Patent ID: 8684617

Claim:
A writing instrument comprising: a barrel including a visible part; an ink occlusion body disposed in said barrel, the ink occlusion body including a capillary material impregnated with ink; a pen tip including a capillary material disposed in a writing part of the writing instrument, and an ink guiding feed, wherein the ink impregnated in the ink occlusion body is fed to the pen tip via said ink guiding feed, a rear end part of said ink guiding feed joining to said ink occlusion body, and a front end part of said ink guiding feed joining to said pen tip; wherein said visible part of said barrel is defined generally between said ink occlusion body and said pen tip, said ink guiding feed being held within said visible part; wherein ink flows from the capillary material of said occlusion body by virtue of capillary force and ink flows into the capillary material of said pen tip by virtue of capillary force, said ink guiding feed lacking any capillary material therewithin; wherein said ink guiding feed is tubular and has a cross-sectional area of 0.5 to 20 mm 2 , and said ink guiding feed is disposed within the barrel between the ink occlusion body and the pen tip so as to prevent outside air from flowing in when the ink occlusion body is impregnated with ink, and allowing outside air to flow into the barrel as ink in the ink occlusion body is depleted; and wherein said ink guiding feed has visibility such that a sign of exhausting the ink fed from the ink occlusion body to the pen tip is detected by visually observing the empty ink guiding feed via said visible part formed in the barrel.