JP7728628B2 - makeup brushes - Google Patents

Description

This disclosure relates to a cosmetic brush.

Manicure brushes used to remove nail polish from a container and apply it to nails are known to have a brush section made of resin bristles at the tip of a shaft fixedly held in a cylindrical grip. Prior art in this regard can be found, for example, in Patent Document 1.

Japanese Patent Application Publication No. 10-295440

However, despite their small size, conventional cosmetic brushes are made up of multiple components, making efficient manufacturing difficult and leaving room for improvement.

The present disclosure aims to solve these problems, and its purpose is to propose a cosmetic brush with a simplified structure.

The cosmetic brush of the present disclosure comprises:
A knob and
a shaft portion fixed to the knob portion;
A cosmetic brush comprising: a brush portion provided at the tip of the shaft portion,
The shaft portion and the brush portion are integrally molded,
the shaft portion has a flat shape in which the vertical and horizontal dimensions of a cross section perpendicular to the central axis are different,
the shaft portion has a protrusion that protrudes in a short direction of the flat shape,
The side surface of the convex portion has an inclined surface that slopes toward the central axis direction toward the longitudinal center position of the flat shape, and the convex portion is not located at the longitudinal center position of the flat shape.

Furthermore, in the cosmetic brush of the present disclosure, in the above configuration, it is preferable that the grip portion, shaft portion, and brush portion are integrally molded.

This disclosure makes it possible to propose a cosmetic brush with a simplified structure.

FIG. 1A is a front (vertical) half-sectional view, and FIG. 1B is a side (horizontal) half-sectional view of a cosmetic brush according to a first embodiment of the present disclosure. 1 is a diagram showing a cosmetic brush according to a first embodiment of the present disclosure as viewed from the tip side. 1 is a diagram showing a state in which a cap member is attached to a cosmetic brush according to a first embodiment of the present disclosure and the cosmetic brush is placed in a cosmetic container. 1A is a front half-sectional view of a cosmetic brush according to a second embodiment of the present disclosure, and FIG. 1B is a side half-sectional view of the cosmetic brush according to the second embodiment of the present disclosure. 10A and 10B are a front half-sectional view and a side half-sectional view, respectively, of a cosmetic brush according to a third embodiment of the present disclosure. 10A and 10B are a front half-sectional view and a side half-sectional view, respectively, of a cosmetic brush according to a fourth embodiment of the present disclosure. 10A and 10B are a front half-sectional view and a side half-sectional view, respectively, of a cosmetic brush according to a fifth embodiment of the present disclosure. 10A and 10B are diagrams illustrating deformation of a cosmetic brush according to a fifth embodiment of the present disclosure when (a) a bending moment is applied from the lateral direction and (b) a bending moment is applied from the vertical direction. 10A and 10B are a front half-sectional view and a side half-sectional view, respectively, of a cosmetic brush according to a sixth embodiment of the present disclosure. 13A and 13B are diagrams illustrating deformation of a cosmetic brush according to a sixth embodiment of the present disclosure when (a) a bending moment is applied from the lateral direction and (b) a bending moment is applied from the vertical direction.

The present disclosure will be explained in more detail below with reference to the drawings.

The cosmetic brush 100 according to the first embodiment of the present disclosure will be described in detail with reference to Figures 1 to 3. In this specification, claims, abstract, and drawings, the side on which the gripping portion 1 is located will be referred to as the base end side (the upper side in Figures 1(a) and 1(b)), and the side on which the brush portion 3 is located will be referred to as the tip end side (the lower side in Figures 1(a) and 1(b)).

The radially outward direction refers to the direction away from the central axis O along a straight line that passes through the central axis O of the cosmetic brush 100 and is perpendicular to the central axis O, which extends in the vertical direction in Figures 1(a) and 1(b), and the radially inward direction refers to the direction toward the central axis O along that straight line. The circumferential direction refers to the direction of rotation around the central axis O.

Figure 1(a) is a front half-sectional view of the cosmetic brush 100 according to this embodiment, and Figure 1(b) is a side half-sectional view of the cosmetic brush 100. Here, the direction perpendicular to the plane of the paper in Figure 1(a) (the left-right direction in Figure 1(b)) is defined as the vertical direction, and the direction perpendicular to the plane of the paper in Figure 1(b) (the left-right direction in Figure 1(a)) is defined as the horizontal direction. These vertical and horizontal directions correspond to the vertical and horizontal directions in a cross section perpendicular to the central axis O of the cosmetic brush 100 in the claims.

Figures 1 to 3 show the shape of the cosmetic brush 100 immediately after it has been formed by resin molding and before it has cooled.

As shown in Figures 1(a) and 1(b), the cosmetic brush 100 according to this embodiment comprises a substantially cylindrical gripping portion 1 that is held by the user when using the cosmetic brush 100, a flat plate-shaped shaft portion 2 fixed to the tip of the gripping portion 1, and a brush portion 3 attached to the tip of the shaft portion 2 for applying cosmetics. The cosmetic brush 100 according to this embodiment can be used, for example, as a nail polish brush that is soaked in nail polish and used to apply it to nails.

The grip portion 1 has a generally cylindrical shape and is provided with an axial rib 1a extending along the central axis O and projecting radially outward from the outer circumferential surface. In this embodiment, the axial ribs 1a are formed at four equally spaced locations around the circumference. An annular protrusion 1b is also formed on the outer circumferential surface near the tip of the grip portion 1. The user may use the cosmetic brush 100 by directly holding the grip portion 1, or the grip portion 1 may be secured to the inside of a cap member 20 (see FIG. 3) that is attached to the opening 11 of the cosmetic container 10. When securing the grip portion 1 to the cap member 20, the annular protrusion 1b may be undercut-engaged with the engaging protrusion 21c of the cap member 20, and the axial rib 1a may be engaged with the anti-rotation rib 21b of the cap member 20 to prevent rotation of the cap member 20 relative to the grip portion 1. By engaging and fixing the cap member 20 to the mouth 11 of the cosmetic container 10, the cosmetic container 10 is closed and the brush portion 3 extending from the cap member 20 into the interior of the cosmetic container 10 can be immersed in the cosmetic.

The knob 1 may also function as a cap member that closes the cosmetic container 10.

A flat plate-shaped shaft portion 2 is fixed to the tip of the knob portion 1.

As shown in Figures 1(a) and 1(b), the shaft portion 2 is a flattened plate-like member in which the horizontal dimension of a cross section perpendicular to the central axis O is greater than the vertical dimension, and it is fixed to the grip portion 1 via a tapered portion 2t that tapers toward the tip. This configuration allows the shaft portion 2 to be easily bent in the short direction of its flat shape (left-right direction in Figure 1(b)) when a bending moment acts on the shaft portion 2 when the brush portion 3 (described below) is soaked in cosmetics and used. Therefore, when a user wishes to apply cosmetics while tilting the brush portion 3 relative to the grip portion 1, they simply rotate the cosmetic brush 100 around the central axis O so that the direction in which they want to tilt the brush portion 3 is the short direction of the flat shape of the shaft portion 2, and then use the cosmetic brush.

In this embodiment, as shown in Figures 1(a) and 1(b), the shaft portion 2 is provided with protrusions 2a that protrude in the vertical direction (the short side direction of the flat shape). The protrusions 2a protrude on both sides of the shaft portion 2 in the vertical direction (the short side direction of the flat shape), and are arranged in alternating rows along the central axis O, with areas where three protrusions 2a are lined up and areas where two protrusions 2a are lined up in the horizontal direction (the long direction of the flat shape).

By providing the convex portions 2a on both longitudinal sides of the shaft portion 2 as described above, when the cap member 20 is removed from the cosmetic container 10 while the lower portion of the shaft portion 2 is immersed in the cosmetic as shown in Figure 3, the cosmetic adhering to the shaft portion 2 is retained on the surface of the convex portions 2a and in the areas between the convex portions 2a, allowing the user to continue using the cosmetic without having to repeatedly reapply the cosmetic to the brush portion 3.

The spacing and height of the protrusions 2a can be determined as desired depending on the viscosity of the cosmetic used. For example, if the cosmetic has a high viscosity, the spacing between the protrusions 2a should be widened to allow more of the cosmetic to be held between them. If the cosmetic has a low viscosity, the spacing between the protrusions 2a should be narrowed to allow the cosmetic to be more easily held between them.

Furthermore, the shape of the protrusions 2a when viewed vertically is not limited to a circular shape. The shape of the protrusions 2a when viewed vertically may be an oval or rectangular shape, and the sizes of the protrusions 2a may vary.

In this embodiment, the protrusions 2a are configured to be approximately the same height, but this is not limited to this. For example, the height of the protrusions 2a may be relatively higher at the tip end, which is more likely to be soaked in cosmetics. Also, in this embodiment, the protrusions 2a are configured to be spaced at equal intervals along the central axis O, but this is not limited to this. They may be provided only at the tip end, which is more likely to be soaked in cosmetics, or more protrusions 2a may be provided at the tip end. Furthermore, in order to efficiently utilize the cosmetics held on the protrusions 2a in the brush part 3, the fixing part 3b that fixes the resin bristles 3a may be provided with communication holes through which cosmetics can pass.

As shown in Figures 1(a) and 1(b), a brush part 3 for applying cosmetics is fixed to the tip of the shaft part 2.

The brush part 3 has a disk-shaped fixed part 3b attached to the tip of the shaft part 2 and multiple resin bristles 3a extending further from the fixed part 3b toward the tip.

As shown in Figures 1(a), 1(b), and 2, the fixed portion 3b has a disk shape that is symmetrical about the central axis O and is thickened in the direction of the central axis O at the lateral center. More specifically, the distal side surface of the fixed portion 3b is substantially flat, while the proximal side surface of the fixed portion 3b is inclined toward the proximal end toward the lateral center, and includes a thickened portion 3b1 in the lateral center that is thickened in the direction of the central axis O.

As described above, by providing the fixed portion 3b with the thickened portion 3b1 at the lateral center, during the cooling process after injection molding of the cosmetic brush 100, the fixed portion 3b shrinks more in the direction of the central axis O at the lateral center where the thickened portion 3b1 is located than at the lateral edge portions, and therefore the tip side surface of the fixed portion 3b is displaced slightly toward the base end at the lateral center compared to the lateral edge portions. This deformation of the fixed portion 3b during cooling causes the tips of the resin bristles 3a fixed to the tip side surface of the fixed portion 3b to be oriented radially inward.

As shown in Figure 2, the resin bristles 3a include outer bristles 3a1 arranged in a ring shape around the central axis O, and inner bristles 3a2 arranged concentrically with the outer bristles 3a1, radially inward of the outer bristles 3a1. In this embodiment, each resin bristles 3a has a generally triangular shape when viewed from the tip, and is configured so that its circumferential width increases radially outward. With this configuration, a surface with a wide circumferential width and few irregularities is positioned radially outward as the application surface, making it easier to apply cosmetics that have been soaked into each resin bristles 3a using the application surface.

In this embodiment, the resin bristles 3a are arranged in a circular ring shape as shown in FIG. 2. By configuring the resin bristles 3a so that their circumferential width narrows radially inward, as shown in FIG. 2, it is possible to arrange a larger number of resin bristles 3a at a higher density within a brush portion 3 of a given diameter. Furthermore, by arranging the resin bristles 3a at a higher density, it is possible to prevent the cosmetic from dripping between the resin bristles 3a soaked in the cosmetic. The spacing between adjacent resin bristles 3a can be determined as desired depending on the viscosity of the cosmetic. That is, when using a cosmetic with a high viscosity, it is sufficient to increase the spacing between the resin bristles 3a to allow the cosmetic to easily enter between the resin bristles 3a. When using a cosmetic with a low viscosity, it is preferable to decrease the spacing between the resin bristles 3a to prevent the cosmetic from dripping between the resin bristles 3a.

In this embodiment, as shown in Figures 1(a) and 1(b), the resin bristles 3a extend along the central axis O, and the radially outer end of each resin bristles 3a extends approximately parallel to the central axis O, while the radially inner end is formed so as to gradually approach the radially outer end from the radially thick base end to the radially thin tip end. As a result, the longitudinal length from the base end to the tip end at the radially inner end of each resin bristles 3a is longer than the longitudinal length from the base end to the tip end at the radially outer end.

With this configuration, after the cosmetic brush 100 is molded and cooled, the relatively longer radially inner end of each resin bristles 3a shrinks more due to cooling than the radially outer end. Therefore, the tip of each resin bristles 3a is displaced radially inward due to cooling after molding.

By displacing the tip of each resin bristles 3a radially inward, the cosmetics that have fallen between the resin bristles 3a are more easily retained, effectively preventing the cosmetics from dripping. Furthermore, because the tip of the brush portion 3 is compact, it is possible to easily return the brush portion 3 to the cosmetic container 10 through the opening 11 without compromising its aesthetic appearance.

In this embodiment, the handle portion 1, shaft portion 2, and brush portion 3 are integrally molded from synthetic resin by injection molding or the like. Low-density polyethylene resin is used as the synthetic resin that makes up the cosmetic brush 100. However, this is not limited to this embodiment, and various thermoplastic resins other than low-density polyethylene can be used, such as high-density polyethylene, medium-density polyethylene, polypropylene resin (PP), polyvinyl chloride resin (PVC), nylon resin, polyethylene terephthalate resin (PET), or polybutylene terephthalate resin (PBT). The handle portion 1 does not necessarily have to be integrally molded with the shaft portion 2 and brush portion 3; it may be formed separately from the shaft portion 2 and brush portion 3 and then attached to the shaft portion 2 and brush portion 3.

In this embodiment, it is assumed that the handle portion 1 through the brush portion 3 are formed in a single injection molding process, but this is not limited to this. For example, only the handle portion 1, only the shaft portion 2, or both the handle portion 1 and the shaft portion 2 may be prepared in advance and used as an insert material to insert-molde the cosmetic brush 100. When using insert molding, the material of the brush portion 3 may be different from that of the handle portion 1 and the shaft portion 2. In this disclosure, the cooling process of the brush portion 3 is used to shape the tips of the resin bristles 3a, so when using insert molding, it is preferable to mold the brush portion 3 as the final process.

During the cooling process of the injection-molded cosmetic brush 100, the radially inner ends of each resin bristles 3a and the lateral center of the fixing portion 3b, which were formed at a higher temperature, are cooled to the same temperature as the other parts, and therefore experience a greater temperature drop and accompanying greater shrinkage than the other parts. This allows the tips of each resin bristles 3a to be more reliably displaced radially inward during cooling.

The cosmetic brush 100 according to this embodiment can be used with the cap member 20 and cosmetic container 10 shown in Figure 3. In Figure 3, the cosmetic brush 100 has the knob portion 1 fixed to the inside of the cap member 20, and the cap member 20 is attached to the mouth portion 11 of the cosmetic container 10, so that the brush portion 3 is immersed in the cosmetic in the cosmetic container 10.

The cap member 20 comprises a peripheral wall 21 and a top wall 22 connected to the upper end of the peripheral wall 21. The lower inner surface of the peripheral wall 21 is provided with a female threaded portion 21a that threadably engages with the male threaded portion 11a of the mouth 11 of the cosmetic container 10. Also provided above the female threaded portion 21a are an engagement protrusion 21c that undercuts and engages with the annular protrusion 1b of the knob 1, and an anti-rotation rib 21b that engages with the axial rib 1a of the knob 1 to prevent rotation of the cap member 20 relative to the knob 1.

The cosmetic container 10 comprises a cylindrical body 13 that forms a storage space S for the cosmetic, a mouth 11 that is connected to the upper part of the body 13 via a shoulder 12 and to which a cap member 20 is attached, and a bottom 14 that closes the lower end of the body 13.

By threading the female thread portion 21a of the cap member 20 into the male thread portion 11a of the mouth 11 of the cosmetic container 10, the lower end of the knob 1 abuts the upper end of the mouth 11 and the reduced diameter portion 2t of the shaft 2 abuts the inner surface of the mouth 11, thereby sealing the mouth 11 liquid-tight. At this time, the tip of the shaft 2 and the brush portion 3, which hang down from the knob 1 into the storage space S of the cosmetic container 10, are immersed in the cosmetic, allowing the cosmetic to seep into the gaps between the resin bristles 3a and the areas between the protruding portions 2a of the shaft 2.

When using the cosmetic, the cap member 20 is turned counterclockwise in a plan view relative to the cosmetic container 10 to release the threaded engagement between the cap member 20 and the mouth portion 11. After releasing the threaded engagement, the cap member 20 can be pulled upward from the mouth portion 11 to remove the brush portion 3 soaked in the cosmetic from the container.

The user applies cosmetics to the area to be made up by bringing the resin bristles 3a of the brush portion 3 into contact with the area to be made up and then moving the cosmetic brush 100, for example, left and right as shown in Figure 1B. At this time, the bending moment generated by the force acting between the brush portion 3 and the area to be made up causes the shaft portion 2 to bend and deform within the plane of Figure 1(b), allowing the brush portion 3 to apply cosmetics in an optimal position.

As described above, this embodiment is a cosmetic brush 100 comprising a handle 1, a shaft 2 fixed to the handle 1, and a brush portion 3 attached to the tip of the shaft 2. The shaft 2 and brush portion 3 are integrally molded, and the shaft 2 is configured to have a flattened shape with different vertical and horizontal dimensions in a cross section perpendicular to the central axis O. By adopting this configuration, it is possible to realize a cosmetic brush 100 with a simplified structure by integrating the shaft 2 and brush portion 3. Furthermore, because the shaft 2 can bend and deform relatively freely in the horizontal direction due to the bending moment generated by the force applied between the brush portion 3 and the area to be made up, the brush portion 3 can be easily maintained in an optimal position to apply cosmetics.

In addition, in this embodiment, the shaft portion 2 is configured to have a flattened protrusion 2a that protrudes in the short direction. By adopting this configuration, when the tip of the shaft portion 2 and the brush portion 3 are immersed in the cosmetic in the storage space S of the cosmetic container 10 through the handle 1, the cosmetic can penetrate the surfaces of the protrusions 2a and the areas between the protrusions 2a, allowing the user to continue using the product without having to repeatedly reapply the cosmetic to the brush portion 3.

Furthermore, in this embodiment, the grip portion 1, shaft portion 2, and brush portion 3 are configured to be integrally molded. By adopting this configuration, it is possible to realize a cosmetic brush 100 with an even simpler structure by integrating the grip portion 1, shaft portion 2, and brush portion 3.

Next, a cosmetic brush 200 according to a second embodiment of the present disclosure will be described using Figures 4(a) and 4(b). This embodiment has a similar configuration to the first embodiment, except for the shape of the shaft 2, which is different from the first embodiment. Therefore, the following description will focus on the differences from the first embodiment. Figures 4(a) and 4(b) show the shape of the cosmetic brush 200 immediately after it has been formed by resin molding and before it has cooled.

As shown in Figures 4(a) and 4(b), the cosmetic brush 200 according to this embodiment comprises a generally cylindrical gripping portion 1 that is held by the user when using the cosmetic brush 200, a flat plate-shaped shaft portion 2 fixed to the tip of the gripping portion 1, and a brush portion 3 attached to the tip of the shaft portion 2 for applying cosmetics. The cosmetic brush 200 according to this embodiment can also be used, for example, as a nail polish brush that is soaked in nail polish and applied to nails. The same applies to the third to sixth embodiments described below.

The knob 1 has a generally cylindrical shape, with axial ribs 1a extending along the central axis O and protruding radially outward from the outer circumferential surface. In this embodiment, the axial ribs 1a are formed at four equally spaced locations around the circumference. Additionally, an annular protrusion 1b is formed on the outer circumferential surface near the tip of the knob 1.

A flat plate-shaped shaft portion 2 is fixed to the tip of the knob portion 1.

As shown in Figures 4(a) and 4(b), the shaft portion 2 is a flattened plate-like member in which the horizontal dimension of a cross section perpendicular to the central axis O is greater than the vertical dimension, and it is fixed to the grip portion 1 via a tapered portion 2t that tapers toward the tip. This configuration allows the shaft portion 2 to be easily bent in the short direction of its flat shape (left-right direction in Figure 4(b)) when a bending moment acts on the shaft portion 2 when the brush portion 3 (described below) is soaked in cosmetics and used. Therefore, when a user wishes to apply cosmetics while tilting the brush portion 3 relative to the grip portion 1, they simply determine the circumferential position of the cosmetic brush 200 around the central axis O so that the direction in which they want to tilt the brush portion 3 is the short direction of the flat shape of the shaft portion 2 before use.

In this embodiment, as shown in Figures 4(a) and 4(b), the shaft portion 2 has recesses 2b recessed in the vertical direction (the short direction of the flat shape). The recesses 2b are recessed inward from both sides of the shaft portion 2 in the vertical direction (the short direction of the flat shape), and areas where three recesses 2b are lined up in the horizontal direction (the long direction of the flat shape) and areas where two recesses 2b are lined up in the horizontal direction (the long direction of the flat shape) are alternately arranged in the direction of the central axis O. As shown in Figure 4(b), three recesses 2b lined up in the horizontal direction are formed as through holes 2b1. Furthermore, two recesses 2b lined up in the horizontal direction are formed as bottomed holes 2b2.

By providing recesses 2b on both longitudinal sides of the shaft 2 as described above, when the cap member 20 is removed from the cosmetic container 10 while the tip of the shaft 2 is immersed in the cosmetic, as shown in Figure 3, the cosmetic adhering to the shaft 2 is retained within the recesses 2b, allowing the user to continue using the cosmetic without having to repeatedly reapply the cosmetic to the brush part 3.

The diameter and depth of the recesses 2b can be determined as desired depending on the viscosity of the cosmetic used, etc. For example, if the viscosity of the cosmetic is high, the diameter of the recesses 2b should be increased to allow more of the cosmetic to be retained therein, and if the viscosity of the cosmetic is low, the diameter of the recesses 2b should be decreased to make it easier for the cosmetic to be retained therein. Also, if the viscosity of the cosmetic is high, the depth of the recesses 2b should be decreased to make it easier for the cosmetic to enter the recesses 2b, and if the viscosity of the cosmetic is low, the depth of the recesses 2b should be increased to allow more of the cosmetic to be retained therein.

Furthermore, the shape of the recesses 2b when viewed vertically is not limited to a circular shape. The shape of the recesses 2b when viewed vertically may be an oval or rectangular shape, and the sizes of each recess 2b may be different.

In this embodiment, the recesses 2b are arranged at equal intervals along the central axis O, but this is not limited to this configuration. They may be arranged only on the tip side, which is more easily soaked in cosmetics, or more recesses 2b may be arranged on the tip side.

In this embodiment, the through holes 2b1 and the blind holes 2b2 are arranged alternately in the direction of the central axis O, but this is not limited to this configuration. Depending on the flexibility and cosmetic retention capacity required of the shaft portion 2, the recess 2b may consist of only through holes 2b1 or only blind holes 2b2. The ratio of through holes 2b1 to blind holes 2b2 may also be changed.

Furthermore, to enable the cosmetics held in the recess 2b to be efficiently utilized in the brush part 3, the fixing part 3b that fixes the resin bristles 3a may be provided with a communication hole through which the cosmetics can pass.

As shown in Figures 4(a) and 4(b), a brush part 3 for applying cosmetics is fixed to the tip of the shaft part 2.

The brush part 3 has a disk-shaped fixed part 3b attached to the tip of the shaft part 2 and multiple resin bristles 3a extending further from the fixed part 3b toward the tip.

As shown in Figures 4(a) and 4(b), the fixed portion 3b has a disk shape that is symmetrical about the central axis O and is thickened in the direction of the central axis O at the longitudinal center. More specifically, the distal side surface of the fixed portion 3b is substantially flat, while the proximal side surface of the fixed portion 3b is inclined toward the proximal end toward the longitudinal center, forming a thick portion 3b1 at the longitudinal center that is thickened in the direction of the central axis O.

As described above, by providing the thick portion 3b1 at the longitudinal center of the fixed portion 3b, the tips of each resin bristles 3a fixed to the tip side of the fixed portion 3b are oriented radially inward during cooling, similar to the first embodiment.

As described above, in this embodiment, the shaft portion 2 is configured to have a flattened recess 2b that is recessed in the short direction. By adopting this configuration, when the tip of the shaft portion 2 and the brush portion 3 are immersed in the cosmetics in the storage space S of the cosmetic container 10, the cosmetics can enter the interior of the recess 2b, allowing the user to continue using the cosmetic container 10 without having to repeatedly reapply cosmetics to the brush portion 3.

Next, a cosmetic brush 300 according to a third embodiment of the present disclosure will be described using Figures 5(a) and 5(b). This embodiment has a similar configuration to the first and second embodiments, except for the shape of the shaft portion 2, which is different from the first and second embodiments. Therefore, the following description will focus on the differences from the first and second embodiments. Figures 5(a) and 5(b) show the shape of the cosmetic brush 300 immediately after it has been formed by resin molding and before it has cooled.

As shown in Figures 5(a) and 5(b), the cosmetic brush 300 according to this embodiment comprises a generally cylindrical gripping portion 1 that is held by the user when using the cosmetic brush 300, a flat plate-shaped shaft portion 2 fixed to the tip of the gripping portion 1, and a brush portion 3 attached to the tip of the shaft portion 2 for applying cosmetics.

The knob 1 has a roughly cylindrical shape, and a flat, plate-shaped shaft 2 is fixed to the tip of the knob 1.

As shown in Figures 5(a) and 5(b), the shaft portion 2 is a flattened plate-like member in which the horizontal dimension of a cross section perpendicular to the central axis O is greater than the vertical dimension. The shaft portion 2 is fixed to the grip portion 1 via a tapered portion 2t, which tapers toward the tip. This configuration allows the shaft portion 2 to be easily bent in the short direction of its flattened shape (the left-right direction in Figure 5(b)) when a bending moment acts on the shaft portion 2 when the brush portion 3 (described below) is soaked in cosmetics and used. Therefore, when a user wishes to apply cosmetics while tilting the brush portion 3 relative to the grip portion 1, they simply determine the circumferential position of the cosmetic brush 300 around the central axis O so that the desired tilt direction of the brush portion 3 is the short direction of the flattened shape of the shaft portion 2 before use.

In this embodiment, as shown in Figures 5(a) and 5(b), the shaft portion 2 is provided with convex portions 2c that protrude in the vertical direction (the short direction of the flat shape). The convex portions 2c protrude on both sides of the shaft portion 2 in the vertical direction (the short direction of the flat shape) and have the shape of a parallelogram when viewed from the vertical direction. Two convex portions 2c are arranged side by side in the horizontal direction (the long direction of the flat shape) and are arranged symmetrically with respect to the central axis O. Furthermore, multiple convex portions 2c are arranged at equal intervals along the central axis O.

As described above, the convex portion 2c has a parallelogram shape when viewed from the vertical direction, and one pair of side surfaces forms an inclined surface 2c1 that slopes toward the center of the longitudinal direction of the flattened shape in the direction of the central axis O.

By providing the convex portions 2c on both longitudinal sides of the shaft portion 2 as described above, when the cap member 20 is removed from the cosmetic container 10 while the lower portion of the shaft portion 2 is immersed in the cosmetic as shown in Figure 3, the cosmetic adhering to the shaft portion 2 is retained on the surface of the convex portions 2c and in the areas between the convex portions 2c, allowing the user to continue using the cosmetic without having to repeatedly reapply the cosmetic to the brush portion 3.

In this embodiment, one pair of side surfaces of the convex portion 2c forms an inclined surface 2c1 that slopes toward the center of the longitudinal direction of the flattened shape toward the central axis O. This allows cosmetics held on the surface of the convex portion 2c to easily flow through the area between the inclined surfaces 2c1 and into the brush portion 3. This allows cosmetics held on the surface of the convex portion 2c to be easily and continuously used.

The spacing and height of the protrusions 2c can be determined as desired depending on the viscosity of the cosmetic used. For example, if the cosmetic has a high viscosity, the spacing between the protrusions 2c should be widened to allow more of the cosmetic to be held between them. If the cosmetic has a low viscosity, the spacing between the protrusions 2c should be narrowed to allow the cosmetic to be more easily held between them.

In this embodiment, the protrusions 2c are configured to be approximately the same height, but this is not limited to this. For example, the height of the protrusions 2c may be relatively higher at the tip end, which is more likely to be soaked in cosmetics. Also, in this embodiment, the protrusions 2c are configured to be spaced at equal intervals along the central axis O, but this is not limited to this. They may be provided only at the tip end, which is more likely to be soaked in cosmetics, or more protrusions 2c may be provided at the tip end. Furthermore, in order to efficiently utilize the cosmetics held on the protrusions 2c in the brush part 3, the fixing part 3b, which fixes the resin bristles 3a, may be provided with communication holes through which cosmetics can pass.

As shown in Figures 5(a) and 5(b), a brush part 3 for applying cosmetics is fixed to the tip of the shaft part 2.

The brush part 3 has a disk-shaped fixed part 3b attached to the tip of the shaft part 2 and multiple resin bristles 3a extending further from the fixed part 3b toward the tip.

As shown in Figures 5(a) and 5(b), the fixed portion 3b has a disk shape that is symmetrical about the central axis O and is thickened in the direction of the central axis O at the vertical center. More specifically, the tip side surface of the fixed portion 3b is substantially flat, while the base side surface of the fixed portion 3b is inclined toward the base end toward the horizontal center, and includes a thick portion 3b1 at the vertical center that is thickened in the direction of the central axis O.

As described above, by providing the fixed portion 3b with a thick portion 3b1 in the vertical center position, the tips of each resin bristles 3a fixed to the tip side surface of the fixed portion 3b are oriented radially inward, as in the first and second embodiments.

As described above, in this embodiment, the side of the convex portion 2c is configured to have an inclined surface 2c1 that slopes toward the center of the longitudinal direction of the flattened shape in the direction of the central axis O. By adopting this configuration, when the tip of the shaft portion 2 and the brush portion 3 are immersed in the cosmetic in the storage space S of the cosmetic container 10, the cosmetic can be held around the convex portion 2c, and the held cosmetic can be guided to the brush portion 3 through the inclined surface 2c1. This allows the user to continue using the cosmetic efficiently.

Next, a cosmetic brush 400 according to a fourth embodiment of the present disclosure will be described using Figures 6(a) and 6(b). This embodiment has a similar configuration to the first to third embodiments, except for the shape of the shaft portion 2, which is different from the first to third embodiments. Therefore, the following description will focus on the differences from the first to third embodiments. Figures 6(a) and 6(b) show the shape of the cosmetic brush 400 immediately after it has been formed by resin molding and before it has cooled.

As shown in Figures 6(a) and 6(b), the cosmetic brush 400 according to this embodiment comprises a substantially cylindrical gripping portion 1 that is held by the user when using the cosmetic brush 400, a flattened shaft portion 2 fixed to the tip of the gripping portion 1, and a brush portion 3 attached to the tip of the shaft portion 2 for applying cosmetics.

The knob 1 has a roughly cylindrical shape, and a flattened shaft 2 is fixed to the tip of the knob 1.

As shown in Figures 6(a) and 6(b), the stem 2 is a flattened plate-like member in which the horizontal dimension of a cross section perpendicular to the central axis O is greater than the vertical dimension, and is fixed to the knob 1 via a tapered portion 2t that tapers toward the tip. In this embodiment, unlike the first to third embodiments, the stem 2 has a sinusoidal wave-like undulation 2d in the short direction of the flattened shape toward the central axis O (see Figure 6(b)).

With this configuration, when the brush portion 3 (described below) is soaked in cosmetics and used, a bending moment acts on the shaft portion 2, which can easily bend and deform in the short direction of the flattened shape (left and right in FIG. 6(b)) while changing the curvature of the wavy shape shown in FIG. 6(b). Therefore, if a user wishes to apply cosmetics while tilting the brush portion 3 relative to the grip portion 1, they can simply determine the circumferential position of the cosmetic brush 400 around the central axis O so that the direction in which they want to tilt the brush portion 3 is the short direction of the flattened shape of the shaft portion 2 before use.

In this embodiment, as shown in Figures 6(a) and 6(b), the shaft portion 2 has a sinusoidal wave-like corrugation 2d in the vertical direction (the short direction of the flattened shape).

By providing the wavy pattern 2d on the shaft 2 as described above, when the cap member 20 is removed from the cosmetic container 10 while the lower part of the shaft 2 is immersed in the cosmetic as shown in Figure 3, the cosmetic adhering to the sinusoidal wavy pattern 2d of the shaft 2 is retained in the peaks and valleys of the wavy pattern 2d. This allows the user to continue using the cosmetic sequentially supplied to the brush portion 3 from the wavy pattern 2d without having to repeatedly reapply the cosmetic to the brush portion 3.

The spacing between the peaks of the wavy shape 2d in the direction of the central axis O and the height of the flat shape in the short direction can be determined as desired depending on the viscosity of the cosmetic used. For example, if the viscosity of the cosmetic is high, the spacing between the peaks should be widened so that more of the cosmetic is held in the peaks and valleys of the wavy shape 2d. If the viscosity of the cosmetic is low, the spacing between the peaks should be narrowed so that the cosmetic is more easily held in the peaks and valleys.

In this embodiment, the peaks and valleys are configured to have approximately the same shape along the central axis O, but this is not limited to this. For example, the height of the peaks and valleys may be relatively higher at the tip end, which is more likely to be soaked in cosmetics. In addition, in this embodiment, the peaks and valleys are configured to be spaced at equal intervals along the central axis O, but this is not limited to this. They may be located only at the tip end, which is more likely to be soaked in cosmetics, or more peaks and valleys may be located at the tip end. In addition, to enable the cosmetics held in the wavy shape 2d to be efficiently utilized in the brush part 3, the fixing part 3b that fixes the resin bristles 3a may be provided with communication holes through which the cosmetics can pass.

As shown in Figures 6(a) and 6(b), a brush part 3 for applying cosmetics is fixed to the tip of the shaft part 2.

The brush part 3 has a disk-shaped fixed part 3b attached to the tip of the shaft part 2 and multiple resin bristles 3a extending further from the fixed part 3b toward the tip.

As described above, in this embodiment, the shaft portion 2 is configured to have a wavy shape 2d that wavy in the short direction of the flat shape toward the central axis O. By adopting this configuration, when the tip of the shaft portion 2 and the brush portion 3 are immersed in the cosmetic in the storage space S of the cosmetic container 10, the cosmetic can be held in the peaks and valleys of the wavy shape 2d, and the held cosmetic can be guided to the brush portion 3 along the wavy shape 2d. This allows the user to continue using the cosmetic efficiently.

Next, a cosmetic brush 500 according to a fifth embodiment of the present disclosure will be described using Figures 7(a), 7(b), 8(a), and 8(b). This embodiment has a similar configuration to the first to fourth embodiments, except for the shape of the shaft portion 2, which is different from the first to fourth embodiments. Therefore, the following description will focus on the differences from the first to fourth embodiments. Figures 7(a) and 7(b) show the shape of the cosmetic brush 500 immediately after it has been formed by resin molding and before it has cooled.

As shown in Figures 7(a) and 7(b), the cosmetic brush 500 according to this embodiment comprises a substantially cylindrical gripping portion 1 that is held by the user when using the cosmetic brush 500, a flattened shaft portion 2 fixed to the tip of the gripping portion 1, and a brush portion 3 attached to the tip of the shaft portion 2 for applying cosmetics.

The knob 1 has a roughly cylindrical shape, and a flattened shaft 2 is fixed to the tip of the knob 1.

As shown in Figures 7(a) and 7(b), the shaft portion 2 comprises a first shaft portion 2e1, which is a flattened plate-like member in which the horizontal dimension of a cross section perpendicular to the central axis O is greater than the vertical dimension, and a second shaft portion 2e2, which is a flattened plate-like member in which the vertical dimension of a cross section perpendicular to the central axis O is greater than the horizontal dimension. In this embodiment, the first shaft portion 2e1 and the second shaft portion 2e2 are arranged adjacent to each other in the direction of the central axis O and are connected to each other.

As described above, by arranging the first shank 2e1 and the second shank 2e2 adjacent to each other along the central axis O, as shown in FIG. 8(a), when a horizontal bending moment acts on the shank 2, the shank 2 bends in the short direction of the flattened shape of the second shank 2e2, thereby changing the inclination of the brush section 3 relative to the grip section 1. On the other hand, as shown in FIG. 8(b), when a vertical bending moment acts on the shank 2, the shank 2 bends in the short direction of the flattened shape of the first shank 2e1, thereby changing the inclination of the brush section 3 relative to the grip section 1. In other words, regardless of whether a bending moment acts in the vertical or horizontal direction, the cosmetic brush 500 according to this embodiment bends whichever of the first shank 2e1 and the second shank 2e2 is more easily bent (the one whose bending moment direction coincides with the short direction of the flattened shape), thereby changing the inclination of the brush section 3. Therefore, when a user wants to apply cosmetics while tilting the brush portion 3 relative to the knob portion 1, they can use the cosmetic brush 500 without having to consciously adjust its rotational position around the central axis O.

In this embodiment, as shown in Figures 7(a) and 7(b), the first shaft portion 2e1 and the second shaft portion 2e2 are connected by overlapping each other at the overlap region 2e_o at their ends in the direction of the central axis O. This configuration increases the connection region between the first shaft portion 2e1 and the second shaft portion 2e2, thereby alleviating stress concentration.

As shown in Figures 7(a) and 7(b), a brush part 3 for applying cosmetics is fixed to the tip of the shaft part 2.

The brush part 3 has a disk-shaped fixed part 3b attached to the tip of the shaft part 2 and multiple resin bristles 3a extending further from the fixed part 3b toward the tip.

As shown in Figures 7(a) and 7(b), the fixed portion 3b has a disk shape that is symmetrical about the central axis O and is thickened in the direction of the central axis O at the radial center. More specifically, the tip side surface of the fixed portion 3b is substantially flat, while the base side surface of the fixed portion 3b is inclined toward the base end toward the radial center, and the radial center portion has a thickened portion 3b1 that is thickened in the direction of the central axis O.

As described above, by providing the thick portion 3b1 at the radial center of the fixed portion 3b, the tips of each resin bristles 3a fixed to the tip side of the fixed portion 3b are oriented radially inward when cooled, similar to the first to third embodiments.

As described above, in this embodiment, the shaft portion 2 has a first shaft portion 2e1 having a flat shape that is elongated in the horizontal direction, and a second shaft portion 2e2 having a flat shape that is elongated in the vertical direction, with the first shaft portion 2e1 and the second shaft portion 2e2 being adjacent to each other and connected in the direction of the central axis O. By adopting this configuration, regardless of whether a bending moment acts in the vertical or horizontal direction, the first shaft portion 2e1 or the second shaft portion 2e2 that is more easily bent (the one in which the direction of the bending moment coincides with the short side of the flat shape) will bend and deform, changing the inclination of the brush portion 3. Therefore, when a user wishes to apply cosmetics while tilting the brush portion 3 relative to the handle portion 1, they can use the cosmetic brush 500 without having to consciously adjust its rotational position around the central axis O.

In addition, in this embodiment, the first shaft portion 2e1 and the second shaft portion 2e2 are configured to overlap and connect to each other at their ends in the direction of the central axis O. By adopting this configuration, the connection area between the first shaft portion 2e1 and the second shaft portion 2e2 can be increased, thereby alleviating stress concentration.

Next, a cosmetic brush 600 according to a sixth embodiment of the present disclosure will be described using Figures 9(a), 9(b), 10(a), and 10(b). This embodiment has a similar configuration to the first to fifth embodiments, except for the shape of the shaft portion 2, which is different from the first to fifth embodiments. Therefore, the following description will focus on the differences from the first to fifth embodiments. Figures 9(a) and 9(b) show the shape of the cosmetic brush 600 immediately after it has been formed by resin molding and before it has cooled.

As shown in Figures 9(a) and 9(b), the cosmetic brush 600 according to this embodiment comprises a substantially cylindrical gripping portion 1 that is held by the user when using the cosmetic brush 600, a flattened shaft portion 2 fixed to the tip of the gripping portion 1, and a brush portion 3 attached to the tip of the shaft portion 2 for applying cosmetics.

The knob 1 has a roughly cylindrical shape, and a flattened shaft 2 is fixed to the tip of the knob 1.

As shown in Figures 9(a) and 9(b), the shaft portion 2 comprises a first shaft portion 2f1 having a flattened shape in which the horizontal dimension of a cross section perpendicular to the central axis O is greater than the vertical dimension, and a second shaft portion 2f2 having a flattened shape in which the vertical dimension of a cross section perpendicular to the central axis O is greater than the horizontal dimension. In this embodiment, the first shaft portion 2f1 and the second shaft portion 2f2 are arranged adjacent to each other in the direction of the central axis O and are connected to each other.

As shown in Figure 9(b), the first shank 2f1 of this embodiment has a rectangular wave-like undulation shape that undulates in the vertical direction of the shank 2 (the short direction of the flattened shape of the first shank 2f1) toward the central axis O. Similarly, as shown in Figure 9(a), the second shank 2f2 has a rectangular wave-like undulation shape that undulates in the horizontal direction of the shank 2 (the short direction of the flattened shape of the second shank 2f2) toward the central axis O.

By arranging the first shank 2f1 and the second shank 2f2 adjacent to each other along the central axis O, as shown in FIG. 10(a), when a horizontal bending moment acts on the shank 2, the shank 2 bends in the short direction of the flattened shape of the second shank 2f2, thereby changing the inclination of the brush section 3 relative to the grip section 1. On the other hand, as shown in FIG. 10(b), when a vertical bending moment acts on the shank 2, the shank 2 bends in the short direction of the flattened shape of the first shank 2f1, thereby changing the inclination of the brush section 3 relative to the grip section 1. In other words, regardless of whether a bending moment acts in the vertical or horizontal direction, the cosmetic brush 600 according to this embodiment bends whichever of the first shank 2f1 and the second shank 2f2 is more easily bent (the one in which the direction of the bending moment coincides with the short direction of the flattened shape), thereby changing the inclination of the brush section 3. In particular, in this embodiment, the first shaft portion 2f1 and the second shaft portion 2f2 each have a wavy shape, which allows them to be easily bent in the short direction of the flat shape while changing the curvature of the wavy shape. Therefore, when a user wants to apply cosmetics while tilting the brush portion 3 relative to the knob portion 1, they can use the cosmetic brush 600 without having to consciously adjust its rotational position around the central axis O.

Furthermore, because the first shaft portion 2f1 and the second shaft portion 2f2 each have a wavy shape, when the cap member 20 is removed from the cosmetic container 10 while the lower portion of the shaft portion 2 is immersed in cosmetic material, as shown in Figure 3, the cosmetic material adhering to the rectangular wave-like wavy shape of the shaft portion 2 is retained in the peaks and valleys of the wavy shape, allowing the user to continue using the cosmetic material supplied to the brush portion 3 sequentially from the wavy shape without having to repeatedly reapply the cosmetic material to the brush portion 3.

In this embodiment, as shown in Figures 9(a) and 9(b), the first shaft portion 2f1 and the second shaft portion 2f2 are connected by overlapping each other at the overlap region 2f_o at the ends in the direction of the central axis O. This configuration increases the connection region between the first shaft portion 2f1 and the second shaft portion 2f2, thereby alleviating stress concentration.

As shown in Figures 9(a) and 9(b), a brush part 3 for applying cosmetics is fixed to the tip of the shaft part 2.

The brush part 3 has a disk-shaped fixed part 3b attached to the tip of the shaft part 2 and multiple resin bristles 3a extending further from the fixed part 3b toward the tip.

As shown in Figures 9(a) and 9(b), the fixed portion 3b has a disk shape that is symmetrical about the central axis O and is thickened in the direction of the central axis O at the radial center. More specifically, the tip side surface of the fixed portion 3b is substantially flat, while the base side surface of the fixed portion 3b is inclined toward the base end toward the radial center, and the radial center portion has a thickened portion 3b1 that is thickened in the direction of the central axis O.

As described above, by providing the thick portion 3b1 at the radial center of the fixed portion 3b, the tips of each resin bristles 3a fixed to the tip side of the fixed portion 3b are oriented radially inward when cooled, similar to the first to third embodiments.

While this disclosure has been described based on various drawings and examples, it should be noted that those skilled in the art would easily be able to make various modifications and alterations based on this disclosure. Therefore, it should be noted that these modifications and alterations are included within the scope of the present invention. For example, the functions contained in each component can be rearranged so as not to cause logical inconsistencies, and multiple components can be combined into one or divided. It should be understood that these are also included within the scope of the present invention.

For example, in the first to sixth embodiments, the resin bristles 3a are configured to be arranged in a double ring shape, but this is not limited to this. The resin bristles 3a may be arranged in an elliptical ring shape, or in a single ring or triple or more ring shapes.

Furthermore, in the first to sixth embodiments, the cosmetic brushes 100 to 600 have been described assuming that they are primarily used as manicure brushes, but this is not limited to this. The cosmetic brushes 100 to 600 may also be used as cosmetic brushes for applying other cosmetics, for example.

Cosmetic brushes 100 to 600 with simplified structures can be provided.

1 Handle portion 1a Axial rib 1b Annular protrusion 2 Shank portion 2a Convex portion 2b Concave portion 2b1 Through hole 2b2 Bottomed hole 2c Convex portion 2c1 Inclined surface 2d Wave shape 2e1 First shaft portion 2e2 Second shaft portion 2e_o Overlap region 2f1 First shaft portion 2f2 Second shaft portion 2f_o Overlap region 2t Reduced diameter portion 3 Brush portion 3a Resin bristles 3a1 Outer bristles 3a2 Inner bristles 3b Fixing portion 3b1 Thick portion 10 Cosmetic container 11 Mouth portion 11a Male thread portion 12 Shoulder portion 13 Body portion 14 Bottom portion 20 Cap member 21 Peripheral wall 21a Female thread portion 21b Anti-rotation rib 21c Engagement protrusion 22 Top wall 100, 200, 300, 400, 500, 600 Cosmetic brush O Central axis S Containment space

Claims (2)

A knob and
a shaft portion fixed to the knob portion;
A cosmetic brush comprising: a brush portion provided at the tip of the shaft portion,
The shaft portion and the brush portion are integrally molded,
the shaft portion has a flat shape in which the vertical and horizontal dimensions of a cross section perpendicular to the central axis are different,
the shaft portion has a protrusion that protrudes in a short direction of the flat shape,
A cosmetic brush characterized in that the side of the convex portion has an inclined surface that slopes toward the central axis direction toward the longitudinal center position of the flat shape, and the convex portion is not located at the longitudinal center position of the flat shape. The cosmetic brush according to claim 1, wherein the grip portion, shaft portion, and brush portion are integrally molded.