Improvements in the Production or Manufacture of Disazo-dye- stuffs.
Year: 1888

page_text: Date of Application, 23rd Oct., 1888
Complete Specification Left, 23rd July, 1889-Accepted, 24th Aug., 1889
PROVISIONAL SPECIFICATION.
Improvements in the Production or Manufacture of Disazo-dye-
stuffs.
I, JAMES YATE JOHNSON of 47 Lincolns Inn Fields, in the County of Middlesex,
Gentleman, do hereby declare the nature of this invention (which has been communi-
cated to me from abroad by the Badische Anilin and Soda Fabrik of Ludwigshafen
on Rhine in the Empire of Germany) to be as follows:-
This Invention has for its object the production of disazo dye stuffs that is to say
dye stuffs containing twice the azo group-N-N-and the production or manufacture
according to this invention is distinguished from the processes hitherto known or used
in that the combination of two and two molecules of amido-azo-compounds is effected
in the amido groups by means of an intermediary or connecting link. Suitable
intermediaries for such combination of amido-azo compounds are phozgen, thiophozgen,
carbon bisulphide, aldehydes, aethylenbromide or ethers of double basic acids such as
ether of oxalic acid. Practical results have been obtained by combining two and two
molecules of either of the following viz. -para-amido-azo compounds by means of
phozgen, thiophozgen, and carbon bisulphide. The disazo compounds so produced
may also be regarded as azo derivatives of the symmetrical diphenyl urea or thio-urea
and are coloring matters by which cotton can be dyed without a mordant.
The said para-amido-azo compounds are:-
I. Para-ainido-benzol-azo-salicylic acid (Meldola Berichte XVIII R. p. 627).
II. Para-amido-benzol-azo-cresotinic acid (Homo-salicylic acid).
For the production of these amido-azo compounds there may be taken the para-
nitro-diazo-benzol compounds of Meldola or the amido-diazo-benzol of Griess
(Ber. XVII 603) but it is preferred to take the diazo-acetanilid of Nietzki and to
operate according to the following example:
:-
I. PRODUCTION OF A YELLOW DISAZO DYE-STUFF BY MEANS OF PHOZGEN.
15 parts by weight of fine pulverized acetyl-para-phenylen-diamine are dissolved in
a mixture of 45 parts by weight of hydrochloric acid (of 32% H. Cl.) 200 parts by
weight of water and 200 parts by weight of ice. Then seven parts by weight of
nitrite of soda dissolved in three times the quantity of water are added and stirred or
agitated for about an hour. The solution of the diazo compound is allowed to flow
slowly into a solution of 15 parts by weight of salicylic acid, 45 parts by weight of
calcined soda, 300 parts by weight of water and 150 parts by weight of ice. After
standing for about 24 hours the crystalline azo compound precipitates and may be
collected filtered and pressed.
For eliminating its acetyl group the product obtained is without drying introduced
into 300 parts by weight of sulphuric acid of 66° Beaumé and the mixture is heated
in a boiling water bath for about 4 hours and then it is caused to flow slowly into cold
water and the amido-azo compound forms as a fine brown crystalline slime which will
be collected on a filter. For converting this product into a disazo colouring matter it
is well mixed (preferably in a large lead lined vessel) with 750 parts by weight of
water and 450 parts by weight of ice and by carefully adding a solution of soda or of
sodium hydroxide it is converted into its soda salt. Into this mixture whilst it is
agitated phozgen is introduced until an acid re-action is observed. The sulpho acid of
the colouring matter is then separated as a brown slime which is filtered pressed and
well mixed with calcined soda in quantity. sufficient for producing the soda salt.
Finally it is dried on a water bath.

page_text: In this manner the colouring matter is obtained in the form of a brownish yellow
powder which is easily soluble in water and such solutions of it will produce a beautiful
yellow colour on uninordanted cotton.
A dye stuff of a similar character is obtained by the use of cresotinic acid instead of
salicylic acid.
II. PRODUCTION OF A YELLOW DYE STUFF BY MEANS OF THIO-PHOZGEN OR CARBON
BISULPHIDE.
The amido-azo compound obtained in the manner herein before described from
15 parts by weight of salicylic acid is well mixed (preferably in an enamelled vessel)
with 750 parts by weight of water and after neutralizing with soda 18 parts by weight
of thiophozgen will be slowly added to the mixture which is carefully agitated during
the operation. After stirring for about 12 hours the reaction is finished and the
precipitated sulpho-acid of the colouring matter is converted into its soda salt as
herein before described.
Another method of preparing the said colouring matters consists in using carbon
bisulphide instead of thiophozgen. In this case 1 part by weight of the amido-azo
compound 2 parts by weight of carbon bisulphide 5 parts by weight of alcohol and
1 part by weight of hydroxyde of potash are heated in a suitable vessel on a water
bath for say 3 or 4 hours. The alcohol will be distilled off and the residue is
dissolved in water. The sulpho acid of the colouring matter is precipitated by hydro-
chloric acid and the precipitate is converted into its soda salt as hereinbefore
described.
The dyeing properties of the thiourea derivatives are similar to those of the above
described colouring matters not containing sulphur.
Dated : 2
1
COMPLETE SPECIFICATION..
Improvements in the Production or Manufacture of Disazo-dye-
stuffs.
I, JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this Invention (which has been com-
municated to me from abroad by the Badische Anilin and Soda-Fabrik of
Ludwigshafen-on-the-Rhine in the Empire of Germany) and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement :-
This Invention has for its object the production of disazo-dye-stuffs that is to say,
dye stuffs containing twice the azo-group-N-N.
The production or manufacture according to this Invention is distinguished from
the processes hitherto known or used for a similar object in that the said Disazo-dye-
stuffs are obtained by the combination of two and two molecules of amidoazo-
compounds, which combination is effected in the amido-groups by means of an
intermediary or connecting link. Suitable intermediaries or connecting links for
such combination of amido-azo-compounds are phosgen, thiophosgen, carbon bisulphide,
aldehydes, ethylenedibromide or ethers of bibasic acids such as ether of oxalic acid.
Practical results have been obtained by combining two and two molecules of either of
the following Para-amido-azo-compounds by means of phosgen, thiophosgen, and
carbon bisulphide. The disazo-compounds so produced may also be regarded as azo-
derivatives of the symmetrical diphenyl-urea.or diphenyl-thio-urea and are yellow
colouring matters by which cotton can be dyed without the aid of a mordant.
The said para-amido-azo-compounds are:-
1. Para-amido-benzol-azo-salicylic acid. (Meldola, Berichte XVIII R. p. 627).
Para amide hou1

page_text: These amido-azo-compounds may be produced by reducing the corresponding para-
nitro-diazo-benzol combinations (as shewn by Meldola) or the amido-diazo-benzol of
Griess (Berichte XVII 603) may be combined with either salicylic or creosotinic acid,
but it is preferred to take the diazo-acetanilide of Nietzki (Berichte XVII, 343) and
to operate according to the following examples
-
1. PRODUCTION OF A YELLOW DISAZO DYE-STUFF BY MEANS OF PHOSGEN.
Fifteen (15) parts by weight of finely pulverised acetyl-para-phenylene-diamine (para-
amido acetanilide) are dissolved in a mixture of about forty five (45) parts by weight of
hydrochloric acid of 32% HCl), about two hundred (200) parts by weight of water.
and about two hundred (200) parts by weight of ice. Then about seven (7) parts by
weight of nitrite of soda (dissolved in three times the quantity of water) are added
and stirred or agitated for about an hour. The solution of the diazo-acetanilide thus
obtained is allowed to run slowly into a solution of about fifteen (15) parts by weight
of salicylic acid, about forty five (45) parts by weight of calcined soda, about three
hundred (300) parts by weight of water and about one hundred and fifty (150) parts
by weight of ice. After standing for about 24 hours the crystalline. azo-compound
precipitates and is collected upon a filter and well pressed.
For eliminating its acetyl-group the product obtained is without drying introduced
into about two hundred (200) parts by weight of ordinary concentrated or rectified
sulphuric acid and the mixture is heated in a boiling water bath for about four.
hours.
It is then caused to run slowly into cold water, whereby the amido-azo-compound
will be separated as a fine brown crystalline precipitate, which is collected on a
filter.
In order to convert this product into a disazo-colouring matter, according to the
present Invention, it is well mixed (preferably in a large lead lined vessel) with about
one thousand (1000) parts by weight of water and about seven hundred (700) parts
by weight of ice, and then by carefully adding a solution of soda or of sodium
hydroxide it is converted into its sodium salt.
Into this mixture, whilst it is agitated, a current of phosgen-gas is introduced (but
phosgen may also be employed in its liquified condition) until the mixture is observed
to assume an acid reaction. The colouring matter which then separates:out in its free
or uncombined state as a brown precipitate is filtered, pressed and well mixed
with calcined soda in quantity sufficient for producing its sodium salt. Finally this
mixture is dried on a water bath. In this manner the colouring matter is obtained in
the form of a brownish yellow powder, which is easily soluble in water, and such
solutions of it will produce in an alkaline dye-bath a beautiful yellow colour on
unmordanted cotton.
A dye stuff of a similar character is obtained by the use of the equivalent amount
of cresotinic (homosalicylic) acid instead of salicylic acid in the hereinbefore
described process.
2. PRODUCTION OF A YELLOW DISAZO-DYE-STUFF BY MEANS OF THIO-PHOSGEN OR
CARBON BISULPHIDE.
The amido-azo compound obtained in the manner herein before described from
fifteen (15) parts by weight of salicylic acid is well mixed (preferably in an enamelled
vessel) with about seven hundred and fifty (750) parts by weight of water, and, after
neutralizing with soda, about eighteen parts by weight of thiophosgen are slowly
added to the mixture which is carefully agitated during the operation. After stirring
for about twelve hours the reaction is finished and the precipitated colouring matter is
then converted into its sodium salt as herein before described.
Another method of preparing the said colouring matters consists in using carbon
bisulphide instead of thio phosgen.
!

page_text: In this case about one (1) part by weight of the amido-azo-compound about two
(2) parts by weight of carbon bisulphide, about five (5) parts by weight of alcohol
and about one (1) part by weight of caustic potash are heated to ebullition in a
suitable still at reflux on a water bath for; say, three or four hours. The alcohol is
then distilled off and the residue is dissolved in water. From the solution thus
obtained the colouring matter is precipitated in its free or uncombined state by
hydrochloric acid and the precipitate is finally converted into its sodium salt as
herein before described.
A similar yellow Dyestuff is obtained by the treatment of the above named para-
amido-benzol-azo-cresotinic acid either with thiophosgen or with carbon bisulphide in
the hereinbefore described manner.
The dyeing properties of the thiourea derivatives are similar to those of the above
described colouring matters not containing sulphur, but in practice it is preferred to
manufacture the unsulphuretted colouring matter produced by the action of phosgen
upon two molecules of para-amido benzol-azo-salicylic acid as hereinbefore described.
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. As a new manufacture, the production of yellow Disazo dyestuffs (or Azo-
derivatives of the symmetrical Diphenyl-urea) by the action of one molecule of
Phosgen upon two molecules of either Para-amido benzol-azo-salicylic acid or of
Para-amido benzol azo cresotinic acid, substantially as hereinbefore described.
Second. As a new manufacture, the production of yellow Disazo-dyestuffs (or Azo-
derivatives of the symmetrical Diphenyl-thio-urea) by the action of one molecule of
either Thio-phosgen or of Carbon Bisulphide upon two molecules of either Para-amido
benzol-azo-salicylic acid or of Para-amido-benzol-azo-cresotinic acid, substantially as
hereinbefore described.
Dated this 23rd day of July 1889
J. H. JOHNSON & Co.,
Agents.