toothbrush

Abstract

By rationally designing the distribution and area of ​​the bristle holes, particularly by gradually decreasing the area of ​​the bristle holes from the center of the head outwards in the width direction, we can mitigate problems such as warping and cracking that may occur in the toothbrush head, thereby improving product durability and the stability of the production process. [Solution] A toothbrush comprising a head portion having a bristle surface composed of an outer peripheral region A located on the outer periphery of the bristle surface, a central region C, and two side regions B, and a handle body provided on the rear end side of the head portion, wherein the bristle surface includes bristle holes S, bristle holes M having an area 1.2 to 25 times the area of ​​the bristle holes S, and bristle holes L having an area 1.2 to 25 times the area of ​​the bristle holes M, wherein in the side region B, 80% or more of the total number of bristle holes are bristle holes M, and the angle between the minor axis of the bristle holes M and the length direction of the head portion is less than 45°, and in the central region C, 80% or more of the total number of bristle holes are bristle holes L, and the angle between the minor axis of the bristle holes L and the length direction of the head portion is less than 45°.

Description

TECHNICAL FIELD

[0001] The present invention relates to toothbrushes, and in particular to wide-head toothbrushes.

BACKGROUND ART

[0002] As people's awareness of oral health increases, toothbrushes, as daily cleaning tools, have their designs and functions continuously improved and optimized. Consumer demand for toothbrushes has evolved from a simple cleaning function to comprehensive requirements for gum protection, cleaning performance in the cervical region of teeth, and usage comfort. Among the many toothbrush designs on the market, conventional compact-head toothbrushes can penetrate small gaps in the oral cavity, but due to the limited number of bristles, their cleaning efficiency is low, and the contact area with the gums is small, making it difficult to achieve a sufficient massage effect on the gums.

[0003] In contrast, wide-head toothbrushes have a large number of bristles and a high bristle density, which can effectively improve cleaning efficiency. However, these designs have certain limitations. For example, while increasing the bristle tuft density by increasing the number of tuft holes, reducing the pitch between adjacent tuft holes will lower the strength after tufting, and further cause quality problems such as warping or cracking of the head portion, which may further affect the durability of the toothbrush during use. In particular, for toothbrushes with a wide-head design, due to the increased width, compared with conventional compact-type toothbrushes, the moment in the width direction is larger, the resistance to stress acting in the width direction is weaker, and warpage is more likely to occur on the outer side in the width direction. Furthermore, the existing bristle designs for wide heads are simplistic, making it difficult to satisfy the two requirements of tooth surface cleaning and gum protection at the same time.

[0004] Patent Document 1 reports a toothbrush that aims to provide a toothbrush that provides a soft massage sensation to a wide area of ​​gums while ensuring high cleaning performance at the gum line. In this toothbrush, the outer bristle density is defined as the total number of bristles constituting the plurality of outer bristle bundles divided by the area of ​​the outer bristle area, and the inner bristle density is defined as the total number of bristles constituting the plurality of inner bristle bundles divided by the area of ​​the inner bristle area, and the bristle density ratio expressed as outer bristle density / inner bristle density is 1.4 or more and 2.0 or less. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2017 / 204204 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the hair design described in Patent Document 1 still has room for improvement in terms of the strength of the head after hair implantation and the density of the hair.

[0007] The inventors of this invention have diligently conducted research to solve the above problems and have found that by rationally designing the distribution and area of ​​the bristle holes, and in particular by gradually reducing the area of ​​the bristle holes from the center of the head outwards in the width direction, it is possible to mitigate problems such as warping and cracking that may occur in the toothbrush head, thereby improving the durability of the product and the stability of the production process. Furthermore, it is possible to improve the density of the bristles, and by designing separate bristle areas that contact the tooth surface and bristle areas that contact the gums, it is possible to provide cleaning ability on the tooth surface and comfort of contact with the gums, and to provide effective cleaning ability with moderate force without requiring excessive force. [Means for solving the problem]

[0008] The main points of this invention are as follows:

[0009] [1] A toothbrush comprising a head portion having a bristle surface and a handle body provided on the rear end side of the head portion, The bristle-flocked surface is composed of an outer peripheral region A located on the outer periphery of the bristle-flocked surface, a central region C adjacent to the outer peripheral region A in the length direction of the head and located midway in the width direction of the head, and two side regions B other than the outer peripheral region A and the central region C. The hair implantation surface includes hair implantation holes S, hair implantation holes M, and hair implantation holes L, and in the plane on which the hair implantation surface is located, the area of ​​the hair implantation holes M is 1.2 to 25 times the area of ​​the hair implantation holes S, and the area of ​​the hair implantation holes L is 1.2 to 25 times the area of ​​the hair implantation holes M. In the outer peripheral region A, both sides of the head width direction, more than 80% of the total number of hair implantation holes are hair implantation holes S. In the aforementioned lateral region B, more than 80% of the total number of hair implantation holes are hair implantation holes M, and the angle between the minor axis of the hair implantation hole M and the length direction of the head portion is less than 45°. A toothbrush characterized in that, in the central region C, 80% or more of the total number of bristle holes are bristle holes L, and the angle between the minor axis of the bristle holes L and the length direction of the head is less than 45°.

[0010] [2] The toothbrush according to [1], characterized in that the bristle holes M and L are substantially elliptical, including elliptical, track-shaped, egg-shaped, olive-shaped, and shapes in which the two radii of the minor axis of these shapes are of different lengths, shapes in which the major axis of these shapes is curved, and shapes in which the two radii of the minor axis of these shapes are of different lengths and the major axis is curved.

[0011] [3] The total number of hair implantation holes in the central region C is 4 to 30, and they are formed in a single row extending along the length of the head portion, and the hair implantation holes L in the central region C are of the same shape. The toothbrush according to [1] or [2], wherein bristle holes L may be present at the top and bottom of the bristle surface of the outer peripheral region A, and if bristle holes L are present, the bristle holes L are the same shape as the bristle holes L of the central region C and are located on the extension of the row of bristle holes of the central region C.

[0012] [4] The toothbrush according to [2], characterized in that the shape of the bristle holes L is such that the long axis is curved, or the two radii of the short axis are different and the long axis is curved, and the angle between the short axis of the bristle holes L and the length direction of the head is less than 10°.

[0013] [5] In the central region C, there is a point P in the row of hair implantation holes that extends along the length direction of the head portion, which may be located at the midpoint of the central region C in the length direction of the head portion. The toothbrush described in [4] is characterized in that the curved protrusions of the bristle holes L located between point P and the top of the bristle surface are directed toward the top of the bristle surface, and the curved protrusions of the bristle holes L located between point P and the bottom of the bristle surface are directed toward the bottom of the bristle surface.

[0014] [6] The toothbrush according to [5], characterized in that, with the exception of the bristle holes located at point P, all of the bristle holes in the central region C are bristle holes L, each of the bristle holes L is the same in shape and size, and the angle between the short axis direction of the bristle holes L and the length direction of the head is 3° or less in all cases.

[0015] [7]. The toothbrush according to [1] or [2], characterized in that, in the lateral region B, the shape of each of the bristle holes M is the same, and the angle between the minor axis of the bristle holes M and the length direction of the head is 5° or more.

[0016] [8]. The toothbrush according to [1] or [2], characterized in that the total number of bristle holes in one of the lateral regions B is 4 to 30, and all of the bristle holes are bristle holes M.

[0017] [9]. The toothbrush according to [8], characterized in that the bristle holes M are identical in shape and size, the angle between the minor axis of the bristle holes M and the length direction of the head is the same, and the two lateral regions B are symmetrical with respect to the center line in the width direction of the head.

[0018]

[10] . The total number of bristle tuft holes in the outer peripheral region A is 10 to 50, the shape of the bristle tuft holes S in the outer peripheral region A is a substantially perfect circle, the number thereof is 8 or more, and the sizes of the bristle tuft holes S are the same, the toothbrush according to [1] or [2].

[0019]

[11] . The bristle tuft hole M and the bristle tuft hole L each have 2 to 6 bristle tuft structures formed by partition plates, and the partition plates are formed integrally with the bristle tuft surface or formed separately from the bristle tuft surface, The number of bristle tuft structures possessed by the bristle tuft hole M is less than the number of bristle tuft structures possessed by the bristle tuft hole L, the toothbrush according to [1] or [2].

[0020]

[12] . The bristle tuft hole M has two bristle tuft structures formed by one partition plate, and the bristle tuft hole L has three bristle tuft structures formed by two partition plates or four bristle tuft structures formed by three partition plates, the toothbrush according to

[11] .

[0021]

[13] . In the length direction of the head portion, the bristle tuft holes in the central region C and the adjacent bristle tuft holes in the side region B are arranged alternately, the toothbrush according to [1] or [2].

[0022]

[14] . In the length direction of the head portion, the bristle tuft holes in the central region C and the corresponding bristle tuft holes in the outer peripheral region A are arranged alternately, the toothbrush according to [1] or [2].

[0023]

[15] . The angle formed between the partition plate of the bristle tuft hole M in the side region B and the width direction of the head portion is smaller than the angle formed between the partition plate of the bristle tuft hole L in the central region C closest to the bristle tuft hole M and the width direction of the head portion, the toothbrush according to

[12] .

[0024]

[16] . The bristle tufting hole L has 2 to 6 bristle tufting structures formed by partition plates, and an intersection of at least two extension lines of the partition plates included in one said bristle tufting hole L is located on the point P side of the bristle tufting hole, the toothbrush according to [5].

[0025]

[17] . The bristle tufting hole S, the bristle tufting hole M and the bristle tufting hole L adopt flat wire tufting, the toothbrush according to [1] or [2].

[0026]

[18] . The bristle tufting hole L has 2 to 6 bristle tufting structures formed by partition plates, each bristle tufting structure adopts flat wire tufting, and an intersection of at least two extension lines of the flat wires of the bristle tufting structures in one bristle tufting hole L is located on the point P side of the bristle tufting hole, the toothbrush according to [5].

[0027]

[19] . The bristle tufting hole M in the side region B has 2 to 6 bristle tufting structures formed by partition plates, The intersection of the extension line of the flat wire of the bristle tufting hole S in both side regions in the head portion width direction of the outer peripheral region A and the extension line of the flat wire of the bristle tufting structure of the closest bristle tufting hole M in the side region B is located in the region where no bristle tufting hole exists between the row formed by the bristle tufting holes S in the head portion length direction and the row formed by the bristle tufting holes M in the head portion length direction, the toothbrush according to

[18] .

[0028]

[20] . The area of the bristle tufting hole M is 1.4 to 2.4 times the area of the bristle tufting hole S, and the area of the bristle tufting hole L is 2.5 to 4.0 times the area of the bristle tufting hole S, the toothbrush according to [1] or [2]. [Effects of the Invention]

[0029] According to the present invention, it is possible to provide a toothbrush that can alleviate problems such as warping and cracking that may occur in the head of a toothbrush, especially in the head of a wide-head toothbrush, thereby improving the durability of the product and the stability of the manufacturing process. Furthermore, it is possible to improve the density of the bristles, and by designing separate bristle areas that contact the tooth surface and bristle areas that contact the gums, it is possible to provide cleaning ability for the tooth surface and comfort for contact with the gums, and to provide effective cleaning ability with moderate force without requiring excessive force. [Brief explanation of the drawing]

[0030] [Figure 1] This is a schematic diagram showing the head portion of one embodiment of the toothbrush of the present invention. [Figure 2] This is a schematic diagram showing the various regions of the bristle surface of the head portion of a toothbrush according to one embodiment of the present invention. [Figure 3] This is a schematic diagram showing the shape of the bristle holes in the plane where the bristle surface of the toothbrush of the present invention is located, with the dashed lines indicating the major and minor axes of each shape. [Figure 4] This is a schematic diagram showing the bristle surface of the toothbrush of the present invention. [Figure 5] This figure shows the bristle structure having bristle implantation holes according to one embodiment of the toothbrush of the present invention. [Figure 6] This is a schematic diagram showing the bristle surface of a toothbrush according to a specific embodiment of the present invention. [Modes for carrying out the invention]

[0031] The embodiments of the toothbrush of the present invention will be described below with reference to Figures 1 to 6.

[0032] The following embodiments represent one aspect of the present invention and do not limit it; they can be modified at will within the scope of the technical idea of ​​the present invention. Furthermore, the descriptions in the following drawings are for illustrative purposes only and do not represent the actual structure, nor do they reflect the scale, numbers, etc., of each structure.

[0033] Figure 1 is a front view showing a part of the toothbrush of this embodiment. As shown in Figure 1, it comprises a head portion 1 and a handle body 2 located at the rear end of the head portion. The head portion 1 may be integrally formed with the handle body or may be detachably connected. One side of the head portion 1 is a bristle surface 11, and the bristle surface 11 is provided with a plurality of bristle holes 13 into which bundles of bristles 12 are planted. The thickness direction of the head portion 1 perpendicular to the bristle surface 11 is the Z direction, the extension direction of the handle body 2 and the length direction of the head portion 1 are the X direction, the direction perpendicular to the X direction and the Z direction and the width direction of the head portion 1 are the Y direction.

[0034] Refer to Figure 2, a schematic diagram showing each region of the bristle surface of the head portion in one embodiment of the toothbrush of the present invention. In the toothbrush of the present invention, the bristle surface is composed of an outer peripheral region A located on the outer periphery of the bristle surface, a central region C adjacent to the outer peripheral region A in the length direction of the head portion and located in the middle in the width direction of the head portion, and two side regions B other than the outer peripheral region A and the central region C. That is, moving outward from the center point of the head portion along the width direction of the head portion, the order is central region C, side regions B, and outer peripheral region A. Of these, outer peripheral region A further includes both side regions in the width direction of the head portion, the tip region of the bristle surface, and the bottom region of the bristle surface, and is the region located outside both side regions in the width direction of the head portion and the side regions B in the width direction of the head portion, that is, the portion sandwiched between the two dashed lines on the right side of Figure 2.

[0035] Figure 2 should be understood as a diagram showing the relative positions of regions A through C, rather than the actual divisions between regions A through C.

[0036] The grafted surface includes graft holes S, M, and L. In the plane on which the grafted surface is located, the area of ​​graft hole M is 1.2 to 25 times the area of ​​graft hole S, and the area of ​​graft hole L is 1.2 to 25 times the area of ​​graft hole M, more preferably the area of ​​graft hole M is 1.2 to 10 times the area of ​​graft hole S, and the area of ​​graft hole L is 1.2 to 10 times the area of ​​graft hole M, and even more preferably the area of ​​graft hole M is 1.2 to 3.0 times the area of ​​graft hole S, and the area of ​​graft hole L is 1.2 to 3.0 times the area of ​​graft hole M. Of these, the area of ​​graft hole S is defined as the area of ​​the graft hole with the largest number of graft holes having the same shape and area in the outer peripheral region A. For example, if there are 10 circular hair implantation holes with area n and 16 circular hair implantation holes with area m in the outer perimeter region, the area of ​​hair implantation hole S is determined to be m. If all the hair implantation holes in the outer perimeter region A are different, it is defined as the average area of ​​the hair implantation holes present in both sides of the head width direction.

[0037] In one embodiment, the area of ​​the hair transplant hole M is 1.4 to 2.4 times the area of ​​the hair transplant hole S, and the area of ​​the hair transplant hole L is 2.5 to 4.0 times the area of ​​the hair transplant hole S.

[0038] In the outer peripheral region A, in the head width direction, more than 80% of the total number of grafted hair holes are grafted hair holes S; in the lateral region B, more than 80% of the total number of grafted hair holes are grafted hair holes M; and in the central region C, more than 80% of the total number of grafted hair holes are grafted hair holes L.

[0039] Due to the above limitations, in this invention, the area of ​​the main hair implantation holes gradually decreases in the central region C, lateral region B, and outer peripheral region A, which are sequentially located outward along the width direction of the head portion from the center point of the head portion. As those skilled in the art will understand, the regions on both sides of the head portion width direction of the central region C, lateral region B, and outer peripheral region A represent regions mainly composed of large-area hair implantation holes L, medium-area hair implantation holes M, and small-area hair implantation holes S, respectively. Therefore, it is usually rare for hair implantation holes to be located at the boundary of adjacent regions, and if such rare cases exist, they are assigned to the region where a larger area is located, according to the area distribution of hair implantation holes in each region.

[0040] Furthermore, the shapes of the hair implantation holes S, M, and L are not particularly limited and may be general hair implantation hole shapes in the field. For example, hair implantation holes M and L may be rectangular, rounded rectangular, or substantially elliptical, preferably substantially elliptical, and in the central region C and lateral region B, the angle between the minor axis of these substantially elliptical shapes and the length direction of the head portion (X direction) is less than 45°, more preferably less than 30°. Due to the above limitations, in the present invention, the substantially elliptical shapes present in the central region C and lateral region B have their minor axis substantially coincide with the length direction of the head portion and their major axis substantially coincide with the width direction of the head portion. The substantially elliptical shape of hair implantation holes L and M improves the strength of the head portion under stress and reduces cracking.

[0041] The present invention features a configuration in which specific bristle holes are distributed in specific areas of the bristle surface. As a result, the area of ​​bristle holes decreases from the central area outward in the width direction on the bristle surface of the head. This effectively reduces the impact of large-area bristle holes on the strength of the bristle surface, and effectively disperses and mitigates stress acting in the width direction. On the other hand, this bristle design can effectively improve the density of bristles across the entire bristle surface, especially in the central area C that contacts the tooth surface, while providing a soft touch in the outer peripheral area A that contacts the gums. This provides both cleaning ability against the tooth surface and comfort in contact with the gums, enabling effective cleaning without requiring excessive force.

[0042] Referring to Figure 3, in embodiments of the present invention, the substantially elliptical shape includes elliptical, track-shaped, egg-shaped, olive-shaped, and shapes of these shapes in which the two radii of the minor axis are of different lengths, shapes of these shapes in which the major axis is curved, and shapes of these shapes in which the two radii of the minor axis are of different lengths and the major axis is curved. In each figure in Figure 3, dashed lines consisting of line segments schematically represent the major axis, and dashed lines consisting of dots schematically represent the minor axis. These shapes described herein include slight modifications insofar as they are recognizable to those skilled in the art.

[0043] Furthermore, the above shapes can be modified as appropriate, including shapes with two different radii along the minor axis, shapes with a curved major axis, and shapes with two different radii along the minor axis and a curved major axis. Taking an ellipse as an example, if the two radii along the minor axis are different, a roughly ellipse is formed with different arc curvatures on both sides of the major axis. When the major axis of an ellipse is curved, a shape similar to a kidney, a pea, or a cashew nut is formed.

[0044] The material of the head portion 1 is obtained, for example, by injection molding a resin. As the resin, one or more commonly used for toothbrush handles can be used, for example, one or more selected from polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polycyclohexylene dimethylene terephthalate (PCT), polyethylene terephthalate cyclohexanedimethane (PCTG), polyacetal (POM), polystyrene (PS), acrylonitrile-butadiene-styrene resin (ABS), cellulose propionate (CP), polyarylate, polycarbonate, or acrylonitrile-styrene copolymer resin (AS).

[0045] In one embodiment, the head portion has a wide head design, which means that, for example, six or more rows of bristles, such as 6 to 12 rows or 8 to 12 rows, are planted in the width direction of the toothbrush. In a wide head design, for example, the width of the head portion is 14 mm to 20 mm, preferably 15 mm to 19 mm.

[0046] Figure 4 shows a schematic diagram of a possible embodiment of the hair flocking surface of the present invention, but it should be understood that the arrangement of the hair flocking surface of the present invention is not limited thereto. A detailed explanation follows below.

[0047] <Central area C> In one embodiment of the present invention, the total number of hair implantation holes in the central region C is 4 to 30, preferably 4 to 20. More preferably 4 to 10. Each hair implantation hole is formed in a row extending along the length direction of the head portion, and the hair implantation holes L are identical or different in shape and are identical or different in size.

[0048] Preferably, the bristle implantation holes L in the central region C are identical in shape, and the angle between the short axis direction and the length direction of the head is less than 30°, more preferably less than 10°. This configuration makes it possible to achieve both a denser feel of bristles and prevention of head curvature.

[0049] Preferably, the shape of the bristle holes L may be curved along its long axis, or the two radii of its short axis may be different, and the angle between the short axis direction of the bristle holes L and the length direction of the head is less than 10°. The bristle holes L are preferably curved along their long axis, such as elliptical or track-shaped. This configuration further enhances both the density of the bristles and the prevention of head warping. Specifically, the curved shape avoids an increase in moment due to the bristle holes becoming excessively long in the width direction of the head, and allows for better distribution of the force applied in the width direction of the head on the bristle surface of the toothbrush.

[0050] In the curved shape described above, the curvature angle of the major axis is generally less than 45°, more preferably less than 30°, and even more preferably between 10° and 20°. By setting it within this range, the technical effects of the present invention can be obtained more effectively.

[0051] In one embodiment, in the central region C, the curved protrusions of the long axis of the hair implantation holes L are all facing either the top of the hair implantation surface or the bottom of the hair implantation surface.

[0052] In one embodiment, in the central region C, a row of bristles extending along the length of the head portion contains a point P which may be located at the midpoint of the length of the head portion in the central region C. The convex portion of the bristles located between point P and the top of the bristles surface has a curved major axis and faces the top of the bristles surface, while the convex portion of the bristles located between point P and the bottom of the bristles surface has a curved major axis and faces the bottom of the bristles surface.

[0053] This configuration allows for better distribution of force in the longitudinal direction of the head on the bristle surface of the toothbrush, and also allows opposing forces from the bristle holes L to cancel each other out.

[0054] Preferably, in the central region C, with the exception of the hair implantation hole located at point P, all hair implantation holes in the central region C are hair implantation holes L, the shape and size of the hair implantation holes L are the same, and the angle between the short axis direction of the hair implantation hole L and the length direction of the head portion is 3° or less in all cases.

[0055] Preferably, in the central region C, point P is located at the midpoint in the length direction of the head portion of the central region C, and all hair implantation holes in the central region C, except for the hair implantation hole located at point P, are hair implantation holes L, the shape and size of the hair implantation holes L are the same, the intersection of their minor axis and major axis is located approximately on the midline in the width direction of the head portion, and the angle between the minor axis direction of the hair implantation hole L and the length direction of the head portion is 3° or less in both cases.

[0056] By having the above configuration, the central area C of the toothbrush can be made sufficiently dense with bristles, achieving both a dense bristle feel and prevention of head warping. In particular, during use, the bristles in the central area C can thoroughly and efficiently clean the tooth surface.

[0057] <Lateral region B> In one embodiment of the present invention, of the two side regions B on the bristle surface of the head portion, the total number of bristle holes in each side region B is 4 to 30, preferably 4 to 20, and more preferably 4 to 10.

[0058] Preferably, in the lateral region B, the shape of the bristles M is the same, and the angle between the minor axis of the bristles M and the length direction of the head is 5° or more. That is, by aligning the major axes of the approximately elliptical bristles in the lateral region B at an angle to the width direction of the head, the influence of stress acting in the width direction of the head can be reduced.

[0059] More than 80% of the total number of bristle holes in the lateral region B are bristle holes M, preferably more than 90% are bristle holes M, and more preferably all bristle holes are bristle holes M. By having all bristle holes M, the curvature in the width direction of the head is reduced, while in terms of usability, the bristle density of the lateral region B is between the bristle density of the central region C and the bristle density of the outer peripheral region A. As a result, the bristles of the outer peripheral region A are properly supported during cleaning as "sides" of the bristle surface, and the bristles of the central region C can also bend appropriately. This ensures a smooth transition in cleaning ability and feel between the outer peripheral region A and the central region C, and when brushing teeth, it is possible to avoid applying too much force due to the softness of the outer peripheral region A, causing the dense bristles of the central region C to directly act on the teeth with great force and damaging the teeth.

[0060] Preferably, the bristle holes M are identical in shape and size, the angle between the minor axis of the bristle holes M and the length direction of the head is the same, and the two lateral regions B are symmetrical with respect to the center line in the width direction of the head. That is, the bristle surface of the head has roughly fishbone-like "sides" formed by the roughly elliptical bristle holes in the lateral regions B, which further increases the strength of the head and prevents warping in the width direction of the head.

[0061] Preferably, in the lateral region B, the hair implantation holes M are oval or track-shaped.

[0062] By providing the toothbrush with the lateral region B configured as described above, the density of the bristles can be increased, the curvature of the head can be reduced, and cleaning ability and gum comfort can be improved.

[0063] <Outer area A> The total number of hair implantation holes in the outer peripheral region A is 10 to 50, preferably 10 to 40. The shape of the hair implantation holes S in the outer peripheral region A is not particularly limited, but is preferably approximately circular, with 8 or more holes, and all of the same size.

[0064] Preferably, the hair implantation holes in both sides of the head width direction of the outer peripheral region A are both hair implantation holes S, and the shape and size of these hair implantation holes S are the same.

[0065] With the above configuration, the curvature in the width direction of the head is reduced in the outer peripheral region A, and a soft touch is provided to the gums.

[0066] Furthermore, hair implantation holes L may exist at the top and bottom of the hair implantation surface in the outer peripheral region A. If the shapes of the hair implantation holes L in the central region C are identical, then the hair implantation holes L that may exist at the top and bottom of the hair implantation surface in the outer peripheral region A will also have the same shape as the hair implantation holes L in the central region C and will be located on the extension of the row of hair implantation holes in the central region C.

[0067] Preferably, there is one bristle hole L at the top and bottom of the bristle surface in the outer peripheral region A, and the bristle holes L at the top and bottom of the bristle surface are identical in shape and size to the bristle holes L in the central region C, and the intersection of their short axis and long axis is located approximately on the midline in the width direction of the head, and the angle between the short axis direction of the bristle hole L and the length direction of the head is 3° or less in both cases. That is, in the middle part in the width direction of the head, except for the position of point P which may exist, there is a row of bristle holes L with the same shape and size from the tip of the bristle surface to the bottom of the bristle surface.

[0068] <Relative positional relationship of hair transplant pores in areas A-C> The following describes the relative positional relationship of the hair follicles in regions A to C in one embodiment of the present invention.

[0069] In one embodiment of the present invention, the hair implantation holes in the central region C and the hair implantation holes in the adjacent side region B are arranged alternately in the length direction of the head. Here, "alternating arrangement" means, for example, that when viewed from the width direction of the head, the hair implantation holes in the side region B are located in the side region B corresponding to the space between two adjacent hair implantation holes in the central region C. In other words, the long axis of the hair implantation holes in the side region B points not to the hair implantation holes in the central region C, but to the space between adjacent hair implantation holes in the central region C. With this configuration, since the hair implantation holes in the central region C and the hair implantation holes in the side region B are not substantially on the same line in the width direction of the head, warping in the width direction of the head can be avoided.

[0070] In one embodiment of the present invention, the bristles in the central region C and the corresponding bristles in the outer peripheral region A are arranged alternately in the length direction of the head. Here, "arranged alternately" means, for example, that when viewed from the width direction of the head, the bristles in the outer peripheral region A are located in the outer peripheral region A that corresponds to the space between two adjacent bristles in the central region C. With this configuration, the bristles in the central region C and the bristles in the outer peripheral region A are not substantially on the same line in the width direction of the head, and furthermore, warping in the width direction of the head can be avoided.

[0071] <Hair transplant structure> In one embodiment of the present invention, the flocking holes M and L each have a flocking structure of two to six flocking plates formed by partition plates, and the partition plates are formed integrally with or separately from the flocking surface.

[0072] The number of hair follicle structures in hair follicle M is less than the number of hair follicle structures in hair follicle L.

[0073] In one embodiment, the bristles implanted in the hole M has two bristles implanted by one partition plate, and the bristles implanted in the hole L has three bristles implanted by two partition plates or four bristles implanted by three partition plates.

[0074] The presence of partition plates can improve the strength of the bristle holes, and is also advantageous in maintaining the proper distribution of bristle bundles and the firmness of the bristle structure, as well as maintaining the flatness of the brush surface.

[0075] Figure 5 shows a cross-section of a bristled hole M in the thickness direction of the head portion along its long axis, having, for example, two bristled structures formed by a single partition plate. The drawing shows a schematic diagram in which the bristled hole has two bristled structures BU, each having one bundle of bristles implanted in a flat line manner, formed by a single partition plate BS which may be flush with the bristled surface or slightly lower than the bristled surface. For the above structure of partitioning the bristled hole with a partition plate, one can refer, for example, to the partition plate in the existing art WO2023 / 058672A1. However, it should be understood that the structure of the partition plate can be adaptively adjusted according to the shape of the bristled hole of the present invention.

[0076] In one embodiment of the present invention, the angle between the partition plate of the bristles in the bristles in the lateral region B and the width direction of the head is smaller than the angle between the partition plate of the bristles in the bristles in the central region C, which is closest to the bristles in the bristles in the lateral region B, and the width direction of the head. This allows the partition plate to reinforce the structure of the head and further reduces warping in the width direction of the head.

[0077] In one embodiment of the present invention, in the central region C, the shape of the bristles implanted in This further reduces warping in the width direction of the head section.

[0078] <Hair transplantation method> The method for implanting the bristles in the present invention is not particularly limited, and conventional well-known methods can be used. Examples include the flat wire implantation method, in which a bristle bundle is folded in half and a flat wire sandwiched between the bristles is driven into the implantation hole; the heat fusion method, in which the lower end of the bristle bundle is pressed into the molten resin that will form the implantation area to fix it in place; and the in-mold method, in which the lower end of the bristle bundle is heated to form a molten mass, and then the molten resin is injected into a mold to form the implantation area.

[0079] In one embodiment of the present invention, hair implantation holes S, M, and L employ a flat wire type hair implantation method.

[0080] In one embodiment of the present invention, the bristle flocking hole L has two to six bristle flocking structures formed by partition plates, and flat wire bristle flocking is employed in each bristle flocking structure, and the intersection of at least two extensions of the flat wires of each bristle flocking structure of a single bristle flocking hole L is located on the side of point P of the bristle flocking hole. This makes it possible to further reduce warping in the width direction of the head.

[0081] In one embodiment of the present invention, the bristles M of the side region B have two to six bristles formed by partition plates, and the intersection of the extension of the flat line of the bristles S in both sides of the head width direction of the outer peripheral region A and the extension of the flat line of the bristles M of the side region B that is closest to it is located in a region where there are no bristles between the row of bristles S in the head length direction and the row of bristles M in the head length direction. This makes it possible to further reduce warping in the head width direction.

[0082] Figure 6 shows a schematic diagram of the distribution of flocking holes with connecting parts in one embodiment. The black areas in the figure are simply to make the structure clearer and do not represent a specific structure of the flocking holes or flocking bundles. In the figure, the central region C has a flocking hole at the midpoint P in the longitudinal direction and six flocking holes L that curve toward point P, and each of the six flocking holes has two partition plates, and their extensions intersect on the side of point P. The side regions B on both sides in the width direction of the central region C each have six inclined flocking holes M, and each of the six flocking holes M has one partition plate. The outer peripheral region A has six flocking holes S on both sides in the width direction of the head, and has one flocking hole L and two flocking holes S at the top and bottom of the flocked surface, respectively. The flocking holes S do not have partition plates. The flocking holes on both sides in the width direction of the head of the central region C and side regions B, and the central region C and outer peripheral region A are arranged alternately.

[0083] According to the present invention, it is possible to provide a toothbrush that can alleviate problems such as warping and cracking that may occur in the head of a toothbrush, especially in toothbrushes with a wide head design, thereby improving the durability of the product and the stability of the production process. Furthermore, it is possible to improve the density of the bristles, and by designing separate bristle areas that contact the tooth surface and bristles that contact the gums, it is possible to provide cleaning ability for the tooth surface and comfort in contact with the gums, and to provide effective cleaning ability without requiring excessive force.

[0084] Preferred embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these examples. The shapes and combinations of the constituent members shown in the above examples are merely examples, and can be modified in various ways based on design requirements, etc., without departing from the spirit of the present invention. [Industrial applicability]

[0085] This invention can be applied to toothbrushes. [Explanation of Symbols]

[0086] 1…Head part 2...Handle body 11… Hair transplant surface 12…Hair bundles 13… Hair transplant pores A...Peripheral region A of the hair transplanted surface B... Lateral region of the hair transplanted area B C...Central area of ​​the hair transplant surface C S... Hair transplant hole S M... Hair transplant hole M L... Hair transplant hole L BU... Hair transplant unit BS...partition plate

Claims

1. A toothbrush comprising a head portion having a bristle surface and a handle body provided on the rear end side of the head portion, The bristle-flocked surface is composed of an outer peripheral region A located on the outer periphery of the bristle-flocked surface, a central region C adjacent to the outer peripheral region A in the length direction of the head and located midway in the width direction of the head, and two side regions B other than the outer peripheral region A and the central region C. The hair implantation surface includes hair implantation holes S, hair implantation holes M, and hair implantation holes L, and in the plane on which the hair implantation surface is located, the area of ​​the hair implantation holes M is 1.2 to 25 times the area of ​​the hair implantation holes S, and the area of ​​the hair implantation holes L is 1.2 to 25 times the area of ​​the hair implantation holes M. In the outer peripheral region A, in the head width direction regions on both sides, more than 80% of the total number of hair implantation holes are hair implantation holes S. In the aforementioned lateral region B, more than 80% of the total number of hair implantation holes are hair implantation holes M, and the angle between the minor axis of the hair implantation hole M and the length direction of the head portion is less than 45°. The toothbrush is characterized in that, in the central region C, 80% or more of the total number of bristle holes are bristle holes L, and the angle between the short axis of the bristle holes L and the length direction of the head is less than 45°.

2. The toothbrush according to claim 1, characterized in that the bristle implantation holes M and L are substantially elliptical, including elliptical, track-shaped, egg-shaped, olive-shaped, and shapes in which the two radii of the minor axis of these shapes are of different lengths, shapes in which the major axis of these shapes is curved, and shapes in which the two radii of the minor axis of these shapes are of different lengths and the major axis is curved.

3. The total number of hair implantation holes in the central region C is 4 to 30, and they are formed in a single row extending along the length of the head portion, and the hair implantation holes L in the central region C are all the same shape. The toothbrush according to claim 1 or 2, wherein bristle holes L may be present at the top and bottom of the bristle surface of the outer peripheral region A, and if bristle holes L are present, the bristle holes L are the same shape as the bristle holes L of the central region C and are located on the extension of the row of bristle holes of the central region C.

4. The toothbrush according to claim 2, characterized in that the shape of the bristle-planting holes L is such that the long axis is curved, or the two radii of the short axis are different and the long axis is curved, and the angle between the short axis direction of the bristle-planting holes L and the length direction of the head is less than 10°.

5. In the central region C, there is a point P that may be located at the midpoint of the central region C in the length direction of the head, in the row of hair implantation holes extending along the length direction of the head. The toothbrush according to claim 4, characterized in that the curved protrusions of the bristle holes L located between point P and the top of the bristle surface are directed toward the top of the bristle surface, and the curved protrusions of the bristle holes L located between point P and the bottom of the bristle surface are directed toward the bottom of the bristle surface.

6. The toothbrush according to claim 5, characterized in that, with the exception of the bristle implantation hole located at point P, all bristle implantation holes in the central region C are bristle implantation holes L, each of the bristle implantation holes L has the same shape and size, and the angle between the short axis direction of the bristle implantation hole L and the length direction of the head portion is 3° or less in all cases.

7. The toothbrush according to claim 1 or 2, characterized in that, in the lateral region B, the shape of each of the bristle holes M is the same, and the angle between the short axis of the bristle holes M and the length direction of the head portion is 5° or more.

8. The toothbrush according to claim 1 or 2, characterized in that the total number of bristle implantation holes in one of the side regions B is 4 to 30, and all of these bristle implantation holes are bristle implantation holes M.

9. The toothbrush according to claim 8, characterized in that the bristle holes M are identical in shape and size, the angle between the minor axis of the bristle holes M and the length direction of the head is the same, and the two side regions B are symmetrical with respect to the center line in the width direction of the head.

10. The toothbrush according to claim 1 or 2, characterized in that the total number of bristle implantation holes in the outer peripheral region A is 10 to 50, the shape of the bristle implantation holes S in the outer peripheral region A is substantially circular, there are 8 or more of them, and the size of the bristle implantation holes S is the same.

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