Thick film heaters

Thick Film heaters are based on the long-time technology used for production of printed circuit boards and hybrid circuitry. Heaters are built by applying a number of layers of dielectric, resistive and conducting pastes onto a leveled substrate. By selection of paste composition and processing conditions it is possible to control the specific resistance, TCR, TCE and adhesion properties of the Thick Film layer in order to fit with a large range of element design specifications. Thin cross-section and low mass make Thick Film elements compact in size and light in thermal capacity, meaning quicker heat up rate, improved controllability and economy to the consumer. Direct contact between the heating circuit and the substrate maximizes the heat transfer allowing high power densities. Flexible circuit design makes possible to distribute the power according to many different specifications getting a strict control of temperature pattern. Thick Film heaters are suitable for incorporating additional element functionalities like PTC/NTC sensors. The ability to generate flat elements makes possible to use them as a structural part of the application, saving space and costs and improving the esthetical feature of the final product. When the Thick Film resistor paste is formulated to undergo a large and sharp increase of resistance at a designated «switch» temperature, the power consumption is optimized to balance the heat subtracted by the surroundings, keeping the heater at the designed thermal condition and preventing device overheating.

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