Producing Fast Dyeings upon the Fibre by Means of Direct Dyeing Coloring-matters.
Year: 1897

page_text: Producing Fast Dyeings upon the Fibre by Means of Direct Dyeing
Coloring-matters.
I, SYDNEY PITT, of Sutton, in the County of Surrey, Gentleman, do hereby declare
the nature of this invention (which has been communicated to me from abroad by
Leopold Cassella & Co. of Frankfort-on-Main in the Empire of Germany) to be as
follows:-
According to this invention those direct dyeing cotton dyestuffs which contain
free amido-groups, are combined with diazo bodies upon the fibre forming new
combinations.
The dyeings thus developed with suitable diazo bodies, become absolutely fast to
milling. Generally a considerable increase of the intensity is connected with this
developing process. The process appears to be an inversion of the well known
method of diazotising amidized direct dyeing coloring-matters upon the fibre.
In the latter process for instance, the Diamine Black is transformed into its diazo
compound and is afterwards combined with so-called developers, such as Beta-
Naphtol, forming polyazo bodies of the type.

page_text: the amido-group.
In some cases the formation of primary disazo dyestuffs takes place simultaneously
with the formation of the diazoamido body, but in all cases it becomes evident that
the taking up of the diazo compound into the nucleus is only of secondary
importance. For if the corresponding primary disazo-compounds which are sub-
stituted in the nucleus, are previously prepared, it is found that they are neither
fast to milling nor insoluble, and they can only be fixed upon the fibre with diazo
bodies, if they still contain a free amido-group.
A very important group of such direct dyeing dyestuffs are those which derive
from m. phenylenediamine and analogous bodies.
If for instance dyeings produced with the dyestuffs known under the denominations
of Cotton Brown, or Benzo Brown, are treated with diazo bodies, they become
perfectly fixed, simultaneously gaining considerably in intensity; the complicated
polyazo dyestuffs such as for instance Diamine Jet Black, and Oxy-Diamine Black
which are also derivatives of m. phenylenediamine behave in a similar manner.
Tests have demonstrated that amongst the diazo bodies those which react
energetically, such as diazonitrobenzoles, diazoazo-benzole, the diazo-compound of
dehydrothiotoluidine and the like are most suitable.
Diazosulphonic or Diazo carbonic acids are of course not well adapted for the
purposes of the present process. Generally speaking the simple monodiazo bodies
yield better results than tetrazo bodies.
The process consists in dyeing the coloring matters in alkaline or saline baths in
the usual manner, and in immediately afterwards entering the goods into the bath
containing the diazo body. The latter may be either alkaline or acidulated with
acetic or mineral acids. The capability of most of the diazo bodies to react easily in
mineral acid solutions under the conditions of the present process, ie. in presence of
the fibre, is very striking and of great technical value. For it is well known that the
diazo bodies are very stable in acid solutions, whilst for instance, diazo solutions
saturated with acetate of soda remain fit for use only at low temperatures and for a
relatively short time. When the reaction is terminated which generally takes place
very quickly, the goods are wrung off, washed out, and if the diazotising bath has
been acid, are preferably slightly soaped.
The process can also be applied for the production of various print effects.
The following table contains some of the principal shades which may be produced
in the manner described.

page_text: Diamine Black R reddish black
violet black
black
"
"
"
"
B black
BH blue black
blackish blue
black
blue black
black
Diamine Blue 3B blueish green
Diamine Blue
Black E
blueish green
reddish black
black
blue black
blackish green greenish blue
black
blackish blue
black
blackish blue
Oxamine Violet
blackish violet
violet brown.
brownish violet
blackish violet
Diamine Brown
dark brown
dark brown
dark brown
brown
M
Diamine Brown
Diamine Brown
B
Diamine Cutch
violet brown'
violet brown
dark brown
""
"
brown
dark brown
brown
"
"
violet black
brownish violet brownish: violet
brownish violet
Diazo Blue
Diamine Jet
violet brown
brown
violet brown
blackish brown
blackish brown blackish brown
brown
blackish brown
Black S S
Diamine Jet
Black R B
Diamine Jet
Black Cr
Diamine Jet
dark brown
dark brown
وو
"
"
وو.
Black 0 0
".
"
99.
dark brown
Columbia Black R blackish brown
blackish brown blackish brown dark brown
وو
وو
99.
"
"
blackish brown
blackish brown
blackish brown
"
دو
BB brownish black
Direct Blue blackish brown
black(brownish)
blackish brown
black(brownish)
blackish brown
black
blackish brown
Black
Diazo Brilliant dark brown
brown
dark brown
brown
Black
jet black
black
black
black(brownish) black.
greenish black
black
Benzo Chrome blue black
Black Sooo
Black
Oxy Diamine
Oxy Diamine
Black N
Diaminogene
brownish black brownish black brownish black brownish black
black
black(brownish)
Cotton Brown N dark brown
brown
jet black
brown
black
brown
Benzo Brown
"
Toluylene Brown
"
G
ور
وو
"
yellowish brown
39
yellowish brown dark brown
dark brown
Toluylene
chestnut brown brown
Orange
Primuline
yellow
yellowish brown brown
greenish yellow reddish yellow golden yellow

page_text: to acids, they do not rub off and resist very well most of the reagents used in the
dyeing and printing industries.
Producing Fast Dyeings upon the Fibre by Means of Direct Dyeing
Coloring-matters.
I, SYDNEY PITT, of Sutton, in the County of Surrey, Gentleman, do hereby declare
the nature of this invention (which has been communicated to me from abroad by
Leopold Cassella & Co., of Frankfort-on-Main, in the Empire of Germany), and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
According to this invention those direct dyeing cotton dyestuffs which contain free
amido-groups, are combined with diazo bodies upon the fibre forming new
combinations.
The dyeings thus developed with suitable diazo bodies, become absolutely fast to
milling. Generally a considerable increase of the intensity is connected with this
developing process. The process appears to be an inversion of the well known method
of diazotising amidized direct dyeing coloring matters upon the fibre.
In the latter process for instance, the Diamine Black is transformed into its diazo
compound and is afterwards combined with so-called developers, such as Beta-Naphtol,
forming polyazo bodies of the type.

page_text: free amido-group.
In some cases the formation of primary disazo dyestuffs takes place simultaneously
with the formation of the diazoamido body, but in all cases it becomes evident that
the taking up of the diazo compound into the nucleus is only of secondary importance.
For if the corresponding primary disazo-compounds which are substituted in the
nucleus, are previously prepared, it is found that they are neither fast to milling nor
insoluble, and they can only be fixed upon the fibre with diazo bodies, if they still
contain a free amido-group.
A very important group of such direct dyeing dyestuffs are those which derive from
m. phenylenediamine and analogous bodies.
If for instance dyeings produced with the dyestuffs known under the denominations
of Cotton Brown, or Benzo Brown, are treated with diazo bodies, they become perfectly
fixed, simultaneously gaining considerably in intensity, the complicated polyazo
dyestuffs such as for instance Diamine Jet Black, and Oxy-Diamine Black which are
also derivatives of m. phenylenediamine behave in a similar manner.
Tests have demonstrated that amongst the diazo bodies those which react ener-
getically, such as diazonitrobenzoles, diazoazo-benzole, the diazo-compound of
dehydrothiotoluidine and the like are most suitable.
Diazosulphonic or Diazo carbonic acids are of course not well adapted for the
purposes of the present process. Generally speaking the simple monodiazo bodies
yield better results than tetrazo bodies.
The process consists in dyeing the coloring matters in alkaline or saline baths in
the usual manner, and in immediately afterwards entering the goods into the bath
containing the diazo body. The latter may be either alkaline or acidulated with
acetic or mineral acids. The capability of most of the diazo bodies to react easily in
mineral acid solutions under the conditions of the present process, i.e. in presence of
the fibre, is very striking and of great technical value. For it is well known that
the diazo bodies are very stable in acid solutions, whilst for instance, diazo solutions
saturated with acetate of soda remain fit for use only at low temperatures and for a
relatively short time. When the reaction is terminated which generally takes place
very quickly, the goods are wrung off, washed out, and if the diazotising bath has
been acid, are preferably slightly soaped.
The process can also be applied for the production of various print effects.
The following table contains some of the principal shades which may be produced
in the manner described.

page_text: Diamine Black R reddish black
violet black
black
وو
وو
"
"
B black
BH blue black
blackish blue
black
blue black
black
reddish black
black
blue black
Diamine Blue3 B blueish green
blueish green
blackish green
Diamine Blueblack
blackish blue
black
greenish blue
blackish blue
Black E
Oxamine Violet
blackish violet
violet brown
brownish violet
blackish violet
Diamine Brown dark brown
dark brown
dark brown
brown
M
Diamine Brown
violet brown
violet brown
dark brown
"
"
Diamine Brown
brown
dark brown
brown
"
"
B
Diamine Cutch
Diazo Blue
Diamine Jet
violet black
violet brown
blackish brown
brownish violet | brownish violet
brownish violet
brown
violet brown
brown
blackish brown blackish brown
blackish brown
Black S S
Diamine Jet
Black RB
Diamine Jet
Black Cr
dark brown
dark brown
17
"
"
"
"
"
""
"
"
"
"
"
Diamine Jet
dark brown
Black 00
Columbia BlackR blackish brown
">
"
Direct Blue
BB brownish black
blackish brown
blackish brown blackish brown dark brown
blackish brown blackish brown blackish brown
black (brownish) black (brownish) black
blackish brown blackish brown blackish brown
Black
Diazo Brilliant
dark brown
brown
Black
Benzo Chrome
blue black
jet black
dark brown
brown
'black
black
Black
Oxy Diamine
brownish black brownish black brownish black brownish black
Black Sooo
Oxy Diamine
black (brownish) black
Black N
Diaminogene
Cotton Brown N dark brown
greenish black black
brown
Benzo Brown
"
"
"
Toluylene Brown
"
"
G
Toluylene
chestnut brown brown
Orange
Primuline
yellow
yellowish brown dark brown
yellowish brown brown
greenish yellow reddish yellow golden yellow
black
black (brownish)
jet black
brown
black
brown
yellowish brown
"
dark brown

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
Developing dyeings produced by means of those direct dyeing cotton dyestuffs
which contain free primary amido-groups by treating the goods in a bath containing
diazocompounds substantially as described.