Improvements in the Manufacture and Production of Azo Dyes.
Year: 1890

page_text: Date of Application, 22nd Aug., 1890
Complete Specification Left. 22nd May, 1891-Accepted, 27th June, 1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture and Production of Azo Dyes.
I, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of Middlesex,
Patent Agent, do hereby declare the nature of this invention (which has been
communicated to me from abroad by the Farbenfabriken vormals Friedrich Bayer
& Co. of Elberfeld in the Empire of Germany) to be as follows:-
By the action of a tetrazo compound upon salicylic acid or cresol carbon acid
and alpha naphthylamine or alpha amido naphthol ether in equal molecular
proportions or first upon alpha naphthylamine or alpha amido naphthol ether and
then upon salicylic acid or cresol carbon acid all in equal molecular proportions
colouring matters are obtained known as mixed salicylic or cresol carbon acid
colouring matters.
By subjecting such colouring matter to the action of nitrous acid the
amido group of the alpha naphthylamine contained in this colouring matter
becomes diazotised.
New diazo compounds are thus obtained which by acting on suitable dyestuff
components lead to the production of a new and extremely valuable class of
colouring matters.
With the employment of amines for instance fast brown to brown black
substantive azo colouring matters are obtained, whilst with the employment of
naphthols and their sulpho acids olive-coloured Russian green to deep black products
are obtained.
As salicylic acid colouring matters the new products partake of the properties of
the known colouring matters derived from these acids, they are unaffected by light
and possess great colouring power.
The manufacture of this new class of colouring matter constituting this invention
is conducted in general as next hereinafter described.
diamido-phenol-ether,
The tetrazo compounds comprising those derived from the known para-diamines
namely benzidine, tolidine, diamido-phenyl-tolyl, diamido-mono-ethoxy-diphenyl,
diamido-azo-benzol,
diamido-mono-ethoxy-phenyl-tolyl,
diamido-azoxybenzol, diamido-stilbene, diamido-fluorene, diamido-naphthalene,
diamido-carcasol, diamido-phenylene-oxide, diamido-toluylene-oxide, paraphenylene-
diamine, amido-naphthalene-azo-aniline benzidine or tolidine and diamido-phenyl-
tolyl-sulphone as well as the mono- and di-sulpho acids and carboxy acids of the
above mentioned bases are allowed to act in the known manner upon one molecule
of salicylic or cresol carboxy acid and the intermediate product formed is coupled
in an acetic acid solution with one molecular proportion of alpha-naphthylamine or
alpha-amido-naphthol-ether. Heat is applied in order to remove any alpha-
naphthylamine or amido-naphthol-ether that may have failed to enter into reaction
and the product is filtered off after acidulation with hydrochloric acid.
The mixed colouring matters thus obtained being made into slime or paste with
alkali are mixed with the calculated quantity of nitrate and diazotised by
acidulation with hydrochloric acid whilst stirring. The diazotising is concluded
after standing for say 12 hours; the insoluble diazo compound obtained is filtered
off and introduced into the alkaline solution of a phenol or into the acetic acid
solution of an amine. To complete the formation of the colouring matter heat is
directly applied by means of a water bath and when the coupling is performed in an
acetic acid solution the materials are rendered alkaline with soda lye. The
colouring matters are isolated by salting out and filtration.
The following are given as some examples of the manufacture of the new colouring
matters in practice the parts being by weight.

page_text: Benzidine +1 molecular proportion of salicylic acid + 1 molecular proportion of
pha-naphthylamine + 1 molecular proportion of alpha-naphthol-alpha-mono-
ulpho-acid.
5 parts of nitrite corresponding to the colouring matter (Benzidine + 1 molecular
proportion of salicylic acid + 1 molecular proportion of alpha naphthylamine) are
made into slime or paste with water, mixed with alkali and a solution of 3 parts of
nitrite cooled to 0 degrees Centigrade and acidulated by stirring with hydrochloric
acid.
As the diazotising progresses the precipitate, which is of a brown-black colour at
first, acquires a clearer colour and after standing for say 12 hours becomes brown-
red. It is then filtered off and the diazo compound obtained is introduced into a
solution of 10 parts of alpha-naphthol-mono-sulpho-acid maintained alkaline. After
heating to 80 degrees Centigrade the colouring matter separated is filtered off and
dried. This product dyes in an alkaline bath unmordanted cotton a deep black.
Diamido-stilbene-disulpho-acid + 1 molecular proportion of salicylic acid +
1 molecular proportion of alpha-naphthylamine + 1 molecular proportion of meta-
phenylene-diamine.
The mixed colouring matter corresponding to 5 parts of nitrite diamido-stilbene-
disulpho-acid +1 molecular proportion of salicylic acid + 1 molecular proportion
of alpha-naphthylamine, are dissolved in alkali mixed with 3 parts of nitrite cooled
to 0 degrees Centigrade and for further diazotising are acidulated with hydrochloric
acid. After standing for say 12 hours the diazo compound obtained is filtered off
and placed in an acetic acid solution of 5 parts of meta-phenylene-diamine. It is
then heated to 80 degrees Centigrade, made alkaline with soda lye and the
colouring matter formed is salted out and separated by filtration. It dyes a 4
brownish-black.
The shades of the colouring matters obtained by means of this process are little
influenced by the tetrazo compounds of the above mentioned para-diamines but
depend chiefly on the nature of the dyestuff components employed.

page_text: The following colours may be obtained for example :-
With alpha-naphthylamine-sulpho-acid and resorcin--brown.
With alpha-naphthol-mono-sulpho-acid (Piria and Cleve)—black.
With alpha-naphthol-disulpho-acid-S (German Patent 40571)-olive.
With alpha-naphthol-disulpho-acid (German Patent 45776)-grey-black.
With beta-naphthol-mono-sulpho-acid (Schäffer)-violet-black.
With beta-naphthol-disulpho-acid-G, R or F-green-black.
With dioxy-naphthalene-mono-sulpho-acid-G or S-olive to Russian-green.
With naphthol carboxy acid-violet-black.
With dioxynaphthalene 1-8-green-black.
According to the process constituting this invention those colouring matters
which are derived from the sulpho-acids of the above mentioned para-diamines
yield with meta-phenylene-diamine and its sulpho-acids and likewise with alpha-
naphthylamine, alpha- and beta-naphthol colouring matters from violet to brown-
black.
Dated this 22nd day of August 1900
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture and Production of Azo Dyes.
I BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of Middlesex
Patent Agent do hereby declare the nature of this invention which invention
has been communicated to me from abroad by Farbenfabriken vormals Friedrich
Bayer & Co. of Elberfeld 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 :-
By combining one molecular proportion of any tetrazo compound with one
molecular proportion of salicylic acid or cresol carboxylic acid and one molecular
proportion of alpha naphthylamine or alpha amidonaphthol ether so called mixed
salicylic or cresol carboxylic acid colouring matters are obtained.
The amido group of the alpha-naphthylamine contained in these colouring
matters is easily diazotised and the resulting new diazo compounds may be
combined with several dyestuff components to form new and valuable colouring
matters.
By means of amines, for instance, fast brown or brown-black substantive azo
colouring matters may be produced whilst naphthols or dihydroxy-naphthalenes
and their sulpho-acids afford olive-coloured, Russian green or deep black products.
The practical manufacture of these new colouring matters is performed in general
as hereinafter described.
The tetrazo compounds derived from the known para-diamines-benzidine, ortho-
tolidine, diamido-phenylorthotolyl, diamidomono-alkyloxy-, diphenyl, diamido-
monoalkyl-oxyphenyltolyl, diamido orthodiphenol ether, diamido-azoxybenzene,
diamido stilbene, diamido fluorene, diamido carbazol, diamido diphenylenylene-
oxide, diamido ditoluylene oxide, the sulphones of benzidine or orthotolidine and
diamidophenyltolyl as well as the mono- and di-sulpho acids and carboxylic acids
of the above mentioned bases, are combined in molecular proportions with salicylic
or cresol carboxylic acid. The intermediate product thus formed is combined in
an acetic acid solution with one molecular proportion of alpha-naphthylamine or
alpha-amido-naphthol ether, care being taken that the whole quantity of alpha-
naphthylamine or amidonaphthol ether, is caused by heating to take part in the
reaction. After acidulation with hydrochloric acid the separated product is
filtered off.
These colouring matters after having been mixed with alkalies so as to form a

page_text: sludge or paste are diazotised, by adding the calculated quantity of sodium nitrite
and acidulating with hydrochloric acid whilst stirring.
When the reaction is concluded after standing for about 12 hours, the insoluble
diazo-compound is filtered off' and introduced into the alkaline solution of a phenol
or into the acetic acid solution of an amine. In order to complete the production
of the colouring matter it is most practical to employ heat, and in case the com-
bination is performed in an acetic acid solution to eventually render the mixture
alkaline by means of soda lye. The colouring matters themselves are isolated by
salting out and filtration.
The manufacture of the new colouring matters may be performed in practice as
follows.
EXAMPLE I.
Colouring matter obtained by combining molecular proportions of tetrazo-
diphenyl salicylic acid, and alpha-naphthylamine and after diazotising combining
the diazo compound with alpha-naphthol-alpha-monosulpho-acid.
28-2 parts by weight of benzidine sulphate are finely suspended in water, mixed
with 564 parts by weight of hydrochloric acid of 21 degrees Baumé and diazotised
by 14 parts by weight of sodium nitrite. The solution of tetrazodiphenyl thus
obtained is then added to an icy cold solution of 14 parts by weight of salicylic
acid that has been rendered alkaline by the addition of sodium carbonate. After
standing for some hours when the reaction is completed a hydrochloric acid solution
of 14.3 parts by weight of alpha-naphthylamine is added to the liquid. The
production of the dye-stuff is completed by heating. The tetrazo-derivative thus
produced is separated by the addition of alkali and the precipitate is filtered off
pressed and dried. It is then suspended in water, mixed with soda lye and a
watery solution of 7 parts by weight of sodium nitrite and hydrochloric acid is
added. As the diazotising progresses, the precipitate which at first is of a brown
black colour, slowly becomes brighter in colour and when after standing for about
12 hours it possesses a brown-red colour the diazocompound is filtered off and
introduced into a solution of 24.6 parts by weight of the sodium salt of alpha-
naphtholmonosulpho acid maintained alkaline. After heating to 80 degrees Centi-
grade the colouring matter which has separated is filtered off and dried.
This product dyes unmordanted cotton in an alkaline bath grey-black shades.
Colouring matter obtained by combining molecular proportions of tetrazodiphenyl
salicylic acid and alpha-amidonaphthol ether and after diazotising with dihydroxy-
naphthalene monosulpho-acid S."
By allowing the diazo-compound obtained according to Example 1. from the
colouring matter (tetrazodiphenylsalicylic acid + alpha amidonaphthol ether)
_corresponding to 7 parts by weight of sodium nitrite to act upon 15 parts of
dehydroxynaphthalene-monosulpho acid S in the aforesaid manner a colouring
matter is obtained which dyes unmordanted cotton Russian green in an alkaline
bath.
Colouring matter resulting by combination of molecular proportions of tetrazo-
diphenyl, salicylic acid, and alpha-naphthylamine and after diazotising with beta-
naphthylamine disulpho acid G.
The diazo-compound of the colouring matter; tetrazodiphenylsalicylic
acid alpha-naphthylamine which is obtained according to Example I. and
corresponds to 7 parts by weight of sodium nitrite, is allowed to act upon.an acetic
acid solution of 34.7 parts by weight of the sodium salt of amido G. acid, the
temperature being slowly raised to 80 degrees Centigrade. By addition of soda

page_text: Dyestuff obtained by combining molecular proportions of tetrazostilbenedisulpho
acid, salicylic acid and alpha-naphthylamine and after diazotising with meta-
phenylenediamine.
The mixed colouring matter; tetrazostilbene disulpho acid + salicylic acid +
alpha-naphthylamine is dissolved in alkali and mixed with the equivalent quantity
of sodium nitrite, the mixture is then cooled to 0 degrees Centigrade and diazotised
by acidulating with hydrochloric acid. After standing for about 12 hours the
resulting diazo-compound is filtered off and added to an acetic acid solution of one
molecular proportion of meta-phenylenediamine. It is then heated to 80 degrees
Centigrade, made alkaline by means of soda lye, and the colouring matter is salted
out and separated by filtration. It dies a brownish black colour.
The shades of the colouring matters obtained according to this process are not
so much dependent on the above mentioned para-diamines as mainly upon the
nature of the dyestuff components employed. Yellowish-brown; brown-black;
olive or Russia green, green or greenish-black colouring matters are obtained by
means of the following components; resorcin alpha-naphthylamine sulpho acid,
alpha-naptholmonosulpho acid (Piria and Cleve), alpha-naphtholdisulpho acid S
(English Specification No. 1577585), alpha-naphtholdisulpho acid (German
Patent 45776), beta-naphtholmonosulpho acid (Schäfer), beta-naphtholdisulpho
acid G R or F, dihydroxynaphthalenemonosulpho-acid G or S, naphtolcarboxylic
acid, dihydroxynaphthalene 1-8, amidonaphthols, amidonaphthol-ether and their
sulpho-acids.
Those products which are derived from the sulpho-acids of the above mentioned
para-diamines yield, in the same manner, with meta-phenylenediamine and its
sulpho acids and likewise with alpha-naphthylamine, alpha and beta-naphthol,
violet to brown-black colouring matters.
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 :-
First. The process for the manufacture of direct dyeing colouring matters by
combining molecular proportions of one of the tetrazo compounds of benzidine,
ortho-tolidine, i diamidophenylorthotolyl, diamidomonoalkyloxydiphenyl, diamido-
monoalkyloxyphenyltolyl, diamidoorthodiphenol-ether, diamidoazo-benzene, diamido-
azoxybenzene, diamidostilbene, diamidoffüorene, diamidonaphalene (alpha-alpha),
diamidocarbazol, diamidodiphenylenoxide, diamidoditolnyleneoxide, para-phenylen-
diamine, the sulphones of benzidine, orthotolidine, and diamidophenylorthotolyl, as
well as the mono- and disulpho-acids of the aforesaid substances either with one
molecular proportion of salicylic acid or meta or orthocresol carboxylic acid and
then with one molecular proportion of alpha-naphthylamine or alpha-amidonaphthol-
ether or at first with alpha-naphthylamine or alpha-amidonaphthol-ether and then
with salicylic acid or cresol carboxylic acid, subsequently diazotising the resulting
amidotetrazo-compounds and combining the new diazotised tetrazo compounds with
amines or phenols or with the sulpho acids of amines or phenols.
Second. The new colouring matters such as are obtained by proceeding as
claimed by the preceding claiming clause.