For cotton in India reactive dye maximum demand is there due
to its brilliancy, reproducibility and wide range of shade possibility. Before
dyeing in reactive dye fabric (ready for dyeing fabric) should be free from
residual peroxide, alkali, size etc
Ready for dyeing cotton fabric in exhaust reactive dyeing required:
1) Fabric absorbency
should be less than 3 second by water drop check.
2) Fabric should be
free from residual peroxide or alkali
3) Fabric Ph should
be neutral .PH=6.5-7
4) Fabric centre
side variation checking by water and Ph indicator liquid solution. It should be
For lab to bulk correlation following point has to be
considered for ready for dyeing fabric (RFD):
1) Fabric Gsm (Gram
secure meter) should be same for lab and bulk. For cabinet dyeing machine
running lot pretreatment hank should be taken.
absorbency should be less than 3 second.
3) Fabric PH should
4) Proper dye
selection. Maximum try to take trichormy colour for shade matching.
5) M; L ratio
setting in machine and bulk.
For lab: a) for cabinet dyeing and winch machine:-1; 20
b) For soft flow m/c=1; 10
c) For Garment Dyeing m/c=1; 15
For Bulk dyeing (select those machine where following
parameter is available).
a) Water level indicator
should be available for exact maintaining of material liquor ratio.
b) Steam auto
controller should be available for exact maintaining of dyeing temperature for
evenness of shade.
Note: - for jigger dyeing take dyeing exert view for correlation maintaining
because jigger dyeing material; liquor ratio will be 1; 1 to 1:2.
6) Take same salt
and soda ash for reactive exhaust dyeing. Quantity of salt and soda ash should
for above mentioned machine.
Note: In Jigger dyeing lab salt and soda ash will be entirely different due
to its low material; liquor ratio. In practical quantity of salt and soda ash
will be entirely different as compared to lab recipe. Take expert view for
7) Lab recipe
should be taken water bath as a heating medium for exact correlation
maintaining because glycerin bath will not be correct for exhaust correlation
8) Soaping and
neutralizing is always a variable factor for correlation maintaining in
bulk.But for lab take soaping (for dark shade take 2 soaping for example-black
,dk maroon,dk turquoise blue shade, dk navy etc)at 90 degree celcius for 20
minute then hot wash(80 degree celcius ,holding time 10 minute) and dry.
In lab dyeing soaping mentioned bottom side:-
a) for light shade :( no soaping,) only hot wash.
b) For medium shade: only one soapinghot washescold wash.
c) For dark shade: two soapinghot washescold wash.
9) Soft Water
for dyeing should be taken for both Lab to bulk dyeing correlation maintaining.
If water hardness is more use suitable sequestering agent available in market
for bring down below 20 ppm. Water Ph should also check it should be neutral or
slight acidic no problem.
In lab dyeing no
need for taking leveling agent /lubricating agent for exhaust dyeing .(But for
bulk dyeing leveling agent /lubricating agent is must for soft flow dyeing
machine to get entirely evenness in fabric. In cabinet dyeing machine huge
quantity of water is used hence it is safer to used leveling /lubricating agent
because water movement is also less and material also stationary.)