Year: 1898

page_text: Date of Application (In the United Kingdom), 16th Nov., 1898
Complete Specification Left, 7th July, 1898-Accepted, 12th Aug,, 1899
We, VIDAL FIXED ANILINE DYES LIMITED and LOUIS HAAS, both of Rue Michel
Carré à Argenteuil, (Seine et Oise), in the Republic of France, do hereby declare the
nature of this invention to be as follows:-
This invention relates to a method of preparing new triphenylmethane and
diphenylnaphtylmethane dye-stuffs obtained by the sulphuric condensation of
tetramethylated or tetraethylated diamidobenzhydrols with aromatic hydrazines,
without subsequent oxidation.
Tetramethylated or tetraethylated diamidobenzhydrols have the property, while
undergoing condensation, of combining with various aromatic compounds, such as
bases, phenols and hydrocarbons, whether halogenized or nitrated, and of thus forming
"leuco" bases capable of being converted into colouring matter by being subsequently
oxidized by means of dioxide of lead, chloranil or any other suitable oxidizer.
Now we have found that certain aromatic hydrazines are capable, in the presence
of concentrated sulphuric acid, of combining with hydrols and producing a new
species of colouring agents fit to be used in dyeing, without the aid of any oxidizers.
The condensation is performed at from 60 to 70° (Centigrade), when-in the first
phase of the operation-there will be observed the formation of a leucobase the whole
of which becomes rapidly transformed into colonring matter in loosing 1 molecule of
ammoniac. It should be borne in mind that the sulphuric acid does not in this
instance as might be supposed-act in the way the usual oxidizers do upon
"leuco" bases; for if the "leuco" base be isolated before its transformation and
oxidized by known oxidizing media, it will be found that the resulting colouring
matter will be essentially different from the product obtained in the sulphuric
condensing medium in the second phase.
Thus phenyl hydrazine combines with tetramethylated hydrol to form a "leuco"
base oxidizable to a greenish blue colour, while in the second phase the whole of this

page_text: "leuco" tare ecomes converted in the sulphuric medium into a violet colouring
agent by the loss of 1 molecule of ammoniac,
are dissolved, cold, in 10 parts of concentrated sulphuric acid and heated for about
half an hour to from 60 to 70° (Centigrade). The hydrol disappears, the sulphuric 1
solution assumes an olive colour and the leuco base is formed. Heating is now
continued until the temperature is raised by from 10 to 20° (Centigrade), when the
sulphuric solution will change to a brown colour, and a short time-say about an
hour and a half-after this, the leuco base which was originally oxidizable to a greenish
blue will have changed to a violet colour.
This product is insoluble in water and in alkalies and readily separates by
neutralization from the sulphuric solution diluted in water. It is soluble in hot
diluted acetic acid, changing to a reddish violet; in diluted mineral acids it changes
to a light yellow; in alcohol, to violet; in ether, benzine and ligroin it is insoluble.
It is precipitated from its cold hydrochloric or sulphuric solutions by means of:
acetate of soda.
It will dye wool a violet colour over a slightly acid bath.
(2). By substituting 190 grammes of parasulphophenylhydrazine for the phenyl-
hydrazine in the foregoing example, and operating under the same conditions as
before, a rather more blueish violet-not unlike that of the first example on the
whole will be obtained; but this will be found soluble in diluted caustic alkalies
without undergoing any discoloration. It is separated from its sulphurio solution by
being neutralized with carbonate of soda.
It will dye wool a blueish violet over a slightly acid bath.
(3). By substituting 122 grammes of methylphenylhydrazine for the phenylhydra-
zine instanced in Example No. 1, there will be obtained under the same conditions a
more reddish violet than that of the preceding example, but having similar properties
in other respects.
It will dye wool a reddish violet in a slightly acid bath,

page_text: (4). If in No. 1 example ethylphenylhydrazine be substituted for phenylhydrazine
the result will be a violet colour similar to that obtained from methylhydrazine.
(5). By substituting 182 grammes of diphenylhydrazine for the phenylhydrazine of
No. 1 example, a blue colouring substance will be obtained, which is insoluble in water
and alkalies, but soluble in alcohol and dilute acids, and also soluble in hot dilute
acetic acid where it will turn blue. It will impart a blue shade to wool.
(6). By substituting 237 grammes of 1-4 sulphonaphthylhydrazine for the phenyl-
hydrazine of example No. 1 a blue colouring agent will be obtained, which is insoluble
in alkalies, but soluble to a true blue in dilute acetic acid; into light yellow in dilute
mineral acids; into blue in alcohol; it is insoluble, also, in benzin, ether and ligroin
and may be precipitated from its dilute sulphuric and hydrochloric solutions by
means of acetate of soda.
It will dye wool a deep and bright blue over an acetic bath, and a somewhat more
greenish blue over a slightly sulphuric bath. The dyes it gives offer a certain amount
of resistance to alkalies.
(7). If 317 grammes of bisulphonated a-naphthylhydrazine (a derivative from
Dahl's acid mixtures II and III) for the phenylhydrazine of No. 1, a blue dye-stuff of
a rather more greenish shade than that of the preceding example and of the same
degree of solubility will be obtained.
It is to be noted that in the naphthaline series the presence of the SO, H group
appears to assist the re-action.
a-naphthylhydrazine will only partially change to a blueish-green colouring matter,
while B-naphthylhydrazine somewhat more readily turns into a green dyestuff.
Also, in all the examples above given the tetramethyldiamidobenzhydrol may
be replaced by its tetraethyl homologue without making any change in the conditions
under which the operation is carried on. The corresponding products are similar (to
those described above) in nature, shade of colouring and properties.
Dated this 18th day of November 1898
Improvements in the Manufacture of Colouring Matters.
We, VIDAL FIXED ANILINE DYES LIMITED and LOUIS HAAS, both of Rue Michel
Carré à Argenteuil (Seine et Oise), in the Republic of France, 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 :-
This invention relates to a method of preparing new triphenylmethane and
diphenylnaphtylmethane dye-staffs obtained by the sulphuric condensation of tetra-
methylated or tetraethylated diamidobenzhydrols with aromatic hydrazines, without
subsequent oxidation.
Tetramethylated or tetraethylated diamidobenzhydrols have the property, while
undergoing condensation, of combining with various aromatic compounds, such as
bases, phenols and hydrocarbons, whether halogenized or nitrated, and of thus forming
"leuco" bases capable of being converted into colouring matter by being subsequently
oxidized by means of dioxide of lead, chloranil or any other suitable oxidizer.
Now we have found that certain aromatic hydrazines are capable, in the presence
of concentrated sulphuric acid, of combining with hydrols and producing a new species
of colouring agents fit to be used in dyeing, without the aid of any oxidizers.

page_text: DESCRIPTION.
The condensation is performed at from 60 to 70° (Centigrade), when-in the first
phase of the operation-there will be observed the formation of a leucobase the whole
of which becomes rapidly transformed into colouring matter in loosing 1 molecule of
ammoniac. It should be borne in mind that the sulphuric acid does not in this
instance as might be supposed-act in the way the usual oxidizers do upon ❝ leuco"
bases; for if the "leuco" base be isolated before its transformation and oxidized by
known oxidizing media, it will be found that the resulting colouring matter will be
essentially different from the product obtained in the sulphuric condensing medium
in the second phase.
Thus phenyl hydrazine combines with tetramethylated hydrol to form a "leuco".
base oxidizable to a greenish blue colour, while in the second phase the whole of this
"leuco" base becomes converted in the sulphuric medium into a violet colouring
agent by the loss of one molecule of ammonia.
and Tetramethyldiamidobenzhydrol
270 "
are dissolved, cold, in 10 parts of concentrated sulphuric acid and heated for about
half an hour to from 60 to 70° (Centigrade). The hydrol disappears, the sulphuric
solution assumes an olive colour and the leuco base is formed. Heating is now
continued until the temperature is raised by from 10 to 20° (Centigrade), when the
sulphuric solution will change to a brown colour, and a short time-say about an hour
and a half after this, the leuco base which was originally oxidizable to a greenish blue
will have changed to a violet colour,
This product is insoluble in water and in alkalies and readily separates by neutrali-
zation from the sulphuric solution diluted in water. It is soluble in hot diluted
acetic acid, changing to a reddish violet; in diluted mineral acids it changes to a
light yellow; in alcohol, to violet; in ether, benzine and ligroin it is insoluble. It is
precipitated from its cold hydrochloric or sulphuric solutions by means of acetate of
Boda.
It will dye wool a violet colour over a slightly acid bath.

page_text: (2). By substituting 190 grammes or parasulphophenyl-hydrazine for the phenyl-
hydrazine in the foregoing example, and operating under the same conditions as
before, a rather more blueish violet-not unlike that of the first example on the
whole will be obtained; but this will be found soluble in diluted caustic alkalies
without undergoing any discoloration. It is separated from its sulphuric solution by
being neutralized with carbonate of soda,
(3). By substituting 122 grammes of methylphenylhydrazine for the phenyl-
hydrazine instanced in Example No. 1, there will be obtained under the same
conditions a more reddish violet than that of the preceding example, but having
similar properties in other respects.
It will dye wool a reddish violet in a slightly acid bath.
(4). If in No.1 example ethylphenylhydrazine be substituted for phenyl.
hydrazine the result will be a violet colour similar to that obtained from methyl-
hydrazine.
(5). By substituting 182 grammes of diphenylhydrazine for the phenylhydrazine
of No. 1 example, a blue colouring substance will be obtained, which is insoluble
in water and alkalies, but solable in alcohol and dilute acids, and also soluble in
hot dilute acetic where it will turn blue. It will impart a blue shade to wool.
(6). By substituting 237 grammes of 14 sulphonaphthylhydrazine for the
phenylhydrazine of example No. 1 a blue colouring agent will be obtained, which
is insoluble in alkalies, but soluble to a true blue in dilute acetic acid; into light
yellow in dilute mineral acids; into blue in alcohol; it is insoluble, also, in benzin,
ether and ligroin and may be precipitated from its dilute sulphuric and hydro-
chloric solutions by means of acetate of soda.
It will dye wool a deep and bright blue over an acetic bath, and a somewhat
more greenish blue over a slightly sulphuric bath. The dyes it gives offer a certain
amount of resistance to alkalies.
(7). If 317 grammes of bisulphonated a-naphthylhydrazine (a derivative from
Dahl's acid mixtures II and III) for the phenylhydrazine of No. 1, a blue dye-stuff of
a rather more greenish shade than that of the preceding example and of the same
degree of solubility will be obtained.
It is to be noted that in the naphthaline series the presence of the 80,H group
appears to assist the reaction. a-naphthylhydrazine will only partially change to a
blueish-green colouring matter, while s-naphthylhydrazine somewhat more readily
turns into a green dyestuff.
Also, in all the examples above given the tetramethyldiamidobenzhydrol may be
replaced by its tetraethyl homologue without making any change in the conditions
under which the operation is carried on. The corresponding products are similar
(to those described above) in nature, shade of colouring and properties.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:-
(1) As novel products violet, blue, and greenish blue colouring agents for dyeing
animal fibre, as hereinabove described.
(2) As a novel process, the prolonged action of concentrated sulphuric acid at
from 60° to 80° upon a mixture of equal molecules of tetralcoylhydrols and hydra-
zines derived from:
Aniline, monomethyl monoethyl-aniline and diphenylamine, parasulphanilic.
1.1 monthionin and hisntphonic nenhthylamina Dahl II and Dahl III
Dated this 7th day of July 1899.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.