Manufacture of Blue Dye-stuffs for Cotton.
Year: 1899

page_text: Date of Application, 27th Oct., 1899
Complete Specification Left, 28th June, 1900---Accepted, 28th July, 1900
Manufacture of Blue Dye-stuffs for Cotton.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention (as communicated to me from abroad by The Farbwerke vormals
Meister Lucius and Brüning, of Hoechst a/Main, in the Empire of Germany,
Chemical Manufacturers,) to be as follows:-
My foreign correspondents have found that blue dyestuffs may be obtained by
starting from the condensation products of para-nitrochlorobenzenesulphonic acid or
para-nitrochlorobenzoic acid with amidosalicylic acid.
The condensation may be carried out practically as follows:-
1. 260 parts by weight of para-nitrochlorobenzenesulphonic acid
160 parts of para-amidosalicylic acid and 60 parts of sodium carbonate are heated
with the corresponding quantity of water for 6 hours in a closed vessel to 120° C.
The yellow solution thus produced may be salted out and thus the sodium salt of
the condensation product is obtained in the form of yellow-red needles; if the
solution be acidified with mineral salts, the free sulphonic-carboxylic acid separates
as yellow crystals; they are soluble with comparative difficulty in water, whilst the
red-coloured sodium salt is readily soluble in water. The yellow solution is employed
directly to obtain the amidocompound; for this purpose it is neutralized with
hydrochloric acid and reduced with iron and acetic acid in the usual manner; the
liquid, after reduction, being made alkaline with sodium carbonate and filtered,
is acidified, when the amidosulphoniccarboxylic acid separates as white needles almost
insoluble in water.
000. marts by weight of nara-nitro-ortho-chlorobenzoic acid
160 parts of para-amiḍosalicylic acid and 60 parts of calcium carbonate are heated
with the requisite quantity of water for 6 hours in a closed vessel to 120° C.; on the
solution being concentrated and cooled the greater part crystallizes as red needles
which are readily soluble in water; on acidifying this aqueous solution the free
di-carboxylic acid separates as yellow needles soluble with difficulty in water,

page_text: On reducing as above described there are also obtained white needles of the
amidooxydiphenylaminedicarboxylic acid which are almost insoluble in water.
To produce the blue dyestuffs the nitro- as well as the amido- compounds may
be used.
Into a melted mass of 100 parts by weight of sodium sulphide and 30 parts of
sulphur are introduced at 130° C., 30 parts of para-oxy-para-amidodiphenylamine-
sulphoniccarboxylic acid
OH-
COOH
NH-
SO H
NH₂
and the whole is heated to from 160° to 180° C., till the evolution of hydrogen
sulphide ceases and the mass begins to thicken. It is then dissolved in water,
acidified with sulphuric acid, the leuco-compound being precipitated together with
the sulphur, and then filtered; on treating the precipitate with sodium carbonate
the leuco-compound is re-dissolved: it is then filtered from the sulphur and the
solution is oxidised by introducing a current of air.
The oxidation being complete, the separated dyestuff is filtered off and purified
by dissolving it in water and precipitating with common salt. The dry dyestuff
thus obtained is, when pulverized, a dark powder of copper lustre easily soluble in
water to a beautiful blue, solution; if a mineral acid be added to the aqueous solution
the dyestuff separates as blue flakes. In sulphuric acid the dyestuff is soluble to
greenish-blue solution from which the dyestuff separates as blue flakes on dilution
with water, reducing agents decolorise the aqueous blue solution which again becomes
blue in contact with the air.
EXAMPLE II.
The manufacture of the blue dyestuff from
para o nara-amidadinhanolamine
and the whole is heated to from 160° to 180° C., till the evolution of hydrogen
sulphide ceases and the mass begins to thicken. It is then dissolved in water,
acidified with sulphuric acid, the leuco-compound being precipitated together with
the sulphur, and then filtered; on treating the precipitate with sodium carbonate
the leuco-compound is re-dissolved: it is then filtered from the sulphur and the
solution is oxidised by introducing a current of air.
The oxidation being complete, the separated dyestuff is filtered off and purified
by dissolving it in water and precipitating with common salt. The dry dyestuff
thus obtained is, when pulverized, a dark powder of copper lustre easily soluble in
water to a beautiful blue, solution; if a mineral acid be added to the aqueous solution
the dyestuff separates as blue flakes. In sulphuric acid the dyestuff is soluble to
greenish-blue solution from which the dyestuff separates as blue flakes on dilution
with water, reducing agents decolorise the aqueous blue solution which again becomes
blue in contact with the air.
EXAMPLE II.
The manufacture of the blue dyestuff from para-para-amidodinhanglamine
is carried out in a similar manner.
The dyestuff is also a dark powder of coppery
lustre, soluble in water to a blue solution, its solution in sulphuric acid being a dirty
blue-green. The other properties are quite similar to those of the dyestuff described 3
above; both dyestuffs directly dye cotton blue.
ABEL & IMRAY,
Agents for the Applicant.

page_text: invention (as communicated to me from abroad by The Farbwerke vormals: Meister
Lucius and Brüning, of Hoechst a/Main, in the Empire of Germany, Chemical
Manufacturers,) and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
My foreign correspondents have found that blue dyestuffs may be obtained by
starting from the condensation products of para-nitrochlorobenzenesulphonic acid or
para-nitrochlorobenzoic acid with amidosalicylic acid.
The condensation may be carried out practically as follows:-
1) 260 parts by weight of para-nitrochlorobenzenesulphonic acid
as sodium salt, 160 parts of para-amidosalicylic acid and 120 parts of sodium carbonate
are heated with about four litres of water for 6 hours in a closed vessel to 120° C.
The sodium salt of the condensation product may be salted out from the yellow
solution thus produced and is obtained in the form of yellow-red needles; if the
solution be acidified with mineral acids, the free sulphonic-carboxylic acid separates
as yellow crystals; they are soluble with comparative difficulty in water, whilst the
red-coloured sodium salt readily soluble in water. The yellow solution is employed
directly to obtain the amido-compound; for this purpose it is neutralized with
hydrochloric acid and reduced with iron and acetic acid in the usual manner; the
liquid, after reduction, having been made alkaline with sodium carbonate and filtered,
is acidified, when the amidosulphonic-carboxylic acid separates as white needles almost
insoluble in water.
2) 200 parts by weight of para-nitro-ortho-chlorobenzoic acid
as sodium salt, 160 parts of para-amidosalicylic acid and 120 parts of calcium carbonate
are heated with about 4 litres of water for 6 hours in a closed vessel to 120° C; on
the solution being concentrated and cooled the greater part crystallizes as red needles
which are readily soluble in water; on acidifying this aqueous solution the free
di-carboxylic acid separates as yellow needles soluble with difficulty in water.
On reducing as above described there are also obtained white needles of the amido-
oxydiphenylaminedicarboxylic acid, which are almost insoluble in water.
To produce the blue dyestuffs the nitro- as well as the amido- compounds may be
used

page_text: and the whole is heated to from 160° to 180° C., till the evolution of hydrogen
sulphide ceases and the mass begins to thicken. It is then dissolved in water,
acidified with sulphuric acid, the leuco-compound being precipitated together with
the sulphur, and then filtered; on treating the precipitate with sodium carbonate the
leuco-compound is re-dissolved; it is then filtered from the sulphur and the solution
is oxidised by introducing a current of air.
The oxidation being complete, the separated dyestuff is filtered off and purified by
dissolving it in water and precipitating with common salt. The dry dyestuff thus
obtained is, when pulverised, a dark powder of coppery lustre easily soluble in water
to a beautiful blue solution; if a mineral acid be added to the aqueous solution the
dyestuff separates as blue flakes. In sulphuric acid the dyestuff is soluble to a
greenish-blue solution from which the dyestuff separates as blue flakes on dilution
with water; reducing agents decolorise the aqueous blue solution which again
becomes blue in contact with the air.
is carried out in a similar manner.
The dyestuff is also a dark powder of. coppery lustre, soluble in water to a blue
solution, its solution in sulphuric acid being a dirty blue-green. The other properties
are quite similar to those of the dyestuff described above; both dyestuffs directly dye
cotton blue.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The herein described manufacture of blue dyestuffs for cotton by heating with
sulphur and sulphides of alkali metals at 150 to 200° C. the condensation products
obtained at a temperature above 100° C. from para-amidosalicylic acid with 1:4:5-
nitrochlorobenzene-sulphonic acid and from para-amido-salicylic acid with 1: 4:5
nitrochlorobenzoic acid, or the amido-compounds produced by reducing the said
condensation products.
2. The dyestuffs manufactured as above set forth.