PI Film Thermal Control Grade Suppliers: Selection Guide and Market Landscape (2026)

PI Film: Core Material for Flexible Electronics and Thermal Control

Polyimide (PI) film has become the core substrate for flexible circuits (FPC), thermal control materials, and aerospace insulation materials due to its excellent high-low temperature resistance (-269℃～400℃), low dielectric constant, high dielectric strength, and excellent dimensional stability. In 2026, with the explosive growth of new energy vehicles, foldable smartphones, and 5G communications, demand for thermal control grade PI film is surging, and high-quality supplier resources are scarce.

Thermal Control Grade PI Film Core Technical Indicators

• Thermal Conductivity: Ordinary PI film 0.12-0.2 W/(m·K), thermal control grade PI film can reach 1.5-5 W/(m·K) by filling with thermal conductive fillers
• Temperature Rating: Long-term operating temperature -269℃～400℃, short-term can withstand 500℃
• Dielectric Constant: Dk=3.0-3.5 (1MHz), low dielectric loss Df<0.002, suitable for high-frequency high-speed transmission
• Dimensional Stability: CTE≤15 ppm/℃, coefficient of thermal expansion close to copper foil, reducing FPC warpage
• Thickness Range: 12.5μm-125μm (ultra-thin type), 125μm-250μm (conventional type)

2026 PI Film Market Landscape

The global PI film market shows an oligopoly pattern:

1. DuPont (USA): Kapton® series, ~35% global share, leader in high-end market
2. Kaneka (Japan): Apical® series, ~25% share, strong competitiveness in high-end electronics
3. SKC (Korea): ~15% share, significant advantages in display field
4. Taimide Tech (Taiwan): ~8% share, deep cultivation in FPC substrate field for many years
5. Domestic Manufacturers: Rayitek, Times New Material, DandB Technology, etc. are accelerating catch-up, thermal control grade products have been supplied in batches

Thermal Control Grade PI Film Supplier Selection Points

When selecting PI film thermal control grade suppliers, it is recommended to focus on the following evaluation dimensions:

• Thermal Performance Guarantee: Whether tested according to ASTM D5470 standard, whether thermal conductivity data is traceable
• Thickness Uniformity: Whether thickness deviation within the same roll is controlled within ±2μm, affecting FPC processing yield
• Surface Quality: Whether there are defects such as pinholes, bubbles, scratches, affecting insulation reliability
• Batch Consistency: Key performance indicators (thermal conductivity, dielectric constant, CTE) batch fluctuation ≤3%
• Custom Development Capability: Whether supporting formula optimization, thickness customization, surface treatment (plasma, corona, etc.)

Application Fields and Selection Recommendations

1. New Energy Vehicles: Motor insulation materials, battery module thermal pads, recommend 125μm+ thick film, temperature resistance ≥200℃
2. Foldable Smartphones: Flexible cover film, thermal film, recommend 25-50μm film, bending life ≥200,000 cycles
3. 5G Communications: Antenna substrate, high-frequency FPC, recommend low dielectric PI film (Dk≤3.2)
4. Aerospace: Insulation laminate materials, recommend special PI film with temperature resistance ≥300℃

Procurement Strategy Recommendations

• Tiered Procurement: High-end applications (aerospace, high-end FPC) select DuPont/Kaneka imported products; mid-end applications (consumer electronics, automotive) can import domestic PI film
• Supplier Certification: Establish qualified supplier list, conduct regular on-site audits and performance verification
• Strategic Stock: Thermal control grade PI film delivery cycle 8-12 weeks, recommend maintaining 2-3 months safety stock
• Cost Optimization: Annual framework agreement to lock prices, negotiate 10-15% discount for bulk purchases

For FPC manufacturers, new energy enterprises, and electronic module factories, 2026 is a critical year for PI film supply chain optimization. It is recommended to establish a safe, efficient, and low-cost PI film supply system through supplier diversification, domestic substitution verification, and strategic inventory management.

Keywords: PI film thermal control grade suppliers, polyimide film, thermal control materials, FPC substrate