CN111297042B

CN111297042B - Tooth brush

Info

Publication number: CN111297042B
Application number: CN202010118515.7A
Authority: CN
Inventors: 金丸直史; 龟井诚一
Original assignee: Lion Corp
Current assignee: Lion Corp
Priority date: 2016-03-09
Filing date: 2017-03-09
Publication date: 2021-07-06
Anticipated expiration: 2037-03-09
Also published as: MY197050A; SG10202008599VA; KR20200090937A; KR102418463B1; KR102418459B1; WO2017155045A1; TWI753888B; CN108778049A; KR20180120144A; SG11201807594RA; SG10202008598RA; SG10202008614TA; CN111297042A; CN108778049B; CN111227498B; TW201733492A; KR102418461B1; KR20200090938A; CN111227498A

Abstract

A toothbrush with a thin head part, which can be operated well, is provided. The toothbrush is provided with a head part (110) which is arranged at the front end side and implanted with hair bundles on a hair implanting surface (111), a neck part (120) which is arranged to extend to the rear end side of the head part, and a handle part (130) which is arranged to extend to the rear end side of the neck part. The thickness of the head is 2.0-4.0 mm. The neck part is formed as follows: the minimum value of the width in the direction parallel to the hair-planted surface and perpendicular to the longitudinal direction of the handle portion is 3.5mm or more and 4.5mm or less, and the width is constant or gradually increased from the position of the minimum value toward the rear end side direction. When the width of the neck part at the position deviated from 10mm from the minimum value in the neck part parallel to the hair-planted surface toward the rear end side is W mm and the thickness of the neck part in the direction perpendicular to the hair-planted surface is D mm, the value obtained from D/W is 0.7-2.5 inclusive, and the deflection coefficient M (mm) is⁴)＝W×D³Is 165mm⁴Above, 625mm⁴The following.

Description

Tooth brush

The application is a divisional application of an invention patent application with application date of 2017, 03 and 09, application number of 201780016556.1 and invention name of 'toothbrush'.

Technical Field

The present invention relates to toothbrushes.

The present application claims priority based on Japanese patent application No. 2016-.

Background

In patent documents 1 to 3, toothbrushes having a head with a reduced thickness have been proposed from the viewpoint of oral operability and the like. When the thickness of the head portion is reduced, there is a problem that the strength is reduced. For this reason, a resin having high strength such as polyacetal resin (POM) is used. In particular, when a flat wire made of metal is driven into a head made of resin or a flat wire type bristle fixing member, the bristle fixing strength and the folding strength of the head may be insufficient.

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent laid-open No. Hei 7-143914

[ patent document 2] Japanese patent application laid-open No. 2011-

[ patent document 3] Japanese patent laid-open publication No. 2011-

Disclosure of Invention

[ problems to be solved by the invention ]

After the research, the inventor discovers that: in the above toothbrush, if the neck portion connecting the head portion and the grip portion is thick, the effect of improving the oral cavity operability due to the head portion becoming thin is impaired. In particular, if the neck portion is widened, not only does the operability deteriorate further, but also the head portion is not noticeably thin in appearance, and the impression of the product is also impaired. However, when the neck portion is narrowed, excessive bending may be caused, and operability may be disadvantageously caused. In addition, the strength needs to be further improved. In particular, the problem is more remarkable in the case of general-purpose resins such as polypropylene (PP) which are generally used for toothbrushes.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a toothbrush having a thin head portion, which can achieve good operability.

Means for solving the problems

The invention according to claim 1 provides a toothbrush characterized in that,

the hair-setting device is provided with a head part which is arranged at the front end side and has hair bundles implanted on a hair-setting surface, a neck part which is arranged to extend to the rear end side of the head part, and a handle part which is arranged to extend to the rear end side of the neck part, wherein the thickness of the head part is 2.0-4.0 mm,

the neck portion is formed as: a minimum value of a width in a direction parallel to the hair-planted surface and perpendicular to a longitudinal direction of the grip portion is 3.5mm or more and 4.5mm or less, the width is constant or gradually increased from a position of the minimum value toward a rear end side,

when the width at a position shifted from the position of the minimum value in the neck portion by 10mm toward the rear end side in parallel with the hair-planted surface is W mm and the thickness in a direction perpendicular to the hair-planted surface is D mm,

a value obtained from D/W is 0.7 to 2.5 inclusive,

flexural modulus M (mm)⁴)＝W×D³Is 165mm⁴Above, 625mm⁴The following.

In the toothbrush according to one embodiment of the present invention, the neck portion is formed of a resin material, and the resin material has a flexural modulus of elasticity of 1000MPa to 2200 MPa.

In the toothbrush according to one embodiment of the present invention, the neck portion is formed of a polypropylene resin.

[ Effect of the invention ]

According to the present invention, a toothbrush capable of providing good oral operability even when a general-purpose resin is used can be provided.

Drawings

FIG. 1 is a view showing an embodiment of the present invention, and is a plan view of a toothbrush 11.

Fig. 2 is a side view of the above-described toothbrush 11.

Fig. 3 is a plan view of the front end side of the toothbrush 11 in an enlarged manner.

FIG. 4 is a side view of the front end side of the enlarged toothbrush 11.

Fig. 5A is a plan view of a toothbrush according to an embodiment of the present invention.

FIG. 5B is a side view of a toothbrush according to an embodiment of the present invention.

FIG. 6A is a diagram for explaining a method of measuring the amount of deflection of the head.

FIG. 6B is a diagram for explaining a method of measuring the amount of deflection of the head.

[ description of symbols ]

11 … toothbrush, 12 … handle body, 110 … head, 111 … hair-planting surface, 120 … neck, 130 … handle part

Detailed Description

Hereinafter, embodiments of a handle body of a toothbrush and a toothbrush according to the present invention will be described with reference to fig. 1 to 4.

The following embodiment is an embodiment showing the present invention, and is not intended to limit the present invention, and may be arbitrarily changed within the scope of the technical idea of the present invention. In the following drawings, scales, numbers, and the like of actual structures are different from those of the structures in order to make the structures easy to understand.

Fig. 1 is a plan view of a toothbrush 11. Fig. 2 is a side view of toothbrush 11. Fig. 3 is an enlarged plan view of the front end side of the toothbrush 11. Fig. 4 is an enlarged side view of the front end side of the toothbrush 11.

The toothbrush 11 of the present embodiment includes: a head portion 110 disposed at the front end and implanted with tufts 114 of bristles, a neck portion 120 provided to extend to the rear end side of the head portion 110, and a grip portion 130 provided to extend to the rear end side of the neck portion 120 (hereinafter, the head portion 110, the neck portion 120, and the grip portion 130 are collectively referred to as a grip body 12).

The handle body is integrally molded in a long shape as a whole, and may be obtained by injection molding using a resin as a material, for example.

Examples of the material of the handle body include resins having a flexural modulus of elasticity (JIS7171) of 1000MPa to 2200MPa, and examples thereof include polypropylene resins (PP), polyacetal resins (POM), polystyrene resins (PS), polyethylene terephthalate resins (PET), polybutylene terephthalate resins (PBT), acrylonitrile butadiene styrene resins (ABS), polyarylate resins, polycarbonate resins, and acrylonitrile styrene resins (AS). Among them, a polypropylene resin is preferable as a general-purpose resin from the viewpoint of more remarkable effects of the present invention and cost.

The above-mentioned resins may be used alone in 1 kind or in combination of 2 or more kinds.

In addition, the grip body may be partially or entirely covered with a soft resin such as an elastomer, for example, in order to improve the grippability. When a soft resin such as an elastomer is used, for example, polyolefin is preferable, and PP is more preferable, from the viewpoint of improving adhesiveness.

The head 110 has a flocked surface 111 on one side in the thickness direction (hereinafter referred to as an upper surface side). A plurality of implanted holes 112 are formed in the implanted surface 111, and tufts 114 of brush hairs are implanted in the implanted holes 112 (see fig. 2). In fig. 1, 3, and 4, illustration of tufts 114 is omitted.

The rear end side end portion of the head portion 110 in the present embodiment is defined by the following positions: when the distance from the outer edge of the hair-planting hole 112 disposed on the most distal side to the distal end of the head 110 is L11, the distance from the outer edge of the hair-planting hole 112 disposed on the most distal side to the rear side is L11. That is, as shown in fig. 3, the head 110 is disposed within a range 110A separated by a distance L11 from the outer edge of the hair-planting hole 112 located at both ends in the longitudinal direction. The position of the rear end side of the range 110A is a boundary P1' of the head 110 and the neck 120.

The distal end of the grip portion 130 is a finger contact portion, and the distal end of the finger contact portion is a boundary P2' between the neck portion 120 and the grip portion 130. The finger contact portion is demarcated by the following ridge lines: for example, a ridge line formed at an intersection of a surface on the side of the hair-planted surface 111 on the rear end side of the neck portion 120 and a surface on the side of the hair-planted surface 111 on the front end side of the grip portion 130, or a ridge line formed at an intersection of a surface on the opposite side of the hair-planted surface 111 on the rear end side of the neck portion 120 and a surface on the opposite side of the hair-planted surface 111 on the front end side of the grip portion 130. At this time, the boundary P2' between the neck portion 120 and the grip portion 130 is defined by the ridge line.

Further, in the case where the surface on the side of the hair-planted surface 111 on the rear end side of the neck portion 120 and the surface on the side of the hair-planted surface 111 on the front end side of the grip portion 130 are on the same plane without forming a ridge line, the finger contact portion is demarcated by a ridge line formed at an intersection of a side surface in the width direction on the rear end side of the neck portion 120 and a side surface in the width direction on the front end side of the grip portion 130. In this case, the boundary P2' between the neck portion 120 and the grip portion 130 is also defined by the ridge line.

For example, in the case of the handle body 12 of the embodiment in which the handle portion 130 is formed in the substantially circular arc shape convex toward the bristle surface 111 in the side view and the neck portion 120 is formed in the substantially circular arc shape concave toward the bristle surface 111 in the side view, the boundary P2' between the neck portion 120 and the handle portion 130 is defined as follows.

A curved surface 133 having a circular arc contour whose center position is arranged on the side opposite to the hair-planted surface 111 (the side lower than the grip portion 130 in fig. 2 and 4) and whose side of the hair-planted surface 111 is convex in a side view is formed on the hair-planted surface 111 side on the distal end side of the grip portion 130. Similarly, a curved surface 134 having a circular arc contour whose center position is disposed on the side opposite to the hair-planted surface 111 and whose side of the hair-planted surface 111 is convex in a side view is formed on the side opposite to the hair-planted surface 111 on the distal end side of the grip portion 130.

Further, on the side of the hair-planted surface 111 on the rear end side of the neck portion 120, a curved surface 123 having a circular arc contour whose center position is arranged on the hair-planted surface 111 (the upper surface side than the grip portion 130 in fig. 2 and 4) and whose side of the hair-planted surface 111 is recessed in a side view is formed. Similarly, a curved surface 124 having a circular arc contour whose center position is disposed on the hair-planted surface 111 and which is concave on the hair-planted surface 111 side in a side view is formed on the opposite side of the hair-planted surface 111 on the rear end side of the neck portion 120.

As the

curved surfaces

123 and 133 respectively proceed along the longitudinal direction of the grip portion 130, the intersection angle between the tangent line and the hair-planted surface 111 in the side view continuously changes, but the intersection between the

curved surfaces

123 and 133 intersects at an angle θ 1 at which the intersection angle between the tangent lines is not 0 or 180 degrees. Therefore, the ridge 131 is formed at the intersection of the curved surface 123 and the curved surface 133.

The

curved surfaces

124 and 134 also continuously change the intersection angle between the tangent line and the hair-planted surface 111 in the side view as the handle portion 130 advances in the longitudinal direction, but the intersection between the

curved surfaces

124 and 134 intersects at an angle θ 2 at which the intersection angle between the tangent lines is not 0 or 180 degrees. Therefore, the ridge 132 is formed at the intersection of the curved surface 124 and the curved surface 134. Therefore, the neck portion 120 and the grip portion 130 are connected by

curved surfaces

133 and 134 having a convex circular-arc contour on the side of the flocked surface 111 in a side view with one side of the

ridge lines

131 and 132 in the longitudinal direction and

curved surfaces

123 and 124 having a concave circular-arc contour on the side of the flocked surface 111 in a side view with the other side of the

ridge lines

131 and 132 in the longitudinal direction, thereby forming an approximate S shape in the side view.

The boundary of the rear end side of the neck portion 120 is defined by

ridges

131 and 132. Therefore, the rear end side of the

ridge lines

131 and 132 is a range 130A in which the handle 130 is arranged, and the neck portion 120 is arranged in a range 120A between the range 110A in which the head portion 110 is arranged and the range 130A in which the handle 130 is arranged.

The end of the grip portion 130 on the side of the flocked surface 111 (the end on the rear side of the ridge 131) serves as a finger contact portion. The user holds the grip portion 130 by touching the finger contact portion with the thumb, whereby the toothbrush 11 can be stably operated. The ridge 132 of the handle 130 is located at the rear end of the ridge 131 in the longitudinal direction. Therefore, the finger contact portion becomes thicker than the case where the ridge 132 is positioned on the tip side of the ridge 131, and the operation of the toothbrush 11 can be stabilized.

The length of the handle body 12 is not particularly limited, and may be, for example, 100 to 200 mm.

The width of the head 110, i.e., the width in the direction parallel to the bristle surface 111 and perpendicular to the longitudinal direction of the handle 130 (hereinafter simply referred to as "width") is not particularly limited, and is, for example, preferably 5 to 16mm, and more preferably 8 to 12 mm. When the value is equal to or higher than the lower limit, the area for implanting the hair bundle 114 can be sufficiently secured, and when the value is equal to or lower than the upper limit, the oral cavity operability can be further improved.

The length of the head 110 is not particularly limited, and is, for example, preferably 10 to 33mm, more preferably 12 to 28 mm. When the value is equal to or higher than the lower limit, the product of surface P1P of implanted hair bundle 114 can be sufficiently secured, and when the value is equal to or lower than the upper limit, the oral cavity operability can be further improved.

The thickness of the head 110 may be determined in consideration of the material, and is preferably 2.0 to 4.0mm, for example. If the lower limit value is not less than the lower limit value, the strength of the head 110 can be further improved, and if the upper limit value is not more than the upper limit value, the accessibility to the molar teeth can be improved, and the intraoral operability can be further improved.

In order to allow the neck 120 to contact the lips when the head 110 is inserted into the oral cavity, the length of the neck 120 is preferably, for example, 25 to 70 mm.

The width of the neck 120 is formed as: the distance from the minimum value is constant or gradually increases toward the rear end. When the width of the neck portion 120 is constant from the position of the minimum value toward the rear end side, the position of the minimum value is defined as the position of the most front end side. The neck 120 in the present embodiment is formed as follows: the width thereof gradually increases from the position 121 of the minimum value toward the rear end side. The width of the neck 120 may be determined in consideration of the material, and for example, the minimum width of the neck 120 is preferably 3.5mm or more and 4.5mm or less, and more preferably 3.7mm or more and 4.3mm or less. If the lower limit value is not less than the lower limit value, the strength of the neck 120 can be further improved, and if the upper limit value is not more than the upper limit value, the lips are easily closed, and the accessibility to the molar teeth can be improved, and the intraoral operability can be further improved.

Further, let W be a width at a position 122 shifted from a position 121 where the width of the neck portion 120 is the minimum toward the rear end side by 10mm in parallel with the hair-planted surface 111₁mm and a thickness D in a direction perpendicular to the flocked surface 111 at the position 122₁mm time, from D₁/W₁The value obtained is preferably 0.7 or more and 2.5 or less, more preferably 0.8 or more and 2.0 or less, and particularly preferably 0.8 or more and 1.5 or less.

The minimum width of the neck 120 is 3.5mm to 4.5mm, and is defined by D₁/W₁If the obtained value is less than the lower limit value, the neck 120 may be easily bent during brushing and operability may be degraded, and if the neck 120 is widened and operability is impaired, the thickness of the head 110 may not be conspicuous in appearance, and the impression of the product may be impaired.

On the other hand, from D₁/W₁When the obtained value exceeds the upper limit, the thickness D is present₁The larger size, the possibility that the lips are difficult to close when brushing the occlusal surface. Further, the effect of improving the operability by thinning the head portion 110 may be impaired. Thus, from D₁/W₁When the value obtained is 0.7 or more and 2.5 or less, one is easyThe brush is performed by closing the lips while maintaining the improved operability obtained by thinning the head 110.

It is also known that, in general, the amount of deflection of a rigid body is greatly affected by the "second moment of area" when the material is the same. Since the amount of deflection is proportional to the 1 st power of the width W and the 3 rd power of the thickness D, it is preferable to minimize the width while maintaining the thickness D in order to reduce the amount of deflection.

For example, let us say the flexural modulus M (mm)⁴)＝W×D³By the width W at the location 121 of the neck 120₀Thickness D₀Calculated deflection coefficient M₀Preferably 165mm⁴Above, 625mm⁴Hereinafter, more preferably 180mm⁴Above, 525mm⁴Hereinafter, 200mm is particularly preferable⁴Above, 330mm⁴The following. Further, by the width W at location 122 of the neck 120₁Thickness D₁Calculated deflection coefficient M₁Is 165mm⁴Above, 625mm⁴Hereinafter, more preferably 180mm⁴Above, 525mm⁴Hereinafter, more preferably 200mm⁴Above, 330mm⁴Below, more preferably 270mm⁴Above, 310mm⁴The following. From a position 121, at a position deviated by 20mm from the hair-planted surface 111 toward the rear end side in parallel with the neck 120, the width W₂Thickness D₂Calculated deflection coefficient M₂Preferably 350mm⁴Above 550mm⁴The following. A width W in the neck portion 120 at a position deviated from a position 121 by 30mm from the hair-planting surface 111 toward the rear end side in parallel₃Thickness D₃Calculated deflection coefficient M₃Preferably 600mm⁴Above 1500mm⁴The following.

Flexural modulus M at position 122 if at 165mm⁴Above, 625mm⁴In the following, it is possible to contribute to improvement of the brushing property at the time of closing the lips and to prevent deterioration of the operability due to excessive deflection.

The rate of change of the deflection coefficient M is preferably 1.0 or more and 1.3 or less between the position 121 and the position 122. Also, as at position 122 and slaveThe rate of change of the deflection coefficient M between positions 20mm away from the position 121 toward the rear end side is preferably 1.3 to 1.8. The rate of change of the deflection coefficient M between a position 20mm away from the position 121 toward the rear end side and a position 30mm away from the position 121 toward the rear end side is preferably 1.7 or more and 3.0 or less, and more preferably 1.8 or more and 3.0 or less. The change rate is a value obtained by dividing the deflection coefficient at the position on the rear end side by the deflection coefficient at the position on the front end side, and is based on the deflection coefficient M at the position 121, for example, between the position 121 and the position 122₀And the coefficient of deflection M at location 122₁As M₁/M₀The calculated value.

When the deflection coefficient M and the rate of change thereof are within the above ranges, the operability is not deteriorated, and brushing is easily performed when the lips are closed.

Tuft 114 has a plurality of bristles. The length (hair length) from the hair-planted surface 111 to the tip of the hair bundle 114 is determined in consideration of the stiffness of the bristles required for the hair bundle 114, and may be, for example, 6 to 13 mm. All tufts 114 may be of the same tuft length or may be different from one another.

The thickness (tuft diameter) of the tufts 114 can be determined in consideration of the stiffness of the bristles required for the tufts 114, and can be, for example, 1 to 3 mm. All of tufts 114 may be of the same tuft diameter or may be different from one another.

Examples of the bristles constituting the bundle 114 include bristles having a diameter gradually decreasing toward the distal end of the bristle, bristles having a sharpened distal end (tapered bristles), bristles having a substantially uniform diameter from the bristle surface 111 toward the distal end of the bristle (straight bristles), and the like. The straight bristles may have a flat bristle tip substantially parallel to the bristle-implanting surface 111, or may have a hemispherical bristle tip.

Examples of the material of the brush include polyamides such as 6-12 nylon (6-12NY) and 6-10 nylon (6-10NY), polyesters such as PET, PBT, polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN) and polybutylene naphthalate (PBN), polyolefins such as PP, polyolefin elastomers such as polyolefin elastomers and styrene elastomers. These resin materials may be used 1 kind alone or in combination of 2 or more kinds. Further, as the bristles, there may be mentioned bristles made of polyester having a multi-core structure including a core portion and at least 1 or more layers of sheath portions provided outside the core portion.

The cross-sectional shape of the brush is not particularly limited, and may be circular such as a perfect circle and an ellipse, polygonal, star-shaped, three-leaf clover-shaped, four-leaf clover-shaped, or the like. The cross-sectional shapes of all the bristles may be the same or different.

The thickness of the brush is determined by considering the material, and when the cross section is circular, it may be 6 to 9 mils (1 mil: 1/1000 inch: 0.025mm), for example. Further, a plurality of bristles having different thicknesses may be arbitrarily combined for use in consideration of the feeling of use, the feeling of brushing, the cleaning effect, the durability, and the like.

The toothbrush 11 is manufactured by first molding the handle body 12 by injection molding.

Then, the tufts 114 are implanted in the resulting head 110 of the handle body 12. Examples of the method for implanting the hair bundle 114 include: a flat wire type hair-planting in which a bundle of hairs 114 is implanted by folding the bundle of hairs 114 in two and driving a flat wire sandwiched therebetween into a planting hole 112; a thermal fusion bonding method in which the lower end of the bundle of bristles 114 is pressed into a molten resin serving as a bristle-implanted portion and fixed; and an in-mold process (in-mold process) for molding the implanted portion by heating the lower end of the bundle 114 to form a molten mass and then injecting a molten resin into a mold.

As described above, according to the toothbrush 11 of the present embodiment, while the minimum width of the neck 120 is set to 3.5mm or more and 4.5mm or less, the state in which the lips are easily closed and the brushing is easily performed is ensured, and the value obtained from D/W is set to 0.7 or more and 2.5 or less, so that it is possible to avoid the deterioration of the operability even when a general-purpose resin such as polypropylene is used.

In the case of flat wire flocking, a pressure is applied by driving a flat wire into the head 110. On the one hand, if the head 110 is thin and has low strength against deformation when a force is applied, and on the other hand, if the neck 120 is thick and has high strength, pressure during brushing concentrates on the head 110, and the head 110 may be bent more and the usability may be degraded. In contrast, according to the toothbrush 11 of the present embodiment, since the neck portion 120 is made thin and has a certain degree of flexibility, the pressure during brushing can be dispersed from the head portion 110 to the entire neck portion 120, and usability can be improved. Therefore, in the case of the flat-wire type hair planting, the effects of the present invention can be obtained particularly remarkably.

(deflection of head A)

The deflection a of the head is measured by the following method (α).

Method (a):

the bristle-implanted surface of the head is directed upward in the vertical direction, and the height of the tip of the handle body in a state where the position of the boundary P1 between the head and the neck of the toothbrush is fixed is set as a reference height. Further, in a state where the position of the boundary P1 was fixed, a 200g hammer was suspended at a position 10 ± 3% away from the distal end of the implanted portion with respect to the length of the implanted portion in the long axis direction of the head, and the amount of displacement (in mm) in height from the reference height of the distal end of the handle body after 10 seconds was used as the deflection amount a of the head.

The "length of the implanted portion in the longitudinal direction" means a distance between the distal end of the implanted hole located on the most distal side and the rear end of the implanted hole located on the most distal side when the head is viewed in a plan view.

In a toothbrush having a head portion with a shape narrowing in the width direction from the neck portion, the boundary P1 is: the end points of the curves of the head forming both edges of the chamfer from the neck in plan view, that is, the positions where the bending directions of the curves forming the chamfer change. The plan view is a view of the toothbrush from the bristle-implanted side of the head.

This will be described in more detail with reference to the toothbrush 21 shown in fig. 5A, 5B, 6A and 6B. The toothbrush 21 includes: a head portion 22 that is approximately quadrangular in plan view, a neck portion 24 provided to extend to the head portion 22, and a grip portion 26 provided to extend to the neck portion 24. The head 22 is provided with a bristle-implanted portion (not shown). Hereinafter, the head 22, the neck 24, and the grip 26 are collectively referred to as a grip body 210.

The head portion 22, in plan view, expands in width as it goes from the front end 29 toward the neck portion 24, then extends with an equal width, and then narrows in width until its boundary P1 with the neck portion 24. The neck portion 24 extends from the boundary P1 toward the grip portion 26 with substantially the same diameter, and then expands in diameter until it reaches the boundary P2 of the grip portion 26.

Boundary P1 in toothbrush 21 is: the end points of the curves forming the both edges of the chamfer from the neck portion 24, that is, the positions where the bending directions of the curves forming the chamfer are changed in the plan view shape of the head portion 22. In fig. 5A, the boundary P1 of the head and neck is: the curve R1 narrowing in width from both edges forming the corner cut of the head portion 22 in plan view changes to the position of a straight line forming both edges of the same width. Further, in the case of a toothbrush in which the neck portion is widened in width toward the handle portion in a plan view, the boundary P1 coincides with a position in which the width in the head portion and the neck portion is smallest in a plan view.

However, the position of the boundary P1 may be difficult to determine, for example, in a toothbrush in which the head and the neck are formed to have the same width. At this time, a position 17.5% away from the front end 29 of the handle body 210 with respect to the length L21 (for example, a position 31.5mm away from the front end 29 of the handle body 210 when the length L21 is 180 mm) is defined as the boundary P1.

For example, in the case where the width of the portion of the neck portion from the head is the same in plan view, the width is measured while gradually changing the position toward the head in the portion of the neck portion from the head, and the position at which the portion having the same width and the portion whose width starts to increase is changed is defined as the boundary P1. In addition, when the width of the portion of the neck portion from the head portion becomes narrower as it approaches the head portion in a plan view, the width is measured while gradually changing the position toward the head portion in the portion of the neck portion from the head portion, and the position at which the width is the smallest is defined as the boundary P1.

The deflection a of the head 22 is measured by the following method.

As shown in fig. 6A, the position of the narrowest part of the neck (boundary P1) is set so that the bristle surface 220 faces upward in the vertical directionThe toothbrush 21 is fixed by the fixture 2100. At this time, the height H is set to the height of the front end 29 of the handle body 210 as a reference height H₀。

Then, as shown in FIG. 6B, a weight 2102 of 200g was suspended at the position S, and the height of the tip 29 of the handle body 210 after 10 seconds was measured and taken as H₁. The S is: the head 22 is located 10 ± 3% away from the tip of the implanted part with respect to the longitudinal length L24 (fig. 5A) of the implanted part. For example, when the implanted portion is 19mm, S is a position 2.0mm away from the tip of the implanted portion.

Next, H is reacted with₁And H₀The absolute value of the difference is determined as a (unit is mm). The a may be measured by an altimeter or the like, for example. The assay was performed at 25. + -. 3 ℃ at room temperature.

The measurement was performed 5 times, and the average value of the displacement amounts a was defined as the deflection amount a of the head 22.

The deflection A is preferably 0.4 to 3.0, more preferably 0.4 to 2.5, and still more preferably 0.4 to 2.0. The deflection A is preferably 0.5 to 3.0, more preferably 0.5 to 2.5, and still more preferably 0.5 to 2.0. When the deflection amount a is within the above range, the head 22 itself is appropriately deflected, the implanted part implanted in the head 22 is soft, and the feeling of contact with the gum, i.e., the feeling of use, is further improved. When the deflection amount a is equal to or greater than the lower limit, the feeling of use is good. If the deflection amount a is equal to or less than the upper limit value, sufficient strength can be easily secured in the head 22. Further, toothbrush 21 is not too weak, and good oral cavity operability and cleaning force are easily obtained.

The amount of deflection a can be adjusted by adjusting the flexural modulus of the material of the head (i.e., the material of the handle body), the thickness, width, and the like of the head.

(deflection amount of neck B)

The neck deflection B is measured by the following method (β).

Method (β):

the bristle-implanted surface of the head is directed upward in the vertical direction, and the height of the distal end of the handle body in a state where the position P2 of the boundary between the neck and the handle of the toothbrush is fixed is set as a reference height. In the fixed state, a 200g hammer was suspended at a position 50 ± 3% away from the tip of the implanted part with respect to the length of the implanted part in the longitudinal direction of the head part, and the amount of displacement (in mm) in height from the reference height of the tip of the grip body after 10 seconds was used as the amount of deflection B of the neck part.

The boundary P2 between the neck and the grip is: the end point of the diameter expansion of the neck portion, that is, the end point of a straight line forming both edges of the widened portion or the position where the direction of bending of a curve forming both edges of the widened portion changes in plan view. In fig. 5A, it is: starting from a straight line or a curved line R2 forming both edges of the portion with a widened width in a plan view of the neck portion and the grip portion, there is changed a position of a curved line with a gradually narrowed width.

However, the position of the boundary P2 may be difficult to determine, for example, in a toothbrush in which the neck and the grip portion are formed to have the same width. At this time, a position apart from the front end 29 of the handle body 210 by 42.2% with respect to the length L21 (for example, a position apart from the front end 29 of the handle body 210 by 76.0mm when the length L21 is 180 mm) is defined as the boundary P2.

The deflection B of the neck 24 of the toothbrush 21 is measured in the same manner as the deflection a of the head, except that the position at which the toothbrush 21 is fixed by the jig 2100 and the position S of the suspending weight 2102 are different from the method of measuring the deflection a of the head 22.

In the measurement of the deflection B of the neck 24, the position where the toothbrush 21 is fixed by the jig 2100 is the boundary P2. Further, S is: the distance between the tip of the implanted part and the longitudinal length of the implanted part is 50 + -3%. For example, when the implanted portion is 19mm, S is a position 9.5mm apart from the tip.

Then, the reference height H before the suspension weight 2102 is obtained in the same manner as the method of measuring the deflection a of the head₀And the height H of the suspension weight 2102 after 10 seconds₁Absolute value of the difference (in mm). The assay was performed at 25. + -. 3 ℃ at room temperature. This measurement was performed 5 times, and the average value thereof was defined as the deflection amount B of the neck portion 24.

The deflection 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 deflection amount B is within the above range, the neck portion is deflected appropriately, and an appropriate cushioning property is exhibited, so that the contact feeling of the implanted portion with respect to the gum becomes better. If the deflection B is not less than the lower limit, the bristles can reach the corners of the oral cavity such as deep into the molars, thereby further improving the cleaning power in the oral cavity. Further, the penetration of the brush into the periodontal pocket is improved, and the cleaning power of the periodontal pocket is further improved. If the deflection B is less than the upper limit, the strength of the neck portion is easily suppressed from decreasing. Further, toothbrush 21 does not become too weak, and a good feeling of use is easily obtained.

The amount of deflection B can be adjusted by adjusting the flexural modulus of the material of the neck portion (i.e., the material of the handle body), the minimum diameter of the neck portion, the cross-sectional shape of the boundary P2, and the like.

The product (A x B) of the deflection A of the head and the deflection B of the neck is 0.8 to 10, preferably 1 to 10, more preferably 1 to 6, and still more preferably 1 to 3.5. Further, (A × B) is preferably 2 to 10. (A × B) within the above range, a moderate degree of cooperative flexing of the head 22 and the neck 24 can be obtained. Thus, when the implanted part is slid with respect to the part to be cleaned (tooth, gum, etc.), the implanted part exhibits softness and cushioning properties, and the contact feeling of the implanted part becomes good. The lower limit of (a × B) is 0.8 or more, preferably 1 or more. Further, 2 or more is preferable. When (a × B) is not less than the lower limit, appropriate deflection is obtained, and a good contact feeling with the gum is obtained, and a high massaging effect with respect to the gum is obtained, thereby improving a feeling of use. The upper limit of (a × B) is 10 or less, preferably 6 or less, and more preferably 3.5 or less. By setting (a × B) to the upper limit value or less, the region formed by the head portion 22 and the neck portion 24 is not excessively bent, and a decrease in operability and a decrease in cleaning force can be suppressed. Further, it is possible to suppress a decrease in the massaging effect on the gums due to the excessive deflection and a feeling of weakness when the user uses the toothbrush 21. Further, the strength of the toothbrush 21 is improved, and the durability is improved.

Deflection A and deflection B, preferably A < B. When A < B, the operability of toothbrush 21 is further improved.

The difference (B-A) between the deflection A and the deflection B is preferably 1 or more, preferably 1.5 or more, and more preferably 2 or more. When the value is equal to or higher than the lower limit value, (B-a) the amount of deflection of the neck portion 24 is kept large with respect to the head portion 22, so that the cushioning property is improved, the contact feeling with the gum is improved, and the user can easily feel the massage effect on the gum.

Further, (B-A) is preferably 4 or less, more preferably 3 or less. When the value of (B-a) is less than the upper limit value, the amount of deflection of the neck portion 24 relative to the head portion 22 does not become excessively large, and the oral cavity operability is easily improved. Further, the user can easily feel soft when using the toothbrush 21.

The amount of (B-A) is preferably 1 to 4, more preferably 1 to 3.

The ratio (B/A) of the deflection B to the deflection A is preferably 1.5 to 5.0, more preferably 1.8 to 4.8.

The handle portion 26 is held while the toothbrush 21 is used. The grip of the grip 26 is not particularly limited, and may be a grip type or a pen grip type. In any of the holding methods, the handle portion 26 is held by bringing a thumb or the like into contact with the vicinity of the neck rear end boundary P2, because cleaning is usually performed while applying pressure to the target portion.

Then, the head 22 is inserted into the oral cavity, and the bristle planting portion is slid on the cleaning target portion while pressing the grip portion 26. The force applied to the grip portion 26 is transmitted to the head portion 22 through the neck portion 24, and further transmitted from the head portion 22 to the flocked portion, whereby the flocked portion cleans the cleaning target portion while applying pressure thereto. In this case, when the product (A x B) of the deflection A of the head and the deflection B of the neck is 0.8 to 10, a moderate deflection in cooperation between the head and the neck can be obtained. As a result, the bristles implanted into the head 22 of the toothbrush 21 can easily reach the corner corners in the oral cavity such as the deep side of the molar teeth, and the oral cavity cleaning power is improved. Further, the bristles are easily inserted into the periodontal pocket, and the cleaning power of the periodontal pocket is improved. Further, since appropriate deflection can be obtained, the softness and cushioning property of the implanted part are improved, the contact feeling of the implanted part to the gum becomes good, a good massage effect to the gum can be obtained, and the feeling of use is improved.

[ examples ]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples, and can be modified and implemented as appropriate within a range not departing from the gist thereof.

[ Table 1]

(examples 1 to 5, comparative examples 1 to 7)

Toothbrushes of examples 1 to 5 and comparative examples 1 to 7, in which a neck portion 120 was formed, were manufactured in accordance with the specifications shown in [ table 1 ]. The head part and the handle part have the same width, length, thickness and shape. The PP resin was injection-molded to obtain an integrally molded article of the head and the grip body as shown in FIGS. 3 to 4 (from the tip of the head toward the grip body, the arrangement of the graft pores was 3 rows by 1, 4 rows by 6, and 3 rows by 1. the head had a width of 10mm, a length of 25mm, a thickness of 3.0mm, the grip body had a length of 110mm, and the neck had a length of 48 mm). A bundle of tapered bristles (7.5mil) formed of filaments made of PBT was implanted into the head through a flat-wire type bristle planting to manufacture a toothbrush.

In each example, the value obtained from D/W at the position where the width of the neck part is the smallest, the values obtained from D/W at positions deviated from the smallest position by 10mm, 20mm, and 30mm toward the rear end side, and W × D³The obtained values are shown in Table 2]As shown. In addition, the number of the groups is W × D in each example³The calculated rate of change of the obtained value in the deflection coefficient at each position as described above is shown in Table 3]As shown.

(evaluation method)

For the toothbrushes of the respective examples, "the oral cavity operability (ease of movement in the mouth) of the toothbrush" was evaluated by the following method.

< operability of toothbrush >

For the operability of the toothbrush, the "oral operability" was evaluated by the following evaluation criteria using the toothbrushes of each example by the professional experimental group 10. The average score of 10 persons in the professional test group 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 ease of movement in the mouth is very felt.

And 2, dividing: the ease of movement in the mouth is felt.

1 minute: the ease of movement in the mouth is not so much felt.

0 minute: ease of movement in the mouth is not felt.

[ Table 2]

[ Table 3]

Width x thickness³[W×D³]Rate of change of

As shown in table 2, it was confirmed that: the thickness of the head part is 2.0-4.0 mm, the minimum value of the width of the neck part is 3.5-4.5 mm, the value obtained by D/W at the position deviated from the position of the minimum value in the neck part to the rear end side is 0.7-2.5, and the deflection coefficient M (mm⁴)＝W×D³Is 165mm⁴Above, 625mm⁴In the following case, good operability can be obtained.

While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it is needless to say that the present invention is not 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 without departing from the scope of the present invention.

For example, in the toothbrush 11 of the above embodiment, the configuration in which the width of the neck portion 120 gradually increases from the minimum width position toward the rear end side is exemplified, but the configuration is not limited thereto, and a configuration in which the same width extends toward the rear end side may be employed. Even in the configuration in which the neck portion 120 extends toward the rear end side with the same width, the value obtained by D/W at a position deviated by 10mm from the minimum width position toward the rear end side is preferably 0.7 or more and 2.5 or less.

Claims

1. A toothbrush is characterized in that a toothbrush head is provided,

the disclosed device is provided with: a head portion disposed on a front end side and having a hair bundle implanted therein by flat line hair-planting on a hair-planting surface, a neck portion provided to extend to a rear end side of the head portion, and a grip portion provided to extend to a rear end side of the neck portion;

the thickness of the head part is 2.0-4.0 mm,

the minimum width of the neck part is 3.5-4.5 mm,

the neck portion is formed as: the width is constant or gradually increased from a position where the width in a direction parallel to the bristle surface and perpendicular to the longitudinal direction of the grip portion is a minimum toward the rear end side,

the width of the neck part is W mm, the thickness of the neck part in the direction perpendicular to the flocking surface is D mm, and the flexural coefficient is M (mm)⁴)＝W×D³When the temperature of the water is higher than the set temperature,

starting from the position where the width of the neck portion is the minimum value,

a deflection coefficient M at a position deviated by 10mm from the rear end side in parallel with the hair-planted surface₁(mm⁴)＝W×D³Is 165mm⁴Above, 310mm⁴In the following, the following description is given,

the width W of the position deviated 10mm from the starting point to the rear end side in parallel with the hair-planted surface₁mm, thickness in the direction perpendicular to the flocked surface is D₁mm time, from D₁/W₁The obtained value is 0.7 to 2.5 inclusive,

of the deflection amount a of the head measured by the following method a and the deflection amount B of the neck measured by the following method B,

the difference between the deflection A and the deflection B, namely B-A, is 1 to 4mm,

the deflection A is 0.4 to 3.0mm,

method α: the bristle face of the head is directed upward in the vertical direction, the height of the tip of the handle body in a state in which the position of the boundary P1 between the head and the neck of the toothbrush is fixed is set as a reference height, a hammer of 200g is suspended at a position 10 + -3% away from the tip of the bristle part with respect to the length in the longitudinal direction of the bristle part in the head in a state in which the position of the boundary P1 is fixed, and the amount of displacement in the height of the tip of the handle body from the reference height after 10 seconds is set as the deflection A of the head in mm,

method beta: the bristle-implanted surface of the head is directed upward in the vertical direction, the height of the tip of the handle body in a state in which the position of the boundary P2 between the neck and the handle of the toothbrush is fixed is set as a reference height, a hammer of 200g is suspended at a position 50 + -3% away from the tip of the bristle-implanted portion with respect to the length in the longitudinal direction of the bristle-implanted portion in the head in the fixed state, and the amount of displacement in height from the reference height of the tip of the handle body after 10 seconds is set as the deflection amount B of the neck.

2. Toothbrush according to claim 1, characterised by a flexural coefficient M at the location of the starting point₀A deflection coefficient M at a position deviated from the starting point by 10mm toward the rear end side₁Rate of change of (i.e. M)₁÷M₀Is 1.0 to 1.3 inclusive.

3. The toothbrush according to claim 1 or 2, characterized in that the flexural coefficient M at a position deviated from the position of the starting point toward the rear end side by 20mm₂A deflection coefficient M at a position deviated from the starting point by 30mm toward the rear end side₃Rate of change of (i.e. M)₃÷M₂Is 1.7 to 3.0 inclusive.

4. Toothbrush according to claim 1 or 2, characterised by a flexural coefficient M at the origin₀(mm⁴)＝W×D³Is 165mm⁴Above, 330mm⁴The following.

5. The toothbrush of claim 3, wherein the coefficient of deflection M₃Is 600mm⁴Above 1500mm⁴The following.

6. The toothbrush according to claim 1, wherein the difference between the deflection A and the deflection B, B-A, is 1.5 to 4 mm.

7. The toothbrush of claim 1, wherein the deflection A is 0.4-2.5 mm.

8. The toothbrush of claim 1, wherein D is₁/W₁The obtained value is 0.8 to 1.5.

9. The toothbrush according to claim 1, wherein the flexural coefficient M is set at a position deviated from the position of the starting point toward the rear end side by 10mm₁A deflection coefficient M at a position deviated from the starting point by 20mm toward the rear end side₂Rate of change of (i.e. M)₂÷M₁Is 1.3 to 1.8 inclusive.

10. A toothbrush according to claim 1 or claim 2, wherein the neck has a length of from 25 to 70 mm.

11. The toothbrush of claim 1 or 2, wherein the head has a length of 10 to 33 mm.

12. The toothbrush according to claim 1 or 2, wherein the handle body formed by joining the head, the neck and the handle is made of a resin having a flexural modulus of elasticity of 1000MPa to 2200MPa as measured according to JIS 7171.

13. The toothbrush according to claim 1 or 2, wherein the resin of the handle body formed by joining the head, the neck and the handle is a polypropylene resin, a polyacetal resin, a polystyrene resin, a polyethylene terephthalate resin, a polybutylene terephthalate resin, an acrylonitrile butadiene styrene resin, a polyarylate resin, a polycarbonate resin, an acrylonitrile styrene resin.

14. The toothbrush of claim 13, wherein the resin of the handle body is a polypropylene resin.