A. Patil et al
299
OH
OH
OH
HO
HO
Cationic
Agent
OH
OH
OH
HO
O
Cotton
Cationic Cotton
Fig. 6 Cationization mechanism
adjusted according to the process requirement but the desired pH for cationization
treatment is set from neutral to slightly acidic because at this pH the protonation of
amine groups (–NH 2 ) of cationizing agent occurs and that increases the degree of
cationization. The cationizing agents can be applied by the following methods.
3.4.1 Exhaust Method
Exhaust method is also known as batch or discontinuous application method. In this
method, dye molecule or finishing agents migrate from solution on to the textile
material. The efficiency of the process depends upon the influencing factors like the
chemistry of the dye or finishing agent, liquor ratio, pH and temperature required for
the process [47, 48]. The process is preferred if the chemical agents have a strong
affinity to the substrate [28].
3.4.2 Padding Method
This method is used when chemical agents have a low affinity for substrates. This
process involves the application of chemicals through padding solution and then
squeezing with the help of pair of rollers as per desired pickup percent, followed
by drying and curing for fixation of chemicals on the substrates. The process is also
referred to as pad-dry-cure method [49].
3.4.3 Coating Method
In this process, coating material i.e. polymeric material is applied on one or both
sides of fabric forming a layer on the surface followed by drying and curing [50].
299
OH
OH
OH
HO
HO
Cationic
Agent
OH
OH
OH
HO
O
Cotton
Cationic Cotton
Fig. 6 Cationization mechanism
adjusted according to the process requirement but the desired pH for cationization
treatment is set from neutral to slightly acidic because at this pH the protonation of
amine groups (–NH 2 ) of cationizing agent occurs and that increases the degree of
cationization. The cationizing agents can be applied by the following methods.
3.4.1 Exhaust Method
Exhaust method is also known as batch or discontinuous application method. In this
method, dye molecule or finishing agents migrate from solution on to the textile
material. The efficiency of the process depends upon the influencing factors like the
chemistry of the dye or finishing agent, liquor ratio, pH and temperature required for
the process [47, 48]. The process is preferred if the chemical agents have a strong
affinity to the substrate [28].
3.4.2 Padding Method
This method is used when chemical agents have a low affinity for substrates. This
process involves the application of chemicals through padding solution and then
squeezing with the help of pair of rollers as per desired pickup percent, followed
by drying and curing for fixation of chemicals on the substrates. The process is also
referred to as pad-dry-cure method [49].
3.4.3 Coating Method
In this process, coating material i.e. polymeric material is applied on one or both
sides of fabric forming a layer on the surface followed by drying and curing [50].