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SynTherm® – Insulating Materials

SynTherm® YT564 (metastar® YT564)

SynTherm® YT564 is a synthetic electro-insulation paper consisting of a calandered, aromatic polyamide fibride flock composition, good glue affinity and composite capacity.


SynTherm® YT564 is a class H (180 °C) insulating material. Temperatures below 200 °C only slightly influence its electrical properties. The good mechanical properties can be extrapolated to significantly higher temperatures. SynTherm® YT564 is also suitable for use at temperatures to -190 °C due to its polymer structure. It hs a high short-term dielectric strength.  SynTherm® YT564 is compatible with all classes of common resins, varnishes, adhesives as well as transformer liquids, lubricants, and cooling agents. Common solvents may lead to slight reversible moisture expansion. SynTherm® YT564 has low flammability (UL 94V-0) and very high resistance to beta and gamma radiation.


SynTherm® YT564 is suitable for compositing with polyester film and the polyimide film F- and H-class laminates.
SynTherm® YT564 is also used for wrapping copper or aluminium conductors.

  • Thermal class H (180 °C)
  • RoHS-compliant according 2011/65/EU
  • UL file no. E358562
  • UL listed (RTI mech. + electr. 210 °C)
Delivery forms

Film thicknesses in µm:
40, 50, 80, 130

SynTherm® YT564 is available:

  • in tapes: depending on material thickness on request beginning at 6 mm (thin material)
  • in rolls: 980 mm


  • Depth approx. 1-12 mm; distance approx. 1-10 mm
  • Form widths of 10 mm to 240 mm, thickness on request

Calandered, aromatic polyamide fibride flock composition

Technical data
Typical mechanical properties
Nominal thickness  Typical thickness  Specific weight  Tensile strength longitudinal  Tensile strength transversal  Elongation at break longitudinal  Elongation at break transversal  Shrinkage at 300 °C longitudinal  Shrinkage at 300 °C transversal  Elmendorf tear strength longitudinal  Elmendorf tear strength transversal 
Unit of measure         Test method 
µm  40 50 80 130  
µm  40 50 80 130 GB/T451.3-2002
g/m²  29 38 63 116 GB/T451.2-2002
N/cm  22 32 60 125 GB/T12914-2008
N/cm  8 14 25 50 GB/T12914-2008
4.5 5.5 7.0 8.5 GB/T12914-2008
5.0 6.0 8.0 10.0 GB/T12914-2008
4.4 4.4 4.0 3.5 IEC60819-2:2002
3.5 3.3 3.2 3.0 IEC60819-2:2002
0.50 0.70 1.20 1.70 GB/T455-2002
0.70 1.10 2.00 2.80 GB/T455-2002
Typical electrical properties
Nominal thickness  Field intensity 
Unit of measure         Test method 
μm  40 50 80 130  
kV/mm  11 12 12 12 GB/T1408.1-2006

SynTherm® is a registered trademark of SynFlex.

Corona information, 31.03.2020

Dear business partners,

Despite the progressing corona pandemic, we as SynFlex have succeeded to date in maintaining our business operations at all locations. We offer our customers the accustomed high level of service in terms of delivery flexibility and advisory competence and we maintain existing agreements with our suppliers. Our staff currently provide excellent services despite the many precautionary measures necessary to protect everyone's health. They are fully available to you, in administrative areas usually from a home office.

It remains to be seen how things will continue. Crisis management dominates. It is simply impossible to make serious forecasts about future economic and social changes. All forecasts are plain guessing.

Thus, the resolutions remain: maximum solidarity, responsible action and best possible maintenance of all structures. There will be a time after SARS-CoV-2!

In this spirit we wish you all much steadfastness and good health.

Your SynFlex Team