JPH09220126A - Brush producing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively obtain in high productivity a brush of such a type that bristles and the handle are integrally formed and in which transplanting strength of the bristles is high, no burr occurs, and the bristless stand good. SOLUTION: A bundle 1 of bristles is inserted into each of a plurality of bristles bundle insertion holes 4 provided in a forming mold 5. Ends 11 of the bristle bundles projecting from the forming mold 5 are heated and melted by a heating means of a heater 7, thus forming an integrally fused member 2 in which the neighboring bristles bundles 1 are connected. A cavity 8 having therein the fused member 2 is formed in a handle forming mold 6 and a forming material is injected into the cavity 8 and is welded as a handle head part. After that, when detaching the handle from the forming mold 5, the bundles 1 of bristles are pulled for a predetermined amount from the bristles bundle inserting holes 4 while keeping the continuation of the bundle 1 of bristles by an extruding pin (not shown) or other extruding means and are cut by cutting means such as a cutter 9 and a fixed part 91 at a predetermined length position. Thus, the brushes can be effectively and continuously produced. By embedding the fused member 2 in the forming material in the cavity, the high-quality brush in which no burr occurs in the bristles transplanted part and the bundles of bristles and the transplanting strength is high can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a brush, such as a toothbrush, a hairbrush, a body brush or a cleaning brush, in which a plastic brush portion is integrated at the time of molding a handle portion, and an apparatus therefor.

[0002]

2. Description of the Related Art Recently, a synthetic resin bristle bundle is integrated at the time of molding of the handle portion, instead of a brush whose bristle bundle is fixed to the hair-implanting hole in the handle portion with a metal piece or a metal wire. Is proposed. Conventionally, in this type of brush, the bundle of bristles that have been bundled is melted to form an enlarged portion, and the enlarged portion is put into a mold for forming a handle portion and injection-filled with a plastic material for the handle portion to make a plastic. It is known that the respective hair bundles are integrally fixed in the handle portion by curing (No. 6-16725, No. 2-503150).

[0003]

SUMMARY OF THE INVENTION In the conventional method for flocking a bristle member or brush by fusing the ends of a hair bundle, and then injecting a synthetic resin molding material into a mold, In order to increase the strength (difficulty of pulling out the hair bundle from the molded body), it is preferable to inject the molding material into the mold with the end of the hair bundle deeply inserted into the mold, but injection molding The molding material flows out from the through hole due to the pressure at the time and burrs are generated.For example, a bundle of fusing or non-fusing one end is inserted into the mold and the synthetic resin material is injected to the handle part and the bristles. When the hair bundle B is inserted into the hair bundle insertion through-hole as shown in FIG. 7 when the hair bundle is integrated, a gap C is formed on the outer periphery,
The resin injected for forming the handle into the gap C rises due to injection (injection) pressure or the like, and the outer periphery of the hair bundle and /
Or, there is a case where a so-called burr D, which is a protrusion of the resin that enters between the tufts of hair, is generated. [Fig. 7]

This burr is a part of the molding material exuding from the gap between the hair bundle and the through hole. However, the burr density in the through hole is increased, and molding such as injection pressure or injection speed is performed. By adjusting the conditions, it is possible to reduce the incidence and size of burrs to some extent, but burrs protruding from the flocked surface impair the product appearance, and large burrs may damage the oral cavity. However, there is a problem in that the surface of the flocked part is easily stained and becomes unclean. Therefore, in order to prevent burrs from occurring, the fused mass at the protruding end of the hair bundle is made into a fused mass having a cross section larger than the cross section of the through hole, and the through hole is closed by this fused mass when the molding material is injected ( Japanese Patent Publication No. 6-16725) is also proposed, but since the fused mass of the hair bundle is near the head surface, the depth of the hair transplant becomes shallow, and the holding power of the hair bundle for brush, that is, the so-called hair transplant strength is sufficiently satisfied. However, there was a defect that the tufts tended to spread outward from the root part of the transplanted hair, and the hairiness was poor. In addition, the method of inserting the fused mass of the hair bundle deeply into the mold of the head part (Tokuhyo 2-503150) requires a mold system because it is necessary to prevent the resin from entering around the hair bundle. There is a drawback that it becomes complicated and the manufacturing cost becomes high, and in any case, it is complicated and it is not possible to improve productivity by inserting the hair bundle into the hair bundle insertion hole or into the cavity. was there. The present invention is intended to easily eliminate these conventional drawbacks, has a simple mold structure, significantly improves productivity without requiring a special mold system, and has a high hair transplant strength. Another object of the present invention is to obtain a method for producing a brush in which bristles with good bristling can be obtained and burr does not protrude above the bristling surface.

[0005]

According to the present invention, one end of a hair bundle made of thermoplastic synthetic resin is heat-fused and inserted into and held in a cavity in a handle mold, and a molding material is injected into the cavity. Then, in the in-mold manufacturing method of the brush having the flocked portion integrally fixed to the handle head portion by curing of the molding material, a large number of filament bundles for filament are fed out from the winding reel, and a plurality of them are provided on the molding die via the filament guide. Insert the hair bundle into the hair bundle insertion hole,
The end of the hair bundle protruding from the molding die is heated and melted to form and connect to an integrated fusion piece in which adjacent hair bundles are connected to each other, and a cavity containing the fusion piece inside is formed by a handle molding die. After forming and injecting the molding material into the cavity and fixing it, pull out a fixed amount of the hair bundle from the molding die with the extrusion pin through the hair bundle insertion hole when releasing the handle from the molding die at a predetermined length position. Each hair bundle is cut.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the embodiment of the present invention, a large number of hair bundle filaments made of thermoplastic synthetic resin are fed from a winding reel, and a plurality of hair bundle insertion holes are provided in a molding die through a filament guide. Insert the hair bundle for each inside,
The end of the hair bundle protruding from the molding die is heated and melted to form and connect to an integrated fusion piece in which adjacent hair bundles are connected to each other, and a cavity containing the fusion piece inside is formed by a handle molding die. After forming and injecting the molding material into the cavity and fixing it, pull out a certain amount of the hair bundle from the molding die with the extrusion pin through the hair bundle insertion hole at the time of releasing the handle, and pull out the hair bundle at a predetermined length position. By cutting each hair bundle with, it is possible to work continuously while maintaining the introduction state of the hair bundle into the hair bundle insertion hole, and the hairs arranged on the outer periphery of the hair bundle are in close contact with each other. There is no gap between the hairs that are held and the hair is planted in the handle without burrs. In addition, the hair pressure does not cause the hair bundles to rotate or tilt due to the injection pressure of the molding material. It is possible to obtain strength, fluffing is improved, and scraping is good. By being made to have the design design margin, without the need for special mold system,
It is possible to efficiently obtain a brush having a high flocking strength, a flocked state with good bristling, and a good appearance quality by continuous production.

[0007]

EXAMPLE An example of the present invention will be described with reference to the examples of FIGS. 1 to 3. The filament of the hair bundle 1 made of thermoplastic synthetic resin is fed from the winding reel 10 to the filament guide 11.
Inserting the hair bundle 1 for each use tuft insertion holes 4 provided plurality of molding die 5 via a heat melt the use bristle bundle ends 1 ₁ projecting from the molding die 5 with the heating means of the heater 7 Then, the adjacent hair bundles 1 are molded and connected to the integrated fusion piece 2 which is connected to each other, and the cavity 8 containing the fusion piece 2 therein is formed by the handle molding die 6, and the cavity 8 is formed in the cavity 8. After injecting the molding material and fixing it at the handle head portion 13, the hair bundle 1 is continuously connected from the hair bundle insertion hole 4 at the time of releasing the handle from the molding die 5 by an extruding pin (not shown) or other releasing means. fixed amount withdrawal while the, by cutting each for hair bundle 1 by cutting means such as a cutter 9 and the fixed portion 9 ₁ at a predetermined length position, in which it is possible to efficiently continuously producing a brush.

Further, in the present invention, as a device used in this brush manufacturing method, the hair bundle insertion hole 4 is formed in the molding die 5 so as to communicate with the cavity 8 provided in the handle molding die 6, After the hair bundle 1 is inserted into the hair bundle insertion hole 4 in the initial stage, it can be operated continuously, and the outer peripheral shape of the hair bundle insertion hole 4 is the fusion piece 2 of the hair bundle 1. By closing with no gap, the molding material is prevented from entering during in-molding so that no burr is generated.

The insertion means for the hair bundle 1 is as follows.
Only in the initial stage, the hair bundle is pushed into the hair bundle insertion hole, and then continuously moved and inserted to form a fused mass or fused piece at the end of the hair bundle, and then the fused mass or fused piece In mold in the cavity, pull out the bristle bundle to a predetermined length at the same time as releasing the handle, and then use the cutting process at a position away from the molding die of the pulled bristle bundle The fused mass at the end of the hair bundle or the fused piece can be easily heat-molded, and productivity can be improved by repeating the subsequent steps.

In this embodiment, at the time of in-molding, that is,
When the molding material is injected into the handle molding die 8, since the lower part of the hair bundle is held integrally, the hair bundles can be maintained in a substantially right angle direction without tilting or tilting due to the injection pressure, and the hair transplant strength is also high. It is possible to increase the strength by about 3 times that of a single hair bundle. In this case, all of the projecting ends of the hair bundle 1 are heated and fused into a fused mass, and then each fused mass is pressed against a molding plate (not shown) to form a substantially hemispherical or conical or flat shape. The fusion piece 2 is formed into a shape and integrally connected so that the tangents are connected to each other, and the fusion piece 2 is embedded in the handle head portion 3. In order to connect and integrate the individual hair bundles 1, a fused piece may be formed and then a molding plate may be pressed to form a fused piece. However, a heater provided with a molding die section may be used. It is also possible to form the fused piece 2 while fusing.

In this case, the supporting hair bundle 1 is introduced into the hair bundle insertion hole 4 provided in the molding die 5 so that one end 1 _{1 of the} hair bundle 1 ₁
And the protruding end is formed by a heating plate such as a heater 7 or heating means such as hot air or infrared rays to form a fused piece 2 having a cross section larger than the cross section of the hair bundle insertion hole 4 and then the cutter 9. It is useful for molding the fusion piece 2 with one end left protruding at the position for cutting with, and the fusion piece 2 is positioned in the cavity 8 of the handle molding die 6 6 is closed, or after the mold is closed, the fusion piece 2 is positioned in the cavity 8 and then the molding material is introduced, and the hair bundle 1 is integrally transplanted to the handle portion 3 by handle molding by hardening the molding material. The resulting brush is a brush with high flocking strength and good quality.

The fusion piece 2 of the bristle bundle 1 is pushed into the cavity 8 of the handle molding die 6 by an extrusion pin (not shown).
The hair bundle 1 may be pushed and moved a little at a time, and the hair bundle 1 may be guided and operated at the same time. The insertion distance of the hair bundle 1 depends on the thickness of the base of the flocking member or the thickness of the brush head portion. Depending on the situation, the hair bundle can be arbitrarily selected, and consideration is given so that the tuft does not spread outward from the root of the planted part, but stands straight and maintains good tufting.

In the example of FIGS. 4 to 6, the tip end surface of the bristle bundle 1 fitted into the bristle bundle insertion hole 4 of the molding die 5 has a concave end surface 5 ₁
And a fused piece 2 formed on each of the lower end portions of the hair bundles 1 by heating means, and the fused pieces are integrally connected by connecting the circumscribed edges of the fused pieces of the adjacent hair bundles. At the same time, it is configured as a fusion piece 2 in which a concave portion or a through space 2 ₁ is formed in a diagonally central portion of each hair bundle arranged as required, and the fusion piece 2 is embedded and solidified in the molding material in the cavity 8. By implanting and holding the tufts in the handle head portion 3, the tufts can be tufted without rotating due to the injection pressure of the molding material, and a sufficient tufting strength can be obtained. Since the root of the bundle is filled and the integrated hair bundle can be fixed, the hair bundle can be shallowly planted, which contributes to thinning the head portion 3 on the bristle implant member or brush.

In this case, the hair bundle introduced into the hair bundle insertion hole 4 provided in the molding die 5 can be cut by the cutter 9 so that one end of the hair bundle is aligned and projected. (FIG. 4), the projecting end portion is made into a fusion piece 2 that integrally connects by connecting the circumscribed edges of the fusion masses of the hair bundles 1 that are adjacent to each other by heating with the heater 7 (FIGS. 5a and 5b). The fusion piece 2 is positioned in the cavity 8 of the handle molding die 6, the handle molding die 6 is closed, and then the molding material is introduced, and the handle molding is performed by curing the molding material.
The handle is a brush in which the above-mentioned hair bundles are integrally transplanted (Fig. 6). It is also possible to perform the injection molding with the molding die 6 slidingly retracted at the time of in-molding, or the fusion piece 2 is pushed in with a push pin and inserted into the cavity 8.

The features of the present invention include the following manufacturing method. The bristle bundle is introduced into the bristle bundle insertion hole communicating with the cavity of the handle molding die, and the bristle bundle end is projected to form a fused mass having a cross section larger than the cross section of the bristle bundle insertion hole by the heating means. And a method for manufacturing a brush, in which the fused mass is in-molded inside the cavity. A method of manufacturing a brush, wherein fusion hair pieces are expanded and arranged in an outer periphery of a bristle bundle with a concave end face on an opening end side of a bristle bundle leading side of a hair bristle bundle insertion hole formed in a handle molding die, and in-molded.

[0016]

Industrial Applicability According to the present invention, the bristle bundle ends are inserted through the bristle bundle insertion holes provided in the molding die for the thermoplastic synthetic resin bristle bundle, and the bristle bundle ends projecting from the molding die. Is melted by heating to form an integrated fusion piece in which adjacent hair bundles are connected to each other, and a cavity containing the fusion piece inside is formed by a handle molding die, and a molding material is placed in the cavity. After injecting and fixing, pull out a fixed amount of the hair bundle from the molding die with the push pin through the hair bundle insertion hole when releasing the handle, and cut each hair bundle at a predetermined length position. In addition, the handling of the bristle bundle is remarkably simplified and suitable for continuous production. Since there is no gap at the end of the bristle bundle, the molding resin does not flow out into the insertion hole during injection molding and burr can be prevented. , It is necessary to close the gap between the hair bundle and the hair bundle holding hole in the enlarged hair bundle. Ku, since the use tufts can be held by being integrally connected, even prevents twisting of the hair bundle with sufficient flocking strength can be obtained, hair standing is improved by a large margin.
In addition, it is possible to obtain a sufficient hair transplanting strength without rotating or inclining each hair bundle due to the injection pressure of the molding material. By having a design allowance, it is possible to obtain a brush with a high appearance quality and a good appearance, at a low cost, with high flocking strength and a flocked state with good bristling, without the need for a special mold system. .

[Brief description of drawings]

FIG. 1 is an enlarged vertical sectional view of a manufacturing process according to an embodiment of the present invention,
(A) is a hair bundle end pretreatment step, (b) is a hair bundle end molding step, (c) is a hair bundle end molding step, (d) is an in-mold step, and (e) is a mold release step. Show.

2 is a longitudinal sectional view of a product obtained by the manufacturing method of the example of FIG.

3 is an enlarged perspective view of a portion of the example of FIG.

FIG. 4 is an enlarged vertical cross-sectional view of a manufacturing process of another embodiment of the present invention.

5 is an example of the hair bundle obtained in FIG. 4, (a) is an enlarged cut-away side view of the hair bundle, and (b) is an enlarged plan view thereof.

FIG. 6 is a vertical cross-sectional view of an in-mold process using the hair bundle of FIG.

FIG. 7 is an enlarged perspective view of a hair tuft in the state of using a conventional hair tuft.

[Explanation of symbols]

 1 Hair bundle 2 Fused piece 3 Handle part 4 Hair bundle insertion hole 5 Molding die 6 Handle molding die 7 Heater 8 Cavity 9 Cutter 10 Winding reel 11 Filament guide

Claims (1)

[Claims] 1. A handle is formed by heating and fusing one end of a hair bundle made of a thermoplastic synthetic resin, inserting and holding it in a cavity in a mold for molding a handle, injecting a molding material into the cavity, and hardening the molding material. In the in-mold manufacturing method of a brush having a flocked part integrally fixed to the head part, a large number of hair bundle filaments are fed out from a winding reel and inserted into a plurality of hair bundle insertion holes provided in a molding die through a filament guide. Each of the hair bundles is inserted, and the ends of the hair bundles protruding from the molding die are heated and melted to form and connect the adjacent hair bundles with each other into an integrated fusion piece, and the fusion piece is included inside. The cavity is formed with the handle molding die, the molding material is injected into the cavity and fixed, and then the hair bundle is continuously connected from the hair bundle insertion hole when the handle is released from the molding die with the extrusion pin. One A method for manufacturing a brush, which comprises pulling out a fixed amount and cutting each bristle bundle at a predetermined length position.