JP2005185399A - Toothbrush - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toothbrush which has bristle bundles showing outstanding softness, bristles which make pleasant contact with teeth and oral soft tissues and shows increased ability to reach favorite sites of oral diseases such as a dental neck, interdental parts, and interdental cavities, and a smaller number of bristle bundles which are strong against the coming off of both bristle bundle and one bristle. <P>SOLUTION: In the toothbrush, the bristle bundle 4 in which a plurality of brushes 5 are bundled is planted in a transplanting hole 3 at a head part 1 by folding the bristle bundle 4 into two by using a flat line 6. The total cross-sectional area of the brushes 5 constituting the planted bristle bundle 4 is equal to or less than 1.0 mm<SP>2</SP>, and the packing factor is equal to or more than 50%. The surface roughness Ra of the inner wall surface 3a of the transplanting hole 3 is equal to or more than 4 μm and is equal to or less than 80 μm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a toothbrush having a small number of hair bundles capable of improving the flocking strength.

Conventional toothbrushes have 16 to 60 holes per hole, 32 to 120 holes per hole, and the total cross-sectional area of the brush is 1.0 mm ² in the flocked holes formed on the flocked surface of the toothbrush head at intervals of 1.0 mm or more. A thick bunch of brushes that are bound to exceed the width is fixed by driving in with a flat wire. In the case of such a toothbrush, since the bristle bundle is thick and the rigidity is high, there is a feature that the plaque removing power on the smooth surface and the mouth bite surface is particularly high.

  However, because the hair bundles are thick, the brushes that make up the hair bundles support each other, and the original supple movement of the brush itself cannot be demonstrated, and oral diseases such as the cervical part, interdental part, and interdental triangle are preferred. There is a problem that not only the hair tip does not easily reach the narrow part that is the origin, but the hair bundle tends to be hard, and the soft tissue such as gingiva is greatly stimulated.

  On the other hand, depending on the operation method, there may be a problem such as so-called single hair loss that occurs when a toothbrush is pulled out and one of the brushes in the hair bundle is caught between teeth. In the case of a conventional general toothbrush, in order to improve the hair bundle loss and single hair loss, the flat wire is driven deeply, or the flat wire size is increased to increase the allowance to the periphery of the flock hole. However, there are cases where the head portion cracks or whitens.

  Therefore, in order to solve such a problem, a metal flat wire is folded in half and driven and the metal is restored by a restoring force (Patent Document 1: Japanese Patent Laid-Open No. 2001-178537), a flat wire The both ends of the wire were bent and the frictional force with the outer peripheral portion of the flocked hole was ensured (Patent Document 2: JP 2000-296020 A), and a reduced diameter portion was provided in the flocked hole to increase the degree of adhesion with the brush. (Patent Document 3: Japanese Utility Model Laid-Open No. 5-68328) and the like have been proposed.

JP 2001-178537 A (the whole sentence, all figures) Japanese Unexamined Patent Publication No. 2000-296020 (full text, full figure) Japanese Utility Model Publication No. 5-68328 (full text, all figures)

As a result of previous experiments and researches, the present inventors have sufficiently demonstrated the flexibility of the hair bundle when the total number of cross-sectional areas of the brushes planted in one flock hole is 1.0 mm ² or less. It has been found that the contact with the teeth and soft tissues in the oral cavity is good and that the reach of the hair ends to the oral disease prone part such as the tooth neck part, interdental part and interdental triangle is high.

  Furthermore, by setting the packing factor (PF) of the brush bundle to 50% or more, preferably 50% or more and 80% or less, a more preferable specification can be obtained. The packing factor described here is a percentage (%) of the ratio of the total cross-sectional area of the brush that is fixed to the area of the flock hole excluding flat wires. When the packing factor is less than 50%, the fuzzing is worsened and the durability and the plaque removing function are deteriorated. Further, if it is close to 100%, there is a tendency that the fuzzing tends to be worse, and there is a possibility that the brush may be bent or the tensile strength may be lowered.

  However, in the case of a toothbrush with a small number of bristle bundles as described above, the number of brushes is small, so that the frictional force between the brushes cannot be fully exerted, and it is disadvantageous compared to a general toothbrush with respect to single hair removal. there were. When the driving of the flat line is deepened in order to prevent a single hair from coming off, there is a concern that the flat line directly hits each brush that has been planted and the brush is cut, and improvement is required.

  Moreover, since the method (patent document 2) which prevents the disconnection of the flat wire by increasing the frictional force between the flat wire and the flocking table is prevented from coming off the hair bundle, the shape of the flat wire is different from the normal one. Hair transplantation is difficult. Moreover, the method of providing a reduced diameter portion in the flocked hole (Patent Document 3) increases the degree of adhesion with the brush and prevents the hair from coming off, but still has problems in appearance such as poor fuzz.

  The present invention has been made to solve the above-mentioned problems, and has excellent flexibility of the hair bundle, good contact with the teeth and soft tissues in the oral cavity, oral diseases such as the cervical part, interdental part, and interdental triangle It is an object of the present invention to provide a toothbrush with a small number of hair bundles, which has high reachability of the hair tips to the frequently-occurring portions and is strong against both hair bundle loss and single hair loss.

In order to achieve the above-mentioned object, the present invention is a toothbrush in which a bunch of bundling a plurality of brushes is folded in half using a flat wire and planted in a flocking hole of the head portion, and the flocked hair bundle is configured. The total cross-sectional area of the brush is 1.0 mm ² or less, the packing factor is 50% or more, and the surface roughness Ra of the inner wall surface of the flocking hole is 4 μm or more and 80 μm or less, more preferably 10 μm or more and 60 μm or less. It is a thing.

  When the toothbrush has the above specifications, the frictional force between the brush and the inner wall surface can be sufficiently secured to improve the flocking strength, and not only the hair bundle but also the single hair can be prevented. Since toothbrushes with a small number of hair bundles have small flock holes and a large number of holes, normal flock pins tend to be difficult to come out when releasing after handle molding with a mold, but the surface roughness Ra is If the thickness is less than 4 μm, it is difficult to remove the pin, which may cause inconveniences such as breakage of the pin and difficulty in releasing when releasing the handle. Therefore, the surface roughness Ra is desirably 4 μm or more. On the other hand, when the surface roughness Ra exceeds 80 μm, the surface of the brush may be damaged or cut, which may cause a harmful effect at the time of flocking. Accordingly, the surface roughness Ra is desirably 80 μm or less. When the surface roughness Ra is 80 μm or less, it is possible to plant with a normal flat wire, so there is no need for a special device or the like, and there is no need to provide a reduced diameter portion for the planted hole. It has no effect on standing.

  The shape of the flocked hole is preferably a normal circular hole or a square hole, but it is desirable to have a shape having a major axis and a minor axis in the hair bundle, such as a substantially elliptical shape, a substantially oval shape, or a substantially rectangular shape. In addition, by combining the directions, it is possible to design the specifications according to the desired interproximal penetration, hair hitting feeling, and feeling of brushing. In addition, if the flock holes are arranged outward so that the short axis of the hair bundle can be seen, it looks finer than a circular hair bundle in which the same number of brushes are flocked, so the appearance discrimination can be significantly improved. . Also, in order to achieve a denser hole arrangement while avoiding interference between the flat wires, it is desirable that the arrangement of the flocked holes be staggered. Further, the outermost hair bundle of the head portion can be made to appear thin depending on the driving direction of the flat wire, and the appearance discrimination can be improved.

  Examples of toothbrush handle materials include polystyrene resin (PS), polypropylene resin (PP), polyethylene terephthalate resin (PET), acrylonitrile butadiene styrene resin (ABS), cellulose propionate resin (CP), polyarylate resin, polycarbonate resin ( Materials such as PC), acrylonitrile styrene resin (AS), polyacetal resin (POM), polybutylene terephthalate (PBT) can be used alone or in combination. It is also possible to provide a multicolor molded handle combined with thermoplastic elastomers. The handle material is not limited to the materials described above. Moreover, there is no restriction | limiting also about the shape of a toothbrush head part, a magnitude | size, and a design.

  As a brush material constituting the hair bundle, polyesters such as polyethylene terephthalate, polybutylene terephthalate and polytrimethylene terephthalate (PTT), polyamides such as nylon 6, nylon 66, nylon 6-10, nylon 6-12 and nylon 12, Materials that can be melt-spun, such as polyolefins such as polyethylene and polypropylene, and polyvinyl halides such as polyvinylidene fluoride are used, but nylon and polytrimethylene terephthalate (PTT) are preferred in terms of usability and durability. . Further, these materials can be used in accordance with the purpose, for example, by forming them into a double-core sheath shape to make brushes with different materials on the outside and inside, or brushes with different surface conditions.

  The thickness of the brush is 3 to 10 mils (0.076 to 0.254 mm), preferably 5 to 8 mils (0.125 to 0.203 mm). Usability, cleaning feeling, and cleaning effect These can also be used in combination in consideration of durability. In particular, the specifications with a large number of holes can be achieved by increasing the strength of the brush from the outside toward the center, or changing the properties of the brush (thickness, material, length, color, cross-sectional shape, etc.). Also, it is preferable in terms of feeling of use and appearance.

  Various types of brushes are used, such as normal round hair, taper hair, diamond hair, feather hair, other irregular cross-section hair, grainy hair, spiral catch hair, indicator hair, etc. be able to. However, the present invention is not limited to these.

  With regard to the shape of the brush, a master-slave shape such as a single flat shape, a mountain shape, or a concavo-convex shape can be adopted by arbitrarily setting the hair end (or profile) shape and the brush length of the free end. . Moreover, it is good also as a different structure by the outer side and inner side of a head part flocking surface, a front-end | tip part, and a rear-end part.

According to the present invention, the total cross-sectional area of the brushes constituting the hair bundle is 1.0 mm ² or less, the packing factor is 50% or more, and the surface roughness Ra of the inner wall surface of the flocking hole is 4 μm or more and 80 μm or less. As a result, it has excellent hair bundle flexibility, good contact with teeth and soft tissues in the oral cavity, and high reachability of hair tips to oral disease-prone parts such as the neck, interdental and interdental triangles. Moreover, it is possible to obtain a toothbrush with a small number of hair bundles that is strong against both hair bundle loss and single hair loss.

FIG. 1 shows an embodiment of the present invention.
In the figure, 1 is a head portion, 2 is a flocking surface, 3 is a flocking hole, 4 is a bunch of hair, 5 is a bristles constituting a bunch, 6 is a flat line, and a bunch of bundling a plurality of bristles 5 4 is planted by folding it into the flocking hole 3 of the flocking surface 2 of the head 1 using a flat wire 6. The total cross-sectional area of the brushes 5 constituting the hair bundle 4 implanted in the flock hole 3 is 1.0 mm ² or less, the packing factor is 50% or more, and the surface roughness of the inner wall surface 3a of the flock hole 3 is increased. Ra is 4 μm or more and 80 μm or less.

According to the above embodiment, the total cross-sectional area of the brush 5 constituting the hair bundle 4 planted in the tuft hole 3 is set to 1.0 mm ² or less. . Further, since the surface roughness Ra of the inner wall surface 3a of the flocked hole 3 is set to 4 μm or more and 80 μm or less and the packing factor is set to 50% or more, friction between the brushed brush 5 and the inner wall surface 3a of the flocked hole 3 is achieved. The force is increased, and not only the hair bundle 5 can be prevented from coming off, but also the single hair of each brush 5 can be prevented from coming off. As a result, the above effects combine to provide excellent hair bundle flexibility, good contact with the teeth and soft tissues in the oral cavity, and to oral disease prone parts such as the cervical part, interdental part, and interdental triangle. The toothbrush having a high reachability of the hair end and strong against both hair bundle loss and single hair loss can be obtained.

<Evaluation test>
A toothbrush shown in Table 1 (present inventions 1 to 4) was made as a trial, and evaluated for hair bundle strength, single hair dropout strength, and brush damage. As is clear from the evaluation results in Table 1, it was confirmed that the hair bundle strength, the single hair pull-out strength, and the brush damage were all excellent.

1. Experimental Method The roughness Ra of the inner surface of the flocked hole was measured as follows. The surface of the inner wall of the flocked hole was scanned from the bottom direction toward the opening with a laser microscope (manufactured by Keyence Corporation), and the surface roughness Ra was measured. Scanning was performed 3 times per site, and this was performed at 3 locations, and the average value was defined as the surface roughness Ra of the inner wall of the flocked hole.

2. Evaluation Method (1) Strength of Hair Bundle Grasping all brushes in one hole with a dedicated instrument, and measuring the maximum tensile stress (N) until the hair bundle comes out from the flock hole using an autograph manufactured by Shimadzu (Tensile speed 20 mm / And evaluated as follows according to the value.
◎: Average 25N or more ○: Average 20N or more △: Average 15N or more ×: Average less than 15N

(2) Single hair removal strength Grasp one of the brushes that has been implanted with a special instrument, and measure the maximum tensile stress (N) until the brush comes out of the flocked hole using an autograph made by Shimadzu (Tensile speed: 20 mm / And evaluated as follows according to the value.
◎: Average 5N or more ○: Average 3N or more △: Average 1.5N or more ×: Average less than 1.5N

(3) Brush damage state ○: Good, △: Slightly good, ×: Bad

FIG. 2 shows six types of specific configuration examples of the toothbrush according to the present invention.
Each of these toothbrushes has the above-described conditions of the present invention, that is, the total cross-sectional area of the brushes constituting the hair bundle planted in the flocked hole is 1.0 mm ² or less, the packing factor is 50% or more, and the flocked hole The surface roughness Ra of the inner wall surface is set so as to be 4 μm or more and 80 μm or less.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows an embodiment of a toothbrush according to the present invention, in which (a) is a schematic perspective view showing a relationship between a hair bundle and a flat line, (b) is a schematic plan view thereof, and (c) is an abbreviation of a flock hole. FIG. It is a figure which shows the specific structural example of the toothbrush which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Head part 2 Flocked surface 3 Flocked hole 3a Inner wall surface of flocked hole 4 Hair bundle 5 Brush 6 Flat line Ra Surface roughness

Claims (1)

In a toothbrush obtained by bundling a bundle of multiple brushes into two using a flat wire and planting them in a planting hole of the head, the total cross-sectional area of the brushes constituting the planted bundle is 1.0 mm. ^2. A toothbrush characterized by having a packing factor of 50% or more and a surface roughness Ra of the inner wall surface of the flocked hole of 4 μm or more and 80 μm or less.

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