Improvements in and relating to the Production of Coloring Matters.
Year: 1896

page_text: Improvements in and relating to the Production of Coloring Matters.
A communication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE
anciennement GILLIARD P. MONNET ET CARTIER, of Lyons, France, Manufacturers.
I, GEORGE BELOE ELLIS of the Firm of J. C. Mewburn and Ellis of 55 and
56 Chancery Lane in the County of London, Chartered Patent Agents, do hereby
declare the nature of this invention to be as follows:-
By the condensation of phenols, especially resorcinol with the anhydrides of phtalic
acid, succinic acid or such like acids containing two carboxylic groups, a large number
of very valuable coloring matters have been produced, specially distinguished by their
dyeing and fluorescent qualities.
According to the present invention a new series of analogous dyestuffs are produced
by the condensation of resorcinol and other phenols with the anhydride of
ortho-sulphamine-benzoic acid, commonly known as saccharine, in which the second
carboxyl group of phtalic acid is replaced by a sulphonyl radicle.
Remsen (American Chemical Journal VI. page 180) found that on heating ortho-
sulpho-benzoic acid with resorcinol a compound was produced soluble in alkalies with
yellow color and green fluorescence analogous to that of fluorescein. A closer study
of the subject by Remsen and his pupils (American Chemical Journal IX. page 372;
XI, page 73) has shown that the direct product of condensation is a colorless substance
of the formula

page_text: the mass at first liquefies, then thickens and becomes yellow in color.
After seven
hours heating the melt forms a thick paste. It is then allowed to cool and a hard
brittle mass is obtained, which is powdered and treated with a cold dilute solution of
carbonate of soda. A reddish-brown substance remains undissolved, which is soluble
in hot alkalies, but nearly insoluble in the cold, the composition of which has not yet
been determined.
The alkaline solution thus obtained is of deep orange-yellow color, and when diluted
possesses a very strong green fluorescence. The coloring matter can be precipitated
with acid and may be dissolved in alcohol and reprecipitated with water for purification.
After decantation, washing and drying, a brown resinous product exhibiting a green
reflection is obtained which dissolves in alkalies with yellow color and green fluorescence,
is insoluble in water and very soluble in alcohol. To this product the name saccharo-
fluorescein has been given. It may be obtained in a pure crystalline state by
the foliowing treatment.
PREPARATION OF ACETYLATED SACCHARO-FLUORESCEIN.
The brown resinous coloring matter is heated to boiling with three times its weight.
of acetic anhydride in a vessel furnished with reflux condenser. It is then allowed
to cool and poured into a sufficient quantity of alcohol to decompose the excess of
acetic anhydride. The acetylated derivative is precipitated in the form of a finely
crystalline powder slightly yellow in color, which is filtered and washed with alcohol.
When purified by dissolving in glacial acetic acid and reprecipitated with alcohol it
melts about 286° C. It is insoluble in water and in alcohol, soluble in warm glacial
acetic acid. Warmed in an aqueous solution of caustic soda ii colors the solution yellow
with intense green fluorescence. By alcoholic solutions of alkalies it is completely
saponified.
"The regeneration of pure saccharo-fluorescein from the acetylated derivative may
be effected by boiling with an alcoholic solution of caustic soda. When all is dissolved,
the solution is diluted with much water, filtered and acidified with acetic acid.
Saccharo-fluorescein crystallizes out in delicately colored salmon flakes. The product
thus obtained is insoluble in water, but readily soluble in alcohol from which it may
he crystallized. It melts between 265° and 267° C. It dissolves in dilute alkalies
with a very pure yellow color and green fluorescence. Acids precipitate it from this
solution in orange-yellow flocks.
The condensation of saccharin with resorcinol can also be carried out in the presence
of condensation agents such as the chlorides of aluminium or zinc, or sulphuric acid,
but although the reaction takes place with greater rapidity, the product is more
difficult to purify,
Halogen derivatives of saccharo-fluorescein may be prepared in the following
manner: Ten parts by weight of saccharo-fluorescein are dissolved in 50 parts by
weight of alcohol, and 11 parts by weight of bromine added gradually, the temperature
being maintained about 40° C. After all the bromine has been added, three parts by
weight of chlorate of soda dissolved in an equal weight of water is added and the whole
boiled, for half an hour in a vessel with reflux condenser. After addition of the
chlorate, the bromine compound begins to precipitate out in the form of small reddish-
brown crystals. The solution is cooled, the precipitate filtered off and washed with
alcohol. A crystalline powder is thus obtained insoluble in water and alcohol. It
dissolves in alkalies with a fine red color and has similar properties to eosine but a
more bluish nuance.
The iodo-saccharo-fluorescein prepared in a similar manner to the bromine deriva-
tive is a reddish yellow powder which dissolves in alkalies with a fine violet-red
color.
Dated this 24th day of September 1896.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to the Production of Colouring Matters
A cominunication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE,
anciennement GILLIARD P. MONNET ET CARTIER, of Lyons, France, Manufacturers.
I, GEORGE BELOE ELLIS of the firm of J. C. Mewburn & Ellis, of 55 and
56 Chancery Lane in the County of London, Chartered Patent Agents, 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:-
By the condensation of phenols, especially resorcinol, with the anhydrides of
phtalic acid, succinic acid, or such like acids containing two carboxylic groups, a large
number of very valuable coloring matters have been produced, specially distinguished
by their dying and fluorescent qualities.
According to the present invention a new series of analogous dyestuffs are produced
by the condensation of resorcinol and other phenols with the anhydride of
ortho-sulphamine benzoic acid, commonly known as saccharin, in which the second
carboxyl group of phtalic acid is replaced by a sulphonyl radicle.
Remsen (American Chemical Journal VI page 180) found that on heating
ortho-sulpho-benzoic acid with resorcinol a compound was produced soluble in
alkalies with yellow colour and green fluorescence analagous to that of fluorescein. A
closer study of the subject by Remsen and his pupils (American Chemical Journal IX
page 372; XI page 73) has shown that the direct product of condensation is a
colorless substance of the formula
and that this compound when heated for several hours at 185°C. decomposed into
ortho-sulpho-benzoic acid and a coloring matter for which Remsen suggested the
formula
CH
CH, OH₂
CH₂OH
SO2
This coloring matter however could not be obtained crystalline, and analysis proved
it to be an impure or indefinite product.
The manner in which this invention may be carried into effect is as follows:-
22 parts by weight of resorcinol are heated together with 18, parts of weight of pure
saccharin preferably for 7 hours at 200° to 220° C.; the mass at first liquefies, then
thickens and becomes yellow in color. After seven hours heating the melt forms a
thick paste. It is then allowed to cool and a hard brittle mass is obtained which is
powdered and treated with a cold dilute solution of carbonate of soda.
A reddish-brown substance remains undissolved, which is soluble in hot alkalies,
but nearly insoluble in the cold, and the composition of which has not yet been
determined.
The alkaline solution obtained as above stated with carbonate of soda is a deep
orange-yellow color, and when diluted possesses a very strong green fluorescence. The

page_text: washing and drying, a brown resinous product exhibiting a green reflection is
obtained which dissolves in alkalies with yellow color and green fluorescence, is
insoluble in water and very soluble in alcohol. To this product the name of
saccharo-fluorescein has been given. It may be obtained in a pure crystalline state
by the following treatment:-
PREPARATION OF ACETYLATED SACCHARO-FLUORESCEIN.
The brown resinous coloring matter is heated to boiling with three times its weight
of acetic anhydride in a vessel furnished with a reflux condenser. It is then allowed
to cool and poured into a sufficient quantity of alcohol to decompose the excess of
acetic anhydride. The acetylated derative is precipitated in the form of a finely
crystalline powder slightly yellow in color, which is filtered and washed with alcohol.
When purified by dissolving in glacial acetic acid and re-precipitated with alcohol, it
melts at about 286° C. It is insoluble in water and in alcohol, soluble in warm glacial
acetic acid. Warmed in an aqueous solution of caustic soda it colors the solution yellow
with intense green fluorescence. By alcoholic solutions of alkalies it is completely
saponified.
The regeneration of pure saccharo-fluorescein from the acetylated derivative may be
effected by boiling with an alcoholic solution of caustic soda. When all is dissolved,
the solution is diluted with much water, filtered and acidified with acetic acid.
Saccharo-fluorescein crystallizes out in delicately coloured salmon flakes. The product
thus obtained is insoluble in water, but readily soluble in alcohol from which it may
be crystallized. It melts between 265° and 267° C. It dissolves in dilute alkalies
with a very pure yellow color and green fluorescence. Acids precipitate it from this
solution in orange-yellow flocks.
The condensation of saccharin with resorcinol can also be carried out in the presence
of condensation agents such as the chlorides of aluminium or zinc, or sulphuric acid,
but although the reaction takes place with greater rapidity the product is more
difficult to purify.
Halogen derivatives of saccharo-fluorescein may be prepared in the following
manner-Ten parts by weight of saccharo-fluorescein are dissolved in 50 parts by
weight of alcohol, and 11 parts by weight of bromine added gradually, the temperature
being maintained about 40° C. After all the bromine has been added, three parts by
weight of chlorate of scda dissolved in an equal weight of water is added, and the
whole boiled for half an hour in a vessel with reflux condenser. After addition of the
chlorate, the bromine compound begins to precipitate out in the form of small
reddish-brown crystals. The solution is cooled, the precipitate filtered off and washed
with alcohol. A crystalline powder is thus obtained insoluble in water and alcohol.
It dissolves in alkalies with a fine red color and has similar properties to eosine but a
more blueish nuance.
The iodo-saccharo-fluorescein prepared in a similar manner to the bromine
derivative is a reddish-yellow powder which dissolves in alkalies with a fine violet-red
color.
Having now particularly described and ascertained the nature of the said
invention, as communicated to me and in what manner the same is to be
performed, I declare that what I claim is :-
1. The manufacture of the new coloring matter, herein before called saccharo-
fluorescein, by heating together saccharin and resorcinol with or without the
employment of condensation agents, substantially as described.
2. The purification of the condensation product of saccharin and resorcinol through
the acetyl derivative, substantially as described.
3. The manufacture of halogen derivates of saccharo-fluorescein substantially as
described.

page_text: 4. As a new product, the coloring matter hereinbefore called saccharo-fluorescein,
which may be obtained for example by the condensation of saccharin with resorcinol
substantially as herein before described.
5. As a new product, the acetyl derivative of the condensation product hereinbefore
called saccharo-fluorescein, substantially as described.
6. As new products, the coloring matters being the halogen derivatives of the
the condensation product hereinbefore called saccharo-fluorescein, such as for example
may be obtained by treating saccharo-fluorescein so as to cause a combination with
halogen substantially as described.
Dated this 94th day of Inno 1067
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.