Transformer Insulation Materials
DDM Diamond Dotted Mylar®
Class B PET film with diamond-pattern epoxy dots on both faces
Electrical polyester film with a diamond-shape epoxy resin dotted on both sides. The latent hardener only activates on heating, so the film can be positioned first and bonded later - the standard inter-turn insulation for voltage transformers.
Class B (130°C)0.075–0.25 mmBreakdown ≥7 kV
- Temperature class
- Class B (130°C)
- Thickness
- 0.075–0.25 mm
- Width
- 5–1000 mm
- Adhesive
- 17.5 ±2.5 µm per side
Request a quotation or a sample. Tell us thickness, width, temperature class, quantity and delivery form. We reply within one business day.
Technical data
| Property | Unit | Value |
|---|---|---|
| Thickness | mm | 0.075 / 0.10 / 0.125 / 0.188 / 0.25 |
| Single-side adhesive thickness | µm | 17.5 ±2.5 |
| Thickness deviation | mm | ±0.007 |
| Thermal shrinkage | % | ≤3 |
| Tensile strength | MPa | ≥150 |
| Elongation at break | % | ≥80 |
| Breakdown voltage | kV | ≥7 |
| Width | mm | 5–1000 |
| Temperature index | — | ≥130 |
| Temperature class | — | Class B (130°C) |
Values are typical values or ranges from our product data. Bulk supply is subject to the approved specification, sample and test report. If a parameter you need is not listed here, ask our engineers for the full test report for that grade.
Key features
- Diamond dot pattern preserves film flexibility and interlayer air paths.
- Latent hardener activates on heating for fast positioning and bonding.
- Rolls, sheets or die-cut pieces for instrument-transformer winding and lamination.
Applications
Turn insulation in voltage transformers; layer insulation in small transformers and reactors.
Instrument TransformersOil-Immersed TransformersReactors
Why it fits
Dry, crisp and tack-free before curing - clean handling on automatic and manual winding lines alike.
Ordering information
To receive a quotation, please confirm:
- Product and grade
- Thickness and width (and roll or sheet size)
- Temperature class
- Quantity and delivery form (roll / sheet / die-cut / machined)
- Destination port and required delivery date
For machined parts, attach a drawing in PDF, DWG or STEP format. Datasheets, COAs and batch test data are available on request.
Related materials
Often specified together
Send your specification
Our export team reviews the application, the process and the existing specification before recommending a construction.