| 摘要 |
<p>PROBLEM TO BE SOLVED: To fix foreign matter in a filter stuck to cover a venthole in such a way that no foreign matter is produced even under a violet airflow such as an air blow while ensuring air permeability and to capture finer foreign matter by impregnating a resin into the entire inner surface of the filter and >=50% of the volume of the filter. SOLUTION: A filter with a resin impregnated into the entire inner surface of the filter and >=50% of the volume of the filter is stuck so as to cover a venthole for air pressure regulation disposed in a pellicle frame. Foreign matter present in the micropores in the filter is reliably fixed in the production of the filter and little foreign matter is produced even under a strong air blow. Since foreign matter produced in the filter and foreign matter which enters the filter from the outside are captured by static electricity generated by friction between an air flow and the resin and by the micropores, foreign matter hardly enters the pellicle.</p> |
