HENRY JOHNSON. (L.S.)