Production of Dioxynaphtoic-mono-sulpho Acid and of its Salts.
Year: 1892

page_text: Date of Application, 5th Aug., 1892
Complete Specification Left, 3rd May, 1893-Accepted, 2nd June, 1893
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE SOCIETY OF CHEMICAL INDUSTRY IN
BASLE, of Basle, Switzerland.]
Production of Dioxynaphtoic-mono-sulpho Acid and of its Salts.
I, OLIVER IMRAY of 28 Southampton Buildings, Chancery Lane in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention to be as follows:-
The B-naphtol-carbon-acid of the melting point of 216° C. (German Patent
No. 50341 of 1st June 1889) can be easily converted into ẞ-oxynaphtoic-disulpho-
acid. On heating this latter with caustic alkalies it is transformed according to
the present invention into dioxynaplitoic-mono-sulpho acid in substituting for one
of the sulpho groups, the hydroxyl group.
The analysis of the acid baryum salt of this new dioxynaphtoic-mono-sulpho
acid indicates the following constitution :
-OH
-OH
C10 H.-COOH + 2 H₂O
-So, Ba
2
In order to produce 6-oxynaphtoic-disulpho acid : 10 parts by weight of
B-naphtol-carbon-acid of the melting point of 216° C. are introduced into 40 parts
by weight of fuming sulphuric acid of 24 p.c. anhydride, at a temperature of
from 100° to 120° C. After heating at a temperature of 100° to 160° C. during
2 to 3 hours, the reaction is completed. In introducing ẞ-naphtol-carbon-acid of
the melting point 216° C. into from 2 to 3 parts by weight of concentrated
sulphuric acid at a temperature of 60° C., two isomeric mono-sulpho acids of the
B-naphtol carbon acids are produced, which may be principally converted into the
same disulpho acid by addition of: 3 parts by weight of fuming sulphuric acid of
30 p.c. anhydride at a temperature of from 100 to 140° C.
If the sulphuration of naphtol-carbon acid (melting point 216°) is effected
with fuming sulphuric acid at a low temperature, an isomeric 13-oxy-naphtoic-
disulpho-acid is also formed in considerable quantity, and produces, by melting
with caustic alkalies, an isomeric dioxy-naphtoic-mono-sulpho acid, which is
different from the aforesaid new dioxy-naphtoic-mono-sulpho-acid and which is
separated from the latter by crystallization.
The product of the sulphuration is poured into water, saturated with lime and
its soda salt is then prepared, in the usual way, which separates by evaporation
as a crystalline mass.
To convert Boxy naphtoic disulphio acid into dioxy-naphtoicmono-sulpho acid
20 parts by weight of oxy-naphtoic-disulphonate of soda are heated with
40 parts by weight of caustic soda and 10 parts by weight of water during from
2 to 3 hours at from 210 to 220° C. and finally at from 230 to 260° C.
The reaction begins after a short time and is terminated as soon as the melt
solidifies. Its duration varies according to the quantity of caustic soda, or hydrate
of potash employed, and depends also upon the temperature of the reaction.
The above described process can be carried out in an open vessel or in a closed
vessel under pressure. In the latter case the quantity of caustic alkali may be

page_text: acid soda salt of the new dioxynaphtoic-mono sulpho acid separates in small light-
yellowish needles. It is obtained pure by filtering and crystallising from its
aqueous solution. In cold water it does not dissolve easily, but in warm water it
is readily soluble and separates in flat prisms. The neutral soda-salt crystallizes
from the aqueous solution in needles ranging in rosettes.
By addition of chloride of barium to the warm and saturated solution of the
acid soda salt, the acid barium salt that is not easily soluble in cold water,
crystallizes out in needles. In decomposing the barium salt by sulphuric acid,
dioxynaphtoic-mono-sulpho-acid is obtained."
It separates from the dilute muriatic acid in long faint-yellow needles which
dissolve easily in water.
The aqueous solutions of the alkaline salts of dioxynaphtoic-mono-sulpho acid
have a yellowish-green fluorescence; they produce dark indigo blue tints with
perchloride of iron and show an intense yellow orange coloration in a solution of
chloride of lime.
The dioxynaphtoic-mono-sulpho acid is used for the production of coloring
matters.
Dated this 5th day of August 1892.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Production of Dioxynaphtoic-mono-sulpho Acid and of its Salts.
I, OLIVER IMRAY of 28 Southampton Buildings, Chancery Lane in the
County of London, Chartered Patent Agent 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 :-
The B-naphthol-carbon-acid of the melting point of 216° C. (German Patent
No. 50341 of 1st June 1889 and Specification to British Letters Patent No. 9612
of 1889) can be easily converted into ß-oxynaphtöic-disulpho-acid. On heating this
latter with caustic alkalies it is transformed, according to the present invention,
into dioxynaphtöic-mono-sulpho acid, in substituting for one of the sulpho groups,
the hydroxyl group.
The analysis of the acid barium salt of this new dioxynaphtöic-mono-sulpho acid
indicates the following constitution :
-OH
.OH
C10 H
-COOH + 2 H₂O
-SO, Ba
2
In order to produce B-oxynaphtöic-disulpho acid: 10 parts by weight of
B-naphthol-carbon-acid of the melting point of 216° C. are introduced into 40 parts
by weight of fuming sulphuric acid of 24 per cent. anhydride at a temperature of
from 100° to 120° C. After heating at a temperature of 100° to 160° C. during
2 to 3 hours, the reaction is completed. In introducing ẞ-naphthol-carbon-acid of
the melting point 216° C. into from 2 to 3 parts by weight of concentrated
sulphuric acid at a temperature of 60° C., first, two isomeric oxynaphtöic-mono-
sulpho-acids are produced, which may be principally converted into the same
disulpho acid by addition of 3 parts by weight of fuming sulphuric acid of
per cent anhydride at a temperature of from 100° to 140° C.
30
The product of the sulphuration is poured into water, saturated with lime, and
its soda salt, then prepared in the usual way, separates by evaporation as a crystalline
mass.
To convert 3-oxynaphtöic-disulpho acid into dioxynaphtöic-mono-sulpho acid,

page_text: 20 parts by weight of ẞ-oxynaphtöic-disulphonate of soda are heated with 40 parts
by weight of caustic soda and 10 parts by weight of water during from 2 to 3 hours
at from 210° to 220° C. and finally at from 230° to 260° C.
The reaction begins after a short time and is terminated as soon as the melt
solidifies.
Its duration varies according to the quantity of caustic soda or hydrate of potash
employed, and depends also upon the temperature of the reaction.
The above described process can be carried out in an open vessel or in a closed
vessel under pressure.
In the latter case the quantity of caustic alkali may be
reduced without injury for the result.
The melt is introduced into warm dilute muriatic acid or sulphuric acid. The
acid soda salt of the new dioxynaphtöic-mono-sulpho acid separates in small light-
yellowish needles. It is obtained pure by filtering and crystallising from its
aqueous solution.
In cold water it does not dissolve easily, but in warm water it is
readily soluble and separates in flat prisms. The neutral soda-salt crystallizes from
the aqueous solution in needles ranging in rosettes.
By addition of chloride of barium to the warm and saturated solution of the
acid soda salt, the acid barium salt that is not easily soluble in cold water,
crystallizes out in needles. In decomposing the barium salt by sulphuric acid,
dioxynaphtöic-mono-sulpho acid is obtained.
It separates from the dilute muriatic acid in long faint-yellow needles which
dissolve easily in water.
The aqueous solutions of the alkaline salts of dioxynaphtöic-mono-sulpho acid
have a yellowish-green fluorescence; they produce dark indigo blue tints with
perchloride of iron and show an intense yellow orange coloration in a solution of
chloride of lime.
The dioxynaphtoic-mono-sulpho acid is used for the production of coloring
matters.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. The production of a new dioxynaphtöic-mono-sulpho acid and of its salts, by
heating with caustic alkalies the B-oxynaphtoic disulpho acid, which is obtained
by sulphonation of 3-naphthol-carbon acid of the melting point of 216°C.
substantially as described.
2. The new dioxynaphtöic-mono-sulpho acid and its salts resulting from the
process set forth in the preceding claim.
Deted this 2nd M. 1902
ABEL & IMRAY,
Agents for the Applicant.