The Problem with Traditional Carriers
Conventional carriers (biphenyl, chlorobenzene derivatives) are used to swell polyester fibers for dye penetration at atmospheric pressure. However, they pose serious issues:
- Toxic fumes requiring expensive exhaust systems
- Environmental pollution — many are classified as hazardous waste
- Health risks for workers (skin irritation, respiratory issues)
- Odor contamination of finished fabrics
The Solution: Gropers DPE System
Gropers DPE is our APEO-free, carrier-free polyester dyeing auxiliary that achieves comparable results:
- Works at 98-100°C (atmospheric pressure)
- No toxic fumes or odor
- Compatible with all disperse dye classes
- Biodegradable formula
Comparison: Carrier vs. Carrier-Free
| Parameter | With Carrier | Gropers DPE | |-----------|-------------|-------------| | Temperature | 98°C | 98-100°C | | Color depth (K/S) | 18-20 | 17-19 | | Wash fastness | 4 | 4-5 | | Light fastness | 5-6 | 5-6 | | Worker safety | ⚠ Risk | ✅ Safe | | Wastewater | Hazardous | ✅ Clean |
Recipe for Dark Navy Polyester
- Levelling: Grogal PES — 1 g/L
- Dispersing: Gropers DPE — 3-5 g/L
- pH Buffer: Grocid BFF — 1 g/L (pH 4.5-5.0)
- Dye: Disperse Navy Blue — as required
- Temperature: Raise to 98°C at 1°C/min, hold 60 min
- Reduction clear: NaOH + Na₂S₂O₄ at 70°C, 20 min
ROI: Beyond Health & Safety
Switching to carrier-free dyeing also saves money:
- Elimination of carrier cost: €2-4/kg saving
- Reduced exhaust system maintenance
- Lower wastewater treatment costs
- OEKO-TEX and GOTS compliance
Request a trial batch with Gropers DPE — our technical team will guide you through the transition.