IMPROVEMENTS IN THE MANUFACTURE OF DYES OR COLORING MATTERS
Year: 1881

page_text: .
LETTERS PATENT to Ferdinand August Zimmermann, of 21, Mincing Lane,
in the City of London, Merchant, for an Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF DYES OR COLORING MATTERS." A communication
from abroad by Julius Frederick Holtz, of Berlin, in the Empire of
Germany.
PROVISIONAL
SPECIFICATION left by the said Ferdinand August
Zimmermann at the Office of the Commissioners of Patents on the 23rd
April 1881.
FERDINAND AUGUST ZIMMERMANN, of 21, Mincing Lane, in the City of London,
Merchant. "IMPROVEMENTS, IN THE MANUFACTURE or DYES OR COLORING
MATTERS." A communication from abroad by Julius Frederick Holtz, of, Berlin,
in the Empire of Germany.
This Invention relates to the manufacture of certain colouring matters by treating
in the manner hereinafter described certain derivatives of salicylic acid or materials
forming such acids or equivalent materials.
In carrying out this Invention I first prepare crude sulphosalicylic acid. The
weights of materials employed I will describe as molecular weights, in order that
the processes may be more readily followed by chemists in all countries, no matter
which of the many systems of weights or measures may ordinarily be used in the
respective countries.
'
I mix one molecular. weight of salicylic acid (C, H. O.) with three molecular
weights of (strong) sulphuric acid (H. SO₁) at any temperature, but I prefer
about 120° centigrade. The resulting impure crude sulpho salicylic acid is really a
mixture of isomeric or very closely allied sulpho salicylic acids, one in large pro-
portion and one in small proportion, though only one results almost exclusively
if the temperature be 170° C. In any case the product is purified by adding
carbonate of barium to saturation, rejecting the insoluble sulphate of bariuma by
tiltration or otherwise, and evaporating the resulting solution of sulpho salicylic

page_text: acid to dryness, preferably in a vacuum. The resulting substance is what I usually
employ under the name of sulpho salicylic acid in the processes now to be
described,
Froin sulpho salicylic acid I prepare as follows nitro compounds, nitrobromo
compounds, and other bodies, nearly all of which are good colorific substances.
Any nitrating process inay be used except that in which a mixture of concentrated
nitric acid with concentrated sulphuric acid is employed.
To form the mononitrosulpho salicylic acid I prefer to mix one molecular weight
of sulpho salicylic acid with about two molecular weights of nitric acid of specific
gravity 135 or roughly in ordinary weights about equal parts of each. This
mixture I subject to a temperature of 40° to 50° C for 30 to 36 hours, stirring
occasionally. I next isolate the nitro-acid thus formed by adding chloride of
barium, washing the resulting acid, nitrosulphosalicylate of barium, with cold
water, in which it is only slightly soluble, decomposing this barium salt by sulphuric
acid filtering from the separated sulphate of barium, and carefully evaporating.
The product is a bright yellow fluid of the consistency of thin syrup crystallizable
if necessary,
The nitrosulphosalicylic acid may also be prepared from nitrates other than
nitric acid (H NO.). Thus three molecular weights of nitrate of barium (Ba 2 NO,)
and two of sulphosalicylic acid may be used, with enough sulphuric acid to yield
nitric acid with the nitrate of barium. 118 parts of the sulphosalicylic acid
dissolved in 90 to 100 parts of water are mixed with 27 parts of concentrated
sulphuric acid. Into this mixture is gradually stirred a solution of 71 parts of
nitrate of barium in 450 parts of water of a temperature of 45° to 50° C., the
whole is kept warm for 30 hours. Filtered from the sulphate of barium the
resulting nitrosulphosalicylic acid is purified as before by adding chloride of
barium and decomposing the washed nitrosulphosalicylate of barium by sulphuric
acid.
'
. If nitrosulphosalicylates other than nitrosulphosalicylic acid itself are desired
the product of the reaction of nitric acid with sulphosalicylic acid is neutralized
by carbonate of barium, and the filtered solution set aside to crystallize. The
crystals by recrystallization yield pure nitrosulphosalicylate of barium in bright
yellow scales. From the latter other nitrosulphosalicylates are obtainable by
double decomposition with carbonates. The nitrosulphosalicylates of the alkali
inetals, including ammonium, and of the alkaline earth metals, are yellow crystalline
substances, which for silk and wool are direct dyes needing no fixing process.
Those best suited are the calcium and barium salts. The calcium salt crystallizes
in needles and dissolves easily in water but slowly in alcohol. The barium salt is
insoluble in alcohol.
If in forming nitrosulphosalicylic acid a higher temperature than that stated be
employed, or nitric acid of much greater specific gravity than that indicated be
used, or two great an excess of nitric acid, then nitrosalicylic acid, free sulphuric
acid, and other products will appear. The same remarks apply to mixtures of
nitric and sulphuric acids, more highly nitrated bodies, and even pieric acid being
formed.
The colouring power of nitrosalicylates also is marked, but is increased both in
body and intensity by the introduction of bromine into the molecules of the nitro-
salicylates forming bromonitrosalicylates.
Bromine may also be introduced into nitrosulphosalicylates forming bromonitro-
sulphosalicylates, but these two colour silk and wool of a less intense yellow than
the colour communicated by the. bromonitrosalicylates.
The bromonitrosulpho-
salicylic acids are made by the action of bromine on nitrosulphosalicylic acids; one

page_text: molecular weight of either of the latter acids is attacked by one of bromine in
dilute solution. The temperature must be kept very low, otherwise sulphuric
acid will be regenerated and bromonitrosalicylic acids be produced.
Bromonitrosalicylic acids are obtained at once on dropping 160 parts of bromine
from a siphon-pipette into a continuously stirred solution of 263 parts of nitro-
sulphosalicylic acids in 500 or 600 parts of water. Or the bromine may be dissolved
in once or twice its weight of bisulphide of carbon. In the latter case an upright
and slightly warmed condenser should be used, so that vapours may condense
and react and flow back to the digesting vessel. The following equation represents
the reaction :-
The product of the reaction is a inore or less crystalline mass of two broino-
nitrosalicylic acids varying in proportion according to the proportion to each other
of the two isometric nitrosulphorsalicylic acids, from which the bromo acids have
been prepared. The proportion of the less stable variety of the two nitrosulpho
acids decreasing as we rise in making those acids from 120° C. to 170° C., the
formation of one only or of a mixture of the bromo acids is within the control of
the operator, he using nitrosulpho acids inade at the lower or the higher temperature
for the manufacture of the particular bromo acid or mixture of bromo acids he
may desire to produce. The reaction then having ended, the resulting more or less
crystalline mass is separated by filtration, and still more obtained by evaporation
the filtrate on a water bath to about one third of its bulk, and setting aside for
more crystals to form. The two bromonitrosalycylic acids may be separated by
fractional crystallization from alcohol, the less soluble being obtained in broad
golden, yellow, lamellæ, or sometimes in a mass of comparatively thick needle
shaped particles, the other afterwards crystallizing out in a less intensely coloured
dull yellow mass. In some cases the two bromno acids may be heated with carbonate
of calcium and water. The bromonitrosalicylate of calcium in the larger proportion
is also less soluble than the other, and separates first from the solution in thick
deep red needles, the mother liquor yielding the other acid in golden yellow scales.
Both salts are freely soluble in alcohol. The separate or the mixed bromonitro-
salicylates, either of potassium, sodium, ammonium, &c., but especially the barium
and calcium salts, have great tinctorial power. The rod line salt dyes silks and
wool of a golden yellow; the yellow lime salt gives a somewhat lighter shade.
The acid separated from the red lime salt by hydrochloric acid and recrystallized
is a monobromonitrosalicylic acid; it is slightly soluble in cold alcohol, freely in
hot, and scarcely soluble in water.
By action of more bromine than one inolecular weight on one of nitrosulpho-
salicylic acid, the operation being kept up for some time, a more highly brominated
body is obtained, the salts of which dye silk and wool yellow.
Bromosulphosalicylic acid is obtained by adding one molecular weight (that is
two atomic weights, or 160 parts) of bromine froin a capillary siphon to a con-
tinuously stirred aqueous solution of one molecular weight (218 parts) of .the
originally described sulphosalicylic acid. The reaction may be thus expressed :—
SO₂H
Br
as in reality two sulposalicylic acids are employed, two bromosulphosalicylic acids
result; but the latter neutralized by barium carbonate yield barium salts which
readily crystallize, and from the separated salts the purified acids can be regenerated
by reaction with sulphuric acid. Upon very careful evaporation of the aqueous
0 solutions they separate as a yellow crystalline mass.

page_text: Bromonitrosalicylic acid may be obtained not only by digesting broinine with
nitrosulphosalicylic acid, as already described, but by digesting the bromosulpho-
salicylic acid just mentioned with about an equal weight of nitric acid of sp. gr. 1.2.
It is accompanied by a second nitro compound, but the two can be separated by
fractional crystallization of the calcium salts. The second acid crystalizes in light
yellow needles, and its calcium salts in honey yellow needles. Not only the
regenerated bromosulphosalicylic acid but the crude acid may be used in this
process. Nitration proceeds best with a mixture of one part by weight of bromo-
'sulphosalicylic acid to 3 or 4 parts of water, and with a not too concentrated nitric
acid.
1.
I obtain a bromonitrosalicylic acid or nitrobromosalicylic acid by the action also
of dilute nitric acid on bromosalicylic acid. If the latter (obtained as already shown
by the reaction of bromine with salicylic acid) be attacked by strong nitric acid
nitrosalicylic acid is obtained and bromine liberated; and with highly concentrated
nitric even picric acid results. But I digest about ten parts by weight of finely
powdered bromosalicylic acid with about 30 parts of nitric acid of specific gravity
111, and when nitrous vapours cease to be evolved set the mixture aside to cool.
The crystalline product separated from mother liquor by filtration or otherwise is
purified either by recrystallization from alcohol or by conversion into a barium.
salt (by boiling with carbonate of barium), recrystallization of the latter, and
regeneration of the bromonitrosalicylic acid by action of hydrochloric acid, and on
the bromonitrosalicylic of barium. This bromonitrosalicylic acid occurs as light
yellow warty masses of crystals, slightly soluble in water, readily in alcohol, and
by reaction with carbonnates easily yields salts. The bromonitrosalicylates are
yellow and give that color to silk and wool.
I also obtain a bromonitrosalicylic acid by the action of the nitric acid of specific
gravity 13 upon a concentrated solution of a bromosalicylic acid in glacial acetic
acid..
I have already said that I may form bromonitrosalicylates by introducing
bromine into nitrosalicylates. Of this reaction of bromine with the three known
nitrosalicylic acids, that with the so called orthonitrosalicylic acid (melting when
hydrous at 125° C., and when anhydrous at about 145° C.) yields the bromo-
nitrosalicylic acid and other bromonitrosalicylates of greatest tinctorial power.
The nitrosalicylic acid may be that obtained as a bye product in nitrating salicylic
acid with nitric acid of specific gravity 14. From iso meric nitrosalicylic acids
formed at the same time it may be separated by the known process of fractional
crystallization from acetic acids. One hundred and sixty parts of bromine are
added very gradually to one hundred and eighty three parts of the anhydrous
nitrosalicylic acid with continual rubbing in a mortar or otherwise. Or a mixture
of the nitrosalicylic acid with water may be treated with a solution of the bromine
in bisulphide of carbon, evolved vapours being condensed and allowed to flow back
into the generating vessel by suitable arrangements of apparatus well known to
chemists, the resulting monobromonitrosalicylic acid may be readily purified by.
recrystallization from alcohol. It melts at about 115° C. The other bromonitro-
salicylates are readily prepared as usual, are yellow, and dye wool and silk lemon
yellow. The bromonitrosalicylate of calcium is perhaps most useful for this
purpose, being soluble either in water or in alcohol.
I introduce into sulphosalicylic acid and the other salicylic derivatives not only
halogens like broinine and inorganic groups like the nitro group, but organic groups
also, and so produce new colouring agents. Thus I act upon sulphosalicylic acid
with hydroxyl derivatives (phenols) like resorcin and pyrogallic acid, or with
hydroxylised carbon acids, such as trioxybenzoic acid (gallic acid). For instance,
I melt together at a temperature of 180° to 200° C. two molecular weights of
resorcin with one molecular weight of sulphosalicylic acid, and when water ceases
to separate dilute the product with weak solution of am monia, filter and neutralize
with a weak acid; brownish red flocks then separate, possessing strong. colouring
power. The alkaline combinations of this substance yield fluorescent solutions.

page_text: which with a fixing agent dye silk and wool brown red. The products similarly
obtained from gallic acid and from pyrogallic acid have somewhat similar
properties.
I also produce compounds by acting upon a sulphosalicylic acid with diazocom -
binations, diazoamido combinations, and amidoazo combinations, such for instance
as diazomidobenzol, netadiazoamidoxylol, diazoamidonaphthalin, nitrate of diazo-
xylol and amidoazonapthalin. For example, one hundred parts of diazoainido-
benzol are gently warmed with 120 parts of sulphosalicylic acid and 1000 parts of
water, and when solution, is complete resulting volatile oily matters driven off by
steam and the fluid concentrated crystalline aggregations of dark red needles are
thus obtained which are soluble in water, forming a brownish red dye. So 10 parts
of diazometaxylidin, 90 of sulphosalicylic acid, and 1000 of water when similarly
treated yield a residue which with glacial acetic acid gives a fluid from which
bright red needles are obtained; these act as a direct fuchsia red dye to silk.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Ferdinand August Zimmermann in the Great Seal Patent Office
on the 22nd October 1881.
FERDINAND AUGUST. ZIMMERMANN, of 21, Mincing Lane, in the City of London,
Merchant. "IMPROVEMENTS IN THE MANUFACTURE OF DYES OR COLORING
MATTERS." (A communication from abroad by Julius Frederick Holtz, of Berlin,
in the Empire of Germany.)
This Invention relates to the manufacture of, certain colouring matters by
treating in the manner hereinafter described certain derivatives of salicylic acid or
materials forming such acids or equivalent materials.
In carrying out this Invention I first prepare crude sulphosalicylic acid. The
weights of materials employed I will describe as molecular weights, in order that
the processes may be more readily followed by chemists in all countries, no matter
which of the many systems of weights or measures may ordinarily be used in the
respective countries.
mix one molecular weight of salicylic acid (C, H, O₂) with three molecular
weights of (strong) sulphuric acid (H, SO) at any temperature, but I prefer about
120° centigrade. The resulting impure crude sulpho salicylic acid is really a
mixture of isomeric or very closely allied sulpho salicylic acids, one in large pro-
portion and one in small proportion, though only one results almost exclusively
if the temperature be 170° C. In any case the product is purified by adding
carbonate of barium to saturation, rejecting the insoluble sulphate of barium by
filtration or otherwise, and evaporating the resulting solution of sulphosalicylic
acid to dryness, preferably in a vacuum. The resulting substance is what I usually
employ under the name of sulphosalicylic acid in the processes now to be
described.
Salicylic acid.
A sulphosalicylic acid.
From sulphosalicylic acid I prepare as follows nitro compounds, nitrobromo
compounds, and other bodies, nearly all of which are good colorific substances.
Any nitrating process may be used except that in which a mixture of concentrated
nitric acid with concentrated sulphuric acid is employed.
To forin the mono nitro sulphosalicylic acid I prefer to mix one molecular weight
of sulpho salicylic acid with about two molecular weights of nitric acid of specific
gravity 135, or roughly in ordinary weights about equal parts of each. This
mixture I subject to a temperature of 40° to 50° C. for 30 to 36 hours, stirring
occasionally. I next isolate the nitro acid thus formed by adding chloride of
barium, washing the resulting acid nitrosulphosalicylate of barium with cold
water, in which it is only slightly soluble, decomposing this barium salt by
sulphuric acid, filtering from the separated sulphate of barium, and carefully
evaporating. The product is a bright yellow fluid of the consistency of thin syrup,
crystallizable if necessary.
The nitro sulphosalicylic acid may also be prepared from nitrates other than
nitric acid (H NO,). Thus three molecular weights of nitrate of barium
(Ba 2 NO) and two of sulphosalicylic acid may be used, with enough sulphuric
acid to yield nitric acid with the nitrate of barium. 118 parts of the sulpho-
salicylic acid dissolved in 90 to 100 parts of water are mixed with 27 parts of
concentrated sulphuric acid. Into this mixture is gradually stirred a solution of

page_text: 71 parts of nitrate of barium in 450 parts of water of a temperature of 45° to 50° C.
The whole is kept warm for 30 hours. Filtered from the sulphate of barium the
resulting nitrosulphosalicylic acid is purified as before by adding chloride of barium,
and decomposing the washed nitrosulphosalicylate of barium by sulphuric acid.
If nitrosulphosalicylates other than nitrosulpbosalicylic acid itself are desired
the product of the reaction of nitric acid with sulphosalicylic acid is neutralized
by carbonate of barium and the filtered solution set aside to crystallize.
The
crystals by recrystallization yield pure nitrosulphosalicylate of barium in bright
yellow scales. From the latter other nitrosulphosalicylates are obtainable by
double decomposition with carbonates. The nitrosulphosalicylates of the alkali
metals, including ammoniun, and of the alkaline earth metals are yellow crystalline
substances which for silk and wool are direct dyes, needing no fixing process.
Those best suited are the calcium and barium salts. The calcium salt crystallizes
in needles and dissolves easily in water but slowly in alcohol. The barium salt is
insoluble in alcohol.
If in forming nitrosulphosalicylic acid a higher temperature than that stated be
employed, or nitric acid of much greater specific gravity than that indicated be
used, or too great an excess of nitric acid, then nitrosalicylic acid, 'free sulphuric
acid, and other products will appear. The same remarks apply to mixtures of nitric
and sulphuric acids, more highly nitrated bodies, and even picric acid being
formed.
The colouring power of nitrosalicylates also is marked, but is increased both in
body and intensity by the introduction of. bromine into the molecules of the
nitrosalicylates forming bromonitrosalicylates.
Bromine may also be introduced into nitrosulphosalicylates forming brounonitro-
sulphosalicylates, but these too colour silk and wool of a less intense yellow than
the colour communicated by the bromonitro salicylates. The bromonitro sulpho-
salicylic acids are made by the action of bromine on nitrosulphosalicylic acids; one
molecular weight of either of the latter acids is attacked by one of bromine in
dilute solution. The temperature must be kept very low, otherwise sulphuric acid
will be regenerated and bromonitrosalicylic acids be produced.
Bromonitrosalicylic acids are obtained at once on dropping 160 parts of bromine
from a siphon-pipette into a continuously stirred solution of 263 parts of nitro-
sulphosalicylic acids in 500 or 600 parts of water. Or the broinine may be
dissolved in once or twice its weight of bisulphide of carbon. In the latter case an
upright and slightly warmed condenser should be used, that vapours may
condense and re-act and flow back to the digesting vessel. The following equation
represents the re-action :-
so
SO, H
NO₂
NO₂
Br.
The product of the reaction is a more or less crystalline mass of two bromonitro-
salicylic acids varying in proportion according to the proportion to each other of
the two isomeric nitrosulphosalicylic acids from which the bromo acids have been
prepared. The proportion of the less stable variety of the two nitrosulpho acids
decreasing as we rise in making those acids from 120° C. to 170° C.; the formation
of one only or of a mixture of the bromo acids is within the control of the
operator, he using nitrosulpho acids made at the lower or the higher temperature
for the manufacture of the particular bromo acid or mixture of bromo acids he
may desire to produce. The reaction then having ended, the resulting more or
less crystalline mass is separated by filtration, and still more obtained by
evaporating the filtrate on a water bath to about one third of its bulk, and setting
aside for more crystals to form. The two bromonitrosalycylic acids may be
separated by fractional crystallization from alcohol, the less soluble being obtained
in broad golden, yellow, lamellæ, or sometimes in a mass of comparatively thick

page_text: needle-shaped particles, the other afterwards crystallizing out in a less intensely
coloured dull yellow mass. In some cases the two broino acids may be treated
with carbonate of calcium and water. The bromonitrosalicylate of calcium in the
larger proportion is also less soluble than the other, and separates first from the
solution in thick deep red needles, the mother liquor yielding the other acid in
golden yellow scales. Both salts are freely soluble in alcohol,
The separate or the mixed bromonitrosalicylates, either of potassium, sodium,
ammonium, &c., but especially the barium and calcium salts, have great tinctorial
power. The red lime salt dyes silks and wool of a golden yellow; the yellow lime
salt gives somewhat lighter shade. The acid separated from the red lime salt by
hydroshloric acid and re-crystallized is a monobromonitrosalicylic acid; it is slightly
soluble in cold alcohol, freely in hot, and scarcely soluble in water.
By action of inore bromine than one molecular weight on one of nitrosulpho-
salicylic acid, the operation being kept up for some time, a more highly brominated
body is obtained, the salts of which dye silk and wool yellow.
Bromosulphosalicylic acid is obtained by adding one molecular weight (that is,
two atomic weights, or 160 parts) of bromine from a capillary siphon to a
continuously stirred aqueous solution of molecular weight (218 parts) of the
originally described sulphosalicylic acid. The reaction may be thus expressed :-
SO, H.
Br
.
as in reality two sulphosalicylic acids are employed two bromosulphosalicylic acids
result; but the latter neutralized by barium carbonate yield barium salts which
readily crystalize, and from the separated salts the purified acids can be regenerated
by reaction with sulphuric acid. Upon very careful evaporation of their aqueous
solations they separate as a yellow crystalline mass.
Bromonit rosalicylic acid may be obtained not only by digesting bromine with
nitrosulphosalicylic acid, as already described, but by digesting the bromosulpho-
salicylic acid just mentioned with about an equal weight of nitric acid of sp. gr 1.2.
It is accompanied by a second nitro compound, but the two can be separated by
fractional crystallization of the calcium salts. The second acid crystallizes in light
yellow needles and its calcium salts in honey-yellow needles. Not only the
regenerated bromosulphosalicylic acid but the crude acid may be used in this
process. Nitration proceeds best with a mixture of one part by weight of bromo-
sulphosalicylic acid to 3 or 4 parts of water, and with a not too concentrated nitric
acid.
I obtain a bromonitrosalicylic acid or nitrobromosalicylic acid by the action also
of dilute nitric acid on bromosalicylic acid. If the latter (obtained as already known
hy the reaction of bromine with salicylic acid) be attacked by strong nitric acid
nitrosalicylic acid is obtained and bromine liberated, and with highly concentrated
nitric even picric acid results. But I digest about 10 parts by weight of finely
powdered bromosalicylic acid and with about 30 parts of nitric acid of specific
gravity 111, and when nitrous vapours ceased to be evolved set the mixture aside to
cool. The crystalline product separated from mother liquor by filtration or other-
wise is purified either by recrystallization from alcohol or by conversion into a
barium salt (by boiling with carbonate of barium), recrystallization of the latter
and regeneration of the bromonitrosalicylic acid by action of hydrochloric acid, and
on the bromonitrosalicylic of barium. This bromonitrosalicylic acid occurs as light
yellow warty masses of crystals, slightly soluble in water, readily in alc., and
by reaction with carbonnates easily yields salts. The bromonitrosalicylates are
yellow and give that color to silk and wool."
I also obtain a bromonitrosalicylic acid by the action of, nitric acid of specific
gravity 13 upon a concentrated solution of a bromosalicylic acid in glacial acetic

page_text: I have already said that I may form bromonitrosalicylates by introducing
bromine into nitrosalicylates. Of this reaction of bromine with the three known
nitro salicylic acids, that with the so called orthonitrosalicylic acid (melting when
hydrous at 125° C., and when anhydrous at about 145° C.) yields the bromonitro-
salicylic acid and other bromonitrosalicylates of greatest tinctorial power. The
nitrosalicylic acid may be that obtained as a by-product in nitrating salicylic acid
with. nitric acid of specific gravity 14. From isomeric nitrosalicylic acids formed
at the same time it may be separated by the known process of fractional crystal-
lization from acetic acid. One hundred and sixty parts of bromine are added very
gradually to one hundred and eighty three parts of the anhydrous nitrosalicylic
acid with continual rubbing in a mortar or otherwise. Or a mixture of the nitro-
salicylic acid with water may be treated with a solution of the bromine in bisulphide
of carbon, evolved vapours being condensed and allowed to flow back into the
generating vessel by suitable arrangements of apparatus well known to chemists;
the resulting monobromonitrosalicylic acid may be readily purified by recrystal-
lization from alcohol. It melts at about 115° C. The other bromonitrosalicylates
are readily prepared as usual, are yellow, and dye wool and silk lemon yellow.
The bromonitrosalicylate of calcium is perhaps most useful for this purpose, being
soluble either in water or in alcohol
I introduce into sulphosalicylic acid and the other salicylic derivatives not only
halogens like bromine and inorganic groups like the nitro group, but organic groups
also, and so produce new colouring agents. Thus I act upon sulphosalicylic acid
with hydroxyl derivatives (phenols) like resorcin and pyrogallic acid, or with
hydroxylised carbon acids, such as trioxybenzoic acid (gallic acid). For instance,
I melt together at a temperature of 180° to 200° C. two molecular weights of
resorcin with one molecular weight of sulphosalicylic acid, and when water ceases
to separate, dilute the product with weak solution of ammonia, filter, and neutralize
with a weak acid. Brownish red flocks then separate, possessing strong coloring
power. The alkaline combinations of this substance yield fluorescent solutions,
which with a fixing agent dye silk and wool brown red. The products similarly
obtained from gallic acid and from pyrogallic acid have somewhat similar
properties.
I also produce compounds by acting upon sulphosalicyclic acid with diazo-
combinations, diazoamido combinations, and amidoazo combinations, such for
instance as diazoamidobenzol, metadiazoamidoxylol, diazoamidonapthalin, nitrate
of diazoxylol, and amidoazonapthalin. For example, one hundred parts of
diazoamidobenzol are gently warmed with 120 parts of sulphosalicylic acid
and 1000 parts of water, and when solution is complete resulting volatile oily
matters driven off by steam and the fluid concentrated. Crystalline aggregations
of dark red needles are thus obtained which are soluble in water, forming a
brownish red dye. So 100 parts of diazometaxylidin, 90 of sulphosalicylic acid,
and 1000 of water when similarly treated yield a residue which with glacial acetic
acid gives a fluid from which bright red needles are obtained; these act as a
direct fuchsia red dye to silk.
Having now described the nature of the said Invention, and in what manner
the same is to be performed,
I declare that I claim,-
First. The processes for the preparation of nitrosulphosalicylic acids and
their salts by nitrating in various ways sulphosalicylic acid, more especially by
acting on sulphosalicylic acid by nitric acid of specific gravity 1.35, or by the
equivalent action of mixtures of nitrates with sulphuric acid as described.
Secondly. I claim the processes for the preparation of bromonitrosalicylic acids,
and of bromine substitution products of nitrosulphosalicylic acids by the action of
molecular quantities of bromine upon nitrosulphosalicylic acids, and the processes
for the preparation of the other bromonitrosalicylates, as set forth.
Thirdly. I claim the processes for the preparation of the monobromsulphosalicylic
acid and the corresponding metallic or other salts by the substitutional introduction

page_text: of molecular quantities of bromine into the sulpho acids formed by the action of
concentrated sulphuric acid upon salicylic acids as described.
Fourthly. I claim the processes for the preparation of monobromonitrosalicylic
acids and salts by treatment of monobromosulphosalicylic acids with dilute nitric
acid or equivalent nitration as set forth.
Fifthly. I claim the processes for the preparation of monobromonitrosalicylic
acids and salts by the nitration of monobromosalicylic acids in any manner, but
principally by the use of diluted nitric acid as described.
Sixthly. I claim the processes for the preparation of monobromonitrosalicylic
acids and salts from the nitrosalicylic acids, but more especially from the so-called
orthonitrosalicylic acid by the substitutional introduction of bromine into the acids,
as:set forth.
Seventhly. I claim the processes for the preparation of colouring matters by
treating sulphosalicylic acids with phenols, such as resorcin and pyrogallic acid, or
with phenolcarbonic acids, as gallic acid, as described.
Eighthly. I claim the processes for the preparation of colouring matters by
treating sulphosalicylic acids with diazoamido compounds as diazoamidobenzol or
metadiazoamidoxylol or diazoainidonapthalip, as set forth.
.
In witness whereof, I, the said Ferdinand August Zimmermann, have
hereunto set my hand and seal, this Twenty second day of October, in
the year of our Lord One thousand eight hundred and eighty one.
FERDINAND AUGUST ZIMMERMANN (L.S.)