Improvements in and relating to the Manufacture of Azo Dyestuffs.
Year: 1894

page_text: Date of Application, 9th Jan., 1894
Complete Specification Left, 9th Oct., 1894-Accepted. 10th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Manufacture of Azo Dyestuffs.
I, JAMES YATE JOHNSON, of 47 Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of this invention (which has
been communicated to me from abroad by Kalle & Co., of Biebrich-on-Rhine, in the
Empire of Germany, Manufacturers,) to be as follows:-
Up to the present it is believed that no one has succeeded in preparing the
1.8 amido-naphthol-4.6 disulphonic-acid, which results from the conversion of
the 1.5 naphthalene-disulphonic-acid with fuming sulphuric acid at a low tem-
perature into the 1.3.5 naphthalene trisulphonic acid, transforming the same by
nitrating and reducing into the 1.4.6.8 naphthylamine-trisulphonic-acid and melting
the latter with alkalies. This amido-naphthol-disulphonic acid yields new valuable
dyestuffs when combined with the diazo-derivatives of the monamines, diamines
and their amido-azo-compounds of the general formula:
nhnHg
Ro
n =
nRnH,
R
nH₂
R
R
1= nR'OH,
An=DR"
onR¹DH,
=
D= nR¹¹nH₂
The azo-dyestuffs thus obtained differ according to whether they are produced
in an alkaline or acid solution. Those obtained in an alkaline solution can be
further diazotized either in aqueous solution or on the fibre and conjugated with
amines, phenols and the sulphonic-acids or carboxyl-derivatives thereof, new
valuable coloring matters being thus produced.
By combining however in an acid solution, dyestuffs are obtained, which may be
converted into new dyestuffs, by combining either one equivalent of the same with
one equivalent of a diazo compound, or two equivalents with one equivalent of a
tetrazo-compound.
By using only one equivalent of the dyestuffs in the combination with a tetrazo-
compound, intermediate products result, susceptible of being further combined with
amines, phenols, their sulpho-acids or carboxyl-derivatives.
Also one molecule of the new amidonaphtholdisulphonic-acid can be combined
with one molecule of a tetrazo-compound.
The following is a description of the manner in which this invention can be
carried into practical effect but I do not limit myself to the precise details, the

page_text: I. PREPARATION OF THE AMIDONAPHTHOL-DISULPHONIC-ACID K.
Stir 10 parts of 1.5 naphthalene-disulphonic acid into 10 parts of concentrated
sulphuric acid of 100 per cent. monohydrate, mix at 40 degrees centigrade with
14 parts of fuming sulphuric acid, containing 70 per cent. SO2, and heat the mixture
to from 80° to 90° centigrade, until it becomes liquid and a test portion, diluted
with water, does not precipitate out on the addition of common salt. Run into
the cold mixture 9-2 parts nitrating acid (containing 25 per cent. NHO,) at a
temperature not above 600° centigrade. Allow the mass to stand for a short time
at this temperature and the reaction is finished. Stir the whole into five times its
quantity of water and reduce the nitrosulphonic acid by the addition of filings.
Then treat the mass with lime, convert the calcium salt into the sodium salt and
acidify the filtered solution with hydrochloric acid. On cooling the acid sodium
salt of the naphthylaminetrisulphonic-acid crystallizes out in fine white needles.
This precipitate is melted with 15 parts of caustic soda and 5 parts of water at a
temperature of about from 180 to 200° centigrade. Towards the end of the
reaction the colour of the melt turns from yellow to reddish-brown. Then dissolve
the product in 200 parts of water and precipitate the acid sodium salt of the
amidonaphthol-sulphonic-acid by means of hydrochloric acid.
II. PREPARATION OF PRIMARY AZO-DYESTUFFS.
(A.) The dyestuffs derived from the monamines dye wool from an acid bath
very evenly, the dyes are eminently fast against washing and soaping and also
against the action of light and alkalies. The shades of the dyestuffs vary
(according to the monamine used) from red to bluish violet, the products obtained
in an acid solution having a slightly more yellowish shade.
Example. Pour the diazo-compound from 9.3 parts of aniline into the cold
alkaline solution of 38 parts of amidonaphtholdisulphonic acid K and salt out the
dyestuff when warm. It dyes wool a bluish-red.
The dyestuffs obtained in a similar way by combining the amidonaphthol-
disulphonic-acid K with

page_text: (B.) The dyestuff obtained from p. diamines and the amido naphthol disulphonic
acid K are suitable for dyeing cotton or half wool. The symmetrical-dyestuffs
yield deep pure bluish shades, which are characterized by an excellent fastness
against washing and the action of light and are unaltered by alkalies and acids.
The dyes obtained from the acid solution exhibit a more reddish shade. By
combining one molecule of para-diamine with only one molecule of the amido-
naphthol-disulphonic-acid K intermediate products are obtained, which by com-
bination with phenols, amines, amidophenols and their sulphonic acids or carboxyl-
derivatives yield dyestuffs of red, violet, blue to blue-black shades, according as to
the second component.
Example 1. Pour the diazo compound from 18.4 parts of benzidine into the
cold alkaline solution of 76 parts of amido-naphtholdisulphonic-acid K, heat the
mixture to from 60 to 70° centigrade and precipitate the dyestuff entirely by
means of common salt. The dyestuff dyes unmordanted cotton a bluish green.
The shades of some dyestuffs obtained in a similar manner are shown in the
following table.
Example 2. The diazo solution obtained from 18.4 parts of benzidine is poured
into a cold alkaline solution of 37 parts of amidonaphtholdisulphonic-acid K.
After a few hours the intermediate product is formed; stir it into an alkaline
solution of 28-6 parts of alpha-naphthol mono-sulphonic acid 1.4 and allow it to
stand for about 12 hours; then heat the mass and salt out. The dyestuff thus
resulting dyes unmordanted cotton a bluish violet.

page_text: III. PREPARATION OF SECONDARY AZO-DYESTUFFS.
The combinations of the amidonaphtholdisulphonic acid K with the diazo
derivatives of the amido-azo-compounds derived from the monamines are valuable
in wool dyeing, whilst the combinations with the amido-azo-derivatives of the
diamines are suitable for cotton and half-wool.
(A.) For preparing wool-dyes there are to be used: Amido-azo-benzene, its
homologues and the respective sulphonic acids, the combinations of amido sulphonic
acid with alpha-naphthylamine or the alpha-naphthylamine-mono-sulphonic acid 1.6
or 1.7, and also the combinations of bases with the alpha-naphthylamine-sulphonic-
acids 1.6 or 1.7, before mentioned.
Example 1. Diazotize the amido-azo-compound, resulting from the combination
of 22-3 paits of diazotized naphthionic-acid and 143 parts of alpha-naphthylamine,
pour it in the alkaline solution of 34 parts of amido-naphtholdisulphonic K, and
salt out, after the dyestuff is formed. It dyes wool greenish-black shades.
Example 2. Diazotize 22-3 parts of naphthionic-acid in the usual manner,
combine it with 22.3 parts of naphthylamine sulphonic acid 1.7, diazotize the
amidoazo compound, thus obtained after a few hours with 7.1 parts of nitrite of
sodium, and then pour the whole into the alkaline solution of 39 parts of amido-
naphthol disulphonic-acid K. After 24 hours the dyestuff is formed; heat to
about 40° to 60° centigrade and salt out. The dyestuff dyes wool black-shades
which are bluer than the shades obtained with naphthol-black 6 B.
(B.) Cotton dyes. According to the succession of the combinations and the
choice of the components four different groups are to be distinguished.
(1.) One molecule of the usual para-diamines is combined with two molecules of
alpha-naphthylamine or alpha-naphthylamine sulphonic acid 1.6 or 1.7 and the
body thus obtained is converted into the tetrazo-compound and the latter is
conjugated with two molecules of the amido-naphtholdisulphonic acid K.
Example. Convert 9.2 parts of benzidine in the usual mauner into the tetrazo
compound combine this in a slightly acid solution with 14.3 parts of alpha-naphthyl-
amine, allow to stand for some time, add 15 parts of hydrochloric acid and diazotize
with an aqueous solution of 7.2 parts of nitrite of sodium, then pour the liquid into
an alkaline solution of 37 parts of amidonaphthol-disulphonic-acid K. After 36 hours
the dyestuff is formed. It dyes cotton greenish black.
(2.) One molecule of the usual para-diamines is combined with one molecule
alpha-naphthylamine or alpha-naphthylamine-sulphonic acid 1.6 or 1.7 respectively,
the intermediate product thus obtained is furthei diazotized and conjugated with
two molecules of the amido naphthol disulphonic-acid K.
Example. Diazotize the intermediate product, resulting from 9.2 parts of
benzidine and 7-15 parts of alpha-naphthylamine, with 15 parts of hydrochloric acid
and 3-6 parts of nitrite of sodium. Then pour the liquid into an alkaline solution
of 34 parts of amido-naphthol-disulphonic-acid K. After 36 hours the dyestuff is
formed. It dyes cotton indigo blue.
(3.) The dyestuffs obtained by combining one molecule of the usual para-diamines
with one molecule of an amine or phenol or their sulphonic acids or carboxyl-
derivatives and one molecule alpha-naphthylamine or alpha-naphthylamine-sulphonic-
acid 1.6 or 1.7 respectively, are diazotized with one molecule nitrite of sodium and
united with one molecule of the amido-naphthol-disulphonic acid K.
Example. 567 parts of the composed dyestuff resulting by the combination of
1 molecule of tolidine with one molecule of salicylic acid and one molecule of
alpha-naphthylamine-sulphonic acid 1.7 are diazotized in an acid solution with
071 parts of nitrite of sodium and conjugated with the alkaline solution of 3.4 parts
of amidonaphthol disulphonic K. After standing about 24 hours the dyestuff is
salted out. It dyes cotton a moss-green.
(4. The dyestuff' obtained by combining one molecule of p-diamine with one
molecule of alpha-naphthylamine or alpha-naphthylamine sulphonic acid 1.6 or 1.7

page_text: respectively and one molecule of an amidonaphtholsulphonic-acid are transformed
into the corresponding tetrazo compound and the latter conjugated with two
molecules amidonaphtholdisulphonic acid K.
Example. Diazotize 5.74 parts of the composed dyestuff from benzidine and one
molecule amidonaphtholsulphonic-acid G with 1-42 parts of nitrite of sodium in
acid solution and pour the result into an alkaline solution of 7.4 parts of amido
naphthol-disulphonic acid K. Allow to stand for about 24 to 36 hours and salt out.
The dyestuff thus obtained dyes cotton a greenish blue.
IV. COMBINATIONS OF THE DYESTUFFS DESCRIBED UNDER II & III
WITH AMINES AND PHENOLS.
The dyestuffs described under II & III and produced in the presence of an
alkali can be diazotized directly on the fibre or in an acid solution and combined
with amines, phenols, amidophenols and their sulpho acids or carboxyl derivatives.
Example 1. The dyestuff, resulting from the combination of 18-2 parts of
benzidine with 34 parts of amido-naphtholdisulphonic acid K in an alkaline solution,
is diazotized with 14.2 parts of nitrite of sodium; the mixture is then poured into
the alkaline solution of 70 parts of amido naphtholdisulpho acid K. After about
36 hours the dyestuff is salted out. It dyes cotton dark indigo blue.
Example 2. The intermediate product obtained by combining 18.2 parts of
benzidine and 13.8 parts of salicylic acid is introduced into an alkaline solution
of 34 parts of amidonaphtholdisulphonic acid K. After 24 hours acidify, and
diazotize with 7.1 parts of uitrite of sodium and pour the diazo compound formed
into a solution of 21 parts of sulphate of phenylenediamine. After standing some
time alkalize the mixture and heat slowly to about 40 to 60° centigrade and salt
The dyestuff obtained dyes wool brown.
out.
V. COMBINATION OF ONE EQUIVALENT OF THE AMIDONAPHTHOL
DISULPHO ACID K WITH 2 DIAZO-GROUPS.
one molecule is conjugated either with a further molecule of a diazo compound,
yielding a dyestuff, or with one molecule of a tetrazo compound, yielding an
intermediate product, which by further combination with amines phenols and their
sulpho-acids or carboxylic derivatives can be converted into dyestuffs.
(b) Two molecules of the amido-azo-compounds mentioned under (a) are combined
with one molecule of a tetrazo compound.
(c) Of the dye-stuffs obtained by combination of a tetrazo compound of the

page_text: combined with one or two molecules of a diazo-compound or with one molecule of a
tetrazo-compound.
Example 1. Into a well cooled solution of 34 parts of amido-naphtholdisulphonic-
acid K in 600 parts of water and 36 parts of soda the diazo compound of 18 6 parts
of aniline is gradually added under constant stirring. After 36 hours the temperature
is raised to 50° centigrade and maintained for some hours; the dyestuff is then
salted out filtered off and pressed. It dyes wool black.
Example 2. Pour the diazotized solution of 13.8 parts of nitraniline into the
neutral solution of 34 parts of amidonaphtholdisulphonic acid K and 800 parts of
water. After about two hours render the whole strongly alkaline and add the
diazo solution of 13 8 parts of nitraniline. The dyestuff precipitates. It dyes wool
black in an acid bath and it dyes cotton greenish black in a salt bath.
The shade of other dyestuffs obtained in an analogous manner are indicated in
the following table.
By using the sulpho-acids of aniline, amido-azo-benzole or alpha-naphthylamine,
similar dyestuffs, more readily soluble are obtained.
Example 3. Diazotize 13.8 parts of para-nitraniline and combine it in an acid
solution with 34 parts of amidonaphtholdisulpho acid K treat with an excess of
soda and add the tetrazo solution of 9.1 parts of benzidine. Precipitate the
yestuff from the hot solution by means of common salt. It dyes wool in alkaline
bath green.

page_text: Instead of benzidine, tolidine or dianisidine may be employed.
Example. The aqueous solution of the dyestuff resulting from the combination
of 13-8 parts of para-nitraniline with 34 parts of amidonaphtholdisulphonic acid K
is rendered alkaline and mixed with the tetrazo-compound of 9.1 parts of benzidine.
After some time the intermediate product is formed. Then add an aqueous solution
of 14 parts of salicylic acid in 6 parts of soda, allow to stand for a short time and
salt out. The dyestuff obtained, dyes cotton bluish green.
Other dyestuffs are produced in a similar manner by replacing the salicylic acid
Improvements in and relating to the Manufacture of Azo Dyestuffs.
1, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of London,
Gentleman, do hereby declare the nature of this invention (which has been com-
municated to me from abroad by Kalle & Co. of Biebrich on Rhine in the
Empire of Germany, Manufacturers) and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement :-
Up to the present it is believed that no one has succeeded in preparing
the 1.8 amido naphthol 4.6 disulpho acid, which results from the conversion of
the 1.5 naphthalene-disulpho-acid with fuming sulphuric acid at a low temperature
into the 1.3.5 naphthalene trisulpho-acid, transforming the same by nitrating and
reducing into the 1.4.6.8 naphthylamine-trisulpho-acid and melting the latter with
alkalies. This 1.8 amido-naphthol 4.6 disulpho-acid which may be termed amido-
naphthol disulpho acid K yields new valuable dyestuffs when combined with the

page_text: diazo derivatives of the monamines, diamines and their amido-azo compounds of
the general formula
RN=
NHANH,
✓ N
=
NRANH,
R
NH,
N = NBINH,
R
N = NR"
N = NRANH,
R
N = NRANH,
The azo dyestuffs thus obtained differ according to whether they are produced
in an alkaline or in an acid solution. Those obtained in an alkaline solution can
be further diazotised either in aqueous solution or on the fibre and combined with
amines, phenols and the sulpho-acids or carboxyl-derivatives thereof, new valuable
colouring matters being thus produced.
By combining however in an acid solution dyestuffs are obtained which may be
converted into new dyestuffs, by combining either one equivalent of the first
mentioned dyestuffs with one equivalent of a diazo compound or two equivalents of
the first mentioned dyestuffs with one equivalent of a tetrazo compound.
By using only one equivalent of the dyestuff in combination with a tetrazo-
compound, intermediate products result, susceptible of being further combined with
amines, phenols, their sulpho-acids or carboxyl derivatives.
Also one molecule of the new amido naphthol-disulpho acid can be combined with
one molecule of a tetrazo compound.
The following
a description of the manner in which this invention can be
carried into practical effect but I do not limit myself to the precise details.
The parts are by weight and by "molecule" and "molecules "I mean molecular
proportions.
I.
PREPARATION OF THE AMIDONAPHTHOL-DISULPHO ACID K.
Stir 10 parts of 15 naphthalene-disulpho acid into 40 parts of concentrated
sulphuric acid of 100 per cent. monohydrate, mix at 40 degrees centigrade with
9 parts of fuming sulphuric acid, containing 70 per cent. SO,, and heat the mixture
to from 80° to 90° centigrade until it becomes liquid and a test portion, diluted
with water, does not precipitate out on the addition of common salt. Run into the
cold mixture 9.2 parts, nitrating acid (containing 25 per cent. NHO,) at a tem-
perature not above 60° centigrade. Allow the mass to stand for a short time at
this temperature and the reaction is finished. Stir the whole into five times its
quantity of water and reduce the nitro sulpho acid by the addition of filings. Then
treat the mass with lime, convert the calcium salt into the sodium salt and acidify the
filtered solution with hydrochloric acid. On cooling the acid sodium salt of the naph-
thylaminetrisulpho acid crystallizes out in fine white needles. This precipitate is
melted with 15 parts of caustic soda and 5 parts of water at a temperature of
about from 140° to 200° centigrade. Towards the end of the reaction the colour of
the melt turns from yellow to reddish-brown. Then dissolve the product in
200 parts of water and precipitate the acid sodium salt of the amidonaphthol-sulpho
acid by means of hydrochloric acid. The same melt can also be performed in
closed vessels.

page_text: II. PREPARATION OF PRIMARY AZO-DYESTUFFS.
(A.) The dyestuffs derived from the monamines dye wool from an acid bath very
evenly, the dyes are eminently fast against washing and soaping and also against
the action of light and alkalies. The shades of the dyestuffs vary (according to
the monamine used) from red to bluish-violet, the products obtained in an acid
solution having a slightly more yellowish shade.
Example. Pour the diazo-compound from 9.3 parts of aniline into the cold
alkaline solution of 38 parts of amido naphtholdisulpho acid K and salt out the
dyestuff when warm. It dyes wool a bluish-red.
The dyestuffs obtained in a similar way by combining the amido-naphthol-disulpho
acid K with
(B.) The dyestuff obtained from p-diamines and the amidonaphtholdisulpho
acid K are suitable for dyeing cotton or half wool. The symmetrical dyestuffs
yield deep pure bluish shades, which are characterized by an excellent fastness
against washing and the action of light and are unaltered by alkalies and acids.
The dyes obtained from the acid solution exhibit a more reddish shade. By
combining one molecule of para-diamine with only one molecule of the amido
naphthol disulpho acid K intermediate products are obtained, which, by combination
with phenols, amines, amidophenols and their sulphonic acids or carboxyl derivatives,
yield dyestuff's of red, violet, blue to blue black shades, according as to the second
component.
Example 1. Pour the diazo-compound from 18.4 parts of benzidine into the cold
alkaline solution of 76 parts of amido-naphtholdisulpho-acid K, and after some
hours heat the mixture to from 60° to 70° centigrade and precipitate the dyestuff
entirely by means of common salt. The dyestuff dyes unmordanted cotton a
bluish green.

page_text: Example 2. The diazo solution obtained from 18.4 parts of benzidine is poured
into a cold alkaline solution of 37 parts of amido-naphtholdisulpho-acid K. After
a few hours the intermediate product is formed, stir it into an alkaline solution
of 28-6 parts of alpha-naphthol monosulpho-acid 1.4 and allow it to stand for about
12 hours, then heat the mass and salt out. The dyestuff thus resulting dyes
unmordanted cotton a bluish-violet.

page_text: III.
PREPARATION OF SECONDARY AZO-DYESTUFFS.
The combinations of the amidonaphtholdisulpho acid K with the diazo derivatives
of the amido-azo-compounds derived from the monamines are valuable in wool
dyeing, whilst the combinations with the amido-azo-derivatives of the diamines are
suitable for cotton and half wool.
(A.) For preparing wool dyes there are to be used :-Amido azo benzene, its
homologues and the respective sulpho acids the combinations of diazo sulpho acid
with alpha naphthylamine or the alpha naphthylamine mono-sulpho acil 1.6 or 1.7
and also the combinations of diazo derivatives of mon-amines with the alphanaphthyl-
amine sulpho acids 1.6 or 1.7 before mentioned.
Example 1. Diazotise the amido-azo-compound resulting from the combination
of 22-3 parts of diazotized naphthionic acid and 14.3 parts of alpha naphthylamine,
pour it into the alkaline solution of 34 parts of amido-naphtholdisulpho K, and salt
out, after the dyestuff is formed. It dyes wool greenish black shades.
Example 2. Diazotise 22.3 parts of naphthionic acid in the usual manner,
combine it with 22.3 parts of naphthylamine sulpho acid 1.7 diazotize the amido
azo compound, thus obtained, after a few hours with 71 parts of nitrite of sodium,
and then pour the whole into the alkaline solution of 39 parts of amidonaphthol-
disulpho acid K. After 24 hours the dyestuff is formed. Heat to about 40° to
60° centigrade and salt out. The dyestuff dyes wool black shades which are
biuer than the shades obtained with naphthol-black 6 B.
(B.) Cotton dyes. According to the succession of the combinations and the
choice of the components four different groups are to be distinguished.
(1.) One molecule of the usual para-diamines is combined with two molecules of
alpha-naphthylamine or alpha-naphthylamine sulpho acid 1.6 or 1.7 and the body
thus obtained is converted into the tetrazo-compound and the latter is combined
with two molecules of the amido-naphtholdisulpho acid K.
Example. Convert 9.2 parts of benzidine in the usual manner into the tetrazo-
coinpound combine this in a slightly acid solution with 143 parts of alpha-
naphthylamine, allow to stand for some time, add 15 parts of hydrochloric acid and
diizotise with an aqueous solution of 7-2 parts of nitrite of sodium, then pour the
liquid into an alkaline solution of 37 parts of amido-naphtholdisulpho acid K.
Aiter 36 hours the dyestuff is formed. It dyes cotton greenish-black.
(2.) One molecule of the usual para-diamines is combined with one molecule of
alpha-naphthylamine or alpha-naphthylamine sulphonic acid 1.6 or 1.7 respectively
the intermediate product thus obtained is further diazotised and combined with
two molecules of the amido naphthol disulphonic acid K.
Example. Diazotise the intermediate product resulting from 9.2 parts of
benzidine and 7-15 parts of alpha naphthylamine with 15 parts of hydrochloric acid
and 3-6 parts of nitrite of sodium. Then pour the liquid into an alkaline solution
of 34 parts of amido-naphthol disulpho acid K. After 36 hours the dyestuff is
formed. It dyes cotton indigo blue.
(3.) The dyestuffs obtained by combining one molecule of the usual para-diamines
with one molecule of a phenol or their sulpho acids or carboxyl-derivatives and one
molecule of alpha-naphthylamine or alpha-naphthylamine sulphonic acid 1.6 or 1.7
respectively are diazotised with one molecule of nitrite of sodium and united with
one molecule of the amido-naphthol disulpho acid K.
Example. 567 parts of the composed dyestuff resulting by the combination of
one molecule of tolidine with one molecule of salicylic-acid and one molecule of
alpha-naphthylamine-sulpho acid 1.7 are diazotised in an acid solution with
0.71 parts of nitrite of sodium and combined with the alkaline solution of 34 parts of
amidonaphtholdisulpho K. After standing about 24 hours the dyestuff is salted
It dyes cotton a moss-green.
out.
(4.) The dyestuff obtained by combining one molecule of p-diamine with one
molecule of alpha-naphthylamine or alpha-naphthylamine sulpho acid 1.6 or 1.7

page_text: respectively and oue molecule of an amido-naphthol sulpho acid are transformed
into the corresponding tetrazo compound and the latter combined with two molecules
of amido naphtholdisulpho acid K.
Example. Diazotise 5.74 parts of the composed dyestuff from benzidine and one
molecule amidonaphtholsulpho acid G with 1-42 parts of nitrite of sodium in acid
solution and pour the result into an alkaline solution of 7.4 parts of amido naphthol-
disulpho acid K. Allow to stand for about 24 to 36 hours and salt out.
dyestuff thus obtained dyes cotton a greenish-blue.
The
IV. COMBINATIONS OF THE DYESTUFFS DESCRIBED UNDER II AND III
WITH AMINES AND PHENOLS.
The dyestuffs described under II and III and produced in the presence of an
alkalı can be diazotised directly on the fibre or in an acid solution and combined
with amines, phenols, amido-phenols and their sulpho acids or carboxyl
derivatives.
Example 1. The dyestuff resulting from the combination of 18.2 parts of
benzidine with 34 parts of amido-naphtholdisulpho acid K in an alkaline solution
is diazotised with 14.2 parts of nitrite of sodium, the mixture is then poured into
the alkaline solution of 70 parts of amido-naphthol disulpho acid K. After about
36 hours the dyestuff is salted out. It dyes cotton dark indigo blue.
Example 2. The intermediate product obtained by combining 18.2 parts of
benzidine and 13-8 parts of salicylic acid is introduced into an alkaline solution
of 34 parts of amidonaphtholdisulpho acid K. After 24 hours acidify and diazotize
with 71 parts of nitrite of sodium and pour the diazo-compound formed into a
solution of 21 parts of sulphate of phenylene diamine. After standing some time,
alkalize the mixture and heat slowly to about 40 to 60° centigrade and salt out.
The dyestuff obtained dyes wool brown.
V. COMBINATION OF ONE EQUIVALENT OF THE AMIDONAPHTHOL DISULPHO
ACID K WITH Two DIAZO GROUps.
Three classes of dyestuffs are here to be distinguished.
(u) Of the azo dyestuff's obtained by combining equivalent quantities of the
thallin
One molecule is combined either with a further molecule of a diazo compound
yielding a dyestuff, or with one molecule of a tetrazo-compound, yielding an inter- 35
mediate product, which by further combination with amines phenols and their
sulpho acids or carboxylic-derivatives can be converted into dyestuffs.
(b) Two molecules of the amido-azo-compounds mentioned under (a) are
combined with one molecule of a tetrazo-compound.
(c) Of the dye-stuff's obtained by combination of a tetrazo compound of the 40
general formula

page_text: with two equivalents of the amido naphthol disulpho acid K one molecule is
combined with one or two molecules of a diazo compound or with one molecule of
a tetrazo compound.
Example 1. Into a well cooled solution of 34 parts of amido-naphtholdisulpho
acid K in 600 parts of water and 36 parts of soda, the diazo compound of 18.6 parts
of aniline is gradually added under constant stirring. After 36 hours the tempera-
ture is raised to 50° centigrade and maintained for some hours, the dyestuff is then
salted out, filtered off and pressed. It dyes wool black.
Example 2. Pour the diazotized solution of 13-8 parts of nitrauiline into the
neutral solution of 34 parts of amido-naphthol di-sulpho acid K and 800 parts of
water. After about two hours render the whole strongly alkaline and add the
diazo solution of 13.8 parts of nitraniline. The dyestuff precipitates. It dyes
wool black in an acid bath and it dyes cotton greenish-black in a salt bath.
The shade of other dyestuffs obtained in an analogous manner are indicated in
the following table.

page_text: Example 4. The aqueous solution of the dyestuff resulting from the combination
of 13-8 parts of para-nitraniline with 34 parts of amido naphthol disulpho acid K is
rendered alkaline and mixed with the tetrazo compound of 18.4 parts of benzidine.
After some time the intermediate product is formed. Then add an aqueous solution
of 14 parts of salicylic acid in 6 parts of soda allow to stand for a short tune and
salt out.
The dyestuff obtained, dyes cotton bluish-green.
Other dyestuffs are produced in a similar manner by replacing the salicylic acid
by the compounds named in the first column of the following table viz. :-
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed I declare that I am aware of the
Specifications of Letters Patent No. 17141° A.D., 1893, and No. 20579 A.D., 1893,
granted to Henry Edward Newton and I wish it to be understood that I do not
claim anything described and claimed therein, moreover I do not confine myself to
the exact details of the processes herein before given, but what I claim is
1. The production of 1.8 amido-naphthol 4.6 disulpho-acid by converting
1.5 naphthalene disulpho acid with fuming sulphuric acid into 1.3.5 naphthalene-
tri-sulpho-acid transforming the same by nitrating and reducing into 1.4.6.8
naphthylamine tri-sulpho-acid and melting the latter with alkalies.
2. The production of azo dyes by combining the said 1.8 amido-naphthol 4.6
disulpho acid with diazo or tetrazo compounds, substantially as hereinbefore
described.
Dated this 9th day of October 1894.
JOHNSONS & WILLCOX.