Kapton® 120FMT616 Thermally Conductive FEP-Coated Polyimide Film
Kapton® 120FMT616 is a thermally conductive Kapton® film with three times the thermal conductivity of standard Kapton®, combined with low moisture permeation, high temperature resistance, and high tear strength, at a nominal thickness of 1.15 mils. The film is constructed of a 1.0 mil (25 µm) thermally conductive Kapton® base film with a 0.1 mil (2.5 µm) FEP coating on both sides, combining thermal management performance with moisture barrier and electrical insulation properties.
Key Properties
- Tensile Strength: 19 kpsi — ASTM D882
- Elongation: 67% — ASTM D882
- Dielectric Strength: 5200 V/mil — ASTM D149
- Tear Strength: 2.3 lbf — ASTM D1922
- Nominal Thickness: 1.15 mils — ASTM D374
- Water Vapor Permeation: 17.5 g/(m²·24h) — ASTM D96
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- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Typical Value | Test Method |
| Nominal Thickness, mils | 1.15 | ASTM D374 |
| Tensile Strength, kpsi | 19 | ASTM D882 |
| Tensile Modulus, kpsi | 475 | ASTM D882 |
| Elongation, % | 67 | ASTM D882 |
| Tear Strength, lbf | 2.3 | ASTM D1922 |
Electrical Properties
| Property | Typical Value | Test Method |
| Dielectric Strength, V/mil | 5200 | ASTM D149 |
| Dielectric Constant | 3.1 | ASTM D150 |
| Dissipation Factor | 0.0015 | ASTM D150 |
Chemical Properties
| Property | Typical Value | Test Method |
| Moisture Absorption, 50% RH, % | 1.3 | ASTM D570 |
| Moisture Absorption, 98% RH, % | 2.5 | ASTM D570 |
| Water Vapor Permeation, g/(m²·24h) | 17.5 | ASTM D96 |
- Heater insulation requiring thermal conductivity through the dielectric layer combined with moisture barrier properties
- Flat panel heater substrate applications where an FEP-coated thermally conductive film is needed
- High temperature insulating wraps where moisture resistance and elevated thermal conductivity are simultaneously required
- Flexible electrical insulation in heater circuit constructions bonded via the FEP layer
- Thermal management insulation pads where a heat-fusible, thermally conductive polyimide film replaces less flexible alternatives
Common industries: industrial heating systems, electronics, flat panel manufacturing, thermal management systems, aerospace.
Kapton® 120FMT616 combines the thermal conductivity of the Kapton® MT series with FEP fluoropolymer coatings on both sides, creating a film suited for heater insulation and flat panel heater substrate applications where thermal conductivity through the dielectric layer, moisture resistance, and high temperature performance are simultaneously required.
The 0.1 mil FEP layer on each side of the 1.0 mil thermally conductive polyimide core contributes to the film’s low moisture permeation characteristics — moisture absorption is 1.3% at 50% RH and 2.5% at 98% RH — while retaining the heat resistance and flexibility expected of the Kapton® film family.
Electrically, the film provides 5200 V/mil dielectric strength with a dielectric constant of 3.1 and a dissipation factor of 0.0015. Tear strength of 2.3 lbf supports reliable handling and processing. The film is designed for applications including heater insulation, flat panel heater substrates, and high temperature insulating wraps where the combination of thermal conductivity, FEP coating, and polyimide durability delivers performance that neither material alone would provide.
What differentiates Kapton® 120FMT616 from standard Kapton® MT?
Kapton® 120FMT616 adds a 0.1 mil FEP fluoropolymer coating to both sides of the thermally conductive Kapton® base film, which introduces moisture barrier properties and the potential for heat-fused bonding not present with bare MT film. Standard Kapton® MT provides thermal conductivity and cut-through strength without the FEP layer, making it better suited for dry slip-fit installations; 120FMT616 is preferred where moisture resistance or heat-fused assembly is required.
Why does tensile strength matter for heater film substrate selection?
Tensile strength determines how well the film survives handling, winding, lamination, and forming operations during heater circuit manufacturing, and how it performs under the mechanical stresses present in the end-use environment. Kapton® 120FMT616 at 19 kpsi provides the toughness expected of polyimide film substrates while the FEP coating adds additional handling protection.
What is the service temperature capability of Kapton® 120FMT616?
The TDS characterizes Kapton® 120FMT616 as having high temperature resistance and the thermal conductivity of the Kapton® MT series, with the FEP coating on both sides. No specific rated service temperature is stated on the H-O Products TDS for this material. Contact H-O Products for additional thermal performance data.
Is Kapton® 120FMT616 suitable for regulated environments?
No compliance certifications are specified on the H-O Products TDS for Kapton® 120FMT616. Contact H-O Products for additional compliance information.
How should Kapton® 120FMT616 be specified?
Specify grade (Kapton® 120FMT616), nominal thickness (1.15 mils), compliance requirements, dimensional tolerances, and finished format (slit roll, sheet, or die-cut component).
