Abstract: An ink supply communication path is formed so that one end thereof is arranged outside a region confronting a pressure producing chamber at a region confronting a reservoir chamber; and an ink supply constricted port is arranged at a portion of the ink supply communication path, the portion being remotest from the pressure producing chamber. Since the pressure producing chamber is connected to the ink supply constricted port through the elongated ink supply communication path, a jet flow from the ink supply constricted port grows into a large flow along the ink supply communication path, which in turn allows air bubbles susceptible to stagnation in the vicinity of the ink supply constricted port to be discharged by such large flow.

Abstract: A method of producing active cathode material for lithium secondary battery is provided. In accordance with this invention, a mixture of a lithium salt and a transition metal salt is baked in oxygen atmosphere, wherein the oxygen pressure during baking is about 147.1 kPa or more. The lithium transition metal compound oxides prepared have the composition, Li.sub.x Ni.sub.y M.sub.1-y O.sub.2, wherein M is one kind of transition metal or more, and x and y respectively have the values 0.05.ltoreq.x.ltoreq.1.10 and 0.5.ltoreq.y.ltoreq.1.0. The active cathode material for a lithium secondary battery according to this invention, provides lithium transition metal compound oxides which are uniform in composition and characteristic, and exhibit excellent functioning as an active cathode material. Lithium secondary batteries produced therewith exhibit excellent cycle characteristics, high energy densities and low material costs, are of uniform quality and exhibit no unevenness of battery capacity.

Abstract: A non-aqueous liquid electrolyte secondary cell, in which Li.sub.x MO.sub.2, where M is at least one transition metal, preferably at least one of Co and Ni , with 0.05.ltoreq.X.ltoreq.1.10, and in which charging and discharging is carried out by doping and release of lithium, is disclosed. The non-aqueous liquid electrolyte secondary cell has a current breaking device operated responsive to rise in the internal pressure in the cell. The current breaking device is adapted to be actuated positively by adding lithium carbonate to the active material of the positive electrode and providing the active material with surface portion covered with lithium carbonate. Preferably, the amount of addition and the specific surface area of lithium carbonate are 0.5 to 15 wt % and not less than 0.1 m.sup.2 /g, respectively.

Abstract: A thermal print head comprises: a thermally resistant insulating substrate; a glazed glass partially formed on the substrate at one end side thereof; a heating element formed on the glazed glass; a first common electrode formed on the heating element; and a protective film formed on the first electrode; a second common electrode a part of which is formed between the insulating substrate and the glazed glass, the first and second electrodes being connected to each other; wherein the insulating substrate has a chamfer on the one end side where the first and second common electrodes are arranged, the chamfer being formed closely from the glazed glass, a part of the first and second common electrode being arranged on the chamfer.