| 摘要 |
<p>PROBLEM TO BE SOLVED: To rapidly discharge the bubbles included in a photoresist to a drain hole by forming the base of a cap so as to incline at a specified angle, forming an inflow hole and a discharge hole in the positions where the heights thereof are the same and forming the drain hole in the position upper than the inflow hole and the discharge hole. SOLUTION: A slope 23 inclined at the specified angleαis formed on the base of the cap 17 formed with the inflow hole 18, the discharge hole 19 and the drain hole 20. The inflow hole 18 and the discharge hole 19 are formed at the points existing on the horizontal line of the slope 23. These holes are formed preferably in the position lower than the slope 23. The drain hole 20 is formed on the slope 23 existing on the upper side of the inflow hole 18 and the discharge hole 19. The angleαof the slope 23 formed on the base of the cap 17 is preferably set within a range of 5 to 20 deg.. As a result, the bubbles remaining in a filter housing 11 are rapidly discharged through the drain hole 20 existing on the space part side of the wide sectional area by the principle of moving from the place of a large pressure to the place of a small pressure.</p> |
