JP2016193086A - Brush device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brush device capable of improving a coupling strength between a brush member and a handle, preventing bristles from being bent by preventing an occurrence of stress concentration on the bristles, improving cleaning performance by improving properties of insertion into slit parts, and increasing the density in the tip of a brush part.SOLUTION: In a brush 1 in which a brush member 20 formed by integrally molding a plurality of pieces of bristles 21 on a base part 22 is provided integrally at the tip of a handle 10 by insert molding, a head part 11 is provided at the tip of the handle 10, a communication hole is provided at the head part 11 for communicating the front and rear surfaces, and a base front part 22a on the frond surface side of the head part 11, a base rear part 22b on the rear surface side of the head part 11, and a connection part 22c for connecting the base front part 22a and the base rear part 22b through the communication hole are provided to the base part 22.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a brush device suitable for a toothbrush having a brush member formed by integrally molding a plurality of bristles on a base portion.

  As a toothbrush, a flat toothbrush formed by planting a hair bundle formed by bundling a plurality of filaments in a plurality of planting holes formed in a hair transplant table using a flat wire (see, for example, Patent Document 1). Alternatively, a bundle of bundles of a plurality of filaments is set on a mold for forming the handle member, and the end of the bundle on the molding space side is heated and fused to form a roasted ball. A flat wire toothbrush (for example, see Patent Document 2) in which a handle member is injection-molded so that balls are insert-molded and a hair bundle is implanted in the handle member has been widely put into practical use.

  On the other hand, a handle member (handle) is manufactured by injection molding as a toothbrush that can be manufactured at a lower cost than a flat wire toothbrush or a flat wire toothbrush, and a plurality of bristles and the bristles against the flocking table of the handle member A toothbrush produced by insert-molding a brush member including a base portion that supports the base has been proposed and put into practical use.

  For example, Patent Documents 3 and 4 have a flocking table having bristles integrally formed with a flocking table, a first end portion and a second end portion, and the first end portion is connected to the flocking table. A neck portion and a handle portion having a front end portion and a rear end portion, the front end portion being connected to the second end portion of the neck portion, and the flocking table, the neck portion and the handle portion are made of the same plastic material; An integrally molded toothbrush has been proposed.

  In Patent Document 5, a brush member having a base plate and a plurality of bristles arranged upright on the base plate is manufactured, and the brush member is set in a mold for injection molding of a handle member. A toothbrush formed by insert-molding a brush member on a flocking table of a handle member is described.

  Further, as a toothbrush in which the tip end portion of the filament is configured in a tapered shape, the brush diameter at each part of 1 mm, 3 mm, 5 mm, and 8 mm from the taper tip portion of the filament is 25 to 35%, 55 to 70% with respect to the brush diameter of the base portion. %, 80 to 90%, and 90 to 100% have been proposed in which a hair-fed portion is formed by flocking a taper-shaped filament specified respectively (see, for example, Patent Document 6).

JP 2010-194044 A JP 2002-360343 A Special table 2002-508686 gazette Special table 2002-504001 gazette China Utility Model Announcement No. 201813193 Specification JP-A-6-141923

  In the toothbrushes described in Patent Documents 3 and 4, the bristles and the handle portion and the neck portion are made of the same synthetic resin material, but both have different required characteristics. For example, in order to improve the operability of the handle portion, the rigidity is high. If the material is used, the bristle will become too strong, causing problems such as easy damage to the gums during brushing and bending of the bristle from the root. On the other hand, if a soft material is used so that a soft feeling against gingiva is obtained, the rigidity of the handle part and the neck part is lowered, and the problem arises that the brushing operability is lowered.

  On the other hand, when the brush member in which the bristles are integrally formed on the base plate is manufactured as in the toothbrush described in Patent Document 5, and the insert member is insert-molded at one end of the handle member, the above-described problems can be solved. However, in the toothbrush described in Patent Document 5, since the base plate is not mechanically coupled to the flocking table, if the base plate and the handle member are made of different materials that are not compatible, the joint strength between the two There is a problem that it cannot secure enough. Moreover, in the toothbrush of patent document 5, since the bristles which comprise a brush member are thick compared with the filament of a flat wire toothbrush or a flat wire toothbrush, the insertion property between teeth inevitably falls, but patent document 5 In the toothbrush described above, the tip of the bristles is tapered, but the cleaning between the teeth cannot be sufficiently ensured. Since the other part is composed of a straight part perpendicular to the bristle planting surface, stress concentration is likely to occur at the base end of the bristle during brushing, etc., and the problem is that the bristle is easily bent from the root. is there. Furthermore, in the toothbrush described in Patent Document 5, since a plurality of bristles are erected substantially perpendicular to the flat base plate, the tip of the bristles is arranged on the center side of the front end of the brush part. As compared with a toothbrush in which bristles are provided in an inclined shape, the density of bristles at the tip of the brush part is reduced, so that the contact area of the brush part with the tooth neck part is reduced, and There is a problem that the cleaning property is lowered accordingly. Furthermore, since the front surface of the base plate (the surface on the bristle side) is flush with the front surface of the handle member, the outer periphery of the front surface of the handle member surrounding the base plate is removed when the mold is extracted from between the bristles after molding the brush member. It cannot be held and is difficult to release.

  The object of the present invention is to improve the bonding strength between the brush member and the handle, prevent the occurrence of stress concentration on the bristles, prevent bending of the bristles, improve the insertion property into the slit portion, and improve the cleanability. It is an object of the present invention to provide a brush tool that can be improved and can increase the density of the tip of the brush portion.

  A brush tool according to the present invention is a brush tool in which a brush member formed by integrally molding a plurality of bristles on a base part is integrally provided at the tip of a handle by insert molding, and the tip of the handle Provided with a head portion, a communication hole communicating with the front and rear surfaces of the head portion, a base front portion on the front side of the head portion, a base rear portion on the rear surface side of the head portion, and A connecting portion that connects the front portion of the base and the rear portion of the base through the communication hole is provided.

  In this brush tool, for example, after forming a handle, the handle is set in a mold for forming the brush member, and a brush member having a plurality of bristles and a base is inserted into the head portion of the handle. Since the brush device can be manufactured, the manufacturing cost of the toothbrush can be reduced when manufacturing a replacement brush for a manual toothbrush or an electric toothbrush compared to a flat toothbrush or a non-flat toothbrush. In addition, the head portion of the handle is formed with a communication hole that communicates the front and rear surfaces of the head portion, and the base portion of the brush member formed by insert molding includes a base front portion on the front side of the head portion, Since the rear part of the base on the rear surface side of the head part and the connecting part that connects the front part of the base and the rear part of the base through the communication hole are formed, the bonding strength of the brush member to the handle can be easily improved. In addition, since the brush member is bonded to the handle by mechanical connection, materials having compatibility with the handle and the brush member can be adopted, or those having no compatibility are used. Can also be adopted. When adopting materials that do not have compatibility, the degree of freedom of selection of the material constituting the handle and the brush member is increased, and both are configured with the optimum material corresponding to the required characteristics of the handle and the brush member. This is preferable.

  Here, on the first side of the bristles in the side view, at least two or more projecting arc portions having a center on the side of the second side are formed, and the base front surface over the entire length on the second side of the bristles. It is preferable to form an orthogonal straight line portion that is substantially orthogonal to. When two or more protruding arc portions are formed on the first side of the bristles in this way, stress concentration at the time of brushing can be prevented at least in the protruding arc portions, so that bending of the bristles can be prevented. Moreover, since the orthogonal linear part substantially orthogonal to the base front surface is formed in the 2nd side of a bristles over the full length, the metal mold | die structure which shape | molds a brush part can be simplified.

  In particular, as the projecting surface arc portion, a distal end side projecting arc portion is formed at the first end portion of the first side, and a proximal end projecting surface arc portion is formed at the proximal end portion of the first side, It is preferable to form a linear projecting-surface-side straight portion that is continuous with both projecting-surface arcuate portions on the first-side tip side portion. This is preferable because stress concentration during brushing can be prevented over substantially the entire length of the bristles, and bending of the bristles can be prevented.

  It is also a preferred embodiment to form a concave arc portion that is continuous with the front surface of the base at the base end portion on the first side in a side view of the bristles. In this case, stress concentration at the base end portion of the bristles can be prevented, and the bristles can be prevented from being bent from the root during brushing or the like.

  The bristles are tapered, and the ratio of the length from the tip of the bristles to the total length L of the bristles is such that the cross-sectional area at the 15% position is 10-20% of the cross-sectional area of the base end, and 25% In a preferred embodiment, the cross-sectional area at the position is set to 20 to 40% of the cross-sectional area of the base end portion, and the cross-sectional area at the 50% position is set to 60 to 80% of the cross-sectional area of the base end portion. By comprising in this way, the insertion property of the bristles of the bristles with respect to the slit portion can be improved. For example, in a toothbrush, the cleaning performance between the interdental portion and the tooth neck portion can be improved.

  It is preferable to form a flat surface substantially perpendicular to the longitudinal direction of the handle on the second side of the bristles. In this case, the molding surface of one mold for molding the bristles can be formed as a flat surface, and the releasability when the mold is released from the bristles can be greatly improved. Further, when the present invention is applied to a toothbrush, both sides of the flat surface become corners, so that plaque and the like adhering to the tooth surface can be scraped off at the corners, and cleaning performance can be improved.

  In the case where a flat surface is formed on the bristles as described above, the flat surface of the plurality of bristles provided on the base portion is formed only on the distal end side or the proximal end side in the longitudinal direction of the handle, or on the base end. It can provide in the front end side or base end side for every row | line | column of the bristle in a base part.

  It is a preferred embodiment that the tip of the bristles is formed into a partial spherical shape having a radius of 0.1 mm or more. By comprising in this way, the irritation | stimulation with respect to a body can be suppressed and the usability at the time of brushing can be improved. For example, when the present invention is applied to a toothbrush, it is possible to suppress irritation to gums and improve the feeling of use during brushing.

  In a preferred embodiment, the base front portion protrudes forward from the head portion within a range of 0.5 mm to 1.0 mm. If comprised in this way, since the outer periphery shaping | molding part which shape | molds the outer peripheral part of the protrusion part of a base front part is arrange | positioned between the metal mold | die which shape | molds bristles, and the outer peripheral part of a head part, the metal mold | die which shape | molds bristles is arranged. When releasing, it is possible to release the brush part first while holding the head part at the outer peripheral forming part, so that the release property of the brush tool can be improved.

  In a preferred embodiment, the tip width of the brush portion composed of the plurality of bristles is set to 75% or more and 95% or less of the base end width. In this case, it is possible to improve the cleaning performance of the slit portion by setting the density of the tip portion of the brush portion high. For example, when the present invention is applied to a toothbrush, it is possible to improve the cleanability of slit portions such as interdental portions and neck portions.

  The brush member can be made of an elastomer. In this case, it is possible to improve the feeling of use during brushing by suppressing irritation to the body. For example, when the present invention is applied to a toothbrush, irritation to gums can be reduced, and the feeling of use can be improved.

  In the above-described configuration, a brush member formed by integrally forming a plurality of bristles on the base portion is independently or arbitrarily combined with a brush tool that is integrally provided at the tip of the handle by insert molding. Can be provided. Further, the following configuration can be provided independently or in any combination with the above-described configuration.

  In a preferred embodiment, a fixing concave portion is formed on at least one of the front and rear surfaces of the head portion, and the base front portion or the base rear portion on the side where the fixing concave portion is provided is disposed in the fixing concave portion. If comprised in this way, in the toothbrush, the thickness of the hair transplant stand which consists of a head part and a base part can be made thin as much as possible, and the cleaning property of the back tooth which cannot brush easily can be improved.

  The handle is provided with a grip portion for gripping by hand, a neck portion for connecting the grip portion and the head portion, a fixing recess is formed on the rear surface side of the head portion, and the rear portion of the base is fixed Disposed inside the recess, extends in the longitudinal direction at the tip of the rear surface side of the neck, forms a recess for promoting deformation where the tip communicates with the fixing recess, and enters the recess for promoting deformation at the rear of the base It is a preferred embodiment to provide an extended elastic deformation promoting portion. The material of the brush member is softer and more flexible than the material of the handle, so by providing an elastic deformation promoting part connected to the back of the base at the tip of the rear side of the neck, the head The elastic deformation of the handle between the head and the neck can be promoted to improve the brushing operability, and the brushing pressure can be easily controlled.

  It is preferable to provide a mold gate for molding the brush member so as to correspond to the rear part of the base. Moreover, when providing the elastic deformation promotion part connected to the rear part of the base as described above, it is preferable to provide a mold gate for molding the brush member at a position corresponding to the elastic deformation promotion part.

  A frame portion constituting the outer peripheral portion of the head portion is provided, a longitudinal beam extending in the length direction at the center portion in the width direction of the head portion and having both ends connected to the frame portion is provided, and the length of the head portion One or a plurality of horizontal rails extending in the width direction in the middle of the vertical direction and having both ends connected to the frame portion are provided, and the vertical rails and the horizontal rails are provided in a lattice shape in the frame portion, and the communication hole A plurality of can also be provided in the head portion. By comprising in this way, the moldability of the base part of a brush member can be improved, ensuring sufficient strength rigidity of a head part.

  A cross section of the bristles can be formed in any one of a triangle, a trapezoid, a semi-circle, and a semi-oval. The cross section of the bristles can be formed in an arbitrary shape, but is preferably formed in any one of a triangle, a trapezoid, a semicircle, and a semioval in consideration of formability. Further, as bristles, bristles having different cross-sectional shapes, bristles having different cross-sectional dimensions at the same height position, and bristles having different hair lengths can be mixed. The bristle length is preferably 7.5 mm to 12 mm, and more preferably 8.5 mm to 11 mm.

  According to the brush device of the present invention, for example, after forming a handle, the handle is set in a mold for forming a brush member, and the head portion of the handle has a plurality of bristles and a base portion. Since the brush member can be manufactured by insert molding of the brush member, when manufacturing a replacement brush for a manual toothbrush or an electric toothbrush, the manufacturing cost of the toothbrush can be reduced as compared with a flat line toothbrush or a flat line toothbrush. In addition, the head portion of the handle is formed with a communication hole that communicates the front and rear surfaces of the head portion, and the base portion of the brush member formed by insert molding includes a base front portion on the front side of the head portion, Since the rear part of the base on the rear surface side of the head part and the connecting part that connects the front part of the base and the rear part of the base through the communication hole are formed, the bonding strength of the brush member to the handle can be easily improved. In addition, since the brush member is bonded to the handle by mechanical connection, materials having compatibility with the handle and the brush member can be adopted, or those having no compatibility are used. Can also be adopted. When adopting materials that do not have compatibility, the degree of freedom of selection of the material constituting the handle and the brush member is increased, and both are configured with the optimum material corresponding to the required characteristics of the handle and the brush member. This is preferable.

(A) Front view of toothbrush, (b) Right side view of toothbrush (A) is a front view of the brush part of a toothbrush, (a) is a bb line sectional view of Drawing 2 (a). Rear view of the head Sectional view along line IV-IV in Fig. 2 (a) (A) is a view of the bristles in the direction of the arrow Va in FIG. 2 (a) (b) is a view of the bristles in the direction of the arrow Vb in FIG. 2 (a); FIG. 2A is a view of the tip of the bristle as viewed from the arrow V in FIG. 2A, and FIG. (A) is a sectional view taken along line VII-VII of FIG. 5, and (b) to (d) are diagrams corresponding to FIG. 7 (a) of bristles having other configurations. (A) is a front view of a brush part in the toothbrush of another structure, (a) is the bb sectional view taken on the line of Fig.8 (a). Side view of brush part in toothbrush of other configuration (A) of the bristles of the toothbrush of Example 2 is equivalent to FIG. 5 (a), and (b) is equivalent to FIG. 5 (b). (A) of the bristle of the toothbrush of Example 3 is equivalent figure of Fig.5 (a), (b) is equivalent figure of FIG.5 (b). (A) of the bristles of the toothbrush of Comparative Example 1 is equivalent to FIG. 5 (a), and (b) is equivalent to FIG. 5 (b). (A) of the bristles of the toothbrush of Comparative Example 2 is a diagram corresponding to FIG. 5 (a), and (b) is a diagram corresponding to FIG. 5 (b). Side view of bristles of toothbrush of comparative example 3 FIG. 5A is a view corresponding to FIG. 5A and FIG. 5B is a view corresponding to FIG. (A) (b) is explanatory drawing of how to make load act on bristles In Example 1, (a) is explanatory drawing which shows stress distribution when pressing the 2nd side front-end | tip part, (b) is explanatory drawing which shows stress distribution when pulling the 2nd side front-end | tip part. In Example 3, (a) is explanatory drawing which shows stress distribution when the 2nd side front-end | tip part is pressed, (b) is explanatory drawing which shows stress distribution when the 2nd side front-end | tip part is pulled. In Comparative Example 1, (a) is an explanatory view showing the stress distribution when the second end is pressed, and (b) is an explanatory view showing the stress distribution when the second end is pulled. In Comparative Example 5, (a) is an explanatory diagram showing the stress distribution when the second side tip is pressed, and (b) is an explanatory diagram showing the stress distribution when the second side tip is pulled.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, the brush device of the present invention is applied to a manual toothbrush.

  As shown in FIGS. 1 to 7, the toothbrush 1 is integrally formed with a base portion 22 with a rod-shaped handle 10 as a handle and a plurality of bristles 21 provided on a head portion 11 at the tip of the handle 10. And the brush part 2 is formed by the head part 11 and the brush member 20.

  The brush member 20 is attached to the handle 10 by insert-molding the brush member 20 into the head portion 11 of the handle 10 in a state where the handle 10 previously formed by injection molding is set in a mold for forming the brush member 20. It is attached by that. However, it is also possible to manufacture the brush member 20 in advance, set the brush member 20 in a mold for forming the handle 10, and insert-mold the handle 10 into the brush member 20. It is also possible to manufacture the handle 10 and the brush member 20 separately, and attach the brush member 20 to the tip portion of the handle 10 by concavo-convex fitting or forced fitting with respect to the head portion 11 of the handle 10.

  The handle 10 includes a grip part 12 for gripping by hand, a neck part 13 having a smaller cross section than the grip part 12 extending from the grip part 12 toward the tip part side, and a head part 11 provided at the tip part of the neck part 13. It is integrally formed by injection molding using a synthetic resin material. In addition, it is possible to arbitrarily configure the handle 10 other than the head portion 11. For example, the grip portion 12 is provided with a non-slip portion made of elastomer by molding, or the design is improved by ink jet or pad printing. Can also be used.

  As the synthetic resin material constituting the handle 10, for example, polypropylene, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polytrimethyl terephthalate, polycarbonate, polyoxymethylene, styrene / acrylonitrile resin, acrylonitrile / butadiene / styrene resin, Hard synthetic resin materials such as cellulose propionate, polyamide, polymethyl methacrylate, polyarylate, etc. can be used.

  The head portion 11 has an annular frame portion 11a that is elongated in the length direction constituting the outer peripheral portion, and extends in the length direction to the center portion in the width direction of the head portion 11, and both ends are connected to the frame portion 11a. A vertical bar 11b and four horizontal bars 11c extending in the width direction of the head part 11 from the middle part in the length direction of the vertical bar 11b and connected to the frame part 11a. A front fixing concave portion 11d is formed on the front side of the head portion 11, a rear fixing concave portion 11e is formed on the rear surface side of the head portion 11, and front and rear fixing concave portions 11d and 11e are formed in the frame portion 11a. Six communication holes 11f communicating with each other are formed by the vertical beam 11b and the horizontal beam 11c. In addition, the outer edge shape of the frame part 11a can be arbitrarily set according to the shape of the known flocking table of the toothbrush 1 or the like. Further, the number, width, and thickness of the vertical bars 11b and the horizontal bars 11c, and the formation position of the head portion 11 in the thickness direction can be arbitrarily set. Furthermore, although the fixing recesses 11d and 11e are preferably provided on the front and rear surfaces of the head portion 11, they can be provided only on one side.

  A continuous portion 13a that is configured to increase in width toward the distal end side is formed at the distal end portion of the neck portion 13 so as to be smoothly connected to the head portion 11, and the length direction of the neck portion 13 is formed on the rear surface side of the continuous portion 13a. The deformation promoting recess 13b is formed so that the front end communicates with the rear fixing recess 11e. The width, length, and depth of the deformation promoting recess 13b can be arbitrarily set within a range in which the neck 13 is not damaged by a load during brushing. However, the deformation promoting recess 13b can be omitted as shown in FIG.

  The brush member 20 is formed integrally with the handle 10 by insert molding, with the head portion 11 of the handle 10 manufactured in advance set in a mold for forming the brush member 20, and the brush portion including a plurality of bristles 21. 2 and a base portion 22 that fixes the base end portions of the plurality of bristles 21 constituting the brush portion 2 to the head portion 11. The base part 22 includes a base front part 22a on the front surface side of the head part 11, a base rear part 22b on the rear surface side of the head part 11, and a connecting part 22c that connects the base front part 22a and the base rear part 22b. The base front portion 22a on the front side of the vertical rail 11b and the horizontal rail 11c and the base rear portion 22b on the rear surface side are connected by the connecting portion 22c, so that the head portion 11 is mechanically connected. Yes. The plurality of bristles 21 constituting the brush part 2 are integrally provided on the front surface of the base front part 22a so as to protrude forward.

  The material constituting the brush member 20 may be composed of a synthetic resin material that is compatible with the synthetic resin material that constitutes the handle 10, but is compatible with the material because the materials that can be used are limited. It is preferable to use a material that does not. For example, synthetic resin materials such as polyolefin resins such as low density polyethylene, polypropylene and metallocene-based soft polypropylene, nylon resins such as 6 nylon, 6-6 nylon, 6-10 nylon, 6-12 nylon, and styrene It is possible to employ thermoplastic elastomers such as olefins, polyamides, polyesters, and polyurethanes, and thermosetting elastomers such as silicon rubber, urethane rubber, fluorine rubber, natural rubber, and synthetic rubber.

  The base front portion 22a is accommodated in a front fixing recess 11d on the front side of the head portion 11 so as to protrude forward from the head portion 11, and the base rear portion 22b is a rear fixing recess on the rear side of the head portion 11. 11e is housed so as not to protrude rearward. The protrusion height H of the base front portion 22a from the head portion 11 can be arbitrarily set. For example, the height H is set to 0.5 mm or more and 1.0 mm or less. 11 is arranged between the outer peripheral portions of the base front portion 22a, and when the mold for molding the bristles 21 is released, the outer peripheral molded portion is used as a head portion. Since it becomes possible to release while holding 11, the releasability of the toothbrush 1 can be improved.

  The base rear portion 22b is integrally provided with an elastic deformation promoting portion 22d extending into the deformation promoting recess 13b of the neck portion 13 with the base rear portion 22b. By this elastic deformation promoting portion 22d, a handle between the flocking table and the neck portion 13 is provided. The elastic deformation in the front-rear direction of 10 can be promoted to improve the brushing operability, and the brushing pressure can be easily controlled.

  The bristles 21 can be provided so as to protrude forward so as to be substantially orthogonal to the front surface of the base front part 22a (the bristles standing surface), but the tip of the bristles 21 extends in the width direction of the brush part 2. As shown in FIG. 4, the tip end width WT of the brush part 2 is configured to be 75% or more and 95% or less of the base end width WR. . The distal end width WT of the brush portion 2 may be set to be the same as the proximal end width WR. However, if the distal end width WT is set to be smaller than the proximal end width WR, the bristles 21 at the distal end portion of the brush portion 2 The density is increased, and it is possible to improve the cleanability of details such as the interdental part and the tooth neck part, and it is easy to apply the tip part of the brush part 2 to the tooth neck part.

  The bristles 21 are tapered, and the ratio of the length from the tip of the bristles 21 to the total length L of the bristles 21 is 10% to 20% of the cross-sectional area of the base end, and 25% at the 15% position. The cross-sectional area at the position is set to 20 to 40% of the cross-sectional area of the base end part, and the cross-sectional area at the 50% position is set to 60 to 80% of the cross-sectional area of the base end part. While improving the insertion property to a clearance part and improving cleaning property, the bending of the bristles 21 by brushing can be prevented, and also the durability of the brush part 2 can be improved.

  As shown in FIG. 5B, the first-side projection surface arc portion 23 a is arranged on the first side (base end side in the longitudinal direction of the handle 10) 23 in the side view of the bristles 21 in order from the distal end side of the bristles 21. The projecting surface side straight portion 23b, the first base end side projecting surface arc portion 23c, the second base end side projecting surface arc portion 23d, and the concave arc portion 23e are formed in a smooth manner. The projecting arc portions 23a, 23c, and 23d are arcs having a center on the second side (the distal end side in the longitudinal direction of the handle 10) 24 side. The concave arc portion 23e is formed of an arc having a center on the side opposite to the second side 24. On the second side 24 in the side view of the bristles 21, an orthogonal linear portion 24 a that is substantially orthogonal to the front surface of the base portion 22 (the standing surface of the bristles 21) is formed over the entire length of the bristles 21. In this way, by configuring the first side 23 and the second side 24 of the bristles 21, it is possible to prevent the occurrence of stress concentration during brushing and to prevent the bristles 21 from being bent due to the stress concentration.

  The radius of the tip-side protruding arc portion 23a is set to 0.05 to 0.25 mm, the length L1 of the bristles 21 in the longitudinal direction is set to 0.1 to 0.25 mm, and the bristles of the protruding-side straight portion 23b are set. The length L2 in the longitudinal direction of 21 is set to 3.5 to 6.0 mm. The radius of the first base-side projecting surface arc portion 23c is set to 5 to 20 mm, the length L3 of the bristles 21 in the longitudinal direction is set to 0.1 to 3.0 mm, and the second base-side projecting surface arc portion The radius of 23d is set to 65 to 120 mm, and the length L4 in the longitudinal direction of the bristles 21 is set to 3.5 to 6.0 mm. The radius of the concave arc portion 23e is set to 0.1 to 0.25 mm, and the length L5 in the longitudinal direction of the bristles 21 is set to 0.1 to 0.25 mm.

  However, if the first side 23 is configured to include at least two projecting arc portions having a center on the second side 24 side, the bending of the bristles 21 during brushing can be prevented. For example, instead of the projecting surface side straight portion 23b, a projecting surface arc portion is provided, and the first side 23 is constituted by four projecting surface arc portions, or the base end side projecting surface arc portions 23c and 23d are formed as a single arc. The first side 23 can also be constituted by two projecting arc portions and a projecting side straight portion 23b.

  The cross-sectional shape orthogonal to the length direction of the bristles 21 can be any shape such as a circle, a semicircle, a semi-oval, an ellipse, a semi-elliptic, a triangle, a quadrangle such as a trapezoid, a rectangle, or a square, and a polygon shape that is a pentagon or more It can be configured in the shape of In particular, a flat surface 21a substantially perpendicular to the length direction is formed on the second side 24 of the bristles 24 (the tip end side in the length direction of the handle 10), and a half like the bristles 21 shown in FIG. An ellipse, a semi-elliptical shape such as the bristles 21A shown in FIG. 7B, a triangle such as the bristles 21B shown in FIG. 7C, and an equal leg such as the bristles 21C shown in FIG. Bristles having a cross-sectional shape such as a trapezoid can also be employed. When the flat surface 21a is provided in this way, one molding surface of the mold for molding the bristles 21 can be constituted by the flat surface 21a, and the releasability when the mold is released from the bristles 21 can be greatly improved. Moreover, since both sides of the flat surface 21a become corners, plaque and the like adhering to the tooth surface can be scraped off at the corners, and the cleanability can be improved.

  As shown in FIG. 6, it is preferable that the distal end portion of the bristles 21 is formed in a partial spherical shape having a radius R of 0.1 mm or more because it can prevent the gums from being damaged. However, the distal end shape of the bristles 21 can be arbitrarily set, and can be configured to be sharp or hemispherical or spherical.

  The bristle 21 has a bristle length of preferably 7.5 mm to 12 mm, and more preferably 8.5 mm to 11 mm in consideration of cleaning properties and durability.

  The arrangement of the bristles 21 with respect to the base portion 22 can be arbitrarily set in the column direction (longitudinal direction of the handle 10) as long as it is arranged in series in the row direction (width direction of the handle 10). Further, the bristles 21 are configured such that the flat surfaces 21a of all the bristles 21 are arranged only on the distal end side in the longitudinal direction of the handle 10, as shown in FIG. 2 (a), or only on the proximal end side. It can comprise so that it may be arrange | positioned, or it can provide in combination arbitrarily in the front end side or the base end side for every row of the bristles 21. In addition, as the bristles, a plurality of types of bristles 21 having different cross-sectional shapes, cross-sectional dimensions, hair lengths, and the like can be provided on the base portion 22.

  In the toothbrush 1, after the handle 10 of the toothbrush 1 is injection-molded, the handle 10 is set in a mold for forming the brush member 20, and the molten resin material constituting the brush member 20 is injected from the gate G. Thus, the toothbrush 1 is manufactured by insert-molding the brush member 20 having the plurality of bristles 21 and the base portion 22 in the head portion 11 of the handle 10. The gate G can be provided at any position corresponding to the brush member 20, but is provided at the center of the rear surface of the base rear portion 22b or at the center of the rear surface of the elastic deformation promoting portion 22d. It is preferable.

  The head portion 11 of the handle 10 is formed with a communication hole 11f communicating with the front and rear surfaces of the head portion 11, and the base portion 22 of the brush member 20 formed by insert molding is provided on the front side of the head portion 11. The base front part 22a, the base rear part 22b on the rear surface side of the head part 11, and the connecting part 22c for connecting the base front part 22a and the base rear part 22b through the communication hole 11f are formed. Thus, the bonding strength of the brush member 20 to the handle 10 can be easily improved. Moreover, since the brush member 20 is couple | bonded with the handle | pattern 10 by such mechanical coupling | bonding, what has no compatibility as a material which comprises the handle | pattern 10 and the brush member 20 is employable. Therefore, the degree of freedom of selection of the material constituting the handle 10 and the brush member 20 is increased, and both can be constituted by the optimum material corresponding to the required characteristics of the handle 10 and the brush member 20.

  As in the toothbrush 1 </ b> A shown in FIG. 8, the groove portion 30 is formed at the tip of the frame portion 11 a, and the resin material constituting the brush member 20 is filled in the groove portion 30 when the brush member 20 is molded, It is also possible to form an impact absorbing portion 31 that absorbs an impact at the time of contact. That is, at the time of brushing, the tip of the head part 11 may hit the teeth. In this toothbrush 1 </ b> A, the shock absorbing part 31 made of a resin material constituting the brush member 20 that is softer than the handle 10 has the tip of the head part 11. It is possible to effectively prevent a large impact force from acting on the teeth by placing the impact absorbing portion 31 on the teeth.

  Further, like the brush member 20B of the toothbrush 1B shown in FIG. 9, a brush portion 2B composed of a plurality of bristles 21 protruding rearward is formed on the rear surface of the base rear portion 22b, like the base front portion 22a. It is also possible.

  In the present embodiment, the case where the present invention is applied to a manual toothbrush that grips and brushes the handle 10 by hand has been described. However, a replacement brush for an electric toothbrush, a brush for gingival massage, a face washing brush, and a face massage It is also possible to apply the present invention to brush tools such as brushes and body brushes.

Next, the performance test of the toothbrush 1 will be described.
As toothbrushes, toothbrushes of Examples 1 to 3 and Comparative Examples 1 to 4 having the following configurations were manufactured.

Example 1
1 to 6, the brush member 20 is made of polyethylene resin, the bristle 21 has a bristle length L set to 10.5 mm, and a tip-side projecting arc of the first side 23 in a side view. The radius of the portion 23a is set to 0.1 mm, the length L1 is set to 0.09 mm, the length L2 of the projecting surface side straight portion 23b is set to 5.44 mm, and the radius of the first base end side projecting surface arc portion 23c is set. Is set to 10 mm, the length L3 is set to 0.33 mm, the radius of the second proximal-side protruding arc portion 23d is set to 108 mm, the length L4 is set to 4.49 mm, and the radius of the concave arc portion 23e is set to 0.4 mm. The length L5 was set to 0.15 mm. The cross-sectional area of the base end portion of the bristles 21 was set to 0.36 mm ² . On the second side 24 in a side view, a toothbrush composed of orthogonal straight portions 24 a orthogonal to the longitudinal direction of the handle 10 was manufactured.

(Example 2)
Instead of the bristles 21, a toothbrush having the same configuration as that of Example 1 was manufactured except that the bristles 25A shown in FIGS. 10 (a) and 10 (b) were employed. For the bristles 25A, the bristle length LA is set to 8.5 mm, the radius of the tip side protruding arc portion 23Aa on the first side 23A is set to 0.1 mm, the length LA1 is set to 0.1 mm, and the protruding surface side straight portion The length LA2 of 23Ab is set to 3.35 mm, the radius of the first base-side protruding arc portion 23Ac is set to 10 mm, the length LA3 is set to 0.62 mm, and the length of the second base-side protruding arc portion 23Ad is set. The radius was set to 100 mm, the length LA4 was set to 4.29 mm, the radius of the concave arc portion 23e was set to 0.4 mm, and the length LA5 was set to 0.15 mm. The second side 24A was constituted by an orthogonal straight part 24Aa orthogonal to the longitudinal direction of the handle 10, and the cross-sectional shape and the cross-sectional area of the base end were the same as in Example 1.

Example 3
Instead of the bristles 21, a toothbrush having the same configuration as in Example 1 was manufactured except that bristles 25B shown in FIGS. 11 (a) and 11 (b) were employed. For the bristles 25B, the bristle length LB is set to 10.5 mm, the radius of the tip-side protruding arc portion 23Ba on the first side 23B is set to 0.1 mm, the length LB1 is set to 0.09 mm, and the protruding-surface-side straight portion The length LB2 of 23Bb is set to 5.66 mm, the radius of the proximal-side protruding arc portion 23Bc is set to 100 mm, the length LB3 is set to 4.60 mm, and the radius of the concave arc portion 23Be is set to 0.4 mm. L5 was set to 0.15 mm. The second side 24 </ b> B is configured by an orthogonal straight portion 24 </ b> Ba orthogonal to the longitudinal direction of the handle 10, and the cross-sectional shape and the cross-sectional area of the base end are configured in the same manner as in the first embodiment.

(Comparative Example 1)
Instead of the bristles 21, a toothbrush having the same configuration as that of Example 1 was manufactured except that bristles 25C shown in FIGS. 12 (a) and 12 (b) were employed. For the bristles 25C, the bristle length LC is set to 8.0 mm, the radius of the tip-side protruding arc portion 23Ca of the first side 23C is set to 0.1 mm, the length LC1 is set to 0.10 mm, and the length LC2 is 7 A 90 mm straight portion 23Cb was formed. The second side 24C is configured by an orthogonal linear portion 24Ca orthogonal to the longitudinal direction of the handle 10, the cross-sectional shape is configured in the same manner as in Example 1, and the cross-sectional area of the base end portion of the bristles 25C is set to 0.28 mm ² . did.

(Comparative Example 2)
A toothbrush having the same configuration as in Example 1 was produced except that the bristles 25D shown in Fig. 13 (a (b)) were adopted instead of the bristles 21. The bristles 25D had a bristle length LD set to 10.5 mm. The radius of the tip side protruding arc portion 23Da on the first side 23D is set to 0.1 mm, the length LD1 is set to 0.10 mm, and the straight portion 23Db having the length LD2 of 10.40 mm is formed. The cross section is configured in the same manner as in Example 1 and the cross-sectional area of the base end of the bristles 25D is set to 0.28 mm ² .

(Comparative Example 3)
Instead of the bristles 21, a toothbrush having the same configuration as in Example 1 was manufactured except that bristles 25E shown in FIG. 14 were adopted. The bristles 25E have a hair length LE of 9.8 mm, a hemispherical portion 23Ea with a radius of 0.1 mm formed at the tip, and a first truncated cone portion 23Eb with a length LE1 of 1.9 mm formed at the top. A second truncated cone part 23Ec having a length LE2 of 3.0 mm was formed in the part, and a cylindrical part 23Ed having a length LE3 of 4.8 mm was formed in the lower part. The cross-sectional shape was circular, and the cross-sectional area of the base end of the bristles 25E was set to 0.57 mm ² .

(Comparative Example 4)
A flocking hole having a diameter of 1.5 mm is formed on the flocking table in the same arrangement as the bristles 21 in FIG. 2 (a), and instead of the bristles 21 with respect to the flocking holes, as shown in FIG. So that the projecting length LF is 12 mm, the cross section of the base end of the projecting portion from the flocking table is a circle having a diameter of 0.16 mm, the cross-sectional area of the base end is 0.02 mm ² , and the side view is A toothbrush in which 28 sharp filaments 25F made of polybutylene terephthalate having two straight portions were implanted in each flock hole was produced.

<Cleanability test>
A brushing simulator designed to brush the teeth of a fixed jaw model (D15-500H, Nissin) while keeping the brushing pressure and moving speed of the toothbrush constant was used. As an alternative to plaque, a colored powder of spray occlude (Pascal) for occlusion check was applied to the jaw model. The brushing pressure was set to 200 g, and the first molar was brushed with a stroke in the longitudinal direction for 3 seconds at a stroke width of 20 mm. Thereafter, the subject teeth were photographed and image analysis was performed. Evaluation of the interdental cleaning property was performed by calculating the removal rate of the colored powder as follows. In Table 1, the case where the interdental plaque removal rate (%) is 50% or more is represented by “◯”, and the case where it is less than 50% is represented by “x”.

Colored powder removal rate (%) = [{(Evaluation site area) − (Colored powder remaining area)} / (Evaluation site area)] × 100

<Durability test>
The toothbrush was immersed in warm water at 37 ° C., and was reciprocated 5,000 times with a load of 300 g. (A) The width of the brush portion in the short axis direction of the toothbrush in the initial state (the tip of the bristles being planted Width WA, (B) The width WB of the brush portion in the short axis direction of the toothbrush with the bristles open after 5,000 reciprocations, and the durability index calculated by the following formula (the lower the index, the more durable In Table 1, when the durability index is 100 to 140%, it is represented by “◯”, and when it exceeds 140%, it is represented by “x”.

Durability index (%) = [WB / WA] × 100

<Sensory test 1>
Each toothbrush was subjected to a tip endurance test by one use by 10 subjects. Each subject was evaluated for the presence or absence of bending at the bristle tip, and the durability of the bending after one use was determined according to the following criteria.

(Criteria)
○: 8 or more people are not bent Δ: 5 to 8 people are not bent ×: Less than 5 people

  From Table 1, it can be seen that the cleaning performance of the interdental portion, the durability of the brush portion, and the bending of the bristles after use vary greatly depending on the shape of the bristles in a side view. When the first side is configured with two or more projecting arc portions as in Examples 1 to 3, and the second side is configured with an orthogonal straight portion orthogonal to the longitudinal direction of the handle (brush portion), Comparative Examples 1 to As shown in FIG. 4, it can be seen that better performance can be obtained as compared with the case where the first side is constituted by a straight portion. In particular, when the ratio SA / SB of the cross-sectional area SA and the base end area SB at the position where the length from the tip is 50% relative to the total length of the bristles is less than 60%, Comparative Examples 1 and 2 The bristles are bent as shown in FIG. Further, as in Comparative Examples 3 and 4, even when the ratio SA / SB at the 50% position is 60% or more, when the ratio SA / SB at the 25% position exceeds 50%, the ratio at the 15% position is Since the ratio SA / SB exceeds 20% and the tip of the bristles becomes thick, there is a problem that the durability of the bristles is reduced or the interdental part is less cleanable. I understand.

<Sensory test 2>
About each toothbrush, the sensory test of the massage feeling, the presence or absence of a stimulus, a brushing feeling, and the ease of applying to a tooth neck part was performed by 10 test subjects, and each was evaluated according to the following criteria.

(Massage feeling)
◎: Can be felt very much ○: Can be felt ×: Cannot be felt at all

(A feeling of brushing, ease of application to the tooth neck)
◎: Very good ○: Good ×: Bad

(Comprehensive evaluation)
In the evaluation of “massage feeling” and “brushing feeling, ease of application to the tooth neck”, the ratios of the numbers of “◎” and “◯” were respectively obtained and comprehensively evaluated.
◎: 80% or more ○: 50% or more ×: Less than 50%

  From Table 2, when the ratio WT / WR (see FIG. 4) of the front end width WT and the base end width WR of the brush portion is smaller than that of Comparative Examples 3 and 4 as in Examples 1 to 3, the brush portion It can be seen that the density of bristles at the tip increases, and the cleaning feeling, ease of application to the tooth neck, and massage feeling are improved.

  Next, the analysis result of the stress distribution when an external force is applied to one bristles will be described.

  As shown in FIG. 5 and FIG. 17, the bristles of Example 1 in which three projecting arc portions 23 a, 23 b, 23 c are formed on the first side 23, and the orthogonal straight portions 24 a are formed on the second side 24. 25, and bristles 25B of Example 3 in which two projecting surface arc portions 23Bb and 23Bc are formed on the first side 23B and an orthogonal linear portion 24Ba is formed on the second side 24B, as shown in FIGS. As shown in FIGS. 12 and 19, the bristles 25C of Comparative Example 1 in which the straight portion 23Cb is formed on the first side 23C and the orthogonal straight portion 24Ca is formed on the second side 24C were used. Moreover, as shown in FIG. 20, the bristles of the comparative example 5 which comprised the 1st side and the 2nd side with the straight line were used.

  And using Solid Works Simulation (made by Solid Works), about the bristles of Examples 1 and 3 and Comparative Examples 1 and 5, the base end S of the bristles is fixed, and 2 mm from the tip of the second side 24 of the bristles. 16A, as shown in FIG. 16A, the stress distribution when a pressing force F1 of 0.01 N is applied, and the tensile force F2 of 0.01 N as shown in FIG. We analyzed the stress distribution when the FIGS. 17A to 20A show analysis results when the pressing force F1 is applied as shown in FIG. 16A, and FIGS. 17B to 20B are diagrams. The analysis result when the tensile force F2 is applied as shown in FIG. 16 to 20, the background of the bristles is depicted with a mesh so that the outer shape of the bristles can be easily identified.

  From FIG. 17 to FIG. 20, when the pressing force F <b> 1 is applied and when the tensile force F <b> 2 is applied, the first side has three projecting arc portions or 2 as in the first and third embodiments. The bristles configured with two projecting arc portions have higher stresses at two locations along the length of the bristles, whereas the first side has two linear portions or The bristles composed of one straight part have higher stress at one point in the middle of the length of the bristles, and the stress is more dispersed in Examples 1 and 3 than in Comparative Examples 1 and 5. It can be seen that the bristles are difficult to break.

  The embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and it goes without saying that the configuration can be changed without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Toothbrush 2 Brush part 10 Handle 11 Head part 11a Frame part 11b Vertical beam 11c Horizontal beam 11d Front part fixing recessed part 11e Rear part fixing recessed part 11f Communication hole 12 Grip part 13 Neck part 13a Connecting part 13b Deformation promotion recessed part 20 Brush member 21 bristles 21a flat surface 22 base portion 22a base front portion 22b base rear portion 22c connecting portion 22d elastic deformation promoting portion 23 first side 23a tip side protruding arc portion 23b protruding surface side straight portion 23c first base end side protrusion Surface arc part 23d Second base end side projecting arc part 23e Concave arc part 24 Second side 24a Orthogonal straight part 21A Bristles 21B Bristles 21C Bristles 1A Toothbrush 30 Groove 31 Shock absorber 1B Toothbrush 2B Brush part 20B Brush member 25A Bristles 23A First side 23Aa Front end side projecting arc portion 23Ab Projection side linear portion 23Ac Base end side projecting arc portion 23Ad Base end side projection surface circle Part 24A Second side 24Aa Orthogonal straight part 25B Bristles 23B First side 23Ba Tip side projection arc part 23Bb Projection side linear part 23Bc Base end side projection arc part 23Be Concave arc part 24B Second side 24Ba Orthogonal straight part 25C Bristle 23C First side 23Ca Tip side protruding arc portion 23Cb Linear portion 24C Second side 24Ca Orthogonal straight portion 25D Bristles 23D First side 23Da Tip side protruding arc portion 23Db Straight portion 24D Second side 24Da Orthogonal straight portion 24a Orthogonal straight portion 25E Bristles 23Ea Hemisphere portion 23Eb Frustum portion 23Ec Frustum portion 23Ed Column portion 25F Filament

Claims (11)

A brush member in which a plurality of bristles are integrally formed on a base part, a brush tool integrally provided by insert molding at the tip of a handle,
A head is provided at the tip of the handle,
A communication hole for communicating the front and rear surfaces of the head portion is provided,
The base part is connected to the front part of the base part on the front side of the head part, the rear part of the base part on the rear surface side of the head part, and the base part and the rear part of the base part through the communication hole. And provided a part
A brush tool characterized by that.   On the first side of the bristles, at least two projecting arc portions having a center on the side of the second side are formed on the first side, and substantially perpendicular to the front surface of the base over the entire length of the bristles on the second side. The brush tool according to claim 1, wherein an orthogonal straight portion is formed.   As the protruding arc portion, a distal-side protruding arc portion is formed at the first-side distal end portion, and a proximal-side protruding arc portion is formed at the proximal-side portion of the first side. The brush device according to claim 2, wherein a linear projecting surface side straight portion connected to both projecting arc portions is formed at a tip side portion on the side.   The brush tool according to any one of claims 1 to 3, wherein a concave circular arc portion connected to the front surface of the base is formed at a base end portion on the first side in a side view of the bristles.   The bristles are tapered, and the ratio of the length from the tip of the bristles to the total length L of the bristles is such that the cross-sectional area at the 15% position is 10-20% of the cross-sectional area of the base end, and 25% The cross-sectional area at the position is set to 20 to 40% of the cross-sectional area of the base end portion, and the cross-sectional area at the 50% position is set to 60 to 80% of the cross-sectional area of the base end portion. The brush tool described.   The brush tool according to any one of claims 1 to 5, wherein a flat surface substantially orthogonal to the longitudinal direction of the handle is formed on the second side of the bristles.   The flat surface of the plurality of bristles provided on the base part is only on the front end side or the base end side in the longitudinal direction of the handle, or on the front end side or the base end side for each row of bristles in the base part. The brush tool according to claim 6 provided.   The brush tool according to any one of claims 1 to 7, wherein a tip of the bristles is formed in a partial spherical shape having a radius of 0.1 mm or more.   The brush tool according to any one of claims 1 to 8, wherein the front part of the base protrudes forward from the head part within a range of 0.5 mm to 1.0 mm.   The brush tool of any one of Claims 1-9 which set the front-end | tip width | variety of the brush part which consists of these multiple bristles to 75% or more and 95% or less of the base end width.   The brush tool according to claim 1, wherein the brush member is made of an elastomer.