The Manufacture or Production of Dye-stuffs suitable for Dyeing Cotton.
Year: 1895

page_text: Date of Application, 8th June, 1895
Complete Specification Left, 9th Mar., 1896-Accepted, 11th Apr., 1896
TRUVIDIONAL
SPECIFICATION.
[Communicated from abroad by THE FARBENFABRIKEN, vormals FRIEDRICH
BAYER & Co., of Elberfeld, Germany:]
The Manufacture or Production of Dye-stuffs suitable for Dyeing
Cotton.
I HENRY EDWARD NEWTON of The Office for Patents, 6 Bream's Buildings,
Chancery Lane in the County of London, Patent Agent, do hereby declare the
nature of this invention to be as follows:-
This invention relates to the production of dyestuffs which possess the valuable
property of dyeing unmordanted cotton either in cold baths or in hot alkaline
baths containing such substances as are capable of being easily oxidised.
My foreign correspondents use, as initial materials for the said purposes,
1.8-dinitronaphthalene, 1.5-dinitronaphthalene,' or a mixture of these two
compounds, trinitronaphthalenes and tetranitronaphthalenes obtained from the
said dinitronaphthalenes, certain dinitronaphthalenesulphonic acids, and certain
dinitro halogen naphthalenes.
The coloring matters are obtained (1) by melting these nitro compounds with
alkaline sulphides or the like agents, or by treating the said nitro compounds with
alkaline sulphides or the like, in the presence of suitable solvents or diluents;
(2) by heating with acids certain compounds produced in the manner defined
in (1); (3) by further treating with alkalies, alkaline sulphides, alkaline hydro-
sulphides, alkaline sulphites, alkaline bisulphites or the like, the products obtained
by the process defined in (2).
My foreign correspondents hereafter describe more fully the processes for
practically producing these dye-stuffs.
A. DYE-STUFFS OBTAINABLE FROM DINITRONAPHTHALENES, TRINITRO-
NAPHTHALENES AND TETRANITRONAPHTHALENES.
My foreign correspondents have found that by melting with alkaline sulphides,
with alkaline hydrosulphides, or with a mixture of alkalies and sulphur or the like
agents, 1.8 dinitronaphthalene, 1.5 dinitronapbthalene, or mixtures of these dinitro-
naphthalenes, or trinitronaphthalenes and tetranitronaphthalenes which can be
produced from the said dinitronaphthalenes, dye-stuffs are obtained which have the
property of producing an unmordanted cotton, in cold baths, deep black shades fast
against the action of alkalies, acids, light, washing, and fulling.
In carrying out this process, my foreign correspondents either melt a mixture
of the said nitro compounds with alkaline sulphides or the like, until the violent
reaction which immediately takes place is finished, or they introduce the said nitro
compounds into melted alkaline sulphides, in which case the dye-stuffs can be
formed in a more profitable manner.
The researches of my foreign correspondents have shown that the quantity of
alkaline sulphide, or of the analogous compounds which can be employed in the
process with the same result, may be varied within certain limits, for example,
from two to five parts of sodium sulphide may be used for one part of dinitro-
naphthalene. Dye-stuffs are thus produced which yield on unmordanted cotton,
in cold baths, from bluish-black to deep black, or the like dark shades.
D
037

page_text: DYE-STUFFS PRODUCED FROM 1.8-DINITRONAPHTHALENE BY MEANS OF
SODIUM SULPHIDE.
2 parts of 1.8 dinitronaphthalene are introduced into 8 parts of sulphide of
sodium melted by means of the oil bath. As soon as the violent action which
immediately takes place is finished, the resulting mass is further heated until it
becomes homogeneous. The melt is then poured out, and is allowed to cool. The
stiff mass is dissolved in a small quantity of water, and the resulting solution is
filtered off. On evaporating the filtrate, the dye-stuff is obtained, forming a dark
mass which readily dissolves in water.
Unmordanted cotton, when introduced into a cold concentrated solution of the
dye-stuff, assumes deep black shades fast against the action of acids, alkalies, and
light, and also against washing and fulling.
Instead of purifying the dye-stuff, the solution in water of the melt may be
directly used for dyeing, the same shades being thus obtained.
The process takes place in an analogous manner, if, instead of 1.8 dinitro-
naphthalene used in the foregoing Example I, other derivatives of naphthalene are
employed, such as the mixture of 1.8 dinitronaphthalene and 1.5 dinitronaphthalene
obtainable by nitrating naphthalene in the generally known manner, or 1.5 dinitro-
naphthalene or trinitro and tetranitronaphthalenes derived from 1.8 dinitro and
1.5 dinitro naphthalene, or the mixture of dinitro trinitro, and tetranitronaphthalenes
which can be obtained by nitrating naphthalene or dinitronaphthalene. My
foreign correspondents use, for instance, alphatrinitronaphthalene, betatrinitro-
naphthalene, gammatrinitronaphthalene (see Beilstein, II. edition, vol. 2,
page 148), deltatrinitronaphthalene (see Berichte der Deutschen Chem. Gesells-
chaft, XXVII, page 378), alphatetranitronaphthalene, betatetranitronaphthalene
(see Beilstein, II. edition, vol. 2, page 148), gammatetranitronaphthalene, delta-
tetranitronaphthalene (see Berichte der Deutchen Chem. Gesellschaft, XXVIII,
page 378), or mixtures of such polynitro derivatives of naphthalene which can be
obtained by nitrating naphthalene or derivatives thereof.
On melting the said compounds together with sulphide of sodium or the like,
black dye-stuffs are obtained which in general are similar to that produced as
described in the above Example I, and which possess the property of yielding on
unmordanted cotton, in cold baths, dark shades fast against the action of acids,
alkalies, and light.
In the process defined in the Example I, other alkaline sulphides, or alkaline
hydrosulphides, or mixtures of alkalies and sulphur, or the like, may be used, dye
stuffs being thus obtained which are in general identical with that produced as
described in the preceding Example 1.
The process may also be carried out in heating a mixture of the said nitro
derivatives of naphthalene with alkaline sulphide, or other agents acting in the
same or a similar manner.
My foreign correspondents have further found, that dye-stuffs can be obtained
which have the valuable property of producing on unmordanted cotton, in cold
baths, deep blue shades fast against the action of alkalies, acids, light, and also
against washing and fulling, which process consists in acting on the said dinitro-
naphthalenes, trinitronaphthalines, and tetranitronaphthalenes, or mixtures thereof,
with greater quantities of alkaline sulphides, or of substances or mixtures acting in
the same or a similar manner.
Such blue dye-stuffs are also obtained either by melting a mixture of the said
nitro derivatives of naphthalene with alkaline sulphides or the like bodies, or by

page_text: gradually introducing the said nitro compounds into melted alkaline sulphides, or
the like, and subsequently heating until the mass has become homogeneous.
My foreign correspondents have ascertained that blue cotton dyes are also
obtained by heating the said nitro compounds with alkaline sulphides, or with
bodies which act in an analogous manner in the presence of water or alcohol or
other solvents or diluents, or by stirring the nitro compounds into a heated watery
or other solution of alkaline sulphides and the like. The researches of my foreign.
correspondents have shown that one part by weight of 1.8 dinitronaphthalene, and
from 6 to 18 parts of alkaline sulphide or the like may be profitably used in order
to produce blue cotton dye-stuffs.
The following example will serve to illustrate the manufacture of the said
dye-stuffs. The parts are by weight.
BLUE DYE-STUFF OBTAINED FROM 1.8-DINITRONAPHTHALENE BY MEANS
OF SODIUM SULPHIDE.
A mixture prepared from 12 parts of sodium sulphide and 1 part of 1.8 dinitro-
naphthalene is heated until it has changed into a darkish blue homogeneous liquid,..
and the effervescence which takes place is finished. The melt, after being poured
out, and when cool, is dissolved in a small quantity of water. This solution is
filtered off, and the filtrate is evaporated. In this manner, the dye-stuff is
obtained, forming a dark mass with metallic lustre. When dissolved in a sinall
quantity of cold water, it produces on cotton, in cold baths, deep-blue fast
shades.
For dyeing purposes, the solution in water of the melt may be used directly,
instead of previously separating the dye-stuff, as above described.
Analogous dye-stuffs are produced on melting with alkaline sulphides, or the
like, the mixture of 1.8 and 1.5 dinitrouaphthalene, such as can be obtained by
nitrating, naphthalene or on using 1.5 nitronaphthalene, or the trinitro and tetra-
nitronaphthalenes hereinbefore enumerated.
The process may also be carried out by stirring the said nitro compounds into
melted alkaline sulphides or the like.
The dye-stuffs thus obtained have the property of yielding, in cold baths, fast
deep-blue shades on unmordanted cotton.
My foreign correspondents have further found, that by heating with acids the
dye-stuffs obtained by the processes defined in the above Examples I and II from
dinitro, trinitro, and tetranitronaphthalenes, products are obtained which have the
property of dyeing unmordanted cotton in hot alkaline baths in the presence of
substances capable of being readily oxidised, such as grape sugar, glycerinol, and
the like. By a treatment with alkalies, or alkaline sulphides, or alkaline hydro-
sulphides or the like, these products are changed into dye-stuffs which directly dye
unmordanted cotton in cold baths.
The process which my foreign correspondents use in order to produce such
dye-stuffs, is illustrated by the following example, the parts being by weight.
One part of gammatrinitronaphthalene (NO, NO, NO, = 1.4.8) (see Berichte
der Deutchen Chem. Gesellschaft, XXVIII, page 378), reduced to as fine a state of
subdivision as possible, is added to 150 parts of water. The liquid is boiled for
some time, and 12 parts of crystalline sodium sulphide are then added. The
trinitronaphthalene is gradually dissolved, the liquid assuming a brownish-black
color. After further heating during about half an hour, the liquid is filtered, and.

page_text: the hot filtrate is mixed with 10 parts of concentrated muriatic acid. A greyish-.
black precipitate is thus separated, and the acid mixture is heated during some
time. After cooling, the precipitate is filtered off, and the intermediate product
thus obtained as a bluish-black mass is washed with cold water. When treated
with alkalies or alkaline sulphides or alkaline sulphites, or alkaline bisulphites, it
yields a black dye-stuff which profitably is used in pasty form for dyeing.
It produces on unmordanted cotton, in cold baths, black shades.
The first obtained intermediate product may be directly used for dyeing
purposes, as it yields, on unmordanted cotton, black shades in hot alkaline
baths, to which oxidisable substances such as grape sugar, glycerinol or the like,
are added.
In the above Example III, the quantity of alkaline sulphides or the like may be
varied within large limits.
Analogous dye-stuffs are obtained if gamma trinitronaphthalene used in the
Example III is replaced by other trinitronaphthalenes or tetra nitronaphthalenes
derived from 1.5 dinitronaphthalene or 1.8 dinitronaphthalene, such as alpha-
trinitronaphthalene, betatrinitronaphthalene, alphatetranitronaphthalene, betatetra-
nitronaphthalene, gammatetranitronaphthalene, deltatetranitronaphthalene (see
Beilstein, edition II, vol. 2, page 148, and Berichte der Deutschen Chem.
Gesellschaft, XXVIII, page 378), and the like, or mixtures thereof.
By means of the process illustrated in the Example III, the said nitro compounds
are converted into dye-stuffs which produce dark fast shades on unmordanted cotton
in alkaline baths to which, oxidisable substances have been added, and which are
converted into other dye-stuffs when they are treated with alkalies, alkaline
sulphides, alkaline hydrosulphides, alkaline sulphites or bisulphites, as hereinbefore
described.
B. DYE STUFFS OBTAINED FROM DINITRONAPHTHALENESULPHONIC
ACIDS.
My foreign correspondents have further found, that either by boiling with
solutions or dilutions of alkaline sulphides or the like, or by melting with such
agents sulphonic acids of 1.8 dinitronaphthalene or 1.5 dinitronaphthalene, or
mixtures thereof, new valuable dye-stuffs are produced which yield on unmordanted
cotton, in cold baths, from blue to bluish-black and black shades.
Amongst the dinitronaphthalenesulphonic acids, for instance, the 1.8-dinitro-
naphthalene 4 sulphonic acid may be used. This acid can easily be prepared by
nitrating 1.5 nitronaphthalene sulphonic acid in sulphuric acid solution.
The following example may serve to illustrate the production of dye-stuffs from
dinitronaphthalene sulphonic acids. The parts are by weight.
DYE-STUFF
OBTAINED FROM 1.8 DINITRONAPHTHALENE 4 SULPHONIC ACID
BY MEANS OF POTASSIUM HYDROSULPHIDE.
10 parts of 1.8 dinitronaphthalene 4 sulphonic acid are slowly stirred into 40 parts.
of a 30 per cent. solution of potassium hydrosulphide. The temperature rises
spontaneously, and a violent reaction takes place. As soon as the first energetic
action is finished, the mass is heated for some time.
The thus obtained solution, when cool, may be directly used for dyeing or the
pure dye-stuff may be isolated from the solution by salting out, filtering off, and
drying. It yields violet-black shades on unmordanted cotton in cold baths,
to which a small quantity of caustic soda lye or sodium carbonate, is profitably
added.
The action proceeds in an analogous manner if solutions of other alkaline.
sulphides, or if solid alkaline sulphides or the like, be employed in the process.

page_text: DYE-STUFF OBTAINED FROM DINITRO CHLORONAPHTHALENE BY. MEANS OF
SODIUM SULPHIDE.
45 parts of dinitro chloronaphthalene prepared in the above described manner.
are introduced into a boiling solution of 225 parts of crystallised sodium.
sulphide (Na, S + 9 H₂O) in 1000 parts of water, a violent action taking place, and.
the mass being spontaneously heated to boiling. As the dinitrochloronaphthalene.
becomes dissolved, the liquid assumes a darkish-red color. As soon as the
intensity of the color no longer increases, the resulting liquid is filtered, and the
filtrate thus obtained is mixed with 500 litres (in case the parts are kilos. by weight)
of muriatic acid (20° Bé.), and is boiled during about one hour. A precipitation
of grey color is thus formed, which by-and-by becomes deep black, and at the end of
this time the origiual grey precipitate assumes a deep black color. It is isolated
by filtration. It is insoluble in sodium carbonate and dilute soda lye, but readily
dissolves in a solution of sodium sulphide or the like, and in strong soda-lye or the-
like, and in alkaline sulphite and bisulphite, yielding violet-black solutions, from
which the dye-stuff does not precipitate on cooling. Unmordanted cotton, when
introduced into such cold alkaline solutions of the dye-stuff, and when allowed to-
remain there during from 3.to 24 hours, assumes from bluish-grey to deep black-

page_text: shades, fast against the action of light and of acids and likewise against washing
and fulling.
Similar dye-stuffs are obtained on using in the process illustrated by the
foregoing. Example V, other dinitrohalogennaphthalenes, instead of that obtained
from alphachloronaphthalene by means of fuming nitric acid as hereinbefore
described. The result of the process is not affected if other quantities of sodium.
sulphide are employed, but according to the researches of my foreign corre-
spondents, it is not profitable to use very small quantities of these agents, or
to effect the formation of the dye in too dilute a solution, as only a relatively small
quantity of the dye-stuff is produced, if, for example, 5000 or 6000 parts of water
are used for dissolving the aforesaid 225 parts of sodium sulphide.
My foreign correspondents do not limit themselves to the particulars given in the
above examples, as these may be varied within certain limits, and all processes can
be employed which are known and in use for analogous purposes.
Such modifications do not alter the nature of this invention, which in general
relates, on the one hand, to the production of dye-stuffs from dinitro naphthalenes,
trinitronaphthalenes, tetranitronaphthalenes, dinitronaphthalene sulphonic acids, or
dinitrohalogennaphthalenes, either by melting these compounds together with
alkaline sulphides, alkaline hydrosulphides, mixtures of alkalies with sulphur, or
the like agents acting in the same or a similar manner, or by boiling the said nitro
compounds with solutions or dilutions of alkaline sulphides or the like, or by
introducing the said nitro compounds into melted alkaline sulphides and the like, or
solutions or dilutions thereof, dye-stuffs being thus produced which have the
valuable property of yielding on unmordanted cotton, in cold baths, dark fast
shades, and, on the other hand, to the production of certain intermediate products
capable of dyeing unmordanted cotton in hot alkaline baths containing oxidisable
substances, viz., by heating the before mentioned dye stuffs with acids, and to the
manufacture of dye-stuffs dyeing unmordanted cotton in cold baths, viz., by
treating these intermediate products with alkalies, alkaline sulphides, alkaline
sulphites, alkaline bisulphites, or the like agents.
Dated this 8th day of June 1895.
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION.
The Manufacture or Production of Dye-stuffs suitable for Dyeing
Cotton.
I, HENRY EDWARD NEWTON of The Office for Patents, Bream's Buildings,
Chancery Lane in the County of London, Patent Agent, do hereby declare 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 dye-stuffs which possess the valuable
property of dyeing unmordanted cotton, either in cold baths, or in hot alkaline
baths containing substances capable of being easily oxydised.
My foreign correspondents use initially, as materials for the said purposes,
1.8 dinitronaphthalene, 1.5 dinitronaphthalene, or a mixture of these two compounds,
the trinitronaphthalenes and tetravitronaphthalenes, obtained from the said dinitro-
naphthalenes certain dinitronaphthalene sulphonic acids, and certain dinitrohalogen
derivatives of naphthalenes.
The colouring matters are obtained
(1.) By melting these nitro compounds with alkaline sulphides or similar agents,
or by the action of the said nitro compounds of alkaline sulphides or the like, in
the presence of suitable solvents or diluents;

page_text: weaving certain compounds produced in the manner defined in (1.) with
acids;
(3.) By the further action of alkalies, alkaline sulphides, alkaline hydrosulphides,
alkaline sulphites, alkaline bisulphites, or the like, on the products obtained by the
process defined in (2).
My foreign correspondents hereinafter more fully describe the processes for
practically producing these dyestuffs.
A. DYE STUFFS OBTAINABLE FROM DINITRONAPHTHALENES, TRINITRO-
NAPHTHALENES, AND TETRANITRONAPHTHALENES.
My foreign correspondents have found that on melting mixtures of alkaline
sulphides, of alkaline hydrosulphides, of a mixture of alkali and sulphur, or of
similar agents, with either 1.8 dinitronaphthalene, or 1.5 dinitronaphthalene, or
mixtures of these dinitronaphthalenes, or trinitronaphthalenes, and tetranitro-
naphthalenes which can be produced from the said dinitronaphthalenes, dyestuffs
are obtained which have the property of dyeing unmordanted cotton in cold baths,
deep black shades which withstand the action of alkalies, acids, light, washing,
and fulling.
In carrying out this process, my foreign correspondents either melt a mixture
of the said nitro compounds with alkaline sulphides, or the like, until the violent
action which immediately sets in, is finished, or they introduce the said nitro
compounds into molten alkaline sulphides, the latter being the more advantageous
method.
The researches of my foreign correspondents have shewn that the amount of
alkaline sulphide, or analogous compounds, used in the process, may be varied
within certain limits; for example, from two to five parts of sodium sulphide may
be taken for one part of dinitronaphthalene. Dye-stuffs are thus produced which
dye unmordanted cotton in cold baths, dark shades varying from bluish-black to
deep black.
In order to illustrate the process for the production of the last-defined dye-
stuff's, my foreign correspondents give the following example, the parts being by
weight.
EXAMPLE I.
DYE-STUFF PRODUCED FROM 1.8 DINITRONAPHTHALENE BY MEANS OF
SODIUM SULPHIDE.
2 parts of 1.8 dinitronaphthalene are introduced into 8 parts of sulphide of
sodium, melted by means of an oil-bath. As soon as the violent action which
immediately sets in is finished, the mass is further heated until it becomes
homogeneous. The melt is then poured out, and is allowed to cool.
The stiff
On
mass is dissolved in a small quantity of water, and the solution is filtered.
evaporating the filtrate, the dye-stuff is obtained in the form of a dark mass which
readily dissolves in water.
On introducing unmordanted cotton into a cold concentrated solution of the
dye-stuff, it is dyed a deep black shade which withstands the action of acids,
alkalies, and light, and also washing and fulling.
Instead of purifying the dyestuff, the solution of the melt, in water, may be
directly used for dyeing, the same shades being thus obtained.
The process is carried out in an analogous manner, if, instead of the
1.8 dinitronaphthalene prescribed in the foregoing Example I, other derivatives of
naphthalene are used, such as the mixture of 1.8 dinitronaphthalene and
1.5 dinitronaphthalene obtainable by nitrating naphthalene in the well-known
manner, or 1.5 dinitronaphthalene, or the trinitro and tetranitronaphthalenes
derived from 1.8 dinitro and 1.5 dinitronaphthalene, or the mixture of dinitro,
trinitro, and tetranitronaphthalenes which can be obtained by nitrating naphthalene
or dinitronaphthalene. My foreign correspondents use, for instance, alpha-trinitro-

page_text: naphthalene, betatrinitro-naphthalene, gamma-trinitronaphthalene (see Beilstein,
II. edition, vol. 2, page 148), deltatrinitronaphthalene (see Berichte der Deutschen
Chemischen Gesellschaft, XXVIII, page 378), alphatetranitronaphthalene, beta-
tetranitronaphthalene (see Beilstein, II. edition, vol. II, page 148), gamma-
tetranitronaphthalene, deltatetranitronaphthalene, (see Berichte der Deutschen
Chemischen Gesellschaft, XXVIII, page 378), or mixtures of such polynitro
derivatives of naphthalene which can be obtained by nitrating naphthalene or
derivatives thereof.
On melting the said compounds together with sulphide of sodium or the like,
black dye-stuffs are obtained which, speaking generally, are similar to that
produced as described in the above Example I, and which possess the property
of dyeing unmordanted cotton, in cold baths, dark shades, which withstand the
action of acids, alkalies, and light.
In the process defined in the Example I, other alkaline sulphides, or alkaline
hydro-sulphides, or mixtures of alkalies and sulphur, or the like, may be used,
dyestuffs being thus obtained which, in general; are identical with that produced as
described in the preceding Example I.
The process may also be carried out by heating a mixture of the said nitro-
derivatives of naphthalene with alkaline sulphides, or other agents acting in the
same or a similar manner.
My foreign correspondents have further found, that dye-stuffs can be obtained
which have the valuable property of dyeing unmordanted cotton, in cold baths,
deep blue shades, which withstand the action of alkalies, acids, light, and also
washing and fulling, the which process consists in acting on the said dinitro-
naphthalenes, trinitronaphthalenes, and tetranitronaphthalenes, or mixtures thereof,
with still larger proportions of alkaline sulphides, or of substances or mixtures
acting in the same or a similar manner.
Such blue dyestuffs are also obtained either by melting a mixture of the said
nitro-derivatives of naphthalene with alkaline sulphides or similar bodies, or by
gradually introducing the said nitro compounds into melted alkaline sulphides or
the like, and subsequently heating until the mass becomes homogeneous.
My foreign correspondents have ascertained that blue cotton dyes are also
obtained by heating the said nitro compounds with alkaline sulphides, or with
substances which act in an analogous manner, in the presence of water or alcohol,
or other solvents or diluents, or by stirring the nitro compounds into a heated
The researches of my
aqueous or other solution of alkaline sulphides and the like.
foreign correspondents have shewn that one part, by weight, of 1.8 dinitro
naphthalene, & from 6 to 18 parts of alkaline sulphide, or the like, may be used
with advantage in producing blue cotton dye stuffs. The following example will
serve to illustrate the manufacture of the said dyestuffs; the parts are by weight.
EXAMPLE II.
BLUE DYE-STUFF OBTAINED FROM 1.8 DINITRO NAPHTHALENE BY MEANS OF
SODIUM SULPHIDE.

page_text: naphthalene, or on using 1.5 dinitronaphthalene, or the trinitro and tetranitro-
naphthalenes herein before enumerated.
The process may also be carried out by stirring the said nitro compounds into
melted alkaline sulphides, or the like.
The dye-stuffs thus obtained have the property of producing fast deep-blue shades
on unmordanted cotton, even in cold baths.
My foreign correspondents have further found, that if the dye-stuffs obtained by
the processes defined in the above Examples I and 11, from dinitro-, trinitro-, and
tetranitronaphthalenes, are heated with acids, products are obtained which have the
property of dyeing unmordanted cotton in hot alkaline baths, in the presence of
substances capable of being readily oxydized, such as grape sugar, glycerol, and
the like. On treatment with alkalies, or alkaline sulphides, or alkaline hydro-
sulphides, or the like, these products are converted into dye-stuffs which directly
dye unmordanted cotton in cold baths.
The process which my foreign correspondents use in order to produce such dye-
stuffs is illustrated by the following example, the parts being by weight.
:
=
1.4.8) (see Berichte
reduced to as fine a
The liquid is boiled
One part of gammatrinitronaphthalene (NO₂: NO, NO,
der Deutschen Chemischen Gesellschaft XXVIII, page 378),
state of subdivision as possible, is added to 150 parts of water.
for some time, and 12 parts of crystalline sodium sulphide are then added. The
trinitronaphthalene is gradually dissolved, the liquid assuming a brownish-black
colour. After further heating during about half an hour, the liquid is filtered, and
the hot filtrate is mixed with 10 parts of concentrated muriatic acid, which causes
the separation of greyish-black precipitate. After the acid mixture has been
heated for some time, the liquid is allowed to cool, and the precipitate is then
filtered off, and the intermediate product thus obtained as a bluish-black mass, is
washed with cold water. When treated with alkalies or alkaline sulphides, or
alkaline sulphites, or alkaline bisulphites, it yields a black dye-stuff, which is
advantageously used for dyeing in a pasty form. It produces black shades on
unmordanted cotton in cold baths.
The intermediate product first obtained may be directly used for dyeing purposes,
as it dyes unmordanted cotton black shades in hot alkaline baths containing
oxidisable substances, such as grape sugar, glycerol or the like.
In the above Example III, the quantity of alkaline sulphides, or the like, may
be varied within wide limits.
Analogous dye-stuffs are obtained by using, instead of the gammatrinitro-
naphthalene prescribed in Example III, other trinitronaphthalenes or tetranitro-
naphthalenes derived from 1.5 dinitronaphthalene or 1.8 dinitronaphthalene, such as
alphatrinitronaphthalene, betatrinitronaphthalene, alpha tetranitronaphthalene,
betatetranitronaphthalene, gammatetranitronaphthalene, deltatetranitronaphthalene
(see Beilstein, edition II, vol. 2, page 148, and Berichte der Deutschen Chemischen"
Gesellschaft, XXVIII, page 378), and the like, or mixtures thereof.
By means of the process illustrated in the Example 111, the said nitro compounds
are converted into dye-stuffs which produce fast dark shades on unmordanted cotton,
in alkaline baths containing oxidisable substances, and which are converted into
other dye-stuffs, when treated with alkalies, alkaline sulphides,. alkaline hydro-
sulphides, alkaline sulphites, or bisulphites, as herein before described.

page_text: sulphonic acids of 1.8 dinitronaphthalene, or 1.5 dinitronaphthalene, or mixtures
thereof, afford new valuable dye-stuffs, dyeing unmordanted cotton in cold baths
from blue to bluish-black and black shades.
1.8 dinitronaphthalene 4 sulphonic acid may be used in this manner, for instance.
This acid can easily be prepared by nitrating 1.5 nitro naphthalene, sulphonic acid
dissolved in sulphuric acid.
The following example may serve to illustrate the production of dye-stuffs from
dinitro naphthalene sulphonic acids. The parts are by weight.
DYE STUFF obtained frOM 1.8 DINITRONAPHTHALENE 4-SULPHONIC ACID,
BY MEANS OF POTASSIUM HYDROSULPHIDE.
10 parts of 1.8 dinitronaphthalene 4-sulphonic acid are slowly stirred into
40 parts of a 30 per cent. solution of potassium hydrosulphide. The temperature
rises spontaneously, and a violent action takes place. As soon as the first energetic
action is at an end, the mass is heated for some time.
The solution thus obtained, when cool, may be directly used for dyeing, or the
pure dye-stuff may be isolated from it by salting out, filtering off, and drying. It
yields violet-black shades on unmordanted cotton in cold baths, to which a small
quantity of caustic soda-lye, or sodium carbonate, is advantageously added.
The action proceeds in an analogous manner, if solutions of other alkaline
sulphides, or if solid alkaline sulphides, or the like, be used in the process.
Similar dye-stuffs are obtained, if other 1.8 dinitronaphthalene sulphonic acids,
or 1.5 dinitro-naphthalene sulphonic acids, or mixtures thereof, are acted on with
alkaline sulphides, or the like, instead of using 1.8 dinitronaphthalene 4-sulphonic
acid, as described in the foregoing Example IV.
For instance, the following dinitronaphthalene sulphonic acids may be
used, viz. :-
:-
1.8-dinitronaphthalene 3 sulphonic acid.
1.5 dinitronaphthalene 7 sulphonic acid.
1.8 dinitronaphthalene 3.6 disulphonic acid.
1.5 dinitronaphthalene 3.7 disulphonic acid.
The researches of my foreign correspondents have shewn, that the dye-stuffs thus
produced by treatment with acids in the manner described in the above
Example III, are converted into products which dye unmordanted cotton in hot
alkaline baths containing substances capable of being readily oxidised. These
intermediate products can also be converted by a subsequent treatment with alkalies,
or alkaline sulphides or the like, into dye-stuffs which directly dye unmordanted
cotton in cold baths.
C. DYE STUFFS OBTAINED FROM
DINITROHALOGEN
NAPHTHALENE.
DERIVATIVES OF
My foreign correspondents have further found that halogen derivaties of dinitro
naphthalenes can be used for the production of dye-stuffs having the property of
dyeing unmordanted cotton, dark shades, even in cold baths. Such dye-stuffs are
obtained by the action of alkaline sulphides, or the like agents, on dinitro halogen
derivatives of naphthalene. For instance, the mixture of dinitro-chloronaphthalenes
obtainable by acting on alphachloronaphthalene with fuming nitric acid or the like
(see Berichte der Deutschen Chemischen Gesellschaft, IX, 927 and 928), may be
used for the said purposes, as, when subjected to treatment with alkaline sulphides,
or similar agents, and then to the action of heated acids, this mixture is converted
into a products which, when dissolved in alkaline sulphides, alkaline hydrosulphides,
alkaline sulpites, alkaline bisulphites, or the like, can be used in dyeing cotton in
cold baths, from bluish-grey to deep black shades.