Production of Substantive Trisazo Colouring Matters.
Year: 1896

page_text: Date of Application, 16th Dec., 1896-Accepted, 23rd Jan., 1897
[Communicated from abroad by THE CHEMICAL WORKS, formerly SANDOZ, of
Basel, Switzerland, Chemical Manufacturers.]
Production of Substantive Trisazo Colouring Matters.
I, WILLIAM EDWIN HEYS of 70 Market Street Manchester in the County of
Lancaster, Patent Agent, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
For the production of substantive trisazo colouring matters, the tetrazo compounds
of para-diamines have been frequently combined in molecular proportions with
amines and the intermediate products thus obtained have been re-diazotised. The
new tetrazo compounds so produced have been combined with two molecules of
an azo component. The amines proposed as suitable for this purpose have been
alpha-naphthylamine, Clève's alpha-naphthylamine sulphonic acids, and a number
of amidonaphthol sulphonic acids. Hitherto however, it has been found possible
to replace these compounds by ordinary amines of the benzene series, and it has
been experimentally proved that by the process hereinbefore referred to, no
amido-azo compounds capable of further diazotisation were formed, but only
diazo-amido compounds.
My foreign correspondents however have discovered that the easily accessible
para-xylidine (CH, NH, CH, = 1:2:4), proves to be an exception to this rule,
since the intermediate products obtained from one molecule of a tetrazo compound
and one molecule of para-xylidine can be readily diazotised and be further combined
without decomposition. Of the colouring matters prepared in this manner, the
products obtained by acting with the rediazotised bodies on two molecules of an
amidonaphthol sulphonic acid have proved to be most valuable. On using, for
example, amidonaphthol disulphonic acid H, colouring matters are obtained which
dye, without mordants, shades varying from intense indigo to a greenish blue, and
which are capable of diazotisation on the fibre and of producing thereon, by
combination with beta-naphthol, deep black shades perfectly fast to washing.
Hitherto, only dark blue shades have been obtained in this manner by the
diazotisation of known colouring matters on the fibre, and to produce a full black,
the more expensive diamine developers, or mixtures of beta-naphthol and resorcinol
have had to be used.
In carrying out this invention the following mode of operation may be
employed.
EXAMPLE.
9.2 kilos. of benzidine are diazotised in the well known manner and a solution
of 61 kilos. of para-xylidine in 80 litres of water and 6 kilos. of hydrochloric
acid 21 Bè. is added at a temperature of about 5° C. to the clear tetrazo solution.
The mixture is stirred for about two hours, when a part of the intermediate product
separates as a brown precipitate. To complete the reaction, a solution of 20 kilos.
of crystallised sodium acetate is added, and the mixture, after a thorough stirring,
is allowed to remain for about 10 hours at a temperature not exceeding 5° C. It
is then acidulated with 25 kilos. of hydrochloric acid 21 Bè. and diazotised by the
gradual addition of a solution containing 3-5 kilos. of sodium nitrite. The brownish

page_text: black precipitate is completely dissolved during this operation with an intensely
reddish yellow colour. The resulting solution is then allowed to act on a solution
of 34.5 kilos. of amidonaphthol disulphonic acid H, (acid sodium salt of 100%),
in 600 litres of water, 4-5 kilos. of caustic soda, and 40 kilos. of sodium carbonate.
The mixture is allowed to stand for 12 hours and is then heated to boiling. The
colouring matter is afterwards salted out, filtered and dried in the usual way. It
dyes unmordanted cotton, from a bath containing common salt, intense indigo
shades. When diazotised on the fibre, and combined with beta-naphthol, a deep
black is produced. When combined in a similar way with meta-phenylene or
with tolylenediamine, a greenish black, and with resorcinol, a dark green are
produced.
In an analogous manner, trisazo colouring matters are obtained which contain,
as final components, two molecules of another amidonaphthol sulphonic acid.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondents, I declare that what I claim is :-
1. The berein before described process for the manufacture or production of
substantive trisazo colouring matters which consists in combining one molecule of
a tetrazo compound of a para-diamine with one molecule of a para-xylidine to form
intermediate products, in rediazotising these intermediate products and in combining
the thus produced tetrazo compounds with two molecules of an amidonaphthol
sulphonic acid, substantially as herein before described.
2. As new substances, the new substantive trisazo colouring matters produced
by the process claimed in the first claim, substantially as herein before set forth.
Dated this 15th day of December A.D. 1896.
WILLIAM E. HEYS.