Writing implement refill and writing implement

摘要

A problem to be solved is to provide a writing implement at low cost that prevents flow of air into an ink tank and prevents writing failure while allowing for productivity. A writing implement refill (10) comprises: an ink tank (20) composed of films (21) storing ink; a joint (30) connected to a tip of the ink tank (20); and a writing tip (40) connected to a tip of the joint (30). An inner circumferential surface of the tip of the ink tank (20) covers an outer circumferential surface of a rear end of the joint (30). A covering member (50) of a ring shape covers from outside an area where the tip of the ink tank (20) covers the outer circumferential surface of the rear end of the joint (30).