WRITING INSTRUMENT

摘要

A writing instrument having a pen point (1) and an ink holding tube (3) provided with the pen point (1) at one end thereof, wherein the pen point (1) has a structure in which a ball valve (6) energized by a spring (5) self-contained in a tip (4) with a spring strength of 10 to 40 g contacts closely with the inner periphery of a holding portion (7) located at the edge of the tip (4), and wherein the ink holding tube (3) is filled with an oily ink composition which has a viscosity at 20°C at 20 rpm of 10 to 50 mPa.s (ELD type viscometer, 1° 34' cone) and is a Newtonian fluid, and wherein the above oily ink composition comprises an organic solvent, an alcohol-soluble dye and a resin, and the above organic solvent comprises one or more organic solvents selected from the group of propylene glycol monomethyl ether, ethyl alcohol and propyl alcohol as a primary solvent.