Composite Polyester Film | Multi-layer Flexible Electrical Insulation Sheet for Dry-Type Transformers & Motors

Composite Polyester Film is a professional-grade, multi-layer flexible composite insulation material engineered for highly demanding electrical environments. It is manufactured by applying a specialized high-performance adhesive to a central core polyester film (PET) and laminating it with additional layers of polyester film on one or both sides to form a robust 2-layer or multi-layer configuration.

By combining top-tier raw materials and advanced thermal-bonding technology, delivers an unmatched balance of mechanical durability, high-voltage resistance, and long-term geometric reliability, serving as an essential component in heavy-duty industrial electrical apparatus.

Key Features & Advantages 

• Excellent Mechanical Properties: High tensile strength and elongation factors grant this film incredible resistance to tearing, cracking, and puncturing during automated industrial folding and forming processes.

• Superior Dielectric & Electrical Insulation: Provides outstanding breakdown voltage protection (up to ≥30 KV for thicker sheets), minimizing the risk of electrical leakage under continuous high stress.

• Outstanding Dimensional Stability: Keeps its precise physical layout and thickness uniform under structural mechanical compression and electromagnetic vibration.

• Reliable Thermal Bond Stability: Extensively tested under a demanding 180°C±2°C for 10 minutes heat cycle with zero instances of delamination, blistering, or adhesive flow.

Typical Applications 

Composite polyester film is widely specified across multiple sectors of industrial electrical engineering:

• Dry-Type Transformers: The premier material for section barriers and interlayer insulation partitions between high and low-voltage coils.

• Electric Motors & Generators: Excellently acts as motor slot insulation, phase-to-phase wraps, and structural separator cushioning.

• Electrical Appliances: Widely used as insulation linings and durable wraps for electromagnetic coils, reactors, and electrical control systems.