Year: 1888

page_text: Date of Application, 30th Oct., 1888
Complete Specification Left, 8th Jan., 1889
Complete Specification Accepted, 16th Feb., 1889
I, HENRY HARINGTON LEIGH, Fel. Inst. P.A., Assoc. M. Inst. C.E., practising as
Phillips & Leigh, of No. 22, Southampton Buildings, Chancery Lane, in the County of
Middlesex, Engineer and Patent Agent, do hereby declare the nature of this invention
to be as follows:-
:-
My invention relates to a process for the production of coloring matters by com-
bining one molecule of tetrazo diphenyl or its homologues with two molecules of a
sulpho acid of diazo-amido-benzene or its homologues, and the subsequent substitution
of two molecules of an amine or a phenol for the two molecules of the diazo-amido-
benzene-sulpho acid or its homologues employed.
So called "mixed colors" can be produced by combining one molecule of tetrazo
diphenyl or its homologues with two molecules of a sulpho acid of diazo-amido-benzene
or its homologues and the subsequent substitution of, first, one molecule of an amine
or a phenol for one molecule of the diazo-amido-benzene-sulpho acid or its homologues,
and afterwards the substitution of another molecule of a different amine or phenol for
the remaining molecule of the diazo-amido-benzene-sulpho acid or its homologues.
By amines I mean the following:
(a.) Aniline and its homologues.
The naphthylamines.
Ethylated or methylated aniline or its homologues.
(b.) Sulpho acids of amines mentioned under (a), such as sulphanilic acid, and the
naphthylamine sulpho acid.
By phenols I mean the following
(c.) Monotomic phenols, such as, phenol and creosole; and the naphthols.
(d). Diatomic phenols, such as, resorcin, orcin, di-oxy-naphthalene.
(e.) Sulpho acids of the phenols mentioned under (c) and (d), such as, beta-
naphthol-disulphonic acid, resorcin sulphonic acid.

page_text: 28 lbs. of benzidine sulphate or its equivalent of the base, are converted in the usual
and well known manner into tetrazo diphenyl chloride and this solution is run into
60 lbs. of the soda salt of the sulpho acid of diazo-amido-benzene and 60 lbs. of acctate
of soda dissolved in 50 gallons of water.
The compound formed separates in brown flocks and the product is kept stirred for
about an hour and a half when the reaction is complete. It is then run into a solution
of 55 lbs. of naphthionate of soda and 60 lbs. of acetate of soda dissolved in 200 gallons
of water. During this operation and for 12 hours afterwards the mixture should be
constantly stirred. The color is then filtered off and converted into its soda salt.
Alkalies may be used instead of acetate of soda to effect the combination of the tetrazo
diphenyl with the diazo-amido-benzene sulphonic acid, and the acetato of soda used in
conjunction with the naphthionate may also be replaced with alkalies.
If the benzidine in Example I be replaced by tolidine and one of the two molecules
of the naphthionate of soda be replaced by a molecule of resorcin, Congo 4 R is
produced.
EXAMPLE V.
If in the place of the naphthionate of soda in Example I, 35 lbs. of the soda salt of
di-sulphonic acid of beta-naphthylamine be used and then after the lapse of about 10
hours 24 lbs. of the soda salt of the mono-sulpho acid of beta-naphthylamine be added
in solution, a red coloring matter is produced which resists the action of dilute acids.
I have observed that when tetrazo ditolyle is used in the place of tetrazo diphenyl.
the compound formed with the diazo-amido-benzene sulpho acid is much more stable
and is not attacked by naphthionic acid readily at low temperatures; it is therefore
sometimes necessary to raise the temperature to about 40° C. to complete the reaction.
All the coloring matters produced by the above process have the property of dyeing
unmordanted cotton in an alkaline or soap bath.
Dated this 30th day of October 1888.

page_text: COMPLETE SPECIFICATION.
Improvements in the Process for the Manufacture of Azo Colouring
Matters.
1, HENRY HARINGTON LEIGH, Fel. Inst. P.A., Assoc. M. Inst. C.E., practising as
Phillips & Leigh, of No. 22 Southampton Buildings, Chancery Lane, in the County
of Middlesex, Engineer and Patent Agent, do hereby declare the nature of this
invention, as the same has been communicated from abroad, and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
My invention relates to a process for the production of coloring matters, by
combining one molecule of tetrazo diphenyl or its homologues with two molecules of
a sulpho acid of diazo-amido-benzene or its homologues, and the subsequent substitution
of two molecules of an amine or a phenol for the two molecules of the diazo-amido-
benzene-sulpho acid or its homologues employed.
So called "mixed colors' can be produced by combining one molecule of tetrazo-
diphenyl or its homologues, with two molecules of a sulpho acid of diazo-amido-benzene
or its homologues, and the subsequent substitution of, first one molecule of an amine
or a phenol, for one molecule of the diazo-amido-benzene-sulpho acid or its homologues,
and afterwards the substitution of another molecule of a different amine or phenol
for the remaining molecule of the diazo-amido-benzene-sulpho acid or its homologues.
By amines mean the following:-
(a). Aniline and its homologues :
The naphthylamines:
Ethylated, or methylated aniline or its homologues :
(b). Sulpho acid of amines mentioned under (a) such as, sulphanilic acid, and the
naphthylamine sulpho acids.
By phenols I mean the following
:--
(c). Monotomic phenols, such as phenol and cresole; and the naphthols:
(d). Diatomic phenols; such as resorcin, orcin, di-oxy-naphthalene:
(e). Sulpho acids of the phenols mentioned under (c) and (d) such as beta-
naphthol-disulphonic acid, resorcin sulphonic acid.
I am aware of the English Patent No. 6687, May 6th 1887 of C. D. Abel (a
coummunication from the Acetien-Gesellschoft für Anilin-fabrikation) in which the
combination of the sulpho acids of amido-azo-benzene with tetrazo diphenyl and its
homologues, and the subsequent replacement of the sulpho acids by amines and phenols
is claimed.
As in both processes-bis and nine-the sulpho acids of amido-azo-benzene and
those of diazo-amido-benzene are replaced, the ultimate products-where for instance
naphthionic acid is used-are the same as the color known commercially as
Congo
Rad
66

page_text: amido-azo-benzene sulpho acid which Abel uses, is established very easily by a
-comparison of the chemical and physical properties of the diazo-amido-benzene and
the amido-azo-benzene from which they are respectively derived.
Diazo-amido-benzene melts at 96° C. and explodes at from 150°-200° C.
Amido-azo-benzene melts at 126° C. and distils at 360° C.
Diazo-amido-benzene is insoluble in hot water.
Amido-azo-benzene is partly soluble in hot water.
Diazo-amido-benzene is very soluble in hot alcohol, and in all proportions in ether.
Amido-azo-benzene is only moderately soluble in alcohol or ether.
Diazo-amido-benzene acts only as a base towards H, Pt Cl, and Ag NO, (Watts
VI. 460).
Amido-azo-benzene is a much stronger base and forms well defined salts with acids.
The sulpho acids of amido-azo-benzene are dye stuffs in themselves. This is not
the case with the sulpho acids of diazo-amido-benzene.
As amido-azo-benzene is ordinarily prepared from diazo-amido-benzene, the
advantage of using the sulpho acid of the latter in place of the former is obvious.
The following are examples of how I practically produco coloring matters by my
process:-
Example 128 pounds of benzidine sulphate, or its equivalent of the base are
converted in the usual and well known manner into tetrazo diphenyl chloride, and this
solution is run into 60 pounds of the soda salt of the sulpho acid of diazo-amido-benzene
and 60 pounds of acetate of soda dissolved in 50 gallons of water.
The compound formed separates in brown flocks and the product is kept stirred
for about an hour and a half, when the reaction is complete. It is then run into a
solution of 55 pounds of naphthionate of soda and 60 pounds of acetate of soda
dissolved in 200 gallons of water. During this operation, and for 12 hours afterwards,
the mixture should be constantly stirred. The color is then filtered off and converted
into its soda salt. Alkalies may be used instead of acetate of soda to effect the
combination of the tetrazo diphenyl with the diazo-amido-benzene-sulphonic acid, and
the acetate of soda used in conjunction with the naphthionate may also be replaced
with alkalies.
Example II. If 31-2 pounds of tolidine-sulphate, or its equivalent of the base,
are employed in the place of the benzidine in Example I, the color known commercially
as "Benzo Purpurine" is obtained.
Example III 49-2 pounds of the soda salt of the mono-sulpho-acid of alpha
naphtol be substituted for the naphthionate of soda in Example II, a red-blue
results.
Example IV. If the benzidine in Example I be replaced by tolidine and one of
the two molecules of the naphthionate of soda be replaced by a molecule of resorcine,
Congo 4 R is produced.
Example V. If in the place of the naphthionate of soda in Example I, 35 pounds
of the soda salt of disulphonic acid of beta-naphthylamine be used, and then after
the lapse of about 10 hours, 24 pounds of the soda salt of the mono-sulpho-acid of
beta-naphthylamine be added in solution, a red coloring matter is produced which
resists the action of dilute acids.
I have observed that when tetrazo ditolyle is used in the place of tetrazo diphenyl,
the compound formed with the diazo-amido-benzene-sulpho-acid is much more stable,
and is not attacked by naphthionic acid readily at low temperatures. It is therefore
sometimes necessary to raise the temperature to about 40° C. to complete the reaction.
All the coloring matters produced by the above process have the property of
dying unmordanted cotton in an alkali or soap bath.
· 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,
1st. The herein described process for the production of azo coloring matters by
combining one molecule of tetrazo diphenyl or its homologues with two molecules

page_text: of a sulpho acid of diazo-amido-benzene or its homologues, and the subsequent
substitution of two molecules of an amine or phenol for the two molecules of the
diazo-amido-benzene-sulpho acid or its homologues employed, substantially as set forth.
2nd. The herein described process for the production of azo coloring matters by
combining one molecule of tetrazo diphenyl or its homologues with two molecules of
a sulpho acid of diazo-amido-benzene or its homologues, and the subsequent substitution
of, first, one molecule of an amine or a phenol for one molecule of the diazo-amido-
benzene-sulpho-acid, or its homologues, and afterwards the substitution of another
molecule of a different amine or phenol for the remaining molecule of the diazo-
amido-benzene-sulpho-acid or its homologues employed, substantially as set forth.
Dated this 9th day of January 1889.
HENRY H. LEIGH.