A Study on the Low Energy Consumption Thermal Head Using Electroless Ni‐W‐P Alloy Films as Heating Resistors

Abstract

The new type of thermal head with an electroless N i-W-P film on a poly imide film substrate was investigated for the purpose of low cost and low energy consumpt ion. The electroless plating method attained a fine patterned heating ele-ment and the poly imide substrate worked as a heat-insulating layer with a lower heat conductivity. In our simulation, the applied power was reduced about 50 % by using poly imide film as the heat-insulating layer. The accumulat ion of heat could be suppressed by controlling the polyimide film thickness without reducing the advantage oflow energy consump-tion. The new head, composed of screen-printed polyimide resin with SiC powder (10 ~m thick) as the protective layer, an electroless Ni-W-P film (0.25 i~m thick) as the heating element, a polyimide film (50 i~m thick) as the heat-insulating layer, and an A1 board (3.0 mm) as the heat sink, was produced. The new head shows the same dot size as that of the conventional thin-film-type head produced by vacuum technology, and its cost is lower than that of the conventional thin-film-type head. The new head produces the good printing quality with 60 % of the power required by the conventional one. There-fore, the new head provides low cost and low energy consumpt ion. Recently, thermal printing systems have been widely ap-plied to facsimiles and printers (1, 2). Especially for facsim-iles of medium speed, thermal printing is generally used