The Manufacture of New Sulphonic Acids from Indigo Coloring Matters
Year: 1898

page_text: Date of Application, 16th Dec., 1898
Complete Specification Left, 9th Sept., 1899-Accepted, 11th Nov., 1899
PROVISIONAL SPECIFICATION.
The Manufacture of New Sulphonic Acids from Indigo Coloring
Matters,
A communication from LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE, ancienne-
ment 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:-
-
This invention relates to the manufacture of new sulphonic acids from indigo
coloring matters such as are obtained by the nitration of meta-toluylic aldehyde,
separation of the two mono-nitro products formed these products melting at 64°
and 44° C. respectively, condensation with acetone in alkaline solution and treat-
ment of the condensation products with alkali. These indigo coloring matters
apparently possess the chemical constitution of isomeric methyl-indigoes.
My correspondents have now discovered that the two indigo coloring matters
obtainable from meta-toluylic aldehyde as above referred, and hereinafter called
indigo 64° and indigo 44°, yield by appropriate treatment with sulphuric acid
mono- and di-sulpho derivatives analogous to the sulpho compounds manufactured
from natural indigo.
Indigo 64° may be sulphonated with greater facility than indigo 44° which
requires a more concentrated acid and a higher temperature. The mono- and di
sulphonic acids respectively may be prepared under the following conditions, but
it is well understood that the conditions of the reactions are capable of extensive
modification.
MONO-SULPHONATED INDIGOES.
5 parts indigo are triturated for some time with 50 parts 98 per cent. sul-
phuric acid, and the mixture allowed to stand for ten hours at a temperature of
about 20° C. It is then diluted with 500 parts of water and the unaltered indigo
filtered off. The excess of sulphuric acid in the filtrate is precipitated with chalk
or carbonate of barium, filtered off, and the solution neutralised with carbonate
of soda and again filtered. The filtrate is evaporated to dryness or may be pre-
cipitated with sea-salt when the sodium salt of the sulphonated indigo is obtained
in the form of a powder with bronze sheen.
The mono-sulphonated indigo 64° dyes wool and silk a very pure blue, whilst
the product from indigo 44° dyes a more greenish tint.
DI-SULPHONATED INDIGOES.
These products may be obtained in the same manner as the mono-sulphonated
by the employment of fuming sulphuric acid. For example, 5 parts of indigo
is mixed with 50 parts sulphuric acid containing 10 per cent, anhydride and the

page_text: mixture maintained for some hours at 20° to 30° C., until a sample dissolves
entirely in water. The separation is effected in the same manner as described
above for the mono-sulphonated products. The di-sulphonated indigoes, especially
that from indigo 44° C. dye a more greenish tint than the mono-sulphonated.
Dated this 16th day of December 1898.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.
The Manufacture of New Sulphonic Acids from Indigo Coloring
Matters.
A communication from LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE, ancienne-
ment 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, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to the manufacture of new sulphonic acids from indigo
coloring matters such as are obtained by the nitration of meta-toluylic aldehyde,
separation of the two mono-nitro products formed these products melting at 64°
and 44° C. respectively, condensation with acetone in alkaline solution and treat-
ment of the condensation products with alkali. These indigo coloring matters
apparently possess the chemical constitution of isomeric methyl-indigoes.
My correspondents have now discovered that the two indigo coloring matters"
obtainable from meta-toluylic aldehyde as above referred, and hereinafter called
indigo 64° and indigo 44°, yield by appropriate treatment with sulphuric acid
mono- and di-sulpho derivatives analogous to the sulpho compounds manufactured
from natural indigo.
Indigo 64° may be sulphonated with greater facility than indigo 44° which latter
requires a more concentrated acid and a higher temperature. The mono- and di-
sulphonic acids respectively may be prepared under the following conditions, but
it is well understood that the conditions of the reactions are capable of extensive
modification.
MONO-SULPHONATED INDIGOES.
5 parts indigo 64° are triturated for some time with 50 parts 98 per cent. sul-
phuric acid, and the mixture allowed to stand for ten hours at a temperature of
about 20° C. It is then diluted with 500 parts of water and the unaltered indigo
filtered off, The excess of sulphuric acid in the filtrate is precipitated with chalk
or carbonate of barium, filtered off, and the solution neutralised with carbonate
of soda and again filtered. The filtrate is evaporated to dryness or may be pre-
cipitated with sea-salt when the sodium salt of the sulphonated indigo is obtained
in the form of a powder with bronze sheen.
The mono-sulphonated indigo 64° dyes wool and silk a very pure blue, whilst
the product from indigo 44° dyes a more greenish tint.
DI-SULPHONATED INDIGOES.
These products may be obtained in the same manner as the mono-sulphonated
by the employment of fuming sulphuric acid. For example. 5 parts of indian 64°
!

page_text: is mixed with 50 parts sulphuric acid containing 10 per cent. anhydride and the
mixture maintained for some hours at 20° to 30° C., until a sample dissolves
entirely in water. The separation is effected in the same manner as described
above for the mono-sulphonated products. The di-sulphonated indigoes, especially
that from indigo 44° C. dye a more greenish tint than the monosulphonated.
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 per-
formed, I declare that what I claim is: —
The manufacture of mono- and di-sulphonic acids of the methyl indigoes called
herein respectively indigo 64° and indigo 44° substantially as described.
Dated this 9th day of September 1899.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.