Cosmetic brush and method for manufacturing same
AssigneeSinwa Corporation
InventorsHironori ASO, Keigo KOYANAGI
Life of this patent
Estimating the term…
Abstract
Provided is a cosmetic brush having bristles that easily go between thin eyelashes and easily catch eyelashes when rolling up, and a manufacturing method of the same. A cosmetic brush includes an applying portion formed into a substantially columnar shape as a whole in which bristles are spread radially from a core wire portion evenly in a circumferential direction of the core wire portion and continued in a helicoidal fashion in an axial direction of the core wire portion, and tip ends of the bristles are uniformly bent at substantially the same angle forward or rearward in the axial direction of the core wire portion, and tapered toward tip ends.
Claims9
1-6. (canceled)
A manufacturing method of a cosmetic brush, comprising:
- a forming step of forming a cosmetic brush before main machining including a straight core wire portion formed of a pair of core wires and a substantially columnar applying portion having bristles spread radially from twisted portions of the core wires and continued in a helicoidal fashion by pinching a number of bristles with predetermined lengths arranged in parallel in the form of a belt by the pair of metal core wires and helically twisting the core wires;
- a trimming step of forming an external shape of the applying portion by trimming tip ends of the bristles constituting the applying portion;
- and
- a grinding step of machining tip end portions of the bristles constituting the applying portion into predetermined shapes by grinding the tip end portions, wherein
- in the grinding step,
- the cosmetic brush before main machining is held on a flat grinding surface of a disk-shaped grind stone so that the core wire portion of the cosmetic brush before main machining is orthogonal to a radial direction of the grind stone, and
- while the cosmetic brush before main machining is rotated around its central axis, a side surface of the applying portion of the cosmetic brush before main machining is relatively pressed against a grinding surface of the rotating disk-shaped grind stone, whereby bending the tip end portions of the bristles while grinding them.
Dependencies are inferred from the claim text.