JP2015231500A - toothbrush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toothbrush in which supporting position of the toothbrush may be easily positioned at a rear side in a grip main body part, fatigue is hardly provided in use, excessive brushing pressure can be reduced unconsciously.SOLUTION: A toothbrush 1 of the present invention has a total weight of 5 g or more and 30 g or less, and a full length (L1) of more than 160 mm and 200 mm or less. In the toothbrush 1, when i) an explanatory variable C is a ratio ((L2×100)/L1) of a straight line distance (L2) from a rear end part 3e of the grip main body part 3 to a gravity center G of the toothbrush relative to a full length (L1); ii) an explanatory variable T is a periphery length (S1) at a position P1 apart forward from the rear end part 3e by 90 mm; and iii) an explanatory variable R is a ratio (S1/S2) of the periphery length (S1) at the position P1 relative to the periphery length (S2) at a position P2 apart forward from the rear end part 3e by 20 mm, a handle configuration variable P in the following formula (1) is 150 or more and 350 or less. P=4.57+5.91C+0.515T+154R...(1)

Description

  The present invention relates to a toothbrush including a brush portion in which a hair bundle is implanted and a handle main body portion continuous with the brush portion.

  When brushing with a toothbrush, if the brushing pressure is too high, the tooth surface may be shaved or the gums may be damaged. If the tooth surface is shaved, the possibility of becoming a decayed tooth increases. In addition, when the gums are injured and the gums fall and the roots of the teeth are exposed, for example, a “hypersensitivity” symptom of cold things may appear.

  For example, in Patent Document 1, as a technique for softening the feeling of gingiva during brushing, two portions, a portion gripped by the thumb and forefinger, and a portion gripped by the little finger and the palm of the little finger are made flat. An improved toothbrush is described.

  Patent Document 2 describes a toothbrush in which each dimension of the upper part of the gripping part and the lower part of the gripping part is improved within a predetermined range as a technique for effectively removing dental plaque that is easy to hold during brushing, is not easily fatigued. In addition, Patent Document 3 describes a toothbrush that is easy to hold, has excellent operability, and that effectively removes plaque, and that has an elastic modulus on the rear end side of the gripping portion that is equal to or higher than the elastic modulus on the front end side. Yes.

JP 2008-5967 A JP 2002-85157 A JP 2003-135148 A

  However, since the toothbrush of patent document 1 is a form which induces supporting a toothbrush in the center part of a toothbrush so that it may show also in the usage example of FIG. 8, it is a brushing pressure with respect to the user with a high brushing pressure. There is a problem in reducing this.

  The toothbrush described in Patent Document 2 is also intended to grip the upper part of the gripping part, which is in the vicinity of the head part of the toothbrush handle, and does not move the position supporting the toothbrush to the rear side of the handle body part. . Therefore, there is a problem in reducing the brushing pressure for a user having a high brushing pressure.

  Moreover, since the toothbrush of patent document 3 has specified the elasticity modulus of the front end side and the rear end side on the boundary of the center part of a handle | pattern, the position which supports a toothbrush intends the center side of a handle | pattern. It is not expected to move the position supporting the toothbrush to the rear end side of the handle body. Therefore, in the toothbrush disclosed in Patent Document 3, there is still a problem in reducing the brushing pressure for a user having a high brushing pressure.

  Therefore, this invention relates to the toothbrush which can eliminate the fault which the prior art mentioned above has.

This invention is a toothbrush provided with the brush part by which the hair | bristle bundle was flocked, and the handle | body main-body part which continues to this brush part, Comprising: The total weight of the said toothbrush is 5-30 g, The full length (L1) of the said toothbrush ) Is a linear distance greater than 160 mm and less than or equal to 200 mm, and i) from the rear end portion of the handle body portion opposite to the brush portion with respect to the total length (L1) to the center of gravity of the toothbrush The linear distance (L2) ratio ((L2 × 100) / L1) is an explanatory variable C, ii) the outer peripheral length (S1) at a position 90 mm away from the rear end portion of the handle body portion toward the brush portion. ) With the explanatory variable T, and iii) the outer peripheral length (S2) at the position 90 mm away from the outer peripheral length (S2) at the position 20 mm away from the rear end of the handle main body portion toward the brush part. Ratio) and (S1 / S2) performing a multiple regression analysis as explanatory variables R, derived handle shape variables of the formula (1) (objective variable P) is directed to a toothbrush is 150 to 350.
P = 4.57 + 5.91C + 0.515T + 154R (1)

  According to this invention, since the position which supports a toothbrush is easy to move to the back side in a handle | body main-body part, excess brushing pressure can be reduced unconsciously.

FIG. 1 is a perspective view showing a toothbrush according to an embodiment of the present invention. FIG. 2 is a plan view seen from the front side of the toothbrush shown in FIG. FIG. 3 is a side view of the toothbrush shown in FIG. 1 viewed from the side. 4 is a cross-sectional view taken along line IV-IV shown in FIG. 5 is a cross-sectional view taken along line VV shown in FIG. FIG. 6 is a diagram illustrating a toothbrush used for selecting subjects. FIG. 7 is a diagram illustrating a toothbrush of Comparative Example 5. FIG. 8 is a diagram illustrating a toothbrush of Comparative Example 6. FIG. 9 is a graph plotting the total weight on the vertical axis and the handle shape variable on the horizontal axis for the toothbrushes of Examples 1 to 3 and Comparative Examples 1 to 7.

Hereinafter, the present invention will be described based on preferred embodiments with reference to FIGS.
FIG. 1 is a diagram showing a toothbrush 1 (hereinafter also simply referred to as “toothbrush 1”) according to an embodiment of the present invention.
The toothbrush 1 includes a brush portion 2 in which a hair bundle 21 is planted, and a handle body portion 3 continuous with the brush portion 2. The toothbrush 1 is formed long in the axial direction (Y direction). Here, the width direction which is a direction perpendicular to the axial direction (Y direction) will be described as the X direction. Moreover, in this specification, in the axial direction (Y direction) of the toothbrush 1, the brush part 2 side will be described as the front side, and the end side of the handle opposite to the brush part 2 will be described as the rear side. Moreover, the surface side which has the hair | bristle bundle 22 in the brush part 2 of the toothbrush 1 is demonstrated as a front side, and the other side is demonstrated as a back side.

  The brush part 2 is formed by flocking the hair bundle 21 on the front side of the flocking table 22. Specifically, as shown in FIGS. 1 to 3, the brush unit 2 is provided with a plurality of tuft holes (not shown) on one side on the front side of the flocking table 22, and each tuft hole has a Tufts (hair bundles 21), which are bundles of bristle made of a synthetic resin such as polyethylene and nylon, are formed by being implanted and fixed by, for example, a method of driving a flat wire.

  As shown in FIGS. 1 to 3, the handle body 3 is continuous with the brush 2 and is formed longer from the brush 2 toward the rear side in the axial direction (Y direction). Here, the “pattern body 3” is mainly a portion held by the user and a portion gripped by the user when the toothbrush 1 is used. Preferably, the “pattern main body 3” does not include a character doll provided for the purpose of decoration other than the purpose of gripping or a decorative object such as a bell at the rear end 3e. Here, the above-mentioned decorative object has a region in which the outer peripheral length protrudes in the circumferential direction by 10% or more with a step from the brush portion 2 side to the rear end side in the vicinity of the rear end portion 3e, or The outer peripheral length is larger than 10% and protrudes in the circumferential direction, and has irregular irregularities formed on the outer peripheral surface. It is preferable that such a decorative object is not provided in the toothbrush of the present invention because it is difficult to grasp and easily disturbs when the position supporting the toothbrush is moved to the rear side of the handle body 3. Therefore, in order to adjust the position of the center of gravity, which will be described later, the outer peripheral length is shorter than the outer peripheral length of the handle main body 3 and has a region protruding to the rear end side of the handle main body 3, preferably the rear What has the area | region which protrudes in the end side with the length within 8 mm is considered as a part of the handle | body main-body part 3. FIG.

  As materials for the flocking table 22 and the handle body 3 of the brush part 2, polyacetal resin (POM), polypropylene resin (PP), polystyrene resin (PS), polyethylene terephthalate resin (PET), acrylonitrile butadiene styrene resin (ABS) , Cellulose propionate resin (CP), polyarylate resin, polycarbonate resin, acrylonitrile styrene resin (AS), polyester (PE), polytrimethylene terephthalate (PTT), polycyclohexanedimethylene terephthalate (PCTA), It can use individually or in mixture of 2 or more types.

  The total weight of the toothbrush 1 is 5 g or more and 30 g or less from the viewpoint of preventing easy fatigue during use and strength, and is preferably 5 g or more and 20 g or less from the viewpoint of further reducing fatigue. The total weight of the toothbrush 1 is not only the handle main body 3 of the toothbrush 1 but also the weight including the ball 31 for weight adjustment, the decorative part when there is a decoration, and the tuft that has been implanted.

  In addition, the toothbrush 1 has a total length (L1) (see FIG. 2) larger than 160 mm in a linear distance from the viewpoint of controlling the brushing pressure and from the viewpoint of usability such as easy application of the brush portion of the targeted tooth. It is 200 mm or less, preferably 170 mm or more and 190 mm or less.

As a result of intensive studies, the present inventors conducted multiple regression analysis based on the characteristic values of i) explanatory variable C, ii) explanatory variable T, and iii) explanatory variable R shown below. If the value of the handle shape variable (objective variable P) of the multiple regression equation (the following equation (1)) specified for the toothbrush is in the range of 150 to 350, the position where the toothbrush is supported is the handle body. It has been found that the toothbrush can easily move to the rear side of the part and can reduce excessive brushing pressure unconsciously.

P = 4.57 + 5.91C + 0.515T + 154R (1)

From the viewpoint of easily moving the position supporting the toothbrush backward, the value of the handle shape variable (object variable P) is 150 or more, preferably 180 or more, more preferably 220 or more, 350 or less. Preferably, it is 330 or less. The value of the toothbrush shape variable (objective variable P) is 150 or more and 350 or less, preferably 180 or more and 350 or less, and more preferably 220 or more and 330 or less.

  The multiple regression analysis is executed by software of a personal computer that performs various types of information processing. As such software, for example, spreadsheet software (Microsoft Excel manufactured by Microsoft, SPSS manufactured by SPSS, etc.) can be used.

  i) Regarding the explanatory variable C, the toothbrush 1 will be described as an example. As shown in FIG. 2, the explanatory variable C refers to the length of the toothbrush 1 from the rear end 3 e in the handle main body 3 with respect to the entire length (L1) of the toothbrush 1. This means the ratio ((L2 × 100) / L1) of the linear distance (L2) to the center of gravity G. In the toothbrush 1, as will be described later, a metal ball 31 is provided at the rear end 3 e, but the ball 31 has a shorter circumference than the circumference (outer circumference) of the handle body 3. Since it has the area | region which protrudes in the rear-end side of the pattern main-body part 3, it is considered as a part of the handle-body main part 3, and the rear-end part 3e at the time of measuring a linear distance (L2) Part included.

  The explanatory variable C is preferably 15% or more, more preferably 18% or more, from the viewpoint of moving the position where the toothbrush is supported to the rear side, and from the viewpoint of stabilization of operability when the supporting position is moved to the rear side. More preferably, it is 25% or more, preferably 45% or less, more preferably 42% or less, and further preferably 40% or less. The explanatory variable C is preferably 15% or more and 45% or less, more preferably 18% or more and 42% or less, and further preferably 25% or more and 40% or less.

  ii) The explanation variable T will be explained by taking the toothbrush 1 as an example. As shown in FIG. 2, the explanation variable T is 90 mm away from the rear end portion 3e of the handle body portion 3 to the brush portion 2 side (front side). Means the outer peripheral length (S1) at the position P1. As described above, in the toothbrush 1, the metal ball 31 is provided on the rear end 3 e, but the ball 31 has an outer peripheral length shorter than the outer peripheral length of the handle main body 3, and the handle main body 3 Since it has the area | region which protrudes in the rear-end side, it is considered as a part of the handle | body main-body part 3, and the rear-end part 3e at the time of pinpointing the position P1 90 mm away from the rear-end part 3e to the front side is used. The part of the ball 31 is included. Note that the position P1 of 90 mm means a position for guiding the placement of the thumb when the toothbrush 1 is gripped by a so-called palm grip and is gripped by the thumb and the index finger. Here, from the viewpoint of placing the thumb as described above, the outer peripheral length (S1) is an imaginary line connecting the tops of the convex portions when the outer peripheral surface of the handle main body portion 3 at the position P1 has irregularities. Let the length of (outermost circumference) be the outer circumference length (S1).

  The explanatory variable T is preferably 12 mm or more, more preferably 15 mm or more, and further preferably 17 mm or more from the viewpoint of the strength of the handle body 3, from the viewpoint of moving the position supporting the toothbrush to the rear side. , Preferably 35 mm or less, more preferably 30 mm or less. The explanatory variable T is preferably 12 mm or greater and 35 mm or less, more preferably 15 mm or greater and 30 mm or less, and even more preferably 17 mm or greater and 30 mm, from the viewpoint of the balance between the strength of the handle body 3 and the reduction of the brushing pressure. It is as follows.

  iii) Regarding the explanatory variable R, the toothbrush 1 will be described as an example. As shown in FIG. 2, the explanatory variable R is 20 mm away from the rear end portion 3e of the handle body portion 3 toward the brush portion 2 side (front side). The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 that is 90 mm away from the outer peripheral length (S2) at the position P2. As described above, in the toothbrush 1, the metal ball 31 is provided on the rear end 3 e, but the ball 31 has an outer peripheral length shorter than the outer peripheral length of the handle main body 3, and the handle main body 3 Since it has the area | region which protrudes in the rear-end side, it is considered as a part of the handle | body main-body part 3, and the rear-end part 3e at the time of pinpointing the position P2 20 mm away from the rear-end part 3e to the front side is used. The part of the ball 31 is included. The position P2 of 20 mm means the position of the little finger of the part gripped by the middle finger, the ring finger, the little finger, and the palm when the toothbrush 1 is gripped by a so-called palm grip. The outer peripheral length (S2) is the length (the outermost peripheral length) on the virtual outer peripheral surface connecting the tops of the convex portions when the outer peripheral surface of the handle main body portion 3 at the position P2 of 20 mm is uneven. means.

  The explanatory variable R is preferably 0.3 or more, more preferably 0.35 or more, and still more preferably 0 from the viewpoint of reducing the brushing pressure and the balance between the strength of the toothbrush and the ease of use of the toothbrush. From the viewpoint of moving the position supporting the toothbrush to the rear side, it is preferably 0.85 or less, more preferably 0.8 or less, and even more preferably 0.75 or less. Further, from the viewpoint of reducing the brushing pressure and the balance of the strength of the toothbrush, and from the viewpoint of ease of use of the toothbrush, it is preferably 0.3 or more and 0.85 or less, more preferably 0.35 or more and 0.8 or less. More preferably, it is 0.4 or more and 0.75 or less.

  In addition, the toothbrush 1 is preferably provided with a hollow or a cavity in the handle body 3 from the viewpoint of effectively reducing the brushing pressure while reducing the weight of the toothbrush, and in the vicinity of the rear end 3 of the handle body 3. Preferably, a member having a specific gravity greater than that of the handle main body 3, preferably a metal member, a member made of a metal and a resin, glass, as the inside or a part of the handle main body 3 at a position within 25 mm from the rear end 3 It is preferable to provide a member selected from a resin member and a glass member. Examples of the member made of metal and resin include a mixed molded product of metal and resin, a member coated with metal with resin, and a member coated with resin with metal. Examples of the member made of glass and resin include a member formed by mixing glass particles with resin. In addition, providing a member having a specific gravity larger than that of the handle body 3 as the inside or a part of the handle body 3 may be provided by integrally molding the member having a higher specific gravity, for example, by two-color molding. Another member may be fitted or loosely fitted.

  Specifically, for example, as shown in FIG. 1, a ball 31 made of metal such as stainless steel is preferably loosely fitted to the rear end 3 e of the handle main body 3. Furthermore, as shown in FIG. 4, the handle body 3 of the toothbrush 1 has a cavity formed inside from the rear end 3 to a position beyond the center of gravity G of the toothbrush 1 in the axial direction (Y direction). Is preferred. A more preferable form in this case will be described. A concave portion 32 for the ball 31 is formed at the rear end portion 3e of the handle body portion 3. The recessed portion 32 extends to the rear in the axial direction (Y direction) from the position of the center of gravity of the ball 31 and covers most of the ball 31. The ball 31 is not fixed inside the recessed portion 32 in the rear end portion 3e of the handle body portion 3, and is loosely fitted so as to be rotatable. Thus, since the ball 31 is loosely fitted to the rear end 3e of the handle body 3 in the toothbrush 1, there is an effect that the center of gravity of the toothbrush is greatly located on the rear side. In addition, the spherical diameter of the ball 31 is preferably 5 mm or more and 20 mm or less, and more preferably 6 mm or more and 10 mm or less.

  Further, the toothbrush 1 has a region T1 in which the cross-sectional area gradually increases from the position P1 90 mm away from the rear end 3e to the brush part 2 side (front side) in the handle body 3 toward the rear end 3e. It is preferable from the viewpoint of reducing the brushing pressure by moving the position for supporting the toothbrush to the rear side. For example, as shown in FIGS. 2 and 3, in the toothbrush 1, the axial direction from the position on the front side in the axial direction (Y direction) relative to the position P <b> 1 that is 90 mm away from the rear end portion 3 e in the handle body portion 3 toward the front side (Y direction) In the region T1 extending to the rear side beyond the center of gravity G of the toothbrush 1, the cross-sectional area in the width direction (X direction) (the cross-sectional area perpendicular to the axial direction) is the front in the axial direction (Y direction) It gradually increases from the side toward the rear side. As described above, the toothbrush 1 has a cavity inside the handle body 3, but the cross-sectional area does not exclude the cavity, and the handle body when viewed in cross-section in the width direction (X direction). The area surrounded by 3 outlines is taken as the cross-sectional area.

  In addition, as shown in FIGS. 2 and 3, the toothbrush 1 is arranged from the rear end portion 3 e of the handle body portion 3 to the brush portion 2 side (front side) from the viewpoint of reducing the brushing pressure of the user having a high brushing pressure. In the region T2 in the handle main body 3 from the position P1 90 mm away to the brush portion 2, the minimum outer circumference length (S3) in the region T2 with respect to the outer circumference length (S1) at the position P1 90 mm away. ) Ratio ((S3 × 100) / S1) is preferably 50% or more from the viewpoint of reducing the amount of resin while maintaining appropriate rigidity and moving the center of gravity of the toothbrush to the rear side, more preferably It is 60% or more, preferably 100% or less, more preferably 90% or less, and further preferably 80% or less. The ((S3 × 100) / S1) is preferably 50% or more and 100% or less, more preferably 60% or more and 90% or less, and further preferably 60% or more and 80% or less.

  Regarding the shape of the handle main body 3 of the toothbrush 1, a more preferable form will be described in detail. In a region extending from the rear end 3 e of the handle main body 3 to the vicinity of the position P 1 that is 90 mm away from the brush portion 2 side (front side), The contour of the handle body 3 when viewed in cross section in the width direction (X direction) is formed in a flat circular shape, preferably an ellipse or a capsule shape, which is long in the width direction (X direction). Since it is formed in this way, when the toothbrush 1 is gripped with a so-called palm grip, it is easy to grip with the thumb and index finger. In addition, the cross-sectional shape of the handle body 3 may be polygonal, and may have irregularities formed on the surface, or part thereof may be formed of an elastomer, and a flat shape having the major axis in the width direction. The shape is preferred.

The present invention is not limited to the above-described embodiment, and various modifications can be made.
For example, in the brush 1, a metal ball 31 is loosely fitted to the rear end 3 e of the handle body 3, but the ball 31 may be fixed, and a metal member having a shape other than a spherical shape may be used. It may be arranged. Moreover, metal members, such as such metal balls 31, may not be arranged. Further, the shape of the handle body 3 has a portion formed in a flat circular shape or the like, but it is not always necessary to have such a shape portion, and other shapes such as a square or a polygon You may have a part of various plane shape. In addition to the tufts (hair bundles 21), other auxiliary tufts and the like may be planted on the hair transplant table 22 of the brush unit 2.

  Hereinafter, the toothbrush of the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the scope of the present invention is not limited by the examples.

<Selection of subjects>
Using the toothbrush having the configuration shown in FIG. 6, three subjects who had gingival recession due to overbrushing were brushed by the following method. The characteristics of gingival recession due to overbrushing include thickened gingiva and overpolishing of the tooth surface, and in some cases, wedge-shaped defects. The average brushing pressure of 3 subjects was 432 gf. Moreover, regarding the toothbrush shown in FIG. 6, the total weight was 12.2g and the full length (L1) was 172.5 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is 46%, and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 90 mm away from the front is 30 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 0.88.

<Measurement of brushing pressure>
First, a strain gauge (product number “KFG-1-120-C1-11L3M2R” manufactured by Kyowa Dengyo Co., Ltd.) is pasted on the back of the handle body 40 to 50 mm behind the tip of the toothbrush, and calibration data at a load of 300 gf. Create Next, using the toothbrush, the paneler himself brushes for 10 seconds or more in the order of front teeth → right back teeth → left back teeth → front teeth. Here, the reason for brushing the front teeth twice is to cut off the first data. Then, data is recorded using a measuring instrument (part number “DBU-120A”, which is a bridge unit manufactured by Kyowa Dengyo Co., Ltd.) connected to a personal computer. The recorded data is analyzed using data analysis software installed in a personal computer, and an average brushing pressure is obtained. This data analysis software may create its own program, but may use a product number “DAS-200A” manufactured by Kyowa Dengyo Co., Ltd.

[Example 1]
A toothbrush having substantially the same configuration as the toothbrush shown in FIGS. In addition, the toothbrush of Example 1 is a structure which does not have a metal ball compared with the toothbrush shown in FIGS. Regarding the toothbrush of Example 1, the total weight was 10.9 g, and the total length (L1) was 180 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end of the handle body to the center of gravity G of the toothbrush with respect to the total length (L1) is 39%, and the rear end of the handle body The outer peripheral length (S1) at a position P1 that is 90 mm away from the front side is 19 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 that is 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 0.51. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 324.

[Example 2]
A toothbrush having the same configuration as the toothbrush shown in FIGS. The ball diameter of the ball provided in the toothbrush of Example 2 was 8 mm. Regarding the toothbrush of Example 2, the total weight was 13.0 g, and the total length (L1) was 182 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is (33%), and the rear end portion of the handle body portion The outer peripheral length (S1) at the position P1 90 mm away from the front side is 20 mm, and is 90 mm away from the outer peripheral length (S2) at the position P2 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 0.54. Therefore, the value of the handle shape variable (object variable P) obtained from the multiple regression equation (1) described above was 293.

[Example 3]
A toothbrush having the same configuration as the toothbrush shown in FIGS. The ball diameter of the ball provided in the toothbrush of Example 3 was 16 mm. Regarding the toothbrush of Example 3, the total weight was 28.1 g, and the total length (L1) was 187 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is 18%, and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 90 mm away from the front side is 21 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 0.37. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 179.

[Comparative Example 1]
A commercial product A (trade name “Clear Clean EX Habrush” manufactured by Kao Corporation) was used as the toothbrush of Comparative Example 1. Regarding the toothbrush of Comparative Example 1, the total weight was 10.3 g, and the total length (L1) was 182 mm. Further, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is 42%, and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 90 mm away from the front is 31 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 0.84. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 398.

[Comparative Example 2]
A commercial product B (trade name “Clear Clean Floss Plus Habrush” manufactured by Kao Corporation) was used as the toothbrush of Comparative Example 2. Regarding the toothbrush of Comparative Example 2, the total weight was 12.2 g, and the total length (L1) was 182 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is 43%, and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 that is 90 mm away from the front side is 38 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 that is 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 1.09. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 445.

[Comparative Example 3]
A commercial product C (trade name “Check Tapered Slim” manufactured by Kao Corporation) was used as the toothbrush of Comparative Example 3. Regarding the toothbrush of Comparative Example 3, the total weight was 10.2 g, and the total length (L1) was 182 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is 44%, and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 that is 90 mm away from the front side is 35 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 that is 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 1.25. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 475.

[Comparative Example 4]
A commercial product D (trade name “Clear Clean Whitening toothbrush” manufactured by Kao Corporation) was used as the toothbrush of Comparative Example 4. Regarding the toothbrush of Comparative Example 4, the total weight was 14.6 g, and the total length (L1) was 180 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is 43%, and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 that is 90 mm away from the front side is 35 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 that is 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 1.03. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 435.

[Comparative Example 5]
A commercially available product E (toothbrush having the configuration shown in FIG. 7) was used as a toothbrush of Comparative Example 5. Regarding the toothbrush of Comparative Example 5, the toothbrush shaft was provided with metal, the total weight of the toothbrush was 32.2 g, and the total length (L1) was 191 mm. In addition, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is (38%), and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 90 mm away from the front side is 43 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 1.00. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 405.

[Comparative Example 6]
A commercially available product F (toothbrush having the configuration shown in FIG. 8) was used as the toothbrush of Comparative Example 6. Regarding the toothbrush of Comparative Example 6, the total weight was 13.9 g, and the total length (L1) of the toothbrush was 161 mm. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is 43%, and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 that is 90 mm away from the front side is 28 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 that is 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 was 0.70. Therefore, the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above was 381.

[Comparative Example 7]
A toothbrush having the configuration shown in FIG. 1 of JP-A-2002-85157 was used as a toothbrush of Comparative Example 7. Regarding the toothbrush of Comparative Example 7, assuming that the length from the rear end of the brush part to the upper part of the gripping part is 40 mm, its total length (L1) is 173 mm, and assuming that the material of the handle is polypropylene, its total weight is 17 g. Become. Moreover, the ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion of the handle body portion to the center of gravity G of the toothbrush with respect to the total length (L1) is (40%), and the rear end portion of the handle body portion The outer peripheral length (S1) at a position P1 that is 90 mm away from the front side is 38 mm, and is 90 mm away from the outer peripheral length (S2) at a position P2 that is 20 mm away from the rear end of the handle main body forward. The ratio (S1 / S2) of the outer peripheral length (S1) at the position P1 is 0.90. Therefore, the value of the handle shape variable (object variable P) obtained from the multiple regression equation (1) described above is 400.

<Evaluation>
FIG. 9 shows a graph in which the total weight is plotted on the vertical axis and the handle shape variable (objective variable P) is plotted on the horizontal axis for the toothbrushes of Examples 1 to 3 and Comparative Examples 1 to 7. Moreover, the actual toothbrushing pressure was calculated | required by having the selected said test subject use the toothbrush of Examples 1-3 and Comparative Examples 1-4, and measuring the brushing pressure mentioned above. The obtained results are shown in Table 1.

  As is apparent from the results shown in Table 1, it can be seen that the value of the handle shape variable (objective variable P) obtained from the multiple regression equation (1) described above is substantially the same as the actual average brushing pressure value. . Further, as is apparent from the results shown in Table 1, when a subject whose brushing pressure exceeds 400 gf using the toothbrush having the configuration shown in FIG. It was found that the pressure value was reduced by 20% or more. On the other hand, even if the test subject used the toothbrushes of Comparative Examples 1 to 4, it was found that there was a toothbrush in which the actual average brushing pressure was hardly decreased and the average brushing pressure was improved. It was. From this, as shown in FIG. 9, the multiple regression equation (1) described above is in the range of 150 to 350 and the total weight is in the range of 5 g to 30 g. Compared to the toothbrushes of Comparative Examples 1 to 7, the position of supporting the toothbrush is easily located on the rear side of the handle main body, and is less likely to get tired during use, so that excessive brushing pressure can be reduced unconsciously. all right.

DESCRIPTION OF SYMBOLS 1 Toothbrush 2 Brush part 21 Hair bundle 22 Flocking table 3 Handle body part 3e Rear end part 31 Ball 32 Recess

Claims (6)

A toothbrush comprising a brush portion in which a hair bundle is implanted and a handle body portion continuous with the brush portion,
The total weight of the toothbrush is 5 g or more and 30 g or less,
The total length (L1) of the toothbrush is a linear distance greater than 160 mm and less than or equal to 200 mm,
i) The ratio ((L2 × 100) / L1) of the linear distance (L2) from the rear end portion located on the opposite side to the brush portion in the handle main body portion to the full length (L1) to the center of gravity of the toothbrush. Explanatory variable C,
ii) The outer peripheral length (S1) at a position 90 mm away from the rear end portion of the handle main body portion toward the brush portion side is an explanatory variable T,
iii) Ratio (S1 / S2) of the outer peripheral length (S1) at the position 90 mm away from the outer peripheral length (S2) at the position 20 mm away from the rear end portion of the handle main body portion toward the brush portion. As an explanatory variable R,
A toothbrush in which the handle shape variable (objective variable P) of the following formula (1) is 150 or more and 350 or less.

P = 4.57 + 5.91C + 0.515T + 154R (1)
  The toothbrush according to claim 1, wherein the explanatory variable R is not less than 0.3 and not more than 0.85.   The toothbrush according to claim 1, wherein the explanatory variable C is 15% or more and 45% or less.   The toothbrush according to any one of claims 1 to 3, wherein the explanatory variable T is 12 mm to 35 mm.   5. The method according to claim 1, further comprising a region in which the cross-sectional area gradually increases from a position 90 mm away from the rear end portion of the handle main body portion toward the brush portion toward the rear end portion. The toothbrush according to item. In the region of the handle main body part from the position 90 mm away to the brush part, the outer circumference length (S3) at the position within the area with respect to the outer circumference length (S1) at the position 90 mm apart. ) Ratio ((S3 × 100) / S1) is 50% or more and 100% or less, The toothbrush according to any one of claims 1 to 5.

Images