| 摘要 |
PURPOSE:To improve the liquid leakage resistance of a sealed alkaline battery by forming an insulating film composed of a metal oxide and silicon dioxide particles with specified diameter under an insulating coating film formed over the negative can. CONSTITUTION:Silicon dioxide particles 6 with 10-150Angstrom diameter are buried in minute holes (A) with 100-300Angstrom diameter formed in an insulating film 2d which is made of a metal oxide such as alumina or chromic acid and formed on the surface of the material 2a of a negative can 2 by vapordeposition or chemical treatment. The thus treated negative can 2 is then thermally treated at over 150 deg.C (preferably 400-600 deg.C) so that the silica particles 6 do not dissolve into water and the negative can 2 is not deteriorated with the passing of time and is highly alkali resistant. As a result, no defects or minute holes are formed over the entire surface of the negative can 2, thereby preventing water adhering to the surface of the negative can 2 from depolarizing and attracting electrolyte. Accordingly, the electrolyte does not migrate upward along the surface of the can 2 and the liquid leakage resistance of the battery is improved. |
