| 摘要 |
PURPOSE:To make it possible to surely detect the presence of diffusion paper by noncontact detecting method by coloring a part or the whole of air diffusion paper to form a difference in gloss between the paper and a case. CONSTITUTION:A positive case 1 has one or more holes 2 near the periphery of the bottom and a recess serving as an air room. Air diffusion paper 3 colored in black is placed in the recess. The presence of the air diffusion paper is perfectly detected with an infrared reflex type phototube compared with colorless (white) air diffusion paper, and detection failure is completely eliminated. Therefore, a button type air cell having steady quality can be provided. |
