Manufacture of Black Colouring Matters Directly Dyeing Cotton.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Manufacture of Black Colouring Matters Directly Dyeing Cotton.
I, CHARLES DENTON ÁBEL,. of Birkbeck Bank Chambers, Southampton Build-
ings, in the County of London, Consulting Engineer and Chartered Patent Agent,
do hereby declare the nature of this invention (as communicated to me from abroad
by Actien-Gesellschaft für Anilin Fabrikation, of Berlin, in the Empire of Ger-
many, Chemical Manufacturers), to be as follows:-
It is well known that by treating para-amidophenol with sulphur and sulphides
of alkalies a colouring matter is produced, the so called Vidal black of commerce
(English Patent No. 23578 of 1893). This dyestuff produces on cotton dark
greenish shades; by subsequent oxidation in the air or by treatment with certain
metallic salts, such as potassium bichromate, ferrous sulphate and the like, the
green shades directly obtained are turned black.
It has further been shown that by heating with sulphur and sulphides of
alkalies certain nitro-oxy-derivatives of diphenylamine there are obtained colouring
matters which directly produce on the fibre black tints without requiring, like
the so-called Vidal-black, a subsequent oxidation. (Compare English Patent
No. 25234 of 1897, French Patent No. 283,559 of 1898.)
My correspondents have found now that the action of sulphur and sulphides
of alkalies on nitro-oxy-derivatives of diphenylamine leads to quite different final
products if the quantities of sulphur and sulphides are varied. If the proportions
indicated in the example of the French Patent 283,559 are used there is obtained
a product dyeing directly black. On the contrary by using smaller proportions
of sulphides of alkalies and especially of sulphur there result products which
which do not dye cotton directly black, but yield like Vidal-black, green tints
which only after subsequent oxidation turn black. The dyestuff thus obtained
is however essentially different from Vidal-black. While the latter dissolves in
water with glass green colour, the aqueous solution of the new product has a fine
blue colour.
If the aqueous solution of Vidal-black is treated by a current of air, no change
is at first noticed but after the oxidation has been carried on for some time the
solution turns more and more blue and at the same time yields only feebly blueish
tints on cotton which are little fast to acids.
On the other hand if a current of air is passed through the aqueous solution
of the new product obtained as above described an altogether different reaction
takes place, a dark coloured precipitate separating after some time from the
liquid.
This precipitate constitutes a dyestuff which directly dyes cotton black shades.
As will be seen from the above the manner of the production of this colouring
matter is essentially different from that described in the English Patent No. 23578
of 1893 or in the French Patent No. 283,559.
The invention is further illustrated by the following example:
10 parts by weight of dinitro-oxy-diphenylaminesulphonic acid, obtained by
the action of dinitrochlorobenzene on para-amidophenol-ortho-sulphonic acid, are

page_text: introduced into a mixture of 25 parts of sodium sulphide and 5 parts of sulphur,
heated to 110° C. The temperature of the mass is gradually raised to 160° C.
and maintained at this point for about 1 hour. The resulting product is dissolved
in about 10 times its weight of water and a current of air is pasted through this
solution until the separation of the black precipitate which is formed is complete.
When this is the case the precipitate is filtered off and dried. The dyestuff thus
obtained dissolves in hot water with violet-black colour; it is more easily soluble
in water containing some sodium sulphide, the solution thus obtained being more
blueish-black than that in hot water. The dyestuff dissolves in concentrated
sulphuric acid with violet colour; it dyes cotton blue-black shades.
Colouring matters of quite similar character are obtained by substituting in
the preceding example for dinitro-oxydiphenylaminesulphonic acid dinitro-
oxydiphenylamine or suitable substitution products thereof, such as for instance
the dinitro-oxydiphenylaminecarboxylic acid resulting from the action of dinitro-
chlorobenzene on para-amidosalicylic acid..
Dated this 19th day of June 1899
ABEL & IMRAY,
Agents for the Applicant.
acture Of DiacA
I, CHARLES DENTON ABEL, of Birkbeck Bank Chambers, Southampton Build-
ings, in the County of London, Consulting Engineer and Chartered Patent Agent,
. do hereby declare the nature of this invention (as communicated to me from abroad
by Actien-Gesellschaft für Anilin Fabrikation, of Berlin, in the Empire of Ger-
many, Chemical Manufacturers) and in what manner the same is to be performed;
to be particularly described and ascertained in and by the following statement-
It is well known that by treating para-amidophenol with sulphur and sulphides
of alkalies a colouring matter is produced, the so called Vidal black of commerce
(English Patent No. 23578 of 1893). This dyestuff produces on cotton dark
greenish shades; by subsequent oxidation in the air or by treatment with certain
metallic salts. such as potassium bichromate, ferrous sulphate and the like, the
green shades directly obtained are turned black.
It has further been shown that by heating with sulphur and sulphides of
alkalies certain nitro-oxy-derivatives of diphenylamine there are obtained colouring
matters which directly produce on the fibre black tints without requiring, like
the so-called Vidal-black, a subsequent, oxidation. (Compare English Patent
No. 25234 of 1897, French Patent No. 283,559 of 1898.)
My correspondents have found now that the action of sulphur and sulphides
of alkalies on nitro-oxy-derivatives of diphenylamine leads to quite different final
products if the quantities of sulphur and sulphides are varied. If the proportions
indicated in the example of the French Patent 283,559 are used there is obtained
a product dyeing directly black. On the contrary by using smaller proportions
of sulphides of alkalies and especially of sulphur there result products which
do not dye cotton directly black, but yield. like Vidal-black, green tints
which only after subsequent oxidation turn black. The dyestuff thus obtained
is however essentially different from Vidal-black. While the latter dissolves in
water with glass green colour, the aqueous solution of the new product has a fine
blue colour.
If the aqueous solution of Vidal-black is treated by a current of air, no change
is at first noticed but after the oxidation has been carried, on for some time the

page_text: solution turns more and more blue and at the same time yields only feebly blueish
tints on cotton which are little fast to acids.
On the other hand if a current of air is passed through the aqueous solution
of the new product obtained as above described an altogether different reaction
takes place, a dark coloured precipitate separating after some time from the
liquid.
This precipitate constitutes a dyestuff which directly dyes cotton black shades.
As will be seen from the above the manner of the production of this colouring
matter is essentially different from that described in the English Patent No. 23578
of 1893 or in the French Patent No. 283,559.
The invention is further illustrated by the following example.
10 parts by weight of dinitro-oxy-diphenylaminesulphonic acid, obtained by
the action of dinitrochlorobenzene on para-amidophenol-ortho-sulphonic acid, are
introduced into a mixture of 25 parts of sodium sulphide and 5 parts of sulphur,
heated to 110° C. The temperature of the mass is gradually raised to 160° C.
and maintained at this point for about 1 hour. The resulting product is dissolved
in about 10 times its weight of water and a current of air is passed through this
solution until the separation of the black precipitate which is formed is complete.
When this is the case the precipitate is filtered off and dried. The dyestuff thus
obtained dissolves in hot water with violet black colour; it is more easily soluble
in water containing some sodium sulphide, the solution thus obtained being more
blueish-black than that in hot water. The dyestuff dissolves in concentrated
sulphuric acid with violet colour; it dyes cotton blue-black shades.
Colouring matters of quite similar character are obtained by substituting in
the preceding example for dinitro-oxydiphenylaminesulphonic acid dinitro-
oxydiphenylamine or suitable substitution products thereof, such as for instance
the dinitro-oxydiphenylaminecarboxylic acid resulting from the action of dinitro-
chlorobenzene on para-amidosalicylic acid.
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:-
1. The herein described manufacture of black colouring matters directly dyeing
cotton, by treating certain nitro-oxy-substituted derivatives of diphenylamine,
such as meta-dinitro-oxydiphenylamine, meta-dinitro-oxydiphenylaminesulphonic
acid or meta-dinitrophenyl-para-amidosalicylic acid (obtained from the action
of meta-dinitrochlorobenzene upon para-amidophenol, para-amidophenolortho-
sulphonic acid or para-amidosalicylic acid respectively) with sulphur and sulphides
of alkali-metals in such proportions as to yield products which do not dye directly
until oxidised, and by then oxidising the products so obtained.
2. The colouring matters manufactured as above set forth.