Integrated thermal printing head and method of manufacturing the same

A thermal printing head comprising:

• a first thick-film heat insulating layer laid over the flat main surface of an insulating substrate, said heat-insulating layer being made of glass ceramic of a high softening point;
• at least two sets of thick-film lead electrodes, one of said sets including two opposed thick-film lead electrodes provided over said first heat-insulating layer;
• a second thick-film heat-insulating layer having a thickness near that of said thick-film lead electrodes and made of glass having a softening point lower than that of said first heat-insulating layer so as to provide flat top surface, said second thick-film heat-insulating layer being positioned between said opposed thick-film lead electrodes;
• thin-film heating resistors provided on said second heat-insulating layer in number commensurate with the number of sets of said thick-film lead electrodes;
• a thin-film lead electrode electrically connecting the opposite ends of said heating resistor to said thick-film lead electrodes;
• and oxidation-preventive film covering said thin-film resistors and said thin-film lead electrodes;
• and a protective layer coated over said oxidation-preventive film.

An integrated thermal printing head, comprising:

• a dielectric substrate having a flat main surface;
• a heat insulating dielectric layer formed in part of a region of said main surface;
• at least two first thick-film lead electrodes screen-printed on said substrate in opposed relation on one side of said heat insulating layer region;
• a dielectric layer for use in a matrix wiring, which is formed on said substrate so as to coat the ends of said first lead electrodes on the other side;
• at least two second thick-film lead electrodes screen-printed on said dielectric layer for said matrix wiring, in a manner to connect with said first respective lead electrodes through a through-hole provided in said dielectric layer for said matrix wiring;
• at least two third thick-film lead electrodes screen-printed on said substrate in opposed relation to the other side of said heat insulating layer;
• a common, electrically conductive layer formed on said substrate in a manner to electrically connect with said third lead electrodes;
• at least two thin-film resistors formed on said heat insulating dielectric layer in a manner to provide a spacing smaller than that of the arrangement of said first and third thick-film lead electrodes with reference to the center line thereof;
• and, at least two first thin film lead electrodes which electrically connect the ends of said respective resistors on one side, to said first respective lead electrodes;
• and at least two second thin film lead electrodes which electrically connect the other ends of said respective resistors to said third respective lead electrodes.