Writing ball, method for manufacturing writing ball, and ballpoint pen with writing ball
AssigneeKABUSHIKI KAISHA PILOT CORPORATION (also trading as PILOT CORPORATION)
InventorKouichi TAKAYAMA
Life of this patent
Estimating the term…
Abstract
In order to provide a writing ball capable of suppressing wear of a ball seat of a ballpoint pen tip and obtaining stable ink outflow, a writing ball that is a sphere, the sphere comprising, at least: a first hard component containing a first metal; a second hard component containing a second metal; and a binding component, the writing ball comprising: a first outer surface from which the first hard component is exposed, the first outer surface being an outermost surface of the sphere; and a recess including, as a bottom surface, a second outer surface from which the second hard component is exposed, the second outer surface being recessed inward from the first outer surface, wherein the first outer surface includes a smooth surface is provided.
Claims12
A writing ball that is a sphere, the sphere comprising, at least:
- a first hard component containing a first metal;
- a second hard component containing a second metal;
- and
- a binding component,
- the writing ball comprising:
- a first outer surface from which the first hard component is exposed, the first outer surface being an outermost surface of the sphere;
- and
- a recess including, as a bottom surface, a second outer surface from which the second hard component is exposed, the second outer surface being recessed inward from the first outer surface,
- wherein the first outer surface includes a smooth surface.
A method for manufacturing a writing ball, the method comprising:
- a sphere forming step of forming a sphere including at least a first hard component containing a first metal, a second hard component containing a second metal, and a binding component;
- a surface treatment step of performing a surface treatment on the sphere that has been formed;
- and
- an etching step of etching the sphere subjected to the surface treatment using a solution that dissolves the second hard component but does not dissolve the first hard component.
Dependencies are inferred from the claim text.