Improvements in the Manufacture of Beta-methyl-eurhodine.
Year: 1893

page_text: Date of Application, 18th Sept., 1893
Complete Specification Left, 9th June, 1894-Accepted, 14th July, 1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Beta-methyl-eurhodine.
I, BENJAMIN WILLCOX of No. 47 Lincoln's Inn Fields, in the County of
London, Patent Agent 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, Germany) to be as follows :-
In the Specifications of Letters Patent Nos. 10138 and 10138A of 1892 granted
to James Yate Johnson on a communication from my present foreign correspondents
the production of a new class of alkylated induline dyes is described.
The process for the manufacture of beta-methyl-eurhodine described in the said
Specifications consists in heating together the azo-dye from diazo-sulphanilic acid
and mono-methyl-para-toluidine with alpha-naphthylamine hydrochlorate in the
presence of a suitable diluent. My foreign correspondents find that the same
product can be obtained by the interaction of beta-hydroxy-naphthoquinone-imide
and mono-methyl-ortho-toluylene-diamine under suitable conditions.
I will further illustrate the nature of the invention by an example but the
invention is not limited to this example.
Mix together about one hundred and seventy three parts of beta-hydroxy-
uaphoquinone-imide, about one hundred and thirty six parts of mono-methyl-ortho-
toluylene-diamine and about one thousand parts of glacial acetic acid, and heat the
mixture on the boiling water bath. In order to ascertain when the operation may
be interrupted work up small portions of the melt from time to time in the manner
hereinafter described for the entire mass and continue heating until successive tests
indicate that no further increase occurs in the quantity of beta-methyl-eurhodine
formed. Then extract the melt by boiling with very dilute hydrochloric acid,
repeating the extraction as long as colouring matter dissolves. Filter the solutions
obtained and add caustic soda solution to the entire extract. A brown precipitate
which contains the beta-methyl-eurhodine is obtained. Filter and wash with water.
Dissolve the residue after washing in dilute hydrochloric acid, filter the solution
and precipitate the beta-methyl-eurhodine hydrochlorate with common salt. Filter
and press. In order to more completely purify the product re-dissolve in water and
add just sufficient ammonia solution to give a distinct alkaline reaction, a precipitate
consisting chiefly of impurity is obtained, filter and precipitate the dye which remains
in solution, with common salt. Filter press and dry.
The beta-methyl-eurhodine hydrochlorate so obtained is a red crystalline powder
readily soluble in hot water giving a red solution.
Other diluents can be used instead of glacial acetic acid as described in the above
example such as ordinary acetic acid (containing about 30 per cent. C₂HO₂) or
alcohol acidified with the quantity of hydrochloric acid equivalent to the amount of
diamine used and the like.
Dated the 18th day of September 1893.

page_text: Improvements in the Manufacture of Beta-methyl-eurhodine.
I, BENJAMIN WILLCOX of 47 Lincoln's Inn Fields in the County of London
Patent Agent 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 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 Specification of Letters Patent Nos. 10,138 and 10,138A of 1892 granted
to James Yate Johnson on a communication from my foreign correspondents the
production of a new class of alkylated induline dyes is described. The present
invention consists in the manufacture of beta-methyl-eurhodine by a new or
improved process as bereinafter descibed.
The process for the manufacture of beta-methyl-eurhodine described in the
aforesaid Specifications consists in heating together the azo-dye from diazo-
sulphanilic acid and mono-methyl-para-toluidine with alpha-naphthylamine hydro-
chlorate in the presence of a suitable diluent. My foreign correspondents find that
the same product can be obtained by the interaction of beta-hydroxy-naphtho-
quinone-imide and mono-methyl-ortho-toluylene-diamine under suitable conditions.
I will further illustrate the nature of the invention and the manner in which it
can be carried into effect by an example but the invention is not limited to this
example.
Mix together about one hundred and seventy three parts by weight of beta-
hydroxy-naphthoquinone-imide, about one hundred and thirty-six parts by weight
of mono-methyl-ortho-toluylene-diamine and about one thousand parts by weight
of glacial acetic acid, and heat the mixture on the boiling water bath. In order to
ascertain when the operation may be interrupted work up small portions of the
melt from time to time in the manner hereinafter described for the entire mass and
continue heating until successive tests indicate that no further increase occurs in
the quantity of beta-methyl-eurhodine formed. Then extract the melt by boiling
with very dilute hydrochloric acid, repeating the extraction as long as colouring
matter dissolves. Filter the solutions obtained and allow the entire extract to cool,
then add caustic soda solution. A brown precipitate which contains the beta-
methyl-eurhodine is obtained. Filter and wash with water. Dissolve the residue
after washing in dilute hydrochloric acid filter the solution and precipitate the
beta-methyl-eurhodine hydrochlorate with common salt. Filter and press. In
order to more completely purify the product, redissolve in water and add just
sufficient ammonia solution to give a distinct alkaline reaction, a precipitate
consisting chiefly of impurity is obtained, filter and precipitate the dye which
remains in solution with common salt. Filter press and dry.
The beta-methyl-eurhodine hydrochlorate so obtained is a red crystalline powder
readily soluble in hot water giving a red solution.
Other diluents can be used instead of glacial acetic acid as described in the above
example such as ordinary acetic acid (containing about thirty per cent. C₂HO₂) or
alcohol acidified with the quantity of hydrochloric acid equivalent to the amount of
diamine used and the like.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is―
The manufacture of beta-methyl-eurhodine by the interaction of beta-hydroxy-

page_text: naphthoquinone-imide and nono-methyl-ortho-toluylene-diamine as herein mentioned
substantially as hereinbefore described.
Dated this 9th day of June 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, Agents.