CN109152470B

CN109152470B - Tooth brush

Info

Publication number: CN109152470B
Application number: CN201780030993.9A
Authority: CN
Inventors: 木本雄也; 阿部徹弥; 高桥纯
Original assignee: Lion Corp
Current assignee: Lion Corp
Priority date: 2016-05-23
Filing date: 2017-05-23
Publication date: 2021-05-28
Anticipated expiration: 2037-05-23
Also published as: JP7162409B2; KR20230027310A; JP2017209147A; KR20190007406A; CN109152470A; KR102693131B1; WO2017204204A1

Abstract

The invention aims to provide a toothbrush which has a soft massage feeling on a wide range of gingiva and ensures high cleaning performance of a tooth neck. The toothbrush is provided with a handle body (2) provided with a brush head part (4) at the front end, and a plurality of bristle bundles implanted with bristles are formed in a plurality of implantation holes on a bristle implanting surface (5) of the brush head part. The hair-planting surface is provided with: an inner hair-planting region (11) in which a plurality of inner hair bundles are arranged in parallel in the direction of the axis (O) of the handle body and planted in the approximate center in the width direction perpendicularly intersecting the axis; and an outer hair-planting region (21) in which a plurality of outer hair bundles are implanted with the inner hair bundles sandwiched therebetween in the width direction, and the maximum length L of all the hair-planting regions in which the plurality of inner hair bundles and the plurality of outer hair bundles are implanted in the width direction is 12.0mm to 16.0 mm; the maximum length of the outer side hair planting area in the width direction is 6.5 mm-9.5 mm; the maximum length of the inner side hair planting area in the width direction is 4.0 mm-5.5 mm; the diameter of the outer side hair bundle is 1.4 mm-1.8 mm; the diameter of the inner side hair bundle is 1.0 mm-1.4 mm.

Description

Tooth brush

Technical Field

The present invention relates to toothbrushes.

The present application claims priority from Japanese patent application No. 2016-.

Background

For consumers who pay attention to the prevention of periodontal disease, a toothbrush having a gentle touch feeling that does not damage the gum as much as possible and a high cleaning force for the tooth neck is desirable. In recent years, consumers have also paid attention to "a soft massaging feeling of the gums". However, in the conventional periodontal disease prevention toothbrush, a compact head is important, and the amount of bristles contacting the gums in a normal brushing is small, so that a sufficient massage effect cannot be obtained. Therefore, a toothbrush is being sought which tufts touch a wide range of gums and has a high cleaning power of the cervical part.

Conventionally, as a technique for achieving both a soft touch feeling and a tooth neck cleaning force, the following toothbrushes have been proposed: a toothbrush having an outer portion with a large aperture and a high bristle density and a very high ratio of the bristle density between the outer portion and the inner portion (see patent document 1), and a toothbrush having an outer peripheral bristle-implanted region formed of very fine tufts (see patent document 2).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2012-034845

Patent document 2: japanese patent laid-open publication No. 2011-

Disclosure of Invention

Problems to be solved by the invention

However, the above-described conventional techniques have the following problems.

In order to make the tufts touch a wide range of gums, it is necessary to make the brush head wide, but in the toothbrush described in patent document 1, the outer side of the implanted portion is made of thick tufts, and therefore if it is made wide, the interference of the tufts is large, and the bristles are not bent. Therefore, only the front end of the hair comes into contact with the gum, and efficient massage is difficult. When the hair bundle is implanted into the implantation hole having a large diameter, the tip of the hair bundle is formed into a pencil shape (mountain shape), so that the amount of hair contacting the gum is reduced, resulting in a low efficiency of the massage.

On the other hand, the toothbrush described in patent document 2 has a problem that the outer peripheral implanted hair region is formed of very small tufts and therefore is easily bent, and the deflection of the tufts in the central implanted hair region contributing to the periodontal pocket cleaning ability cannot be suppressed, and the rigidity of the distal end of the hair cannot be secured. Further, the toothbrush described in patent document 2 has a problem that the ratio of the central implanted hair region to the outer peripheral implanted hair region is small, and the cleaning power of the tooth neck portion is insufficient when brushing the teeth and the gum at the same time.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a toothbrush which has a gentle massaging feeling over a wide range of gums and ensures high cleaning performance for the neck of the teeth.

Means for solving the problems

According to a first aspect of the present invention, there is provided a toothbrush comprising a handle body having a brush head portion at a distal end thereof, and a bristle bundle in which bristles are implanted in a plurality of implantation holes formed in an implantation surface of the brush head portion, wherein the implantation surface has an inner implantation region and an outer implantation region: in the inner hair-attachment region, a plurality of inner hair bundles are arranged in parallel in an axial direction of the handle body and are attached to substantially a center in a width direction perpendicular to the axial direction, a plurality of outer hair bundles are attached to the outer hair-attachment region with the inner hair bundles interposed therebetween in the width direction, a maximum length of all of the hair-attachment regions to which the plurality of inner hair bundles and the plurality of outer hair bundles are attached in the width direction is 12.0mm or more and 16.0mm or less, a maximum length of the outer hair-attachment region in the width direction is 6.5mm or more and 9.5mm or less, a maximum length of the inner hair-attachment region in the width direction is 4.0mm or more and 5.5mm or less, a hair bundle diameter of the outer hair bundles is 1.4mm or more and 1.8mm or less, and a hair bundle diameter of the inner hair bundles is 1.0mm or more and 1.4mm or less.

Further, according to the toothbrush of one embodiment of the present invention, when a value obtained by dividing the total number of bristles constituting the plurality of outer tufts by the area of the outer tuft region is defined as an outer tuft density and a value obtained by dividing the total number of bristles constituting the plurality of inner tufts by the area of the inner tuft region is defined as an inner tuft density, a tuft density ratio represented by outer tuft density/inner tuft density is 1.4 or more and 2.5 or less.

In addition, according to the toothbrush according to the above-described one embodiment of the present invention, the length of the inner tufts on the bristle surface is longer than the length of the outer tufts on the bristle surface.

In addition, according to the toothbrush according to the one embodiment of the present invention, at least one of the inner tufts and the outer tufts includes bristles having a diameter gradually decreasing toward the tips of the bristles.

Further, according to the toothbrush according to the one embodiment of the present invention, the inner tufts and the outer tufts are arranged in a staggered pattern in which positions of adjacent tufts in the axial direction are shifted in the width direction; the maximum length of all the hair-planted regions in the width direction is 12.0mm to 15.0 mm; the maximum length of the outer side hair-planting region in the width direction is more than 7.0mm and less than 9.5 mm; when a value obtained by dividing the total number of bristles constituting the plurality of outer side tufts by the area of the outer side bristle-implanted region is defined as an outer side bristle-implanted density, and a value obtained by dividing the total number of bristles constituting the plurality of inner side tufts by the area of the inner side bristle-implanted region is defined as an inner side bristle-implanted density, a bristle-implanted density ratio represented by the outer side bristle-implanted density/the inner side bristle-implanted density is 1.4 or more and 2.0 or less.

Effects of the invention

According to the present invention, a toothbrush capable of providing a gentle massaging feeling to a wide range of gums and ensuring high cleaning performance of the tooth neck portion can be provided.

Drawings

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

Fig. 2 is a left side view of the brush head portion of the toothbrush 1 shown in fig. 1.

FIG. 3 is a plan view showing a head portion of a toothbrush according to an embodiment of the present invention.

FIG. 4 is a view showing specifications and evaluations of examples and comparative examples.

[ description of symbols ]

1. 1A … toothbrush, 2 … handle body, 4 … brush head, 5 … bristle-implanting surface, 11 … inner bristle-implanting region, 12 … inner bristle bundle, 21 … outer bristle-implanting region, 22 … outer bristle bundle, O … axis

Detailed Description

Hereinafter, an embodiment of the toothbrush of the present invention will be described with reference to fig. 1 to 4.

The following embodiments are illustrative of one embodiment of the present invention, and are not intended to limit the present invention, and may be modified arbitrarily within the scope of the technical idea of the present invention. In the following drawings, the actual structure is different from the structures in scale, number, and the like in order to facilitate understanding of the structures.

The toothbrush of the present invention will be described with reference to the following drawings. Fig. 1 is a plan view showing a brush head portion of a toothbrush 1 according to an embodiment of the present invention, and fig. 2 is a left side view of the brush head portion of the toothbrush 1 shown in fig. 1.

As shown in fig. 1, the toothbrush 1 includes a handle body 2, and the handle body 2 is substantially composed of an elongated grip portion (not shown) and a head portion 4 provided at a distal end of the grip portion. In fig. 1, reference symbol O denotes an axis of the handle body 2, i.e., a line passing through the center of the handle body 2 in the longitudinal direction of the handle body 2.

The brush head portion 4 is formed into an approximately rectangular shape having a length in the direction of the axis O in a plan view, and any surface thereof is formed as a bristle implanting surface 5 into which a bristle bundle is implanted. On the hair-planted surface 5, a plurality of inner planting holes 10 (27 holes in fig. 1 as an example) having a bottomed cylindrical shape are formed on and along the axis O in fig. 1. The plurality of inner implanted holes 10 are arranged in a staggered manner such that the positions of the inner implanted holes 10 adjacent to each other in the direction of the axis O are shifted in the width direction of the brush head 4 (the direction perpendicular to the direction of the axis O). Inner tufts 12 formed by bundling a plurality of inner bristles 13 into a substantially cylindrical shape are implanted into the inner implanted holes 10, respectively, to form an inner tuft group 14. Therefore, the inner tufts 12 are arranged in a staggered pattern in which the positions of the inner tufts 12 adjacent to each other in the axial direction are shifted in the width direction of the head portion 4.

Further, on the implanted surface 5, a plurality of outer implanted holes 20 (30 as an example in fig. 1) having a bottomed cylindrical shape are formed along the axis O with the inner implanted holes 10 interposed therebetween in the width direction, and outer tufts 22 bundling a plurality of outer brush staples 23 into a substantially columnar shape are implanted in the outer implanted holes 20. Then, on the bristle surface 5, a first outer tuft group 24a is constituted by 15 outer tufts 22 provided along the side edge 6 of the head portion 4, and a second outer tuft group 24b is constituted by 15 outer tufts 22 provided along the side edge 7 of the head portion 4. The plurality of outer implanted holes 20 are arranged in a staggered pattern such that the positions of the outer implanted holes 20 adjacent to each other in the direction of the axis O are shifted in the width direction of the brush head portion 4. Therefore, the outer tufts 22 are arranged in a staggered pattern in which the positions of the outer tufts 22 adjacent to each other in the direction of the axis O are shifted in the width direction of the head portion 4. The hair length t1, which is the length of inner tuft 12 on hair-planted surface 5, is formed longer than the hair length t2, which is the length of outer tuft 22 on hair-planted surface 5.

An inner hair-planted region 11 indicating a region where an inner hair bundle group 14 is provided is formed on the hair-planted surface 5. The inner implanted hair region 11 is a region surrounded by a loop line connecting outer edges of the inner implanted holes 10 implanted with the inner tufts 12 located at the outermost periphery of the inner tuft group 14. In addition, the loop line thereof forms a common tangent line between the adjacent inner implant holes 10.

On the hair-planted surface 5, a first outer hair-planted region 21a indicating a region where the first outer hair bundle group 24a is provided is formed. First outer hair-attachment region 21a is a region surrounded by a loop line connecting the outer edges of outer hair-attachment holes 20 into which outer hair bundles 22 constituting first outer hair-bundle group 24a are implanted. In addition, this loop line constitutes a common tangent line between adjacent outer implantation holes 20 in first outer tuft group 24 a.

In addition, a second outer hair-planted region 21b indicating a region where the second outer hair bundle group 24b is provided is formed on the hair-planted surface 5. The second outer hair implantation region 21b is a region surrounded by a loop line connecting outer edges of the outer hair implantation holes 20 implanted with the outer hair bundles 22 constituting the second outer hair bundle group 24 b. In addition, the loop line constitutes a common tangent line between the adjacent outer implantation holes 20 in the second outer hair bundle group 24 b. The first outer hair-planted region 21a and the second outer hair-planted region 21b constitute an outer hair-planted region 21 in which a plurality of outer hair bundles 22 are planted with the inner hair bundles 12 interposed therebetween in the width direction of the head portion 4.

The material of the handle body 2 may be determined according to the rigidity, mechanical properties, and the like required for the toothbrush 1, and the mechanical properties required for the toothbrush 1 can be obtained by using a high-hardness resin having a flexural modulus of elasticity (JIS K7203) in the range of 500 to 3000MPa, for example. Examples of the high-hardness resin include polypropylene (PP), polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT), Polystyrene (PS), acrylonitrile-butadiene-styrene resin (ABS), Cellulose Propionate (CP), polyarylate, polycarbonate, and acrylonitrile-styrene resin (AS), and 1 or more of them can be used.

The size of the brush head portion 4 may be determined by the maximum length of the inner and outer bristle-implanted

regions

11 and 21 in the width direction of the brush head portion 4, the operability in the oral cavity, and the like, and the width (maximum width) W may be 14mm or more, for example, 14 to 18mm, and the thickness T may be 4 to 8 mm.

Preferably, the maximum length L in the width direction of the head 4 of all the bristle-implanted regions including the inner bristle-implanted region 11 and the outer bristle-implanted region 21 is 12.0mm to 16.0 mm. When the maximum length L of all the hair-planted regions is less than 12.0mm, there is a possibility that a sufficient massage effect cannot be obtained. When the maximum length L of all the hair-planted regions exceeds 16.0mm, the resistance when the head 4 is inserted into the oral cavity may increase, and the operability may decrease.

Further, as shown in the toothbrush 1 shown in fig. 1, when the inner tufts 12 and the outer tufts 22 are arranged in a staggered manner, the maximum length L in the width direction of the head 4 of all the bristle-implanted regions including the inner bristle-implanted region 11 and the outer bristle-implanted region 21 is more preferably 12.0mm to 15.0 mm. When the inner tufts 12 and the outer tufts 22 are arranged in a staggered pattern, the inner tufts 12 and the outer tufts 22 can be provided in the head portion 4 at a high density, and therefore, even if the maximum length is 15.0mm or less, a massaging effect on the gums and good cleaning performance for the neck of the teeth can be ensured.

Preferably, the maximum length of the inner bristle-implanted region 11 in the width direction of the head 4 is 4.0mm to 5.5 mm. When the maximum length of the inner bristle-implanted region 11 in the width direction is less than 4.0mm, there is a possibility that good cleaning performance for the neck portion of the tooth cannot be sufficiently obtained and the feeling of the brush head 4 entering the neck portion of the tooth becomes thin. When the maximum length of the inner implanted hair region 11 in the width direction exceeds 5.5mm, it is difficult to secure the length of the outer bundle of hairs 22, and the massage effect on the gum may not be sufficiently secured.

Preferably, the maximum length of the outer bristle-implanted region 21 in the width direction of the head portion 4, i.e., the sum of the maximum length of the first outer bristle-implanted region 21a and the maximum length of the second outer bristle-implanted region 21b in the width direction of the head portion 4 is 6.5mm to 9.5 mm. When the maximum length of the outer bristle-implanted region 21 in the width direction is less than 6.5mm, there is a possibility that a sufficient massaging effect on the gum and a good cleaning performance on the tooth neck portion cannot be secured. When the maximum length of the outer bristle-implanted region 21 in the width direction exceeds 9.5mm, the outer bristle bundle 22 may be strongly touched to the gum, and may be damaged by gentle touch.

When the inner tufts 12 and the outer tufts 22 are arranged in a staggered pattern, the maximum length of the outer hair-planted region 21 in the width direction of the head 4 is preferably 7.0mm to 9.5 mm. When the inner tufts 12 and the outer tufts 22 are arranged in a staggered pattern, the inner tufts 12 and the outer tufts 22 can be provided in the head portion 4 at a high density, respectively, so that the maximum length of the outer bristle-implanted region 21 can be set to 7.0mm or more, and the massaging effect on the gums and the good cleaning performance on the neck of the teeth can be improved.

The diameter D1 of the inner implanted pores 10 is determined by the diameter of the inner tufts 12 (i.e., the diameter of the cross section perpendicular to the longitudinal direction of the inner tufts 12), and may be, for example, 1.0 to 1.4 mm. In the present embodiment, the diameter D1 of all the inner implant holes 10 may be set to be substantially the same. By substantially the same is meant that all diameters D1 are included in the range of + -5%.

The diameter D2 of the outer implantation hole 20 may be determined according to the diameter of the outer tufts 22, and may be, for example, 1.4 to 1.8 mm. In the present embodiment, the diameter D2 of all the outer implant holes 20 may be set to be substantially the same. By substantially the same is meant that all diameters D2 are included in the range of + -5%.

The length t1 of the inner side bristles 12 can be determined by the material and thickness of the inner side bristles 13, and can be, for example, 6 to 15 mm. Preferably, tuft diameter d1 of inner tufts 12, i.e., the diameter of the cross section perpendicularly intersecting the longitudinal direction of inner tufts 12, is 1.0mm or more and 1.4mm or less. When the tuft diameter d1 of the inner tufts 12 is smaller than 1.0mm, the stiffness of the bristles of the inner tufts 12 becomes too low, the cleaning ability of the tooth neck portion becomes low, and the feeling of fullness when the tooth neck portion enters the brush head portion 4 becomes thin. When the tuft diameter d1 of the inner tufts 12 exceeds 1.4mm, the distal end portions of the inner tufts 12 are less likely to enter into the fine portions such as periodontal pockets and interdental portions, and the cleaning ability is lowered, and the contact feeling when the brush head portion 4 enters the neck portion becomes too strong. When the tuft diameter d1 of the inner tufts 12 is 1.0mm or more and 1.4mm or less, the feeling of the head 4 entering the neck of the tooth can be improved.

In the present embodiment, all of the inner tufts 12 may be set to have substantially the same tuft diameter d 1. By substantially the same is meant that all diameters d1 are included in the range of ± 5%.

The number of the inner bristles 13 corresponding to each 1 inner tuft 12 may be determined according to the bristle diameter of the inner bristles 13, and may be, for example, 10 to 40.

The tuft diameter D1 of the inner tufts 12 is substantially equal to the diameter D1 of the inner tuft hole 10, and is the diameter at the boundary with the tufting surface 5. Approximately the same means a difference within ± 5%.

The bristle density of the inner bristle group 14, i.e., the value obtained by dividing the total number of the inner bristles 13 constituting the inner bristle group 14 by the area of the inner bristle region 11 (inner bristle density), is not particularly limited, but is preferably 4 to 11 bristles/mm, for example²More preferably 6 to 9 pieces/mm². The density of the implanted hairs on the inner side is less than 4 hairs/mm²In this case, the inner side tufts 12 cannot support each other during brushing, and the bristle stiffness is lowered, thereby reducing the cleaning ability of the tooth neck. The density of the implanted hairs on the inner side exceeds 11 roots/mm²In this case, during brushing, the adjacent inner tufts 12 interfere with each other to an increased extent, and movement of the inner tufts 12 such as flexure is excessively suppressed, thereby preventing the inner bristles 13 from entering the tooth neck.

The inner bristles 13 are ST bristles (super tapered bristles) whose bristle tips are set to be tapered. The diameter of the inner bristles 13 may be determined by the material of the inner bristles 13, and may be, for example, 6 to 9 mils (1 mil: 1/1000 inch: 0.025 mm). When the thickness is 6mil or more, the stiffness of the bristles for cleaning the neck part of the tooth can be secured, and when the thickness is 9mil or less, the flexibility for alleviating the irritation to the gum can be secured. The bristle diameter of the ST bristles is the diameter of the base.

The length of the outer tufts 22 on the bristle surface 5, i.e., the bristle length t2, can be determined according to the material, thickness, etc. of the outer bristles 23, and can be, for example, 6 to 13 mm.

The difference t3 between t1 in the inner side tuft 12 and t2 in the outer side tuft 22 is preferably 2.0mm or less, more preferably 0.5 to 1.5 mm. When t1 is greater than t2, that is, when t1 of inner tuft 12 is greater than t2 of outer tuft 22, the cleaning ability of the tooth neck and the feeling of contact with the gum can be further improved. Further, by making the length of the inner bundle of bristles 12 on the bristle surface 5 longer than the length of the outer bundle of bristles 22 on the bristle surface 5, the feeling of fullness when the brush head portion 4 enters the neck portion of the tooth can be improved.

Preferably, tuft diameter d2 of outer tufts 22, i.e., the diameter of the cross-section perpendicularly intersecting the longitudinal direction of outer tufts 22, is 1.4mm or more and 1.8mm or less. When the tuft diameter d2 of the outer tufts 22 is smaller than 1.4mm, the contact area with the gum is small, and a sufficient massage effect may not be obtained. When the tuft diameter d2 of the outer tufts 22 exceeds 1.8mm, in particular, when the head portion 4 is widened, the interference of the outer tufts 22 is large, and the bristles are not deflected. Therefore, only the front ends of the outer tufts 22 come into contact with the gums, and efficient massage is difficult. In addition, when the tuft diameter d2 of outer tufts 22 exceeds 1.8mm, there is a possibility that: the hair length on the outer peripheral side of the tufts becomes lower than the hair length at the center of the tufts, and becomes a mountain-shaped tuft, and only the hair tip of the bristles near the center of the tuft contacts the gum, resulting in inefficiency of the massage.

When the tuft diameter d2 of the outer tufts 22 exceeds 1.8mm, the pressure applied to the gum from the distal ends of the outer tufts 22 cannot be dispersed during brushing, and the stimulation to the gum becomes strong, resulting in a decrease in the contact feeling to the gum. When the tuft diameter d2 of the outer tufts 22 exceeds 1.8mm, the interference between the outer bristles 23 and the other outer bristles 23 constituting the same outer tufts 22 becomes too large, the freedom of movement is impaired, and the feeling of gentle contact is reduced.

In the present embodiment, all of outer tufts 22 may have tuft diameter d2 set to be substantially the same. By substantially the same is meant that all diameters d2 are included in the range of ± 5%. The number of the outer bristles 23 per 1 outer bristle bundle 22 may be determined according to the bristle diameter of the outer bristles 23, and may be, for example, 40 to 100.

Moreover, tuft diameter D2 of outer tufts 22 is substantially the same as diameter D2 of outer tuft hole 20, as it is at the boundary with tufting surface 5.

The bristle density of the first outer bristle group 24a, i.e., the value obtained by dividing the total number of outer bristles 23 constituting the first outer bristle group 24a by the area of the first outer bristle region 21a, is preferably 10 bristles/mm²More preferably 12 roots/mm²The above. The bristle density of the first outer side tuft group 24a is less than 10/mm²In this case, it becomes difficult to disperse the pressure applied to the gum from the distal end of the outer bundle 22 during brushing.

The flocking density of the second outer side bundle group 24b, that is, the value obtained by dividing the total number of outer side bristles 23 constituting the second outer side bundle group 24b by the area of the second outer side flocking region 21b is the same as the flocking density of the first outer side bundle group 24 a.

The bristle density of the first outer tuft group 24a may be the same as or different from that of the second outer tuft group 24 b. However, in view of ensuring a gentle contact feeling to the gums of both the upper, lower, left, and right sides in the oral cavity during brushing, it is preferable that the bristle density of the first outer bristle group 24a is substantially the same as the bristle density of the second outer bristle group 24 b. The substantially same means that the ratio of [ the flocking density of the first outer side tuft ]/[ the flocking density of the second outer side tuft ] is 0.95 to 1.05.

The total number of outer bristles 23 constituting the second outer tuft group 24b is the same as the total number of outer bristles 23 constituting the first outer tuft group 24 a. The total number of outer bristles 23 constituting the first outer tuft group 24a may be the same as or different from the total number of outer bristles 23 constituting the second outer tuft group 24 b. However, from the viewpoint of ensuring a gentle contact feeling to the gums of both the upper, lower, left, and right sides in the oral cavity during brushing, the total number of outer bristles 23 constituting the first outer tuft group 24a is preferably substantially the same as the total number of outer bristles 23 constituting the second outer tuft group 24 b. The substantially same means that the ratio of [ the total number of outer bristles constituting the first outer bristle group ]/[ the total number of outer bristles constituting the second outer bristle group ] is 0.95 to 1.05.

The value (outer bristle density) obtained by dividing the sum of the total number of outer bristles 23 constituting the first outer tuft group 24a and the total number of outer bristles 23 constituting the second outer tuft group 24b by the sum of the area of the first outer bristle region 21a and the area of the second outer bristle region 21b is preferably, for example, 10 bristles/mm²More preferably 12 roots/mm²The above. The density of the outside planted hair is less than 10 roots/mm²In this case, it becomes difficult to disperse the pressure applied to the gum from the distal end of the outer bundle 22 during brushing.

Preferably, the ratio of the flocking density represented by [ outer flocking density ]/[ inner flocking density ] is 1.4 or more and 2.5 or less. When the flocking density ratio is less than 1.4, there is a concern that: the pressure dispersion of the outer side tufts is reduced to lower the soft contact feeling, and the density of the inner side tufts is too high to lower the cleanability of the tooth neck portion. When the bristle density ratio exceeds 2.5, the bristle rigidity of the inner tuft group 14 is lowered, and the cleanability of the tooth neck portion is lowered. That is, when the amount is within the above range, both a soft contact feeling to the gum and a good cleaning property of the tooth neck portion can be achieved.

When the inner tufts 12 and the outer tufts 22 are arranged in a staggered pattern, the ratio of the flocking density represented by [ outer flocking density ]/[ inner flocking density ] is preferably 1.4 or more and 2.0 or less. When the inner tufts 12 and the outer tufts 22 are arranged in a staggered pattern, the inner tufts 12 and the outer tufts 22 can be provided in the head portion 4 at high density, respectively, and therefore, even if the bristle density ratio is 2.0 or less, a soft contact feeling and good cleanability of the neck portion can be sufficiently ensured.

The outer bristles 23 are ST bristles (super tapered bristles) with tapered bristle tips, like the inner bristles 13. The diameter of the outer bristles 23 may be determined by the material of the outer bristles 23, and may be, for example, 4 to 7 mils (1 mil: 1/1000 inch: 0.025 mm). When the thickness is 4mil or more, sufficient self-standing property cannot be obtained, and when the thickness is 7mil or less, stimulation to the gum can be sufficiently alleviated. Further, it is preferable that the bristles of the outer bristles 23 have a smaller diameter than the bristles of the inner bristles 13. With such a configuration, the inner bristles 13 can improve the cleaning performance of the tooth neck portion while alleviating irritation to the gum by the outer bristles 23 which easily contact the gum during brushing.

According to the present embodiment, since the inner bristle-implanted region 11 having a maximum length in the width direction of 4.0mm to 5.5mm is provided at substantially the center of the bristle-implanted surface 5 in the width direction of the head 4, outer bristle-implanted regions 21 having a maximum length in the width direction of 6.5mm to 9.5mm are provided on both sides of an inner bristle-implanted region 11 in the width direction of the head 4, the maximum length of all the bristle-implanted regions in the width direction is 12.0mm to 16.0mm, a tuft diameter d2 of the outer tufts 22 is 1.4mm to 1.8mm, a tuft diameter d1 of the inner tufts 12 is 1.0mm to 1.4mm, therefore, the inner tufts 12 and the outer tufts 22 arranged in a wide range can provide the gum with a soft massaging feeling of soft contact, and can ensure a solid feeling of the brush head portion 4 entering the neck of the tooth and good cleaning performance.

According to the present embodiment, since the bristle density ratio represented by the ratio of the outer bristle density to the inner bristle density is 1.4 or more and 2.5 or less, the outer bristle

groups

24a and 24b, which easily contact the gum during brushing, have a high bristle density, and the pressure applied to the gum from the distal end of the outer bristle 22 is dispersed, whereby stimulation to the gum can be alleviated, so that a soft and gentle contact feeling can be obtained, and the neck part of the tooth can be cleaned satisfactorily by the inner bristles 13 constituting the inner bristle group 14 having a low bristle density.

According to the present embodiment, since the inner tufts 12 are set to have a longer bristle length than the outer tufts 22, the feeling of reality when the head 4 is inserted into the neck can be improved, and the inner bristles 13 can easily be inserted into the periodontal pocket or interdental portion, thereby further improving the cleanability of the neck.

According to the present embodiment, when the inner tufts 12 and the outer tufts 22 are arranged in a staggered manner, the inner tufts 12 and the outer tufts 22 can be provided on the bristle surface 5 at a higher density than in the case where the inner tufts 12 and the outer tufts 22 are arranged in a lattice pattern in which the positions between adjacent tufts in the axis O direction are the same in the width direction of the head portion 4, so that even if the maximum length of the entire bristle field is small compared to a toothbrush in which the inner tufts 12 and the outer tufts 22 are arranged in a lattice pattern, a soft massaging effect with respect to the soft contact feeling of the gums, a feeling of penetration of the head portion 4 into the neck portion of the teeth, and good cleaning performance can be obtained.

The present invention is not limited to the above-described embodiments. In the above embodiment, the inner tufts are set to be approximately cylindrical, but may be elliptical cylindrical in plan view, or polygonal cylindrical (polygonal cylindrical) in plan view, such as triangular, quadrangular, pentagonal, etc. In addition, when the shape of the inner tufts is set to be other than approximately cylindrical, the tuft diameter is defined as the diameter of a perfect circle circumscribing the shape in plan view.

The outer tufts may have an elliptical columnar shape in plan view, or may have a polygonal columnar shape (polygonal columnar shape) such as a triangle, a quadrangle, or a pentagon in plan view, as in the case of the inner tufts.

Although the inner implanted pores are formed in a bottomed cylindrical shape in the above embodiment, the shape of the inner implanted pores may be determined according to the shape of the inner bundles, and for example, the inner implanted pores may be formed in a bottomed cylindrical shape having an elliptical shape in plan view, or may be formed in a bottomed polygonal cylindrical shape (polygonal cylindrical shape) having a triangular shape, a quadrangular shape, a pentagonal shape, or the like in plan view. The outer implanted holes may be closed-end cylindrical shapes having an elliptical shape in plan view, or closed-end polygonal cylindrical shapes (polygonal cylindrical shapes) having a triangular shape, a quadrangular shape, a pentagonal shape, or the like in plan view, as in the inner implanted holes.

Although the diameters of all the inside implanted pores are set to be substantially the same in the above-described embodiment, the present invention is not limited to this, and the diameters of all the inside implanted pores may be different from each other, and the diameter of a part of the inside implanted pores may be different from the diameters of other inside implanted pores. In the above-described embodiment, all the outside implanted pores have substantially the same diameter, but the present invention is not limited to this, and all the outside implanted pores may have different diameters, and some of the outside implanted pores may have different diameters from those of other outside implanted pores.

Although the inner bristles are set as the ST bristles in the above embodiment, the present invention is not limited thereto, and for example, the inner bristles may have a uniform diameter throughout the entire length thereof, or the tips may be set as a hemispherical surface or a surface parallel to the bristle surface. Among them, from the viewpoint of easy entry into the periodontal pocket or the interdental portion, it is preferable that the inner bristles of a part of the inner tufts are ST bristles or tapered bristles, and more preferable that the inner bristles of all of the inner tufts are ST bristles or tapered bristles. Further, as with the inner bristles, the outer bristles may have a uniform diameter throughout their length, or the tips may be hemispherical or parallel to the bristle surface. However, from the viewpoint of making the contact feeling to the gum gentle, it is preferable that the outer bristles of a part of the outer tufts are ST bristles or tapered bristles, and more preferably all the outer bristles of the outer tufts are ST bristles or tapered bristles. Alternatively, only one of the inner bristles and the outer bristles may be formed of ST bristles or tapered bristles.

Although the inner bristles and the outer bristles are set to be tapered bristles having an approximately cylindrical shape in the above embodiments, the inner bristles and the outer bristles may have an elliptical cylindrical shape in a plan view, a polygonal columnar shape (polygonal columnar shape) having a triangular shape, a quadrangular shape, a pentagonal shape, or the like in a plan view, or the like. When the inner bristles or the outer bristles have a shape other than a substantially cylindrical shape, the bristle diameter is defined as the diameter of a perfect circle circumscribing the shape in plan view.

Although the hair length of the inner tufts is set to be longer than the hair length of the outer tufts in the above-described embodiments, for example, the hair length of the inner tufts and the hair length of the outer tufts may be the same, i.e., the difference in hair length may be 0mm, and the hair length of the inner tufts may also be shorter than the hair length of the outer tufts. The lengths of the inner and outer tufts may be set so that the tip of the main tuft is connected to the concave-convex surface of the handle body in which the peak and valley portions are repeated in the axial direction.

Among them, from the viewpoint of cleaning the tooth neck portion satisfactorily, the inner side tufts preferably have longer hair lengths than the outer side tufts.

Although the inner tuft group is constituted by 27 inner tufts in the above embodiment, the number of inner tufts constituting the inner tuft group may be 26 or less, or may be 28 or more.

Although the first outer tuft group or the second outer tuft group is constituted by 15 outer tufts in the above embodiment, for example, the number of outer tufts constituting the first outer tuft group or the second outer tuft group may be 14 or less, or may be 16 or more.

The number of outer tufts constituting the first outer tuft group may be the same as or different from the number of outer tufts constituting the second outer tuft group.

Although the inner tufts and the outer tufts are arranged in a staggered pattern in the axial direction of the handle body in the above-described embodiment, the present invention is not limited to this, and for example, the inner tufts 12 and the outer tufts 22 may be arranged in a lattice pattern as in the toothbrush 1A shown in fig. 3.

Although the outer tufts are implanted outside the inner tuft region in the above embodiments, the outer tufts may be provided so as to sandwich the inner tufts, for example, a part of the outer tufts may be located in the inner tuft region.

Although the tuft diameters of all the inner tufts are set to be substantially the same in the above embodiment, for example, the tuft diameters of the inner tufts may be different from each other. Among them, from the viewpoint of appropriately controlling the stiffness of the bristles of the inner side tufts, it is preferable that all the inner side tufts have substantially the same tuft diameter. In addition, although the tuft diameters of all the outer tufts are set to be substantially the same in the above embodiment, for example, the tuft diameters of the outer tufts may be different from each other. Among them, it is preferable that all the outer tufts have substantially the same tuft diameter from the viewpoint of making uniform the pressure applied to the gum from the distal end of the outer tuft on each outer tuft and making the contact feeling of the entire outer tuft group soft.

Examples

(evaluation method)

The toothbrushes of the respective examples were evaluated for "feeling of massage" (feeling of contact) and cleanability of the tooth neck portion by the following methods. The cleanability of the tooth neck portion was evaluated by "the feeling of tooth neck penetration" and "the cleanability of the tooth neck portion".

< evaluation of massage feeling >

The panelists 10 evaluated the massaging feeling of the gum using the toothbrushes of the respective examples according to the following evaluation criteria. The average score of the 10 persons was "very good" at 2.5 or more, the average score was "good" at 2.0 or more and less than 2.5, the average score was "Δ" at 1.5 or more and less than 2.0, and the average score was "x" at less than 1.5.

Reference to evaluation

And 3, dividing: the massaging feeling of the gum is strongly felt.

And 2, dividing: the massaging feeling of the gum is felt.

1 minute: the massaging feeling of the gum is not so much felt.

0 minute: no massaging sensation of the gums was felt.

< evaluation of the sensation of penetration of the neck of a tooth >

With respect to the sensation of penetration of the tooth neck portion, the examiner 10 evaluated the sensation of penetration of the tooth neck portion using the toothbrushes of each example according to the following evaluation criteria. The average score of the 10 persons was "very good" at 2.5 or more, the average score was "good" at 2.0 or more and less than 2.5, the average score was "Δ" at 1.5 or more and less than 2.0, and the average score was "x" at less than 1.5.

Reference to evaluation

And 3, dividing: the tactile sensation that the hair front reaches the gap between the teeth and the gum is strongly felt.

And 2, dividing: the tactile sensation of the hair tips reaching the gap between the teeth and gums is felt.

1 minute: the tactile sensation that the hair front reaches the gap between the teeth and the gum is less felt.

0 minute: the tactile sensation that the hair front reaches the gap between the teeth and the gum is not felt.

< evaluation of cleaning force for tooth neck portion >

With respect to the tooth neck cleaning force, the following model cleaning force test was performed using the toothbrushes of the examples and comparative examples. First, the following are prepared: a red paint (Sakura) white board marker #19 red, manufactured by Sakura Color Products Corporation) was applied as model tartar to the neck of the first molar tooth on the right cheek side of an adult palate model (500AU, manufactured by japan). The teeth on which model tartar was formed were cleaned by pressing the toothbrush at 45 degrees with a load of 200g while reciprocating 10 times in a stroke of 20mm in a direction connecting the distal end of the head portion and the proximal end of the head portion. After the cleaning, the tartar removal rate was measured by the following method.

Calculation of dental calculus removal Rate

The model tartar occupation area of the neck of the first large molar was measured by image analysis before the cleaning power test, and after the cleaning power test, the model tartar occupation area of the same site was measured again and calculated according to the following expression (1). The calculated plaque removal rates were classified according to the following criteria, and the tooth neck cleaning power was evaluated. More than 70% was designated as "+", more than 50% and less than 70% was designated as ". smallcircle", more than 30% and less than 50% was designated as "Δ", and less than 30% was designated as "X".

Tartar removal rate (%) ((tartar occupied area before cleaning power test-tartar occupied area after cleaning power test)/(tartar occupied area before cleaning power test)) × 100 … (1)

(examples 1 to 3 and comparative examples 1 to 6)

According to the specification shown in fig. 4, a toothbrush with ST bristles (made of PBT) implanted therein was manufactured in the same manner as the toothbrush 1 of fig. 1. The toothbrush 1 includes: an inner side hair bundle group composed of inner side hair bundles implanted in a staggered manner, and a pair of outer side hair bundle groups composed of outer side hair bundles implanted in a staggered manner respectively and clamping the inner side hair bundle group. The first outer tuft group and the second outer tuft group are each composed of the same number of outer tufts.

In the table, "the number of inner bristles per inner tuft" means the number of inner bristles constituting 1 inner tuft, and "the number of outer bristles per outer tuft" means the number of outer bristles constituting 1 outer tuft. The specification relating to the outer side tuft group is referred to as a combination of the first outer side tuft group and the second outer side tuft group. The obtained toothbrushes of the respective examples were evaluated for the feeling of massaged, the feeling of entry of the tooth neck, and the cleaning power of the tooth neck.

(examples 4 to 6)

According to the specifications shown in fig. 4, a toothbrush with ST bristles (made of PBT) implanted therein was manufactured in the same manner as the toothbrush 1A of fig. 3. The toothbrush 1A includes: an inner side hair bundle group composed of inner side hair bundles implanted in a grid shape, and a pair of outer side hair bundle groups composed of outer side hair bundles implanted in a grid shape respectively and sandwiching the inner side hair bundle group. The first outer tuft group and the second outer tuft group are each composed of the same number of outer tufts. The obtained toothbrushes of the respective examples were evaluated for the feeling of massaged, the feeling of entry of the tooth neck, and the cleaning power of the tooth neck.

As shown in fig. 4, in examples 1 to 6 to which the present invention was applied, the evaluations of the massage feeling, the tooth neck portion entry feeling, and the tooth neck portion cleaning power were all "excellent" or "o".

On the other hand, in comparative example 1 in which the tuft diameter of the outer tufts is 2.0mm and the maximum length of the outer bristle-implanted region is 9.9mm, the neck portion entering feeling is "o", the cleaning power of the neck portion is "excellent", but the massaging feeling is "x".

In comparative example 2 in which the outer tufts have a tuft diameter of 1.1mm and the maximum length of the outer bristle-implanted region is 6.3mm, the "very good" sensation of entry into the tooth neck and the "o" sensation of cleaning force of the tooth neck were obtained, but the "x" sensation of massage was obtained.

In comparative example 3 in which the inner tufts have a tuft diameter of 1.5mm and the maximum length of the inner bristle-implanted region of 5.6mm, the massage feeling was "o", but the tooth neck penetration feeling and the tooth neck cleaning force were "Δ".

In comparative example 4 in which the inner tufts have a tuft diameter of 0.9mm and the maximum length of the inner bristle-implanted region is 3.8mm, the feeling of solid massage and the feeling of solid entry of the tooth neck are "o", but the cleaning force of the tooth neck is "x".

In comparative example 5 in which the bristle density ratio was 3.03, the massage feeling was "very excellent", but the neck part entering feeling and the neck part cleaning power were "x".

In comparative example 5 in which the bristle density ratio was 1.25, the massage solid feeling, the neck penetration solid feeling, and the tooth neck cleaning power were all "Δ".

From the above results, it is understood that the present invention provides a toothbrush which satisfies both a massaging feeling accompanied by a soft contact feeling to the gum, a feeling of penetration of the tooth neck, and a cleaning property of the tooth neck.

Although preferred embodiments of the present invention have been described above with reference to the drawings, the present invention is not necessarily limited to these examples. The various shapes, combinations, and the like of the respective components shown in the above examples are merely examples, and various modifications can be made based on design requirements and the like within a range not departing from the gist of the present invention.

Industrial applicability of the invention

The present invention may be applied to toothbrushes.

Claims

1. A toothbrush comprising a handle body having a brush head portion at the tip thereof, and tufts each having bristles implanted in a plurality of implantation holes formed in a bristle implantation surface of the brush head portion,

the hair-planting surface is provided with an inner hair-planting area and an outer hair-planting area:

in the inner hair planting region, a plurality of inner hair bundles are arranged in parallel in the axial direction of the handle body and planted in the approximate center of the width direction which is vertically crossed with the axial line,

a plurality of outer tufts are implanted in the outer tuft region with the inner tufts interposed therebetween in the width direction,

the outer side tufts are arranged in a staggered pattern in which positions between adjacent tufts in the axial direction are shifted in the width direction, or in a lattice pattern in which positions between adjacent tufts in the axial direction are in the width direction, and a first outer side tuft group and a second outer side tuft group among the outer side tufts each have outer side tufts arranged in 2 or 3 rows in the width direction, and the maximum length of all of the hair-planted regions in which the plurality of inner side tufts and the plurality of outer side tufts are implanted in the width direction is 12.0mm or more and 16.0mm or less,

the maximum length of the outer hair-planted region in the width direction is 6.5mm to 9.5mm,

the maximum length of the inner side hair-planted region in the width direction is more than 4.0mm and less than 5.5mm,

the diameter of the outer side hair bundle is more than 1.4mm and less than 1.8mm,

the diameter of the inner side hair bundle is more than 1.0mm and less than 1.4mm,

when a value obtained by dividing the total number of bristles constituting the plurality of outer side tufts by the area of the outer side bristle-implanted region is defined as an outer side bristle-implanted density, and a value obtained by dividing the total number of bristles constituting the plurality of inner side tufts by the area of the inner side bristle-implanted region is defined as an inner side bristle-implanted density,

the ratio of the outer-side bristle density to the inner-side bristle density is 1.4 to 2.5.

2. The toothbrush according to claim 1, wherein the outer tufts are arranged in a staggered pattern with positions of adjacent tufts in the axial direction being offset in the width direction, and wherein first and second outer tuft groups among the outer tufts each have outer tufts arranged in 3 rows in the width direction; alternatively, the outer tufts may be arranged in a lattice shape in the width direction at positions between adjacent tufts in the axial direction, and each of the first outer tuft group and the second outer tuft group of the outer tufts may have 2 rows of outer tufts arranged in the width direction.

3. The toothbrush of claim 1 or 2, wherein the length of the inner tufts on the bristle face is longer than the length of the outer tufts on the bristle face.

4. The toothbrush according to claim 1 or 2, wherein at least one of the inner and outer tufts includes bristles having a diameter that gradually decreases toward a bristle tip.

5. The toothbrush according to claim 1 or 2, wherein the inner tufts are arranged in a staggered pattern or a lattice pattern in which the positions of the tufts adjacent to each other in the axial direction are shifted in the width direction.

6. The toothbrush of claim 1 or 2,

the inner side tufts and the outer side tufts are arranged in a staggered pattern in which positions of adjacent tufts in the axial direction are shifted in the width direction,

the maximum length of all the hair-planted regions in the width direction is 12.0mm to 15.0mm,

the maximum length of the outer hair-planted region in the width direction is 7.0mm to 9.5mm,

the ratio of the outer-side bristle density to the inner-side bristle density is 1.4 to 2.0.