mals FRIEDRICH The Manufacture or Production of Dyestuffs for Cotton.
Year: 1899

page_text: [Communicated from abroad by THE FARBEN FABRIKEN,
BAYER & Co., of Elberfeld, Germany.]
voimals FRIEDRICH
The Manufacture or Production of Dyestuffs for 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:-
My foreign correspondents have found that new violet dye-stuffs for cotton can
be obtained from amido-alpha, alpha,-dihydroxynaphthalene sulphonic acids,
or all those substances, for instance, nitroso alpha, alpha, dihydroxynaphthalene
sulphonic acids, and the azo colouring matters of alpha, alpha, dihydroxynaphtha-
lene sulphonic acids, which, by way of reduction, are converted into amido alpha,
alpha, dihydroxynaphthalene sulphonic acids. This process, in general, consists
in subjecting the said derivatives of alpha, alpha,-dihydroxynaphthalene sulphonic
acids to the action of sulphur and alkaline sulphide, alkaline polysulphides,
mixtures of alkalies and sulphur or the like alkaline-sulphide carrying com-
pounds, at elevated temperatures. In this manner products are formed which, by
a suitable treatment, can be readily separated into two distinct dyestuffs; the
one of which yields violet shades on cotton, while the other produces from grey to
brown shades on cotton. The said separation can be effected in a very simple way
by repeatedly extracting the above products, previously pulverised, with small
quantities of hot water, filtering the solutions thus formed, continuing this
extraction until the readily soluble component part has been wholly dissolved
out, and, finally, precipitating from the joint filtrates the dye-stuffs by the
addition of common salt, zinc chloride, or the like. The colouring matters thus
obtained yield violet shades on cotton in boiling baths containing grape sugar
and sodium carbonate, alkaline sulphide, or the like reducing agents, and likewise
in cold baths containing alkaline sulphide, or the like, while the less readily
soluble or insoluble bye-products remaining on the filter produce from grey to
brown shades in baths to which alkaline sulphide or the like is added.
The following example is given in order to illustrate the isolation of the
hereinbefore defined violet cotton dye-stuffs. The parts are by weight.
EXAMPLE.
50
110 parts of dry sodium sulphide 100 parts of sulphur, and
parts of water, are mixed and heated, until the formation of the sodium-poly-.
sulphide is finished. 55 parts of nitroso-alpha, alpha, dihydroxynaphthalene
alpha, beta, disulphonic acid are subsequently stirred into the above poly-sulphide
solution, and stirring is continued until the nitroso compound has dissolved. The
liquid mass is then slowly heated' (with continual stirring) in an iron vessel, to
from 200 to 210 degrees Centigrade, and kept at this temperature, until
it has become solid and can be readily pulverised. When this stage is

page_text: reached, the vessel is closed, and the temperature raised to from 240 to 250 degrees
Centigrade, at which temperature, heating is continued for from about 3 to
4 hours, that is to say, until the bluish-red watery solutions of two subsequent
samples taken from the melt, no longer show an increase of intensity. The
resulting raw melt, when cold is pulverised, and repeatedly treated with small
quantities of hot water. The solutions are filtered, and this extraction is con-
tinued, until the readily soluble component part has been wholly dissolved out.
From the joint filtrates, the violet cotton dye-stuff is precipitated by the addition
of common salt, or, more profitably, zinc chloride. When filtered off, pressed,
dried, and pulverised, this colouring matter forms a greyish-black powder
insoluble in .cold and boiling water. It dyes a bright violet on cotton in cold
or hot baths containing the above-defined reducing agents. The shades are fast
to washing and light.
The other violet cotton dye-stuffs are obtained in an analogous manner, if the
nitroso-alpha-alpha, dihydroxynaphthalene alpha, beta, disulphonic acid used
in the above example is replaced by other nitroso alpha, alpha, dihydroxynaph-
thalene di- or mono-sulphonic acids, or by amido alpha, alpha, dihydroxynaphtha-
lene mono- or poly-sulphonic acids, or by azo-dye-stuffs derived from alpha,
alpha, dihydroxynaphthalene mono- or poly-sulphonic acids.
The sodium sulphide and sulphur prescribed in the above example may be
replaced by other alkaline-sulphide carrying compounds, as hereinbefore defined.
The proportions and the temperatures given may also be varied within certain
limits.
SO
According to the further researches of my foreign correspondents, the process
herein before illustrated can also be carried out more profitably,
that the formation of grey or brown bye-products is entirely, or almost entirely,
avoided. This effect is attained by heating the aforesaid derivatives of alpha₁
alpha dihydroxynaphthalene sulphonic acids with alkaline-sulphide carrying
compounds, in the presence of zinc or zinc compounds. By this slight variation,
melts are obtained which, when applied to cotton directly, dye violet shades fast
against the action of alkalies and light. In this case, the above mentioned
extraction of the melt, and the further operations, are unnecessary.
This modified process is illustrated by the following example. The parts are
by weight.
EXAMPLE.
30 parts of nitroso-alpha-alpha, dihydroxynaphthalene alpha, beta, disul-
phonic acid are dissolved in 20 parts of water and 82 parts of soda-lye (containing
30 per cent. of Na OH); 20 parts of dry zinc chloride are added, and subsequently
66 parts of dry sodium sulphide; and 60 parts of sulphur are stirred into the
resulting mixture. The mass is heated in an iron vessel to 200 degrees Centi-
grade (stirring the while), and heating is continued at this temperature until
the mass has become solid, and can be readily pulverised. At this stage, the
vessel is closed and the temperature is raised to 240 degrees Centigrade. Heat-
ing is then continued for from 2 to 3 hours at this temperature. The blackish
mass thus obtained dissolves in water with a violet colour, whereas a small
residue, probably consisting of zinc sulphide, remains undissolved.
It dyes a bright violet on cotton in boiling baths, to which common salt and
sodiuni carbonate are profitably added. The shades thus obtained are fast against
the action of alkalies and light.
Other violet dyestuffs for cotton are obtained, if other nitroso alpha, alpha
dihydroxynaphthalene di- or mono-sulphonic acids, or if amido alpha, alpha,
dihydroxynaphthalene mono- or di-sulphonic acids, or the azo dye-stuffs derived
from alpha, alpha, dihydroxynaphthalene mono- or di-sulphonic acids, are used in
place of the nitroso-alpha, alpha, dihydroxynaphthalene-alpha, beta, disulphonic
acid employed in the last example. The zinc chloride prescribed therein can be
replaced by other zinc compounds, such as zinc sulphate, zinc carbonate, zinc

page_text: oxide, or the like, or also by metallic zinc, which is profitably used in the form
of zinc dust.
The proportions & temperatures mentioned in the second example can be
varied within certain limits; other alkaline-sulphide carrying compounds can be
used in place of sodium sulphide and sulphur. In all cases, melts are obtained
which directly yield, on cotton, violet shades fast against the action of alkalies
and light.
13
The Manufacture or Production of Dye-stuffs for 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 and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
My foreign correspondents have found that new violet dyestuffs for cotton can
be obtained from the following alpha 1 alpha 4-dihydroxynaphthalene sulphonic
derivatives, viz., amido-alpha 1-alpha 4-dihydroxynaphthalene sulphonic acids,
nitroso-alpha 1 alpha 4 dihydroxynaphthalene sulphonic acids, and the azo
colouring matters resulting from the combination of diazo compounds with
alpha 1 alpha 4-dihydroxynaphthalene sulphonic acids. For this process, my
foreign correspondents start from the products obtainable by subjecting the said
derivatives of alpha 1 alpha 4-dihydroxynaphthalene sulphonic acids to the
action of sulphur and alkaline sulphides, alkaline polysulphides, mixtures of
alkalies and sulphur, or the like alkaline sulphide-carrying compounds, at elevated
temperatures.
According to the researches of my foreign correspondents, the products thus
formed can, by a suitable treatment, be readily separated into two distinct dye-
stuffs, the one of which yield's violet shades on cotton, while the other produces
from gray to brown shades on cotton. The said separation can be effected in a
very simple way, by repeatedly extracting the above products, previously
pulverised, with small quantities of hot water, filtering the solutions thus formed,
continuing this extraction, until the readily soluble component part has been
wholly dissolved out, and finally precipitating from the joint filtrates the dye-
stuffs by the addition of common salt, zinc-chloride, or the like. The
colouring matters thus obtained yield violet shades on cotton in boiling baths
containing grape sugar and sodium carbonate, alkaline sulphide, or the like
reducing agents and likewise in cold baths containing alkaline sulphide or the
like, whilst the less readily soluble or insoluble by-products remaining on the
filter produce from gray to brown shades in baths to which alkaline sulphide
or the like is added."
The following example is given in order to illustrate the isolation of the
herein before defined violet cotton dye-stuffs. The parts are by weight.
EXAMPLE A.
110 parts of dry sodium sulphide, 100 parts of flowers of sulphur, and 50
parts of water, are mixed and heated, until the formation of the sodium poly-
sulphide is finished. 55 parts of nitroso-alpha 1-alpha 4-dihydroxynaphthalene
alpha 2 beta 1 disulphonic acid are subsequently stirred into the above

page_text: polysulphide solution, and stirring is continued, until the nitroso com-
pound has dissolved. The liquid mass is then slowly heated (with
continual stirring), in an iron vessel, profitably by means of a
metallic bath, to from 200 to 210 degrees Centigrade, and kept at this temperature,
until it has become solid, and can be readily pulverized. When this stage is
reached, the vessel is closed, and the temperature raised to from 240 to 250 degrees
Centigrade, at which temperature heating is continued for from about 3 to
4 hours, that is to say, until the bluish-red watery solutions of two subsequent
samples taken from the melt, no longer show an increase of intensity. The
resulting raw melt, when cold is pulverized, and repeatedly treated with small
quantities of hot water. The solutions are filtered, and this extraction is con-
tinued, until the readily soluble component part has been wholly dissolved out.
From the joint filtrates, the violet cotton dye-stuff is precipitated by the addition
of common salt, or, more profitably, zinc chloride. When filtered off, pressed,
dried, and pulverized, this colouring matter forms a greyish-black powder
insoluble in cold and boiling water. It dyes a bright violet on cotton in cold
or hot baths containing the above-defined reducing agents. The shades are fast
to washing and light.
The other violet cotton dye-stuffs are obtained in an analogous manner, if the
nitroso-alpha 1 alpha 4-dihydroxynaphthalene alpha 2 beta 1 disulphonic acid used
in the above example is replaced by other nitroso alpha 1 alpha dihydroxy-
naphthalene di- or monosulphonic acids, or by amido alpha 1 alpha 4-dihydroxy-
naphthalene mono- or polysulphonic acids, or by azo dye-stuffs derived from
alpha 1 alpha 4 dihydroxynaphthalene mono- or polysulphonic acids.
The said amido alpha 1 alpha 4-dihydroxynaphthalene sulphonic acids can be
prepared by reducing either the corresponding nitroso alpha 1 alpha 4 dihydroxy-
naphthalene sulphonic acids, or the azo dye-stuffs resulting from the combination
of diazo compounds with alpha 1 alpha 4 dihydroxynaphthalene sulphonic acids.
The production of the violet dye-stuffs from amido alpha 1 alpha 4-dihydroxy-
naphthalene sulphonic acids, and from the aforesaid azo colouring-matters, is
illustrated by the following examples B & C, the parts being by weight.
EXAMPLE B.
30 parts of amido-alpha, alpha, dihydroxynaphthalene-alpha-mono-sulphonic
acid are stirred into 50 parts of hot water, and dissolved by the addition of the
necessary quantity of a 30 per cent. soda-lye. 70 parts of dry sodium sulphide and
66 parts of sulphur are subsequently added. The resulting mixture is then
slowly heated in an iron vessel to about 200 degrees Centigrade, and kept at
this temperature until the mass has become solid. At this stage, the vessel is
closed, and, after the temperature has been raised to from 240 to 250 degrees
Centigrade, heating is continued during from 2 to 3 hours, until test portions
taken from the melt, and dissolved in hot water, yield solutions, the intensity
of which no longer increases. The raw melt thus obtained, when cold, is treated
with hot water in the same manner as described in the foregoing Example A.
The resulting colouring-matter dyes unmordanted cotton violet shades.
EXAMPLE C.
On substituting, in the preceding example, for 30 parts of the amido-alpha,
alpha dihydroxynaphthalene mono-sulphonic acid, 30 parts of the azo dye-
stuff benzene-azo-alpha 1 alpha 4 dihydroxynaphthalene-alpha 2 beta 1 disul-
phonic acid (produced in the usual manner by coupling equimolecular proportions
of diazo benzene and alpha 1 alpha 4-dihydroxynaphthalene-alpha 2 beta 1
disulphonic acid in a solution rendered alkaline by means of a sodium carbonate),
a colouring-matter is finally obtained, which likewise yields violet shades on
unmordanted cotton.
The sodium sulphide and sulphur prescribed in the above examples may be
replaced by other alkaline-sulphide carrying compounds, as hereinbefore defined.

page_text: The proportions and the temperatures given may also be varied within certain
limits.
According to the further researches of my foreign correspondents, the process
hereinbefore illustrated can also be carried out in a more profitable manner, by
which the formation of grey or brown by-products is entirely, or almost entirely
avoided. This effect is attained by heating the aforesaid derivatives of alpha 1
alpha 4 dihydroxynaphthalene sulphonic acids with alkaline-sulphide carrying
compounds, in the presence of zinc, or zinc compounds. By this slight variation
melts are obtained which, when applied to cotton directly dye violet shades fast
against the action of alkalies and light. In this case the above mentioned
extraction of the melt and the further operations are unnecessary.
This modified process is illustrated by the following example. The parts are
by weight.
EXAMPLE D.
30. parts of nitroso-alpha 1 alpha 4-dihydroxynaphthalene-alpha 2 beta 1-disul-
phonic acid are dissolved in 20 parts of water and 82 parts of soda-lye (containing
30 per cent. of Na OH), 20 parts of dry zinc chloride are added, and subsequently
66 parts of dry sodium sulphide and 60 parts of sulphur are stirred into the
resulting mixture. The mass is heated in an iron vessel to 200 degrees Centi-
grade (stirring the while), and heating is continued at this temperature until
the mass has become solid, and can be easily pulverized. At this stage, - the
vessel is closed, and the temperature is raised to 240 degrees Centigrade.
Heating is then continued for from 2 to 3 hours at this temperature.
The blackish mass thus obtained dissolves in water with a violet colour, whereas
a small residue, probably consisting of zinc sulphide, remains undissolved.
It dyes a bright violet on cotton in boiling baths, to which common salt and
sodium carbonate are profitably added. The shades thus obtained are fast against
the action of alkalies and light.
Other violet dyestuffs for cotton are obtained, if other nitroso alpha, alpha
dihydroxynaphthalene di- or mono-sulphonic acids, or if amido alpha, alpha-
dihydroxynaphthalene mono- or di-sulphonic acids, or the azo dye-stuffs derived
from alpha, alpha-dihydroxynaphthalene mono or di-sulphonic acids are used in
place of the nitroso-alpha, alpha,-dihydroxynaphthalene alpha, beta,-disulphonic
acid employed in the last example. The zinc chloride prescribed therein can be
replaced by other zinc compounds, such as zinc sulphate, zinc carbonate, zinc
oxide, or the like, or also by metallic zinc, which is profitably used in the form
of zinc dust.
The proportions and the temperatures mentioned in the Example D can be
varied within certain limits; other alkaline-sulphide carrying compounds can be
used in place of sodium sulphide and sulphur. In all cases, melts are obtained
which directly yield on cotton violet shades fast against the action of alkalies
and light.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed (as communicated to
me from abroad), I declare that what I claim is;
1. The process for producing violet cotton dye-stuffs from the products obtain-
able by subjecting, at elevated temperatures, to the action of alkaline-sulphide
carrying compounds, amido alpha, alpha-dihydroxynaphthalene sulphonic acids,
nitroso alpha, alpha,-dihydroxynaphthalene sulphonic acids, or the azo colouring-
matters resulting from the combination of diazo compounds with alpha, alpha-
dihydroxynaphthalene sulphonic acids, which process consists in repeatedly
extracting the above defined products with hot water, until the readily soluble
component part thereof has been wholly dissolved out, filtering the solutions thus
formed, and finally isolating the dye-stuffs from the joint filtrates.
2. The production of violet cotton dye-stuffs from the following alpha, alpha-

page_text: dihydroxynaphthalene sulphonic derivatives, viz., amido-alpha,-alpha-dihydroxy-
naphthalene sulphonic acids, nitroso-alpha,-alpha-dihydroxynaphthalene sul-
phonic acids, or the azo colouring-matters resulting from the combination of
diazo compounds with alpha, alpha-dihydroxynaphthalene sulphonic acids, which
process consists in subjecting the said alpha, alpha-dihydroxynaphthalene
derivatives, in the presence of zinc or zinc compounds, to the action of alkaline
sulphide carrying compounds, at elevated temperatures.
3. As articles of manufacture, the new violet cotton dye-stuffs obtainable by the
process hereinbefore defined.
Dated this 30th day of November 1899.
NEWTON & SON,
Agents for the Applicant.