Improvements in the Production of Blue Colouring Matters.
Year: 1890

page_text: Date of Application, 28th Oct., 1890
Complete Specification Left, 28th July, 1891-Accepted, 5th Sept. 1891
PROVISIONAL SPECIFICATION.
Improvements in the Production of Blue Colouring Matters.
I, DAN DAWSON, of Hoffman Street, Milnsbridge, near Huddersfield, Yorkshire,
Chemist, do hereby declare the nature of this invention to be as follows:
-
This invention has for its object the production of blue colouring matters by the
condensation of a salt of dimethylaniline with diphenylamine, benzildiphenylamine,
methyldiphenylamine, or ethyldiphenylamine, the latter four bodies being used
separately or conjointly with the salt of dimethylaniline. If hydrochlorate of
dimethylaniline be treated with bromine or chlorine in the presence of excess of
bydrochloric acid so as to partially brominate or chlorinate it, and then mixed with
diphenylamine and heated to drive off the excess of acid and kept during a
protracted period at a temperature of about 100° C., there will be produced by the
condensation of dimethylaniline with diphenylamine a blue colouring matter similar
in properties to triphenyl rosaniline blue. I have also investigated the effect of
other dehydrogenating agents on a mixture of dimethylaniline salts, and diphenyl-
amine and some of its substitution compounds, which has resulted in the elaboration
of the following processes.
In one process I take one equivalent of neutral hydrochlorate or other suitable
salt of dimethylaniline of commerce and two equivalents of diphenylamine, or, in
proportions by weight, 200 parts of dimethylaniline neutralized with hydrochloric
acid or other suitable acid, and 560 parts of diphenylamine, and I add to these
about 160 parts of phenol, or ordinary carbolic, to render the diphenylamine more
fluid, this mixture being heated in a water bath in a copper vessel until all the
diphenylamine has melted, then I stir in about 4500 parts of common salt and
160 parts of sulphate of copper, previously well ground together, the whole being
constantly stirred for several hours at a maintained temperature of about 95 to
100° C. The operation may last a longer or shorter time according to temperature,
mechanical stirring, or presence of more or less of water. The action will even
take place in the cold when the bodies mixed together are abandoned for weeks.
When the mass has become so thick that it can no longer be stirred, the operation
may be considered finished, the mass having assumed a rich copper coloured
appearance.
If a greater proportion of hydrochlorate of dimethylaniline salt or more
especially if some of the dimethylaniline be in the free state, a portion of violet
will be produced along with the blue. When benzildiphenylamine, methyl-
diphenylamine, or ethyldiphenylamine, are used in the place of diphenylamine,
either jointly or separately, a blue will be produced somewhat greener when dyed
on silk or wool.
Another process, carried out exactly like that previously described, consists in
substituting red prussiate of potash (ferricyanide of potassium) for sulphate of
copper, the quantity used being about five times that of the sulphate of copper,
used in the first process.
As the action, however, is slower, the mixture must be
maintained at a temperature of about 100° C. for about two days.
In another process I conduct bromine or chlorine into a concentrated solution of
hydrochlorate of dimethylaniline, using about one equivalent of bromine or chlorine
to about one equivalent of hydrochlorate of dimethylaniline. I then mix the
product with about two equivalents of diphenylamine and heat the mixture for a
protracted period or until there is no more colour being produced.
The colours produced by the preceding processes can be purified in the same
manner as diphenylamine blue, which is a well known process,-after having
extracted the salts of sodium and copper or other soluble matters by steeping in

page_text: When
cold water and afterwards repeatedly washing in acidulated hot water.
purified the colours are suitable for various purposes and in dyeing or calico
printing they are used in the same manner as those colours known as "spirit blues,"
made from rosaniline; or they may be sulphonated according to ordinary methods
and made into salts of the sulphonated compounds soluble in water; in this state
they are more adapted for animal fibres than vegetable fibres.
Dated this 27th day of October 1890.
TASKER & CROSSLEY,
Huddersfield, Agents.
COMPLETE SPECIFICATION.
Improvements in the Production of Blue Colouring Matters.
I, DAN DAWSON, of Hoffman Street, Milnsbridge, near Huddersfield, Yorkshire,
Chemist, 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 :-
This invention has for its object the production of blue colouring matters by the
condensation of a salt of dimethylaniline with diphenylamine, benzildiphenylamine,
methyldiphenylamine, or ethyldiphenylamine, the latter four bodies being used
separately or conjointly with the salt of dimethylaniline. If hydrochlorate of
dimethylaniline be treated with bromine or chlorine in the presence of excess of
hydrochloric acid so as to partially brominate or chlorinate it, and then mixed with
diphenylamine and heated to drive off the excess of acid and kept during a
protracted period at a temperature of about 100° C., there will be produced by the
condensation of dimethylaniline with diphenylamine a blue colouring matter similar
in properties to triphenyl rosaniline blue. I have also investigated the effect of
other dehydrogenating agents on a mixture of dimethylaniline salts, and diphenyl-
amine and some of its substitution compounds, which has resulted in the elaboration
of the following processes.
In one process I take one equivalent of neutral hydrochlorate or other suitable
salt of dimethylaniline of commerce, and two equivalents of diphenylamine, or in
proportions by weight, 200 parts of dimethylaniline neutralized with hydrochloric
acid or other suitable acid, and 560 parts of diphenylamine, and I add to these
about 160 parts of phenol, or ordinary carbolic, to render the diphenylamine more
fluid, this mixture being heated in a water bath in a copper vessel until all the
diphenylamine has melted, then I stir in about 4500 parts of common salt and 160
parts of sulphate of copper, previously well ground together, the whole being
constantly stirred for several hours, at a maintained temperature of about 95 to
100° C. The operation may last a longer or shorter time according to temperature,
mechanical stirring, or presence of more or less of water. The action will even
take place in the cold when the bodies mixed together are abandoned for wecks.
When the mass has become so thick that it can no longer be stirred, the operation
may be considered finished, the mass having assumed a rich copper coloured
appearance.
If a greater proportion of hydrochlorate of dimethylaniline salt or, more
especially if some of the dimethylaniline be in the free state, a portion of violet
will be produced along with the blue. When benzildiphenylamine, methyl-
diphenylamine, or ethyldiphenylamine, are used in the place of diphenylamine
either jointly or separately, a blue will be produced somewhat greener when dyed
on silk or wool.
Another process, carried out exactly like that previously described, consists in
substituting red prussiate of potash (ferricyanide of potassium) for sulphate of
copper, the quantity used being about five times that of the sulphate, of, copper
used in the first process. As the action, however, is slower, the inixture: must be
maintained at a temperature of about 100° C. for about two days.

page_text: In another process I conduct bromine or chlorine into a concentrated solution of
hydrochlorate of dimethylaniline, using about one equivalent of bromine or chlorine
to about one equivalent of hydrochlorate of dimethylaniline. I then mix the
product with about two equivalents of diphenylamine and heat the mixture for a
protracted period or until there is no more colour being produced.
The colours produced by the preceding processes can be purified in the same
manner as diphenylamine blue, which is a well known process, after having
extracted the salts of sodium and copper or other soluble matters by steeping in
cold water and afterwards repeatedly washing in acidulated hot water.
When
purified the colours are suitable for various purposes, and in dyeing or calico
printing they are used in the same manner as those colours known as "spirit blue,"
made from rosaniline; or they may be sulphonated according to ordinary methods
and made into salts of the sulphonated compounds, soluble in water; in this state
they are more adapted for animal fibres than vegetable fibres.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is
The production of blue colouring matters by the condensation of hydrochlorate
of dimethylaniline or other suitable salt of dimethylaniline with diphenylamine,
benzildiphenylamine, methyldiphenylamine, or ethyldiphenylamine, these latter
bodies being used either separately or jointly in the manner substantially as herein
described.
1
L1
1001
TASKER & CROSSLEY,
Huddersfield and Halifax, Agents.