摘要 |
A dielectric substrate for a thin film dot matrix thermal print head has its working surface etched or otherwise treated to selectively remove the dielectric material, in all areas which will constitute electrical connectors for the resistance heater print elements, to a depth at least equal to the sum of the thicknesses of all of the conductive films to be applied to the substrate surface in those areas, following which the working surface of the substrate is selectively coated with films of high-resistance electrically conductive material and low-resistance conductive material, with suitable adhesion films as required, to complete the print head. An outer protective wear-resistant film is also employed. The resultant print head has its resistance heater print elements and blank surface elements raised at least to the same level as the outer surfaces of the electrical connectors, and preferably slightly higher, to provide improved performance and operating life. |