Kabushiki Kaisha Pilot Corporation

Yusuke Sanada

Nobukazu Seri

Takumi Kajiwara

Takeshi Fujii

Yuji Kawarazaki

Hidenori Kudou

Tomoharu Oonishi

A ballpoint pen. In the ballpoint pen, an 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. A ball has a ball diameter of 0.5 mm or less. A tip distal end portion includes a first swaged portion and a second swaged portion. The first swaged portion has an inclination angle with a range of 90 degrees to 100 degrees inclusive. The second swaged portion is provided closer to a distal end side of a ballpoint pen tip than the first swaged portion and has an inclination angle with a range of 110 degrees to 130 degrees inclusive. An angle of a bottom wall of a ball holding chamber is the same as the inclination angle of the second swaged portion.

Ballpoint pen

A mechanical pencil has: a shaft tube; a ferrule unit supported by the shaft tube; a lead holding unit having a chuck configured to relatively move with respect to the ferrule unit to eject lead held by the same; and an indication body provided movably in an axial direction. The indication body delimits from rearward a lead storage space formed rearward the chuck in the shaft tube. The indication body located at least at a predetermined position is viewable from outside the shaft tube. A length along the axial direction between a rear end of the lead storage space and a front end of the ferrule unit, in a state where the indication body has moved most rearward along the axial direction, is equal to or more than twice a length of spare lead to be stored in the lead storage space.

Mechanical pencil

A pressurized writing implement includes a shaft tube capable of housing therein a refill filled with a writing implement ink composition. The pressurized writing implement further includes a pressurizing mechanism that applies a pressure to the writing implement ink composition, the pressurized writing implement being capable of switching a writing state in which a front end part of the refill projects from a front end opening of the shaft tube, and a not-writing state in which the front end part of the refill is retracted from the front end opening of the shaft tube. The pressurized writing implement further includes a pressurizing-force adjusting mechanism that adjusts the pressure.

Growing community of inventors

Tokyo-to, Japan

Yusuke Sanada