WO2011118538A1

WO2011118538A1 - Toothbrush

Info

Publication number: WO2011118538A1
Application number: PCT/JP2011/056644
Authority: WO
Inventors: 幸子中山; 良祐蜂須賀; 海之小林
Original assignee: ライオン株式会社
Priority date: 2010-03-24
Filing date: 2011-03-18
Publication date: 2011-09-29
Also published as: JP5530776B2; KR20130004299A; KR102031473B1; TWI520698B; CN102821648B; MY183865A; CN102821648A; TW201143675A; KR20170116245A; JP2011200296A

Abstract

A toothbrush configured so that a bristle bundle is less likely to come out of implanting holes, the toothbrush can be easily operated in the oral cavity, and having sufficient strength. A tooth brush is provided with a substantially flat plate-like head section (10) having an implanting surface (10a) in which a large member of implanting holes (11) are provided. Bristle bundles (1b) are each folded into two, and a flat line sandwiched between the two folded portions of the bristle bundle (1b) is driven into each of the implanting holes (11) to implant the bristle bundle (1b) into the implanting hole (11). The head section has a thickness in the range of 2.0-4.0 mm, and the minimum distance (W) between outermost implanting holes (11a) in the widthwise direction of the head section and a corresponding edge (12) of the head section is in the range of 0.4-0.9 mm.

Description

toothbrush

The present invention relates to an improvement in a toothbrush.
This application claims priority on March 24, 2010 based on Japanese Patent Application No. 2010-068132 filed in Japan, the contents of which are incorporated herein by reference.

Generally, a toothbrush is manufactured by fixing a bunch of brushes of nylon or polybutylene terephthalate (PBT) with a flat wire in a flock hole provided in the head part of the handle body in advance. Since the hair bundle planted using the flat wire is folded in half, it is difficult to come out from the flock hole. As a material of the head portion, polypropylene (PP) is widely used from the viewpoint of cost and formability.

By the way, in order to facilitate the brushing of every corner of the oral cavity, particularly the back teeth, with a toothbrush, it is better that the head part into which the hair bundle is implanted is thinner. For example, Patent Document 1 proposes a toothbrush having a handle body made of polyacetal resin and a thin head portion of 3 to 4 mm for the purpose of improving operability in the oral cavity.

Japanese Patent Laid-Open No. 7-143914

However, even the toothbrush described in Patent Document 1 may not have sufficient operability in the oral cavity, resulting in unpolished portions. Further, when the head portion is thinned, the bending strength of the head portion may be reduced. Further, along with the decrease in strength, appearance defects may occur due to the occurrence of cracks or whitening at the edge of the head portion.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a toothbrush in which a hair bundle is difficult to come out of a flock hole, is excellent in intraoral operability, and has sufficient strength.

The first aspect of the present invention comprises a substantially plate-like head portion provided with a plurality of flocked holes on the flocked surface, and the bristles of the brush are folded in half, and a flat wire sandwiched between them is formed in the flocked hole. A toothbrush in which the bristle bundle is implanted in the flocking hole by driving, wherein the head portion has a thickness of 2.0 to 4.0 mm, and the outermost portion in the width direction of the head portion. A toothbrush in which the shortest distance between the flocked hole and the edge is 0.4 to 0.9 mm.
According to a second aspect of the present invention, in the toothbrush according to the first aspect, the head portion is a toothbrush made of polybutylene terephthalate resin.

The toothbrush of the present invention has a bristle bundle that is difficult to come out of the flock hole, is excellent in intraoral operability, and has sufficient strength.

It is a side view which shows one Embodiment of the toothbrush of this invention. It is a top view which expands and shows the head part of the toothbrush shown in FIG.

An embodiment of the toothbrush of the present invention will be described.
1 and 2 show a toothbrush of the present embodiment. The toothbrush 1 of the present embodiment includes a handle body 1a including a head portion 10 and a bristle bundle 1b implanted in a flock hole 11 of the head portion 10.

The handle body 1 a includes a head portion 10, a grip portion 20 that is gripped during use, and a neck portion 30 that is disposed between the head portion 10 and the grip portion 20.
In the handle body 1a in the present embodiment, the head portion 10, the grip portion 20, and the neck portion 30 are made of the same resin.
Examples of the resin constituting the handle body 1a include polybutylene terephthalate resin (PBT), polypropylene resin (PP), polyacetal resin (POM), and resin in which a part of polycyclohexanedimethylene terephthalate is substituted with isophthalic acid (PCTA). Etc. can be used.
Moreover, as resin which comprises the handle | steering-wheel body 1a, resin which has moderate rigidity and toughness is preferable, and resin whose bending elastic modulus is 1900 MPa or more and tensile fracture strain is 80% or more is preferable. Here, the “flexural modulus” is a value measured according to ISO 178, and the “tensile fracture strain” is a value measured according to ISO 527-1,2.
If the flexural modulus is 1900 MPa or more and the tensile fracture strain is 80% or more, the toughness of the handle body 1a is sufficiently high, and even if the head portion 10 is thinned, it is difficult to break against impact, and the fracture surface Can be prevented from becoming an acute angle.
The upper limits of the flexural modulus and the tensile fracture strain are not particularly limited. However, in the case of a commonly used resin, the flexural modulus is 5000 MPa or less and the tensile fracture strain is 500% or less.
A polybutylene terephthalate resin is preferable in that the above-described bending elastic modulus and tensile fracture strain can be easily satisfied. Polybutylene terephthalate resin is excellent in chemical resistance and heat resistance. Therefore, the toothbrush 1 using the polybutylene terephthalate resin for the handle body 1a is less deteriorated even if it is used for a long time, and even if the bristle bundle 1b is firmly fixed by a flat wire, it is difficult to break, so that the quality becomes higher.
The polybutylene terephthalate resin is a thermoplastic polyester produced by a polycondensation reaction using terephthalic acid or dimethyl terephthalate and 1,4 butanediol as raw materials. For example, Juranex manufactured by Polyplastics, Mitsubishi Engineering Plastics Examples include NOVADURAN made by Toray Industries, and Toraycon made by Toray Industries.

The head part 10 is a substantially flat part, and the hair bundle 1b is implanted in a plurality of flock holes 11 provided on the flocked surface 10a. In the present embodiment, the flocked surface 10a of the head portion 10 has a substantially rectangular shape, both end edges 12 in the width direction are parallel to each other and along the longitudinal direction of the handle body 1a, and the end edge 13 on the most distal side is curved. Has been.

The thickness T of the head portion 10 is 2.0 to 4.0 mm, and preferably 2.5 to 3.5 mm. If the thickness T of the head portion 10 is less than 2 mm, the bending strength of the head portion is lowered, so that the head portion 10 may break during tooth brushing, and the hair bundle 1b is held with a flat wire. It is impossible to ensure a sufficient depth of the flock hole 11. On the other hand, when the thickness T of the head part 10 exceeds 4 mm, the intraoral operability becomes insufficient.
The shortest distance W between the outermost flock hole 11a in the width direction (direction perpendicular to the longitudinal direction) of the head portion 10 and the end edge 12 (hereinafter, this distance W is referred to as “the edge width W”). Is 0.4 to 0.9 mm, preferably 0.6 to 0.8 mm. When the edge width W of the head portion 10 is less than 0.4 mm, the head portion bending strength is insufficient, and the edge portion of the head portion 10 may be deformed due to stress caused by flocking. When the edge width W exceeds 0.9 mm, the edge width W becomes wider with respect to the thickness T of the head portion 10, and when the final molar is polished, the head portion 10 comes into contact with the gingiva or cheek mucosa and the operability is improved. It decreases and becomes uncomfortable.

Further, in the head part 10, it is preferable that the shortest distance between the flock hole 11b on the most distal side in the longitudinal direction of the head part 10 and the edge 13 on the tip side is 0.4 to 0.9 mm. If the shortest distance between the flock hole 11b and the edge 13 on the distal end side is less than 0.4 mm, the bending resistance of the head part may be insufficient, and if it exceeds 0.9 mm, the operability in the oral cavity may be reduced. There is.

The grip 20 is a rod-shaped part having a length that can be gripped by the user.
In the gripping part 20, the soft resin may be partially or wholly covered in order to improve gripping properties.
The soft resin is preferably a soft resin having a hardness (JISK6253 hardness test, test condition JIS A) of 5 to 100, and more preferably 20 to 60. If the hardness of the soft resin is 5 or more, it has sufficient softness and gripping properties are further improved.
Specific examples of the soft resin include polyolefin-based thermoplastic elastomer, polystyrene-based thermoplastic elastomer, polyurethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, 1,2-polybutadiene-based thermoplastic elastomer, ethylene-vinyl acetate-based thermoplastic. Examples thereof include elastomers, polyvinyl chloride thermoplastic elastomers, natural rubber thermoplastic elastomers, fluorine thermoplastic elastomers, and trans-polyisoprene thermoplastic elastomers.
When a polybutylene terephthalate resin is used as the resin constituting the handle body 1a, it is preferable to use a polyester-based thermoplastic elastomer as the soft resin from the viewpoint of compatibility. Examples of the polyester-based thermoplastic elastomer include Hytrel manufactured by Toray DuPont and Primalloy manufactured by Mitsubishi Chemical Corporation.

The neck portion 30 is a portion that connects between the head portion 10 and the grip portion 20. The width of the neck portion 30 is smaller than the width of the head portion 10. When the width of the neck portion 30 is smaller than the width of the head portion 10, the head portion 10 can be easily inserted into the oral cavity.

The bristle bundle 1b is constituted by a brush folded in half, and is fixed to the head portion 10 by driving a flat wire sandwiched between the brush folded in half into the flocked hole 11.
Examples of the material of the brush include polyamide (for example, nylon 6-12, nylon 6-10, 12 nylon, etc.), polyester (for example, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, etc.), polypropylene, elastomer, natural Examples include materials. Moreover, these materials may be combined.
The cross-sectional shape of the brush is not particularly limited, and examples thereof include a circular shape, a triangular shape, a quadrangular shape, a hexagonal shape, a petal shape, and an arc shape. Moreover, you may combine these shapes.
Further, the brush may be previously processed into a wave shape, a twist shape, a zigzag shape, or the like.

The outer diameter of the brush is preferably 3 to 15 mil (ie 0.076 to 0.381 mm), more preferably 5 to 10 mil (ie 0.127 to 0.254 mm).
Further, each brush may be normal hair having substantially the same diameter except for a rounded-end portion that is normally formed at the tip of the brush, or may be tapered hair whose outer diameter gradually decreases toward the tip. May be. These normal hairs and tapered hairs may be mixed, or may be changed for each flocked hole 11. Tapered hair has good penetration of the hair tip into a narrow gap, can realize soft contact feeling, and is suitable for brushing and massaging the tooth neck.
Examples of the tapered hair include a tapered hair having both ends tapered as described in JP-A-6-141923, and a taper processing only at one end as described in JP-A-57-50220. Tapered hair, taper hair in which a number of sharpened portions are formed on one hair as described in JP-A-2002-58838, sea island as described in JP-A-9-322821 Examples thereof include tapered hair having a structure, and tapered hair having a core-sheath structure as described in JP-A-2001-178542.

The length of the brush is preferably 7 to 15 mm, and more preferably 8 to 13 mm. Further, the lengths of the brushes may all be the same or not.
The brushing surface formed by the tips of the whole hair bundle 1b is, for example, a plane parallel to the flocked surface 10a; a plane inclined with respect to the flocked surface 10a; and gradually separated from the flocked surface 10a along the longitudinal direction. Alternatively, it can be a gradually approaching curved surface, convex surface, concave surface, or wavy uneven surface. From the viewpoint of ease of wiping, a flat or curved surface inclined so as to gradually approach the flocked surface 10a from the front end toward the rear end is preferable.

The length of the flat wire is preferably a length that can fix the brush reliably and does not cause cracking and whitening of the head portion 10. Specifically, a flat wire longer by 0.3 to 0.5 mm than the flock hole 11 is preferable.
The height of the flat wire is not particularly limited, but is preferably in the range of 0.9 to 2.0 mm in order to ensure flocking aptitude while ensuring sufficient driving strength. For the same reason, the thickness of the flat wire is preferably 0.20 to 0.25 mm.
In addition, the driving angle of the flat wire is appropriately selected, and in order to avoid the occurrence of cracking and whitening, a range of 5 to 80 ° with respect to the longitudinal direction of the handle body 1a is preferable, and a range of 15 to 30 ° is more preferable. preferable. The driving angle of the flat line may be the same for all the flat lines or may be different.
As the material of the flat wire, metal, plastic, or the like can be used, but metal is preferable and brass or aluminum is more preferable from the viewpoint of strength, productivity, and cost.
Grooves and fine irregularities may be formed on the surface of the flat wire in order to make it difficult to remove from the flock hole 11.

In the present embodiment, the flocked holes 11 are circular and are arranged in a grid pattern on the flocked surface 10 a of the head portion 10.
The shape of the flocked hole 11 in the depth direction may be a cylindrical shape whose shape does not change with respect to the depth direction, may be tapered such that the hole diameter decreases toward the bottom, The shape in which the level | step difference was formed in the middle may be sufficient. Moreover, the shape in which the level | step difference and the taper were each formed may be sufficient. Further, a chamfering process of about 0.3 mm may be performed on the bottom of the flock hole 11.
The diameter of the opening of the flocking hole 11 is preferably 1.0 to 2.0 mm (that is, the area is 0.75 to 3.1 mm ² ). By planting the hair bundle 1b in such a hole diameter, the contact with the gums is improved, and a toothbrush with a high feeling of insertion of the bristles into fine gaps such as interdental parts can be obtained.

In the toothbrush 1 described above, since the thickness T of the head part 10 is 2.0 mm or more and the edge width W is 0.4 mm or more, sufficient strength can be secured, and as a result, the head part bending strength is reduced. And appearance defects can be prevented. Moreover, in the toothbrush 1, since the thickness T of the head part 10 is 4.0 mm or less and the edge width W is 0.9 mm or less, the contact of the head part 10 with the oral cavity can be prevented. Excellent operability.
Moreover, in the toothbrush 1, since the hair | bristle bundle 1b is being fixed to the flock hole 11 with the flat line, it is hard to come off.

In addition, this invention is not limited to the said embodiment.
The head part 10, the grip part 20, and the neck part 30 do not need to be comprised with the same resin.
In addition, the head portion 10 is preferably within the above-mentioned range with the same thickness as in the above embodiment, but a part on the neck portion 30 side, preferably 1 of the length of the head portion 10. / 3 or less may be thick. By making the neck portion 30 side of the head portion 10 thick, the connection with the neck portion 30 can be made smooth.
Moreover, in the toothbrush of this invention, the neck part 30 may be abbreviate | omitted. That is, the handle body may be composed of the head portion 10 and the grip portion 20.
Moreover, the flocked surface 10a may not be substantially rectangular shape, for example, the head part 10 may be circular shape, elliptical shape, etc.

In addition to the circular shape, the shape of the opening of the flocking hole 11 may be, for example, a polygon such as a circle, a triangle, or a rectangle, or other shapes. Moreover, all the flock holes 11 may have the same opening shape, or two or more opening shapes may be combined.
The arrangement pattern of the flock holes 11 may be a staggered pattern, or a pattern in which an arc-shaped flock hole group that is curved toward the center side of the head portion 10 is formed at both ends in the width direction of the head portion 10. Good.
In the case of having the arc-shaped flock hole group as described above, the hair bundle 1b tends to be in close contact with the tooth neck. In terms of enhancing the feeling of brushing of the tooth surface, it is preferable that the hair bundle 1b planted in the arc-shaped flock hole group is longer than the hair bundle 1b planted in the flock hole other than the flock hole group. In that case, the difference in average brush length is preferably 0.3 to 2.0 mm, and more preferably 0.5 to 1.5 mm.
In the present invention, the hair bundle 1b itself can be formed in an arc shape, but in that case also, the hair bundle 1b is provided at both ends of the head portion 10 in the width direction, and the arc-shaped hair bundle 1b is used as the other hair bundle. It is preferable to make it longer than 1b.

In the following examples, the following resins were used.
Polybutylene terephthalate (PBT): NOVADURAN 5010 manufactured by Mitsubishi Engineering Plastics
Resin in which part of polycyclohexanedimethylene terephthalate is substituted with isophthalic acid (PCTA): BR203 manufactured by Eastman Chemical Co.
Polypropylene (PP): Prime Polymer Co., Ltd. J700GP
Polyacetal (POM): HC490 manufactured by Asahi Kasei Chemicals
Further, the flexural modulus of the resin used was measured according to ISO 178. The tensile fracture strain was measured according to ISO 527-1,2. The results are shown in Table 1.

(Examples 1 to 8, Comparative Examples 1 to 3)
By injection molding using the resin shown in Table 1, the hole diameter of the flocked hole is 1.55 mm, and the distance between the flocked holes is 0.725 mm. The thickness W, width L, and edge width W shown in Table 1 are as follows. A handle body having a head portion, a grip portion, and a neck portion was prepared.
Next, a hair bundle of a brush made of nylon (hair: 8 mil, length: 9.0 mm, flat cut) is folded in two, and a flat wire (width: 1.3 mm, length: 2.1 mm, (Thickness: 0.25 mm) was inserted and inserted into the flock holes formed in the head portion to plant hair bundles. Thereby, a toothbrush was obtained.
The oral operability, head part bending strength, bristle bundle holding strength and appearance of each obtained toothbrush were evaluated as follows. The evaluation results are shown in Table 1.

(1) Intraoral operability Ten test subjects actually used the toothbrushes of the examples and the comparative examples, and scored the operability of the toothbrush in the oral cavity according to the following criteria. And intraoral operativity was evaluated by the average value of 10 persons. The higher the score, the better the intraoral operability.
[Score based]
7 points: Very good.
6 points: Pretty good.
5 points: Somewhat good.
4 points: Neither.
3 points: Not good.
2 points: Not good.
1 point: Not very good.
[Evaluation criteria]
◎: Average value of 5.5 points or more ○: Average value of 5.0 points or more and less than 5.5 points △: Average value of 4.0 points or more and less than 5.0 points ×: Average value of less than 4.0 points

(2) Head part bending strength The part which protruded from the flocking hole of the brush of a toothbrush was cut | disconnected, and the flocked surface side of the head part was made smooth. Then, it fixed to the Izod impact test machine by Toyo Seiki Seisakusho Co., Ltd., impacted with the hammer from the flocked surface side, measured the impact energy when the head part broke (measurement number 10), and calculated the average value. . And it evaluated on the following references | standards. [Evaluation criteria]
○: Average value of 0.3J or more Δ: Average value of 0.15J or more and less than 0.3J ×: Average value of less than 0.15J

(3) Hair bundle retention strength All the brushes in one hole are gripped with a dedicated tool, and the maximum tensile stress (N) until the hair bundle comes out from the flock hole is measured using an autograph manufactured by Shimadzu Corporation (Tensile speed 20 mm / Minutes) (n = 20) and evaluated according to the following criteria. The higher the hair bundle holding strength, the more difficult it is to pull out the hair bundle.
[Evaluation criteria]
○: Average value 20N or more Δ: Average value 10N or more and less than 20N ×: Average value less than 10N

(4) Appearance Ten toothbrushes of each example and each comparative example were prepared, and the deformation of the edge of the head part, cracks, whitening and warpage were visually evaluated based on the following evaluation criteria.
[Evaluation criteria]
○: Occurrence rate of deformation, cracking, whitening and warping: 0%
Δ: Deformation, cracking, whitening, warping occurrence rate: less than 20% ×: Deformation, cracking, whitening, warping occurrence rate: 20% or more

The toothbrushes of Examples 1 to 8 in which the thickness T of the head part was 2.0 to 4.0 mm and the edge width W was 0.4 to 0.9 mm were excellent in intraoral operability. In particular, the toothbrushes of Examples 1 to 5 in which the handle body resin was polybutylene terephthalate resin had excellent appearance and had sufficient head part bending resistance. In addition, the toothbrushes of Examples 1 to 6 and 8 other than Example 7 in which the resin of the handle body was polypropylene resin had high bristle bundle holding strength.
On the other hand, the toothbrush of Comparative Example 1 in which the line width W of the head portion was less than 0.4 mm had a low head portion bending strength and an appearance defect.
The toothbrush of Comparative Example 2 in which the thickness T of the head part exceeded 4.0 mm and the toothbrush of Comparative Example 3 in which the line width W of the head part exceeded 0.9 had low oral operability.

The present invention is extremely useful industrially because it can provide a toothbrush in which the hair bundle is difficult to come out of the flock hole, is excellent in intraoral operability, and has sufficient strength.

DESCRIPTION OF SYMBOLS 1 Toothbrush

1a Handle body

1b Hair bundle 10 Head part

10a Flocking surface

11, 11a,

11b Flocking hole

12,13 Edge 20 Grasping part 30 Neck part

Claims

The hair bundle is provided with a substantially plate-like head portion provided with a plurality of flocked holes on the flocked surface, the bristles of a brush are folded in half, and a flat wire sandwiched therebetween is driven into the flocked holes so that the bristles are A toothbrush planted in a flocking hole,
The head portion has a thickness of 2.0 to 4.0 mm, and a toothbrush in which the shortest distance between the outermost flock hole in the width direction of the head portion and the edge is 0.4 to 0.9 mm.
The toothbrush according to claim 1, wherein the head portion is made of polybutylene terephthalate resin.