| 摘要 |
PROBLEM TO BE SOLVED: To prevent an increase in viscosity of ink and drying of the ink caused by evaporation of water in the ink from a clearance of a tip end of a chip when coated resin which is heated and molten is attached on the tip end of the chip and heat of the coated resin is transferred into the chip, and suppress writing blurring caused by intrusion of air into the chip occurring when a pressure increases in a seal member by fitting operation by the seal member.SOLUTION: A heat-shrinkable cylindrical member with one end closed is coated on a ballpoint pen body so as to cover at least a tip end of a ballpoint pen chip. Then, the heat-shrinkable cylindrical member is circumferentially attached tightly on the ballpoint pen body by heating and contracting an inner diameter. |
