| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable ink supplying device equipped with a filter device that does not allow instability in discharge and insufficiency in refill of ink to occur and also to provide an ink jet recording head by a method wherein the structure is made up so that bubbles are not produced at places near a filter of a filter box and the bubbles, if produced, are disappered instantaneously. SOLUTION: For an ink supplying device having an ink passage for making an ink housing part for housing ink and a discharge part for discharging the ink communicate with each other, the ink passage is equipped with a filter device having a filter and a filter box 6 for housing the filter and being equipped with an ink inlet and an ink outlet. While an area at the ink inlet side of the filter box 6 is arranged at a position below an area at the ink outlet side of the filter box 6, the inside diameter of the ink passage is narrowed at the ink inlet side of the filter box 6 so that it becomes smaller than the inside diameter of the ink passage immediately before a position where the inside diameter is widened in a trumpet shape toward the filter. |
