JP2001169829A - Bristle for toothbrush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bristle for toothbrush of making it possible to keep strength and cleaning property, heighten the frictional resistance against a tooth and remove foreign material and plaque attached on the gap between teeth without damaging the gum. SOLUTION: This bristle for toothbrush is composed of cut bristle of polyester monofilament. The polyester monofilament is formed to have a modified cross section shape and a taper part is formed on at least one end of the cut bristle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention enhances frictional resistance with teeth while maintaining excellent strength and cleanability, and effectively removes foreign substances and plaque adhering to the gap between teeth without damaging the gums. The present invention relates to a bristle material for a toothbrush that can be removed.

[0002]

2. Description of the Related Art In recent years, various forms of synthetic resin toothbrush bristle have been adopted, such as a round type, a tapered type, a tip-shaped type, and a cut-only type. It is considered that a hair material having a tapered hair tip is optimal for providing a function of more effectively removing foreign matter and plaque in a periodontal pocket.

[0003] The required characteristics of a toothbrush bristle having a tapered hair tip include a cut bristle made of a synthetic resin monofilament having a tapered tip, so that the cut bristle can easily enter between the teeth. First of all, it can be ensured. However, the conventional hair material for a toothbrush having a tapered hair tip has a relatively smooth surface because the tapered portion has a round cross section. There is a problem that the ability to remove dirt and foreign matter attached to the teeth, that is, the cleaning ability of the teeth is inferior.

[0004] As a bristle material for a toothbrush in which the above-mentioned problems have been solved, a tapered portion and smallpox-like and / or bellows-like irregularities in units of 100 µ are simultaneously formed on the tips of cut bristle made of a synthetic resin monofilament. Japanese Patent Application Laid-Open No. 8-47423 discloses a toothbrush bristle material in which the pitch of the concave and convex portions is one.
It is as large as about 00μ, and when this is applied to a toothbrush, the center diameter of the uneven part is about 200μ. Therefore, it is easy to cause breakage due to the uneven part, and it is not only inferior in strength and durability but also necessarily satisfactory. However, there is a problem that an ineffective plaque removing effect cannot be obtained.

On the other hand, sharpened synthetic fibers obtained by decomposing or dissolving one end of a synthetic fiber having a sharp ridge on the side surface are disclosed in JP-A-56-43471 and JP-A-56-43472. It is known that this sharpened synthetic fiber is intended for use in so-called animal hair substitutes such as writing brushes, and because it is thin and brittle, it cannot be applied to toothbrush bristle material at all. Met.

[0006]

SUMMARY OF THE INVENTION The present invention has been achieved as a result of studying to solve the problems in the prior art described above.

Accordingly, it is an object of the present invention to increase the frictional resistance with teeth while maintaining excellent strength and cleanability.
An object of the present invention is to provide a bristle material for a toothbrush capable of effectively removing foreign matter and plaque attached to a gap between teeth without damaging the gum.

[0008]

In order to achieve the above object, a bristle material for a toothbrush according to the present invention is a bristle material for a toothbrush comprising cut bristles of a polyester monofilament, wherein the polyester monofilament has an irregular cross section. The cut bristle has a length of 20 to 35 mm, and has a tapered portion formed at least at one end thereof.

In the bristle material for a toothbrush of the present invention, the cross-sectional shape of the polyester monofilament is flat or rectangular, and in this case, the diameter ratio of the cross-sectional shape of the polyester-based monofilament is expressed by major axis / minor axis. Is in the range of 1-4, and the minor axis is 0.1-
It is preferable that the diameter is 0.3 mm and the major axis is in the range of 0.1 to 1.2 mm.

[0010] In the bristle material for a toothbrush of the present invention, the polyester monofilament has a multi-lobed cross-sectional shape having a plurality of concave portions and convex portions. The degree of cross-sectional deformation represented by circumscribed circle diameter / inscribed circle diameter is in the range of 1.1 to 4.0, the number of convex portions is 3 to 8, and the circumscribed circle diameter is in the range of 0.12 to 0.30 mmφ. Preferably, there is.

Further, in the bristle material for a toothbrush of the present invention, it is desirable to form tapered portions at both ends of the cut bristle.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the bristle material for a toothbrush of the present invention will be described in more detail.

The material of the bristle material for the toothbrush of the present invention includes:
From the necessity of forming a tapered part, a polyester-based monofilament having the property of being easily hydrolyzed by an aqueous alkali solution, specifically, polyethylene terephthalate, polybutylene terephthalate, or a copolymerized polyester containing these as a main component, is prepared in a conventional manner. Therefore, the produced polyester-based monofilament is used.

The polyester-based monofilament may be a heat-resistant agent as long as the object of the present invention is not impaired.
Conventional additives such as weathering agents, plasticizers and colorants can optionally be included.

The bristle material for a toothbrush of the present invention is practically used in the form of a cut bristle obtained by cutting the above-mentioned polyester-based monofilament to a desired length. It is an important requirement that at least one end, preferably both ends, of the cut bristles are tapered.

The irregular cross-sectional shape of the polyester-based monofilament includes a flat and rectangular shape as shown in FIGS. 1A and 1B, or a multi-lobed shape as shown in FIGS. 1C to 1F.

When the irregular cross section is flat or rectangular,
The diameter ratio represented by the major axis / minor axis is in the range of 1 to 4, and the minor axis is 0.1 to 0.3 mm, and the major axis is 0.1 to 1.2 mm.
By setting in this manner, it is possible to obtain a bristle material for a toothbrush which has a moderately strong fiber stiffness and does not hurt the gums.

In the case of a multi-leaf shape having a plurality of concave and convex portions, the degree of cross-sectional deformation represented by circumscribed circle diameter / inscribed circle diameter is in the range of 1.1 to 4.0. Yes, the number of convex portions is 3 to 8, and the circumscribed circle diameter is 0.12 to 0.30
mm, and by setting in this manner, it is possible to obtain a toothbrush bristle which has excellent flocking properties when transplanting to a toothbrush and sufficiently satisfies a cleaning effect without reducing frictional resistance. . .

When the cross section of the polyester-based monofilament is a perfect circle or when the number of convex portions is more than 9 in a multi-lobed shape, an excellent tooth cleaning effect cannot be expected.

The length of the cut bristle in the present invention is appropriately selected depending on the type of the toothbrush to be applied, but is usually in the range of 20 to 35 mm, particularly preferably in the range of 25 to 35 mm.

The bristle material for a toothbrush of the present invention is characterized in that at least one end or both ends of a cut bristle having an irregular cross section is formed with a tapered portion.

That is, the bristle material for a toothbrush of the present invention is obtained by bundling a large number of cut bristles and treating one end or both ends thereof with a solvent typified by an aqueous solution of sodium hydroxide to form a large number of cut bristles. In this case, it is possible to perform a tapering treatment of a large amount of cut bristles at one time, and it is possible to obtain an excellent effect in the process.

The degree of tapering of the cut bristles by the solvent treatment may be, for example, 10 mm at the base of the tapered portion.
When it is 0%, the diameter at a position 1 mm from the tip of the taper is 35 ± 15%, and the diameter at a position 3 mm is 70 ± 20.
%, Preferably within a range of 85 ± 10% at the 5 mm position.

By tapering the tip with the solvent in this manner, in the case of a cut bristle having a rectangular or flat cross section, the tip of the tapered portion becomes linear, and a multileaf having a plurality of concave portions and convex portions is formed. In the case of a cut bristle having a cross-sectional shape, the tip of the tapered portion becomes dotted, but in any case, the straight portion and the tapered portion except for the tip of the tapered portion maintain the deformed cross-sectional shape as it is.

Therefore, when a toothbrush manufactured using the toothbrush bristle material of the present invention is used, the frictional resistance between the bristle material and the teeth is increased while maintaining strength and cleanability, and furthermore, the fine Since the insertability and reachability are further improved, foreign substances and plaque attached to the gap between the teeth can be effectively removed without damaging the gums.

There is no particular limitation on the method of manufacturing the toothbrush using the bristle material for a toothbrush of the present invention. For example, a method of bending the central portion of the cut bristle in the longitudinal direction and implanting it into the flocking hole of the toothbrush base. It can be manufactured by an ordinary method such as

[0027]

EXAMPLES The structure and effects of the present invention will be described in more detail with reference to examples.

The evaluation of each performance in the examples was performed according to the following methods. [Gingival Massage Effect] The results of sensory evaluation of the massage effect in the case of actually requesting the use of a toothbrush by 10 panelists are summarized as the following judgments 1 to 5.

Judgment: 1 ... Very good 2 ... Good 3 ... Normal 4 ... Small effect 5 ... No effect at all. [Interdental Insertion] The results of the sensory evaluation of the interdental insertion when a toothbrush was actually requested to 10 panelists were summarized as the following judgments 1 to 5.

Judgment: 1 ... The tip of the hair reaches the depth of the gap between the teeth and the cleaning property is extremely good. 2 ... The cleaning property is excellent. Can be inserted only a little in the gap. 5 ... The bristle tip cannot be inserted in the gap between the teeth. [Soft feeling] The sensory evaluation result of the soft feeling when a toothbrush was actually requested to 10 panelists was determined by the following judgments 1 to 4.
5

Judgment: 1 ... soft touch to the teeth and gums at the bristle tip and good use feeling 2 ... somewhat good to the usability 3 ... normal 4 ... hit to the teeth and gums at the bristle tip Slightly hard 5 ... The contact of teeth and gums on the bristle is hard and the feeling of use is poor. [Cleaning rate] A pseudo tooth model was prepared by providing a gap between two acrylic plates, and the gap of the groove was set to 0.0.
Three types (5 mm, 0.100 and 0.200 mm) were set (depth: 2 mm).

Apparent dirt was previously attached to the grooves of the model of the artificial tooth with a dental occlusion check spray (OCCULUDE), and brushing was performed under a load of 300 g for 3 minutes using a toothbrush manufactured from a bristle material for each brush. Was done.

The area that could be cleaned after brushing was expressed as a percentage of the apparent dirt area. [Examples 1 to 6, Comparative Examples 1 to 3] Polybutylene terephthalate having an intrinsic viscosity of 1.00 was used as a raw material, and this was melt-spun and stretched (drawing ratio × 4.5) according to a conventional method. An elliptical cross section of the short side 0.13 mm x long side 0.300 mm of the a shape shown in FIG. 1, the short side of the shape shown in FIG.
Polyester monofilaments each having a rectangular section having a long side of 0.20 mm and a multi-lobed section having an outer shape of 0.2 mm having c, d, e, and f shapes shown in FIG. 1 were obtained.

For comparison, a g-shaped polyester monofilament having an outer shape of 0.2 mm as shown in FIG. 1 and a multi-lobed cross-section having an outer shape of 0.2 mm having an h-shape shown in FIG. A) polyester monofilament was obtained.

Each of the obtained polyester monofilaments was wound into a bundle of 48 mm in diameter and cut into bundles of 30 mm. A cut bristle bundle (fiber bundle) was placed in a stainless steel basket with the fiber axis perpendicular to the bottom. Then, the basket is placed in a 40% by weight aqueous solution of sodium hydroxide adjusted to 110 ° C. so that one end of the fiber bundle is immersed and treated for 80 minutes. And the other end of the fiber bundle was immersed and treated similarly for 80 minutes. Next, the resultant was sufficiently washed with water, dehydrated, and dried to obtain a bristle having both ends tapered.

Next, the bristles having both ends tapered at the both ends obtained above were planted on a toothbrush base, and the results of the sensory evaluation and the cleanability of this toothbrush are shown in Table 1.

For comparison, a polyester monofilament having a multi-leaf cross section having a 0.2 mm outer shape and having a c-shape as shown in FIG. 1 was also evaluated when a non-tapered bristle was directly planted on a toothbrush base (Comparative Example). 3).

[0038]

[Table 1] As is clear from the results in Table 1, the bristle material for the toothbrush of the present invention (Examples 1 to 6) is compared with the bristle material for the toothbrush which does not satisfy the conditions of the present invention (Comparative Examples 1 to 3). In addition, the gingival massage effect, interdental insertion, softness and cleanability are balanced and excellent.

[0039]

As described above, according to the bristle material for a toothbrush of the present invention, while maintaining excellent strength and cleanability, the frictional resistance with the teeth is increased, and the teeth are not damaged. Since foreign matter and plaque attached to the gap can be effectively removed, it is possible to provide a toothbrush which is excellent in the cleanability of teeth and has an excellent massage effect on gingiva.

[Brief description of the drawings]

1a to 1e are cross-sectional views of a toothbrush bristle of the present invention, and FIGS. 1g and h are cross-sectional views of toothbrush bristle that does not satisfy the conditions of the present invention.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Junko Natsui 1 Kawara, Showa-cho, Okazaki City, Aichi Prefecture Toray Monofilament Co., Ltd. F-term (reference) 3B202 AA06 AB02 AB30 EA01 EB13 EB14 4L035 BB31 BB91 CC20 DD02 DD14 FF01 FF04

Claims (6)

[Claims] A toothbrush bristle comprising a polyester-based monofilament cut bristle, wherein the polyester-based monofilament has an irregular cross-sectional shape and the length of the cut bristle is 20 to 35 mm.
And a hair material for a toothbrush, wherein a tapered portion is formed at least at one end thereof. 2. The bristle material for a toothbrush according to claim 1, wherein the cross section of the polyester-based monofilament is flat or rectangular. 3. The cross-sectional shape of the polyester-based monofilament has a diameter ratio of major axis / minor axis of 1 to 4
The bristle material for a toothbrush according to claim 1 or 2, wherein the minor axis is in the range of 0.1 to 0.3 mm and the major axis is in the range of 0.1 to 1.2 mm. 4. The bristle material for a toothbrush according to claim 1, wherein said polyester monofilament has a multi-lobed cross section having a plurality of concave portions and convex portions. 5. In the cross-sectional shape of the polyester-based monofilament, the degree of cross-sectional deformation represented by circumscribed circle diameter / inscribed circle diameter is in the range of 1.1 to 4.0, the number of convex portions is 3 to 8, and The bristle material for a toothbrush according to claim 1 or 4, wherein the diameter of the circumscribed circle is in the range of 0.12 to 0.30 mmφ. 6. The bristle material for a toothbrush according to claim 1, wherein tapered portions are formed at both ends of the cut bristle.