JP2003144230A - Toothbrush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toothbrush wherein the bristle tips are easy to enter interdental sections to remove bacterial plaque, the cleaning efficiency is high, and there exists no possibility of damaging the gingiva. SOLUTION: For this toothbrush, a plurality of bristles are flocked on a tooth brush main body. In such a toothbrush, the bristle 12 is formed in such a manner that a section having a larger diameter than the diameter of the root section may not be located on the distal end side, and the bristle 12 may form a straight shape or a tapered shape wherein the distal end section has a smaller diameter than the root section. Such a bristle 12 is used for this toothbrush. Then, the shape of the distal end section 12b of the bristle 12 is formed into a curved surface shape such as a semispherical shape, and at least the distal end section 12b is formed into a smooth surface.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a toothbrush.

[0002]

2. Description of the Related Art A toothbrush is formed by implanting a plurality of bristles (brush bristles) in a toothbrush body. The bristles are generally made of nylon or the like, and have a diameter of about 200 μm and a length of about 10 mm. A plurality of the bristles are bundled, and the bristles are planted in tuft holes formed in the head member.

In the brushing of the oral cavity with a toothbrush, both the scraping method and the bath method brush both the tooth surface and the gingiva. Therefore, it is required that the bristles have a rigidity to surely remove dirt on the tooth surface and do not damage the gingiva (which is a soft tissue as compared with the tooth).

[0004]

On the other hand, there are many documents in which the shape of the bristle tip is designed (Japanese Patent Laid-Open No. 2001-120357,
JP 2001-120358, JP 2001-169828, JP 2000-11447,
JP-A-2000-23746, JP-A-2000-270928, etc.).

However, in the conventional toothbrush, even when the bristle tip is rounded, when the tip portion of the bristle is enlarged and observed, irregularities of several μm or more are observed. In such a toothbrush, excessive brushing causes damage to the gingiva. In other words, these toothbrushes do not have a smooth surface and therefore have a large number of edges at their tips, and these edges are caught on the gingiva, increasing frictional force and causing gingival damage. This phenomenon is similar to the edge effect described as the anti-skid effect of studless tires.

On the other hand, in order to remove the irregularities or edges,
There is one in which the tip of the hair is smoothly processed by heat melting. However, in such a bristle, the tip diameter becomes large, making it difficult for the bristle to enter the interdental part and causing less damage to the gingiva, but it may cause periodontal disease or tooth decay, Dust is difficult to clean.

On the other hand, in the case where the tip of the hair is processed so as to be easily inserted into the gap, the tip of the hair may be uneven or the shape of the tip may be sharp as in the above case, which may cause gingival damage. . Moreover, if the tip is too thin, the cleaning effect is low.

An object of the present invention is to eliminate the above-mentioned problems, and to provide a toothbrush which has rigidity to surely remove dirt on the tooth surface and which does not damage the gums. That is.

[0009]

A toothbrush according to the present invention is a toothbrush in which a plurality of bristles are planted on a toothbrush main body, and at least 10% of all bristles have a tip surface having a smooth convex curved surface. The maximum diameter of the bristle portion having this convex curved surface shape is substantially the same as or smaller than the diameter of the root portion of the bristle.

Another aspect of the present invention is the toothbrush,
A toothpaste set comprising a toothpaste containing no solid matter having a particle size of 10 μm or more.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The inventor of the present invention, as a result of intensive studies in view of the problems of the above-mentioned prior art, has found that the shape of a toothbrush and the shape thereof are important in smoothness of the tips of the bristles in contact with the gingiva. . That is, it was discovered that a toothbrush having a high cleaning effect and less gingival damage is designed by combining a specific shape of the bristle tip and a surface texture.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

1 to 3 show an embodiment of the toothbrush according to the present invention. More specifically, FIG. 1 is a plan view of this embodiment, FIG. 2 is a perspective view showing tufts, and FIG. 3 is a detailed view of the bristles.

As shown in these figures, this toothbrush is obtained by bristling a plurality of bristles 12 on the toothbrush main body 10, and at least 10% of all the bristles have a smooth tip 12b. Bristle portion 1 having a convex curved surface shape and having this convex curved surface shape
The maximum diameter d of 2b is substantially the same as or smaller than the diameter of the bristle root 12a.

The bristles having a convex curved surface whose surface is smooth are preferably 20% or more of all bristles,
It is more preferably 30% or more, further preferably 40% or more.

Here, the smooth surface is provided over a range of 0.1% or more (preferably 0.5% or more) of bristle bristle length from the bristle apex 12c,
The surface roughness is set to 1 μm or less. Surface roughness is defined by arithmetic mean roughness (Ra) (JIS B 0601-1
See 994 JIS B 0031-1994). This arithmetic mean roughness (R
In a), a filtered waviness curve of a bristle curved surface is created, and the surface roughness is calculated from a line (average line of roughness curves) obtained by replacing this with a straight line.

The vertical cross section of the tip portion 12b preferably further has a shape represented by the following equation.

[0018]

[Equation 2] However, as shown in FIG. 3C, the variable x represents the distance from the bristle center 12d in the bristle diameter direction to the bristle surface, and the variable y is the convex curved surface starting position in the bristle height direction. 12e represents the distance from the bristle surface.

When the bristle has a circular cross-sectional shape, for example, the parameter a is the convex curved surface starting position 12
The cross-sectional radius at e is represented, and the parameter b is the distance from the convex curved surface starting position 12e to the apex 12c. Further, the parameter n represents how the curved surface bends, as shown in FIG. That is, in FIG. 3C, the upper curve represents the cross section of the curved surface when n = 2, and the lower curve represents n =
The cross section of the curved surface at the time of 1.5 is shown. The parameter a preferably has a value in the range of 10 to 1000 μm, and more preferably has a value in the range of 50 to 500 μm. Further, the parameter b preferably has a value in the range of 5 to 1000 μm, and more preferably has a value in the range of 25 to 500 μm. Further, the parameter n preferably has a value in the range of 1.1 to 10, and 1.2 to
More preferably it has a value in the range of 5.

The above equation (1) is expressed by x ⁿ / a ⁿ + y ⁿ / b ⁿ = 1
Is an equation solved for y.

The vertical cross-sectional shape of the convex curved surface of the bristles does not have to be exactly represented by the curve of the above formula (1). For example, as shown by C1 in FIG. 7, the surface may have smooth irregularities with respect to the curve C0 represented by the formula (1) within a range in which the purpose and effect of this bristle can be achieved. . Further, this smooth unevenness has a curve C2 in which at least one parameter a, b, n has a parameter value smaller by 30% (more preferably 20%) with respect to the curve C0 represented by the formula (1), At least one parameter a, b, n is 30% (more preferably 20)
%) Has a size such that the curve C1 is located between the curve C3 and the curve C3 having a larger parameter value.

Further, the lower end position (position where polishing starts) 12e of the smooth surface 12b does not have to be the same height over the entire bristle periphery (see FIG. 8). In this case, for example, a line perpendicular to the bristle implanting direction is drawn from a position (polishing start position) 107 closer to the tip in the cross section, and a portion above the line has the above-described shape (that is, a curve of the formula 1). Or have a shape within the range of curves C2 and C3 of FIG. 7).

With the above construction, the toothbrush of this embodiment does not damage the gingiva made of soft tissue even when pressed relatively strongly against the tooth during brushing, and reliably removes dirt on the tooth made of hard tissue. You can do it.

The maximum diameter d of the bristle portion 12b having the convex curved surface shape is smaller than the diameter of the bristle root portion 12a. For example, if the diameter of the bristle root portion 12a is 20
In the case of 0 μm, the maximum diameter d is smaller than 200 μm.

As a result, when brushing teeth, the bristle 12
Is reliably inserted between the teeth, and plaque and the like between the teeth can be reliably removed.

The diameter d of the tip portion 12b is preferably larger than 1/100 of the bristle bristle length. For example, when the bristle hair length is 10 mm, the tip portion 12b is
The diameter is preferably larger than 0.1 mm (100 μm).

As a result, the bristle 12 has a strength not less than a predetermined value and can reliably remove plaque and the like.

The smooth tip portion 12b has a surface roughness of 1 μm or less.

The details are as follows.

A plurality of tuft holes 11 are formed in the head portion 10 of the toothbrush at a predetermined interval. Bristle 12 made of nylon, polyester or the like is planted in each of the tuft holes 11 to form tufts (hair bundles) 1.
Make up three.

The bristle 12 has a bristle diameter of 2
The hair length is set to about 100 μm and the hair length is set to about 10 mm. The bristle tip side does not have a portion having a diameter larger than the diameter of the root portion 12a, and has a substantially straight shape (cylindrical shape).

Further, as shown in FIGS. 3 (a) and 3 (b), the tip portion 12b has a convex curved surface shape such as a hemisphere, and the tip surface is smoothed by an appropriate smoothing process. There is.

This smooth surface is provided over the range of 0.5% or more of the bristle bristle length from the apex 12c. For example, when the bristle bristle length is 10 mm, the smooth surface extends from the apex 12c to a length range of 0.5 mm (500 μm) or more. As described above, the surface roughness of the smooth surface is 1
μm or less.

The smoothing treatment is carried out by wet polishing using ultrafine sandpaper (No. 1200 or above) for mirror finishing, melt softening by blowing hot air on the tips of the hair, or hydrolysis using an alkaline liquid. It can be carried out. By the smoothing treatment, the tips of the hairs after cutting can be rounded into hemispheres.

FIG. 4 shows the operation of this toothbrush.

As shown in FIG. 3A, the bristle 12
Since the tip shape of is a convex curved surface like a hemisphere, the gingiva is elastically deformed following the tip shape of the bristle 12 during brushing. Therefore, the tips of the hairs and the gums are in surface contact with each other, and a layered lubricating liquid film of the dentifrice is stably formed between the tips of the hairs and the gums. The tip portion 12b has a smooth surface with a surface roughness of 1 μm or less. Therefore, when used in combination with a dentifrice having an appropriate viscoelasticity, the friction between the tips of the hair and the gingiva can be significantly reduced, and the gingival protection effect can be greatly improved.

For example, an ordinary toothpaste is used and a toothbrush is moved at a constant linear velocity (1
It was confirmed that the friction force is about 270 gf in the toothbrush having the conventional bristles when moving at a speed of (cm / sec), whereas the friction force is about 150 gf in the toothbrush of this embodiment.

Therefore, according to the toothbrush of this embodiment, the gums are not worn during brushing.

In summary, the toothbrush of this embodiment removes the edge of the conventional toothbrush to make a smooth surface contact with the gingival surface, and when the toothbrush is moved, a thin liquid film is formed between the gingiva and the toothbrush. The frictional force can be greatly reduced.

FIG. 4B shows a state of bristles and teeth when brushing teeth using this toothbrush. As shown in the figure, since the tooth surface is enamel and is hard, the tooth surface is not elastically deformed by the brushing pressure even when the tip of the tooth hits the tooth surface. Therefore, the tip of the tooth and the tooth surface are in point contact with each other (a lubricating liquid film is less likely to be formed between the tip of the tooth and the tooth surface), and the dirt on the tooth surface is satisfactorily removed.

The bristle of the toothbrush of this embodiment has a straight shape, and there is no portion on the tip end side having a diameter larger than the diameter of the root portion. Therefore, the tips of the hairs easily enter between the teeth,
The plaque between the teeth can be reliably removed. In addition, this bristle is made of nylon, polyester, etc., and has a diameter of about 200 μm, so the bristle tip has a sufficiently large rigidity (even for bristle 12 having a bristle length of about 10 mm) to reliably remove dirt on the tooth surface. You can do it.

FIG. 5 shows a modification of the bristles of FIG.

The bristle 12 has a tapered taper portion 12c whose tip side is gentle, and the tip portion 12b having a diameter slightly smaller than the diameter of the root portion 12a has a hemispherical curved surface shape. In this way, the tip shape is not only hemispherical but also semi-spheroidal,
Various curved surface shapes such as rounded surface shapes are possible.

Another embodiment of the present invention is a toothpaste set comprising the toothbrush and the dentifrice.

The dentifrice here has suitable viscoelasticity,
Does not contain a solid substance as an abrasive or has a particle size of 10μ
It is preferable to include only solids of m or less.

In this embodiment, by using the toothbrush and the dentifrice together, it is possible to reduce the friction between the gingiva and the toothbrush during brushing and to suppress the gingival damage. In addition, this makes it possible to maintain the shape of the bristle tips for a relatively long period of time, thereby extending the life of the toothbrush.

As can be understood from the above description, the toothbrush or toothpaste set of this embodiment has a portion having a diameter larger than the diameter of the root portion (having a straight shape or a tapered shape in which the tip portion has a smaller diameter than the root portion). A bristle not on the tip side is used, and the tip of the bristle has a smooth curved surface shape such as a hemisphere. Therefore, the tips of the hairs easily enter between the teeth, plaque can be removed and stains on the tooth surface can be effectively removed, and the gingiva is not damaged.

In particular, when used in combination with an agent having an appropriate viscoelasticity, the friction between the tips of the hair and the gingiva can be greatly reduced, and the effect of protecting the gingiva can be greatly improved. In addition, it does not contain a solid substance as an abrasive or has a particle size of 10 μm.
The combined use of the above solid-free agents can extend the life of the toothbrush.

[0049]

Example A nylon brush having a diameter of 200 μm and a bristle length of 10 mm was flocked to a toothbrush having a flocking hole diameter of 1.6 mm and a flocking portion of 4 columns and 7 rows. According to the conventional method of rounding the tips of the hair, the tips of the tips of the hair were rounded off with a water resistant paper # 400 (comparative example). Further, this toothbrush was subjected to intermediate finishing with water-resistant paper # 1200, and then mirror-finished successively with an alumina polishing film (Malteau) having a particle size of 3 microns and an alumina polishing film (Malteau) having a particle size of 0.3 (( Example). 6A and 6B show SEM enlarged photographs of Examples and Comparative Examples, respectively.

The toothbrush of this example exerted the above-mentioned action (see the above description relating to FIG. 4), but the toothbrush of the comparative example had a rough surface and did not exert the above-mentioned action. At that time, glycerin was used as the lubricant, and the frictional force was 1 in the example.
40 gf and 280 gf in the comparative example.

Further, using the above toothbrush, a usage survey was conducted on 20 subjects with gingivitis. The usage survey was conducted in a crossover style, randomly divided into 2 groups of 10 people each.

Table 1 shows the results of this investigation.

[0053]

[Table 1]

[0054]

As described above, according to the toothbrush of the present invention, the gingiva is not damaged, and
The dirt on the tooth surface can be reliably removed.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a toothbrush according to the present invention.

FIG. 2 is a perspective view showing a tuft of a toothbrush according to the present invention.

FIG. 3 (a) is a perspective view showing one embodiment of the bristle of the toothbrush according to the present invention, and FIG.
(C) is a cross-sectional view of the bristle.

FIG. 4 (a) is an explanatory view schematically showing the contact state between the bristle tips and the gingival surface of the toothbrush according to the present invention, and FIG.
FIG. 3 is an explanatory view schematically showing a contact state between a tooth tip and a tooth surface of a toothbrush according to the present invention.

FIG. 5 is an enlarged view showing another embodiment of the bristle of the toothbrush according to the present invention.

6 (a) and 6 (b) are SEMs of Examples and Comparative Examples.
Shows an enlarged copy.

FIG. 7 is an explanatory view showing an example of the cross-sectional shape of the embodiment of the bristle of the toothbrush according to the present invention.

FIG. 8 is an explanatory view showing an example of a cross-sectional shape of the embodiment of the bristle of the toothbrush according to the present invention.

[Explanation of symbols]

10 head 11 tuft holes 12 Bristle 12a root part 12b tip 13 tufts

Claims (6)

[Claims] 1. A toothbrush in which a plurality of bristles are planted in a toothbrush body, wherein at least one of all bristles is used.
A toothbrush in which the tip surface of 0% of bristles has a smooth convex curved surface shape, and the maximum diameter of the bristle portion having this convex curved surface shape is substantially the same as or smaller than the diameter of the bristle root portion. 2. The toothbrush according to claim 1, wherein the smooth surface is provided in a range of 0.1% or more of the bristle bristle length from the bristle apex, and the surface roughness is 1 μm or less. 3. The toothbrush according to claim 1, wherein a vertical cross-sectional shape of the convex curved surface is represented by the following formula. [Equation 1] However, the variable x represents the distance from the bristle center to the bristle surface in the bristle diameter direction, and the variable y
Represents the distance from the convex curved surface starting position in the bristle height direction to the bristle surface, and the parameter a
Has a value of 10 to 1000 μm, and the parameter b
Has a value in the range of 5 to 1000 μm and the parameter n
Has a value in the range 1.1 to 10. 4. The vertical cross-sectional shape of the convex curved surface is a, b, n.
The toothbrush according to claim 3, which is in a range represented by an equation in which at least one parameter is increased or decreased at a constant rate. 5. The toothbrush according to claim 1, wherein the diameter of the bristle portion having the convex curved surface shape is larger than 1/100 of the bristle bristle length. 6. A toothpaste set comprising the toothbrush according to claim 1 and a dentifrice containing no solid matter having a particle size of 10 μm or more.