Polyimide Insulated Heating Film
Polyimide (Kapton®) is an organic film with very high dielectric capability, thin flexible profile and low thermal mass, while providing superior resistance to most solvents, acids, and radiation. In connection with these features, Polyimide heaters (also called kapton heater ) are very ideal for applications:
- with space and weight limitation: total thickness≤0.2mm; bending radius≥0.8mm
- be exposed to chemicals or oil
- in vacuum environments requiring low out-gassing
- fast and precise heating
Being transparent, Polyimide (Kapton®) film also allows easy visual inspection for the internal foil structures.
Polyimide heaters make use of very thin (e.g. 50μm) etched metal foil as resistance element. The material of the metal foil can be Kanthal, Copper, constantan, Ni, NiFe, NiCr, etc. Some of the materials may have MOQ requirement. Please consult us when order if the choice is critical for your application.
Taking advantage of the etched foil technology, complicated thermal profiles and wide range of resistance (from 1 Ω) can be realized. This feature is very valuable when small size and low voltage heaters are expected.
We are pretty good at the tolerance control of the heater resistance / wattage. Some customers order our polyimide heaters as heat source for their thermal simulation test. In this case, the resistance tolerance will be less than 2%.
Custom Options for Polyimide Heaters
Low Voltage e.g. 12V heaters are often required for instruments and electronics heating when 230V is not available. Low voltage supply often means low ohm value. Sometimes copper foil has to be used due to the low resistivity.
Multiple Heating Zone with different watt density is necessary in some application to achieve uniform temperature distribution, e.g. stabilize optoelectronic components.
Dimensions We normally leave 1mm from the heater film edge as clearance distance. Exit pads also take some space. So normally the width of the polyimide heater should not be less than 6mm. The maximum size of the heater is only limited by the width of the incoming polyimide film, typically 500mm. Holes and cutouts can be configured as specified.
Foil Backing and adhesive tape are optional for installation. Aluminum foil backing is recommended if you want to optimize the heat distribution. Metal foil shielding can be laminated on the top to reduce the emf noise.
Bifilar meander arrangement can reduce the parasitic inductance in the circuit as much as possible.
Temperature Sensor Thermistors and thermal cutoffs are the most frequently configured temperature sensors for polyimide heaters. Film thermistors are superior to SMT type as the leads connections are more robust for handling and installation.
Leads & Solder Pad Teflon cable leads are normally configured. The specific AWG depends on the current draw. Special cord set can be integrated as well. Solder pad is a good option when the space is limited and the customer wants to solder the wires by themselves.
Application of kapton heaters
- Medical diagnostic instruments: Heat sample trays, reagent bottles, ventilator humidifier, etc.
- Stabilize optoelectronic components
- Test or simulate integrated circuits
- Enable cold weather operation of outdoor electronics such as laptop, light box, ATM, LCD
- Protect aircraft electronic and mechanical devices in cold weather / area