JP6170802B2 - Handle body for toothbrush, manufacturing method thereof, and toothbrush - Google Patents

Description

  The present invention relates to a handle body for a toothbrush, a method for manufacturing the handle body, and a toothbrush.

As a toothbrush, what has a handle body provided with a handle part, a head part provided at the tip of the handle part, and a hair bundle planted in the head part is generally known. Usually, the handle portion is formed with a reduced neck portion, and a head is provided at the tip of the neck portion.
The toothbrush is required to improve operability in the oral cavity in order to make it easier to scrub the back teeth and the back side of the front teeth. Known toothbrushes that have improved operability in the oral cavity include those in which the head is made smaller, the head is made thinner, or the neck is made thinner.
In addition, a toothbrush is known in which the handle portion is covered with an elastomer resin to prevent a finger from slipping and the operability is improved.

Generally, a handle body of a toothbrush is made of polyolefin such as polypropylene (PP). If the head part of the PP handle body is simply thinned, the head part is likely to be damaged when the hair bundle is implanted with a flat-line type flock, the strength of the head part is reduced, and the head part is damaged during use. Problems such as becoming easier.
To solve such a problem, a toothbrush in which a hair bundle is implanted with a flat wire having a specific thickness has been proposed (for example, Patent Document 1).

Republished WO2005 / 060788

However, although the invention of Patent Document 1 can maintain the strength of the thinned head portion, if the neck portion is thinned, the strength of the neck portion becomes insufficient.
Polybutylene terephthalate (PBT), polyacetal (POM), and the like are known as high-strength resins, but PBT and POM have poor adhesion to elastomer resins. For this reason, when the handle body made of PBT or POM is covered with the elastomer resin, there is a problem that the shape of the covering portion made of the elastomer resin is limited and it is difficult to exert a sufficient anti-slip effect.
Furthermore, PBT and POM have poor adhesion to general-purpose plastics such as PP. Therefore, for example, even if a handle body having a head portion and a neck portion made of PBT or POM and a handle portion made of PP or the like is molded by insert molding, a member made of PBT or POM The member composed of PP is easily peeled off at the interface. When a member made of PBT or POM and a member made of PP or the like are individually molded and connected, there is a problem that the strength of the connecting portion is reduced or the manufacturing process becomes complicated.
As described above, when a different resin is used for each part, it is difficult to obtain a handle body having sufficient strength.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a handle body of a toothbrush that has two or more members made of different resins and has sufficient strength.

The handle body of the toothbrush of the present invention is a handle body of a toothbrush comprising a handle portion and a head portion provided at the tip of the handle portion, the first member made of a first resin, A second member made of a second resin different from the first resin, wherein the first member includes the head portion and an extending portion extending from the head portion toward the handle portion. The second member forms at least a part of the handle part, a part of the extension part is embedded in the second member, and the extension part intersects with the extension direction. A fitting portion protruding in a direction is formed, and the fitting portion is fitted with a fitting hole formed in the second member.
The fitting portion preferably passes through the fitting hole, and the first resin preferably contains at least one selected from polyester and polyacetal as a main component, and the second resin is The second member may be coated with a softer resin than the second resin.

  The toothbrush of the present invention is characterized in that a hair bundle is implanted in the handle body for the toothbrush of the present invention.

  The method for manufacturing a handle for a toothbrush according to the present invention is characterized in that the first member is disposed in a mold and the second resin is injected into the mold.

  According to the handle body of the toothbrush of the present invention, it has two or more members made of different resins and has sufficient strength.

(A) It is a top view of the toothbrush concerning one Embodiment of this invention. (B) It is a side view of the toothbrush concerning one Embodiment of this invention. (A) It is a top view which shows the 1st member of FIG. (B) It is a side view which shows the 1st member of FIG. (A) It is a top view which shows the 2nd member of FIG. (B) It is a side view which shows the 2nd member of FIG. (A) It is a top view which shows the coating | coated part of FIG. (B) It is a side view which shows the coating | coated part of FIG. It is a top view of the handle body concerning one Embodiment of this invention. It is a top view of the handle body concerning one Embodiment of this invention.

The toothbrush concerning one Embodiment of this invention is demonstrated with reference to FIGS. 1-4 below.
The toothbrush 1 in FIG. 1 includes a handle body for a toothbrush (hereinafter simply referred to as a handle body) 2 including a handle portion 20 and a head portion 10 provided at the tip of the handle portion 20. In the present embodiment, the handle portion 20 includes a grip portion 24 and a neck portion 22 that extends from the grip portion 24 and connects to the head portion 10.
A plurality of flock holes 12 are formed in the flocked surface 11 of the head portion 10, and hair bundles 14 for hair are planted in the flock holes 12.
In addition, illustration of the hair | bristle bundle is abbreviate | omitted in the top view of Fig.1 (a).

The handle body 2 includes a first member 4 that forms the head portion 10 and the neck portion 22, a second member 6 that forms the grip portion 24, and a covering portion 8 that covers a part of the second member 6. With.
In the vicinity of the neck portion 22 in the grip portion 24, a non-slip portion 82 having an elliptical shape in plan view is formed on the flocked surface 11 side (surface).

As shown in FIG. 2, the first member 4 is formed by integrally forming a head portion 10 and a substantially columnar extending portion 40 extending from the head portion 10. A second fitting portion 46 is formed at the tip of the extended portion 40, and a first fitting portion 44 is formed between the second fitting portion 46 and the head portion 10. The 1st fitting part 44 and the 2nd fitting part 46 protrude on the surface and its back surface. That is, the first fitting portion 44 and the second fitting portion 46 protrude in a direction that intersects the extending direction of the extending portion 40.
Since the fitting portion is formed in the extended portion 40, the first member 4 is difficult to come off from the second member 6.
A through hole 48 is formed in the extended portion 40 between the first fitting portion 44 and the second fitting portion 46. The through hole 48 penetrates from the front surface to the back surface.
In the extended portion 40, an annular recess 42 that circulates around the extended portion 40 is formed at a position corresponding to the boundary 5. By forming the annular recess 42, the first member 4 and the second member 6 can be more firmly connected.

In the first member 4, a portion from the annular recess 42 to the second fitting portion 46 is embedded in the second member 6, and is exposed from the boundary 5 to the head portion 10. That is, the boundary 5 is located at the base end of the neck portion 22, and the extended portion 40 is partially embedded in the second member 6, and the exposed portion forms the neck portion 22.
In the present embodiment, the first fitting portion 44 passes through the first fitting hole 64, and the second fitting portion 46 passes through the second fitting hole 66.

As shown in FIG. 3, a recess 62 is formed in the second member 6 at a position corresponding to the anti-slip portion 82.
A first fitting hole 64 is formed in the second member 6 at a position corresponding to the first fitting portion 44, and a second fitting is provided at a position corresponding to the second fitting portion 46. A hole 66 is formed.
A through hole 68 is formed in the second member 6 at a position corresponding to the through hole 48. The through holes 68 are opened in the front surface and the back surface of the second member 6.

As shown in FIG. 4, the covering portion 8 includes a covering main body 80 and a non-slip portion 82.
In the present embodiment, the covering body 80 is formed so as to cover the side surface and the back surface of the second member 6 from the boundary 5 to the rear end of the grip portion 24 and open the surface of the second member 6. ing. The anti-slip portion 82 is connected to the covering body 80 by a support portion 81 that passes through the through hole 48 and the through hole 68.

  The first member 4 is made of a first resin. In the present embodiment, the first resin is selected in consideration of the rigidity and mechanical characteristics required for the head portion 10 and the neck portion 22. Examples of the first resin include resins having a flexural modulus (JIS K7203) of 500 MPa or more and 3000 MPa or less. For example, polyester such as PBT, polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT); POM Polyolefins such as PP and polyethylene (PE); polystyrene (PS); acrylonitrile / butadiene / styrene resin (ABS), cellulose propionate (CP), polyarylate, polycarbonate, acrylonitrile / styrene copolymer resin (AS), etc. Can be mentioned. Among them, a resin mainly composed of one or more selected from polyester and POM is preferable, polyester and POM are more preferable, and PBT and POM are further preferable. Since polyester and POM have higher rigidity, sufficient strength can be obtained even if the head portion 10 is made thinner or the neck portion 22 is made thinner. These resins may be used alone or in combination of two or more. The “main component” means containing 50% by mass or more.

The second member 6 is made of a second resin different from the first resin. The difference from the first resin includes not only that the type and composition of the resin are different, but also that the type of additive is different and the color tone is different. In the present embodiment, the second resin is determined in consideration of the rigidity required for the grip portion 24, adhesiveness with the resin constituting the covering portion 8, and the like.
The second resin may be different from the first resin, and examples thereof include the same as the first resin. Among them, polyolefin is preferable, and PP is more preferable. If it is polyolefin, when the coating | coated part 8 is comprised with an elastomer resin, the adhesiveness of the 2nd member 6 and the coating | coated part 8 can be improved.

In this embodiment, as a combination of the first resin and the second resin, the first resin is a resin mainly composed of one or more selected from polyester and POM, and the second resin is a polyolefin. The first resin is preferably PBT or POM, and the second resin is PP. By adopting such a combination, the head portion 10 can be made thinner, the neck portion 22 can be made thinner, the operability in the oral cavity can be improved, and the adhesiveness between the grip portion 24 and the covering portion 8 can be improved.
Further, for example, the first resin may be a non-translucent resin and the second resin may be a translucent resin. By setting it as such a combination, the design variation of the handle body 2 can be diversified.

The covering portion 8 may be anything softer than the second resin (hereinafter sometimes referred to as soft resin). As the soft resin, for example, those having a Shore hardness A of 90 or less are preferable, and those having a Shore hardness A of 50 to 80 are more preferable.
Examples of the soft resin include elastomers (for example, olefin elastomers, styrene elastomers, polyester elastomers, polyurethane thermoplastic elastomers, etc.) and silicone.

The length of the handle body 2 is not particularly limited, and is, for example, 120 to 200 mm.
The width | variety of the head part 10 is not specifically limited, For example, 7-13 mm is preferable and 8-12 mm is more preferable. If it is more than the said lower limit, the area which implants the hair | bristle bundle 14 can fully be ensured, and if it is below the said upper limit, the operativity in an oral cavity can be improved more.
The length of the head part 10 is not specifically limited, For example, 10-30 mm is preferable and 12-28 mm is more preferable. If it is more than the said lower limit, the area which implants the hair | bristle bundle 14 can fully be ensured, and if it is below the said upper limit, the operativity in an oral cavity can be improved more.
The thickness of the head unit 10 can be determined in consideration of the material and the like, and is preferably 2 to 6 mm, and more preferably 2.5 to 4 mm. If it is more than the said lower limit, the intensity | strength of the head part 10 can be raised more, and if it is below the said upper limit, the operativity in an intraoral area will be improved more.
The thickness of the neck portion 22 can be determined in consideration of the material and the like, and is preferably 3 to 6 mm, and more preferably 3.5 to 4.5 mm. If it is more than the said lower limit, the intensity | strength of the neck part 22 can be raised more, and if it is below the said upper limit, the operativity in an intraoral area will be improved more.

The hair bundle 14 is a bundle of a plurality of hairs.
The length (hair length) from the flocked surface 11 to the tip of the hair bundle 14 can be determined in consideration of the hair and the like required for the hair bundle 14, and is, for example, 6 to 13 mm.
All the hair bundles 14 may have the same hair length or may be different from each other.

  The thickness (hair bundle diameter) of the hair bundle 14 can be determined in consideration of the hair and the like required for the hair bundle 14, and is set to, for example, 1 to 3 mm. All the hair bundles 14 may have the same hair bundle diameter or may be different from each other.

  As the hair constituting the hair bundle 14, for example, the diameter gradually decreases toward the hair tip, the hair having a sharpened hair tip (tapered hair), and the diameter from the flocked surface 11 toward the hair tip. Examples include hairs that are almost the same (straight hairs). Examples of the straight hair include those in which the hair tip is a plane substantially parallel to the flocked surface 11 and those in which the hair tip is rounded into a hemisphere.

The material of the hair is, for example, polyamide such as 6-12 nylon (6-12NY), 6-10 nylon (6-10NY), PET, PBT, polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), Examples thereof include polyesters such as polybutylene naphthalate (PBN), polyolefins such as PP, elastomer resins such as polyolefin elastomers and styrene elastomers.
These resin materials can be used singly or in combination of two or more.
Examples of the bristle include polyester bristle having a multi-core structure having a core and at least one or more sheaths provided outside the core.

  The cross-sectional shape of the hair is not particularly limited, and may be a circle such as a perfect circle or an ellipse, a polygon, a star, a three-leaf clover, a four-leaf clover, or the like. The cross-sectional shapes of all the hairs may be the same or different.

  The thickness of the hair can be determined in consideration of the material and the like. When the cross section is circular, for example, the thickness is 6 to 9 mil (1 mil = 1/1000 inch = 0.025 mm). Moreover, in consideration of a feeling of use, a feeling of cleaning, a cleaning effect, durability, and the like, a plurality of hairs having different thicknesses may be used in any combination.

In the manufacturing method of the toothbrush 1, the handle body 2 is formed by insert molding, and then the hair bundle 14 is implanted in the head portion 10.
In insert molding, the first member 4 is placed in a first mold, and a second resin is injected therein to obtain a substrate. The first member 4 is obtained by, for example, conventionally known injection molding. The first mold to be used has a cavity having a shape corresponding to the second member 6 with the first member 4 disposed therein. When the first member 4 is arranged in the first mold, the protruding ends of the first fitting portion 44 and the second fitting portion 46 come into contact with the inner surface of the first mold, so that the second resin When the first member 4 is injected, the first member 4 is not easily displaced. For this reason, the thickness of the 2nd member 6 which covers the 1st member 4 turns into desired thickness, and can join the 1st member 4 and the 2nd member 6 more firmly. The obtained base is in a state in which the fitting portion formed in the first member 4 is fitted in the fitting hole of the second member 6.

Next, the obtained base is placed in the second mold, and a soft resin is injected to obtain the handle body 2. In the second mold to be used, a cavity having a shape corresponding to the covering portion 8 is formed in a state where the base body is disposed inside.
The soft resin injected into the second mold fills the through holes 48 and 68 to form the covering main body 80 and the non-slip portion 82.

  Next, the hair bundle 14 is implanted into the head portion 10 of the obtained handle body 2. As a method for flocking the hair bundle 14, the hair bundle 14 is folded in half, and a flat wire sandwiched between the two is driven into the flock hole 12 to plant the hair bundle 14, and the lower end of the hair bundle 14 is flocked. A heat-sealing method in which the molten resin is pressed into and fixed in the molten resin, and an in-mold method in which the lower end of the hair bundle 14 is heated to form a molten lump and then the molten resin is injected into the mold to mold the flocked portion. Etc.

As described above, according to the handle body of the present embodiment, the first member and the second member made of different resins are provided and have sufficient strength. For this reason, for example, even if the first member is composed of high-rigidity PBT or POM and the second member is composed of PP having high adhesiveness to the elastomer resin, the first member and the second member Since it is difficult to separate, a handle body with high strength can be obtained.
In addition, in the handle body of the present embodiment, since the fitting portion is formed on the first member, it is difficult for the first member to come off from the second member.
Furthermore, since the fitting portion penetrates the fitting hole, that is, the fitting portion contacts the inner surface of the second mold, the first member does not shift when the second resin is injected. The first member and the second member can be joined more firmly.

The present invention is not limited to the above-described embodiment.
In the above embodiment, the boundary between the first member and the second member is located at the proximal end of the neck portion, but the present invention is not limited to this, and the boundary is located at the proximal end of the head portion. The boundary may be located in the middle of the neck portion, or the boundary may be located in the middle of the grip portion. That is, the extending part may not be exposed, may form a part of the neck part, or may form a part of the grip part.

  In the above-described embodiment, the base is composed of two members, the first member and the second member. However, this invention is not limited to this, For example, the base | substrate may be comprised with three or more members. For example, the base body may be configured by three members including a member constituting the head portion, a member constituting the neck portion, and a member constituting the handle portion. In addition, these three members may be made of different resins, or the two members may be made of the same resin.

  In the above-mentioned embodiment, although the fitting part is formed in two places of the extension part, this invention is not limited to this, The fitting part may be formed only in one place, 3 It may be formed at more than one place.

  In the above-described embodiment, the fitting portion protrudes in two directions, the front surface and the back surface. Good. Therefore, the fitting part may protrude only in one direction, may protrude radially, or may be formed in an annular shape. However, from the viewpoint of more firmly joining the first member and the second member, the fitting portion preferably protrudes in at least an arbitrary direction and the opposite direction.

  In the above-described embodiment, the fitting portion passes through the fitting hole. However, the present invention is not limited to this, and the fitting portion may not pass through the fitting hole. It may be covered with the second member. However, from the viewpoint of maintaining the posture of the first member in the mold, the fitting portion is preferably formed so as to penetrate the fitting hole.

In the above-described embodiment, the covering portion is formed so as to cover a part of the second member. However, the present invention is not limited to this, and the covering portion may not be formed. The entire second member may be covered, or the covering portion may cover the first member.
Moreover, a coating | coated part is suitably determined according to the design and function of a toothbrush.
For example, you may provide the coating | coated part 108 like the handle body 102 of FIG. The handle body 102 includes a head portion 110 and a handle portion 120, and the handle portion 120 includes a neck portion 122 and a grip portion 124. The first member 104 forms a head part 110 and a neck part 122, and the second member 106 and the covering part 108 form a grip part 124. The covering portion 108 is formed with two arcuate bulging portions 180 that bulge to the sides of the grip portion 124.
Or you may provide the coating | coated part 208 like the handle body 202 of FIG. The handle body 202 includes a head portion 210 and a handle portion 220, and the handle portion 220 includes a neck portion 222 and a grip portion 224. The first member 204 forms a head portion 210 and a neck portion 222, and the second member 206 and the covering portion 208 form a handle portion 220. The covering portion 208 is formed so as to cover one side surface of the grip portion 224 and open the other side surface, and a boundary 282 between the portion where the covering portion 208 and the second member 206 are exposed is oblique in plan view. Is formed. In addition, an exposed portion 280 in which the second member 206 is exposed in an elliptical shape in plan view is formed near the proximal end of the neck portion 222 in the handle portion 220 on the flocked surface 211 side (that is, the surface).

DESCRIPTION OF SYMBOLS 1 Toothbrush 2,102,202 Handle body 4,104,204 1st member 6,106,206 2nd member 8,108,208 Cover part 10,110,210 Head part 14 Hair bundle 20,120,220 Handle Part 40 Extension part 44 First fitting part 46 Second fitting part 64 First fitting hole 66 Second fitting hole

Claims (6)

In a handle body of a toothbrush comprising a handle portion and a head portion provided at the tip of the handle portion,
A first member composed of a first resin and a second member composed of a second resin different from the first resin;
The first member includes the head portion and an extending portion extending from the head portion toward the handle portion,
The second member forms at least a part of the handle portion,
A part of the extended portion is embedded in the second member,
The extending portion is formed with a fitting portion protruding in a direction intersecting with the extending direction,
The fitting portion is fitted with a fitting hole formed in the second member ,
The handle member for a toothbrush , wherein the second member is coated with a softer resin than the second resin .   The handle body for a toothbrush according to claim 1, wherein the fitting portion penetrates the fitting hole.   The handle body for a toothbrush according to claim 1, wherein the first resin contains at least one selected from polyester and polyacetal as a main component.   The handle body for a toothbrush according to any one of claims 1 to 3, wherein the second resin is polyolefin. A toothbrush, wherein a hair bundle is implanted in the toothbrush handle body according to any one of claims 1 to 4 . The handle member for a toothbrush according to any one of claims 1 to 4 , wherein the first member is arranged in a mold and the second resin is injected into the mold. Production method.

Images