JP2002159344A - Bristle for toothbrush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bristle for a toothbrush the cleaning effect of which on bacterial plaque is excellent, and at the same time, which has an excellent massaging effect without injuring the gingiva. SOLUTION: This bristle for the toothbrush is a cut bristle comprising a composite mono-filament having a core-sheath structure. For the core-sheath structure, a thermoplastic elastomer resin is used as the core component. Also, a crystalline polyester based resin or a crystalline polyamide based resin is used as the sheath component. In this case, an exposed section wherein the core component protrudes from the sheath component is formed on at least one distal end section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bristle for a toothbrush having a high frictional resistance with teeth, an excellent cleaning effect on plaque adhering to the tooth surface, and an excellent massage effect without damaging the gums. is there.

[0002]

2. Description of the Related Art The performance required for a bristle material implanted in a toothbrush is firstly a cleaning performance, that is, a performance of removing food debris clogged between teeth and plaque adhering to the tooth surface.
A bristle made of a synthetic resin monofilament is generally used as a bristle material that satisfies such cleaning performance.

[0003] Other required performances for a bristle for a toothbrush include having an appropriate rigidity, having a bending recovery property to withstand repeated use, and being excellent in durability. In order to satisfy the above, various studies have been made on the material polymer, shape or shape and filament diameter of the bristle.

For example, a bristle with a sharpened tip is
The insertability into the interdental area is high, and the effect of removing plaque in the gap is excellent. However, conventional sharpened bristle
Although the cleaning effect between teeth is high, the bristle is too weak to polish the surface of the tooth with a large cleaning area, and the contact area at the tip is small, so it has a sufficient cleaning effect to remove dirt and foreign matter. There was a problem that can not be.

In addition, a generally known bristle with a rounded tip cannot provide a satisfactory cleaning effect due to a small frictional resistance when polishing the tooth surface, and has a large rigidity to enhance the cleaning effect. Attempts to increase the filament diameter not only reduce the feeling of use but also tend to damage the gums.

[0006]

SUMMARY OF THE INVENTION The present invention has been achieved as a result of studying to solve the problems of the above-mentioned conventional toothbrush bristle.

Accordingly, an object of the present invention is to provide a bristle for a toothbrush which has a high frictional resistance with teeth, has an excellent cleaning effect on plaque adhered to the tooth surface, and has an excellent massage effect without damaging the gums. It is in.

[0008]

In order to achieve the above-mentioned object, a bristle for a toothbrush of the present invention uses a thermoplastic elastomer resin as a core component and a crystalline polyester resin or a crystalline polyamide resin as a sheath component. A cut bristle made of a composite monofilament having a core-sheath structure, wherein at least one end has an exposed portion where a core component protrudes from the sheath component.

In the bristle for a toothbrush according to the present invention, the composite monofilament has a core-sheath structure using a polyamide elastomer resin as a core component and a crystalline polyester resin as a sheath component. The weight ratio with the sheath component is 90/1
It is preferably in the range of 0 to 50/50, the projection length of the exposed portion is in the range of 0.5 to 5 mm, and the exposed portion is formed by mechanical polishing. Yes, when these conditions are applied, it is possible to expect to obtain an even better effect.

[0010]

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

The bristle for a toothbrush of the present invention has a basic structure of a cut bristle obtained by cutting a core-sheath composite monofilament into a desired length.

Here, the core / sheath composite monofilament is a material using a thermoplastic elastomer resin as a core component and a crystalline polyester resin or a crystalline polyamide resin as a sheath component.

Specific examples of the thermoplastic elastomer resin used as the core component include at least one of a polyester elastomer, a polyamide elastomer and a polyurethane elastomer.

As the above polyester elastomer,
It is formed from a polyester hard segment composed of a dicarboxylic acid component represented by terephthalic acid, a diol component represented by ethylene glycol, 1,4-butanediol and the like, and an aliphatic polyether soft segment having a molecular weight of 600 to 3000. Polyester ether block copolymers.

Further, as the polyamide elastomer,
Polyether amides obtained by condensation polymerization of a low molecular weight polyamide in a molten state, such as nylon 6, nylon 610, nylon 66, nylon 11, nylon 12, and nylon 612, and an oligomer of hydroxy polyether are exemplified.

Further, as the polyurethane elastomer, a bifunctional polyol constituting a soft segment;
A block copolymer composed of a combination of three components of a short-chain glycol and a diisocyanate constituting a hard segment is exemplified.

On the other hand, specific examples of the crystalline polyester resin used as the sheath component include polyethylene terephthalate, polybutylene terephthalate, and a copolymer mainly composed of these.

Specific examples of the crystalline polyamide resin include nylon 6, nylon 610, nylon 66,
Nylon 11, nylon 12, nylon 612 or a copolymer containing these as a main component.

The resin used as the core component and the sheath component in the present invention includes various additives such as pigments, dyes, light stabilizers, ultraviolet absorbers, antioxidants, crystallization inhibitors and plasticizers. It can be added in the polymerization step, after the polymerization, or immediately before spinning as long as the desired performance is not impaired.

In the above-mentioned core-sheath composite monofilament,
The weight ratio between the core component and the sheath component is 90/10 to 50/5.
0, and particularly preferably in the range of 80/20 to 60/40. When the ratio of the core component exceeds the above range, the bristle becomes not only too soft, but also the durability tends to be inferior, and conversely, less than the above range. In this case, the friction with the teeth is reduced, and the desired plaque cleaning effect cannot be obtained, which is not preferable.

The cross-sectional shapes of the monofilament and the core in the core-sheath composite monofilament need not necessarily be circular cross-sections, but it is most industrially advantageous to set the cross-section to a circular cross-section from the standpoint of manufacturing the nozzle. .

The diameter of the core-sheath composite monofilament is preferably set to a large diameter because the core component is made of a thermoplastic resin elastomer, which tends to be softened. Specifically, 0.1-0.5m
m, particularly preferably in the range of 0.2 to 0.4 mm.

In the bristle for a brush of the present invention, the above-mentioned core-sheath composite monofilament has a desired length, for example, 25-3.
It is practically used in the form of a cut bristle cut to a length of 5 mm. It is important that at least one end has an exposed portion where the core component protrudes from the sheath component. The exposed length of this exposed portion is 0.5 to 5 mm, especially 1
It is preferable to be in the range of ~ 3 mm, and by setting in this manner, the waist is moderately strong, and the exposed portion made of the thermoplastic elastomer resin which is the core component at the tip is exposed, thereby reducing gingiva. A bristle for a toothbrush that has an excellent massage effect without damaging it can be obtained.

In other words, if the core-sheath composite form in which no exposed portion is formed is used, although the plaque cleaning effect is excellent, the gingiva is easily damaged and a massage effect cannot be obtained, but the exposed portion made of a thermoplastic elastomer resin is formed. By taking advantage of the flexibility of the exposed portion and its thin wire diameter, it is possible to obtain an excellent massage effect without damaging the gingiva, and to remove the plaque in the gap between the teeth by the exposed portion. An effect can also be expected.

The method of forming the exposed portion includes a method by mechanical polishing using a polishing disk plate and a method by a chemical treatment for selectively dissolving only the sheath component resin. However, economically, a method using mechanical polishing is advantageous.

In particular, when the exposed portion is formed by mechanical polishing, it is preferable to use a bristle composed of a core-sheath composite monofilament using a polyamide elastomer resin as a core component and a polyester resin as a sheath component. This is preferable because it is easy to form the exposed portion.

The formation of the exposed portion may be performed in a bristle state, or may be performed after the bristle is planted on the toothbrush base.

The method for manufacturing a toothbrush using the bristle for a toothbrush of the present invention is not particularly limited. For example, a method of bending a central portion of a cut bristle in the longitudinal direction and implanting the cut bristle into a flocking hole of a toothbrush base. Can be produced by the usual method.

[0029]

EXAMPLES Hereinafter, the present invention will be further described with reference to examples. Each performance evaluation 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—Excellent massage effect 2—Good massage effect 3—Normal 4—Less massage effect 5—No massage effect [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 gingiva at the bristle tip and good use feeling 2 ... somewhat good to use feeling 3 ... normal 4 ... hit to the teeth and gingiva 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 property] Width between two acrylic plates A dummy tooth model is created by providing a groove-shaped gap of 2 mm, and apparent dirt is previously attached to the groove-shaped gap of the pseudo-tooth model with a dental occlusion check spray, and then a toothbrush manufactured from each toothbrush bristle is manufactured. Using, load: 300g,
The brushing was performed under the condition of 3 minutes, the area that could be cleaned after brushing was measured, and the percentage was displayed by calculating the percentage with respect to the apparent soil adhesion area. Example 1 A polyamide elastomer (A) was used as a core component.
TOCHEM 4033SN01), polybutylene terephthalate (Toray 1200S; intrinsic viscosity: 1.2) as a sheath component, and a core-sheath weight ratio of 70/30, and melt spinning by an extruder-type composite spinning machine.
After the spun yarn is extruded into water and solidified by cooling, the first stage: 60
3. Second stage in hot water of 120 ° C. in hot water of 120 ° C.
The film is stretched to 0 times in two steps, then subjected to relaxation heat treatment in a dry heat atmosphere, and wound up in a straight line to obtain a diameter of 0.25 mm.
Was obtained.

Next, the composite monofilament obtained above was bundled into a bundle diameter of 45 mm, cut into a length of 27 mm, and the cut end portions were polished with a polishing disk plate to obtain both ends. In each part, a cut bristle having an exposed part in which the core component protruded 1.0 mm from the sheath component was obtained.

Table 1 shows the results of evaluating the toothbrushes obtained by implanting the cut bristles thus obtained on a toothbrush base. [Examples 2 and 3] Two types of cut bristles were obtained under the same conditions as in Example 1 except that the lengths of the exposed portions at both ends of the bristles were changed to 0.6 mm and 4.0 mm. Was.

Table 1 also shows the results of evaluation of the toothbrushes on which the cut bristles were planted. [Examples 4 and 5] In Example 1, the weight ratio of the core and the sheath was changed to 85.
Except for changing to / 15 and 55/45, two kinds of cut bristles were obtained under the same conditions.

The results of evaluation of the toothbrushes on which the cut bristles were planted are also shown in Table 1. Example 6 A cut bristle was obtained under the same conditions as in Example 1 except that nylon 610 (M2001 manufactured by Toray Industries, Ltd., relative viscosity: 2.7) was used as a sheath component.

Table 1 also shows the results of evaluation of the toothbrushes on which the cut bristles were planted. [Comparative Example 1] In Example 1, instead of polishing both ends of the bristle, the both ends were cut at 0.2 mm.
Table 1 also shows the results of evaluation of toothbrushes implanted with cut bristles having a rounded tip in the range of (1). [Comparative Example 2] Polybutylene terephthalate (1 manufactured by Toray Industries, Inc.)
200S ... Intrinsic viscosity: 0.25m in diameter consisting of 1.2)
m is bundled into a bundle diameter of 45 mm, cut into 27 mm lengths, and the cut ends are immersed in an aqueous sodium hydroxide solution and subjected to a taper treatment to form 8.0 mm at both ends. Table 1 also shows the results of evaluations of toothbrushes in which cut bristles having a tapered range were planted. Comparative Example 3 A monofilament having a diameter of 0.25 mm made of nylon 610 (M2001 manufactured by Toray Industries, Ltd., relative viscosity: 2.7) was cut into a length of 27 mm.
Table 1 also shows the results of evaluating the toothbrushes on which the cut bristles in which the cut end portions of 0.2 mm were rounded were planted.

[0037]

[Table 1] As is clear from the results shown in Table 1, the toothbrush in which the cut bristles of the present invention are planted has excellent balance of massage effect, soft feeling (feeling of use) and cleanability.

[0038]

As described above, according to the bristle for a toothbrush of the present invention, the frictional resistance with the teeth is high and the plaque adhered to the tooth surface is excellent, and the gingival is not damaged. A toothbrush having a massage effect can be provided.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Junko Natsui 1 Kawara, Showa-cho, Okazaki-shi, Aichi F-term in Toray Monofilament Co., Ltd. 3B202 AA06 EA01

Claims (5)

[Claims] 1. A cut bristle made of a composite monofilament having a core-sheath structure using a thermoplastic elastomer resin as a core component and a crystalline polyester resin or a crystalline polyamide resin as a sheath component, and has at least one end portion. A bristle for a toothbrush, wherein the core component forms an exposed portion protruding from the sheath component. 2. The bristle for a toothbrush according to claim 1, wherein the composite monofilament has a core-sheath structure using a polyamide elastomer resin as a core component and a crystalline polyester resin as a sheath component. 3. The bristle for a toothbrush according to claim 1, wherein the weight ratio of the core component and the sheath component of the composite monofilament is in a range of 90/10 to 50/50. 4. A projection length of the exposed portion is 0.5 to 5 mm.
The bristle for a toothbrush according to any one of claims 1 to 3, characterized in that: 5. The bristle for a toothbrush according to claim 1, wherein the exposed portion is formed by mechanical polishing.