TYPES OF DYES FOR DIFFERENT DEPTH
• Dyes for deep shades
• Higher build up dyes most suitable here. Build up can be measured by plotting K/S Vs concentration. Higher build up dyes impart better reproducibility and better all round fastness. Of course these are cost effective.
• For black shades, target shade should be closer to self tone of dyes.
• Dyes for medium depth
• Bifunctional dyes are most preferable since BF dyes have medium substantivity and medium reactivity.
• Dyes for low depth
• Generally low to medium substantivity dyes are preferable. According to our market study RR series leading the position, having multi dimensional advantage.
DYES FOR DIFFERENT TONE
• Try to select dyes in such a way so that 2nd and 3rd component should be least possible.
• Dyes for critical tone
• Such dyes should be select who have similar dyeing behavior and less sensitive to different dyeing agencies.
• Other trichrome
• Specific trichromatic dyes should be select for specific tone. Such as, Lemon Yellow, T.Blue and Blue/Navy for Bright Green trichrome.
PROCESS CONTROL
• Trichromatic dyes should have similar behavior which ensure level and reproducibility dyeing.
• According to dyes behavior, suitable process has to be selected.
On line process checking is required to get level and RFT dyeing and that will guide you to go for blind dyeing
TRICHROMATIC DYES OF SIMILAR BEHAVIOR
• We check following properties process agencies of dyes :
• Substantivity (PE)
• Migration (MI)
• Exhaustion dyeing factor (EF)
• Secondary exhaustion (SE)
• Fixation dyeing factor (FDF)
• Final fixation (FF)
• Wash off (WO)
• Wash off of different stage
SUITABLE DYEING METHOD FOR RR TRICHROME
• All in method
• Isothermal method
• Points to be considered
• There is no reason for migration method since EF is very high. Migration method may effect in RFT.
• You can dose salt at start or later and at any rate. It does not matter since its exhaustion strike rate is very slow.
• FDF value indicates that it is a High reactive dyes so dosing of alkali also is the concern.
Wash off is higher which may cause problem of RFT. So it is always advisable to complete the dyeing cycle
• CONCLUSION OF RR TRICHROME.
• It can not be used where light fastness requirement is higher let say above 3-4.
• It should use for light to medium to depth may be up to 2% depth and since it has very good compatibility with each other, so it can be used in critical shades.
• Clearly it is salt sensitive dyes so care must be taken for maintaining salt concentration stable during different batches.
• At lower temperature blue pick up more and increase the temperature blue start come out and red started pick up. Yellow has a very strange behavior, it does not change much with increasing temperature.
• All in method is best for it but it can be used in isothermal method as well comfortably.
• It is an expensive dyes and poor build up properties make it more expensive.
• Any sort machinery should not have any problem for these dyes.
Since it can work at All-in Method and very good solubility, utility crisis is not a problem for it
• SUITABLE DYEING METHOD FOR SPX TRICHROME.
• Isothermal method
• Migration Method
• Points to be considered
• There is high risk for all in method since Yellow SPX and Navy SPX have low EF.
• Salt addition is better after addition of dyes.
• These are low to medium reactive dyes so alkali addition should follow the norms of dosing.
• Since Navy SPX does not have good migration, it is not recommended to dose dyes into the dye bath.
• Wash off is very close which will ensure RFT.
.CONCLUSION IN SPX TRICHROME
• Not recommended for high light fastness 4 in all depths and tones.
• All three dyes have outstanding wash fastness, it can be used as cross staining and Yarn dyeing.
• It is recommended for medium depth only.
• Dyeing temperature over 60oC may affect RFT.
• Here yellow increases its depth with temperature.
• Isothermal method may be comfortable but migration would be recommended when Navy SPX concentration is lower.
• It is comparatively a cheaper dyes and medium build up, ensures it cost affectivity in medium depth.
• May be used in all sort of machine and utility availability.
BRIGHT GREEN TRICHROME
• Though it may not be comfortable but among all dyes best trichrome would be
• Yellow 3GL
• Yellow RNL
• T.Blue G
• Blue BB new
• Try to avoid T.Blue all the time.
• Apart from that we shall have to keep in mind that molecular size of T.Blue is big and tendency to aggregate and agglomerate, so diffusion is difficult. So total dyeing procedure we shall have design on the basis of T.blue.
• Exhaustion temperature must be high may be more than 60oC with suitable dye bath conditioner and levelling agent.
• Salt at start is not at all permitted and it is always better to give the salt in portion wise. Addition of salt reduce the solubility of dyes in great extent which improve in alkaline pH, for this it is recommended to add little alkali at start. But in such cases other trichrome dyes must have to be low reactive.
Wash off high ensures low RFT apart from that none of the dyes shows exact same behavior with T.Blue which even make it more low
• ROYAL TRICHROMY.
• So according to data best trichrome would be:
• Red RB
• Blue RSPL
• Black B
• Blue RSPL is one of the very very few dyes which has anthoquinone based chromophore group so its behavior is also difficult to match with other.
• So isothermal and migration method seriously damage the stability of dyes more often it did not pick up rather remain in the bath.
• Exhaust temperature must be lower possible and temperature increase rate slower possible.
• The highest pick of the dyes at 55oC, so keep the temperature at that point about 30 mins to fix most Blue RSPL and then increase the temperature to 60oc. Please keep in mind that higher temperature would break the bond between dyes and fiber.
Always avoid Yellow dyes in this trichrome
• MAKE IT YOUR NORMS.
• In black tri-chrome, mixture black concentration should not be very low.
• Do not select complementary color in bi-color combination.
• Do not set specific dyeing method for a dye rather understand the dyes behavior and design the method according to that.
• Always try to work in trichrome for a certain depth and tone of shade.
• Set your check list of dyeing process and maintain it through out the year.
Technology is the best way to reduce your stress