Improvements in the Manufacture of Alpha Naphthol Sulpho Acids and Dioxynaphthalene Sulpho Acids and of Dyestuff's therefrom.
Year: 1890

page_text: Date of Application, 4th Mar., 1890
Complete Specification Left, 4th Dec.. 1890-Accepted, 10th Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Alpha Naphthol Sulpho
Acids and Dioxynaphthalene Sulpho Acids and of Dyestuff's
therefrom.
I, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of Middlesex
Patent Agent do hereby declare the nature of this invention (which has been com-
municated to me from abroad by The Farbenfabriken vormals Friedrich Bayer & Co.
of Elberfeld in the Empire of Germany) to be as follows:-
When Armstrong's alpha napthol mono sulpho acid is heated with a sulphurising
asent such as from 2 to 3 parts of 66 per cent. acid or mono hydratic or weak fuming
acid or with mono chlor hydrin at the temperature of a water bath a new alpha
naphthol disulpho acid is formed which differs from the known alpha naphthol disulpho
aci is described in the Specifications to the German Patents Nos. 40571 and 45776
inasmuch as it does not give a nitroso compound as the others do.
'
:―
To obtain this new acid my foreign correspondents proceed as follows:-
The Armstrong's alpha naphthol mono sulpho acid is dissolved in 3 parts of 66 per
cent. acid, the temperature of the melt is slowly raised to about 90 degrees Cent.,
or to the temperature of a water bath and maintained at this temperature until a
change in the fluoresence indicates that the reaction is ended. The melt is treated in
the usual way, limed, converted into the soda salt and the new alpha naphthol disulpho
acid is obtained in the form of its soda salt crystallizing in the form of solid 'spikes
on concentrating the filtrate and cooling.
When Piria alpha naphthol mono sulpho acid is treated with sulphurising agents a
naphthyl sulphuric acid is formed in the first instance which is converted at a high
temperature only into its isomer a new naphthol disulpho acid. The process of the
manufacture of this new product is conducted as follows:-
One part of alpha naphthol mono sulpho acid is dissolved in three parts of fuming
acid and the melt is slowly heated to the temperature of a water bath.
At a temperature of 75 degrees Cent. the whole mass stiffens into a thick paste of
separated naphthyl sulphuric acid; on further raising the temperature the melt again
becomes thin and at about 90 degrees Cent. is in the form of a clear solution.
To isolate the new naphthol disulpho acid it is treated with lime converted into the
soda salt and the acid soda salt is precipitated in the form of jelly from the acidulated
solutions of the concentrated filtrate saturated with common salt. This new alpha
naphthol disulpho acid also gives no nitroso compounds, it couples with difficulty with
diazo compounds contrarily to the naphthol disulpho acids heretofore known
(especially the above mentioned new Armstrong alpha naphthol disulpho acid). By
subjecting these two new acids to the action of nitric acid there is obtained with the
first a mono nitro product, a mono nitro naphthol mono sulpho acid with the second
on the contrary a dinitro product, a dinitro naphthol mono sulpho acid. This product
dyes with still purer tones than the product known as naphthol yellow S the product
of the reaction of nitric acid upon alpha naphthol trisulpho acid.
A new alpha naphthol trisulpho acid is obtained by treating with fuming acid the
naphthsultone or the naphthol disulpho acid S described in the Specification to the
German Patent No. 40571. In order to obtain the new alpha naphthol trisulpho acid
the process is conducted as follows according as the naphthsultone or the disulpho acid
is employed.
The said acids are allowed to stand with 5 parts or 2 parts of fuming acid con-
taining 25 per cent. of anhydride at the ordinary temperature until a sample ceases to
form colouring matter with diazo compounds this taking place under the above
mentioned conditions usually after standing about 12 hours.

page_text: The sulphurising is completed more quickly at elevated temperatures but not at
temperatures of over 100 degrees Cent. or with the employment of stronger fuming
acid. The melt is poured out on to ice and converted into the lime salt and soda salt
in the usual manner.
After concentrating the liquid and acidulating with hydrochloric acid, the acid soda
salt of the new naphthol trisulpho acid is completely precipitated out of the hot
solution in the form of a heavy sandy powder on the addition of common salt. Its
action in respect of diazo compounds in which it does not form any colouring matter
is highly characteristic of this acid. The neutral soda salt dissolves very readily in
water with a green fluorescence. By the action of nitric acid a nitro naphthol sulpho
acid known as naphthol yellow R S is obtained.
The new naphthol sulpho acids hereinbefore described can be converted into new
dioxynaphthalene sulpho acids in the usual manner that is to say by treatment with
caustic alkalies at elevated temperatures in either open or closed vessels.
To obtain the new alpha dioxy naphthalene mono sulpho acids from the hereinbefore
described new Piria and Armstrong alpha naphthol disulpho acids the latter are
melted with three parts of caustic soda at about 250 degrees Cent. until a sample
shows a disappearance of the fluoresence and emits a strong odour of sulphurous acid
when acidulated.
°
The Armstrong alpha naphthol disulpho acid produces a dioxynaphthalene mono
sulpho acid which crystallises out of concentrated solutions of common salt in the
form of fine shining leaves of acid soda salt containing no water of crystallization.
With chloride of iron this acid produces an unstable blue green solution. From one
to two drops of solution of chloride of lime produce a red brown colour which is
unchanged by an excess of chloride of lime solution.
The Piria alpha naphthol disulpho acid leads to a dioxynaphthalene mono sulpho
acid which crystallises out as an acid soda salt from acid saturated solutions of
common salt in fine white mucilaginous needles. With chloride of iron it produces a
permanent blue green solution, or with a chloride of lime solution a blue red solution
which by an excess passing through wine yellow can be rendered colourless.
When the new naphthol trisulpho acid hereinbefore described is melted a new
dioxynaphthalene disulpho acid is obtained.
The conversion may be conducted in open or closed vessels with or without the
employment of pressure. In the former case concentrated caustic alkali must be
employed but in the latter case it may be diluted. The process may be conducted
as follows, for example:
One part of trisulpho acid is heated under pressure to about 250 degrees Cent.
for about 16 hours with one part of a 350 per cent. lye.
With a concentrated soda lye of 200 degrees Cent. in an open vessel, the reaction
is almost instantly completed. The completion of the reaction is known by the
disappearance of the fluorescence or by the formation of colouring matter with diazo
compounds. On acidulating the melt in solution the dioxynaphthalene disulpho acid
formed crystallises after saturation with common salt out of the hot solution in white
colourless needles of acid soda salt.
These new naphthol disulpho acids and especially the Armstrong acid as well as the
dioxynaphthalene mono and disulpho acids are very well adapted for the manufacture
of colouring matters. They unite in diazo as well as in tetrazo compounds and the
new dioxynaphthalene sulpho acid colouring matters thus obtained are distinguished
by their blue redness with diazo compounds, bluer shades being obtained with tetrazo
compounds.
The Armstrong dioxynaphthalene mono sulpho acid produces with the diazo
compounds of aniline, toluidine, xylidine, anisidine, alpha and beta naphthylamine
very beautiful fuchsine red to violet colouring matters. Other shades are obtained
with the new dioxynaphthalene disulpho acid, these colouring matters are somewhat
more soluble and of a bluer color. Blue black colouring matters are obtained when
the diazo compounds are employed of those amido azo colouring matters which are
produced by the combination of any diazo compounds with alpha amido naphthol

page_text: ether, alpha naphthylamine or alpha amido beta naphthol ether by further diazotising
and then reacting on naphthol disulpho acids and on dioxynaphthalene mono and
disulpho acids.
Direct dyeing coloring matters are obtained when the aforesaid acids are allowed
to act on the tetrazo compound of a diamine, such as benzidine, tolidine, diamido,
phenyl, tolyl, diamido, stilbene, dianisidine monoethoxybenzidine, diamido mono
ethoxy phenyl tolyl, or their sulpho and carbon acids.
According to another method, one molecule of the tetrazo compound is caused to
act on two molecules. of the new acid. A valuable greenish blue, which with the
employment of tetrazo diphenol ether acquires a brighter green tinge is produced by
the action of one molecule for example of tetrazo diphenyl upon Armstrong's dioxy-
naphthalene mono-sulpho acid.
As well understood in the production of direct dyeing colouring matters, the com-
bination of the dyestuff components with tetrazo compounds may also be effected by
first causing one inolecule of the tetrazo compound to act upon one molecule of the
dyestuff component and then allowing the intermediate product formed to act upon
any other dyestuff components for the production of the colouring matter itself.
This property of the tetrazo-compounds can be utilized in the present case, also, an
intermediate product being produced in the first place with the Armstrong alpha
naphthol disulpho acid, and this being caused to act in turn upon any amine or
phenol, or the sulpho and carbon acids thereof. With the dioxynaphthalene sulpho
acids, on the other hand it is preferable to produce the intermediate product in the
first place with another amide or phenol, or the sulpho or carbon acid thereof and
then to allow it to react on the new dioxynaphthalene sulpho acid obtained according
to this invention. This somewhat different method of proceeding is rendered
preferable owing to the property possessed by all dioxynaphthalene sulpho acids
more or less of reacting with 2 molecules of a diazo compound and of not smoothly
or regularly producing the intermediate products.
Colouring matters dyeing cotton directly black are obtained when the aforesaid
tetrazo compounds or their sulpho or carbon acids are combined in the first place with
one or with two molecules of alpha naphthylamine or alpha amido naphthol ether or
alpha amido beta naphthol ether the compound obtained being further diazotized
and the new tetrazo compounds allowed to act upon the aforesaid new dyestuff
components.
Direct dyeing coloring matters of from blue to blue black shades are derived from
paraphenylene diamine by diazotising acetyl paraphenylene diamine coupling with
alpha-naphthylamine, again diazotising and acting on the aforesaid dioxynaphthalene
sulpho acids, the acetyl group splitting off, again diazotising and combining with
amides, phenols and the like in the usual manner.
Useful coloring matters likewise dyeing cotton in an alkaline bath are also obtained
when the diazo-compounds of dehydro thio toluidine and dehydro thio xylidine or
their sulpho acids are caused to react upon the new acids. These thio bases are
obtained by heating para toluidine and meta xylidine with sulphur.
The known process is employed for the production of all these azo colouring
matters and consists in allowing the diazo or tetrazo combinations to run into
solutions of the new acid maintained alkaline to the end with soda.
Azo colouring matters dyeing wool black in an acid bath are obtained by the
action of the diazo compounds of any amine, or its mono and disulpho acids upon
alpha naphthylamine or alpha amido beta naphthol ether, the amido azo colouring
matter obtained, being further diazotized and allowed to act upon the sulpho acids.
Direct dyeing blue azo colouring matter is obtained by the action of the para
diazo acet anilide or alpha diazo naphthalene, azo acet anilide upon the sulpho acids
herein before referred to splitting off the acetyl group further diazotising and acting
on one molecule of a phenol, a dioxynaphthalene and the sulpho acids thereof.
Dated this 3rd day of March 1890.

page_text: COMPLETE SPECIFICATION.
Improvements in the Manufacture of Alpha Naphthol Sulpho
Acids and Dioxynaphthalene Sulpho Acids and of Dyestuffs
therefrom.
I BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of Middlesex,
Patent Agent, do hereby declare the nature of this invention (which has been com-
municated to me from abroad by The Farbenfabriken vorm. Friedr. Bayer & Co. of
Elberfeld in the Empire of Germany) and in what manner the same is to be per
formed to be particularly described and ascertained in and by the following
statement :-
.
=
When alpha naphthol mono sulpho acid (OH SO, H: 15) is heated with a
sulphonating agent such as from 2 to 3 parts sulphuric acid of 66 degrees Beaumé or
mono hydrated or weak fuming acid or with monochlorhydrin at the temperature of a
water bath a new alpha naphthol disulpho acid is formed which differs from the
known alpho naphthol disulpho acids described in the Specifications to the German
Patents Nos. 40571 and 45776 inasmuch as it does not give a nitroso compound as the
others do.
To obtain this new acid my foreign correspondents proceed as follows:-
The alpha naphthol mono sulpho acid is dissolved in 3 parts of sulphuric acid of
66 degrees Beaumé ; the temperature of the melt is slowly raised to about 90 degrees
Centigrade, the temperature of a water bath, and maintained at this temperature until
a change in the fluorescence indicates that the reaction is ended. The melt is treated
in the usual way, limed and converted into the soda salt. The soda salt of the new
alpha naphthol disulpho acid crystallizes out in solid spikes on concentrating the
filtrate and cooling.
When the alpha naphthol mono sulpho acid (OH SO, H = 1:4) is treated with
sulphonating agents a naphthyl sulphuric acid is formed in the first instance
which is converted at a high temperature into the sulphuric acid ether of a
naphthol disulpho acid. The process of manufacturing this product is conducted as
follows:-
One part of the alpha naphthol mono sulpho acid is dissolved in three parts
of fuming acid and the melt is slowly heated to the temperature of a water
bath.
At a temperature of 75 degrees Centigrade the whole mass stiffens into a thick
paste of naphthyl sulphuric acid, on further raising the temperature the melt again
becomes thin and at about 90 degrees Centigrade is in the form of a clear liquid.
To isolate the naphthol disulpho acid the melt is converted into the lime salt and
then into soda salt in the usual manner and the soda salt is precipitated in the
form of jelly from the acidulated solutions of the concentrated filtrate, saturated with
common salt. This alpha naphthol disulpho acid couples with difficulty with diazo-
compounds.
A new alpha naphthol trisulpho acid is obtained by treating the naphthasultone or
the naphthol mono or disulpho acid S described in the Specification to the German
Patent No. 40571 or the naphthasultonemono sulpho acid with fuming acid. In
order to obtain the new alpha naphthol trisulpho acid the process is conducted as
follows: according as the naphthasultone or the disulpho acid is employed.
The said acids are allowed to stand with 4 to 5 parts of fuming sulphuric acid
containing 25 per cent. of anhydride at the ordinary temperature until a sample ceases
to form colouring matter with diazo compounds this taking place under the above
mentioned conditions usually after standing about 12 hours.
The sulphonation is completed more quickly at elevated temperatures but not at
temperatures of over 100 degrees Centigrade or with the employment of stronger
fuming acid. The melt is poured on ice and converted into the lime salt and soda
salt in the usual manner.
On concentrating the liquid and acidulating it with hydrochloric acid the soda salt

page_text: of the new naphthol trisulpho acid is completely precipitated from the hot solution in
the form of a heavy sandy powder on the addition of common salt.
As already stated the new acid gives no colouring matters with diazo compounds
which property is highly characteristic. The neutral soda salt dissolves very readily
in water with a green fluorescence. By the action of nitric acid a nitro naphthol
sulpho acid is obtained.
The naphthol sulpho acids herein before described can be converted into new
dihydroxynaphthalene sulpho acids in the usual manner, that is to say by treatment
with caustic alkalies at elevated temperatures in either open or closed vessels.
To obtain the new alpha dihydroxynaphthalene mono sulpho acids from the
herein before descrived new alpha naphthol disulpho acids the latter are melted
with three parts of caustic soda at about 250 degrees Centigrade until a sample
shows a disappearance of the fluorescence and emits a strong odour of sulphurous
acid when acidulated.
The alpha naphthol disulpho acid obtained from the (1: 5) alpha naphthol mono
sulpho acid produces a dihydroxynaphthalene mono sulpho acid the soda salt of which
crystallizes from solutions saturated with common salt in the form of fine shining
plates containing water of crystallization. Chloride of iron produces with this acid
an unstable blue green solution. From one to two drops of solution of chloride of
lime produce a red brown colour which is unchanged by an excess of chloride of lime
solution.
The alpha naphthol disulpho acid, obtained from the (14) alpha naphthol mono
sulpho acid affords a dihydroxynaphthalene mono sulpho acid the soda salt of which
crystallizes from acid solutions saturated with common salt in fine white needles.
With chloride of iron it affords a permanent blue green solution, and with a chloride
of lime solution a blue red solution which an excess renders wine yellow, then
colourless.
When the new naphthol trisulpho acid hereinbefore described is melted with custic
alkali a new dihydroxynaphthalene disulphonic acid is obtained.
The conversion may be conducted in open or closed vessels with or without the aid
of pressure. In the former case concentrated caustic alkali must be employed but
in the latter case the alkali may be diluted. The process may be conducted as follows,
for example:
One part of the above described alpha naphthol trisulpho acid is heated under
pressure to about 250 degrees Centigrade for about 16 hours with two parts of a soda
lye of 35 per cent.
Un using a concentrated soda lye the reaction is almost instantly completel at
200 degrees Centigrade in an open vessel. The completion of the reaction is known
by the disappearance of the fluorescence or by the formation of colouring matter with
diazo compounds. On acidulating the solution of the melt in water after saturation
with common salt the soda salt of the new dihydroxynaphthalene disulpho acid
crystallizes from the hot liquid in white colourless needles.
The naphthol disulpho acid above described prepared by sulphonating the
15 alpha naphthol monosulpho acid as well as the dihydroxynaphthalene mono
and disulpho acids above mentioned are very well adapted for the manufacture of
colouring matters. They combine with diazo and tetrazo compounds forming new
colouring matters, the azo dyestuffs of the new dihydroxynaphthalene sulpho acids
especially being distinguished by the clearness and blueness of their shades.
The above described dihydroxynaphthalene mono sulpho acids produce with the
diazo compounds of aniline, toluidines, xylidines, cumidines, anisidines, alpha and
beta naphthylamine amilo naphthol ethers and their sulpho or carboxy acids very
beautiful red to violet colouring matters.
Bluer shades are obtained with the new dihydroxynaphthalene disulpho acid which
is the most important one because these dyestuffs are of the greatest clearness. Blue
black to green colouring matters are obtained when the diazo compounds of those
amido azo bodies are employed which are produced by the combination of the diazo
compounds of amines, their sulpho or carboxy acids with alpha naphthylamine or

page_text: alpha amido beta naphthol ethers by further diazotizing and then acting on the
above mentioned naphthol disulpho acid (1: 5) and on the dihydroxynaphthalene
mono and disulpho acids described.
Direct dyeing colouring matters are obtained when the aforesaid acids are allowed
to act on the tetrazo compounds of a diamine such as benzidine, orthotolidine,
diamido phenyl tolyl, diamido stilbene, diamido diphenol ethers (dianisidine) mono
alkyl oxybenzidine, diamido mono alkyl oxyphenyl tolyl or their sulpho or carboxy
acids.
In all cases the reaction takes place between molecular proportions. One molecule
of the tetrazo compound is caused to act on 2 molecules of the new acids.
It is well known that in the production of direct dyeing colouring matters, the
combination of the dyestuff components with tetrazo compounds may also be effected
by first causing one molecule of the tetrazo compound to act upon one molecule of
the dyestuff component and then allowing the intermediate product thus formed to
act upon any other dyestuff components for the production of the colouring matter
itself. This property of the tetrazo compounds can be utilized in the present case by
producing in the first place an intermediate product from the alpha naphthol disulpho
acid or the new dihydroxynaphthalone sulpho acids which intermediate product is
caused to act in turn upon any amine or phenol, or the sulpho or carboxy acids
thereof.
In the case of the dihydroxynaphthalene sulpho acids it is preferable to produce
in the first place the intermediate product with another amine or phenol or the sulpho
or carboxy acids thereof and then to allow this to act on the new dihydroxynaphthalene
sulpho acids obtained according to this invention.
Direct dyeing blue azo colouring matters are obtained by the action of para diazo
acet anilide or alpha- diazo- naphthalene- azo- acet anilide upon the sulpho acids
hereinbefore referred to then splitting off the acetyl group and after farther diazotizing
acting on one molecule of a phenol, a naphthol, a dihydroxynaphthalene and the sulpho
or carboxy acids thereof.
Colouring matters dyeing cotton black directly are obtained when the aforesaid
tetrazo compounds or their sulpho or carboxy acids are combined in the first place
with one or with two molecules of alpha naphthylamine or alpha amido beta naphthol
ethers the compound thus obtained being further diazotized and the new tetrazo
compounds allowed to act upon the aforesaid new dyestuff components.
Direct dyeing colouring matters of from blue to blue black shades derived from
para phenylene diamine are produced by diazotizing acetyl para phenylene diamine
coupling it with alpha naphthylamine or alpha amido beta naphthol ether, again
diazotizing and acting on the aforesaid dihydroxynaphthalene sulpho acids, splitting
off the acetyl group and again diazotizing and combining the product with amines,
phenols, and the like in the usual manner.
Useful colouring matters likewise dyeing cotton in an alkaline bath are also
obtained when the diazo compounds of dehydro thio toluidine and dehydro thio
xylidine or their sulpho acids are caused to act upon the new acids. These thio bases
are obtained by heating para toluidine and meta xylidine with sulphur.
The known process is employed for the production of all these azo colouring matters
and consists in allowing the diazo or tetrazo combinations to run into an alkaline or
acetic acid solution of the new acids. In employing the dihydroxynaphthalene disulpho
acid, above described, the method of coupling in an acetic acid solution is preferable.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what
I claim is
I. The production of an alpha naphthol disulpho acid by treating the (1:5) alpha
naphthol monosulpho acid with sulphonating agents.
11. The production of another alpha naphthol disulpho acid by treating the (1 : 4)
alpha naphthol monosulpho acid with sulphonating agents.
III. The production of a new alpha naphthol trisulpho acid by treating the

page_text: aphthasultone or the alpha naphthol monosulpho acid S or the naphthasultone
ono sulpho acid or the alpha naphthol disulpho acid S described in the Specification
f the German Patent No. 40.71 with fuming acid.
IV. The production of new dihydroxynaphthalene mono sulpho acids and of a
ew dihydroxynaphthalene disulpho acid by melting the naphthol disulpho acids of
laims I. and II., and the new naphthol trisulpho acid of Claim III. with caustic
lkalies under pressure or not at a temperature of 200-300 degrees Centigrade.
V. The production of new azo colouring matters by acting with the diazo
ompounds of anilinė, toluidines, xylidines, cumidines, anisidines, phenetidines alpha
aphthylamine, beta naphthylamine, alpha amido alpha naphthol ethers, alpha amido
eta naphthol ethers or their sulpho or carboxy acids upon the alpha naphthol disulpho
cid of Claim I. or upon the new dihydroxynaphthalene sulpho acids of Claim IV.
VI. The production of new diazo colouring matters from the alpba naphthol
isulpho acid of Claim I. and the dihydroxynaphthalene sulpho aciis of Claim IV.
a, by the action of one molecular proportion of the tetrazo compounds of benzidine,
ortho tolidine, diamido phenyltolyl, diamidostilbene, diamidofluorene, diamido-
naphthalene, dianido diphenol ethers, alkyl oxy benzidine, diamidoalkyloxy-
phenyltoly or their sulpho or carboxy acids upon two molecular proportions
of one of the said naphthol or dihydroxy-naphthalene sulpho acids or
b, by the action of the intermediate products formed from one molecular
proportion of one of the tetrazo compounds hereinbefore referred to and
one molecular proportion of a phenol, naphthol, amine, dihydroxynaphthalene
or the sulpho or carboxy acids thereof upon the new naphthol or dihydroxy-
naphthalene sulpho acids of Claims 1. and IV.
VII. The production of intermediate products by the action of one molecular
roportion of one of the tetrazo compounds specified in the 6th claiming clause upon
ne molecular proportion of one of the new dihydroxy naphthalene sulpho acid of
Claim IV. or the alpha naphthol disulpho acid of Claim I.
VIII. The production of blue direct dyeing azo colouring matters by acting with
ara- diazo- acetanilide or alpha- diazo- naphthalene- azo acetanilide- upon phenols,
aphthols, dihydroxynaphthalenes or their sulpho acids splitting off the acetyl
roup, further diazotizing the free amido group and acting with the diazo
ompound upon one molecular proportion of the alpha naphthol disulpho acid or the
ew dihydroxynaphthalene sulpho acids hereinbefore described, whicli combine with
iazo compounds.
IX. The production of azo colouring matters dyeing cotton directly blueish black
y the combination of the tetrazo compounds of the azo bodies (obtained from the
etrazo compounds specified in the 6th claiming clause and one or two molecular
roportions of alpha naphthylamine or alpha amido beta naphthol ethers) with alpha
aphthol disulpho acid or dihydroxynaphthalene sulpho acids substantially as herein-
efore described (Claims I. and IV.).
✗. The production of azo colouring matters (capable of dyeing cotton in an
lkaline bath) by the combination of the diazo compounds of thio toluidine or of thio
ylidin (obtained by heating para toluidine or meta xylidine with sulphur) or their
ulpho acids upon or with alpha naphthol disulpho acid of Claim I. or with dihydroxy-
aphthalene sulpho acids of Claim IV. obtained as hereinbetore described or otherwise.
XI. The production of az colouring matters (capable of dyeing wool black in an
cid bath) by the combination of the diazo compounds of the azo bodies formed from
he diazo compounds of aniline toluidines xylidines alpha naphthylamines beta
aphthylamines their mono or disulpho acids and alpha naphthylamine or alpha
mido beta naphthol ethers upon or with the new alpha naphthol disulpho acid of
Claim I. or of the dihydroxynaphthalene sulpho acid of Claim IV.
XII. The new products and colouring matters of Claims I. to XI.