Patent ID: 7073967

Claim:
A writing instrument including an ink intake retainer body for temporarily storing ink of an ink tank and then supplying the ink, a tubular drawing tip for drawing the ink of the ink tank by way of a capillary phenomenon for writing purpose, and an air passage through which air for enabling the ink to flow from the ink intake retainer body to the tubular drawing tip passes, comprising: an ink drain restriction body for temporarily storing the ink introduced because of volume expansion, shock flow, etc. and then supplying the ink, wherein the ink drain restriction body is disposed on the air passage of the ink intake retainer body, and is formed using a foam having large porosities and a low density such that the absorption force of the ink drain restriction body is lower than that of the ink intake retainer body, further comprising a retaining tubular cap for precluding the ink introduced due to volume expansion or shock flow, wherein the retaining tubular cap is provided in the rear of the ink drain restriction body.