JP2005253712A - Bristle for electric toothbrush and electric toothbrush - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bristle for an electric toothbrush effectively cleaning foreign matter and dental plaques stuck to teeth surfaces, clearances between teeth and molars, having an appropriate bristle elasticity non-damaging gingiva and having superior usability. <P>SOLUTION: This bristle for the electric toothbrush is composed of a core sheath type conjugated monofilament and, at least, the core part within a range of 0.5-6 mm from the end part of one end side is exposed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention can effectively clean the surface of the teeth, the gap between the teeth, the foreign matter and plaque adhering to the tooth decay, and has a moderate hairiness without damaging the gums. The present invention relates to an electric toothbrush bristle excellent in the above and an electric toothbrush in which this bristle is implanted in a flock hole of a base.

  In recent years, electric toothbrushes that have a brush part that reciprocates at high speed, rotates at high speed, or reverses at high speed by a motor driving force due to the superior cleaning of the tooth surface and the fact that they do not feel a burden even if they are brushed for a long time have been used. It is becoming popular on behalf of.

  As a form of bristles used for this electric toothbrush bristle, it was common to chamfer the end face of the cut bristle and round the hair tip, but recently, for the purpose of further improving the cleaning performance, Various forms such as a tip type, a taper type, and a tip crack type are taken. Among them, a bristle with a tapered tip and a bristle with a cracked tip are recognized to be effective, and has begun to be used in the electric toothbrush field.

  Specific examples of such a toothbrush bristle in which a tapered portion sharpened by chemical treatment is formed at the tip of a bristle made of a synthetic resin monofilament (for example, see Patent Document 1), and the taper of the filament tip with respect to the entire bristle length. There is known a toothbrush bristle (for example, refer to Patent Document 2) in which the ratio of the portion occupied is specified. However, when a bristle having a tapered tip is used for an electric toothbrush, interdental insertion is excellent. However, it is suitable as a brush to be used by people with weak gums due to the softening of the hair and hips due to the taper processing, but it is not suitable for those who require hair and waist similar to general toothbrushes. The problem is that the bristle material tends to spread as a result of pressing the hair ends against the teeth. Was Tsu. As a means to improve this, a method of increasing the outer diameter of the bristle to raise the hair and waist can be considered, but in this case, the tip becomes sharp and the hair and waist rises. Since it feels and hurts the gums, it was not a preferable means. Furthermore, since the electric toothbrush incorporates a rotation mechanism in the brush part, it is larger than a general toothbrush. Therefore, it is necessary to shorten the bristle so that the brush can easily enter the mouth. The thickening method tended to increase the tingling sensation compared to conventional toothbrushes.

In addition, a technique (for example, see Patent Document 3) that enables detailed cleaning using a bristle made of a composite monofilament having a tip divided into a plurality of fibers is also known. Since the single yarn diameter is reduced by splitting, the fluff at the tip is softened. There was a problem that the tip bristle material was likely to spread when applied, resulting in poor interdental insertability and poor durability.
JP-A-6-141923 Japanese Patent Laid-Open No. 2001-169828 JP-A-9-322821

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue.

  Therefore, the object of the present invention is to effectively clean the surface of the teeth, the gap between the teeth and the teeth and dental plaque adhering to the tooth decay as compared with the conventional electric toothbrush bristle, An object of the present invention is to provide an electric toothbrush bristle excellent in feeling of use without damaging gingiva while having moderate bristle and an electric toothbrush in which this bristle is implanted in a flock hole of a base.

   That is, in order to achieve the above object, according to the present invention, a bristle made of a core-sheath type composite monofilament, at least a core portion in a range of 0.5 to 6 mm is exposed from an end portion on one end side. An electric toothbrush bristle is provided.

In the toothbrush bristle of the present invention,
The core-sheath composite monofilament has a polyamide resin as a core component and a polyester resin as a sheath component; and the outer diameter of the core-sheath composite monofilament is in the range of 0.10 to 0.25 mm; and The cross-sectional area ratio of the core component and the sheath component is in the range of 30/70 to 90/10,
Are mentioned as preferable conditions.

  The electric toothbrush of the present invention is characterized in that the above-mentioned electric toothbrush bristle is implanted in a flock hole of a base.

  According to the present invention, as described below, the core of the brush tip is exposed, and since the outer diameter is thinner than the outer diameter of the flocked base, it is soft to the gums and can be used without damaging the gums. It is excellent, and it can effectively clean foreign matter and plaque adhering to the tooth surface, interdental teeth, and tooth decay, and the flocked base is composed of a core and a sheath, so there is enough waist and electric Even if the brush portion reciprocates at high speed or rotates at high speed and reverses by driving the motor of the toothbrush, a bristle for electric toothbrush and an electric toothbrush that are difficult to sag and have high durability can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an enlarged model view showing an example of a bristle for an electric toothbrush of the present invention, and FIG. 2 is a cross-sectional view taken along the line aa of FIG.

  As shown in FIG. 1, the bristle for an electric toothbrush of the present invention has a basic structure of a bristle 2 composed of a core-sheath type composite monofilament having a core part 3 and a sheath part 4, and at least 0.5 from an end part on one end side. It is an essential requirement that the core portion 3 in the range L of ˜6 mm is exposed.

  According to such a configuration, the portion close to the flocked base portion 2 of the electric toothbrush bristle has a two-layer composite structure of the core portion 3 and the sheath portion 4 over a certain length, and only the core portion 3 is on the tip side from that. Exposed for a predetermined length, the outer diameter of this part is thinner than the outer diameter on the flocked base 2 side, so the gums are soft and easy to use without damaging the gums. Can be cleaned. In addition, since the portion on the side of the flocked base is composed of a composite structure of the core portion 3 and the sheath portion 4, there is sufficient waist, and the brush portion reciprocates at high speed or rotates at high speed and reverses at high speed by the motor drive of the electric toothbrush. However, it is difficult to sag and has excellent durability.

  Here, it is important that the length L of the core portion 3 exposed at the tip of the bristle 1 is in the range of 0.5 to 6 mm, preferably 1 to 5 mm. If L is less than 0.5 mm, it becomes difficult for the hair tips to enter between the teeth and the gaps between the gums, and the effect of scraping off the dirt is reduced, and the waist of the hair tips becomes stronger and the soft feeling at the time of brushing is lost. Therefore, it is not preferable. If L exceeds 6 mm, there is a soft feeling, but the tip of the brush expands when the brush is pressed against the teeth when the brush part reciprocates at high speed or rotates at high speed or reverses like an electric toothbrush. This is not preferable because it is easy and interdental insertion properties are deteriorated and durability is also inferior.

  There is no restriction | limiting in particular about the cross-sectional shape of the said core-sheath-type composite monofilament, The thing of an appropriate shape is selected from circular, an ellipse, a multileaf shape, a polygon. It should be noted that the composite monofilament is optionally added with additives such as heat resistance, anti-glare agent, light-proofing agent, antioxidant, antistatic agent, antibacterial agent, colorant and plasticizer. It can be included.

  In the electric toothbrush bristle of the present invention, as a method of exposing the core portion at the tip, a known method such as a physical polishing process can be used in addition to a chemical process such as an alkali dissolution method. For example, in the case of chemical treatment, the core-sheath type composite monofilament is bundled in a straight line, the surroundings are protected with a tape or the like, cut into a necessary length, and then one end of the bristle bundle is immersed in an alkaline solution. By appropriately adjusting the concentration of the alkaline solution, the immersion temperature, the immersion length, the immersion time, etc., there is a composite part consisting of a core part and a sheath part of a certain length, and only the core part is on the further side. An exposed bristle can be formed.

  The core component and the sheath component of the core-sheath composite monofilament used in the electric toothbrush bristle of the present invention are not particularly limited and can be arbitrarily selected from thermoplastic resins capable of core-sheath composite spinning. Polyamide resins such as nylon 6, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12 and their interpolymers as the core component, and polyesters such as polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate as the sheath component The best effect is obtained when each resin is used. In other words, the use of polyamide resin as the core component ensures the strength of the waist as a brush, and the use of polyester resin as the sheath component eliminates alkali dissolution when exposing the deep part of the tip. This is because it is possible to employ a chemical treatment such as a method, and the tip core portion exposed portion can be easily formed.

  The outer diameter of the core-sheath type composite monofilament is 0.10 to 0.25 mm, preferably 0, in order to effectively clean the feeling of use as a toothbrush and dirt and to maintain the overall balance of brushing properties. It is preferable to set in the range of 12 to 0.23 mm.

  In the core-sheath type composite monofilament, the cross-sectional area ratio between the core component and the sheath component is desirably 30/70 to 90/10, preferably 40/60 to 80/20. When this cross-sectional area is 30/70 or less, the soft feeling is good, but not only the force for scraping dirt is reduced, but also the difference between the outer diameter and the tip core exposed portion is increased, and the sagability is deteriorated. A trend is invited. On the other hand, if the cross-sectional area ratio exceeds 90/10, it is difficult for the hair tips to enter between the teeth and the cleaning property tends to be lowered.

  Furthermore, it is desirable that the single yarn length of the bristle 1 to be flocked to the flocked base portion 2 of the base is in the range of 15 to 32 mm.

  The electric toothbrush obtained by flocking the bristle for the electric toothbrush of the present invention thus obtained in the flock hole of the brush base has a composite part consisting of a core part and a sheath part over a certain length from the flocked base part. On the tip side, only the core part is exposed for a predetermined length, so that the brush tip has a suitable soft feeling, is suitable for cleaning a periodontal pocket with weak gingiva, etc., and has an excellent feeling of use. Furthermore, when the brush part reciprocates at high speed or rotates at high speed or reverses like an electric toothbrush, the tip of the brush is difficult to spread and good interdental insertability can be maintained, as well as excellent cleaning. Effective and durable.

  Hereinafter, the present invention will be further described with reference to examples. The evaluation of bristle in the examples was performed by the following method.

[Rubber comfort]
We asked 15 monitors to evaluate the contact comfort on the gums when actually using an electric toothbrush, with 5 being very comfortable and 1 being totally uncomfortable, with 1 to 5 ranks. .

[Cleanability]
A pseudo tooth model is prepared by providing a groove of 1.0 mm between the two Acryli plates, and the pseudo tooth model is preliminarily stained with a dental occlusion check spray and then used for an electric toothbrush. Using an electric toothbrush manufactured from Bristle, brushing was performed under conditions of 3 minutes, the area that was cleaned after brushing was measured, and the percentage of the apparent dirt adhesion area was calculated and displayed.

[Spreading hair]
Brush the brush width before the electric toothbrush test by brushing under the condition of 2 hours using the electric toothbrush manufactured from the electric toothbrush bristle with the pseudo tooth model used in the above cleaning property. Displayed by calculating the percentage of

[Examples 1-3, Comparative Examples 1-2]
Nylon 610 is used for the core component, and polybutylene terephthalate (PBT) is used for the sheath component. A core-sheath composite monofilament with a core-sheath cross-sectional area ratio of 70/30 and an outer diameter of 0.200 mm is used. After producing a 28 mm-long fiber bundle, five types with different exposed lengths L of the core as shown in Table 1 can be obtained by changing the alkali concentration, treatment time, and immersion depth by a known alkali treatment method. Created a bristle.

  Table 1 also shows the results of characteristic evaluation of these bristle.

[Comparative Examples 3 and 4]
Using a PBT monofilament having an outer diameter of 0.200 mm, a bristle that was not tapered at the tip and a bristle that was tapered by the alkali treatment method of the same method of the example were prepared.

  Table 1 also shows the results of characteristic evaluation of these bristle.

  As is apparent from the results in Table 1, the electric toothbrush obtained by flocking the bristle for electric toothbrush of the present invention is excellent in balance between the contact feeling on the gums, the cleaning property and the spread of the hair.

  The electric toothbrush bristle and the electric toothbrush of the present invention can effectively clean foreign matter and plaque adhering to the tooth surface, the gap between the teeth and the tooth decay, and there is an appropriate bristle and hip. Since it is excellent in feeling of use without damaging the gums, it exhibits a new and effective effect not found in conventional electric toothbrushes.

It is an enlarged model figure which shows an example of the bristle front-end | tip for electric toothbrushes of this invention. It is the sectional view on the aa line in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Toothbrush bristle 2 Flocked base surface 3 Core part 4 Sheath part L Core part exposed length (mm)

Claims (4)

A bristle comprising a core-sheath type composite monofilament, wherein at least a core portion in a range of 0.5 to 6 mm is exposed from an end portion on one end side. 2. The electric toothbrush bristle according to claim 1, wherein the core-sheath type composite monofilament comprises a polyamide resin as a core component and a polyester resin as a sheath component. The outer diameter of the core-sheath type composite monofilament is in the range of 0.10 to 0.25 mm, and the cross-sectional area ratio between the core component and the sheath component is in the range of 30/70 to 90/10. The electric toothbrush bristle according to claim 1 or 2. An electric toothbrush comprising: the bristles for an electric toothbrush according to any one of claims 1 to 3 implanted in a flock hole of a base.

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