Acids and of Dye Stuffs therefrom.
Year: 1886

page_text: Date of Application, 9th Oct., 1886.
Complete Left, 7th July, 1887.
Complete Accepted, 9th Aug., 1887,
Acids and of Dye Stuffs therefrom.
I, GEORGE PITT of Sutton in the County of Surrey, Gentleman do hereby declare
the nature of this invention to be as follows :-
Ebert and Merz have stated in the Berichte der Deutschen Chemischen Gesellschaft
Vol. IX page 612 that when a naphtaline-disulphonic acid is heated together with an
alkali, both sulpho-groups are simultaneously taken out, and that exclusively dioxy-
naphtaline is formed.
I have however found that when the reaction is stopped at a certain stage a new
uniform naphtol-monosulphonic acid is obtained which shows sharply defined differences
from all other known acids. In order to obtain this acid I proceed for instance as
follows
10 kilos of a naphtaline disulphonate of soda I mix with 40 kilos of 50% caustic
soda and heat the mixture to about 200° C. until it has become quite consistent and
an acidulated sample yields to ether traces of dioxynaphtaline or until the quantity
of dye stuff formed by a sample of certain weight with diazoxylol remains stationary.
The melt I dissolve in water, acidulate it with muriatic acid and by boiling cause the
sulphurous acid to escape. The solution thus obtained can be used directly for the
production of azo-dyes. When the solution is evaporated to about 150 litres and
cooled down, the sodium-salt will almost entirely separate by crystallization.
In this method the quantity of alkali and the temperature may vary considerably,
the caustic soda may be replaced by hydrate of potassium and the naphtaline sulpho-
nate of soda by other salts of the same acid. In any case the operation is to be
interrupted as stated above.
The alkaline solution of the salts of the new sulphonic acid has a pure blue
fluorescence; chloride of iron produces in neutral solutions a dark blue colouring,

page_text: By the action of nitrous acid upon the new acid, a nitroso-compound is obtained, which
yields a green dye stuff by the method described in the British Patent No. 226984.
With all known diazo-compounds the new acid combines in alkaline solution, even
when diluted. I especially mention the colours produced by the azo-derivatives of
aniline, toluidine, xylidine, a and ẞ naphtylamine, amidoazobenzole, amidoazotoluole,
amidoazoxylole, amidoazonaphtaline, by the nitranilines, the nitrotoluidines, by benzi-
dine, tolidine, dianisidine and by the sulphonic acids of the above named bases. The
shades of these dyestuffs are bluer than those of the corresponding dyestuffs obtained
from the Schaeffer-monosulphonic acid of naphtol. The new acid has a most
characteristical action upon a diazonaphtaline producing a blueish precipitate which
dyes wool a claret-red, and upon diazobenzole producing a difficultly soluble orange
having an eminent tendency to crystallize.
If the new naphtoimonosulphonic acid is heated with ammonia, the NH, group
takes the place of the OH group and a new ẞ naphtylamine-monosulphonic acid is
obtained; for instance:
50 kilos of naphtolmonosulphonate of soda are heated in an autoclave, together
with 100 kilos of 20% ammonia during 6 hours to 250° C. When the product of the
reaction is acidulated, the acid separates in shining crystals. Or one may start from
the naphtaline-disulphonic acid and heat the same with Na OH and NH, and
proceed as above described.
The solutions of the salts of the new acid show a violet fluorescence, the soda-salt is
difficultly soluble in water and crystallizes in needles, when strongly acidulated the
sulphonic acid separates in crystals and gives by addition of nitrite of soda a clear
solution of the diazocompound.
This diazocompound can be combined with the above named amines, phenoles and
their sulphonic acids in the known manner so yielding a series of dyestuffs, of which
for instance the dyestuff formed with the so-called acid R and a naphtolmonosulphonic
acid dyes a blueish red and the dyestuff formed with a naphtylamine gives a diazoazo-
compound by the action of nitrous acid and can be transformed into black dyestuffs
by the process described in the British Patent No. 921485
Besides these, a series of most valuable dyestuffs are obtained from the new naphtyl-
amine-sulphonic acid by the reactions of the above named diazocompounds upon the
same. They resist acids and are in shade yellower than the analogous hydroxyl-
compounds. An exception is the dyestuff obtained with paranitrodiazobenzole, which
dyes a cherry-red. Tetrazodiphenyl produces a brownish-violet precipitate, which
dissolves with a red colour on prolonged standing of the alkaline or weakly acidulated
solution; the dyestuff thus formed dyes cotton in alkaline bath a red shade, the dyeing
resists weak acids. If the brownish-violet precipitate is filtered and put into an
alkaline solution of another amine or phenole or their sulphonic acids, mixed tetrazo-
dyestuffs are formed. Tolidine and dianisidine act in a manner similar to benzidine.
Dated this 9th day of October 1886.
CARPMAEL & Co.,
Agents for the Applicant.

page_text: The Manufacture of New Naphtol and Naphtylamine Monosulphonic
Acids and of Dye Stuffs therefrom.
I, GEORGE PITT of Sutton in the County of Surrey, Gentleman, (a communica-
tion to me from abroad by Leopold Cassella and Company of Frankfort-on-Main in
the Empire of Germany, Manufacturers) do hereby declare the nature of this inven-
tion and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement :-
Ebert and Merz have stated in the Berichte der Deutschen Chemischen Gesellschaft
vol. IX, page 612 that when a naphtaline disulphonic acid is heated together with an
alkali, both sulpho groups are simultaneously taken out, and that exclusively dioxy-
naphtaline is formed.
It has however been found by Dr. Arthur Weinberg, Chemist to Leopold Cassella
and Company that at a certain stage of this reaction a new uniform naphtol-mono-
sulphonic acid is formed which shows sharply defined differences from all other known
acids. In order to obtain this acid which Dr. Weinberg has named ẞ naphtolmono-
sulphonic acid F proceed for instance as follows:-
10 kilos of a naphtaline disulphonate of soda mix with 40 kilos of 50% caustic soda
and heat the mixture to about 200° C. until it has become quite consistent and an
acidulated sample, yields to ether traces of dioxynaphtaline or until the quantity of
dye stuff formed by a sample of certain weight with diazoxylol remains stationary.
Then dissolve the melt in water, acidulate it with muriatic acid and by boiling cause
the sulphurous acid to escape. The solution thus obtained can be directly used for the
production of azo-dyes. When the solution is evaporated to about 150 litres and
cooled down, the sodium salt will almost entirely separate by crystallization.
In this method the quantity of alkali and the temperature may vary considerably,
the caustic soda may be replaced by hydrate of potassium and the naphtaline
sulphonate of soda by other salts of the same acid. In any case the operation is to
be interrupted as stated above.
It is evident that between the moment when the transformation into dioxynaphtaline
would be completed and the moment when exclusively the new acid F is present both
substances are present in varying quantities. If the operation is interrupted during
this interval, it will be easy to separate the two bodies. This may be effected either
by precipitation of the dioxy compound from the aqueous solution of the sodium salt
by means of an acid and filtration or by exhausting the acidulated aqueous solution of
the sodium salt with ether or by other means of like effect.
The formation of the dioxynaphtaline is best avoided by working only with 2 mole-
cules of a caustic alkali upon 1 molecule of a naphtaline disulphonate salt and heating
during 16 hours in an autoclave at 250° C.
The alkaline solution of the salts of the new sulphonic acid has a pure blue
fluorescence. Chloride of iron produces in neutral solutions a dark blue coloring.

page_text: By the action of nitrous acid upon the new acid, a nitroso-compound is obtained,
which yields a green dye stuff by the method described in the British Patent
No. 2269. With all known diazo-compounds the new acid combines in alkaline
solution, even when diluted, I especially mention the colors produced by the azo-
derivatives of aniline, toluidine, xylidine, a and naphtylamine, amidoazobenzol,
amidoazotoluol, amidoazoxylol, amidoazonaphtaline, by the nitranilines, the nitro-
toluidines, by benzidine tolidine, dianisidine and by the sulphonic acids of the above
named bases. The shades of these dye stuffs are bluer than those of the corresponding
dye-stuffs obtained from the Schaeffer-monosulphonic acid of ẞ naphtol. The new
acid has a most characteristical action upon a diazonaphtaline producing a blueish
precipitate which dyes wool a claret-red, and upon diazobenzol producing a difficultly
soluble orange having an eminent tendency to crystallize. If the new naphtolmono-
sulphonic acid heated with ammonia, the NH, group takes the place of the OH
group and a new ẞ naphtylamine-monosulphonic acid which Dr. Weinberg has named
naphtylamine-monosulphonic acid F is obtained, for instance:
50 kilos of naphtolmonosulphonate of soda, are heated in an autoclave, together
with 100 kilos of 20% ammonia during 6 hours to 250° C. When the product of
the reaction is acidulated, the acid separates in shining crystals or one may start from
the naphtaline-disulphonic acid and heat the same with Na OH and NH, and
proceed as above described.
The solutions of the salts of the new acid show a violet fluorescence, the soda salt
is difficultly soluble in water and crystallizes in needles, when strongly acidulated the
sulphonic acid separates in crystals and gives by addition of nitrite of soda a clear
solution of the diazo-compound.
This diazo-compound can be combined with the above named amines, phenols and
their sulphonic acids in the known manner so yielding a series of dye stuffs, of which
for instance the dye stuff formed with the so-called acid R and a naphtolmonosulphonic
acid dyes a blueish red and the dye stuff formed with a naphtylamine gives a diazoazo
compound by the action of nitrous acid and can be transformed into black dye stuffs
by the process described in the British Patent No. 9214³.
Besides these, a series of most valuable dye stuffs are obtained from the new
naphtylamine-sulphonic acid by the reactions of the above-named diazo compounds
upon the same. They resist acids and are in shade yellower than the analogous
hydroxyl compounds.
An exception is the dye stuff obtained with paranitrodiazobenzol which dyes a
cherry red. Tetrazodiphenyle produces a brownish-violet precipitate, which dissolves
with a red color on prolonged standing of the alkaline or weakly acidulated solution.
The dye stuff thus formed dyes cotton in alkaline bath a red shade, the dyeing resists
weak acids.
If the brownish-violet precipitate is filtered and put into an alkaline solution of
another amine or phenol or their sulphonic acids, mixed tetrazo dye stuffs are formed.
Tolidine and dianisidine act in a manner similar to benzidine. In producing these
dye stuffs one equivalent of the tetrazo-compound of benzidine, tolidine or dianisidine
should be brought to react on one equivalent of either the new naphtol or the naphtyl-
amine sulphonic acid and one equivalent of another sulphonic acid of a Phenol or an
amine or one equivalent of a not sulphonated Phenol or amine.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is :-
First. The process for producing the ẞ naphtolmonosulphonic acid F substantially
as herein described, by heating a naphtaline disulphonate salts with caustic alkalies.
Second. The process for producing ẞ naphtylaminemonosulphonic acid F consisting
in the transformation of the ẞ naphtolmonosulphonic acid F by heating it with
ammonia substantially as herein described.
Third. As a new manufacture the ẞ naphtolmonosulphonic acid F.
Fourth. As a new manufacture the ẞ naphtylaminemonosulphonic acid F.
Fifth.—The preparation substantially as described of the azo dye stuffs herein

page_text: described by the reaction of ẞ naphtolmonosulphonic acid F upon the diazo-compounds
from aniline, toluidine, xylidine, amidoazobenzol, amidoazoxylol, amidoazotoluol,
a and ẞ naphtylamine, amidoazonaphtaline, nitraniline, benzidine, tolidine, dianisidine
and the sulpho acids of the named bases.
Sixth. The preparation substantially as described of the azo dye stuffs herein
described by the reaction of ẞ naphtylaminemonosulphonic acid F upon the diazo
compounds named in the fifth claim.
Seventh. The preparation substantially as described of the mixed azo dye stuffs
herein described by the reaction of the tetrazo compounds of benzidine, tolidine,
dianisidine with the new naphtol or the naphtylamine sulphonic acid and another
amine, phenol or a sulpho acid thereof.
Eighth. As new manufactures the novel azo dye stuffs herein described.