JPH10313944A - Inter-toothbrush and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inter-toothbrush and its manufacturing method which dispenses with any bending work of a wire part of a brush member, application of adhesive to the wire part, nor application of primer, and is provided with the wire part and a handle part superiorly stuck to each other. SOLUTION: A brush member 4 which is constituted of a brush part 2 formed by twisting bristle for a brush into a stainless steel wire and a linear wire part 3 extended from the brush part 2 is inserted into a metal mold by a prescribed length from the end of the wire part 3. The wire is embedded and stuck to the handle member 5 by injecting a thermoplastic synthetic resin containing metal adhesive polyolefin and insert-forming the handle member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interdental brush and a method for manufacturing the same. More specifically, the present invention removes plaque and the like in interdental spaces that cannot be removed by a normal toothbrush, prevents the occurrence of tooth decay in the interdental region, and causes periodontal disease in the interdental region. Prevent
The present invention relates to an interdental brush capable of massaging gingiva in an interdental region and a method of manufacturing the same.

[0002]

2. Description of the Related Art An interdental brush (10) has a brush portion (11) in which hair is twisted into a metal wire made of stainless steel or the like and a wire portion (12) made of a metal wire as shown in FIG. And a handle member (13) buried in length. For the handle member (13), a soft thermoplastic synthetic resin such as soft polyethylene such as low density polyethylene (LDPE), polypropylene (PP), or EVA (ethylene-vinyl acetate copolymer) is used alone or in a polymer blend. Is done. The wire portion (12) protrudes from the tapered portion (14) at the head of the handle member (13). An interdental brush (10) is inserted into an interdental space or the like of the back teeth for brushing. When it is necessary to bend the metal wire, it is possible to bend the bent portion (14) without reducing the radius of curvature of the metal wire, thereby preventing the wire portion (12) from breaking.

[0003] In the manufacture of the above-mentioned interdental brush (10),
A predetermined length is inserted into the mold from the end of the wire portion (12) of the brush member (15), and the above-mentioned thermoplastic synthetic resin is injected into the mold to simultaneously form the handle member (13). An insert molding method for integrating the handle member (13) and the wire portion (12) is usually employed. However, the adhesiveness between the thermoplastic synthetic resin and a metal wire such as stainless steel is hardly good, and when the embedded wire portion (12) is linear, the interdental brush (1) is used.
0), the handle member (1) of the interdental brush (10) is used.
When an external force such as rotating or pulling out the wire portion (12) embedded in 3) is applied, the wire portion (12) easily comes off from the handle member (13), and durability is improved. Becomes insufficient. Therefore, as shown in FIG. 2 (a), a part of the wire portion (12) is bent into a U-shape, or as shown in FIG. Is inserted into a mold and subjected to insert molding, so that the wire member (12) with respect to the handle member (13) is formed.
It is mainly performed to prevent the device from rotating or being pulled out. In order to bend the wire portion (12) into a U-shape or a U-shape, the brush member must be small,
Also, it is difficult to handle mechanically due to having hair, etc., and bending work etc. requires labor, and the work is fine, troublesome and difficult, it takes time and labor, and the cost increases due to bending work Is inevitable. further,
For the insert molding, it is necessary to manually insert the wire portion (12) bent in a U-shape or a U-shape into the mold, and the operation is troublesome, time-consuming, and costly. Become. Connect the straight wire to the handle (1
At the time of embedding in 3), it has been attempted to apply an adhesive to the wire portion (12) or apply a primer to the wire portion (12) to adhere to the thermoplastic synthetic resin. However, a pre-treatment step of applying an adhesive or a primer to the wire portion (12) is required, so that the cost is increased and satisfactory adhesion has not yet been obtained.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made as a result of intensive studies in view of the above-mentioned circumstances, and has been made by bending a wire portion of a brush member and applying an adhesive to the wire portion. It is an object of the present invention to provide an interdental brush that does not require application or application of a primer and has good adhesion between a wire portion and a handle member, and a method for manufacturing the brush.

[0005]

Means for Solving the Problems In order to solve the above problems, as an interdental brush of the present invention, a brush portion in which bristles for a brush are twisted from a tip into a metal wire over a predetermined length and a brush portion of the metal wire are provided. A brush member consisting of a straight wire portion, an interdental brush having a predetermined length embedded from a thermoplastic synthetic resin handle member from the end of the wire portion, wherein the handle member is at least a thermoplastic metal. A predetermined length from the end of the wire portion made of an adhesive synthetic resin and embedded in a handle member is adhered to the metal adhesive synthetic resin. It is preferable that the bonding between the linear wire portion of the metal wire and the metal adhesive synthetic resin is performed by insert molding. Thus, the linear wire portion can be adhered and integrated with the handle member only by molding.

As the thermoplastic metal-adhesive synthetic resin,
It is preferably a metal-adhesive polyolefin. Above all, it is a metal-adhesive polyolefin obtained by introducing a carboxylic acid into a very low-density polyethylene by a graft reaction, and has good adhesiveness with an embedded linear wire portion, good moldability, flexibility in use, and the like. This is desirable. The mechanism of adhesion between the metal-adhesive polyolefin and the metal is not clear, but the carboxylic acid introduced by the graft reaction and the oxide film on the metal surface and -OH in the sorbed water are not clear.
It is considered to be caused by causing a chemical bond or a hydrogen bond with a group or the like. The thermoplastic synthetic resin constituting the pattern member may be a metal-adhesive polyolefin alone or a polymer blend containing a metal-adhesive polyolefin. For the polymer blend, a thermoplastic synthetic resin as described later can be used, and the metal adhesive polyolefin is 5.6 parts by weight or more based on 100 parts by weight of the thermoplastic synthetic resin, so that the metal wire does not easily come out of the handle member. It is preferable to obtain a sufficient adhesive strength. If the metal-adhesive polyolefin is less than 5.6 parts by weight per 100 parts by weight of the thermoplastic synthetic resin, the adhesive strength between the metal wire surface and the handle member is inferior, which is not preferable. In particular, as the polymer blend, a combination of a metal-adhesive polyolefin, EVA, and soft polyethylene is preferable, and the metal-adhesive polyolefin is preferably 5 to 55 parts by weight, EVA 55 to 25 parts by weight, and soft polyethylene 10 to 35 parts by weight. .

[0007] The method of manufacturing an interdental brush according to the present invention is directed to a brush comprising a brush portion in which bristles for a brush are twisted over a predetermined length from a tip of a metal wire, and a linear wire portion of the metal wire. A predetermined length is inserted into the mold from the end of the wire portion of the member, and a thermoplastic synthetic resin containing at least a thermoplastic metal adhesive synthetic resin is injected into the mold to insert-mold the handle member. Then, the wire portion and the handle member are bonded together with the molding.

As the metal wire used in the present invention, stainless steel, titanium, titanium alloy, cobalt chromium, nickel chromium, iron, copper, aluminum and the like can be used, but stainless steel has good corrosion resistance and sufficient mechanical strength. It is preferable from the viewpoints of low cost and the like.

In the case where the metal-adhesive polyolefin alone is used as the thermoplastic metal-adhesive synthetic resin used in the present invention, a mold release agent is applied to the mold in order to improve the releasability after molding. Is preferred. In order to prevent sinking during molding, the injection speed may be reduced. When a polymer blend is used, the thermoplastic synthetic resin other than the metal adhesive polyolefin may be, for example, high-pressure low-density polyethylene (HPLDPE), very low-density polyethylene (VLDPE), or linear low-density polyethylene (LLDPE). Soft polyethylene, medium density polyethylene (MDPE), high density polyethylene (HDP)
E), ethylene vinyl alcohol copolymer (PVO)
H), ethylene-vinyl acetate copolymer (EVA), polypropylene (PP), ethylene ionomer, and the like. One or more of these thermoplastic synthetic resins other than the metal-adhesive polyolefin can be polymer-blended with the metal-adhesive polyolefin. The combination of thermoplastic synthetic resins in polymer blends is
Adhesion of metal-bonded polyolefin with metal wire does not alienate. Considering compatibility and miscibility of resin, mechanical properties such as bending strength of obtained handle member, biocompatibility, mold release Determined in consideration of moldability such as resistance and sink resistance, manufacturing cost, etc. It is necessary to select the mixing ratio in a range in which the adhesiveness to the metal wire can be sufficiently secured. When using a metal-adhesive polyolefin and another thermoplastic synthetic resin in a polymer blend, it is necessary that the metal-adhesive polyolefin is 5.6 parts by weight or more in 100 parts by weight of the thermoplastic synthetic resin. It is preferable to obtain a sufficient adhesive force that does not easily come off. Metallic adhesive polyolefin is thermoplastic synthetic resin 10
If the amount is less than 5.6 parts by weight in 0 parts by weight, the adhesive strength between the metal wire surface and the handle member is inferior, which is not preferable. As the polymer blend, metal adhesive polyolefin, E
By combining VA and soft polyolefin, the adhesiveness to the metal wire is sufficient, molding is possible without using a release agent, molding processability is good, and the handle It is preferable because appropriate flexibility can be obtained. In this case, as the polymer blend, a compounding ratio of 5 to 55 parts by weight of the metal adhesive polyolefin, 55 to 25 parts by weight of EVA, and 10 to 35 parts by weight of soft polyethylene is preferable. If the amount of the metal-adhesive polyolefin is less than 5 parts by weight, the adhesive force with the metal wire becomes insufficient, which is not preferable. If the amount exceeds 55 parts by weight, the adhesive force with the metal wire is sufficient, but the release agent is used during molding. It becomes necessary to do. In this case, the metal-adhesive polyolefin has an adhesive force to the metal wire and the releasability is particularly good up to 5 parts by weight or more and less than 10 parts by weight. The adhesive strength is particularly good, and the releasability and the formability are particularly good. When the amount is 20 parts by weight or more, the balance between the adhesiveness to the metal wire, the releasability, the formability, and the flexibility of the handle member is further improved. be able to. Among them, the most preferable compounding ratio is 30 parts by weight of the metal adhesive polyolefin, 45 parts by weight of EVA, and 25 parts by weight of soft polyethylene. Various methods such as a physical blending method by melting and a reactive processing method can be adopted for the polymer blend, but a physical blending method by melting is preferable in terms of uniform dispersion. In the physical blending by melting, it is preferable to use a single screw extruder or the like when the softening temperature and melt viscosity of the thermoplastic synthetic resin to be blended are close to each other, and the difference in softening temperature is large, and the melt viscosity is also high. If they differ greatly, it is preferable to use a twin screw extruder. The material blended with the polymer and extruded from the extruder is pelletized and subjected to insert molding. According to such a polymer blend, the amount of expensive metal-adhesive polyolefin used can be reduced, and a more inexpensive interdental brush can be provided. When using the metal-adhesive polyolefin alone, and when using as a polymer blend containing the metal-adhesive polyolefin, in any case, it is possible to add an inorganic pigment-based colorant, an auxiliary agent, a stabilizer, and the like. it can. The addition amount of the inorganic pigment-based colorant is preferably 1% by weight or less based on the thermoplastic synthetic resin constituting the pattern member.

In the method for manufacturing an interdental brush according to the present invention, it is preferable that the metal wire is degreased and its surface is cleaned as a pretreatment step. As the degreasing agent, methyl alcohol, ethyl alcohol, and a nonionic surfactant can be used. In particular, when stainless steel is used for the metal wire, ethyl alcohol is desirable.
It is not necessary to use a harmful organic solvent such as trichloroethylene which is usually used for cleaning the surface of stainless steel. The molding temperature, molding time, and molding pressure depend on the thermoplastic metal-adhesive synthetic resin used and / or the thermoplastic synthetic resin to be polymer-blended.

[0011]

Embodiments of the present invention will be described below, and the present invention will be described in more detail. Of course, the present invention is not limited by the following embodiments. In the following embodiment, the interdental brush (1) having the structure shown in FIG. 1 is formed by insert molding.
That is, as shown in FIG. 1, the interdental brush (1)
The wire portion of a brush member (4) comprising a brush portion (2) in which bristles for a brush are twisted from a tip into a stainless wire over a predetermined length and a linear wire portion (3) of the metal wire. A predetermined length from the end of (3) is embedded in a thermoplastic synthetic resin pattern member (5) using a metal-adhesive polyolefin. From the head (5a) of the handle (5), a tapered part (6) wrapping around the wire part (3) protrudes, and a knob is provided between the trunk (5b) and the tail (5c). The part (7) is provided in an annular shape. The outer diameters of the trunk (5b) and the tail (5c) are the same, so that they can be fitted and connected to a sleeve (not shown) as necessary. Therefore,
Insert the brush (2) into the sleeve, and insert the body (5
By fitting b), the interdental brush (1) can be kept in a storage state, and by fitting the tail (5c) to the sleeve, the interdental brush can be used in a state extended from the sleeve. it can.

[0012]

Next, the adhesion between the metal-adhesive polyolefin and the wire of the interdental brush will be described in more detail with reference to Examples and Comparative Examples. (Example 1) Metal-adhesive polyolefin obtained by grafting a carboxylic acid to ultra-low-density polyethylene as a thermoplastic metal-adhesive synthetic resin (trade name: Admer Grade XE-070: Mitsui Petrochemical Industry Co., Ltd.)
30 parts by weight, EVA (trade name; EVAFLEX P)
-1407: 45 parts by weight of Mitsui Dupont Chemical Co., Ltd., soft polyethylene (trade name: ULTZEX 202)
(00J: manufactured by Mitsui Petrochemical Industry Co., Ltd.) 25 parts by weight, and these were melted and kneaded at 230 ° C. for 2 hours and 30 minutes to obtain a polymer blend. A stainless wire having a diameter of 0.3 mm was used as a wire to be insert-molded, folded in the center into a pine needle shape, brush hairs were sequentially inserted from the bent portion, and radially implanted at a twist of 22 times / cm. Then, after the surface of the wire portion to be insert-molded is degreased with ethyl alcohol, the wire portion is inserted into a mold, and the polymer blend is injected and molded at a molding temperature of 180 ° C. and a molding time of 10 seconds, and molded.
The wire portion and the handle member were bonded together with the formation of the handle member. The embedded distance of the wire part in the handle member is 18.5m
m. The adhesiveness between the wire portion of the obtained interdental brush and the handle member was evaluated based on the pull-out resistance of the wire portion from the handle member. Pullout resistance is Autograph AGS
This was measured by a tensile test at a crosshead speed of 10 mm / min using -500D (manufactured by Shimadzu Corporation). The results are as shown in Table 1. The mechanism by which the stainless wire is bonded to the handle is not clear, but the hydrogen bond between the carboxylic acid introduced by the graft reaction in the metal-adhesive polyolefin and the passive layer on the stainless steel surface plays a major role. It is considered something.

(Example 2) [0013] The metal adhesive polyolefin of Example 1 was used alone for a handle member. The surface of a wire portion to be insert-molded was degreased with ethyl alcohol, and then the wire portion was molded into a mold. Insert into the 1
The metal-adhesive polyolefin was injected and molded at 80 ° C. for 20 seconds, and the wire member and the handle member were bonded together with the formation of the handle member. Prior to molding, a fluorine-based non-silicon type release agent was applied in the mold. The adhesiveness between the wire part and the handle member of the obtained interdental brush was evaluated by the same test method as in Example 1. The results are as shown in Table 1.

Comparative Example 1 4 parts by weight of the metal adhesive polyolefin used in Example 1, 35 parts by weight of EVA,
35 parts by weight of soft polyethylene was added at 230 ° C. for 2 hours 30
The mixture was melted and kneaded for a minute to obtain a polymer blend. After the surface of the wire portion to be insert-molded is degreased with ethyl alcohol, the wire portion is inserted into a mold, and the polymer blend is injected at a molding temperature of 185 ° C. and a molding time of 10 seconds to be molded, and the pattern member is formed. Was bonded to the wire portion and the handle member at the same time. The adhesiveness between the wire part and the handle member of the obtained interdental brush was evaluated by the same test method as in Example 1. The results are as shown in Table 1.

[0015]

[Table 1]

[0016]

Since the present invention is configured as described above in detail, it has the following effects. A brush member composed of a brush portion in which bristles for a brush are twisted over a predetermined length from a tip to a metal wire and a linear wire portion of the metal wire, wherein a predetermined length from the end of the wire portion is a thermoplastic synthetic resin. The handle member in the interdental brush buried in the handle member made of a product is made of at least a thermoplastic metal-adhesive synthetic resin, and has a predetermined length from the end of the linear wire portion of the brush member buried in the handle member. Since it is firmly adhered to the metal-adhesive synthetic resin, the use of the interdental brush causes an external force such as rotating or pulling out the wire portion embedded in the handle member of the interdental brush. Even if it is made to act, the wire portion does not easily come off from the handle member, and can be used for a long period of time. Therefore, there is no need to perform a fine, troublesome and difficult work such as bending a part of the wire portion embedded in the handle member into a U-shape or a U-shape, and the bending process can be omitted. Furthermore, even in insert molding, since it is only necessary to insert a linear wire portion into a mold, work is easy, work efficiency can be improved, and an inexpensive interdental brush is provided. Will do. Further, even when a straight wire portion is used as in the conventional technology, a step of applying an adhesive to the wire portion or a step of applying a primer to the wire portion is not required. In addition, since it is only necessary to degrease the metal wire to clean the surface and to subject the surface to molding, the operation is safe and easy, and the manufacturing cost of the interdental brush is not increased.

[Brief description of the drawings]

FIG. 1 is a partially broken plan view of an interdental brush of the present invention.

FIG. 2 shows a conventional interdental brush, in which (a) a wire portion is bent into a U-shape and embedded in a handle member;
(B) is a diagram in which the wire portion is bent into a dogleg shape and embedded in the handle member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Interdental brush 2 Brush part 3 Wire part 5 Handle member 7 Knob part

Claims (15)

[Claims] 1. A brush member comprising a brush portion in which a bristle for a brush is twisted over a predetermined length from a tip of a metal wire and a linear wire portion of the metal wire, a predetermined length from an end of the wire portion. In an interdental brush embedded in a handle member made of a thermoplastic synthetic resin, the handle member is made of at least a thermoplastic metal-adhesive synthetic resin, and has a predetermined length from an end of a wire portion embedded in the handle member. Is adhered to the metal-adhesive synthetic resin. 2. A brush member comprising a brush portion in which bristles for a brush are twisted over a predetermined length from a tip of a metal wire and a linear wire portion of the metal wire, a predetermined length from an end of the wire portion. In an interdental brush embedded in a handle member made of a thermoplastic synthetic resin, the handle member is made of at least a thermoplastic metal-adhesive synthetic resin, and has a predetermined length from an end of a wire portion embedded in the handle member. Are adhered to the metal-adhesive synthetic resin of a handle member formed by insert molding. 3. The thermoplastic metal-adhesive synthetic resin is a metal-adhesive polyolefin.
Or the interdental brush according to 2. 4. The interdental brush according to claim 3, wherein the metal-adhesive polyolefin is obtained by introducing a carboxylic acid into a very low density polyethylene by a graft reaction. 5. The thermoplastic synthetic resin constituting the handle member,
5. The interdental brush according to claim 3, which is a metal-adhesive polyolefin alone or a polymer blend containing the metal-adhesive polyolefin. 6. The interdental brush according to claim 5, wherein the metal-adhesive polyolefin is a thermoplastic synthetic resin.
An interdental brush characterized by being 5.6 parts by weight or more in parts by weight. 7. The interdental brush according to claim 5, wherein the thermoplastic synthetic resin is a metal-adhesive polyolefin.
Parts by weight, 55 to 25 parts by weight of EVA, soft polyethylene 1
An interdental brush comprising 0 to 35 parts by weight of a polymer blend. 8. The interdental brush according to claim 1, wherein the metal wire is made of stainless steel. 9. A brush member comprising a brush portion in which bristles for a brush are twisted over a predetermined length from a tip of a metal wire and a linear wire portion of the metal wire, a predetermined length from an end of the wire portion. Is inserted into a mold, a thermoplastic synthetic resin containing at least a thermoplastic metal-adhesive synthetic resin is injected into the mold to insert-mold the handle member, and simultaneously with the molding, the wire portion and the handle member are formed. A method for manufacturing an interdental brush, characterized by bonding. 10. The method for producing an interdental brush according to claim 9, wherein the thermoplastic metal-adhesive synthetic resin is a metal-adhesive polyolefin. 11. The method for manufacturing an interdental brush according to claim 10, wherein the metal-adhesive polyolefin is obtained by introducing a carboxylic acid into ultra-low density polyethylene by a graft reaction. Manufacturing method. 12. The interdental brush according to claim 10 or 11, wherein the metal adhesive polyolefin alone or a polymer blend containing the metal adhesive polyolefin is injected into a mold to insert-mold the handle member. Manufacturing method. 13. The method for manufacturing an interdental brush according to claim 12, wherein the metal-adhesive polyolefin is 5.6 parts by weight or more in 100 parts by weight of a thermoplastic synthetic resin. Method. 14. The method for producing an interdental brush according to claim 12, wherein the thermoplastic synthetic resin is a polymer blend of 5 to 55 parts by weight of a metal-adhesive polyolefin, 55 to 25 parts by weight of EVA, and 10 to 35 parts by weight of soft polyethylene. A method for manufacturing an interdental brush, comprising: 15. The metal wire is made of stainless steel,
The method for producing an interdental brush according to claim 9, wherein the method is inserted into a mold after degreasing.