FAQ

OLIGOMER formation in polyester dyeing, especially in microfiber is inevitable and exist as dark specks on fabrics and as cloud dust on cheese dyeing.
OLIGOMER inhibition is achieved in two steps.

Machine cleaning
Dyeing machine should be cleaned frequently, even in light shades.
NaOH, fl: 3–4 g/L
MEGACLEAR 12: 1 g/L
JETCLEAN OLG: 3–4 g/L
Temp: 135–140 °C
Time: 1 hr

JETCLEAN OLG is a catalyst for destruction of oligomer under high pH. Its foam is stable even at high temperature and enables the liquor to reach extreme corners of the dyeing machine.

Dyeing Process
UNIPES COMFORT is water-soluble resin which anchors on polyester fiber enhancing its hydrophility.
COMFORT suspends oligomers in water as small molecules and makes them water-soluble and drainable.
UNIPES COMFORT: 1 g/L

Please read Oligomer Prevention.

Due to its hydrophobic character, polyester fabrics and blends are sensitive to crease marks.
UNIPES COMFORT is a water-soluble resin which anchors on polyester fiber to make it hydrophilic and antistatic. Crease formation is totally inhibited.
Water is heated to 40–50°C with COMFORT, and the fabric is loaded. Before initial use, the dyeing machine should be cleaned.

Most pH regulating chemicals are acetic/formic acids or buffers. They are volatile and escape into the gas phase during dyeing, making the dye bath more alkaline.
Disperse dyes sensitive to alkali—such as Blue 79 and fluorescent/XHF dyes—are highly affected by pH changes.
In lab tubes, liquid-gas phase doesn’t exist due to continuous motion, ensuring stable pH.
Using Exoline 3H (a non-volatile buffer) keeps pH in bath stable as in lab conditions.

Due to the enlargement of surface area of microfiber polyester as compared to regular polyester, required dye amount is doubled or tripled. Extra amount of dye is also adsorbed by lycra fibers which impairs sublimation and washing fastness.

We advise two successive reducing treatment.

Acidic RC in the dye bath at 80 – 90 °C

 

MEGACLEAR 4 – 11 Liquid	3 – 4
Acetic Acid pH=4	x
Time, min.	20

 

PS/After the addition of MC 4/11,pH should be checked to 4.

Alkali post treatment in separate bath.

 

MEGACLEAR 12	1 – 2 g/L
NaoH, fe	4 – 7 g/L
Exolube NC	1
Temp., °C	95
Time, min.	20

 

Hot wash and neutralize.

Notes:

In acid treatment, pH after the addition of MEGACLEAR 4- 11 should  be pH=4

In alkaline clearing process pH, should end -up with

pH= 11,5 – 12

In finishing, silicone usage should be kept at minimum amount.

If final treatment temp is 180 – 220 °C it is advisable to rewash at 50-60 C and dry at 130 C.

In vinyl sulphone-based dyes such as Blue 19, Blue 21, and certain Navy Blue or Black shades, severe staining may occur on adjacent polyester stripes.

To prevent this issue, EKSOY recommends the use of PESCLEAN 2B.

---

Pre-treatment (Before Dyeing)

Wash the fabric with the following recipe:

• PESCLEAN 2B: 1%

• Temperature: 60 °C

• Time: 20 minutes

---

During Dyeing with Reactive Dyes

• Add PESCLEAN 2B: 1% directly to the dye bath.

In case of incorrect matching of the desired shade or uneven dyeing, partial or full decolorization may be required.

---

Partial Stripping – 10–30% Shade Reduction

Depending on the degree of decolorization, the following formulation is recommended:

• Soda Ash: 10–20 g/L

• EXOLUBE NC: 1.0 g/L

• EXOLINE 3025: 2–3 g/L

• Liquor Ratio: 1:10

• Temperature: 95 °C

• Time: 60 minutes

---

Full Stripping

For complete removal of shade, use the following recipe:

• MEGACLEAR 12: 2–4 g/L

• NaOH (solid): 5 g/L

• EXOLUBE NC: 1–2 g/L

• Temperature: 95 °C

• Time: 60 minutes

Note: When working with Turquoise HF-G, increase the amount of MEGACLEAR 12 and NaOH by 30%.

---

Important Note:

For effective usage of MEGACLEAR 12, the final pH of the stripping operation should be between pH 11.0–12.0.
If the pH is lower, add more alkali and continue the treatment for an additional 30 minutes at 95 °C.

For Kimsoline dyes, dye fixing is generally not required if the recommended dyeing procedures are followed and the fabric is thoroughly washed using EXOLINE MAGIC 3M or 4M.

---

If Fixing Is Needed

COLORFIX NF 2P can be safely used without causing any shade change.

• It is formaldehyde-free,

• Has a low cationic charge,

• Yet provides high fixation efficiency, even for scarlet and red shades.

Fixing Recipe:

• COLORFIX NF 2P: 0.5 – 1%

• pH: 5.5

• Temperature: 50 °C

• Time: 20 minutes

---

Note:
Cationic or nonionic softeners can also be added in the same bath without any issue.

If removal of COLORFIX NF 2P is required, apply the following acidic treatment:

Stripping Recipe:

• Acetic Acid (85%): 2 – 5 mL/L

• EXOLUBE NC: 2 – 3 mL/L

• Temperature: 80 °C

• Time: 20–30 minutes

In physics, sublimation refers to the phase change from solid directly to gas without passing through the liquid state.
In textile dyeing, this phenomenon is observed when disperse dyes in dyed polyester fibers migrate from the fiber core and volatilize into the atmosphere—especially at temperatures above 150 °C, during processes like heat setting, ironing, or post-curing. This leads to staining of adjacent fibers.

---

Factors Affecting Sublimation in Disperse Dyes

The sublimation fastness of disperse dyes is closely related to molecular size:

---

Other Factors Influencing Sublimation Fastness

• Dyeing strength (depth of shade)

• Efficiency of reduction clearing

• Heat setting temperature

• Use of finishing chemicals

Note: In very pale shades, even E Type dyes can show acceptable sublimation fastness.

---

Improving Sublimation Resistance

A strong reduction clearing process significantly reduces sublimation-related staining.

Recommended reduction clearing formula:

• MEGACLEAR 12: 2–4 g/L

• NaOH (solid): 5 g/L

• EXOLUBE NC: 1–2 g/L

• Temperature: 95 °C

• Time: 60 minutes

MEGACLEAR 12 is a highly effective, odor-free chemical designed for strong reduction clearing.

Effect of Liquor Ratio on Reactive Dyeing

Reactive dyes generally have low substantivity, meaning their uptake is highly influenced by the liquor ratio.

• A lower liquor ratio increases the dye fixation rate.

• Higher circulation rates and lower liquor ratios result in higher dyestuff yield, often producing darker shades.

This is the main reason for shade variation between lab and production machines, as lab machines typically operate at lower circulation speeds.

---

Key Notes on Salt and Alkali Dosing

• Dye catalogs usually provide salt/alkali dosing based on a 1:10 bath ratio.

• When applying dyeing at a lower liquor ratio (e.g., 1:6 or similar), the salt amount should be reduced by approximately 30% to prevent:

  • Excessively dark shades

  • Off-shades

  • Poor rubbing fastness

• Conversely, at lower liquor ratios, alkali dosing should be increased to achieve a target pH of 10.6–11.0.

• If the liquor ratio is higher than 1:10, the opposite adjustments should be applied:

  • Increase salt

  • Reduce alkali

---

These adjustments are critical to ensure consistent shade reproducibility across different dyeing machines and bath sizes.

Let me know if you’d like to compile all these dyeing guidelines into one professional document.

End-of-Dyeing Residues on Fabric

At the end of dyeing, three key substances remain on the fabric:

• Electrolyte (salt)

• Alkali

• Hydrolyzed dye

1. Electrolyte Removal

• Must be removed via cold water rinsing until the solution drops below 2° Baume.

• Hot water rinsing should be avoided here, as it may cause hue shifts in the dye.

• If salt is not sufficiently removed, the substantivity of hydrolyzed dye remains high, making wash-off more difficult.

---

2. Neutralization

• Perform effective salt rinsing and neutralization before soaping.

• Use volatile acids such as acetic acid or formic acid.

• Although hydrolyzed dye has greater substantivity at lower temperatures (especially in hard or salty water), cold rinsing is still preferred to minimize shade variation that may occur at high temperatures.

---

3. Soaping Process

• Use high-performance soaping agents such as:

  • EXOLINE MAGIC 3M

  • EXOLINE MAGIC 4M

• Use soft salt in the process.
  If hard salt is used or rinsing is insufficient, add:

  • ANTISIL MAY: 1.0%

    • A strong sequestering and dispersing agent

    • Highly effective at high pH and boiling temperatures

    • Prevents calcium crystal agglomeration — a point where many conventional sequestering agents fail

---

Soaping and Final Hot Wash Recommendations

• Use boiling temperature for soaping and hot washes
  → This helps decrease the substantivity of hydrolyzed dye to cotton.

---

Post-Dyeing Procedure (for Dark Shades)

1. Cold Rinse – 10 min

2. Neutralization & Soaping – 80 °C, 15 min

   • pH: 5.0–5.5 (with acetic acid)

   • EXOLINE 4000 WEL can be used

3. Softening (if needed)

…

…

…

…

…

…

…

…

…