The Manufacture and Production of New Disazo Dyes.
Year: 1893

page_text: Date of Application, 29th Sept., 1893
Complete Specification Left, 21st June, 1894-Accepted, 21st July, 1894
PROVISIONAL SPECIFICATION.
The Manufacture and Production of New Disazo Dyes.
I, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields, in the County of London,
Patent Agent do hereby declare the nature of this invention (which has been
communicated 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 relates to the manufacture of a new series of disazo dyes by the
combination of diazo-compounds with 14' naphthylene-diamine.
In the Specification of Letters Patent No. 14625 of 1886 granted to John
Henry Johnson on a communication to him from my present foreign correspondents
disazo dyes derived from the said naphthylene diamine are described but those dyes
result from the combination of the tetrazo-compound corresponding to the said
diamine with suitable second components, whereas according to the present
invention the 1-4 naphthylene diamine is itself the second component and one
molecular proportion thereof is caused to combine with two molecular proportions
of the same or of two different diazo compounds. In this way new dyes are
obtained which yield bluish to black shades on animal fibre and which are very fast
against fulling or treatment in the felting machine.
In the preparation the new dyes according to the present invention all the diazo-
compounds derived from primary aromatic amines or their sulpho acids which are
in ordinary use by manufacturers can be employed. The first molecular proportion
of diazo compound is preferably caused to combine with the diamine in the presence
of hydrochloric or acetic acid and the second proportion in alkaline solution.
The following example will serve to further illustrate the nature of the invention
which is however not confined to the said example.
Dissolve about twenty-three parts by weight of 1-4 naphthylene-diamine in
about six hundred parts by weight of water, cool the solution with ice and run in
the diazo-sulphanilic acid obtained in the well-known way from about nineteen and
a half parts of sulphanilate of soda, about fifty parts of hydrochloric acid
(containing about twenty seven per cent. real acid HCI) about four hundred parts of
water and seven parts of sodium nitrite preferably in the form of & ten per cent.
-solution.
The formation of colouring matter begins immediately but is not complete for
some hours, continue stirring say about twelve to twenty four hours in the cold till
a sample on boiling no longer evolves nitrogen. Next treat the mono-azo dye
formed with a solution of about one hundred and twenty parts of calcined soda in
about one thousand parts of water and then run in at a temperature not exceeding
about +5° centigrade the second proportion of diazo-compound, taking say that
obtained in the well known way from about twenty four and a half parts of sodium
naphthionate fifty parts of hydrochloric acid (containing about twenty seven
per cent. real acid HCI) about one thousand parts of water and about seven parts
of sodium nitrite (preferably in 10 per cent. solution). The red solution of mono-
azo-dye turns blue as the disazo-dye forms. Stir for about twenty four hours or
until no evolution of nitrogen is observed on boiling an acidified sample of the
mixture. Precipitate the dye with common salt, filter press and dry. The dye is
obtained in the form of a blue-black powder which is soluble in water yielding
blue solutions.
In the above example as hereinbefore mentioned the equivalent quantity of other
diazo-compounds can be used instead of those therein described thus for instance
instead of the diazo-naphthionic acid, the diazo compound obtainable from about

page_text: nine and three tenths parts aniline can be used. The dye then obtained is some-
what less soluble than that obtained as hereinbefore described and in dyeing yields
rather redder shades.
Dated the 29th day of September 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
The Manufacture and Production of New Disazo Dyes.
I, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of London,
Patent Agent do hereby declare the nature of this invention (which has been
communicated to me from abroad by The Badische Anilin and Soda Fabrik of
Ludwigshafen on 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 relates to the manufacture of a new series of disazo-dyes by the
combination of diazo-compounds with 1'4' naphthylene-diamine.
In the Specification of Letters Patent No. 14625 of 1886 granted to John Henry
Johnson on a communication to him from my present foreign correspondents disazo-
dyes derived from the said naphthylene diamine are described; but those dyes
result from the combination of the tetrazo-compound corresponding to the said
diamine with suitable second components, whereas according to the present
invention the 141 naphthylene-diamine is itself the second component and one
molecular proportion thereof is caused to combine with two molecular proportions
of the same or of two different diazo-compounds. In this way new dyes are
obtained, which yield bluish to black shades on animal fibre, and which are very
fast against fulling, or treatment in the felting machine.
I am aware that descriptions have been published of bodies obtainable from
naphthalene-diamine by combination thereof with diazo-compounds but none of
these products have achieved any technical importance or been of any value
commercially, further these bodies are all described as yielding, on treatment with
nitrous acid, diazo-compounds, these yielding dyes on combination with- suitable
.components and the said bodies were prepared for this purpose (see Letters Patent
No. 174667 and Moniteur Scientique 1889 page 468). The new products
according to this invention are themselves dye-stuffs and do not yield diazo-
compounds on treatment with nitrous acid but are destroyed by that reagent.
In the preparation of the new dyes according to the present invention all the
diazo compounds derived from primary aromatic amines, or their sulpho acids,
which are in ordinary use by manufacturers, can be employed. The first molecular
proportion of diazo compound is caused to combine with the diamine in acid
solution (usually in the presence of hydrochloric or acetic acid) and the. secon !
proportion in alkaline solution.
44.4
31.
The following example will serve to further illustrate the nature of the invention
and the manner in which it can be carried into practical effect but the invention is
not confined to the said example.
The parts are by weight.
t
Dissolve about twenty three parts of 1.41 naphthylene-diamine in, about six
hundred parts of water; cool the solution with ice and run in the diazo-sulphanilic
acid, obtained in the well known way from about nineteen and a half, parts of
sulphanilate of soda, about fifty parts of hydrochloric acid (containing about
twenty seven per cent. real acid HCI) about four hundred parts of water and seven
parts of sodium nitrite preferably in the form of a ten per cent. solution..
The formation of colouring miatter begins immediately but is not complete + for

page_text: some hours, continue stirring say for about twelve to twenty-four hours in the cold
till a sample, on boiling, no longer evolves nitrogen. Next treat the mono-azo-dye
formed with a solution of about one hundred and twenty parts of calcined soda in
about one thousand parts of water and then run in at a temperature not exceeding
about plus five degrees centigrade the second proportion of diazo-compound, taking
say that obtained in the well-known way from about twenty four and a half parts
of sodium naphthionate, fifty parts of hydrochloric acid (containing about twenty-
seven per cent. real acid HCI) about one thousand parts of water, and about seven
parts of sodium nitrite (preferably in ten per cent. solution). The red solution of
mono-azo-dye turns blue as the disazo-dye forms. Stir for about twenty four
hours, or until no evolution of nitrogen is observable on boiling an acidified sample
of the mixture. Precipitate the dye with common salt, filter press and dry. The
dye is obtained in the form of a blue-black powder which is soluble in water
yielding blue solutions therein.
In the above example as hereinbefore mentioned the equivalent quantity of other
diazo-compounds can be used instead of those therein described; thus, for instance,
instead of the diazo-naphthionic acid, the diazo-compound obtainable from about
nine and three tenths parts aniline can be used. The dye then obtained is
somewhat less soluble than that obtained as herein before described and in dyeing
yields rather redder shades.
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 what
I claim is :-
1. The manufacture of new dis-azo-dyes by the combination of one molecular
proportion of 141 naphthylene-diamine with two molecular proportions of diazo-
compound, the combination of the first proportion of diazo-compound being effected
in acid solution and combination of the second proportion of the same or of a
different diazo-compound being effected in alkaline solution, substantially as
described.
2. The manufacture of a new dis-azo dye by the combination of one molecular
proportion of 1.4 naphthylene diamine with one molecular proportion of diazo-
sulphanilic acid in acid solution and one molecular proportion of diazo-naphthionic
acid in alkaline solution substantially as herein described in the example.
3. As new articles of manufacture the new dis-azo dyes derived from
14 naphthylene-diamine such as can be obtained substantially as hereinbefore
described.
Dated this 21st day of June 1894.
JOHNSONS & WILLCOX,
Agents.