BALL-POINT PEN AND LOW-VISCOSITY OILY INK THEREFOR

摘要

PURPOSE: To obtain a low-viscosity oily ink for ball-point pen causing no trans fer of its clot at the beginning of writing because of no blotting, direct flow and backflow phenomena, therefore capable of writing beautiful lines therewith and highly favorable in writing touch during writing, and to obtain a ball-point pen suitable for the ink. CONSTITUTION: This ink comprises a colorant, additive and a solvent contg. >=60wt.% of an organic solvent <=0.1mmHg (20 deg.C) in vapor pressure, being <=200mPa.s and >=300mPa.s in viscosity at shear rates of 400S<-1> and 5S<-1> , respectively. The other objective ball-point pen stands equipped, in an inkholder, with this ink and a refill made up by filling the rear end of the ink with a follower containing at least one kind of solvent selected from volatile organic solvents and nonvolatile ones, a gelling agent consisting of fine silica particles and a silane-based surface modifier.