The Manufacture and Production of New Dyes of the Rhodamine Series.
Year: 1894

page_text: Date of Application, 25th May, 1894
Complete Specification Left, 11th Feb., 1895-Accepted, 16th Mar., 1895
PROVISIONAL SPECIFICATION.
The Manufacture and Production of New Dyes of the Rhodamine
Series.
1, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of
London, Gentleman do hereby declare the nature of this invention (which has
been communicated to me from abroad by The Badische Anilin and Soda Fabrik,
of Ludwigshafen-on-Rhine, in the Empire of Germany) to be as follows:-
In the Specifications of the Letters Patent Nos. 7298 and 9633 of 1892 granted
to me on communications from my foreign correspondents the manufacture of esters
of tetra-alkylated and dialkylated rhodamines respectively is described. The said
esters are obtained by combining the corresponding rhodamines with a further
proportion of an alcohol in a suitable manner.
The present invention consists in the manufacture of dyes of analogous chemical
nature by combining rhodamine compounds with phenolic bodies instead of with
the alcoholic bodies used in the processes of the aforesaid Specifications.
The rhodamines which can be used are those derived from di-basic acids such
as phthalic and succinic acid. These can be combined with mono- or poly-hydric
phenolic bodies such as phenol, the naphthols, resorcinol, pyrogallol and the like.
To effect the combination an energetic condensing agent is preferably used such
for instance as phosphorus oxychloride. Further a diluent such as toluene, xylene
and the like can be used or if preferred an excess of the phenolic body can be taken
so that this excess acts as a diluent.
The new dyes are of a bluer shade of red than the rhodamines from which they
are obtained and than the corresponding alcoholic esters. The pyrogallol compound
not only fixes itself on a tannin mordant but yields lakes with the metallic mordants;
of these, for instance the tin and alum lakes are particularly remarkable.
The following examples will serve to further illustrate the nature of the
invention but they are merely typical instances and they can be considerably
varied without departing from the nature of the invention. The parts are by
weight.
EXAMPLE 1.
Mix together about four parts of the hydrochloric acid salt of tetraethyl
rhodamine (rhodamine B extra), or the corresponding quantity of the free base,
with one part of phenol, heat the mixture in an oil-bath to about one hundred and
ten to one hundred and twenty degrees Centigrade. Then, whilst thoroughly
stirring, add gradually about two parts of phosphorus oxychloride, and continue
heating till all, or nearly all, the rhodamine is converted into the new dye. This
can be ascertained by treating a test-portion of the melt after dilution with water
with sodium tartrate, or acetate, and extracting the solution with benzene, any
unchanged rhodamine will thus be converted into base, and dissolved by the
benzene. When the reaction is complete dissolve the entire product in hot water,
filter, add a little hydrochloric acid, allow to cool and filter to collect the dye. Or
to extract any rhodamine present the treatment with sodium tartrate and benzene
as described in the test may be applied to the solution of the melt.
When sufficiently pure the new dye crystallizes in fine hair-like needles with a
coppery lustre.
Its aqueous solution is violet-red in colour with an orange-red

page_text: fluorescence. It dyes wool and silk bluish-red shades and on cotton, mordanted
with tannin, the colour is reddish-violet. The affinity for the fibre is so good that
the baths become nearly exhausted.
A very similar dye, is obtained, by using resorcinol instead of phenol in the
above example, in this case it is advisable to use a larger excess of the phenolic
body...
Analogous dyes are similarly obtained from succinic acid rhodamines.
EXAMPLE 2.
Mix together about two parts diethyl-rhodamine, (salt or base) and one part
pyrogallol, and heat the mixture in an oil-bath to about one hundred and ten, to
one hundred and twenty; degrees Centigrade.-. Then, whilst stirring, add gradually
about one part of phosphorus oxychloride. The thick melt at first becomes more
liquid and hydrochloric acid, is evolved. As the reaction proceeds the mass
becomes thicker again and finally solidifies. Allow to cool, reduce to powder, and
extract with water, or very dilute. hydrochloric acid, to get rid of the excess of
pyrogallol, and any unchanged, diethyl rhodamine.
The,new dye is but slightly soluble in water and therefore is preferably prepared,
and used, in the form of paste. It dyes cotton, mordanted, with tin, or alum,
giving bluish-red shades. Chrome mordanted wool takes a somewhat less bluish
colour.
The corresponding dye from tetra-ethyl-rhodamine. gives, with the above
mordants, in each case, shades more inclined to blue or violet.
Dated this 25th day of May 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.
The Manufacture and Production of New Dyes of the Rhodamine
Series.nl
JAMES YATE JOHNSON of 47 Lincoln's Inn Fields, in the County, of
London Gentleman, do hereby declare the nature of this invention (which has
been communicated to me from abroad by The Badische Anilin & Soda Fabrik of
Ludwigshafen-on-Rhine in the Empire of Germany) and in what manner the same
is to be performed to be particularly described and ascertained in and by-the
following statement :-
In the Specifications of the Letters Patent Nos. 7298 and 9633 of 1892 granted
to me on communications from my foreign correspondents, the manufacture of
esters, of tetra-alkylated and dialkylated rhodamines respectively is described.
The said esters are obtained by combining the corresponding rhodamines with a
further proportion of an alcohol in a suitable manner.
The present invention consists in the manufacture of dyes of analogous chemical
nature by combining rhodamine compounds with phenolic bodies instead of with
the alcoholic bodies used in the processes of the aforesaid Specifications.
The rhodamines which can be used are those derived from di-basic acids such as
phthalic and succinic acid. These can be combined with. mono- or poly-hydric
phenolic bodies such as phenol, the naphthols, resorcinol, pyrogallol and the like..
To effect the combination an energetic condensing agent is preferably used such
for instance as phosphorus oxychloride. Further a diluent such as toluene, xylene
and the like can be used or if preferred an excess of the phenolic body selected can
be taken so that this excess acts as a diluent.
The new dyes are of a shade of red bluer than that of the rhodamines from which

page_text: they are obtained and than that of the corresponding alcoholic esters. The
pyrogallol compound not only fixes itself on a tannin mordant but yields lakes with
the metallic mordants; of these, for instance, the tin and alum lakes are particularly
remarkable.
The following examples will serve to further illustrate the nature of the
invention and the manner in which it can best be carried into practical effect but.
they are merely typical instances and they can be considerably varied without
departing from the nature of the invention. The parts are by weight.
EXAMPLE 1.
Mix together about four parts of the hydrochloric acid salt of tetraethyl
rhodamine (rhodamine B extra) or the corresponding quantity of the free base,
with one part of phenol, heat the mixture in an oil bath to about one hundred and
ten to one hundred and twenty degrees Centigrade. Then, whilst thoroughly
stirring, add gradually about two parts of phosphorus oxychloride, and continue
heating till all, or nearly all, the rhodamine is converted into the new dye. This
can be ascertained by treating a test portion of the melt, after dilution with water,
with sodium tartrate, or acetate, and extracting the solution with benzene. Any
unchanged rhodamine will thus be converted into base, and dissolved by the
benzene. When the reaction is complete dissolve the entire product in hot water,
filter, add a little hydrochloric acid, allow to cool and filter to collect the dye.
Or to extract any rhodamine present, the treatment with sodium tartrate and
benzene as described in the test may be applied to the solution of the melt.
When sufficiently pure, the new dye crystallizes in fine hair-like needles with a
coppery lustre. Its aqueous solution is violet-red in colour with an orange-red
fluorescence. It dyes wool and silk bluish-red shades, and on cotton, mordanted
with tannin, the colour which it dyes is reddish-violet. The affinity for the fibre is
so good that the baths become nearly exhausted.
A very similar dye is obtained by using resorcinol instead of phenol in the
above example, in this case it is advisable to use a larger excess of the phenolic
body.
Mix together about two parts diethyl rhodamine, (salt or base), and one part
pyrogallol, and beat the mixture in an oil-bath to about one hundred and ten to
one hundred and twenty degrees Centigrade. Then, whilst stirring, add gradually
about one part of phosphorus oxychloride. The thick melt at first becomes more
liquid and hydrochloric acid is evolved. As the reaction proceeds the mass becomes
thicker again and finally solidifies. Allow to cool, reduce to powder and extract
with water, or very dilute hydrochloric acid, to get rid of the excess of pyrogallol.
and any unchanged diethyl rhodamine.
The new dye is but slightly soluble in water and therefore is preferably
prepared and used in the form of paste. It dyes cotton mordanted with tin, or
alum, giving bluish-red shades. It dyes chrome mordanted wool a somewhat less
bluish colour.
The corresponding dye from tetra-ethyl-rhodamine gives, with the above
mordants, in each case, shades more inclined to blue or violet.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The manufacture of new dyes of the rhodamine series by combining
rhodamines derived from di-basic acids with phenolic bodies substantially as
herein before described.

page_text: 2. The manufacture of new dyes of the rhodamine series in the manners.
hereinbefore described in the examples.
3. As new articles of manufacture the new rhodamine phenolic esters such as can
be obtained substantially in the manner hereinbefore described and claimed.
Dated this 11th day of February 1895.
JOHNSONS & WILLCOX,
Agents.