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SynChem – Resins & Varnishes

Voltatex® 4204 1-component impregnating resin

Voltatex® 4204 is a low emission, environmentally friendly, ready-to-use impregnating, yellowish 1K dip resin based on unsaturated polyesterimide resins.

  • single component
  • low emission
  • very low viscosity
  • environmentally friendly
  • minimum exposure in the working area
  • no risk of fire or explosion
  • based on renewable raw materials

The cured resin compound is characterised by:

  • very low tendency to crack
  • very good adhesion
  • electric motors
  • generators, also for large drives
  • transformers
  • in particular for mica tape insulated flat rolled litz wires
  • suitable for: insulation systems of thermal class 180 (H)
  • suitable for applications in medium and high voltage area
  • UL approved, file no.: E 101752 (M) Unterwriters Laboritories Inc., USA
  • Temperature Index 180 (H) in acc. with IEC 60085
  • RoHS-compliant 2011/65/EU
  • Polybromited diphenylether 2003/11/EU
  • REACh-compliant 2006/121/EU
  • UL 1446 approved:
Twisted Pair ASTM D2307 MW 35:180
    MW 80:155
Helical Coil ASTM D2519 MW 35:200
    MW 80:180





Delivery forms

Voltatex® 4204 is supplied in one-way-cans containing 25 kg or 200 kg.


The resin can be stored for up to 6 months at max. 25 °C if sealed correctly in original containers. Opened containers have to be resealed and protected against direct sunlight!


Voltatex® 4204 is a low emission product, nevertheless to minimize evaporation of reactive components during curing; the impregnated objects should be heated up to curing tempera-ture in the shortest possible time. The air flow in the curing oven should also be kept to the minimum permitted by safety considerations.

Curing times:

Dip & Bake Process 130 °C 2 h
  150 °C 1 h
Trickle Feed Process 130 °C 15-30 min.
  150 °C 15-20 min.

Cured Voltatex® 4204 is biologically inactive and not dangerous to health. When processing the liquid resin, please refer to the Material Safety Data Sheet (MSDS) for Voltatex® 4204.


Cured Voltatex® 4204 is almost insoluble. Therefore, application equipment should be regularly cleaned with cleaner Voltatex® T050. All equipment cleaning and maintenance should be carried out in accordance with the equipment manufacturers instructions.


The impregnating resin can be applied by using

  • all kind of conventional dip & bake equipment
  • continuous, vacuum dip and VPI processes
  • dip & roll equipment
  • trickle feed machines

Unlimited tank stability with resin Voltatex® 4204 can be achieved as long as the material is kept below 25 °C and at least 20 % of the tank content is used and replaced with fresh resin per month.

Technical data
Bond strength of twisted coils room temperature  Bond strength of twisted coils 155 °C  Shore D hardness room temperature  Water absorption  Glass transition temperature  Volume shrinkage 
Unit of measure Values  Test method 
200 ± 40 IEC 60455-2, test method A acc. IEC 61033
57 ± 10 IEC 60455-2, test method A acc. IEC 61033
  76 ± 5 IEC 60455-2, test method acc. ISO 868
0.6 Company standard Energy Solutions-015, acc. ISO 62
°C  app. 50-130 DSC-method
8.6 Company standard Energy Solutions-003
Resistance  Resistance 
Conditions  Values  Test method 
Distilled water, transformer oil resistant IEC 60455-2, test method acc. ISO
solvent vapours under test company standard Energy Solutions - Voltatex® 019
Liquid phase
Impact on enamelled wires  Viscosity  Viscosity  Reaction process gel time  Reaction process reaction time 
Unit of measure Conditions  Values  Test method 
    compatible with all common magnet wires IEC 60851-4
mPas  at 25 °C 315 ± 25  
mPas  at 40 °C 130 ± 25 DIN 53019
min  100 °C 9.6 company standard Energy Solutions-014
min  100 °C 11.6 company standard Energy Solutions-014
Dielectric strength at 23 °C and 50 % r.h.  Dielectric strength at 155 °C  Dielectric strength at 23 °C after 96 h storage at 92 % r.h.  Dielectric strength at 105 °C after 168 h oil immersion  Specific volume resistance at 155 °C  Specific volume resistance at 180 °C  Specific volume resistance after 7 d water immersion  Creep resistance  Dielectric constant at 23 °C between 50 Hz and 1 MHz  Loss factor at 155 °C and 50 Hz  Loss factor cross section 0.2=200x10^-3 
Unit of measure Typ. values  Test method 
kV/mm  70 IEC 60455-2, test method acc. IEC 60243-1
kV/mm  60 IEC 60455-2, test method acc. IEC 60243-1
kV/mm  52 IEC 60455-2, test method acc. IEC 60243-1
kV/mm  67 IEC 60455-2, test method acc. IEC 60243-1
Ω*cm  3.6x10^10 IEC 60455-2, test method acc. IEC 60093
Ω*cm  3.5x10^10 IEC 60455-2, test method acc. IEC 60093
Ω*cm  1.8x10^15 IEC 60455-2, test method acc. IEC 60093
  CTI 600 M IEC 60455-2, test method acc. IEC 60112
  3.8 ± 0.6 IEC 60455-2, test method acc. IEC 60250-1
  150x10^-3 IEC 60455-2
°C  178 IEC 60250, between 50 Hz and 1 MHz

Voltatex® is a registered trademark of Axalta Coating Systems Llc., Philadelphia PA 19103, USA.