| 摘要 |
PURPOSE:To enable a thermal head to be used also for gradation recording by decreasing scattering of resistance values among respective heating elements constructing a heating resistor, by a method wherein after trimming resistance values of each heating resistor interposed between an independent common lead electrode and an individual lead electrode within a specific range, the independent common lead electrode is formed again into a common electrode. CONSTITUTION:Independent common electrodes 2a-2d and individual lead electrodes 3a-3c are alternately formed on an insulating base board 1. Then, a heating resistor layer 4 is formed on each electrode obtained by screen printing and baking of resistant paste, a mixture of RuO2 and glass frit. Thereafter, an overloaded voltage pulse is applied between, for instance, a common lead electrode 2a and an individual lead electrode 3a, and a resistance value of a heating element 5 is corrected within a specific range or at a target value. Then, this operation is executed to each heating element. Then, for instance, band electrodes of Au is respectively connected to independent common led electrodes 2a-2d,... by printing or vapor deposition to form a comblike common electrode 2. |
