The Manufacture or Production of New Colouring Matters.
Year: 1897

page_text: Date of Application, 7th Aug., 1897
Complete Spacitionation Loft fot Juns 1000 Accented 2nd lily 1000
The Manufacture or Production of New Colouring Matters.
We, IVAN LEVINSTEIN and LEVINSTEIN LIMITED, both of Minshull Street,
Manchester, in the County of Lancester, Chemical Manufacturers, do hereby
declare the nature of this invention to be as follows:
We have discovered that if para-nitro-toluene ortho-sulphonic acid is suitably
heated in presence of a caustic alkali, with hypochlorites or hypobromites, it is
converted into a new body which is not only of scientific interest but also of high
technical value.
If this new product is partially reduced with weak reducing agents such as
ferrous sulphate and ammonia, grape sugar and alkali, alkaline sulphides, and
similar reducing agents, direct colouring matters are formed varying from yellow
to red and we have so far found that duration of action, also quantity of reducing
agents, influence the shade of colour obtained.
If this new product is reduced by means of strong reducing agents, as for
example, by means of tin and acids, of stannous chloride and acids, of zinc and
acids, of zinc dust and alkalies, of iron and acids, and the like, an amido body is
formed which, when treated with nitrous acid gives a diazo substance which com-
bines with amines or with phenols, forming very valuable direct colouring matters
differing in colour from yellow to black.
We have further discovered that by heating our new substance (obtained as
herein before described by treating paranitrotoluene ortho-sulphonic acid with
hypochlorites or hypobromites), in presence of caustic alkali with diamines such
for example as benzidine, alpha, alpha, naphthylenediamine beta, sulphonic acid,
other new colouring matters are produced which dye cotton direct, from yellow
to red. These new colouring matters may then be diazotised, either in substance
or on the fibre, and either coupled or developed with suitable amines or phenols
and a further new range of colouring matters is thus obtained which produce
much darker tints varying from brown to violet and black.
W. E. HEYS & SON,
Agents for the Applicants.
The Manufacture or Froaаснов оf New colouring мастегв.
We, IVAN LEVINSTEIN and LEVINSTEIN LIMITED, both of Minshull Street,
Manchester, in the County of Lancester, Chemical Manufacturers, do hereby
[Price 8d.]

page_text: declare the nature of this invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
We have found that if paranitrotoluene orthosulphonic acid or its salts are
oxidised under suitable conditions hereinafter described, with hypochlorites or
hypobromites, the acid is converted into a new acid which, so far as has been
ascertained by present research, appears to have the constitution of a dinitro-
stilbene disulphonic acid which is of great technical value for use in the produc-
tion of colouring matters.
To effect the oxidation of the nitrotoluene sulphonic acid we may proceed as
follows:
EXAMPLE I.
240 kilos of the sodium salt of paranitrotoluene ortho-sulphonic acid is dis-
solved in about 8 times its weight of hot water. Whilst the solution is kept
continually stirred, 70 litres of sodium hypochlorite solution containing 150 grams
of hypochlorite and 30 grams of caustic soda per litre, is allowed to run in slowly.
During the reaction, the temperature is preferably kept at from 70 to 80 deg. C.
As soon as a sample of the mixture, when acidified, no longer evolves chlorine, it
is neutralised with hydrochloric or other suitable acid and allowed to cool. The
greater part of the dinitrostilbene disulphonic acid crystallises out as the neutral
sodium salt in the form of beautiful pale yellow leaflets which are easily soluble]
in hot water but sparingly soluble in cold water. The remaining portion of
the dinitrostilbene disulphonic acid may be separated out by saturating the
mother liquor with common salt, potassium chloride, or otherwise. For general
purposes it is however not necessary to separate the acid. When the oxidation
is finished, the liquid containing the whole of the dinitrostilbene disulphonic
acid salt may be used directly for the production of colouring matters, or the acid
may be reduced to diamidostilbene disulphonic acid as hereinafter described.
If the dinitrostilbene disulphonic acid or its salts is partially reduced with
weak reducing agents, such as ferrous sulphate and ammonia, grape sugar and
alkali, alkaline sulphides, and the like, direct colouring matters are formed vary-
ing in shade from yellow to orange-red, which shade, appears to be influenced
by the duration of the reaction and by the quantity of the reducing agent
employed.
For the production of these colouring matters we may, for instance, proceed
as follows:-
EXAMPLE II.
PRODUCTION OF AN ORANGE-RED COLOURING MATTER.
47'4 kilos. of sodium dinitrostilbene disulphonate is dissolved in hot water,
50 litres of 30 per cent. caustic soda solution are added, and during the resulting
reaction, the temperature of the mixture is preferably kept at about 60 .deg. C
Then, whilst the mixture is kept continually stirred, a solution containing 300
kilos of invert sugar in hot water is allowed to run in slowly. The liquid becomes
dark red, and after some time, the colouring matter begins to separate out. The
reduction is complete when, on further heating, the intensity of the colour does
not increase: The colouring matter is then salted out, filtered off, pressed and
dried. It dissolves in concentrated sulphuric acid with a pure blue colour which,
on dilution with water, changes to green. It has, probably, the constitution of
an azostilbene disulphonic acid, and dyes unmordanted cotton a pure orange-red.
Since, as herein before described, the shade of the resulting colouring matter
is influenced by the conditions of the reaction and by the quantity of the reducing
agent employed, it will be evident that in these respects we do not limit ourselves
to the precise conditions of the reaction nor to the quantity of the reducing agent
set forth in this example.

page_text: A similar colouring matter may be obtained if the sodium dinitrostilbene disul.
phonate is reduced with a sufficient amount of sodium sulphide, or if we proceed
as follows;
-
EXAMPLE III.
A solution consisting of 240 kilos of sodium dinitrostilbene disulphonate dis-
solved in 300 litres of hot water, is digested with 500 kilos of caustic soda solu-
tion 40° Bé, and 50 litres of ethyl alcohol at a temperature of about 70° C., for
one or two hours. The mass becomes an intense orange-red. When the reaction
is complete, the excess of caustic soda is neutralised by hydrochloric or other suit-
able acid. On cooling, the colouring matter separates out as an orange-red
crystalline precipitate, which is filtered off, pressed and dried It dyes vegetable
fibres orange-red
If, again, instead of the 300 kilos of invert sugar of Example II, or the 22 to 24
kilos of Example IV, only 15'0 kilos are used, the process being otherwise con-
ducted as described under Example II, a colouring matter results which dyes
unmordanted cotton a bright yellow, fast to alkali.
As already stated, it is not necessary for the production of these colouring
matters that isolated dinitrostilbene disulphonic acid should be used. It will
suffice to employ the liquid of oxidation produced as described under Example I,
with the corresponding proportions of the specified reducing agents.
If the dinitrostilbene disulphonic acid be completely reduced by means of strong
reducing agents, as for example by means of tin and acids, stannous chloride and
acids, zinc and acids, zine dust and alkali, iron and acids, and the like, a diamido di-
sulphonic acid is formed which, when treated with nitrous acid, gives a tetrazo
compound which combines with amines or phenols, forming very valuable colour-
ing matters ranging in shade from yellow to black. This reduction of the dinitro-
stilbene disulphonic acid to the diamidostilbene disulphonic acid may, for
instance, be carried out as follows:-
EXAMPLE VI.
474 kilos of sodium dinitrostilbene disulphonate is gradually added to a mix-
ture of 1350 kilos of stannous chloride and 1400 kilos of 30 per cent. hydrochloric
acid, and the whole mass is heated to boiling. When the reduction is completed,
the diamidostilbene disulphonic acid separates out in the form of white insoluble
needles. By filtration and washing with water, it can be obtained in an almost
chemically pure state.
In the production of the diamidostilbene disulphonic acid, it is also unnecessary
to separate the dinitrostilbene disulphonic acid from the mather liquor. When
the oxidation of the paranitrotoluene orthosulphonic acid is complete, the mix-
ture may be strongly acidified with hydrochloric or other suitable acid. Then,
by the addition of tin, tin protochloride, zinc, or the like, to the boiling mixture,
the acid is reduced to the diamidostilbene disulphonic which appears to be iden-
tical with the acid of Bender and Schulz (Berichte of the German Chemical Society
Vol. XIX, p. 3237).

page_text: EXAMPLE VII.
PRODUCTION OF COLOURING MATTERS FROM DIAMIDOSTILBENE DISULPHONIC ACID.
370 kilos of diamidostilbene disulphonic acid is dissolved in a solution of
sodium carbonate or of other suitable alkali; the solution is cooled with ice;
acidified with 55'0 kilos of 30 per cent. hydrochloric acid, and then tetrazotised
by the addition of a solution containing 144 kilos of sodium nitrite in the usual
manner. The resulting tetrazo body is a yellowish brown crystalline powder
which is almost insoluble in water. If this product is introduced into a solution
containing 500 kuos of amidonaphthol sulphonic acid-gamma, and the mixture
be kept alkaline during the reaction with sodium carbonate, a colouring matter
results which dyes unmordanted vegetable fibres a violet-black colour. It may
be diazotised on the fibre and be developed with suitable amines or phenols such
for example as betanaphthol, resorcin, metatolylenediamine, and the like, whereby
blueish black to greenish black shades are produced which are fast to milling.
We have further found that by heating the dinitrostilbene disulphonic acid
or its salts in presence of caustic alkalies with amines diamines or amidophenols
such for example as benzidine paraphenylenediamine metatolylenediamine alpha
alpha, naphthylenediamine parasulphonic acid and the like, other new colouring
matters are produced which die cotton direct in shades varying from yellow to red.
Some of these colouring matters may be diazotised either in substance or on the fibre
and be either coupled or developed with suitable amines or phenols, a further
range of colouring matters being thus produced having much darker tints. vary-
ing from brown to violet and black.
In the following examples we describe processes for the production of these
further colouring matters, but it will be obvious that these are typical only and
might be greatly extended. Thus, differing shades are produced if the specified
proportions are varied or the specified conditions of the reactions are modified,
without however affecting the technical properties of the resulting colouring
matters apart from their shades or tints. We desire it therefore to be understood
that we do not limit ourselves to the precise proportions and conditions herein-
after specified.
EXAMPLE VIII.
240 kilos of sodium dinitrostilbene disulphonate are dissolved in about 300
litres of hot water; 600 kilos of caustic soda solution 40° Be.; and 18.0 kilos
of paraphenylenediamine hydrochloride are added, and the mixture is heated to
boiling for from 2 to 3 hours. The mass soon becomes intensely orange-red and
the colouring matter partly separates out during the reaction. When the con-
densation is complete, the excess of caustic soda is neutralised by means of
hydrochloric or other suitable acid, and the colouring matter is salted out, filtered,
pressed and dried. It dyes unmordanted cotton orange, and may be diazotised
and developed on the fibre with suitable developers, producing thus dark brown
to violet-black shades.
EXAMPLE IX.
If, instead of the 180 kilos of paraphenylenediamine hydrochloride used in
the last preceding example, 90 kilos of benzidine are condensed with 240 kilos
of sodium dinitrostilbene disulphonate, and the reaction is carried out as described
in that example, a colouring matter results which dyes unmordanted fibres orange-
yellow. If this colour diazotised and developed on the fibre, with amines
diamines and phenols, dark brown to black tints are obtained.

page_text: are added, and the whole is digested at about 70° to 80° C., for from 2 to 3 hours.
When the condensation is complete, the excess of caustic soda is neutralised and
the colouring matter is salted out, filtered, pressed and dried. It dyes unmor-
danted cotton yellow. Analogous colouring matters are obtained if, instead of
paranitraniline, its isomers or homologues, or nitronaphthylamines are condensed
with the dinitrostilbene disulphonic acid.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed, we declare that what
we claim is:-
-
1. The herein before described process for the production of yellow to orange-red
direct colouring matters, which consists in the oxidation of paranitrotoluene
ortho-sulphonic acid or its salts by hypochlorites or hypobromites, in the presence
of a caustic alkali and in reducing the thus obtained dinitrostilbene disulphonic
acid by means of weak reducing agents substantially as set forth.
2. The hereinbefore described process for the production of yellow to orange-
red direct colouring matters which consists in acting upon dinitrostilbene disul-
phonic acid in the presence of a caustic alkali by means of amines diamines nitra-
mines or amidophenols, substantially as set forth.
3. The hereinbefore described process for the production of direct colouring
matters which consists in (a), the complete reduction of dinitrostilbene disulphonic
acid and (b), tetrazotising the diamidostilbene disulphonic acid thus produced and in
combining the resulting tetrazo body with amines diamines phenols amidophenols
and dioxy bodies both of the benzene and of the naphthalene series as well as
with their known sulphonic and carboxylic acids, substantially as set forth.
בד
1000
Dated this Sist day of May A.D. 1998.
W. E. HEYS & SON,
Agents for the Applicants.