BALL FOR BALLPOINT PEN TIP

摘要

PROBLEM TO BE SOLVED: To provide a ball used for a tip end of a water-base ballpoint pen using a water-base ink capable of being retrained from corrosion as much as possible. SOLUTION: The ball used for a tip of the ballpoint pen using the water-base ink comprises a cemented carbide containing vanadium of 0.02 to 0.20 wt.%.