JP4854750B2 - Brush manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a brush, and more particularly to a method for manufacturing a brush suitable for manufacturing a toothbrush.

As a method of manufacturing a brush, conventionally, a hair bundle is taken out from a set of hairs cut to a predetermined length using a sleeve, and the hair bundle stored in the sleeve is provided in a mold or the like. A method of inserting the hair bundle into the hair and fixing the hair bundle with resin or the like has been known.
However, due to twisting of the hair, etc., the tip of the hair bundle spreads, the hair breaks during the manufacturing process, or the tips of the hair bundle are not aligned and the desired performance and appearance There was a problem that could not be obtained.
For this reason, there is a method in which a necessary number of long hairs wound on a reel or the like are unwound and bundled, inserted into the insertion port of a mold or the like while being aligned, and cut to a required length. Currently, it is generally adopted.

  However, in this method, it is necessary to provide a large number of reels in the production line in order to cover the necessary number of hair bundles. In addition to requiring very large equipment, it is also necessary to recover when trouble occurs. There is a lot of time and material loss, which causes a decrease in productivity and an increase in cost. In addition, since it takes a lot of manpower, time, and expense to change the type of hair to be used and the flocking pattern, etc., it is possible to produce a wide variety of products with a single facility or to change models quickly. Not suitable for production.

A conventional brush manufacturing method comprising a step of inserting a sleeve into a set of bristle cut to a predetermined length and introducing the sleeve into the sleeve, and then feeding and planting the bristle introduced into the sleeve As a technique, for example, a technique described in Patent Document 1 below is known.
According to this technique, a hair bundle is taken out from a set of hairs using a sleeve, and the hair bundle stored in the sleeve is inserted into a hole provided in a mold.

By the way, in this technique, the bristle bundle introduced into the sleeve is inserted into the mold as it is, one end of the bristle bundle is heated and melted to form a continuous base, and then the molding material is formed. Since the bristle bundle is fixed by filling, the orientation of the bristle bundle is aligned and aligned in each step of introducing the bristle into the sleeve, forming the base by heating and melting, and filling the molding material. There was a problem that the state was greatly disturbed.
Further, in this technique, the density of the hair bundle inserted into the mold hole cannot be increased, so that when the resin is filled in the cavity of the molding mold, the density of the hair bundle is reduced. There was a problem that the resin leaked out.

  On the other hand, in Patent Document 2 below, a sleeve is inserted into a bristle supply body, a bristle bundle is taken out, the bristle in the sleeve is moved to a vise, and then the head (base member) of the brush body is formed from the vice. Also disclosed is a method for manufacturing a brush in which a hair bundle is inserted into a plurality of holes.

Japanese National Patent Publication No. 9-510642 Japanese Patent No. 3226276

However, in this technique, the orientation state and the alignment state of the hair bundle in the sleeve become insufficient, and only a part of the hair bundle is gripped by the vice, so the following problems 1 to 4 occur. there were.
1. When transferring from the sleeve to the vice, the hair bundle is disturbed.
2. Since only a part of the hair bundle is gripped, both ends of the hair bundle except for the grip portion are opened.
3. The hair bundle is disturbed in the process of shaping both ends of the hair bundle with the die.
4). When inserting the hair bundle into the hole provided in the base member, the hair is broken or the hair bundle is twisted, and the insertion itself is difficult. Become.
For this reason, in the obtained brush, the orientation state and the alignment state of the hair bundle for flocking do not satisfy sufficient quality. Also, with this technique, it is difficult to form the tip shape of the hair bundle.

Accordingly, an object of the present invention is to provide a method of manufacturing a brush that is excellent in the orientation of the hair bundle, and that can produce a brush in which the hair is neatly aligned.
Here, excellent orientation of the hair bundle means that the individual hairs constituting the hair bundle extend in the length direction without being twisted or bent and are neatly bundled as a bundle. The state in which the hairs are neatly aligned means that the tips of the individual hairs are in a predetermined alignment form so that the tips of the hair bundles have a desired shape, together with the orientation of the hair bundles. It means that it is neatly arranged.

  The inventors set the ratio (As / Ai) between the cross-sectional area As orthogonal to the axial direction of the sleeve and the cross-sectional area Ai orthogonal to the axial direction of the flock hole or the insertion portion to a specific range, and within the sleeve. By setting the density of the hair to be introduced and the density of the hair to be inserted into the flock hole of the flocking base or the insertion part of the mold within a predetermined range, the hair is neatly aligned and the orientation of the hair bundle is improved. It has been found that an excellent brush can be manufactured stably.

  The present invention has been made on the basis of the above knowledge, and after introducing the hair cut to a predetermined length into the sleeve, the introduced hair is delivered from the inside of the sleeve and the flocked hole of the flocked base portion Or a brush manufacturing method comprising a step of inserting into a mold insertion portion, wherein the cross-sectional area As is perpendicular to the axial direction of the sleeve and the cross-sectional area Ai is perpendicular to the axial direction of the flocked hole or the insertion portion. The ratio (As / Ai) is 1.02 to 1.3 and the hair is introduced into the sleeve at a hair density of 47 to 75%. And a method for manufacturing a brush that is inserted into the flock hole or the insertion portion at a hair density of 60 to 80%.

  According to the present invention, it is possible to manufacture a brush in which the hair bundle is excellent in orientation and the hair is neatly aligned.

It is a figure which shows typically one form of the sleeve used for the manufacturing method of the brush of this invention, (a) is a half sectional view, (b) is a principal part expanded sectional view of the A part of (a). . It is a figure which shows typically one form of the press pin used for the manufacturing method of the brush of this invention, (a) is a side view, (b) is a front view. It is principal part sectional drawing which shows typically the state which extrudes the hair introduced in the sleeve with an extrusion pin, and is inserted in the flock hole. It is the figure which expanded the principal part of FIG. It is a figure which shows typically one form of the apparatus used for the manufacturing method of the brush of this invention. It is a figure which shows the state which has inserted the sleeve in the collection of hair, and has introduced the hair, (a) is a figure which shows the state before inserting a sleeve in hair, (b) is a figure of a sleeve The figure which shows the state which inserted the nozzle part in the hair, (c) is a figure which shows the state which pulled out the sleeve from the hair.

  Hereinafter, the present invention will be described as a preferred embodiment based on an embodiment applied to manufacture of a toothbrush with reference to the drawings.

  First, a sleeve is inserted into a set in which a large number of hairs cut to a predetermined length are vertically aligned, and the use is performed at a predetermined hair density (hereinafter also referred to as sleeve internal hair density) in the sleeve. Introduce hair.

The collection density of the hair can be appropriately set according to the thickness of the hair, the material of the hair, and the length of the hair, but is 50 to 75% from the viewpoint of easily separating the hair. It is preferably 55 to 70%. Here, the accumulation density of the hair is the ratio (percentage) of the total cross-sectional area of the accumulated hair per unit area.
When the hair density is within the above range, it becomes easier to control the hair density within the sleeve within the sleeve when the hair is inserted into the sleeve, and align with the orientation of the hair bundle. The state can be improved. If the collection density is too low, the number of hairs inserted into the sleeve becomes unstable every time it is taken out, so if the number of hairs is low and the hair density in the sleeve is reduced, a part of the hair bundle in the sleeve Problems such as galling are likely to occur. If the accumulation density is too high, when the sleeve is inserted, a part of the hair of the hair set is pushed in, for example, disturbs the alignment state of the hair in the set and is inserted into the sleeve. This tends to deteriorate the alignment of the hair bundles. Further, the hair density in the sleeve may become too high, and in this case, it is impossible to realign the hair bundle in the sleeve. In order to change the density of the hair, use means such as increasing or decreasing the force applied to the hair collection from the radial direction of the hair or increasing or decreasing the volume of the container for storing the hair collection. Can do.

For the bristles, the usual materials and forms conventionally used for bristles for toothbrushes can be used without particular limitation.
Examples of the material for the hair include polyamide such as nylon, and polyester such as polybutylene terephthalate and polytrimethylene terephthalate.
The length of the hair is preferably 5 to 15 mm, more preferably 8 to 13 mm. The thickness of the hair 13 is preferably 5 to 10 mil (127 to 254 μm), more preferably 7 to 9 mil (178 to 229 μm).

  It is preferable to align the hair so that the length direction of the hair is perpendicular to a substantially horizontal alignment surface.

  As shown in FIG. 1, it is preferable to use a sleeve having a nozzle portion 21 inserted into the collection of hairs and a hair introduction hole 22 through which the hairs are introduced vertically. . The upper portion of the introduction hole 22 is expanded in diameter so that an extrusion pin 61 described later can be easily inserted.

The cross-sectional area (As) perpendicular to the axial direction of the introduction hole in the sleeve 2 is a ratio of the cross-sectional area perpendicular to the axial direction of the flock hole to be described later (Ai: flocked hole) When the taper is provided at the insertion opening, the ratio (As / Ai) with respect to the cross-sectional area of the straight portion excluding that portion is set to 1.02 to 1.3. In particular, it is preferable to set to 1.05 to 1.2.
If the ratio (As / Ai) is too small, it becomes difficult to keep the hair density in the flocked hole or the insertion part within the optimum range, and the flocked hole is in a state where the orientation and alignment of the hair in the sleeve are worse. Or a hair bundle may be inserted in an insertion part. In addition, when the hair density at the flock hole or the insertion portion cannot be increased to the optimum range, the step of fixing the hair by heating and melting or resin filling one end of the hair bundle In this case, the orientation state and the alignment state are further disturbed, and resin leakage from the flock holes or the insertion portion occurs.
If the ratio (As / Ai) is too large, the hair density in the flock holes or the insertion portion tends to be excessively high, and the generated stress becomes excessive, so that the tips of the hair bundles are opened. The condition gets worse. Moreover, insertion mistakes such as disturbing the orientation state due to relative displacement or twisting of each hair during insertion, or buckling and breaking of the hair are caused.

  When the nozzle portion 21 is inserted into a set of hairs and the hair is introduced into the introduction hole 22 and then the sleeve is pulled up to separate the hair, the hair around the nozzle portion 21 is pulled up and pulled up. It is preferable to have a tapered shape as a whole so that it can be suppressed. This angle θ1 is preferably 0.5 to 5 °. Moreover, it is preferable that the wall thickness t1 of the nozzle part 21 is 0.1-1 mm from the point which makes it easy to insert in the aggregate | assembly of hair. The length L1 of the nozzle portion 21 can be set as appropriate according to the length of the hair, but from the viewpoint of ensuring the rigidity and durability of the nozzle portion, the difficulty in creating the nozzle portion, and the cost. It is preferable that it is 100 to 150% of the hair length.

  The nozzle portion 21 has a tapered portion 21a that further tapers at the tip portion. The wall thickness t2 at the tip of the tapered portion 21a is preferably thinner than the diameter of one hair. Thus, by making the thickness of the tip of the taper portion 21a thinner than the diameter of one hair, the tip of the taper portion 21a straddles the three hairs (the hair 1 within the thickness). The nozzle portion 21 is smoothly inserted between the hairs. The thickness t2 of the tip of the tapered portion 21a is preferably 0.05 to 0.3 mm. The tip of the taper portion 21a may be rounded. In addition, the angle θ2 of the tapered portion 21a is 5 to 45 degrees from the viewpoint of ensuring the rigidity and durability of the nozzle section, the difficulty of manufacturing the nozzle section, reducing the cost, and facilitating insertion into a set of hairs. Preferably there is.

  In the sleeve 2, the length L3 of the straight portion of the introduction hole 22 (the portion having a constant cross section perpendicular to the length direction excluding the diameter-enlarged portion) is 110 to 300% of the length of the hair. preferable. If the straight portion is too short, when the push pin 60 is retracted in the sleeve 2, a part of the tip portion 60a is applied to the diameter-enlarged portion of the introduction hole 22 so that the insertion becomes unstable or the length of the hair is long. There is a case where it becomes impossible to cope with the change, and if the straight portion is too long, if the L4 of the extrusion pin 60 becomes long, it becomes easy to bend and there is a possibility that it contacts the introduction hole 22 of the sleeve 2.

  The sleeve 2 is preferably made of metal such as carbon tool steel, alloy tool steel, and high speed steel from the viewpoint of processing accuracy, durability, rigidity, cost, and the like.

  Further, the outer surface of the nozzle portion 21 is subjected to electroless plating, surface treatment with Teflon (registered trademark) resin, or the like from the viewpoint of suppressing resistance when the nozzle portion 21 is inserted into a set of hairs. It is preferable to finish the surface by lubrication.

  The hair density in the sleeve is 47 to 75%, preferably 55 to 70%, more preferably 60 to 65%. If the hair density in the sleeve is too low, the alignment state when it is taken out from the collection of hairs may not be maintained in the sleeve, and if it is too high, the extrusion resistance increases, and the hair is between the extrusion pin and the introduction hole. May be bitten, or the resistance of displacement between the hairs will increase, and when the tips of the hairs are aligned in a predetermined alignment form, the shape may not correspond to the alignment form. Here, the hair density in the sleeve means (total cross-sectional area perpendicular to the length direction of the hair to be inserted) / (cross-sectional area perpendicular to the axial direction in the linear portion of the sleeve). In order to change the hair density in the sleeve, means such as increasing / decreasing the accumulation density in the collection of hairs, changing the area and shape of the front end opening of the sleeve, and the like can be used.

  Next, the bristle introduced into the sleeve at the bristle hair density is delivered from the sleeve. For the delivery of the hair from the sleeve, an extrusion pin 60 that can be inserted into the sleeve as shown in FIG. 2 is used.

  The extruding pin 60 has a portion of a predetermined length (L4) from the tip thereof so that the bristles introduced into the sleeve can all be fed from the outlet of the introduction hole. It has a cross-sectional form corresponding to a cross section orthogonal to the length direction. It is preferable that the predetermined length portion is provided in a predetermined clearance narrower than the thickness of the bristle between the inner surface of the introduction portion. This clearance is preferably 0.02 to 0.15 mm. If this clearance is too narrow, the extrusion pin may come into contact with the introduction hole, and if it is too wide, the bristle may be caught between the extrusion pin and the introduction hole.

  When the front end portion 60a of the push pin 60 is arranged in a predetermined alignment form, it is preferable to have a shape corresponding to the alignment form. For example, as shown in FIG. 3 and FIG. 4, when the tip of the insertion hole 80 of the hair holding jig 8 has a curved shape, and the tip of the hair corresponds to this and is arranged in a curved shape. 2, the tip 60a of the extrusion pin 60 is provided with a step on the surface orthogonal to the feeding direction according to the curvature thereof, as shown in FIG. 2, or is provided with a curved surface so as to correspond to the form. It is preferable to make the hair 10 in the shape corresponding to the final curved shape in advance. When the tip of the push pin is provided in a curved shape, it is preferable to provide a surface perpendicular to the feed direction with a predetermined width inside from the outer edge of the tip of the push pin.

  And the said hair is inserted in the flock hole of the said flock base by the predetermined hair density (the hair density in a flock hole: Hereinafter, it is also only called the flock density).

  The flocking density is preferably 60 to 80%, more preferably 65 to 75, and still more preferably 70 to 75. Here, the flocking density refers to (total cross-sectional area orthogonal to the length direction of the inserted hair) / (cross-sectional area orthogonal to the axial direction of the flock hole). By setting the flocking density within the above range, the orientation state and the alignment state of the hair bundle for a brush can be further improved. If the flocking density is too high, the hair density in the flocking hole or the insertion part tends to be excessively high, and the generated stress becomes excessive, so that the orientation state such as the tip of the hair bundle opening becomes worse. . In addition, the insertion hairs are likely to be misaligned when they are relatively displaced or twisted at the time of insertion, or the insertion hair is buckled and bent. If the flocking density is too low, in one step of fixing the bristles by heating and melting or resin filling one end of the bristles, the orientation and alignment may be further disturbed, The resin leaks easily. In order to change the hair density, means such as changing the sleeve internal hair density or changing the area ratio (As / Ai) can be used.

  The cross-sectional area As orthogonal to the axial direction of the flock hole can be appropriately set according to the cross-sectional area As orthogonal to the axial direction of the sleeve. It is preferable to provide a diameter-expanded portion that gradually increases in a tapered shape toward the outside at the insertion port of the flock hole. By providing the taper, the hair bundle can be easily inserted, and at the same time, the alignment state and the orientation state of the hair bundle in the sleeve can be easily maintained after the insertion. Moreover, even when the depth direction of the flock hole or the insertion portion is inclined with respect to the insertion direction of the hair, it can be inserted while maintaining the alignment state and the orientation state. In addition, an auxiliary member having a hole corresponding to a plurality of flocked holes and having a taper on one of them is arranged between the flocked base or the mold and the sleeve without providing a taper at the insertion port, and is used through the auxiliary member. A method of inserting a hair bundle can also be preferably used. The angle θ3 (see FIG. 4) of the enlarged diameter portion is preferably 20 to 120 °.

  As a preferable dimension setting of the flocked base, in consideration of the alignment and orientation of the hair bundle, as shown in FIG. 4, the thickness a2 of the flocked base is 1 mm to 3 mm, and the effective hole length of the flocked hole 12a ( The straight portion a1 is preferably set to 0.5 mm to 2.5 mm. Further, the hole diameter of the insertion hole 80 of the hair bundle holder 8 is basically the same as the hole diameter of the flock hole 12a of the hair implantation base, but the insertion hole 80 is considered in consideration of the insertability of the hair bundle. It is preferable to set the hole diameter larger by about 0.05 mm to 0.2 mm than the hole diameter of the flocked hole 12a.

The method of this embodiment can be performed with the apparatus 1 as shown in FIG. 5, for example.
The device 1 is a device that separates and transfers a predetermined number of hairs from a set of hairs cut to a predetermined length, and moves in the z-axis direction so as to insert a sleeve 2 into the set of hairs. A moving means 3, a supporting means 4 for supporting the sleeve 2 on the bristles, and a hair feeding means 6 for moving the push pin 60 in the hair feeding direction are provided.

  The bristle delivery means 6 includes a vertical movement mechanism 61 that moves the push pin 60 up and down.

  Next, as shown in FIG. 6A, the sleeve 2 is moved above the set of hairs accumulated as described above. Then, as shown in FIG. 6 (b), the sleeve 2 is lowered by the moving means 3 to insert the nozzle portion 21 into the hair 10, and a predetermined number of hairs 10 are placed in the introduction hole 22 of the sleeve 2. Introduce.

  Next, after the hair is introduced into the introduction hole 22, the introduced hair 10 is pulled up together with the sleeve 2 by the moving means 3 as shown in FIG.

  Next, as shown in FIG. 3, the sleeve 2 in which the bristle 10 is introduced is moved above the toothbrush body 11 fixed on the bristle bundle holding jig 8. Then, the push-out pin 60 is lowered by the vertical movement mechanism 61 of the bristle delivery means 6 so that the tip of the hair 10 corresponds to the tip of the bristle bundle insertion hole 80 of the bristle bundle holder 8. While being aligned, the toothbrush main body 11 is inserted into the bristle bundle insertion hole 80 through the flocking hole 12a of the flocking base 12. And the flocking process of one hair bundle is completed.

  After completion of the flocking process for all the flocked holes, the sleeve 2 and the push pin 60 are retracted, and the melting end portion of the hair bundle protruding from the flocked hole 12a is replaced with a predetermined melting means (not shown) such as a laser beam. ) To form a molten mass. Then, the back portion of the flocked portion 12 is formed by a conventional method such as injection molding or coating with an adhesive, and the manufacture of the toothbrush is completed.

  As described above, according to this embodiment, it is possible to manufacture a brush in which the hair bundle is excellent in orientation and the hair is neatly aligned.

Further, according to the present embodiment, since the flocking base portion is positioned and fixed to the hair bundle holder 8 and injection molding is performed, the insertion portion of the hair is formed in the injection mold and direct injection molding is performed. Resin leakage is less likely to occur than when performing.
Further, by using a resin-made flocking base that can be elastically deformed, it is possible to reduce the pressure fluctuation of the hair bundle in the flocked hole due to the fluctuation of the number of hairs to be taken out from the collection of hairs in the sleeve. It is possible to suppress disturbances in the orientation state and the alignment state of the hair bundle.
In addition, even when the number of wires is large, the insertion resistance can be reduced, so that it is possible to suppress breakage of the hair and disorder of the alignment state.

  The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit of the present invention.

  The present invention introduces a plurality of hairs separated in advance corresponding to the hair bundle into the sleeve by an air flow, and then sends the introduced hair from the sleeve to send the flock hole or the hair The present invention can also be applied when inserting into the insertion portion with the predetermined hair density. In this case, it is preferable that the hair is introduced into the sleeve at 47 to 75%, particularly 50 to 60%.

  In the above-described embodiment, the hair is inserted into the insertion hole of the hair bundle holder through the flocking hole of the flocking base, but the insertion target of the hair bundle is not limited thereto. For example, the insertion hole of a jig having a plurality of insertion holes, such as a hair bundle insertion hole provided in a mold constituting the cavity of the flocking portion of the toothbrush, and a plurality of hair bundles oriented in a predetermined direction Etc. can also be the insertion target of the hair bundle.

  The present invention is particularly suitable for the production of toothbrushes as in the above embodiment, but can also be applied to the production of brushes other than toothbrushes, for example, the production of hair brushes, massage brushes, cleaning brushes and other various brushes. .

  Hereinafter, the present invention will be described more specifically with reference to examples.

  As shown in Examples 1 to 8 and Comparative Examples 1 to 12 below, the hair is inserted into the flocked hole, and the end protruding from the flocked hole is melted as follows to form a molten mass, as described below. Then, the melted mass was coated and transplanted by injection molding to obtain a predetermined toothbrush. And the evaluation in that case was performed as follows. The results are shown in Table 1.

[Examples 1-8]
Using the following hair, as shown in Table 1, the ratio (As / Ai) between the cross-sectional area As orthogonal to the axial direction of the sleeve and the cross-sectional area Ai orthogonal to the axial direction of the flocked hole or the insertion portion, The hair density in the sleeve and the hair density in the flock hole were changed, and the hair was implanted into the flock hole below.
<Bristles>
Hair: Nylon, length 13mm, thickness 0.203mm
Hair density: 60%

<Sleeve>
Introduction part: length (L3) 29 mm, cross-sectional shape 0.9 × 2.32 mm, track circle cross-sectional area 1.914 mm ²
Nozzle part: Length (L1) 16mm

<Flocking hole>
Flocked base: polypropylene Flocked hole: depth (straight portion) 1.0 mm, cross-sectional shape 0.8 × 2.2 mm track circle, cross-sectional area 1.623 square millimeters

<Transmission condition>
Cross-sectional shape of the extrusion pin: offset by −20 μm from the cross-sectional shape of the sleeve.
Delivery speed: 100mm / sec

<Condition for melt mass formation>
Carbon dioxide laser output 13w, spot diameter 0.15mm, scanning speed 150mm.

<Injection molding conditions (Filled base back filling)>
Resin temperature: 220 ° C., injection pressure (resin pressure): 300 kg / cm ²

[Twisting of hair bundle after flocking]
The twist of the hair bundle after flocking was evaluated in the following three stages.
○: The hair bundle shape projected in the direction of the hair axis at the tip of the hair bundle that has been flocked can be recognized as being substantially similar to the shape of the flock hole, and the axial direction of the hair is almost aligned.
(Triangle | delta): Although the axial direction of a hair is inclined to the flock hole shape circumferential direction, it can recognize as a flock hole shape and a substantially similar shape.
X: The axial direction of the hair is greatly inclined in the circumferential direction of the flock hole shape, the bristles spread in a petal shape, and the flock hole shape cannot be recognized.

[Alignment of hair bundles after flocking]
The alignment property of the hair bundle after flocking was evaluated in the following three stages.
○: The hair bundle shape projected in the direction of the hair axis at the tip of the hair bundle that has been flocked can be recognized as being substantially similar to the shape of the flock hole, and the axial direction of the hair is almost aligned.
(Triangle | delta): It exists in the range which several of the hair bundles for which it was flocked incline with respect to the hair bundle axial direction, and it does not exceed the width | variety of a base which contacts the adjacent hair bundle.
X: Some or many of the hair bundles planted are inclined with respect to the hair bundle axis direction, and enter the adjacent hair bundle or exceed the width of the base portion.

[Broken hair in the assembly]
The broken hair in the set of hairs was evaluated in the following three stages.
○: Almost no broken hair is mixed in the hair bundle taken out by the sleeve.
(Triangle | delta): If the broken hair is not removed from the collection of regular hair regularly, the broken hair will mix in the bristle bundle taken out with the sleeve.
X: Broken hair is mixed in the hair bundle taken out with the sleeve, and cannot be implanted continuously.

[Flying after flocking]
The raising of the hair after planting was evaluated in the following three stages.
○: The hair bundle shape projected in the direction of the hair axis at the tip of the hair bundle that has been flocked can be recognized as being substantially similar to the shape of the flock hole, and the axial direction of the hair is almost aligned.
(Triangle | delta): Although the axial direction of the hair is inclined in the direction substantially orthogonal to the flock hole shape circumferential direction, it can be recognized that the flock hole shape is substantially similar. Spread is less than 1.2 times the flock hole size.
X: The axial direction of the hair is greatly inclined in a direction substantially perpendicular to the circumferential direction of the flock hole shape, and the spread exceeds 1.2 times the flock hole size, or the flock hole shape cannot be recognized.

[Resin leakage]
The resin leakage after injection molding was evaluated in the following three stages.
○: The post-filled resin does not protrude toward the flocked surface from the flocked base.
(Triangle | delta): The protrusion to the flocked surface side is 0.5 mm or less, and the resin with which the back filling was carried out is confirmed only to some hair bundles.
X: The post-filled resin has a protrusion to the flocked surface side of more than 0.5 mm, or a protruding protrusion across the entire hair bundle is confirmed.

[Flocking mistake]
The flocking error was evaluated in the following three stages.
○: The hair can be planted continuously with a hair transplanting device.
(Triangle | delta): Although hair can be planted continuously with a hair transplantation apparatus, the thing in which the insertion amount to a hair transplant base part is inadequate generate | occur | produces, or a hair for fallen around a hair transplant base part.
X: The hair bundle cannot be inserted into the base, or the hair falls off around the base of the hair transplantation, and the hair transplantation device cannot continuously plant the hair.

[For hair tip alignment]
The alignment of the tips of the hair after flocking was evaluated in the following three stages.
◯: A predetermined alignment form is formed.
(Triangle | delta): Although the predetermined alignment form is formed, the protrusion of the hair which needs correction can be seen.
X: The alignment form has a partial defect.

[Comparative Examples 1 to 12]
Flocking was carried out in the same manner as in Example except that the area ratio (As / Ai), the hair density in the sleeve, and the hair density in the flock hole were out of the scope of the present invention.

  As shown in Table 1, the toothbrush of the example in which the area ratio (As / Ai), the bristle density in the sleeve, and the flocking density are within the scope of the present invention is the orientation of the bristle bundle compared to the toothbrush of the comparative example. It was confirmed that the hair was excellent and the hairs were neatly aligned.

DESCRIPTION OF SYMBOLS 1 Hair separation | transfer apparatus 2 Sleeve 3 Transfer means 4 Support means 6 Feed means 60 for hair 60 Extrusion pin

Claims (1)

After the bristle cut to a predetermined length is introduced into the introduction hole of the sleeve, the introduced bristle is delivered from the introduction hole of the sleeve and is then passed through the flocking hole of the flocking base. A method for manufacturing a brush comprising a step of inserting into a hair bundle insertion hole for a bundle holder,
The hair bundle holder is for fixing a brush body provided with the flocked base,
For delivery of the hair from within the sleeve, an extrusion pin that can be inserted into the sleeve is used,
The extrusion pin has a cross-sectional shape in which a portion (L4) having a predetermined length from the tip portion thereof corresponds to a cross section perpendicular to the length direction of the straight portion in the introduction hole of the sleeve, and the tip of the extrusion pin The part is formed so as to correspond to the shape of the tip of the hair bundle insertion hole,
The diameter of the bristle bundle insertion hole is set larger than the diameter of the flock hole of the brush body,
The ratio (As / Ai) of the cross-sectional area As orthogonal to the axial direction of the introduction hole in the sleeve to the cross-sectional area Ai orthogonal to the axial direction of the flock hole is 1.02 to 1.3, and the sleeve A brush which introduces the hair with a hair density of 47 to 75% into the hair, and then sends the introduced hair from the sleeve and inserts the hair into the flock hole with a hair density of 60 to 80%. Manufacturing method.

Images