JP7583590B2 - toothbrush - Google Patents

Description

The present invention relates to a toothbrush, and in particular to a toothbrush in which bristle bundles each consisting of a number of bristles are planted in a number of bristle planting holes formed in a bristle planting base.

Toothbrushes are formed by fixing tufts (hair bundles) consisting of multiple bristles bundled together into multiple bristles holes formed in the bristles' surface, for example, by driving a flat wire into the tufting holes or by fusing them with heat. Toothbrushes are designed with various ideas in terms of the arrangement of the bristles and the shape of the bristles' tips, so that they can efficiently brush appropriately for the type of tooth (front teeth, back teeth, etc.) and the part of the tooth (interdental area, tooth surface, cervical area, back of the tooth, etc.), effectively remove plaque, and provide a good feeling when brushing.

For example, wide-head toothbrushes have been developed that have a bristle base with a width of 13 mm or more, allowing multiple areas and teeth to be cleaned simultaneously (see, for example, Patent Document 1).

JP 2020-28794 A JP 2017-51515 A

In the wide-head toothbrush described in Cited Document 1, the width of the bristles base is wider, and the length of the bristles base in the direction of the central axis is also longer, which restricts the freedom of movement within the oral cavity, making it difficult to carefully brush specific areas, for example, the borders between the teeth and gums.

A toothbrush has also been disclosed in which the width of the bristle base and the length in the direction of the central axis of the bristle base are made the same, thereby increasing the degree of freedom of movement within the oral cavity, allowing the user to obtain an appropriate partial brushing effect by simply making a back-and-forth motion within the oral cavity (see, for example, Patent Document 2). However, even when using the toothbrush of Patent Document 2, it is difficult to carefully brush the area, particularly the area on the back side of the teeth where the teeth and gums meet.

The present invention relates to a toothbrush that can simultaneously clean multiple areas and teeth, and can also carefully brush the area behind the teeth, particularly the area between the teeth and gums.

The present invention is a toothbrush in which bristle bundles each consisting of a number of bristles are respectively planted in a number of bristle planting holes formed in a bristle planting base, and in the bristle planting region surrounded by an imaginary annular line formed by connecting the outer edges of the bristle planting holes arranged in the outermost peripheral portion, the maximum width in the width direction perpendicular to the central axis direction of the bristle planting base is 13 mm or more, and the ratio of the maximum length in the central axis direction of the bristle planting base to the maximum width in the width direction is in the range of 0.9 to 1.1, and the bristle planting base has a top view shape that includes a tapered curved portion that curves from both side portions in the width direction toward the tip while decreasing the radius of curvature when viewed from above the bristle planting base.

The toothbrush of the present invention allows you to clean multiple areas and teeth at the same time, and can also carefully brush the area behind the teeth, especially the area where the teeth and gums meet.

FIG. 1 is a side view of a toothbrush according to a preferred embodiment of the present invention. FIG. 2 is a side view of a main portion of a toothbrush according to a preferred embodiment of the present invention. FIG. 3 is a schematic plan view of a main portion of a toothbrush according to a preferred embodiment of the present invention. 4(a) to 4(c) are explanatory diagrams showing a state in which a toothbrush according to a preferred embodiment of the present invention is used.

As shown in Figs. 1 to 3, the toothbrush 10 according to a preferred embodiment of the present invention is constructed by implanting tufts 16a, 16b (see Fig. 2) each consisting of a bundle of bristles 17a, 17b in a plurality of implantation holes 15a, 15b (see Fig. 3) formed in the bristle implantation base 13 of the toothbrush body 11, which is composed of a gripping portion 12, a bristle implantation base 13, and a neck portion 14 connecting the two. The toothbrush 10 of this embodiment has a function for efficiently cleaning the boundary between the upper and lower teeth 20 and the gums 21 on the front side of the teeth 20 at the same time (see Fig. 4(a)), and also has a function for carefully brushing the boundary between the teeth 20 and the gums 21 on the back side of the teeth 20 (see Fig. 4(b)).

As shown in Figs. 1 to 3, the toothbrush 10 of this embodiment is a toothbrush in which bristle bundles 16a, 16b, each consisting of a bundle of bristles 17a, 17b, are respectively planted in a plurality of bristle planting holes 15a, 15b formed in the bristle planting base 13, and the maximum width B (see Fig. 3) in the bristle planting region 18 surrounded by an imaginary circular line S formed by connecting the outer edges of the bristle planting holes 15a arranged in the outermost peripheral portion, perpendicular to the central axis direction X of the bristle planting base 13 is 13 mm or more, and the ratio of the maximum length L in the central axis direction X of the bristle planting base 13 to the maximum width B in the bristle planting base 13 is in the range of 0.9 to 1.1, and the bristle planting base 13 has a top view shape including a tapered curved portion 13b that curves from both sides in the bristle planting base 13 in the lateral direction Y with a smaller radius of curvature toward the tip while being curved in the top view.

In addition, in this embodiment, the bristles 17a, 17b that make up the bristle bundles 16a, 16b are formed from tapered bristles with a tapered portion 17c whose cross-sectional area decreases toward the tip and whose diameter d at a position 1 mm from the tip is 0.05 mm or more (see Figure 2).

In this embodiment, the toothbrush body 11 can be formed using any commonly used synthetic resin, without any particular restrictions. For example, it is preferable to use one or more resins selected from polypropylene, polyacetal resin, polystyrene resin, polyethylene terephthalate resin, acrylonitrile butadiene styrene resin, cellulose propionate resin, polyarylate resin, polycarbonate resin, acrylonitrile styrene resin, polyester, polybutylene terephthalate, polytrimethylene terephthalate, and polycyclohexane dimethylene terephthalate.

The bristle base 13 constituting the tip of the toothbrush body 11 has a top view shape that includes a tapered curved portion 13b that curves from both sides toward the tip while decreasing the radius of curvature, and preferably has a top view shape that resembles a Reuleaux triangle with each corner curved as shown in FIG. 3. The flat bristle surface 13a arranged on the top side of the bristle base 13 has a plurality of bristle holes 15a, 15b that open into the bristle surface 13a and into which bristle bundles 16a, 16b are planted. The bristle base 13 is preferably formed so that its thickness t (see FIG. 2) is 2.0 to 4.0 mm. This reduces the overall bulk of the bristle portion (brush portion) even if the bristle base 13 has a wide head, making it possible to clean the teeth 20 and gums 21 without stress.

In this embodiment, as shown in FIG. 1, the toothbrush body 11 is preferably formed so that the bristle surface 13a arranged on the upper side of the bristle base 13 is aligned along a plane parallel to the central axis X' of the gripping portion 12, with a neck portion 14 interposed between the toothbrush body 11 and the gripping portion 12 and including a portion extending obliquely therebetween. The neck portion 14 of the toothbrush body 11 is preferably formed to have a considerable length, for example, about 50 to 70 mm.

Furthermore, in this embodiment, the gripping portion 12 is preferably provided with a gripping portion 12a at the end portion on the neck portion 14 side, which has a vertically elongated cross-sectional shape in which the vertical width perpendicular to the horizontal direction is longer than the horizontal width parallel to the hair planting surface 13a of the hair planting base 13, and which can be held from both sides with the thumb and index finger. The gripping portion 12a is preferably positioned on the side where the hair bundles 16a and 16b are erected, rather than a virtual extension line along the hair planting surface 13a of the hair planting base 13. The surface of the gripping portion 12a is preferably treated to have an anti-slip finish.

This makes it possible to thoroughly and carefully brush the area, especially the back side of the teeth 20, where the teeth 20 meet the gums 21.

In this embodiment, the tufting surface 13a of the tufting base 13 has a top view shape that resembles a Reuleaux triangle, and as shown in Fig. 3, 30 circular peripheral tufting holes 15a, each having a size of, for example, about φ1.4 mm, are formed in a ring shape along the outer periphery of the Reuleaux triangle (see the shaded circles in Fig. 3). In the inner portion surrounded by the multiple peripheral tufting holes 15a in the outer periphery, 19 circular inner tufting holes 15b, each having a size of, for example, about φ1.4 mm, are formed in a ring shape (see the open circles in Fig. 3).

The 30 outer peripheral bristle implantation holes 15a and the 19 inner bristle implantation holes 15b are arranged in 9 rows in the width direction Y of the bristle implantation table 13 at predetermined intervals in the central axis direction X on the bristle implantation surface 13a of the bristle implantation table 13, and are arranged in a staggered pattern with a 1/2 pitch shift in the central axis direction X in each adjacent row. By providing a plurality of bristle implantation holes 15a, 15b in a staggered pattern on the bristle implantation surface 13a of the bristle implantation table 13, a sufficient distance is maintained between adjacent bristle bundles 16a, 16b, preventing interference between the bristle bundles 16a, 16b, and enabling the bristle implantation holes 15a, 15b to flexibly follow the undulating tooth surface. Of these tufting holes 15a, 15b, the 30 tufting holes 15a located on the periphery have tufts of outer tufts 16a, and the 19 tufting holes 15b located on the inner side have tufts of inner tufts 16b, which are planted, for example, by a known method of driving in flat wires or by fusion planting.

The bristles 17a, 17b that make up the outer bristle bundle 16a planted in the outer bristle hole 15a and the inner bristle bundle 16b planted in the inner bristle hole 15b are preferably made of synthetic resin. As the synthetic resin that forms the bristles 17a, 17b, various known materials used for bristles can be used without any particular restrictions, such as polyamides such as nylon (registered trademark) and nylon 6-12, polyesters such as polybutylene terephthalate, polyolefins, etc.

In addition, in this embodiment, it is preferable that all of the bristles 17a, 17b constituting the multiple bristle bundles 16a, 16b are thin bristles with a root diameter at the base end (the opening of the bristle implantation hole) of 0.152 mm (6 mils) or less. It is even more preferable that the root diameter at the base end of all of the bristles 17a, 17b is 0.10 to 0.13 mm (4 to 5 mils). By making the root diameter at the base end of all of the bristles 17a, 17b 0.152 mm (6 mils) or less, harm to the gums is reduced, and it is possible to brush carefully and thoroughly, targeting the boundary between the teeth 20 and the gums 21.

Furthermore, in this embodiment, it is preferable that the root diameter at the base end of the bristles 17b constituting the inner bristle bundle 16b planted in the inner bristle implantation hole 15b, which is a bristle implantation hole located in the inner portion surrounded by the outer bristle implantation hole 15a, is smaller than the root diameter at the base end of the bristles 17a constituting the outer bristle bundle 16a planted in the outer bristle implantation hole 15a, which is a bristle implantation hole located in the outer portion of the bristle implantation region 18 surrounded by the virtual ring line S. This makes it possible to relatively reduce the rigidity of the bristles 17b in the inner portion, and to encase each tooth 20, so that the brush part (bristles) can be closely attached to the teeth 20 and gums 21.

Each of the bristle bundles 16a, 16b is preferably planted by the above-mentioned known bristle planting method so that the bristle length from the bristle planting surface 13a of the bristle planting base 13 is, for example, 7 to 12 mm. In this embodiment, as shown in FIG. 2, it is preferable that the bristle bundles 16a, 16b are planted so that, for example, the shortest bristle length h1 from the bristle planting surface 13a of the bristle planting base 13 is 8.3 mm and the longest bristle length h2 is 10.5 mm. In addition, in this embodiment, it is preferable that the imaginary brush surface formed by connecting the tips of the bristles 17a, 17b that make up the bristle bundles 16a, 16b has a μ-shaped three-dimensional wave-cut shape in which both end portions are cut out obliquely and the center portion is curved in a downward convex arc when viewed from the side opposite the width direction Y of the bristle planting base 13. As a result, with the toothbrush 10 of this embodiment, as shown in FIG. 4(c), the tips of the bristles 17a, 17b can reach the boundary between the back side of the molar 20' and the gums 21', making it easier to brush these areas.

In addition, in this embodiment, as described above, the bristles 17a, 17b that make up the bristle bundles 16a, 16b are formed of tapered bristles with a tapered portion 17c whose cross-sectional area decreases toward the tip and whose diameter d at a position 1 mm from the tip is 0.05 mm or more (see Figure 2). This makes it possible to thoroughly remove plaque even with thin bristles 17a, 17b whose root diameter is 0.152 mm (6 mils) or less.

The toothbrush 10 of this embodiment has a maximum width B (see FIG. 3) in the width direction Y perpendicular to the central axis direction X of the bristle base 13 of the bristle base 13, which is surrounded by a virtual annular line S formed by connecting the outer edges of the bristle holes 15a arranged in the outermost peripheral portion, of 13 mm or more, and the ratio of the maximum length L in the central axis direction X of the bristle base 13 to the maximum width B in the width direction Y is in the range of 0.9 to 1.1. The bristle base 13 also has a top view shape that approximates a Reuleaux triangle, including a tapered curved portion 13b at the tip, which curves from both sides toward the tip with a smaller radius of curvature.

The maximum width B of the bristle implantation area 18 in the bristle implantation surface 13a of the bristle implantation base 13 in the width direction Y is 13 mm or more, and the ratio of the maximum length L in the central axis direction X to the maximum width B in the width direction Y is in the range of 0.9 to 1.1, so that, as shown in FIG. 4(a), it is possible to simultaneously target the boundary areas between the teeth 20 and the gums 21 on the front sides of the upper and lower teeth 20 and carefully clean these boundary areas at once. From this perspective, it is more preferable that the maximum width B of the bristle implantation area 18 in the width direction Y is 13 to 19 mm, and even more preferable that it is 15 to 17 mm. From the same perspective, it is more preferable that the maximum length L in the central axis direction X in the bristle implantation area 18 is in the range of 13 to 19 mm, and even more preferable that it is in the range of 15 to 17 mm.

In addition, the bristle base 13 has a planar shape at its tip that includes a tapered curved portion 13b that curves with a smaller radius of curvature from both sides toward the tip, so that, as shown in FIG. 4(b), when brushing the boundary between the tooth 20 and the gums 21 on the back side of the tooth 20, the corners at the tip side of the bristle base 13 do not get in the way, and the peripheral bristle bundles 16a at the peripheral portion of the bristle implantation area 18 can be smoothly aligned along the boundary between the tooth 20 and the gums 21 on the back side of the tooth 20, making it possible to clean these boundary areas, especially on the back side of the tooth 20, more carefully.

Therefore, the toothbrush 10 of this embodiment makes it possible to efficiently clean multiple cleaning areas and teeth 20 at the same time, and also makes it possible to brush more carefully, particularly targeting the boundary between the teeth 20 and the gums 21 on the back side of the teeth 20.

The present invention is not limited to the above embodiment, and various modifications are possible. For example, the planar shape of the bristle base, which includes a tapered curved portion that curves from both sides with a smaller radius of curvature toward the tip, does not necessarily have to be a planar shape that approximates a Reuleaux triangle, and may be a planar shape that includes various other tapered curved portions. The bristles that make up the bristle bundle do not necessarily have to be tapered bristles that include a tapered portion whose cross-sectional area decreases toward the tip, and may be bristles with rounded tips, etc.

10 toothbrush 11 toothbrush body 12 gripping portion 12a knob portion 13 bristle base 13a bristle surface 13b tapered curved portion 14 neck portion 15a outer peripheral bristle implantation hole 15b inner peripheral bristle implantation hole 16a outer peripheral bristle bundle 16b inner bristle bundle 17a, 17b bristles 17c tapered portion 18 bristle implantation area 20 teeth 20' molars 21, 21' gums X central axis direction Y of bristle base width direction S of bristle base imaginary circular line

Claims (7)

A toothbrush in which bristle bundles each consisting of a plurality of bristles are respectively planted in a plurality of bristle planting holes formed in a bristle planting base,
In a hair implantation region surrounded by a virtual annular line formed by connecting the outer edges of the hair implantation holes arranged in the outermost peripheral portion, the maximum width in a width direction perpendicular to the central axis direction of the hair implantation base is 13 mm or more, and the ratio of the maximum length in the central axis direction of the hair implantation base to the maximum width in the width direction is in the range of 0.9 to 1.1,
The bristle base has a shape in top view that approximates a Reuleaux triangle with each corner curved, including a tapered curved portion that curves from both sides in the width direction of the bristle base toward the tip, with the radius of curvature decreasing when viewed from above. The toothbrush of claim 1, wherein an imaginary brush surface formed by the connected tips of the bristles that make up the bristle bundle has a shape in which, when viewed from the side opposite the width direction of the bristle base, both end portions are cut out at an angle and the central portion is curved in a convex arc toward the bristle base . The toothbrush according to claim 1 or 2, wherein the root diameter at the base end of all bristles constituting the multiple bristle bundles is 0.152 mm or less. The toothbrush according to any one of claims 1 to 3, wherein the root diameters at the base ends of all the bristles constituting the bristle bundles planted in the bristle implantation holes located in the inner portion surrounded by the bristle implantation holes in the outer periphery in the bristle implantation region surrounded by the imaginary annular line are smaller than the root diameters at the base ends of all the bristles constituting the bristle bundles planted in the bristle implantation holes located in the inner portion surrounded by the bristle implantation holes in the outer periphery. 5. The toothbrush according to claim 3, wherein all of the bristles constituting the bristle bundle are tapered bristles having a tapered portion whose cross-sectional area decreases toward the tip and whose diameter at a position 1 mm from the tip is 0.05 mm or more. The toothbrush according to any one of claims 1 to 5, wherein the thickness of the bristle base is 2.0 to 4.0 mm. The toothbrush according to any one of claims 1 to 6, wherein the bristle holes are arranged in a staggered pattern on the bristle base.