TWI729082B - Toothbrush - Google Patents

Abstract

The present invention provides a toothbrush with more excellent cleaning power and more excellent feeling in use. A toothbrush (1), characterized in that it comprises a head (2), a neck (4) extending on the head (2), and a handle (6) extending on the neck (4) The handle body (10) of the head (2) is planted with hair bundles on the hair transplanted surface of the head (2), and the bending amount A of the head (2) and the neck (4) The product of the bending amount B is 0.8-10.

Description

toothbrush

The present invention relates to a toothbrush.

This application is based on Japanese Patent Application No. 2016-045368 filed in Japan on March 9, 2016 and claims priority, and the content is cited in this application.

When preventing dental caries and periodontal disease, it is important to remove plaque in the oral cavity by brushing the teeth with a toothbrush. Previously, various toothbrushes have been proposed in order to improve the effect of removing plaque. For example, by thinning the head of the toothbrush and thinning the neck, the toothbrush bristles can reach the depths of the molars (the throat side of the molars), which is difficult to reach with ordinary toothbrushes. Patent Document 1 describes a toothbrush with a thin head and excellent operability in the oral cavity.

On the other hand, for people living with periodontal disease and the like, it is important to remove the dirt of the periodontal pocket by brushing with a toothbrush, or to massage the gums. To remove dirt from the periodontal pocket or massage the gums, appropriate bending of the toothbrush bristles is required. To date, toothbrushes with dense bristles of fine diameter or toothbrushes using extremely fine bristles have been proposed.

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 7-143914

However, if only the head of the toothbrush is made thin in order to improve the cleaning power against the deep parts of the molars, etc., which are difficult to reach with a normal toothbrush, the bending strength of the head or the strength of the hair bundle falling off will decrease, and the quality of the toothbrush will decrease. . In addition, due to the thinning of the head, the head tends to bend and the hair bundles expand during use, which impairs the user's feeling of use. Therefore, there is a limit to making the head thinner.

In addition, by increasing the curvature of the toothbrush bristles, the contact feeling to the gums becomes better, and the feeling of use can be improved. However, if the curvature of the toothbrush bristles is too large, problems such as a decrease in the penetration of the toothbrush bristles into the periodontal pocket and a decrease in the cleaning power, or the increase in the branching of the bristles, the durability of the toothbrush decreases.

The present invention was made in view of the above circumstances, and its object is to provide a toothbrush that is more excellent in cleaning power and more comfortable in use.

The present invention has the following constitution.

[1] A toothbrush, characterized in that it comprises a handle body having a head, a neck extending on the head, and a handle extending on the neck, and planted on the hair grafting surface of the head The hair bundle is provided, and the product of the amount of curvature A of the head measured by the following method (α) and the amount of curvature B of the neck measured by the following method (β) ( A×B) is 0.8~10.

Method (α): the front of the shank in a state where the hair transplanted surface of the head faces upward in the vertical direction, and the position of the boundary between the head and the neck is fixed The height of the end is the reference height, and in the fixed state, with respect to the length of the long axis direction of the hair transplanting part in the head, 200g of 200g is hung at a position 10±3% from the tip of the hair transplanting part The weight is weighed, and the amount of displacement (in mm) of the height of the front end of the handle body from the reference height after 10 seconds is set as the bending amount A of the head.

Method (β): Make the tufted surface of the head face upward in the vertical direction, and use the height of the tip of the shank in a state where the position of the border between the neck and the shank is fixed as a reference Height, in the fixed state, relative to the length of the hair transplanting part in the head in the long axis direction, a 200g weight is hung on the position 50±3% from the front end of the hair transplanting part, and The amount of displacement (in mm) of the height of the front end of the handle body from the reference height after 10 seconds is defined as the bending amount B of the neck.

[2] The toothbrush according to [1], wherein the product of the amount of curvature A of the head and the amount of curvature B of the neck is 2-10.

[3] The toothbrush according to [1] or [2], wherein the product of the amount of curvature A'of the head and the amount of curvature B of the neck measured by the following method (α') It is 2.5~12.

Method (α'): The tufted surface of the head is directed upward in the vertical direction, and the position of the border between the head and the neck is moved 10 mm toward the shank, and the position is fixed. The height of the front end of the handle body below is the reference height, and in the fixed state, the length of the head in the long axis direction relative to the hair transplanting part is 10±10 from the front end of the hair transplanting part. Hang a 200g weight at 3% of the position, and shift the height of the front end of the handle body from the reference height after 10 seconds The amount (unit: mm) is set as the bending amount A'of the head.

[4] A toothbrush, characterized in that it comprises a handle body with a head, a neck extending on the head, and a handle extending on the neck, and planted on the hair grafting surface of the head Equipped with hair bundles, and the amount of curvature A'of the head measured by the following method (α') and the amount of curvature B of the neck measured by the following method (β) The product is 2.5-12.

Method (α'): The tufted surface of the head is directed upward in the vertical direction, and the position of the border between the head and the neck is moved 10 mm toward the shank, and the position is fixed. The height of the front end of the handle body below is the reference height, and in the fixed state, the length of the head in the long axis direction relative to the hair transplanting part is 10±10 from the front end of the hair transplanting part. A 200g weight was hung at 3%, and the height displacement (in mm) of the front end of the handle body after 10 seconds from the reference height was set as the bending amount A of the head '; Method (β): Make the tufted surface of the head face upward in the vertical direction, and use the height of the tip of the shank in a state where the position of the border between the neck and the shank is fixed as a reference Height, in the fixed state, relative to the length of the hair transplanting part in the head in the long axis direction, a 200g weight is hung on the position 50±3% from the front end of the hair transplanting part, and The amount of displacement (in mm) of the height of the front end of the handle body from the reference height after 10 seconds is defined as the bending amount B of the neck.

[5] The toothbrush according to any one of [1] to [4], wherein the thickness of the head is 2.0 mm to 4.0 mm.

[6] The toothbrush according to any one of [1] to [5], wherein the thickness of the head is 2.0 mm to 4.0 mm, and the smallest width and the smallest thickness of the neck are smaller The one side is 3.0mm~4.5mm.

[7] The toothbrush according to [6], wherein the smallest width of the neck is 3.0 mm to 4.5 mm.

[8] The toothbrush according to any one of [1] to [7], wherein the tip strength of the toothbrush bristles constituting the tuft is 1.7N to 3.0N.

[9] The toothbrush according to any one of [1] to [8], wherein the material of the handle body is polypropylene resin.

[10] The toothbrush according to any one of [1] to [9], wherein in the method (β), with respect to the length of the handle body in the long axis direction, the 42.4% of the positions from the front end are fixed.

[11] The toothbrush according to any one of [1] to [3] or [5] to [10], wherein the bending amount A and the bending amount B are A<B.

[12] The toothbrush according to any one of [1] to [3] or [5] to [11], wherein the difference (BA) between the bending amount A and the bending amount B is 1≦(BA )≦4.

[13] The toothbrush according to any one of [1] to [3] or [5] to [12], wherein the bending amount A is 0.5 to 3.0.

[14] The toothbrush according to any one of [1] to [13], wherein the bending amount B is 2.1 to 5.0.

[15] The toothbrush according to any one of [1] to [3] or [5] to [14], wherein the material of the handle body is polyacetal resin, and the bending amount A of the head is equal to Bend of the neck The product of the curvature B is 2 to 10, the thickness of the head is 2.0 mm to 4.0 mm, and the smaller of the smallest width and the smallest thickness of the neck is 3.0 mm to 4.5 mm.

[16] The toothbrush according to any one of [1] to [15], wherein the hair tufts are implanted on the tufted surface of the head in a form of flat-line type tufts.

The toothbrush of the present invention has more excellent cleaning power and more excellent feeling in use.

1: Toothbrush

2: head

4: neck

6: handle

9: The front end of the handle body

10: Handle body

20: Tufted surface

22: Planting pores

100: fixture

102: Weighing Hammer

200: ISO Hardness Tester

202: datum plane

204: Ladder

a: the absolute value of the difference between _{H 1} and H ₀

H ₀ : reference height

H ₁ : height

L1, L2, L3, L4: length

P1, P2: boundary

R1, R2: curve or straight line

S: 10±3% of the position from the front end of the tufted part relative to the long axis of the tufted hair

T2: The thickness of the neck (the smallest diameter of the neck)

W1: the width of the head

W2: the width of the neck

Fig. 1A is a plan view of a toothbrush according to an embodiment of the present invention.

Fig. 1B is a side view of the toothbrush according to the embodiment of the present invention.

Fig. 2A is a diagram illustrating a method of measuring the bending amount of the head.

Fig. 2B is a diagram illustrating a method of measuring the bending amount of the head.

Fig. 3 is a diagram illustrating a method of measuring the strength of the hair tip.

[First Invention]

Hereinafter, an embodiment of the toothbrush of the first invention will be described with reference to FIGS. 1A and 1B.

The toothbrush 1 of FIGS. 1A and 1B includes: a substantially quadrangular head 2 in a plan view, a neck 4 extending from the head 2, and a handle 6 extending from the neck 4 (hereinafter, also The head 2 together with the neck 4 and the handle 6 are called the handle body 10). A hair transplant part (not shown) is provided in the head 2.

The handle body 10 is one integrally molded into a long strip as a whole, for example, one obtained by injection molding using resin as a material.

As the material of the handle body, include: polypropylene resin (Polypropylene, PP), polyacetal resin (Polyoxymethylene (POM)), polystyrene resin (Polystyrene, PS), polyethylene terephthalate Resin (Polyethylene terephthalate, PET), Polybutylene terephthalate (PBT), Acrylonitrile Butadiene Styrene (ABS), polyarylate resin, polycarbonate Resin, Acrylonitrile Styrene (AS), Poly(1,4-cyclohexylene dimethylene terephthalic acid) (Poly(1,4-cyclohexylene dimethylene terephthalic acid), PCTA)) etc. Among these, in terms of high strength and excellent formability, PP, POM, and PBT are preferred, and PP and POM are more preferred. In addition, in terms of further obtaining the effects of the present invention at a lower cost, the material of the handle body is particularly preferably PP.

The resin can be used alone or in combination of two or more.

The bending elastic coefficient of the material of the handle body is preferably 1200 MPa to 3000 MPa, more preferably 1500 MPa to 3000 MPa. If the bending elastic modulus of the material of the handle body is in the above range, the bending amount of the head can be set to an appropriate value, and it is related to the improvement of cleaning power and operability in the oral cavity and the improvement of the user's feeling of use. Furthermore, the bending elastic modulus of the material of the handle body is measured in accordance with Japanese Industrial Standards (JIS) K7171.

In addition, part or all of the shank 6 of the shank body 10 may be covered with a soft resin. By covering part or all of the handle 6 with soft resin, it is possible to further improve the grip of the handle 6 by the user. Examples of the soft resin include: poly Elastomer resins such as olefin-based elastomers, styrene-based elastomers, polyester-based elastomers, and polyurethane-based thermoplastic elastomers, silicone resins, etc.

The length L1 of the handle body 10 can be determined in consideration of operability and the like, and is set to, for example, 150 mm to 200 mm.

The head 2 has a substantially quadrilateral flat plate shape with four tops formed by curved corners in a plan view with the longitudinal direction of the shank 10 as the long side. A plurality of hair transplanting holes 22 are formed on one surface (flocking surface 20) of the head 2. The tufts formed by bundling toothbrush bristles are implanted in this tufting hole 22, and the tufting part containing a plurality of tufts is formed.

In addition, in the present specification, the term "planar view" means that the toothbrush is viewed from the hair-implanted surface side of the head. The direction parallel to the flocking surface 20 and orthogonal to the longitudinal direction of the shank body 10 is defined as the width, and the direction orthogonal to the flocking surface 20 is defined as the thickness. In addition, the side facing the tufted surface 20 is referred to as the front surface, and the side opposite to the side facing the tufted surface 20 is referred to as the back surface.

In a plan view, the head 2 expands in the width direction from the front end 9 toward the neck 4, then extends with the same width, then shrinks in the width direction, and finally reaches the boundary P1 with the neck 4.

In the present embodiment, the boundary P1 is the end point of the curve forming the chamfered corner from the neck 4 in the top view shape of the head 2, that is, the position where the curve direction of the chamfered curve changes. In other words, the boundary P1 between the head and the neck is a curve or straight line R1 with both edges of the head that forms a corner cut from the neck and changes into a curve or straight line with an enlarged width, or The position of lines of the same width. In addition, in the case of a toothbrush whose width increases as the neck portion goes toward the handle in a plan view, the boundary P1 coincides with the position where the width of the head and the neck is the smallest in a plan view.

Furthermore, for example, like a toothbrush in which the head and neck are formed with the same width, it may be difficult to specify the position of the boundary P1. In this case, with respect to the length L1, the position 17.5% from the front end 9 of the shank body 10 (for example, when the length L1 is 180 mm, the position 31.5 mm from the front end 9 of the shank body 10) is set as the boundary P1 .

The size of the head 2 can be determined in consideration of operability in the oral cavity and the like.

If the maximum width W1 of the head 2 is too large, the operability in the oral cavity will be reduced, and if it is too small, the number of tufts for hair transplantation will be too small, and the cleaning power will be easily impaired. Therefore, the width W1 is set to, for example, 5 mm to 13 mm.

The thickness T1 of the head 2 is preferably 2.0 mm to 4.0 mm, more preferably 2.0 mm to 3.5 mm, and even more preferably 2.5 mm to 3.2 mm. If the thickness T1 is greater than or equal to the lower limit, it is easy to ensure sufficient strength in the head 2. Furthermore, it is easy to form the tufting holes 22 in the thickness direction, it is easy to firmly implant the tufts in the tufts 22, and it is easy to suppress the hair tufts from falling out. In addition, if the thickness T1 is equal to or less than the upper limit, the handleability of the toothbrush 1 in the oral cavity can be further improved. Furthermore, the toothbrush bristles can reach every corner of the oral cavity such as the depths of the molars, and the effect of removing dirt in the oral cavity can be further improved.

Furthermore, when the thickness of the head 2 is not fixed, T1 represents the minimum thickness of the head 2.

If the length L2 of the head 2 is too long, the operability in the oral cavity is likely to be impaired, and if it is too short, the number of tufts to be transplanted becomes too small, and the cleaning effect is likely to be impaired. Therefore, the length L2 is appropriately determined within the range of 10 mm to 40 mm, for example.

The shape of the pores 22 is not particularly limited, and can include: a perfect circle or an ellipse Polygons such as circles, triangles, or quadrilaterals.

The number of the transplanted pores 22 is not particularly limited, and is set to 10-60, for example.

The diameter of the tuft hole 22 is determined in accordance with the required thickness of the tuft, and is set to, for example, 1 mm to 3 mm.

The arrangement pattern of the tuft holes 22 is not particularly limited, and may be any arrangement pattern such as a so-called grid shape or a zigzag shape.

Examples of toothbrush bristles constituting the bristle bundle include: toothbrush bristles (tapered bristles) whose diameter gradually becomes smaller toward the tip of the bristles, brush bristles (straight bristles) with approximately the same outer diameter except for the rounded portion of the tip, and the tip of the bristles becomes grate-shaped , Spherical, split-end toothbrush bristles.

The toothbrush bristles are preferably tapered bristles. By setting the toothbrush bristles into tapered bristles, the effect of removing dirt from periodontal pockets can be improved. Furthermore, the massage effect of the gums can be improved, and the feeling of use can be further improved.

Examples of the material of the toothbrush bristles include polyamides such as 6-12 nylon and 6-10 nylon, PET, PBT, polytrimethylene terephthalate (PTT), and polyethylene naphthalate. Polyethylene naphthalate (PEN), polybutylene naphthalate (PBN) and other polyesters, polypropylene and other polyolefins, olefin-based elastomers, styrene-based elastomers, and other synthetic resin materials. One kind of these resin materials may be used alone, or two or more kinds may be used in combination.

In addition, the toothbrush bristles may have a multiple core structure having a core and at least one or more sheaths provided on the outside of the core.

The cross-sectional shape of the toothbrush bristles is preferably a perfect circle, but it is not necessarily limited to a perfect circle, and can be set to any shape corresponding to the intended use of the toothbrush 1. For example, it can be an ellipse, a polygon (for example, a triangle, a quadrilateral, a pentagon, a hexagon, etc.), a different shape (for example, a star shape, a three-leaf clover shape, a four-leaf clover shape, etc.).

The thickness of each toothbrush bristles is not particularly limited. For example, when the cross section is a perfect circle, it is preferably 4 mil to 8 mil (1 mil=1/1000 inch=0.025 mm). If it is more than the said lower limit value, the self-standing property will improve and cleaning property will become higher, and if it is less than the said upper limit value, the hairiness of the hair|bristle bundle 11 will become moderate, and the touch feeling will become more favorable.

The toothbrush bristles constituting the bristle bundle 11 may all have the same thickness, or two or more kinds of toothbrush bristles with different thicknesses may be combined.

The hair length of the toothbrush bristles, for example, the toothbrush bristles for adults is preferably set to 8 mm to 15 mm, and the toothbrush bristles for children are preferably set to 6 mm to 12 mm. In addition, in terms of usability and usability in the oral cavity, it is preferable that the smaller the diameter of the selected toothbrush bristles, the shorter the hair length of the toothbrush bristles. In addition, it is also possible to combine a plurality of toothbrush bristles with different thicknesses in accordance with the purpose of the usability, the brushing feeling, the cleaning effect, the durability, and the like.

The neck 4 connects the head 2 and the handle 6.

In the present embodiment, the neck 4 extends from the boundary P1 toward the shank 6 with approximately the same diameter, and then expands the diameter, and finally reaches the boundary P2 with the shank 6. The boundary P2 is the end point of the enlarged diameter of the neck 4, that is, the end point of the straight line forming the two edges of the widened part or the position where the bending direction of the curve forming the two edges of the widened part changes. If it is shown in Figure 1A, the boundary P2 between the neck and the handle is in the top view, The position where the straight line or the curved line R2 forming the two edges of the part with the increased width in the neck changes to the position where the width gradually decreases.

In addition, like a toothbrush in which the neck and the handle are formed with the same width, it may be difficult to specify the position of the boundary P2. In this case, with respect to the length L1, the position 42.2% from the front end 9 of the shank body 10 (for example, when the length L1 is 180 mm, the position 76.0 mm from the front end 9 of the shank body 10) is set as the boundary P2 .

The width W2 of the neck 4 is preferably 3.0 mm to 4.5 mm, more preferably 3.0 mm to 4.2 mm. If the width W2 is greater than or equal to the lower limit, it is easy to ensure sufficient strength in the neck 4 in terms of folding resistance and the like. Furthermore, the toothbrush 1 does not become too soft, and it is easy to obtain a good usability due to moderate bending. In addition, if the width W2 is equal to or less than the upper limit, the operability of the toothbrush 1 in the oral cavity can be improved. Furthermore, the toothbrush bristles can reach every corner of the oral cavity, and the dirt removal effect in the oral cavity can be further improved.

Furthermore, when the width of the neck 4 is not fixed, the width W2 represents the smallest width of the neck 4.

The thickness T2 of the neck 4 is preferably 3.0 mm to 4.5 mm, more preferably 3.0 mm to 4.2 mm. If the thickness T2 is greater than or equal to the lower limit, it is easy to ensure sufficient strength in the neck 4 in terms of folding resistance and the like. Furthermore, the toothbrush 1 does not become too soft, and it is easy to obtain a good usability due to moderate bending. In addition, if the thickness T2 is equal to or less than the upper limit, the handleability of the toothbrush 1 in the oral cavity can be improved. Furthermore, the toothbrush bristles can reach every corner of the oral cavity, and the dirt removal effect in the oral cavity can be further improved.

Furthermore, when the thickness of the neck 4 is not fixed, the thickness T2 represents the minimum thickness of the neck 4.

The minimum diameter of the neck 4 is preferably 3.0 mm to 4.5 mm, more preferably 3.0 mm to 4.2 mm. If the minimum diameter of the neck part 4 is more than the said lower limit, it will become easy to ensure sufficient strength in the neck part 4 in terms of folding resistance and the like. Furthermore, the toothbrush 1 does not become too soft, and it is easy to obtain a good usability due to moderate bending. Moreover, if the minimum diameter of the neck part 4 is below the said upper limit, the handleability of the toothbrush 1 in the oral cavity can be improved. Furthermore, the toothbrush bristles can reach every corner of the oral cavity, and the dirt removal effect in the oral cavity can be further improved.

In addition, the minimum diameter of the neck 4 indicates the smaller of the width W2 and the thickness T2, that is, the smaller of the smallest width and the smallest thickness of the neck 4. In the neck, it is more preferable that the smallest thickness is the same as the smallest width, or the smallest width is smaller than the smallest thickness, and the smallest width is 3.0mm~4.5mm.

The length L3 of the neck 4 can be determined in consideration of the length L2 of the head, etc., for example, a length of 30 mm to 90 mm, and more preferably 30 mm to 60 mm. If the length L3 is greater than or equal to the lower limit, the toothbrush bristles can easily reach every corner of the oral cavity, and the effect of removing dirt in the oral cavity can be further improved. If the length L3 is less than or equal to the upper limit, the operability of the toothbrush 1 in the oral cavity can be further improved.

(Bending amount A of head 2)

The bending amount A of the head is measured by the following method (α).

Method (α): Make the tufted surface of the head face upwards in the vertical direction to connect the head and neck of the toothbrush The height of the front end of the shank body in a state where the position of the boundary P1 of the part is fixed is the reference height. Furthermore, in a state where the position of the boundary P1 is fixed, a weight of 200 g is suspended at a position of 10±3% from the tip of the hair transplanting part with respect to the length of the hair transplanting part in the head in the long axis direction, and The amount of displacement (in mm) of the height of the tip of the handle body from the reference height after 10 seconds is defined as the bending amount A of the head.

In addition, the "length in the longitudinal direction of the tuft portion" refers to the distance between the front end of the tuft hole located on the most distal end side and the rear end of the tuft hole located on the rearmost end side when the head is viewed from above.

For example, when the width of the part from the head of the neck is the same when viewed from above, in the part of the neck from the head, the width is measured while slowly changing the position toward the head, and the width is the same The position of the turning point between the part of and the part where the width starts to increase is set as the boundary P1. In addition, when the width of the portion of the neck from the head in a plan view becomes smaller as it approaches the head, in the portion of the neck from the head, the width is measured while slowly changing the position toward the head. And the position where the width becomes the smallest is set as the boundary P1.

In the present invention, the bending amount A of the head 2 is measured as follows.

As shown in Fig. 2A, the toothbrush 1 is turned with the tufted surface 20 facing upwards and fixed with a clamp 100 at the position of the finest part of the neck (boundary P1). At this time, the height of the front end 9 of the handle body 10 is set as the reference height H ₀ .

Next, as shown in FIG. 2B, a weight 102 of 200 g is hung at the position of S, and the height of the front end 9 of the handle body 10 after 10 seconds is measured, and the height is set as H ₁ . The S is a position of 10±3% from the front end of the hair transplant part with respect to the long axis direction of the hair transplant. For example, when the tufting part is 19 mm, S is a position 2.0 mm from the tip.

Then, _{the absolute value of the difference between H 1} and H ₀ is determined as a (unit: mm). The a is measured by, for example, a height gauge or the like. The measurement is carried out at room temperature 25±3°C.

The measurement is performed 5 times, and the average value of the a is set as the bending amount A of the head 2.

The bending amount A is preferably 0.4 to 3.0, more preferably 0.4 to 2.5, and still more preferably 0.4 to 2.0. In addition, the bending amount A is preferably 0.5 to 3.0, more preferably 0.5 to 2.5, and even more preferably 0.5 to 2.0. If the bending amount A is in the above-mentioned range, the head 2 itself is appropriately bent, the flexibility of the hair graft part implanted in the head 2 appears, and the touch feeling to the gums, that is, the feeling of use becomes better. In addition, when the bending amount A is equal to or more than the lower limit, the feeling in use becomes good. If the bending amount A is equal to or less than the upper limit, it is easy to ensure sufficient strength in the head 2. Furthermore, the toothbrush 1 does not become too soft, and it is easy to obtain good oral operability and cleaning power.

Furthermore, the bending amount A is adjusted by adjusting the bending elastic coefficient of the material of the head 2 (that is, the material of the handle body 10), or the thickness, width, and the like of the head 2.

(Bending amount of neck 4)

The bending amount B of the neck is measured by the following method (β).

Method (β): Make the tufted surface of the head face upward in the vertical direction, and set the height of the tip of the handle body in a state where the position of the boundary between the neck of the toothbrush and the handle is fixed as the reference height. In the fixed state, relative to the length of the hair transplantation part in the long axis direction of the head Degree, hang a weight of 200g at 50±3% from the tip of the grafted part, and set the displacement (unit: mm) of the tip of the handle body after 10 seconds from the reference height Is the bending amount B of the neck.

In the present invention, it is the same as the bending amount A of the head 2 except that the position (boundary P1) of the toothbrush 1 is fixed by the jig 100 and the method of measuring the position S of the hanging weight 102 and the bending amount A of the head 2 is different. The bending amount B of the neck 4 is measured accordingly.

In the measurement of the bending amount B of the neck 4, the position where the toothbrush 1 is fixed by the jig 100 is the boundary P2. In addition, S is the position of 50±3% from the tip of the hair transplant part with respect to the length of the hair transplant part in the long axis direction. For example, when the tufting part is 19 mm, S is a position of 9.5 mm from the tip.

In addition, the absolute value of the difference between _{the reference height H 0} before hanging the weight 102 and the height H ₁ after 10 seconds has elapsed (unit: mm) is obtained in the same manner as the method for measuring the bending amount A of the head 2 ). The measurement is carried out at room temperature 25±3°C. This measurement is performed 5 times, and the average value thereof is defined as the bending amount B of the neck 4.

The bending amount B is preferably 2.1 to 5.0, more preferably 2.3 to 4.5, and still more preferably 2.5 to 4.0. When the bending amount B is in the above-mentioned range, the neck 4 is appropriately bent, a moderate cushioning property appears, and the touch feeling of the hair transplantation part with respect to the gums becomes better. In addition, if the bending amount B is more than the above-mentioned lower limit value, the toothbrush bristles can reach every corner of the oral cavity such as the depth of the molar teeth, and the cleaning force in the oral cavity can be further improved. Furthermore, the penetration of the toothbrush bristles into the periodontal pocket is improved, and the cleaning power of the periodontal pocket can be further improved. If the bending amount B is equal to or less than the upper limit, it is easy to ensure sufficient strength in the neck 4. Furthermore, the toothbrush 1 does not become too soft, and it is easy to obtain a good feeling in use.

Furthermore, the bending amount B is adjusted by adjusting the bending elastic coefficient of the material of the neck 4 (that is, the material of the handle body 10), the minimum diameter of the neck, the cross-sectional shape of the boundary P2, and the like.

The product (A×B) of the bending amount A of the head and the bending amount B of the neck is 0.8 to 10, more preferably 1 to 10, further preferably 1 to 6, and still more preferably 1 to 3.5. In addition, (A×B) is preferably 2-10. If (A×B) is in the above-mentioned range, a moderate bending of the head 2 and the neck 4 can be obtained. Thereby, when the hair transplantation part is slid with respect to the cleaning target site (teeth, gums, etc.), the flexibility and cushioning properties of the hair transplantation part appear, and the contact feeling of the hair transplantation part becomes good. In addition, the lower limit of (A×B) is 0.8 or more, preferably 1 or more. In addition, it is preferably 2 or more. When (A×B) is equal to or higher than the lower limit value, a moderate bending can be obtained, whereby a good touch feeling to the gums is obtained, and a high massage effect is obtained to the gums, and the feeling of use is improved. The upper limit of (A×B) is 10 or less, preferably 6 or less, and more preferably 3.5 or less. When (A×B) is equal to or less than the upper limit, it is possible to prevent the area formed by the head 2 and the neck 4 from being excessively bent, resulting in a decrease in operability and a decrease in cleaning power. In addition, it is possible to suppress the decrease in the massage effect on the gums caused by the excessive bending, or the user's feeling of softness when using the toothbrush 1. Furthermore, the strength of the toothbrush 1 can be improved, and durability can be improved.

The bending amount A and the bending amount B are preferably A<B. If A<B, the operability of the toothbrush 1 can be further improved.

In addition, the difference (B-A) between the bending amount A and the bending amount B is preferably 1 or more, more preferably 1.5 or more, and still more preferably 2 or more. If (B-A) is above the lower limit, the bending amount of the neck 4 is kept large relative to the head 2, and the cushioning can be improved. It is easy to feel the massage effect on the gums, and the user feels the massage effect on the gums.

In addition, (B-A) is preferably 4 or less, more preferably 3 or less. If (B-A) is equal to or less than the upper limit, the amount of curvature of the neck 4 with respect to the head 2 does not become too large, and it is easy to improve the operability in the oral cavity. Furthermore, it is easy to prevent the user from feeling soft when using the toothbrush 1.

(B-A) is preferably 1~4, more preferably 1~3.

In addition, the ratio (B/A) of the bending amount B to the bending amount A is preferably 1.5 to 5.0, and more preferably 1.8 to 4.8.

(Bending amount A'of head 2)

The bending amount A'of the head is measured by the following method (α').

Method (α'): Make the hair transplanted surface of the head face upward in the vertical direction, and move the position of the toothbrush from the position of the border between the head and the neck of the toothbrush to the handle side by 10mm and fix the handle body The height of the front end is the reference height. In the fixed state, with respect to the length of the hair transplanting part in the long axis direction of the head, a 200g weight is hung at a position 10±3% from the tip of the hair transplanting part, and the handle after 10 seconds The amount of displacement (in mm) of the height of the front end of the body from the reference height is defined as the bending amount A'of the head.

In the present invention, except that the position (boundary P1) of the toothbrush 1 is fixed by the jig 100 and the method of measuring the bending amount A of the head 2 is different, the bending amount A of the head 2 is measured in the same manner as the bending amount A of the head 2 '.

In the measurement of the bending amount A′ of the head 2, the position where the toothbrush 1 is fixed by the jig 100 is a position P3 moved 10 mm from the position of the boundary P1 to the handle side in the long axis direction.

In addition, the absolute value of the difference between _{the reference height H 0} before hanging the weight 102 and the height H ₁ after 10 seconds has elapsed (unit: mm) is measured in the same manner as the method for measuring the bending amount A of the head 2 . The measurement is carried out at room temperature 25±3°C. This measurement is performed 5 times, and the average value thereof is defined as the bending amount A′ of the head 2.

The bending amount A'is preferably 1 to 5, more preferably 1 to 4, and still more preferably 1 to 3. If the bending amount A'is in the above range, the head 2 itself is appropriately bent, the flexibility of the hair transplantation part implanted in the head 2 appears, and the touch feeling to the gums, that is, the feeling of use becomes better. In addition, when the bending amount A'is equal to or more than the lower limit, the feeling in use becomes good. If the bending amount A'is equal to or less than the upper limit, it is easy to ensure sufficient strength in the head 2. Furthermore, the toothbrush 1 does not become too soft, and it is easy to obtain good oral operability and cleaning power.

Furthermore, the bending amount A'is adjusted by adjusting the bending elastic coefficient of the material of the head 2 (that is, the material of the handle body 10) or the thickness, width, etc. of the head 2.

The product of the bending amount A'of the head and the bending amount B of the neck (A'×B) is preferably 2.5-12, more preferably 3-12, further preferably 3-10, and still more preferably 3-7 . If (A'×B) is in the above-mentioned range, it is easy to obtain a moderate bending of the head 2 and the neck 4 in harmony. Thereby, when the hair transplantation part is slid relative to the cleaning target site (teeth, gums, etc.), the flexibility and cushioning properties of the hair transplantation part appear, and the contact feeling of the hair transplantation part becomes better. In addition, (A'×B) is 2.5 or more, preferably 3 or more. By (A'×B) Above the lower limit value, moderate bending can be obtained, whereby the contact sensation on the gums is better, and a higher massage effect on the gums can be obtained, and the feeling of use is further improved. (A'×B) is 12 or less, preferably 10 or less, more preferably 7 or less. When (A'×B) is equal to or less than the upper limit value, it is easy to suppress the excessive bending of the area formed by the head 2 and the neck 4, which may cause a decrease in operability and a decrease in cleaning power. In addition, it is possible to suppress the decrease in the massage effect on the gums caused by the excessive bending, or the user's feeling of softness when using the toothbrush 1. Furthermore, the strength of the toothbrush 1 can be improved and the durability can be further improved.

In addition, the ratio of the bending amount B to the bending amount A'(B/A') is preferably 0.8 to 2.5, more preferably 0.9 to 2.0.

(The tip strength of the toothbrush bristles)

The tip strength of the toothbrush bristles constituting the bristle bundle is measured as follows.

As a measuring device, an ISO roughness tester was used. The ISO roughness tester 200 shown in FIG. 3 includes a reference surface 202 and a ladder 204 arranged on the reference surface. The ladder 204 includes a plurality of cylindrical rod-shaped bodies (made of stainless steel, diameter: 3 mm). The rod-shaped bodies are arranged in parallel with each other at a fixed interval (the centers of the rod-shaped bodies are 10 mm apart from each other).

First, the toothbrush 1 is set on the testing machine 200. At this time, the tip of the toothbrush bristles implanted in the head 2 of the toothbrush 1 is brought into contact with the reference surface 202 of the testing machine 200. Then, the maximum resistance value when the head 2 is horizontally slid with respect to the reference surface 202 is obtained, and this is used as the tip strength of the toothbrush bristles. The sliding direction of the head 2 is the direction where the longitudinal direction of the toothbrush 1 and the longitudinal direction of the rod-shaped body become perpendicular to each other. to. The sliding speed of the head 2 is set to 10 mm/min.

The tip strength of the toothbrush bristles is preferably 1.7N~3.0N, more preferably 1.9N~2.8N. If the tip strength of the toothbrush bristles is in the above-mentioned preferred range, the removal power of dental plaque can be further improved, and the contact feeling of the toothbrush bristles with the gums becomes better, and the usability can be further improved.

The toothbrush 1 of this embodiment is manufactured according to the manufacturing method of a conventionally well-known toothbrush. For example, a hard resin is injected into a mold to shape the handle body 10. Then, tufts of hair are planted on the flocking surface 20 of the obtained handle body 10, whereby the toothbrush 1 can be obtained. As a method of planting hair bundles, for example, it is possible to cite: folding the hair bundles in half and punching the flat threads sandwiched between them into the pores 22, thereby planting the hair bundles in the flat line type hair transplantation; in the molten resin that becomes the hair transplantation part The thermal welding method that presses in and fixes the lower end of the tuft; after heating the lower end of the tuft to form a molten mass, the molten resin is poured into a mold to shape the tufted part, etc.

The toothbrush of the first invention is particularly effective when it is used as a toothbrush in which tufts of hair are transplanted by flat-line-type hair transplantation. When the flat thread is used for flocking, the load generated by the flat thread is applied to the head. Therefore, the thinner the head becomes, the lower the strength against deformation when a force is applied becomes. In the toothbrush 1 of this embodiment, the force applied to the head can be distributed from the head to the entire neck when brushing teeth, etc., by providing the neck with moderate flexibility. Therefore, in the case of flat-line hair transplantation, the effect of the present invention can be obtained particularly remarkably.

Especially in the case of a toothbrush with a flat-line hair transplantation using a low-strength polypropylene resin as the material of the handle body, the bending of the head relative to the length (L2) of the head When the value X of the amount of curvature (A/L2) is set to 0.015 to 0.045, it is preferable to set the amount of curvature of the neck (B/(L2+L3) relative to the sum of the length of the head and the neck (L2+L3) The ratio of the value Y of )) to the X, that is, Y/X is set to 0.8 to 2.0. The X is preferably set to 0.018 to 0.45, more preferably to 0.018 to 0.040, at this time, it is preferable to set Y/X to 0.9 to 2.0, more preferably to 0.9 to 1.9.

In addition, in the case of using a high-strength polyacetal resin as a toothbrush with flat-line hair transplantation as the handle body material, when the X is set to 0.027 to 0.035, preferably 0.029 to 0.032, it is preferable In order to set the Y/X to 1.0 to 1.4, it is more preferable to set it to 1.0 to 1.3.

The usage method of the toothbrush 1 of this embodiment is demonstrated.

First, hold the handle 6. The shape of the grip 6 is not particularly limited, and it may be a palm grip type or a pen grip type. Normally, cleaning is performed while applying pressure to the target part. Therefore, in any gripping mode, the thumb or the like is placed near the boundary P2 of the rear end of the neck to grip the handle 6.

Then, the head 2 is inserted into the oral cavity, while pressing the handle 6, while sliding the hair transplantation part on the cleaning target site. The force applied to the handle 6 is transmitted to the head 2 through the neck 4, and then transmitted from the head 2 to the hair transplanting part, whereby the hair transplanting part performs cleaning while applying pressure to the cleaning target part. At this time, since the product (A×B) of the bending amount A of the head and the bending amount B of the neck is 0.8 to 10, a moderate bending of the head and the neck can be obtained. As a result, the toothbrush bristles implanted in the head 2 of the toothbrush 1 can easily reach every corner in the oral cavity such as the depth of the molars, and the cleaning force in the oral cavity can be improved. Furthermore, it is easy for the toothbrush bristles to enter the periodontal pockets, which can improve the cleaning of the periodontal pockets force. In addition, by obtaining a moderate curvature, the flexibility and cushioning properties of the hair transplantation part are improved, the contact feeling of the hair transplantation part to the gums becomes better, a good massage effect on the gums can be obtained, and the feeling of use can be improved.

In addition, if the product (A'×B) of the bending amount A'of the head and the bending amount B of the neck is 2.5 to 12, it is easier to obtain a moderate bending of the head and the neck in harmony. Thereby, the cleaning power of the deep part of the molars in the oral cavity, periodontal pockets, etc. can be further improved, and a good massage effect on the gums can be easily obtained, and the feeling of use can be further improved.

In addition, if the thickness T1 of the head 2 is 2.0mm~4.0mm, and the minimum diameter of the neck 4 is 3.0mm~4.5mm, it is easier for the toothbrush bristles implanted in the head 2 to reach the depths of the molars, etc. Every corner of the oral cavity can further improve the cleaning power in the oral cavity. Furthermore, the operability of the toothbrush 1 can be further improved.

Furthermore, if the hair tip strength is 1.7N to 3.0N, it is easier for the toothbrush bristles to enter the periodontal pocket, and the cleaning power of the periodontal pocket can be further improved. Furthermore, the feeling of contact with the gums becomes better, and the feeling of use can be further improved.

[Second Invention]

The toothbrush of the second invention is characterized in that it includes a head implanted with tufts of hair, a neck extending on the head, and a handle extending on the neck, and the amount of curvature A'of the head and the amount of curvature of the neck The product of the bending amount B (A'×B) is 2.5-12. The toothbrush of the second invention can take the same form as the toothbrush of the first invention, except that the product (A'×B) of the amount of curvature A'of the head and the amount of curvature B of the neck is 2.5-12. The shape is also the same.

Regarding A'×B, it is as described in the first invention.

In the toothbrush of the second invention, due to the bending amount A'of the head and the bending of the neck The product of the quantity B (A'×B) is 2.5 to 12, so a moderate bending of the head and neck can be obtained. As a result, the toothbrush bristles implanted in the head of the toothbrush can easily reach every corner in the oral cavity such as the depth of the molars, and the cleaning power in the oral cavity can be improved. Furthermore, it is easy for the toothbrush bristles to enter the periodontal pocket, and the cleaning power of the periodontal pocket can be improved. In addition, by obtaining a moderate curvature, the flexibility and cushioning properties of the hair transplantation part are improved, the contact feeling of the hair transplantation part to the gums becomes better, a good massage effect on the gums can be obtained, and the feeling of use can be improved.

The following examples illustrate the present invention in more detail, but the present invention is not limited to these examples.

The materials used in this example are as follows.

<Handle body>

‧POM-1 (flexural elastic modulus: 2600MPa)

‧PP-1 (flexural elastic modulus: 1900MPa)

‧PP-2 (flexural elastic modulus: 1400MPa)

<Toothbrush bristles>

‧PBT

(Example 1~Example 3, Comparative Example 1~Comparative Example 2)

The same toothbrush as in Fig. 1A and Fig. 1B was produced. The length L1 of the handle body of the toothbrush of each example is 180mm, and the thickness of the head T1, the length L2 of the head, the width of the head W1, the minimum diameter of the neck T2, the length L3 of the neck, the width of the boundary P2, The thickness of the boundary P2 was set to the size shown in Table 1. In the head, 23 toothbrush bristles (manufactured by PBT) are bundled as a tuft, and the tuft is planted in the tuft pattern shown in Fig. 1A, And set up the tufting department. In addition, the length and thickness of the toothbrush bristles of each example were made into the size shown in Table 1.

The material of the toothbrush of each example is as shown in Table 1.

In addition, the amount of curvature A of the head and the amount of curvature B of the neck of the toothbrush of each example were measured by the method described above, and the tip strength (position of the boundary P1: 31.5 mm from the front end 9 of the handle body 10, position of the boundary P2: (76.0 mm from the front end 9 of the handle body 10).

Table 1 shows the bending amount A, bending amount B, A×B, and hair tip strength of the toothbrush of each example.

(Example 4~Example 9, Comparative Example 3~Comparative Example 7)

The same toothbrush as in Fig. 1A and Fig. 1B was produced. The length L1 of the handle body of the toothbrush of each example is 180mm (Example 4~Example 9, Comparative Example 3~Comparative Example 7), the thickness T1 of the head, the length L2 of the head, the width W1 of the head, and the neck The minimum diameter T2 of the portion, the length L3 of the neck portion, the width of the boundary P2, and the thickness of the boundary P2 were set to the dimensions shown in Table 2 and Table 3. In the head, 23 toothbrush bristles (manufactured by PBT) were bundled as a tuft, and the tuft was planted in the tufting pattern shown in FIG. 1A to provide a tufting part. In addition, the length and thickness of the toothbrush bristles of each example were made into the size shown in Table 2 and Table 3.

The material of the toothbrush of each example is as shown in Table 2 and Table 3.

In addition, the amount of curvature A of the head of the toothbrush of each example, the amount of curvature A'of the head, the amount of curvature B of the neck, and the tip strength were measured by the method described above. In the toothbrush of each example, the position of the boundary P1 of the fixed toothbrush and the position of the boundary P2 are determined as described above.

The amount of bending A, the amount of bending A', the amount of bending B, A×B, A'×B, And the hair tip strength is shown in Table 2 and Table 3.

In addition, regarding the toothbrush of each example, the cleaning power, the feeling of use, and the operability were evaluated as follows.

The respective evaluation results are shown in Tables 1 to 3.

[Cleaning power in the depths of the molars (the throat side of the molars)]

Ten monitoring personnel cleaned the oral cavity with the toothbrush of each example, and evaluated the cleaning effect of the deep part of the molar tooth at this time based on the following evaluation criteria. The average score of 10 monitoring personnel is 4 or more as "○", the average score is 2 or more and less than 4 points is "△", and the average score is less than 2 points as "×".

<Evaluation criteria>

5 points: The tactile sensation of the dirt falling from the depths of the molars is very felt.

4 points: The tactile sensation of the dirt falling from the depths of the molar teeth is strongly felt.

3 points: Feel the tactile sensation of dirt falling from the depths of the molars.

2 points: The tactile sensation of the dirt falling from the depths of the molar teeth is not much felt.

1 point: The tactile sensation of dirt falling from the depths of the molar teeth is not felt.

[Evaluation of usability]

Ten monitoring personnel cleaned the oral cavity using the toothbrush of each example, evaluated the contact sensation to the gums at this time based on the following evaluation criteria, and evaluated the use sensation of the toothbrush. The average score of 10 monitoring personnel is 4 or more as "○", the average score is 2 or more and less than 4 points is "△", and the average score is less than 2 points as "×".

<Evaluation criteria>

5 points: There is no gum pain, and the touch feeling is very excellent.

4 points: There is no gum pain, and the touch feeling is excellent.

3 points: There is no gum pain, and the touch feeling is excellent.

2 points: A slight pain is felt in the gums.

1 point: A strong pain is felt in the gums.

[Operability in the oral cavity]

Ten monitoring personnel cleaned the oral cavity and evaluated the operability of the toothbrush in each case. The evaluation of operability is set to 7 stages from 1 to 7 points, and the more people feel that the operability is good, the higher the score becomes. The average scores of 10 monitoring personnel were classified into the following judgment criteria, and the operability in the oral cavity was judged.

<Judgment Criteria>

○: The average score is 5 points or more.

△: The average score is 3 or more and less than 5 points.

×: The average score is less than 3 points.

As shown in Table 1, the toothbrushes to which Example 1, Example 2, and Example 3 of the present invention are applied have excellent cleaning power in the oral cavity and a good feeling of use. Furthermore, the operability in the oral cavity is excellent.

In contrast, toothbrushes with A×B less than 0.8 (Comparative Example 1) and toothbrushes with A×B greater than 10 (Comparative Example 2) had insufficient cleaning power against the depths of the molars, and they could not be obtained in the oral cavity. Good operability.

In addition, as shown in Table 2, the toothbrush of the present invention (Example 4 to Example 9) has excellent cleaning power in the oral cavity and a good feeling in use. Furthermore, in the oral cavity The operability is excellent.

On the other hand, as shown in Table 3, toothbrushes with A×B less than 0.8 and A'×B less than 3 (Comparative Examples 3 to 7) have a cleaning force against the depths of molars and periodontal pockets. At least one of the cleaning power, the feeling of use, and the operability in the oral cavity is not sufficient.

From the above results, it can be confirmed that the toothbrush of the present invention has more excellent cleaning power in the oral cavity and more excellent usability.

1‧‧‧Toothbrush

2‧‧‧Head

4‧‧‧Neck

6‧‧‧Handle

9‧‧‧The front end of the handle body

10‧‧‧Handle body

20‧‧‧Flocking surface

22‧‧‧Pore-planting

L1, L2, L3, L4‧‧‧Length

P1, P2‧‧‧Boundary

R1, R2‧‧‧Curve or straight line

W1‧‧‧The width of the head

W2‧‧‧Width of neck

Claims (9)

A toothbrush, characterized in that it comprises a handle body with a head, a neck extending on the head, and a handle extending on the neck, and is planted on the tufted surface of the head There are hair bundles, and the product of the amount of curvature A of the head measured by the following method (α) and the amount of curvature B of the neck measured by the following method (β) is 0.8 ~10. Method (α): Make the hair transplanted surface of the head face upward in the vertical direction to fix the position of the border between the head and the neck at the front end of the handle body The height is the reference height, and in the fixed state, with respect to the length of the hair transplantation part in the head in the long axis direction, 200g is hung at a position 10±3% from the tip of the hair transplantation part Weight, and set the displacement amount of the height from the reference height of the front end of the handle body after 10 seconds as the bending amount A of the head, wherein the displacement amount is in mm; method ( β): The tufted surface of the head is directed upward in the vertical direction, and the height of the tip of the shank in a state where the position of the border between the neck and the shank is fixed is the reference height, In the fixed state, with respect to the length of the hair transplanting part in the head in the long axis direction, a 200g weight is hung at a position 50±3% from the tip of the hair transplanting part, and The amount of displacement of the height from the reference height of the front end of the handle body after 10 seconds is set as the bending amount B of the neck, wherein the unit of the displacement amount is mm. The toothbrush according to item 1 of the scope of patent application, wherein the product of the bending amount A of the head and the bending amount B of the neck is 2-10. The toothbrush according to item 1 or item 2 of the scope of patent application, wherein the product of the bending amount A'of the head and the bending amount B of the neck is measured by the following method (α') 2.5~12, method (α'): make the hair transplanted surface of the head face upward in the vertical direction, so as to move 10mm from the position of the border between the head and the neck to the shank side The height of the front end of the handle body in the fixed position is the reference height, and in the fixed state, the length relative to the long axis direction of the hair transplantation part in the head is obtained from the hair transplant A 200g weight is hung at 10±3% from the tip of the part, and the displacement amount of the tip of the handle body from the reference height after 10 seconds is set as the amount of bending of the head A', wherein the unit of the displacement is mm. A toothbrush, characterized in that it comprises a handle body with a head, a neck extending on the head, and a handle extending on the neck, and is planted on the tufted surface of the head There are hair bundles, and the product of the amount of curvature A'of the head measured by the following method (α') and the amount of curvature B of the neck measured by the following method (β) 2.5~12, method (α'): make the hair transplanted surface of the head face upward in the vertical direction, so as to move 10mm from the position of the border between the head and the neck to the shank side The height of the front end of the handle body in the fixed position is the reference height, and in the fixed state, the length relative to the long axis direction of the hair transplantation part in the head is obtained from the hair transplant A 200g weight is hung at 10±3% from the tip of the part, and the displacement amount of the tip of the handle body from the reference height after 10 seconds is set as the amount of bending of the head A', wherein the unit of the displacement is mm; Method (β): Make the tufted surface of the head face upward in the vertical direction, and use the height of the tip of the shank in a state where the position of the border between the neck and the shank is fixed as a reference Height, in the fixed state, and further with respect to the length of the hair transplanting part in the head in the long axis direction, a weight of 200g is suspended at a position 50±3% from the tip of the hair transplanting part, The displacement amount of the height from the reference height of the front end of the handle body after 10 seconds is set as the bending amount B of the neck, wherein the unit of the displacement amount is mm. The toothbrush according to item 1 or item 4 of the scope of patent application, wherein the thickness of the head is 2.0mm~4.0mm. The toothbrush according to item 1 or item 4 of the scope of the patent application, wherein the thickness of the head is 2.0mm~4.0mm, and the smallest of the smallest width and the smallest thickness of the neck is 3.0 mm~4.5mm. The toothbrush according to item 6 of the scope of patent application, wherein the smallest width of the neck is 3.0mm~4.5mm. The toothbrush according to item 1 or item 4 of the scope of patent application, wherein the tip strength of the toothbrush bristles constituting the tuft is 1.7N-3.0N. The toothbrush according to item 1 or item 4 of the scope of patent application, wherein the material of the handle body is polypropylene resin.

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