• The term “disperse dye” have been applied to the organic
colouring substances which are free from ionizing groups, are
of low water solubility and are suitable for dyeing
• Disperse dyes are the only water insoluble dyes that dye
polyester and acetate fibers. Disperse dye molecules are the
smallest dye molecules among all dyes.
• Disperse dyes are used for dyeing man made cellulose ester
and synthetic fibres specially acetate and polyester fibres and
sometimes nylon and acrylic fibres.
• Carrier or dispersing agents are required for dyeing with
• Disperse dyes have fair to good light fastness with rating
MECHANISM OF DISPERSE DYE
Wander Wall’s Forces.
High affinity for Fibers.
Attraction between Fiber Surface and the Dye
Non-Soluble in Water.
Penetrate Because of Transition State of Synthetic Fibers.
Human effect dyeing method.
: Good .
: Good .
: Good .
Gas Fume Fade : Average .
They are Applied to Synthetic Fibers such as
Acetate, Triacetate, Polyester, Nylon and Acrylic.
Wide Range of Colors.
Bright and Lighter Shades.
Major Colors: Pale Yellow and Blue.
Cheap method for dyeing process .
Other agents used in
• It increases the solubility of the dye in water .
• It helps to increase the rate of the dye exhaustion .
• Leveling agents hold the rate of the dyeing and
helps to get uniform dyeing.
• These agents protect the dye from reduction in
high temperature bath .
High temperature dyeing process .
High Temperature Dyeing Process
• High temperature dyeing of polyester can be done in
Beam Dyeing machines , Jet dyeing machines
and Pressure Jiggers .
• This method dye applied under pressure at
temperature of about 130`c .
• Heating help to swell the highly compact
polyester polymer and make available
more space for the dye molecule to enter
in to the amorphous region of the fiber .
Dyeing Of Polyester Fabric With Disperse Dyes By
High Temperature Exhaust Method
Prepare The Dye Bath Using The Recipe Below
• Ammonium Sulphate
• Dispersing Agent
1:30 to 1:40
Dye The Sample Using The Following Dyeing Cycle
Dyeing With Disperse Dye
( High Temperature Exhaust Method )
• First the dye bath is made with the dye , dispersing agent and
the temperature is raised to 60`C .
• Next , Formic acid and Ammonium-Sulphate added till the pH is 5-6 .
• The dyeing should be continued and the temperature is raised to
130`C over period of 45 min.
• Then temperature reaches 130`C dyeing is done for 1 hour .
• Rinsed the sample with cold water .
• Removal the disperse dye on the surface of the fabric by
using Caustic Soda and Sodium Hydrosulphite and rinsed , Neutralize
• This process is suitable for mixed fabric of
Poly-Cotton or Poly-Wool .
• The thermo-sol dyeing process is consists of the
following stages .
The Padding Carried Out At 30 - 40`C With The
Acetic Acid ( pH 6 – 7 )
Neutral alginate thickener
• After padding the cloth with the dye and the other
Next stage is fixation of the disperse dye , the cloth is passed
through a hot air pin stenter for 60 second at 190 – 210 `C.
• After heat treatment the cloth washed .