JP7461103B2 - toothbrush - Google Patents

Description

The present invention relates to a toothbrush.

Periodontal disease is said to be a national disease of the Japanese, and it has been reported that approximately 80% of people in their 30s show signs of periodontal disease. Periodontal disease is also known to be the most common cause of tooth loss. In order to prevent periodontal disease, plaque control using a toothbrush is important as a form of self-care.

Against this background, various toothbrushes have been proposed to improve the effectiveness of cleaning periodontal pockets. For example, the toothbrush disclosed in Patent Document 1 uses bristles with thin tips that can be easily inserted into periodontal pockets, and it has been reported that such thin bristles are effective in cleaning periodontal pockets. ing.

JP 2001-346630 A

However, bristles with fine tips have the problem that they are less effective at scraping off plaque than bristles with flat or hemispherical tips, and are less effective at cleaning tooth surfaces and occlusal surfaces. The present invention is designed to solve these problems, and aims to provide a toothbrush that makes it easy to insert bristles into periodontal pockets while at the same time providing sufficient cleaning effect on tooth surfaces and occlusal surfaces.

The toothbrush according to the present invention comprises a rod-shaped handle portion, a plate-shaped head portion connected to the axial tip of the handle portion, and a plurality of bristle bundles provided on one surface of the head portion, the plurality of bristle bundles comprising at least one row of a plurality of first bristle bundles aligned in the axial direction, at least two rows of a plurality of second bristle bundles aligned along the axial direction, at least a portion of which is arranged to sandwich the plurality of first bristle bundles in the width direction perpendicular to the axial direction, and at least two rows of a plurality of third bristle bundles aligned along the axial direction, at least a portion of which is arranged on the opposite side of the plurality of first bristle bundles in the width direction, sandwiching the plurality of second bristle bundles, the third bristle bundle, the second bristle bundle, and the first bristle bundle, the tip height from the head portion to the tip increases in the order of the third bristle bundle, the second bristle bundle, and the first bristle bundle, the tip of each bristle of the first bristle bundle is formed to be tapered and narrow, and the tip of at least some of the bristles of the second and third bristle bundles is formed to be flat or hemispherical.

According to this configuration, the tip of the first bristle bundle, which has the highest tip, is tapered, making it easier to insert this part into the periodontal pocket and scrape off plaque. In addition, the tip height of the second and third bristle bundles is adjusted so that the first bristle bundle is sandwiched between them and the overall shape is mountain-shaped. When the first bristle bundle is inserted into the periodontal pocket and the handle is tilted around the axis, the second and third bristle bundles can be easily brought into contact with the tooth surface or gums. When brushing in this state, at least some of the tips of the second and third bristle bundles are formed flat or hemispherical, making it easier to transmit force to the tooth surface or gums. Therefore, the cleaning power can be increased not only for the periodontal pocket but also for the tooth surface and gums.

In the above toothbrush, the tips of each of the second and third bristle bundles can be formed into a flat or hemispherical shape.

According to this configuration, force can be easily transmitted from the entire second and third hair bundles to the tooth surfaces and gums. Therefore, the cleaning power for tooth surfaces and gums can be further improved.

In the toothbrush described above, the third bristle bundle can be arranged next to the first bristle bundle at the tip end of the axial direction from the tip end toward the handle portion.

According to this configuration, the third bristle bundle, which is lower than the second bristle bundle, is disposed following the first bristle bundle on the tip side of the toothbrush, so that the third bristle bundle is lower than the second bristle bundle. The length of the higher part of the hair can be made longer. This increases the degree of freedom of movement of the first hair bundle, making it easier to insert the first hair bundle on the distal side into a periodontal pocket of a molar tooth, for example. Therefore, the cleaning power for periodontal pockets in areas that are difficult to brush, such as back teeth, can be increased.

In the above toothbrush, each bristles of each first bristle bundle has one end formed in a tapered shape and the other end formed in a flat or hemispherical shape, and the bristles are folded in half, and the folded portion is It is configured to be fixed to the head part, and in each of the first hair bundles, the height of the one end part of each hair from the head part is greater than the height of the other end part from the head part. The first end of each bristles may constitute a tip of the first bristles.

According to this configuration, each hair constituting the first hair bundle is folded in half, and only one end is tapered. Therefore, the number of tapered portions in each first hair bundle can be reduced, thereby making it easier to insert the hair into the periodontal pocket.

In the above toothbrush, the height of the other end of each of the bristles in each of the first bristles from the head is lower than the height of the bristles of each of the second bristles from the head. It can be configured as follows.

As a result, since the height of the other end of the first hair bundle is lower than the height of the hair of the second hair bundle, it is possible to suppress the other end from interfering with the movement of the one end. Freedom of movement can be increased. Therefore, the tapered one end can be easily inserted into the periodontal pocket.

In the above toothbrush, the difference between the height of the other end of the bristles of each of the first bristle bundles from the head part and the height of the bristles of each of the second bristle bundles from the head part is 2.0 mm. It can be within

As a result, the height of the other end of the first hair bundle and the height of the hair of the second hair bundle are equal to each other, so that the second hair bundle is placed on the tooth surface and gums in approximately the same area as the second hair bundle. The other end of one bristle bundle can also be brought into contact, and the cleaning effect of this part can be further enhanced.

In the above toothbrush, the difference between the height of the tip of the first bristle bundle and the height of the tip of the second bristle bundle can be 1.0 mm or more.

As a result, the length of the part of the first bristle bundle that is higher than the second bristle bundle is longer, allowing the tip of the first bristle bundle to move with greater freedom. This makes it easier to insert the first bristle bundle into the periodontal pocket.

In the toothbrush, the length of the head portion in the width direction can be 13 mm or more.

This makes it possible to increase the number of rows in the width direction of the hair bundles that can be arranged in the head section, allowing a wide area to be brushed at once.

In the toothbrush, the tip of the head portion can be formed into a triangular shape having a pair of sides that narrow toward the tip.

This makes it easier to insert the tip of the head into the back of the oral cavity, such as the back teeth, making it easier to brush the back teeth.

In the toothbrush described above, the bundle diameters of the first, second, and third bristle bundles can be made the same.

According to the toothbrush according to the present invention, the bristles can be easily inserted into periodontal pockets, and at the same time, a sufficient cleaning effect on tooth surfaces and occlusal surfaces can be obtained.

FIG. 1 is a plan view of a toothbrush according to an embodiment of the present invention. FIG. 2 is a side view of FIG. 1 . FIG. 2 is an enlarged view of FIG. FIG. 4 is a side view of FIG. 3; FIG. 4 is a front view of FIG. 3; FIG. 3 is a schematic diagram for explaining the hairs forming each hair bundle. FIG. 2 is a diagram illustrating the use of the toothbrush of FIG. 1.

One embodiment of the toothbrush according to the present invention will be described below with reference to the drawings. Fig. 1 is a plan view of the toothbrush according to this embodiment, and Fig. 2 is a side view of Fig. 1. For ease of explanation, the following description will be based on the directions in each figure. However, the present invention is not limited by these directional specifications.

<1. Overview of toothbrushes>
1 and 2, the toothbrush according to this embodiment comprises a rod-shaped handle portion 1, a plate-shaped head portion 2 integrally attached to the axial tip of the handle portion 1, and a plurality of bristle bundles 3 attached to the upper surface of the head portion 2. Each of the components will be described in detail below.

<1-1. Handle section>
The handle portion 1 is integrally formed with a rod-shaped base portion 11 to be held by hand and a connecting portion 12 that connects the base portion 11 to the head portion 2. The top and bottom surfaces of the tip of the base portion 11 are formed with placement portions 13 for placing fingers, and the placement portions 13 may be provided with unevenness, resin, rubber, etc. to prevent slipping.

The connecting portion 12 is formed into a rod shape that is thinner than the base portion 11 .

<1-2. Head section>
Next, the head portion 2 will be described with reference to Fig. 3. Fig. 3 is an enlarged view of Fig. 1. As shown in Fig. 3, the head portion 2 is formed in a plate shape, and is formed in an octagonal shape long in the axial direction in a plan view. For ease of explanation, the outline of the head portion 2 in a plan view is assumed to be composed of a tip edge 21, a first right side 22, a first left side 23, a second right side 24, a second left side 25, a third right side 26, and a third left side 27.

The tip edge 21 is the shortest edge of the head portion 2 and extends in the left-right direction. A first right side 22 and a first left side 23 are connected to both sides of the tip edge 21, and these extend away from each other as they move rearward from the tip edge 21. The second right side 24 and the second left side 25 are connected to the rear ends of the first right side 22 and the first left side 23, respectively, and extend parallel to each other in the front-rear direction. The third right side 26 and the third left side 27 are connected to the rear ends of the second right side 24 and the second left side 25, respectively. These extend closer to each other as they move rearward, and are connected to both sides of the connecting portion 12 of the handle portion 1.

The width W of the head portion 2 is not particularly limited as long as it does not cause any problems in handling in the oral cavity, but is preferably, for example, 10 mm or more and 20 mm or less, more preferably 13 mm or more and 17 mm or less, and particularly preferably 14 mm or more and 16 mm or less. As the width W of the head portion 2 increases, the number of rows of hair bundles that can be implanted increases, and thereby a larger area can be cleaned at one time. For example, five or more rows, preferably six or more rows of hair strands can be arranged on the upper surface of the head portion 2.

In addition, the upper surface of the head portion 2 is formed with a number of bristle implantation holes 28 into which the bristle bundles 3 described below are implanted (see FIG. 6).

The handle portion 1 and head portion 2 are integrally formed from a resin material such as plastic.

<1-3. Hair bundle>
Next, the hair bundle 3 will be described with reference to Figs. 4 to 6. Fig. 4 is a side view of Fig. 3, Fig. 5 is a front view of Fig. 3, and Fig. 6 is a schematic diagram for explaining the hairs constituting each hair bundle. In this embodiment, three types of hair bundles, namely, a first hair bundle 31, a second hair bundle 32, and a third hair bundle 33, are provided in multiple numbers and arranged to form a row in the front-rear direction. In Figs. 3 to 5, for the convenience of explanation, each type of hair bundle is colored, but this is for the convenience of explanation, and all the hair bundles can be the same color, such as white. Note that the hair bundles shown in Figs. 3 to 5 and 7 are merely schematic diagrams, and a state in which multiple hairs are bundled is shown as a rectangular hair bundle.

<1-3-1. First hair bundle>
3 to 5, the rows of the first bristle bundles 31 are provided in roughly two rows at the center in the width direction of the head portion 2, and each row extends from near the tip edge 21 to near the connecting portion 12 of the handle portion 1. However, only the third bristle bundle 31a from the tip, and the rearmost and second-to-rearmost bristle bundles 31b, 31c are in a single row.

As shown in the enlarged view of FIG. 5 and FIG. 6, the multiple bristles 310 constituting each first bristle bundle 31 are tapered such that one end 311 becomes thinner toward the tip, and the other end 312 is flat or semi-spherical. The multiple bristles 310 thus formed are bundled and folded in half. A known flat wire 4 is then attached to the folded portion, and this folded portion is driven into the bristles implantation hole 28 of the head portion 2 together with the flat wire 4. This fixes the first bristle bundle 31 to the head portion 2.

At this time, the first hair bundle 31 is fixed so that one end 311 of each hair 310 is higher than the other end 312. Therefore, the tip at the highest position of the first hair bundle 31 is formed by the tapered one end 311, and the flat other end 312 is arranged at a lower position. Here, the height L1 (tip height) of the first hair bundle 31 is the height from the top surface of the head part 2 to the tip of the tapered one end 311 of each hair 310. The height L1 of the first hair bundle 31 can be, for example, 10 to 15 mm, preferably 12 to 15 mm, and most preferably 13 to 14 mm. In addition, if there is variation in the height of the hairs 310 included in each first hair bundle 31, the average height of the hairs 310 is set to the height L1 of the first hair bundle 31. This point is the same for the second hair bundle 32 and the third hair bundle 33 described later. Furthermore, the number of bristles 310 contained in each first bristles bundle 31 is not particularly limited, but is preferably, for example, 20 to 60 bristles, and more preferably, 30 to 50 bristles. The number of bristles contained in the second bristles bundle 32 and the third bristles bundle 33 is also not particularly limited, but is preferably, for example, 10 to 50 bristles, and more preferably, 20 to 40 bristles. Note that the number of bristles referred to here is the number of bristles after the bristles are bent as described above and implanted in the head portion 2, that is, the number of bristles protruding from the head portion 2. This point is the same in other descriptions in this specification.

<1-3-2. Second hair bundle>
Next, the second hair bundle 32 will be explained. As shown in FIG. 3, one row of the second hair bundles 32 is arranged on each side of the first hair bundle 31. That is, they are arranged so that the first hair bundle 31 is sandwiched therebetween. The second hair bundle 32 closest to the tip is arranged to sandwich the third row of first hair bundles 31a from the front. Further, they are arranged up to both sides of the last first hair bundle 31c. As described above, in the first hair bundle 31, the third hair bundle 31a and the last two hair bundles 31b and 31c are in one row, so the second hair bundle 32 sandwiching this has a width near the center in the front-rear direction. It is arranged so that it bulges outward in the direction.

As shown in FIG. 6, the plurality of hairs 320 constituting the second hair bundle 32 have both ends flat or semispherical. The plurality of bristles 320 thus formed are bundled and folded in half. Then, like the first bristle bundle 31, it is driven into the tufting hole 28 of the head portion 2 together with the flat wire 4. However, each hair 320 constituting the second hair bundle 32 is equally folded in half and fixed to the head part 2 so that both ends are at the same height. Here, the height L2 (tip height) of the second bristle bundle 32 is defined as the height from the top surface of the head section 2 to the tips of both ends of each bristle 320.

The height L2 of the second bristle bundle 32 is lower than the first bristle bundle 31, and can be, for example, 8 to 13 mm, preferably 10 to 13 mm, and most preferably 11 to 12 mm. The difference in height from the first bristle bundle 31 (the difference between L1 and L2) is preferably 1 to 4 mm, more preferably 2 to 3 mm, and most preferably 1.5 to 2.5 mm.

The height L4 of the other end 312 of each hair 310 of the first hair bundle 31 is preferably within 2.0 mm of the height L2 of the second hair bundle 32, more preferably within 1.5 mm, and particularly preferably within 1.2 mm. In particular, it is preferable that the height L4 is within 2.0 mm of the height L2 of the second hair bundle 32 and is lower than the height L2 of the second hair bundle 32.

<1-3-3. Third hair bundle>
Next, the third hair bundle 33 will be described. As shown in Fig. 3, the rows formed by the third hair bundles 33 are arranged generally on either side of the second hair bundle 32, one row on each side. That is, they are arranged so as to sandwich the second hair bundle 32. However, the third hair bundle 33a on the most distal end side is arranged so as to sandwich the first hair bundles 31 in the second two rows from the front. Therefore, as shown in Fig. 4, in a side view, from the distal end, the third hair bundle 33a is arranged following the first hair bundle 31, and the second hair bundle 32 is arranged following this.

The third tuft of hair 33 is then arranged on both sides of the second tuft of hair 32, all the way up to both sides of the second tuft of hair 32 from the rearmost. Therefore, like the second tuft of hair 32, the third tuft of hair 33 is arranged so that the area near the center in the front-to-rear direction bulges outward in the width direction.

As a result, the first to third bristle bundles 31 to 33 are arranged in two rows with the first bristle bundle 31 at the very tip, and as shown in Figure 3, are arranged in a roughly triangular shape in plan view to match the shape of the area near the tip of the head unit 2. Furthermore, near the rear end of the head unit 2, the rearmost bristle bundles 3 are arranged in three rows. In other words, three bristle bundles are arranged: the first bristle bundle 31 and two second bristle bundles 32 sandwiching it. The multiple bristle bundles 3 arranged at the rear end are arranged in a roughly trapezoidal shape in plan view to match the shape of the area near the tip of the head unit 2.

As shown in FIG. 6, the multiple bristles 330 constituting the third bristles bundle 33 are formed with flat or hemispherical ends, similar to the second bristles bundle 32. Then, similar to the second bristles bundle 32, they are folded evenly in half and fixed to the head unit 2 so that both ends are at the same height. Here, the height L3 (tip height) of the third bristles bundle 33 is defined as the height from the top surface of the head unit 2 to the tips of both ends of each bristles 330.

The height L3 of the third hair bundle 33 is lower than the second hair bundle 32, and can be, for example, 7 to 12 mm, preferably 8 to 11 mm, and most preferably 9 to 10 mm. The difference in height with the first hair bundle 31 (difference between L1 and L3) is, for example, preferably 3 mm or more, most preferably 4 to 6 mm.

As described above, the first hair bundle 31, the second hair bundle 32, and the third hair bundle 33 are formed so that the height decreases in this order, and thereby, as shown in FIG. When viewed from the front, these hair bundles 3 are arranged to form a mountain shape. Table 1 below shows two examples of the height of each hair bundle 31 to 33, but this is just an example, and various heights other than these can be used.

The material constituting the bristles of each bristle bundle 31 is not particularly limited, and can be, for example, saturated polyester resin, nylon, etc. The diameter of the bristles 310, 320, 330 of each bristle bundle 31-33 and the bundle diameter of each bristle bundle 31-33 can be approximately the same. The diameter of each bristles 310, 320, 330 can be, for example, 0.12-0.25 mm. On the other hand, the bundle diameter of each bristle bundle 31-33 can be, for example, 0.5-2 mm. The shape of the bristle implantation hole 28 of each bristle bundle is not particularly limited, and can be, for example, a perfect circle, an ellipse, a polygon, etc.

<2. How to use a toothbrush＞
Next, a method of using the toothbrush formed as described above will be described with reference to FIG. 7. The height L1 of the first hair bundle 31 is the highest and is arranged at the center in the width direction. Since the tip of the first bristle bundle 31 is formed in a tapered shape, the bristle bundle 3 is brought into contact with the tooth so that this part is inserted into the periodontal pocket 51. To do this, as shown in FIG. 7, the handle portion 1 is rotated around the axis to tilt the hair bundle 3, and then brought into contact with the teeth for brushing. At this time, since the hair bundles 3 are arranged in a mountain shape when viewed from the front, when the first hair bundle 31 is arranged so as to be inserted into the periodontal pocket 51, the second and third hair bundles on one side in the width direction 32 and 33 are in contact with the tooth surface. Therefore, the periodontal pocket 51 and the tooth surface 52 can be cleaned. Furthermore, when cleaning the occlusal surface 53, the head portion 2 may be placed parallel to the occlusal surface 53 and the hair bundle 3 may be pressed while brushing.

<3. Features＞
According to the toothbrush according to the above embodiment, the following effects can be obtained.
(1) Since the tip of the highest first hair bundle 31 is tapered, this part can be easily inserted into the periodontal pocket 51, making it easier to scrape out plaque and dirt. . In addition, the height of the second hair bundle 32 and the third hair bundle 33 is adjusted so that the first hair bundle 31 is sandwiched between them and the whole has a mountain shape. When the handle portion 1 is tilted around the axis while the handle portion 1 is inserted into the holder, the second bristle bundle 32 and the third bristle bundle 33 can be easily brought into contact with the tooth surface 52. When brushing is performed in this state, the tip portions of the second bristle bundle 32 and the third bristle bundle 33 are formed in a flat or hemispherical shape, so that force is easily transmitted to the tooth surface 52. Also, when brushing the occlusal surface 53, force is easily transmitted by the second hair bundle 32 and the third hair bundle 33. Therefore, the cleaning power not only for the periodontal pocket 51 but also for the tooth surface 52 and the occlusal surface 53 can be increased.

(2) At the tip side of the head unit 2, the third bristle bundle 33a is arranged next to the first bristle bundle 31 from the tip side toward the handle unit 1 side. In other words, the third bristle bundle 33, which is lower than the second bristle bundle 32, is arranged next to the first bristle bundle 31, so that in this portion, the length of the portion of the first bristle bundle 31 that is higher than the other bristle bundles can be increased. This increases the degree of freedom of movement of the first bristle bundle 31, making it easier to insert the tip side (front side) of the first bristle bundle 31 into the periodontal pocket 51 of the back teeth, for example. Therefore, it is possible to increase the cleaning power for the periodontal pocket 51 of parts that are difficult to brush, such as the back teeth.

(3) The number of hairs contained in each hair bundle is not particularly limited, but for example, the first hair bundle 31 contains 20 to 60 hairs, and the second hair bundle 32 and the third hair bundle 33 contain 10 to 50 hairs. In the second hair bundle 32 and the third hair bundle 33, each hair 320, 330 is folded evenly in half so that both ends are aligned. Therefore, for example, if each hair bundle 32, 33 contains 10 hairs, since they are folded in half, the ends of the 20 hairs form the tips of the second and third hair bundles 32, 33.

On the other hand, the bristles 310 of the first bristle bundle 31 are also folded in half, but the height of the tapered end 311 is increased so that this end 311 constitutes the tip of the first bristle bundle 31. Therefore, the number of bristles constituting the tip of the first bristle bundle 31 is smaller than those of the second and third bristle bundles 32 and 33. Therefore, since the number of tapered bristles is smaller, it is easier to insert the bristles into the periodontal pocket 51.

(4) In the first bristle bundle 31, the height L4 of the other end portion 312 is adjusted to be approximately the same height as the second bristle bundle 32. The other end 312 of the first hair bundle 31 can also be brought into contact with approximately the same part as the part with which the bundle 32 comes into contact. In particular, one end 311 of the first bristle bundle 31 is formed into a tapered shape and is soft, so when brushing the tooth surface 52, it does not interfere with brushing by the other end 312 and the second bristle bundle 32. . Further, since the other end portion 312 and at least two rows of second bristle bundles 32 allow brushing to be performed over a wide range, the tooth surface 52 can be thoroughly brushed in the same range as a normal toothbrush. Therefore, the cleaning effect can be further enhanced.

4. Modifications
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. The following modified examples can be appropriately combined.

<4-1>
In the above embodiment, hair bundles 31 to 33 of three different heights are used, but the present invention is not limited to this, and four or more types of hair bundles of different heights may also be used. In this case as well, it is preferable to adjust the height of the hair bundle so that it becomes mountain-shaped as a whole when viewed from the front, and the height of the hair bundle decreases as it goes outward in the width direction. However, as described in the above embodiment, a third hair bundle 33 or a lower hair bundle may be placed adjacent to the first hair bundle 31 instead of the second hair bundle 32. That is, the hair strands do not need to be arranged in the order of height in the width direction as long as the hair strands are partially arranged.

<4-2>
There is no particular limitation on the number of bristle bundles 3. In the above embodiment, two rows of the first bristle bundles are provided, one row of the second bristle bundles 32 on each side of the first bristle bundles, and one row of the third bristle bundles 33 on each side of the second bristle bundles 32, but this is just one example, and the number of rows of each of the bristle bundles 31 to 33 can be changed as appropriate.

<4-3>
The number of hairs, the diameter of the hairs, and the bundle diameter of the hair bundles constituting each hair bundle 31 to 33 are not particularly limited, and may be all the same as in the above embodiment, or may be different. can. In particular, by making all hair bundles the same diameter, force can be applied uniformly to each hair bundle during brushing, and furthermore, it is easier to adjust the bundle diameter during manufacturing, which contributes to cost reduction. do. Furthermore, at least one of the hair bundles 31 to 33 may be colored so that the difference in height can be seen.

<4-4>
The method of implanting each of the bristle bundles 31 to 33 is not particularly limited. In the above embodiment, the bristles 310 of the first bristle bundle 31 are bent so that one end of the tapered shape is higher, but the position of the fold is not particularly limited as long as it does not interfere with the tapered portion. In addition, the other end 312 can be formed in a shape other than flat or hemispherical, for example, tapered.

The position of the folds in the second and third bristle bundles 32, 33 is not particularly limited, and the heights of both ends may be different. In addition, some ends of the bristles in the second and third bristle bundles 32, 33 may be formed into a shape other than flat or hemispherical, for example, tapered.

<4-5>
The shapes of the handle portion 1 and the head portion 2 are not particularly limited and can be changed as appropriate. For example, the shape of the head portion 2 (particularly the planar shape) can be changed as appropriate according to the desired arrangement of the hair bundles.

1 Handle part 2 Head part 3 Hair bundle 31 First hair bundle 310 Hair 311 One end part 312 Other end part 32 Second hair bundle 320 Hair 33 Third hair bundle 330 Hair

Claims (6)

A rod-shaped handle part,
a plate-shaped head portion connected to an axial tip portion of the handle portion;
a plurality of hair bundles provided on one surface of the head portion;
Equipped with
The plurality of hair bundles are
at least one row of a plurality of first hair bundles arranged in the axial direction;
At least two rows of a plurality of second hair bundles, at least a portion of which are arranged to sandwich the plurality of first hair bundles in a width direction perpendicular to the axial direction, and lined up along the axial direction;
In the width direction, at least a portion of the hair bundles are disposed on the opposite side of the plurality of first hair bundles with the plurality of second hair bundles in between, and are arranged in at least two rows along the axial direction. A third hair bundle,
Equipped with
The third hair bundle, the second hair bundle, and the first hair bundle are formed such that the height of the tip portion from the head portion to the tip portion increases in this order,
The tip of each hair of the first hair bundle is formed to be tapered and thin,
The tips of at least some of the hairs of the second and third hair bundles are formed into a flat or hemispherical shape,
Each hair of each first hair bundle has one end formed in a tapered shape and the other end formed in a flat or hemispherical shape,
The hair is folded in half and the folded part is fixed to the head part,
Each of the first hair bundles is configured such that the height of the one end of each hair from the head is higher than the height of the other end from the head,
One end of each of the hairs constitutes a tip of the hair of the first hair bundle,
The height of the other end of each of the hairs in each of the first hair bundles from the head part is configured to be lower than the height of the hairs of each of the second hair bundles from the head part. Ori,
Each hair of each of the second hair bundle and each of the third hair bundle has both ends formed into a flat or hemispherical shape, the hair is folded in half, and the folded part is fixed to the head part. configured,
In each of the second bristle bundles and each of the third bristle bundles, the heights of both end portions of each of the bristles from the head portion are approximately the same . The toothbrush according to claim 1, wherein the tips of all the bristles of the second and third bristle bundles are formed into a flat or hemispherical shape. 2. The third hair bundle is arranged so as to follow the first hair bundle in a side view from the front end side in the axial direction toward the handle portion side. The toothbrush according to 1 or 2. The difference between the height of the other end of the hair of each of the first hair bundles from the head part and the height of the hair of each of the second hair bundles from the head part is within 2.0 mm. The toothbrush according to any one of Items 1 to 3 . The toothbrush according to any one of claims 1 to 4 , wherein the difference between the tip height of the first bristle bundle and the tip height of the second bristle bundle is 1.0 mm or more. The tip of the head portion is
6. The toothbrush according to claim 1, which is formed to have a pair of side edges whose width narrows toward the tip.