The Manufacture of Colouring-matters and of Intermediate Products related to the Rhodamine Series.
Year: 1893

page_text: Date of Application, 20th Dec., 1893
Complete Specification Left, 14th Sept., 1894-Accepted, 20th Oct., 1894
PROVISIONAL SPECIFICATION.
The Manufacture of Colouring-matters and of Intermediate Products
related to the Rhodamine Series.
I, JAMES YATE JOHNSON, of 47 Lincoln's Inn Fields, in the County of
Middlesex, 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-ón-Rhine, in the Empire of Germany,) to be as follows:-
If the rhodamine-bases derived from di-basic acids (phthalic acid and succinic
acid) be treated with ammonia or with derivatives thereof products are obtained
which can by suitable treatment be converted into valuable colouring matters.
Thus if tetra-ethyl-rhodamine of the phthalic series be treated with ammonia a
body containing a larger proportion of nitrogen is obtained. The chemical reaction
which takes place is probably the replacement of an oxygen atom by the imido
group (NH) and this intermediate product may therefore be called tetra-ethyl-
rhodamine-imide.
This body is not itself a useful colouring-matter though giving an intensely
coloured solution in glacial acetic acid but on treatment with suitable reagents for
splitting off water it yields a new rhodamine dye which resembles the known basic
rhodamines in its properties but yields bluer shades on dyeing.
If the said rhodamine be treated with aniline, or other primary aromatic amine,
instead of with ammonia, then bodies which appear to be the analogous phenyl-
imides (tolyl-imides and the like) are obtained. These bodies are also not
colouring-matters themselves though yielding coloured solutions in glacial acetic
acid, but by sulphonation they can be converted into valuable acid dyes which give
as bright shades on animal fibre on dyeing in the acid bath as do the rhodamines
themselves, and they possess the further valuable characteristic of dyeing darker
shades than can be obtained with the basic rhodamines.
The rhodamines suited for use for the purposes of the invention are those of the
phthalic acid and succinic acid series whether alkylated or not. They can be
condensed as aforesaid with ammonia and with primary aromatic amines; also
derivatives of such amines can be used.
The following examples will serve to further illustrate the nature of the invention,
but they are merely descriptions of its application to isolated cases and in all cases
the details of the process can be varied without departing from the nature of the
MI
EXAMPLE 1.
Dissolve about one part of tetra-ethyl-phthalic-rhodamine (rhodamine B extra)
in about five parts of alcohol and saturate the solution in the cold with ammonia
gas. Heat.the solution obtained in an autoclave to about one hundred and eighty
degrees centigrade for about ten hours and then allow the solution to cool. The
main portion of the product of the reaction crystallizes out in thick crystals.
Collect these crystals and wash with cold alcohol. Recrystallize if desired from
dilute alcohol, when colourless crystals which melt at about 229° C. are
obtained.
The rhodamine-imide so obtained gives a yellow solution in concentrated sulphuric
acid. In glacial acetic acid it dissolves giving an intensely red solution resembling

page_text: This salt is a red powder readily soluble in water giving a bluish-red solution with a
yellowish-red fluorescence. Dilute solutions lose their colour on addition of an
alkali, such as caustic soda, soda or ammonia. The free sulpho-acid is readily
soluble in hot water, and is also soluble without difficulty in the cold.
This new dye yields beautiful red and fluorescent shades on wool, the dark shades
being especially brilliant. The dye is characterized by a high degree of fastness
against the action of light.
The analogues of the "rhodamine-phenyl-imide" obtainable as herein before set
forth can also be sulphonated to yield valuable acid dyes. In all cases various
conditions of sulphonation can be observed and different sulpho-acids or mixtures of
sulpho-acids are obtained accordingly. Generally speaking the higher sulphonated
bodies are more pronounced dyes possessing greater solubility.
Dated this 20th day of December 1893.
J. H. JOHNSON & Co.,
Agents.
COMPLETE SPECIFICATION.
The Manufacture of Colouring Matters and of Intermediate Products
related to the Rhodamine Series.
1, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this invention (which has been com-
municated to me from abroad by The Badische Anilin and 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 :—
If the rhodamine bases derived from di-basic acids (phthalic acid and succinic
acid) be treated with ammonia or with derivatives thereof products are obtained
which can by suitable treatment be converted into valuable colouring matters.
Thus if tetra-ethyl-rhodamine of the phthalic series be treated with ammonia a
body containing a larger proportion of nitrogen is obtained. The chemical reaction
which takes place is probably the replacement of an oxygen atom by the amido-
group (NH) and this intermediate product may therefore be called tetra-ethyl-
rhodamine imide.
This body is not itself a useful colouring matter though giving an intensely
coloured solution in glacial acetic acid but on treatment with suitable reagents for
splitting off water it yields a new rhodamine dye which resembles the known basic
rhodamines in its properties but yields bluer shades on dyeing.
If the tetra-ethyl-rhodamine of the phthalic series be treated with aniline, or
other primary aromatic amine, instead of with ammonia, then bodies which appear
to be the analogous phenyl-imides (tolyl-imides and the like) are obtained. No
claim is made for the production of these bodies which are not colouring matters
themselves though yielding coloured solutions in glacial acetic acid, but by
sulphonation they can be converted into valuable acid dyes which give as bright
shades on animal fibre, on dyeing in the acid bath, as do the rhodamines themselves,
and they possess the further valuable characteristic of dyeing darker shades than
can be obtained with the basic rhodamines,
The rhodamines suited for use for the purposes of this invention are those of
the phthalic acid and succinic acid series whether alkylated or not. They can be
condensed as aforesaid with ammonia and with primary aromatic amines, also
derivatives of such amines can be used.
The following examples will serve to further illustrate the nature of the invention,
but they are merely descriptions of its application to isolated cases and in all cases
the details of the process can be varied without departing from the nature of the
invention. The parts are by weight.

page_text: dilute soda solution. Then pour into water filter off the separated sulpho-acid and
convert it into sodium salt.
This salt dissolves with difficulty in cold water but it is more soluble in hot
water.
EXAMPLE 5.
Add whilst stirring thoroughly one part of the rhodamine-phenyl-imide
(obtainable as described in Example 3) to about four parts of fuming sulphuric
acid containing about twenty three per cent. free auhydride (SO). Heat the mixture
on the water bath for about an hour and a half or until the resulting sulpho-acid
gives a sodium salt which is readily soluble even in cold water. Allow the mixture
to cool and pour the melt onto ice. The sulpho acid formed separates out in part
and a further quantity can be precipitated with common salt. Collect and convert
into sodium salt.
This salt is a red powder readily soluble in water giving a bluish-red solution
with a yellowish red fluorescence. Dilute solutions lose their colour on addition
of an alkali such as caustic soda, soda, or ammonia. The free sulpho acid is
readily soluble in hot water and is also soluble without difficulty in the cold.
This new dye yields beautiful red and fluorescent shades on wool, the dark
shades being especially brilliant. The dye is characterized by a high degree of
fastness against the action of light.
The analogues of the rhodamine-phenyl-imide obtainable as herein before set
forth can also be sulphonated to yield valuable acid dyes. In all cases various
conditions of sulphonation can be observed, and different sulpho acids or mixtures
of sulpho acids are obtained accordingly.
Generally speaking the higher sulphonated bodies are more pronounced dyes
possessing greater solubility.
Having now particularly described and ascertained the nature of this said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The manufacture of colouring matters related to the rhodamine series by first
treating the rhodamines hereinbefore defined with ammonia and then splitting off
water from the product so obtained substantially as hereinbefore described.
2. The manufacture of intermediate products (the rhodamine-imides herein
defined) by treating the rhodamines mentioned with ammonia substantially as
herein before described.
3. The conversion of the rhodamine-imides into colouring-matters related to the
rhodamine series by treating them with phosphorus oxychloride.
4. The manufacture of colouring-matters related to the rhodamine series by first
treating the rhodamines herein before defined with the aromatic amines herein
mentioned and then converting the products so obtained into sulpho acids.
5. The conversion of the rhodamine-phenyl-imides,-tolyl imides and the like,
into valuable_colouring matters by treating with sulphuric acid substantially as
hereinbefore described.
6. The manufacture of intermediate products in the manner described in
Example 1, and of colouring matters in the manners hereinbefore described in
Examples 2, 4 and 5. .
7. As new articles of manufacture the new intermediate products and new
colouring matters such as can be obtained substantially in the manners claimed in
the foregoing claiming clauses.
Dated the 14th day of September 1904.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, W.C., Agents.