A collector for adjusting internal pressure of a writing implement offers improvements in deficiency prevention performance such as the capability of preventing ink leakage from occurring due to influence of the ambient pressure being varied during usage or when its cap is put on and off, the capability of preventing ink from erupting or leaking forward when the implement has been stored at a shop for a long period, and which still provides smooth writing comfort during writing. A collector (106) introduces ink through an ink channel (114) by the function of capillary action and temporarily holds ink in ink retaining grooves (113) and establishes air passage in the axial direction and radial direction by the combination of the air channel (115) and retaining grooves (113). The air channel is continuously formed so as to zigzag with a multiple number of turns with respect to axial direction of collector (106) by way of air channel parts (115a, 115b, 115c and 115d) and connecting passages (122a, 122b and 122c). This zigzagging configuration makes it possible to reduce ink eruption due to inrush of ink from the ink tank to the retaining grooves of the collector when a sharp change in temperature or pressure occurs.