| 摘要 |
<p>This invention relates to a dustproof cap (1) made by using mainly an unwoven electret cloth (2) having a surface charge density of not less than 1 x 10-10 coulomb/cm2 and a gas permeation rate of 10-1000 cc/cm2.sec. Although the cap according to the present invention has a comparatively simple construction, it has excellent dustproofing characteristics. The cap is remarkably effective in preventing the falling-off of hair, dandruff and dust. In addition, it has a high gas-permeability. Accordingly, even when a user wears this cap for a long period of time, he hardly feels stuffy. This cap can be used very effectively in various industrial fields which demand an environment in which the contamination due to the contaminants from the heads of workers and occupants should be prevented, such as the fields of food industry, electronic industry, precision machinery industry and medical industry.</p> |
