JP5491138B2 - toothbrush - Google Patents

Description

  The present invention relates to a toothbrush.

The toothbrush has a configuration in which a hair bundle obtained by bundling a plurality of bristles is implanted in a plurality of flock holes formed in a flocking table.
Regarding the size of the toothbrush hole of the toothbrush, in Patent Document 1, considering the comfort of hitting the gums, the area of the toothbrush flocking hole (cross-sectional area of the flocking hole) should be reduced to 0.635 to 1.131 mm ^2. Is described.
Patent Documents 2 and 3 disclose toothbrushes in which a flocking hole having a large inner diameter is formed at the center of the flocking table, and flocking holes having a small inner diameter are formed on both sides and the periphery thereof.

JP 2006-181174 A JP 2008-154808 A JP 2001-353025 A

As in Patent Document 1, if the cross-sectional area of the flock hole is reduced to make the hair bundle thinner, the insertion property of the hair bundle or bristle into the gingival sulcus (periodontal pocket) is improved, and the contact with the gingiva is also soft. Become. However, since the hair bundle is thin and the brushing pressure on the teeth is low, the feeling of cleaning and cleanability are reduced.
On the other hand, when the cross-sectional area of the flocked hole is increased, the hair bundle becomes thick, so that the brushing pressure on the smooth surface of the teeth increases and the cleaning performance improves, but the contact with the gums also increases, and the gums Insertability into the groove is also reduced.

  On the other hand, as in Patent Documents 2 and 3, if the cross-sectional area of the center flock hole is increased, the cleaning property to the smooth surface of the teeth by the hair bundle in the center region is improved. The inner diameter of the central flock hole is 2.0 to 2.8 mm, and even in Patent Document 3, the bundle diameter of the hair bundle arranged in the central portion is as thick as 1.8 to 2.8 mm. Since it is hard to bend and is tightly pinched, it becomes difficult to insert a small-diameter hair bundle implanted on the outside between the teeth, and the cleanability between the teeth is also lowered.

  Therefore, the present invention has good bristle insertion into the gingival sulcus, excellent gingival sulcus cleanability, cleanability of the tooth surface including the interdental portion, and a feeling of cleaning, and the bristle hitting the gingiva is also soft. It relates to providing a toothbrush.

The present invention is a toothbrush in which a bunch of bristles bundled with a plurality of bristles is planted in a plurality of flock holes formed on the flocking table, and the flocking table has a cross-sectional area of 1.0 to 1.6 mm. ² having a central region in which a plurality of central flock holes are formed, and an outer peripheral region in which a large number of outer flock holes having a cross-sectional area of 0.4 to 0.9 mm ² are formed. The toothbrush whose ratio of the sum total of the cross-sectional area of the outer periphery flock hole to the sum total of 2-10 is 2-10 is provided.

  The toothbrush of the present invention has good bristle insertion into the gingival crevice, excellent gingival crevice cleaning, cleaning of the tooth surface including the interdental area, and a feeling of cleaning, and soft bristles hitting the gingiva. .

It is a side view which shows one Embodiment of the toothbrush of this invention. It is a front view which shows the flock base vicinity of the toothbrush shown in FIG. It is a schematic cross section which shows a gingival sulcus vicinity. It is a figure which shows the flock hole of the toothbrush of Example 1 and the comparative example 5 used for evaluation of "the insertion property of a bristle to a gingival crevice". It is a figure which shows the gingival sulcus model used for evaluation of "insertability of a bristle to a gingival sulcus", (a) is a front view, (b) is the sectional view on the AA line of (a). It is a graph which shows the evaluation result of "the insertion property of a bristle to a gingival crevice". It is explanatory drawing for demonstrating the evaluation method of "cleanability of an interdental part" and "strength of the bristle hitting to a gum." It is a graph which shows the simulation result about the toothbrush of an Example. It is a graph which shows the simulation result about the toothbrush of a comparative example.

The present invention will be described below based on preferred embodiments with reference to the drawings.
As shown in FIG. 1, a toothbrush 1 according to an embodiment of the present invention includes a brush unit 2 in which a plurality of hair bundles 22 in which a plurality of bristles are bundled are arranged on a hair transplant table 21. Has a handle portion 3 that is a portion of the brush portion 2 and a neck portion 4 that connects the brush portion 2 and the handle portion 3.

As shown in FIG. 2, the flocking table 21 in the present embodiment has a central region 23 in which a plurality of central flocking holes 24 having a cross-sectional area of 1.0 to 1.6 mm ² are formed, and a cross-sectional area of 0.4 to 1. And an outer peripheral region 26 in which a large number of outer peripheral flock holes 27 of 0 mm ² are formed.
The central region 23 is surrounded by an outer peripheral region 26, and is surrounded by the front and rear and left and right of the central region 23 in the longitudinal direction of the flocking table 21 (direction corresponding to the longitudinal direction of the toothbrush 1, the X direction in FIG. 2). Region 26 exists. The cross-sectional area of the flock hole 24 (27) in the present invention is the area of the flock hole 24 (27) on the surface 21a of the flocking table. In addition, when flocked by a flat line, the area shaved by the flat line in the opening of the flock hole is not included in the cross-sectional area of the flock hole.

  As shown in FIG. 2, the central region 23 in the present embodiment is formed in a substantially central portion in each of the longitudinal direction (X direction) and the width direction (Y direction) of the flocking table 21, and has a plurality of centers. The flocking hole 24 has a flocking hole row formed in series in the X direction. The outer peripheral region 26 has an annular flocked hole group in which outer peripheral flocked holes 27 are arranged in a ring shape, and the annular flocked hole group surrounds the central region 23. The outer peripheral flock hole 27 in the outer peripheral region 26 preferably surrounds the central region 23 in a single or double manner. The central region 23 may be formed so as to be biased forward or rearward from the central portion in the longitudinal direction (X direction) of the flocking table 21 while being surrounded by the outer peripheral flocking hole 27.

The cross-sectional area of the central flock hole 24 existing in the central region 23 is 1.0 to 1.6 mm ² .
By setting the cross-sectional area of the flock hole in the central region 23 to be 1.0 mm ² or more, a sufficient brushing pressure can be secured against the tooth surface and between the teeth, and a feeling of being firmly polished (clean feeling) It becomes easy to feel. In addition, the removal performance of plaque and dirt attached to the teeth is excellent.
On the other hand, when the cross-sectional area of the flock hole in the central region 23 is 1.6 mm ² or less, the cleanability of the interdental portion by the hair bundle of the central region 23 and the cleanability of the gingival sulcus by the hair bundle of the outer peripheral region 26 are improved. To do. That is, it is prevented that the hair bundle in the central region 23 comes into contact with the tooth surface and becomes difficult to enter the interdental portion, and the hair bundle or bristle in the outer peripheral region 26 does not easily enter the gingival crevice. Excellent bristle insertion into interdental and gingival sulcus.

The cross-sectional area of the central flock hole 24 in the central region 23 ensures a constant cleaning pressure for the entire tooth surface and between the teeth, and cleaning to the gingiva while having good insertion between the teeth and the gingival crevice. The cross-sectional area of the central flock hole 24 is preferably 1.1 to 1.5 mm ² , more preferably 1.2 to 1 from the viewpoint of suppressing pressure and achieving both a soft feel to the gingiva and a cleanability. 4 mm ² .

  The number of central flock holes 24 existing in the central region 23 (5 in the example shown in FIG. 2) is not particularly limited, but can be, for example, 2 to 10, preferably 3 to 7, More preferably, it is 4-6.

In brushing with a toothbrush, the hair bundle planted in the outer peripheral flock hole 27 existing in the outer peripheral region 26 is easily inserted into the gingival sulcus. The cross-sectional area of the outer flocked hole 27 in the outer peripheral region 26 makes it easy to insert the hair bundle planted in the outer flocked hole 27 into the gingival sulcus, softens the contact with the gingiva, and between the interdental portion and the tooth surface. from the viewpoint of the cleaning property and good, it is 0.4 to 1.0 mm ^2, more preferably 0.5～0.9Mm ^2, more preferably from 0.6 to 0.8 mm ^2.

The number of outer peripheral flock holes 27 existing in the outer peripheral region 26 (43 in the example shown in FIG. 2) is not particularly limited, but may be, for example, 32 to 50, preferably 38 to 48, More preferably, it is 40-46.
The center and outer periphery flocking holes 24 and 27 in this embodiment are both formed in a cylindrical shape having one end opened on the surface 21a of the flocking table. The cross-sectional area of the flocked hole is the area of the flocked holes 24 and 27 on the surface 21a of the flocking table, and is the same as the cross-sectional area of the cylindrical portions of the flocked holes 24 and 27. In this embodiment, the cross-sectional shape of the central flocking hole 24 is oval, and the cross-sectional shape of the outer flocking hole 27 is circular.

  The average ratio (b / a) of the individual cross-sectional area (b) of the outer peripheral flock hole 27 to the average of the individual cross-sectional area (a) of the central flock hole 24 is preferably 0.4 to 0.8. More preferably, it is 0.5-0.7.

Further, the ratio (S2 / S1) of the total cross-sectional area (S2) of the outer peripheral flock hole 27 to the total cross-sectional area (S1) of the central flock hole 24 is the hair planted in the central flock hole 24 and the outer flock hole 27. From the point of obtaining a constant cleaning pressure for the whole bundle, it is 2 to 10, preferably 3.5 to 9, more preferably 3.7 to 7, and particularly preferably 4 to 6.
Sum of the cross-sectional area of the central plant pores 24 (S1) is preferably 2～16Mm ^2, more preferably 3.3~10.5mm ^2, 4.8~8.4mm ² is more preferable.
Sum of the cross-sectional area of the outer peripheral bristle holes 27 (S2) is preferably 12.8～50Mm ^2, more preferably 19~43.2mm ^2, 24~36.8mm ² is more preferable.

In the flocked holes 24 and 27 in the toothbrush 1, a bristles 22 made of bristles of the number corresponding to the cross-sectional area of the flocked holes is inserted and fixed.
The bristle that constitutes the hair bundle is made of a synthetic resin. As the synthetic resin of bristle, various resins conventionally used in bristle can be used without particular limitation, and examples thereof include polyamides such as nylon (registered trademark) and nylon 6, polyesters such as polybutylene terephthalate, and polyolefins. It is done.
The diameter of the bristle is, for example, 150 to 250 μm, preferably 170 to 220 μm, more preferably 180 to 200 μm. The thickness of the bristle may be different between the central flock hole 24 and the outer flock hole 27. However, in the examples and comparative examples described later, the flock of the central flock hole 24 and the follicle of the outer flock hole 27 Thus, the bristle having the same thickness and the same material at the opening of the flock hole is used.

The bristle which comprises the hair | bristle bundle 22 planted by the center flock hole 24 becomes like this. Preferably it is 25-45, More preferably, it is 26-40, More preferably, it is 28-37. Each is planted by a known method of fusing.
The hair bundles 22 planted in the outer perforated hole 27 are preferably composed of 13 to 25, more preferably 14 to 21 bristle, and are each fused by heat by a known method. It has been planted.

  Various known methods can be used as the method of planting the hair bundle, such as (1) a method of driving the hair bundle by folding it in a flat line, or (2) heating one end of the hair bundle. A method of injecting a molten resin into a mold in which the molten mass is arranged and then injecting and forming a flocking table; (3) bristles in the flocked hole of the flocked base having a flocked hole (through hole). A state in which the hair bundle is implanted through an insertion step of inserting the bundle, a thermal processing step of heating one end portion of the hair bundle protruding from the flock hole to form a molten lump, and a covering step of covering the molten lump A method for obtaining a flocking table or toothbrush can be used.

  The method of planting the hair bundle is to form a molten lump at one end of the hair bundle from the viewpoint of being able to efficiently and sufficiently fix the hair bundle in a small diameter flock hole or flock hole and having an excellent appearance. The fusion flocking including the methods (2) and (3) is preferable, and the method (3) is particularly preferable. Specific examples of the method (3) include the methods described in JP-A-9-182632 and JP-A-2003-310353. In the method described in JP-A-2003-310353, one end of the hair bundle is heated with a non-contact heat source such as a laser beam to form a molten lump, and the molten lump and the peripheral edge of the flock hole opening Are fused.

  The bristle that constitutes the hair bundle 22 is preferably a tapered bristle whose cross-sectional area and diameter decrease toward the hair tip. When the hair bundle of the outer peripheral flock hole 27 is composed of a taper bristle, it is possible to further improve the insertability into the gingival sulcus and the soft touch to the gingiva. In addition, by forming the hair bundle of the outer flock hole 27 and the central flock hole 24 from a taper bristle, the balance of the brushing pressure between the outer flock hole 27 and the central flock hole 24 is further improved, and the interdental and the entire tooth surface. Easy cleaning.

The average length of the bristle constituting the hair bundle 22 from the surface 21a of the flocking table can be, for example, 10 to 15 mm, preferably from the point of giving a soft touch to the gingiva and the insertion property between the teeth. 12-14 mm. Moreover, it is preferable that the average length of the taper part in a bristle shall be 6-10 mm, More preferably, it is 6-8 mm. The taper bristle formation method includes a mechanical treatment step of grinding or polishing the bristle tip, and a chemical treatment step of treating the bristle tip with a solvent capable of dissolving the resin constituting the bristle. And a method including a chemical treatment step after a mechanical treatment step of grinding or polishing the tip of a bristle, and the like, including a step by chemical treatment from the viewpoint of making the touch on the gums softer Is preferred.
Solvents capable of dissolving the resin constituting the bristle include, for example, when the bristle contains polyester, an alkaline aqueous solution such as sodium hydroxide and potassium hydroxide, and when the bristle contains polyamide, calcium chloride and methanol. And oleyl alcohol, ethylene glycol, and zinc chloride aqueous solution.

  Further, the filling rate of the hair bundle 22 into the flock hole (total cross-sectional area of the bristle / cross-sectional area of the flock hole) is preferably 0.6 to 0.85%, and more preferably 0.65 to 0.85%. .

  Moreover, it is preferable that the hair | bristle bundle of the center flocking hole 24 and the hair | bristle bundle of the outer periphery flocking hole 27 have the same height from the flocking base surface 21a. Here, the phrase “the heights are equal” includes not only the case where the heights are strictly equal but also the case where there is a slight deviation. For example, when the height of the hair bundle of the peripheral flock hole is within 92 to 108% of the height of the bunch of the central flock hole, it is included when the height is equal. More preferably, the height of the hair bundle of the outer flock hole is within 95 to 105% of the height of the hair bundle of the central flock hole. Furthermore, it is preferable that the height of the bristle and the hair bundle from the flocking table surface 21a is substantially uniform in terms of both cleanability and touch to the gingiva.

According to the toothbrush 1 of the present embodiment, the flocking table 21 includes a central region 23 in which a plurality of central flock holes with a cross-sectional area of 1.0 to 1.6 mm ² are formed, and a cross-sectional area of 0.4 to 1.0 mm. ^{2 and} an outer peripheral region 26 in which a large number of outer peripheral flock holes 27 are formed. The hair bundle 28 implanted in the outer peripheral region 26 is thin and easy to be inserted into the narrow gingival sulcus 5. Since it is not obstructed by the pulling of the hair bundle 25 implanted in the central region 23, the insertion property of the hair bundle 28 implanted in the outer peripheral region 26 into the gingival sulcus 5 is improved as shown in FIG. Are better. Moreover, although the bristle of the hair bundle 28 implanted in the outer peripheral area | region 26 becomes easy, since there is also a moderate stiffness, it is excellent also in the cleaning property of the gingival sulcus 5. FIG. For example, it is excellent also in the removal ability about the plaque 61 which arose in the tooth cake 51 collected in the gingival crevice 5 and the tooth 6 near the gingival crevice 5.

Further, the cross-sectional area of the central flock hole 24 in the central region 23 having a large cross-sectional area is less than 1.6 mm ² , and even if the hair bundle 25 planted in the central flock hole 24 hits the gingiva 7, the hit is made. Since it is easy, the user can comfortably brush his / her teeth without feeling uncomfortable. Further, since the hair bundle 25 planted in the center flocking hole 24 is thinner than the hair bundle formed in the center of the flocking table in Patent Documents 2 and 3, it is easy to be inserted deeply between the teeth, and the interdental cleaning property. Also excellent.
In addition, since the bristle of the hair bundle planted in the central region 23 hits the tooth surface moderately, the cleanability of both the central region 23 and the hair bundle implanted in the outer peripheral region 26 is good. The removal performance of dirt and the like adhering to the surface is also good, and a sufficient cleaning feeling and cleanability can be obtained.

  Although the preferred embodiment of the toothbrush of the present invention has been described above, the toothbrush of the present invention is not limited to the above-described embodiment, and can be appropriately changed as described below without departing from the spirit of the present invention. Is possible. For example, the shape of the tip of the bristle can be a normal round cut, a spherical shape, a tip crack shape, or the like.

In the embodiment described above, the outer flock hole 27 has a circular cross-sectional shape, but it may be oval, elliptical, pentagonal or the like instead of the circular cross-sectional shape. Further, the central flocking hole 24 may be a perfect circle, an ellipse, a pentagon, or the like instead of an oval shape.
Moreover, as long as the method of planting the hair bundle can be planted in close contact with the tuft hole, various methods can be employed. The bristle may be monofilament or multifilament. The toothbrush main body (the flocking base 21, the neck part 3, and the handle part 3) can be formed from, for example, a thermoplastic resin. Examples of the thermoplastic resin include polyolefins such as polypropylene, polyesters such as polycarbonate, polymethyl methacrylate, and polyethylene terephthalate, acrylonitrile-styrene copolymers, acrylonitrile-butadiene-styrene copolymers (ABS resins), and the like. A thermoplastic resin can be used alone or in a suitable manner.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not restrict | limited at all by description of a following example and a comparative example.

[Example 1]
The toothbrush of Example 1 has substantially the same configuration as that of the embodiment shown in FIGS. 1 and 2 described above, and a central flocking hole 24 and an outer flocking hole 27 are formed in the arrangement shown in FIG. As shown in the sections of “shape and number of flock holes” and “array diagram” in Table 1, the center flock hole has five flock holes having an oval cross-sectional shape, and the short axis of the oval Is 0.5 mm and the major axis is 1.6 mm. Moreover, as an outer periphery flocking hole, it has 43 flocking holes with a circular cross-sectional shape. “R0.5-1.6 × 5” in Table 1 indicates that there are five oblong or elliptical holes having a minor axis of 0.5 mm and a major axis of 1.6 mm, and “φ1. “0 × 43” indicates that there are 43 holes having a circular cross section of 1.0 mm in diameter.
In the toothbrush of Example 1, the total cross-sectional area (S1) of the central flock hole 24, the total cross-sectional area of the outer flock hole 27 (S2), the ratio of the total (S2 / S1), the flocked table surface (flocked surface) ) And bristle hair length (height from the flocking table surface) are shown in [Table 1].
A hair bundle was fixed to each flocked hole by fusion flocking. The bristle that forms the hair bundle is made of nylon having a circular cross section. In addition, the diameter of the bristle and the filling rate of the bristle with respect to each flock hole are shown in Table 1.

[Examples 2 to 4, Comparative Examples 1 to 5]
A toothbrush having the same configuration as in Example 1 except that the shape, arrangement, dimensions, bristle diameter, etc. of the flock holes are changed as shown in [Table 1]. In Examples 2 to 4 and Comparative Examples 1 to 3, the bristle hair bundle is fixed by fusion flocking, and in Comparative Examples 4 and 5, the bristle hair bundle is fixed to the flock hole using a flat wire. . The bristle of the example and the comparative example is a tapered bristle by chemical treatment, and the length of the taper is about 8 mm on average.

[Test Example 1]
For the toothbrushes of Examples 1 to 4 and Comparative Examples 1 to 4, “feeling of dirt removal between the teeth”, “feeling of dirt removal between the teeth and gums”, “feeling of insertion into the gingival crevice”, “to the gums” The “feeling of contact” and “overall feeling of wiping” were evaluated.
Five people were allowed to use each toothbrush, and the above items were evaluated according to the following evaluation criteria. As the evaluation for each toothbrush, the evaluation with the largest number of people among the five was adopted, and the results are shown in Table 2.

〔Evaluation criteria〕
Evaluation criteria for “feeling of dirt removal between teeth”, “feel of dirt removal between teeth and gums”, and “overall feeling of brushing” ◎: Very good ○: Good ×: Not good “Insertion into gingival crevice Evaluation criteria for "feel" ◎: Insert very well ○: Insert well ×: No insertion feeling Evaluation criteria for "feeling against gingiva" ◎: Soft ○: Slightly soft ×: Strong

[Test Example 2]
[Easy insertion into the gingival crevice of bristle]
A row of outer flock holes of Example 1 shown by R1 in FIG. 4A and a row of outer flock holes of Comparative Example 5 shown by R2 in FIG. Insertability was evaluated. As a model of the gap, as shown in FIG. 5, a first plate 81 made of a transparent acrylic plate and having a thickness of 3.5 mm is used as a tooth model, and a second plate 82 made of transparent acrylic and having a thickness of 2 mm is used. Used as a gingival model. The first plate 81 and the second plate 82 are fixed so that the positions of the upper end edges 81a, 82a are shifted by 5 mm and are parallel to each other, and a gap 83 is formed between the plates 81, 82 assuming a gingival groove. . The gap 83 was adjusted to 0.1 mm and 0.2 mm by the spacer 84 assuming a healthy person to a periodontal patient. The depth at which the tip of the bristle of the hair bundle reached (inserted distance) when the toothbrush having the hair bundle was applied only to the outer peripheral flock holes of Example 1 and Comparative Example 5 at an angle at which the hair bundle was inserted as deeply as possible. Was measured. The results are shown in FIG.
In Example 1 in which the diameter of the flocked hole is 1.0 mm, the difference from Comparative Example 5 in which the diameter of the flocked hole is 1.5 mm increases as the gap width (gap amount) decreases, and the gap is 0.1 mm. In this case, it is confirmed that Example 1 is inserted with a depth of 2.2 mm, and Comparative Example is inserted with a depth of 0.9 mm, and Example 1 is inserted into the gap more than twice as compared with Comparative Example 5. Is recognized.

[Test Example 3]
"Cleanability of the interdental part" and "Strength of bristle hitting the gingiva"
〔Evaluation method〕
An example using a cleaning surface assuming an interdental model and using a program that can simulate on a computer the frictional force applied to the cleaning surface when the cleaning surface is cleaned with a toothbrush And the performance of each toothbrush of a comparative example was evaluated.
In the above program, the horizontal direction is defined as the x-axis and the vertical upward direction is defined as the y-axis, and the model shown in FIG. Specifically, on the xy plane, ¼ arcs of radius R (set to 4 mm) are placed facing each other across the y axis, and the horizontal line extends from the apex of each arc in the positive and negative directions of the x axis. Extends indefinitely. A virtual brushed surface was obtained by extending this line segment infinitely in the z-axis direction orthogonal to both xy axes.
The toothbrush keeps the flocking table surface horizontal, the bristles face downward, and the longitudinal direction of the toothbrush is made to coincide with the x-axis. The brushing direction is the x-axis direction (the longitudinal direction of the toothbrush), and the deformation of the hair bundle occurs only on the xy plane.
The toothbrush was moved in the x-axis direction in a state where a certain load was applied vertically downward to the pedestal portion (the flocked pedestal portion) of the toothbrush. The load applied to the base portion of the toothbrush (set to 150 gf) was defined as the total amount of the load applied to the hair bundle. Moreover, the bristle bundle of the toothbrush shall incline in the direction shown to FIG.7 (b) and (c) according to the moving direction of a toothbrush.

The toothbrush flocking specifications and brushing conditions were input as calculation conditions, and the frictional force at the tips of the bristles when the above virtual wiping surface was wiped with a toothbrush was simulated. In this simulation, the hairbrush specifications for the toothbrush include the length of the bristles (length from the flocking table), the diameter of the bristles constituting each bristles, the number of bristles, and the shape of the bristles (for example, the tip of the bristles is tapered) , Round shape, etc.), the shape of the cross section of the flocked hole constituting each hair bundle (for example, distinction between circular, oval, etc.), the size of the cross section of the flocked hole (diameter if the cross section is circular, In the case of an oval, the length of the long axis and the short axis), the number of each flock hole of each shape, and the material of the bristle is unified to nylon, and the Young's modulus is 2.0 × 10 ⁻⁹ Pa, As the brushing conditions, the friction coefficient of the brushed surface was calculated as 0.3. This program was based on a beam model, and was calculated by approximating the bending shape of the bristle as a straight line as shown in FIG.
As a result of this simulation, the sum of the frictional force when the bristles pass for all the hair bundles of the toothbrushes is plotted on the brushing surface for each part on the virtual brushing surface. And 9. The graphs shown in FIGS. 8 and 9 show only one side of both sides sandwiching the longitudinal center line of the pedestal (planting table).

FIG. 8A shows a simulation result for the toothbrush of the first embodiment. FIG. 8B shows a simulation result of the toothbrush of the second embodiment. FIG.8 (c) and FIG.8 (d) show the simulation result about the toothbrush of Example 3,4.
In the graphs shown in FIGS. 8 (a) to 8 (d), moderate frictional force is also applied to the portion corresponding to the interdental portion at the center in the left-right direction of the graph, particularly to the upper portion of the graph, which is the region where the outer peripheral flocking hole hits. In addition, a moderate and moderate frictional force is applied from the lower end of the graph corresponding to the longitudinal center line side of the flocking table to the upper end of the graph corresponding to the outer side in the width direction of the flocking table. .

  FIGS. 9A to 9E show simulation results for the toothbrushes of Comparative Examples 1 to 5. FIG.

  Table 3 shows the simulation results shown in FIGS. 8 and 9, the integrated value of the strength obtained by multiplying the strength of the friction pressure and the area ratio, the area ratio of the region of 0 to 3 gf where the friction force is weak, and the friction force The area ratio of the highest region (region where the frictional force is 18 gf or more) is shown. As shown in Table 3, in Examples 1 to 4, the area ratio of the low frictional force area was small, and the integrated value of the friction strength was higher than that of Comparative Examples 1 to 3. In Comparative Examples 4 and 5, there are few regions where the frictional force is weak, but there are many regions where the frictional force is strong, and the result is that the frictional force is strong, similar to the result of the test example 1 against the gingiva. On the other hand, Comparative Example 2 has a large area of the region where the frictional force is weak, while the region where the frictional force is strong extends to the interdental region as shown by the distribution of the frictional force in FIG. The evaluation results show that the gingival comfort is too strong.

DESCRIPTION OF SYMBOLS 1 Toothbrush 2 Brush part 21 Flocking table 21a Flocking table surface 23 Central region 24 Central flocking hole 25 Bristle 26 of the hair bundle planted in the central flocking hole Outer peripheral region 27 Outer flocking hole 28 Hair bundle planted in the outer flocking hole No bristle 3 handle 4 neck

Claims (6)

A toothbrush in which a bundle of hair bundled with a plurality of bristles is implanted in a plurality of flock holes formed in a flocking table,
The flocked block, cross-sectional area and a central area central flocking holes of 1.0～1.6Mm ² is formed with a plurality, is the cross-sectional area formed a number of outer peripheral bristles holes of 0.4 to 0.9 mm ² A peripheral region,
The toothbrush whose ratio of the sum total of the cross-sectional area of the said outer periphery flock hole is 2-10 with respect to the sum total of the cross-sectional area of the said center flock hole.   The toothbrush according to claim 1, wherein the hair bundle is implanted in the flock hole by a method that does not use a flat wire.   The toothbrush according to claim 1 or 2, wherein a filling ratio of bristle to the central flocking hole and the outer peripheral flocking hole is 0.6 to 0.85. The toothbrush according to any one of claims 1 to 3, wherein the bristle is a tapered bristle. Toothbrush according to any one of the middle planted bore tufts and the peripheral bristle holes tufts claim equal height from the flocked base surfaces and 1-4. The ratio (b / a) of the average of the cross-sectional area (b) of the outer peripheral flock hole to the average of the cross-sectional area (a) of the central flock hole is 0.4 to 0.8. The toothbrush according to item 1.