ALEXANDRIA, Va., June 9 -- United States Patent no. 12,285,967, issued on April 29, was assigned to THE SAILOR PEN Co. LTD. (Hiroshima, Japan).
"Writing instrument and pen tip part" was invented by Yuichiro Nakadai (Hiroshima, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A writing instrument and a pen tip part include: a pen tip which includes a writing portion and has a directional specification for writing of the writing portion; a cylindrical inner cylinder which fixes the pen tip; a cylindrical outer cylinder into which the inner cylinder can be inserted and which includes a finger guide portion on an outer peripheral surface; and a fixture which fixes the outer cylinder to the inner cylinder."
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