Introduction To The Manufacturing Process Of Thick Film Heaters
Preparation of stainless steel substrate
The uncoated stainless steel substrate must be cleaned of contaminants (such as fingerprints, dust, oil stains, grease, etc.), and gloves must be worn when the stainless steel substrate needs to be touched again once the cleaning is completed.
Printed insulating medium
ESL's insulating medium is printed on the corresponding stainless steel substrate by screen printing. We recommend using 165 mesh latex-free stainless steel screen for printing, and the sintered thickness of each layer should be controlled between 25-30 microns. You can use a film thickness tester to measure the thickness of the insulating medium. The three-layer separately sintered insulating medium slurry will reach a thickness of 80 microns or more to ensure sufficient insulation. Please perform the printing and sintering process in a dust-free and clean environment to avoid the appearance of small holes caused by fine impurities, which may cause a drop in the breakdown voltage. The slurry is dried at 125°C and sintered at 850°C.
Printed conductor
ESL conductors are printed on the insulating medium by means of screen printing. We recommend using 325 mesh 20 micron latex thickness stainless steel screen for printing. The method of drying and sintering is the same as the insulating medium or refer to the product specification.
Printed resistance
ESL 29XXX resistor paste is printed on the insulating medium by screen printing. We recommend using 250 mesh 5 micron latex thickness stainless steel screen for printing. In general, the width of the resistor printing is 2.4 mm, the thickness is 21±1 microns, and the spiral pattern is 178 squares. The method of drying and sintering is the same as the insulating medium or refer to the product specification.
Printed glass protective glaze
We recommend using a 165 mesh latex-free stainless steel screen to print the corresponding isolation media as a protective layer. The method of drying and sintering is as described above. It is inevitable that the resistance value of the resistor will change after sintering, but this will not affect normal use.
