Improvements in the Manufacture of Colouring Matters.
Year: 1890

page_text: Date of Application, 27th May, 1890
Complete Specification Left, 25th Mar., 1891-Accepted, 25th Apr., 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by Messrs. WIRTH & Co., of Frankfort-on-the-Main,
acting as Agents of A. Leonhardt & Co., of Mulheim, near Frankfort-on-the-
Main, both in the Empire of Germany.]
Improvements in the Manufacture of Colouring Matters.
I, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake & Co., Patent
Agents, 45, Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention to be as follows:-
The object of the present invention is the production of orange dye-stuffs of the
acridine series of the general formula.
IN WHICH I Sigm
series (methyl, ethyl etc.)
These dye stuffs are produced from tetramido compounds of the formula
R¹
C¹H
-
NR, CH
CH, - NR,
NHANH,
which by the elimination of ammonia and oxydation are transformed into colouring
matters. The tetramido compounds mentioned can be produced from aldehydes
(for instance formaldehyde benzoldehyde) and substituted aromatic meta diamines
(for instance metamido-dimethyl-aniline).
We have further found that in some cases aldehydes can also be condensed with
tertiary aromatic amines and transformed into tetramido compounds by nitration
and reduction of the obtained binitro substituted products.
Instead of forming first leucobodies from aldehydes and substituted aromatic
metadiamines as above stated and oxidizing them, colouring matters can also be
obtained by the direct heating of the acids corresponding with the aldehydes, with
diamines.
Dated this 27th day of May 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Colouring Matters.
I, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake & Co., Patent
Agents, 45, Southampton Buildings, in the County of Middlesex, 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 the production of new orange colouring matters derived
from acridine.

page_text: These colouring matters can be produced by eliminating ammonia from tetramido-
derivatives of the general formula,
1
LTE-TD1
in which R' signifies hydrogen or an organic radical such as phenyl, and R a radical
of the fatty series such as methyl or ethyl; and oxydizing the leuco-compounds
thus obtained.
The above mentioned tetramido derivatives can be manufactured by condensing
aldehydes such as formaldehyde or benzaldehyde, or its substitutes, with aromatic
substituted metadiamines, such as meta amido-dimethyl-aniline or the like. Another
way of producing these tetramido-compounds consists in first condensing aldehydes
with tertiary aromatic amines, such as dimethyl-aniline and then introducing the
two other amido-groups by nitration and reduction.
The elimination of ammonia is best effected by heating the tetramido-compounds
with mineralic acids, such as hydrochloric or sulphuric acid. The oxydation can
be carried out with most of the commonly used oxydizing agents (sesquichloride of
iron being the best) and even with the oxygen of the atmosphere.
Instead of first forming leuco bodies from formaldehyde and substituted aromatic
metadiamines and then oxydizing them, colouring matters can also be obtained by
a direct heating of the acid corresponding with formaldehyde, viz. :-formic acid, or
a mixture of oxalic acid and glycerine with aromatic metadiamines in the presence
of a suitable condensing agent.
The new orange basic dyestuffs thus obtained are capable of dyeing or printing
mordanted cotton in orange shades, silk dyed therewith shows in most cases a
brilliant greenish fluorescence.
The following explanation will show in what manner the invention can be carried
into practice.
First. 10.6 kilos of benzaldehyde 27 kilos of metamido-dimethylaniline and
24 kilos. of muriatic acid, of 30% are heated in an alcoholic solution at the reflux
cooler, until a sample dissolves completely or nearly so in water and the aldehyde
has disappeared. The whole mass is then diluted with water and filtered if
necessary and the product of condensation (tetramethyltetramidotriphenylmethan)
is precipitated from the solution by carbonate of soda or ammonia or the like,
15 kilos of this product are then heated with 30 kilos of muriatic acid (30 %) and
60 litres of water in an autoclave for several hours to a temperature of about 150°
Centigrade. After cooling down the product of the reaction containing the leuco-
compound is dissolved in dilute hydrochloric acid and is oxydized with a solution of
sesquichloride of iron (Fe,Cl). After standing for some time when the formation
of colouring matter is finished, the latter is precipitated by chloride of zinc and can
be purified by dissolving in water, filtering and precipitating again.
Second. 10-6 kilos of benzaldehyde 30 kilos of metaamido-dimethylorthotoluidine
10 kilos of concentrated sulphuric acid and 100 litres of spirit are heated at the
reflux cooler for some time. Thus the sulphate of tetramethyltetramidoditolyl-
phenylmethan separates being nearly insoluble in spirit. It is converted into
colouring matter by heating with dilute hydrochloric acid or dilute sulphuric acid
and afterwards oxydizing in a manner similar to that above indicated under 1st.
When I dissolve the sulphate just mentioned in 10 parts of concentrated sulphuric
acid, and nitrate it in the cold with the calculated quantity of strong nitric acid
(diluted with sulphuric acid) I obtain mononitrotetramethyltetramidoditolyl-
phenylmethan which can be separated from the solution of its salts by soda lye or
the like forming a yellow precipitate. Another way to prepare a mononitro-
compound consists in heating for some time say 15 kilos of paranitrobenzaldehyde,
3 kilos of metaamidodimethylorthotoluidine 1 kilo of concentrated sulphuric acid:

page_text: and 10 litres of spirit at the reflux cooler when the sulphate of the mononitro--
compound will gradually separate from the solution.
This mononitro-compound when transformed into orange colouring matter as
stated above yields a dye stuff' of weak basic properties, I prefer therefore to
reduce this mononitro compound say with protochloride of tin and hydrochloric acid
or with zinc dust and hydrochloric acid, in order to obtain the amido-derivative
which can be separated in a way well known to chemists forming white flakes when
precipitated with soda lye. This amido-derivative when heated with one part by
weight of concentrated sulphuric acid and 12 parts by weight of water for 6 hours
to a temperature of 1300-140° C. yields a leuco-compound from which an orange
colouring matter can be obtained by oxydizing with sesquichloride of iron and
precipitating with acetate of soda and chloride of zinc, the colouring matter thus
obtained being easily soluble in water.
Third. 14 kilos of metaamido-dimethylaniline are dissolved in 30 litres of spirit
and 5 litres of concentrated hydrochloric acid. To this solution I add in the cold
state 3.5 litres of a watery solution of formaldehyde of 40%. In this way tetra-
methyltetramidodiphenylmethan is formed which separates by adding an alcoholic
solution of 6 kilos of acetate of sodium. It is then heated as usual with dilute
hydrochloric acid to a temperature of 140° C. and the leuco-compound is oxydized
with sesquichloride of iron.
Fourth. 2.5 kilos of tetramethyldiamidodiphenylmethan are dissolved in 35 kilos
of concentrated sulphuric acid and nitrated in the cold with about 2 kilos (two
molecules) of nitric acid of 40° Baumé (previously diluted with sulphuric acid).
After standing some time the whole liquid is poured into 250 litres of cold water
and the binitro-compound is reduced by gradually adding about 8 kilos of zinc dust,.
the mass being well agitated during the reduction. It is then filtered and the
filtrate is boiled down and finally heated for some time to about 140° C. By thus
operating, oxydation is effected by means of the oxygen of the atmosphere. After
cooling I dissolve the whole mass in water and precipitate the dyestuff by means of
common salt.
Instead of boiling down the product of reduction the tetramido derivative
contained therein can be precipitated from the solution by an excess of soda lye and
afterwards heated with about 4 parts of dilute hydrochloric acid in a closed vessel
for some time to a temperature of 140° C. In this case it will be necessary in order
to transform the whole into colouring matter to employ some oxydizing agent,
sesquichloride of iron being the best for this purpose.
In an analogous way I obtain an orange colouring matter by employing tetra-
ethyldiamido-diphenylmethan instead of the methyl derivative.
Fifth. A mixture of 12 kilos of metaamido-dimethylaniline 12 kilos of
dehydrated oxalic acid 10 kilos of glycerine and 10 kilos of chloride of zinc is.
gradually heated up to about 150° C. while being well stirred, and kept at this
temperature for some hours. When the formation of orange colouring matter is
finished the melt after some cooling is dissolved in acidulated water and the
colouring matter is precipitated with common salt.
In the same way I prepare orange colouring matter by employing metaamido-
diethylaniline or meta amidomonoethylaniline instead of the methyl derivative.
Having now particularly described and ascertained the nature of the said
invention, 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 :-
First. A process of producing substituted tetramido bases which process consists
in condensing formaldehyde with metaamido-dimethylaniline or benzaldehyde with
metaamido-dimethylaniline or benzaldehyde or paranitrobenzaldehyde with meta-
amido-dimethylorthotoluidine; or consists in nitrating and reducing tetramethyl or
tetraethyl-diamidodiphenylmethan, all substantially as hereinbefore described.
Second. A process of producing mononitrotetramethyltetraamido-ditolylphenyl-

page_text: methan which process consists in nitrating tetramethyltetramido-ditolylphenylmethan
substantially as hereinbefore described.
Third. A process of producing amidotetramethyltetramidoditolylphenylmethan,
which process consists in reducing nitrotetramethyltetraamido-ditolylphenylmethan,
substantially as hereinbefore described.
Fourth. The new bases produced according to the foregoing Claims 1st 2nd 3rd.
Fifth. The process of producing basic orange colouring matter which process
consists in heating substituted tetramido bases such as tetramethyl tetramido-
diphenylmethan or tetraethyltetramido-diphenylmethan, or tetramethyltetramido-
triphenylmethan, or tetramethyltetramido-ditolylphenylmethan or the amido
derivative of the latter with mineralic acids at an elevated temperature and oxy-
dizing the leuco compounds thus formed, substantially as hereinbefore described.
Sixth. The process of directly producing basic orange colouring matters which
process consists in melting meta-amido-dimethylaniline or metaamido-diethylaniline
or metaamidoethylaniline with formic acid (or a mixture of oxalic acid and
glycerine) in presence of a suitable condensing agent, substantially as hereinbefore
described.
Seventh. The new basic orange colouring matters produced according to the
processes set forth and pointed out by the foregoing Claims 5 and 6.
Dated this 25th day of March 1891.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.