Thermoforming Polyimide Film - for Uniform 3D Forming with Balanced MD/TD Behavior

Thermoforming Polyimide Film  PKF - Engineered for Uniform 3D Forming with Balanced MD/TD Behavior

Product Description: 

Our PKF is a Biaxially Oriented Thermoformable PI film specifically developed for advanced thermoforming applications. It is engineered specifically for uniform thermoforming behavior, featuring balanced mechanical response in both MD and TD directions, enabling reliable 3D shaping at elevated tempertures without localized deformation, cracking or shrinkage.

Unlike conventional PI films, PKF is engineered to be thermoformable into complex three-dimensional geometries while maintaining PI's intrinsic performance characteristics. It successfully combines the outstanding heat resistance stability, mechanical strength, and electrical insulation of standard polyimide with enhanced formability, enabling precise shaping without cracking, wrinkling, shrinkage, or performance degradation.

Thermoforming & Processing Characteristics:

PKF achieves optimal forming performance at lower processing temperatures between 270°C to 330°C, and forming pressures of approximately 1 MPa (10.2 kg/cm²) with shorter cycle times. It is well suited for drawing and thermoforming processes, allowing the film to be shaped into solid and complex components with high dimensional accuracy. 

Thanks to its biaxially oriented structure, PKF offers uniform forming behavior in both the machine direction (MD) and transverse direction (TD), enabling stable, deep, and consistent formation of irregular and three-dimensional shapes.

Key Properties:

1. Lower thermoforming Temperature and Pressure compared to other formable PI films.
2. Uniform forming performance in both TD and MD directions.
3. Outstanding elongation behavior under heat and pressure.
4. Lower glass transition temperature (Tg).
5. Excellent thickness uniformity in both MD and TD directions.
6. High dielectric strength and reliable electrical insulation.
7. Excellent high-temperature resistance suitable for demanding environments.
8. RoHS & REACH SVHC compliant, meeting all current EU environment mandates.
9. UL 94 V-0 , VTM-0 Certified.

   
   

   
   

Design Challenge in PI Thermoforming:

As electronic devices continue to evolve toward thinner profiles, complex 3D geometries, and higher functional integration, conventional rigid or non-formable polyimide films face significant limitations. These materials struggle to conform to curved surfaces, deep-drawn or three-dimensional structures without cracking, wrinkling, or inducing internal stress, resulting in restricted design freedom, increased assembly complexity, and reduced long-term reliability.

Engineers working with conventional PI films in thermoforming processes often encounter:

• Non-uniform deformation between MD and TD directions

• Local thinning, wrinkling, or stress concentration

• Cracking or tearing at corners and high-curvature regions

• Shape inconsistency across production lots

• Low yield despite correct forming temperature and tooling

In many cases, these failures are not tooling issues, but the result of anisotropic film behavior during forming.

Our Solution Approach: 

PKF is engineered to behave as a true thermoforming-grade PI film, with controlled and balanced mechanical properties, featuring:

• Uniform thermoformability in both MD and TD directions
  Enabling isotropic deformation during forming

• Reduced anisotropic stress accumulation
  Minimizing localized thinning and crack initiation

• Stable forming window
  Supporting consistent shaping across temperature and pressure variations

• Predictable thickness distribution after forming
  Improving dimensional accuracy and functional consistency

Unlike conventional PI films that are merely “formable,” PKF is designed to be thermoformable by engineering definition, not by process compromise.

Why MD/TD Balance Matters in 3D Forming

Thermoforming failures often originate from directional imbalance, where:

• MD stretches while TD resists

• Stress concentrates at transition zones

• Deformation becomes tool-dependent rather than material-controlled

By engineering balanced MD/TD response, PKF allows the material—not the tooling—to define the forming behavior, resulting in smoother stress distribution and higher process robustness.

What Reliable 3D Forming Looks Like with PKF Film  

                                                       Shown with actual thermoformed 3D parts made from PKF Film

PKF is engineered to undergo controlled thermoforming without inducing stress concentration, micro-cracks, or thickness instability, enabling reliable 3D shaping for functional and structural applications.

Major Applications:

1. Acoustic components, acoustic diaphragms, speaker cones, domes. 
2. EV Battery Cell Safe Spacers (Tray / Sleeve type).
3. Embossed parts and precision-formed parts for aerospace and high-performance industrial applications.
4. 3D flexible printed circuits (3D FPCs)  for wearable electronics, such as smartwatches and AR/VR headsets, where space is    extremely limited and circuit layouts must conform to complex shapes.
5. 3D electronic assemblies and structural components, including automotive capacitive touch sensors integrated into curved    interior or exterior trim parts.
6. Custom-shaped insulation components for diagnostic equipment, and wearable devices.
7. 3D Insulators: Insulation for transformers, capacitors, formed coil and magnet wire.
8. Semiconductor Components.
9. Thrust washers, and precision gaskets.

Application Cases:

I. Thermoformed PI Diaphragm for Automotive & High-Performance Audio Applications

Advanced thermoformed polyimide diaphragm integrated within a premium automotive speaker system, delivering precise acoustic performance, structural stability, and long-term thermal reliability.

II. Thermoformed PI Micro Structures

PKF thermoformed film delivers high-fidelity micro structures with excellent dimensional consistency across the entire roll. Designed for precision replication, it ensures uniform geometry, stable performance, and scalable mass production for advanced engineering applications.

III. 3D Formed PI Components for Safer EV Battery Systems

Advanced thermoformed polyimide (PI) components engineered for EV battery systems, delivering reliable thermal isolation, electrical insulation, and structural protection to enhance safety and long-term performance.

Available Sizes:

 Film Thickness: 75µm,100µm, 125µm

 Roll Width: 520mm, 1040mm

 Optional surface treatments can be provided to meet specific downstream processing or application requirements.

Designing components requiring reliable and uniform PI thermoforming?

Contact us to discuss Thermoforming PI Film (PKF) solutions optimized for your geometry, forming conditions, and production requirements.