Abstract: A thermal head obtained by calcining a mixed material comprising at least ruthenium oxide particles having specific surface area of 10 to 45 m.sup.2 /g and a particle size of 1 .mu.m as the upper limit value of particle size distribution, glass fine particles and a dispersant which disperses these fine particles and disappears by calcining can reduce scattering of resistance values and give high image quality at thermal printing.

Abstract: A thermal head obtained by calcining a mixed material comprising at least ruthenium oxide particles having a specific surface area of 10 to 40 m.sup.2 /g and a particle size of 1 .mu.m as the upper limit value of particle size distribution, glass fine particles and a dispersant which disperses these fine particles and disappears by calcining can reduce scattering of resistance values and give high image quality at thermal printing.

Abstract: The present invention provides an electronic circuit component having a ceramic base and more particularly to a conductive paste for circuit film and an electronic circuit component having a copper film circuit of 10 .mu.m of less in film thickness formed from said conductive paste and a method for making the electronic circuit component.The characteristic of the present invention resides in a conductive paste comprising 100 parts by weight of copper powder of 1 .mu.m or less in average particle size, 0.01-4 parts by weight of at least one of S, Te and Se and 1-10 parts by weight of a frit glass as a binder.Further, there is provided an electronic circuit component having a copper film circuit containing 0.005-2 parts by weight of at least one of S, Te and Se and an effective amount of a glass as a binder for 100 parts by weight of copper which is produced by forming a circuit pattern of said conductive paste on an insulating base by flexo-printing method or the like and then firing the pattern.

Abstract: The first and second electrodes, to which a recording signal is to be applied, are printed to a desired pattern on an insulating substrate by, for example, a screen printing method. A heating resistor is formed by, for example, a screen printing method so as to be bridged over these first and second electrodes. A protective layer is formed so as to cover the first and second electrodes and heating resistor therewith. Each of the heating portions of the heating resistor is provided with one or a plurality of laser-made holes, and the resistance value of each heating portion of the heating resistor is regulated to a predetermined level on the basis of the number of the laser-made holes.