Ballpoint pen

A ballpoint pen comprising a ballpoint pen refill, the ballpoint pen refill including an ink reservoir cylinder and a ballpoint pen tip, an inside of the ink reservoir cylinder being filled with an oil-based ballpoint pen ink composition, the ballpoint pen tip being attached to a distal end portion of the ink reservoir cylinder, wherein

• a tip main body of the ballpoint pen tip includes:
• a ball holding chamber that holds a ball in a manner of allowing the ball to rotate while causing a part of the ball to protrude from a tip distal end portion;
• a ball socket provided on a bottom wall of the ball holding chamber, the ball being placed on the ball socket, the ball socket having a circular-arc surface conforming to an outer shape of the ball;
• an ink distribution hole formed in a center of the bottom wall of the ball holding chamber;
• and
• a plurality of ink distribution channels radially extending from the ink distribution hole,
• the oil-based ballpoint pen ink composition has an ink viscosity with a range of 500 mPa·s to 15000 mPa·s inclusive at 20° C. and a shear rate of 500 sec-1,
• the ball has a ball diameter of 0.5 mm or less,
• a sealing surface with a circular-arc shape is formed on an inner wall of the tip distal end portion,
• the tip distal end portion includes
• a first swaged portion having an inclination angle with a range of 90 degrees to 100 degrees inclusive, and
• a second swaged portion provided closer to the distal end side of the ballpoint pen tip than the first swaged portion, the second swaged portion having an inclination angle with a range of 110 degrees to 130 degrees inclusive, and
• an angle of the bottom wall of the ball holding chamber is the same as the inclination angle of the second swaged portion.