KR20210009978A - Method for manufacturing toothbrush and toothbrush manufactured by the method - Google Patents

Abstract

The present invention provides a method for manufacturing an anchorless toothbrush having a soft brushing feeling and excellent cleaning power with a constant quality by comprising the following steps: heat-treating a tapered part (length of 3 to 8 mm) of fine bristles (thickness of 0.07 to 0.14 mm); implanting fine bristles, in which tapered part is heat-treated, into a large-area hair transplanting holes (19 mm^2 or more in area) of a head insert; and coupling the head insert in which fine bristles are implanted to a toothbrush head. In addition, the present invention also provides the anchorless toothbrush manufactured by the method.

Description

Toothbrush manufacturing method and toothbrush manufactured by this method {METHOD FOR MANUFACTURING TOOTHBRUSH AND TOOTHBRUSH MANUFACTURED BY THE METHOD}

An embodiment of the present invention relates to an anchorless toothbrush and a method of manufacturing the same.

The method of using a metal anchor to plant the bristles in the toothbrush head of the toothbrush has a severe dropout of the bristles compared to the anchorless method without using an anchor, and it is difficult to diversify the arrangement, size, or shape of the hair removal holes. There is a problem. Accordingly, the toothbrush industry prefers the anchorless method and is actively conducting research and development on anchorless toothbrushes, and the anchorless toothbrush manufactured at high cost using advanced manufacturing equipment is the premium functional toothbrush market. Leading the way.

In general, an anchorless toothbrush includes a toothbrush head, a head insert coupled to the toothbrush head, and bristles implanted in the hair removal holes of the head insert. In each of the hair transplant holes, bristles are inserted in the form of a bundle having a cross section corresponding to each of the hair hair holes. In the inserted hair bundles, the base portions of the bristles are attached to the rear surface of the head insert by thermal fusion.

Here, as the bristles, a tapered bristle having a tapered portion of a shape gradually shrinking toward the tip is applied to the tip to be more advantageous in terms of removing tartar, plaque or preventing damage to the gums.

Equipment for manufacturing such an anchorless toothbrush may include at least any one or more of a hair manufacturing device, a hair insertion device used in the hair transplantation step, a heat fusion device used in the hair growth step, and a toothbrush stand forming device including a toothbrush head. have.

In the anchorless toothbrush, if the hair removal holes are formed in a large area, the number of hair removal holes can be reduced, thereby simplifying the toothbrush manufacturing process and the configuration of equipment, but it is still difficult to commercialize it. The reason for this is as follows.

When the hair removal hole is formed in a large area (for example, 4.9 mm2 or more), the number of bristles constituting the hair bundle is relatively large, so that the thickness (diameter) 0.15 mm or more and Even if fine hairs having a tapered length of 1 to 5 mm are applied, excessive cleaning power is generated, so the degree of abrasion of the teeth during brushing is quite large and the degree of irritation of the gums is inevitably severe.

If the brush heads are thinner and have a longer taper length, so that softer fine hairs (for example, less than 0.15 mm in thickness and 3 to 8 mm in taper length) are applied, the cleaning power is increased to an excessive level even if the hair removal hole is formed in a large area. Can be suppressed. However, in this method, since the thin tapered part is longer than the other part of the fine hair, the tapered part is too soft and very sensitive due to the weak elasticity, and it is very difficult to consistently handle the bristles by the toothbrush manufacturing facility. none. Of course, this can lead to poor processing and uneven quality.

International Publication No. WO1995/026149 (1995.10.05.) Republic of Korea Patent Publication No. 10-0130932 (1998.04.16.) Republic of Korea Patent Publication No. 10-0233303 (1999.12.01.) Republic of Korea Patent Publication No. 10-0573898 (2006.04.26.)

An object of the present invention is to provide a method for easily manufacturing a toothbrush having a soft toothbrush and excellent cleaning power with constant quality, a toothbrush manufactured by this method, and the like.

The problem to be solved is not limited thereto, and other problems that are not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

According to an embodiment of the present invention, the step of cutting a filament having a thickness of 0.07 to 0.14 mm to a set length (filament cutting step); Forming a tapered portion having a taper length of 3 to 8 mm on at least one or more of both ends of the cut filament to obtain fine hair (taper processing step); A method of manufacturing a bristles may be provided, including the step of increasing the crystallinity of the tapered portion by heat treating the tapered portion of the obtained fine hair (heat treatment step). In this case, the filament may be formed of poly-butylene-terephthalate (PBT).

Here, the heat treatment step transfers heat to the tapered portion of the fine hair to impart crystallinity to the tapered portion. According to the heat treatment step, the crystallinity of the tapered portion is increased and hardened by the transferred heat, thereby improving strength and resilience (elasticity).

The heat treatment may heat the tapered portion at a temperature of 200 to 600°C and an air volume of 100 to 200 L/min for 1 to 12 seconds using a hot air fan.

The heat treatment may provide hot air in the longitudinal direction of the fine hairs (cut the filaments) toward the end of the tapered portion.

The heat treatment may be performed in the order of heating and then cooling using the hot air blower.

The cooling may be performed for 5 to 10 minutes at a temperature of -20°C or less in a cooling chamber blocked from the outside.

According to an embodiment of the present invention, the step of preparing a head insert having at least one or more hairdressing holes having a large area of 19 mm 2 or more (head insert preparation step); Preparing fine hairs having a thickness of 0.07 to 0.14 mm and a tapered length of 3 to 8 mm in the tapered portion (preparing fine hairs); Heat-treating the tapered portions of the prepared fine hairs to increase the crystallinity of the tapered portions (heat treatment step); Planting the heat-treated fine hairs into the large-area hair transplanting holes of the prepared head insert (hair transplantation step); A method for manufacturing a toothbrush may be provided, including the step of coupling the head insert in which the fine hairs are planted to the toothbrush head (head insert coupling step). In this case, the microhairs may be formed of polybutylene terephthalate (PBT).

The method of manufacturing a toothbrush according to an embodiment of the present invention may further include removing static electricity from the heat-treated fine hairs (an antistatic step) before the hairs are planted.

In the step of removing static electricity from the fine hairs, ionized gas may be sprayed onto the heat-treated fine hairs.

According to an embodiment of the present invention, by being manufactured by the method of manufacturing a toothbrush as described above, a toothbrush head; A head insert coupled to the toothbrush head and having at least one hair transplant hole having a large area of 19 mm 2 or more; A toothbrush may be provided, which is planted in the large-area hairdressing hole of the head insert, has a thickness of 0.07 to 0.14 mm, a taper length of a taper portion is 3 to 8 mm, and includes microhairs having a heat treatment of the taper portion. At this time, some of the fine hairs are different from at least one or more of a thickness and a tapered length of the tapered portion, so that a plurality of fine hairs may be implanted.

According to an embodiment of the present invention, the step of increasing the crystallinity of the tapered portion by heat-treating the tapered portion of the fine hairs; Transplanting the heat-treated fine hairs into the hair transplanting holes of the head insert; A method of manufacturing a toothbrush may be provided, including the step of coupling the head insert in which the fine hairs are planted to the toothbrush head. And, a toothbrush manufactured by such a toothbrush manufacturing method may be provided. In this case, the fine hairs have a thickness of 0.07 to 0.14 mm, a tapered length of the tapered portion of 3 to 8 mm, and may be formed of polybutylene terephthalate (PBT).

The means for solving the problem will be more specific and clear through examples, drawings, and the like described below. In addition, various solutions other than the aforementioned solutions may be additionally presented below.

According to an embodiment of the present invention, before planting fine hairs having a thickness of 0.07 to 0.14 mm and a taper length of 3 to 8 mm in a large area hair growth hole of 19 mm2 or more, heat treatment to increase the crystallinity of the tapered portion with respect to the fine hairs Since the elasticity of the tapered portion is improved by performing a toothbrush, a toothbrush having a soft toothbrushing feeling, excellent cleaning power, and improved durability can be easily manufactured with a constant quality by a toothbrush manufacturing facility.

1 is a perspective view showing a toothbrush according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view illustrating part A of FIG. 1.
3 is a perspective view of the head insert shown in FIGS. 1 and 2.
4 is a front view of the bristles shown in FIGS. 1 and 2.
5 is a flowchart illustrating a method of manufacturing a toothbrush according to an embodiment of the present invention.
6 is a perspective view showing a bristle heat treatment step of a method for manufacturing a toothbrush according to an embodiment of the present invention.
7 and 8 are cross-sectional views illustrating a hair transplantation step in a method for manufacturing a toothbrush according to an embodiment of the present invention.
9 and 10 are cross-sectional views illustrating a molding apparatus used in a head insert coupling step of a method for manufacturing a toothbrush according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. For reference, in the drawings referred to to describe the embodiments of the present invention, the size of components and the thickness of lines may be somewhat exaggerated for convenience of understanding. In addition, terms used to describe the embodiments of the present invention are mainly defined in consideration of functions in the present invention, and thus may vary according to the intentions and customs of users and operators. Therefore, it is appropriate to interpret the terms based on the contents throughout the present specification.

As the preservation of natural teeth becomes important due to the weakening of teeth and gums of modern people and the prolongation of lifespan, the development of a toothbrush that combines low wear, mild toothbrushing feeling and excellent cleaning power is required. In order to manufacture a toothbrush with such functionality, a tapered portion is formed and fine hairs made of polybutylene terephthalate (PBT) are widely used, and the thickness, total length and tapered length of the fine hairs, and the size of the hair follicles are properly combined. Therefore, the softness and elasticity of the parent bundle are adjusted to the required level.

Anchorless toothbrush is suitable for simplifying the construction of toothbrush manufacturing process and equipment through the application of large-area hair removal holes, as the arrangement, size, or shape of the hair removal holes can be variously designed, but in order to manufacture to have the mentioned functionality Softer fine hairs should be consistently handled by the toothbrush manufacturing facility.

To this end, the toothbrush manufacturing method according to an embodiment of the present invention prepares a head insert having at least one hair growth hole of 19 mm 2 or more, and a fine hair having a thickness of 0.07 to 0.14 mm and a taper length of 3 to 8 mm. They are planted in a large-area planting hole, and the elasticity of the tapered portions of the fine hairs is improved to a certain level before planting.

First, look at the toothbrush according to an embodiment of the present invention. The configuration of a toothbrush according to an embodiment of the present invention is shown in FIGS. 1 and 2. The toothbrush according to the embodiment of the present invention is an anchorless toothbrush that does not use an anchor to plant the bristles in the toothbrush head, and as shown in FIGS. 1 and 2, the toothbrush holder 10 and the head insert 20 Includes bristles (30). The bristles 30 constituting the brush are planted in the head insert 20, and the toothbrush stand 10 holds the head insert 20 in which the bristles 30 are planted.

The toothbrush stand 10 is formed to have a certain length and thickness in consideration of usability. Referring to Figure 1, the toothbrush stand 10, a toothbrush head 11 disposed in one side in the longitudinal direction, a toothbrush handle 12 disposed in the other side in the longitudinal direction and positioned opposite the toothbrush head 11 ), and a toothbrush neck 13 connecting the toothbrush head 11 and the toothbrush handle 12 between the toothbrush head 11 and the toothbrush handle 12.

The toothbrush head 11 is made of resin. For example, the toothbrush head 11 is made of acrylonitrile butadiene styrene (ABS), acrylonitrile styrene (AS), polypropylene (PP), polyethylene terephthalate (polyethylene). terephtalate, PET), and the like.

The toothbrush handle 12 and the toothbrush neck 13 are made of the same resin as the toothbrush head 11 and are integrally formed with the toothbrush head 11. Alternatively, the toothbrush head 11 and the toothbrush handle 12 may be separately manufactured and then connected to each other through the toothbrush neck 13. The toothbrush neck 13 may be integrally formed on at least one of the separate toothbrush head 11 and the toothbrush handle 12.

2, the toothbrush head 11 has an insert groove 14 for holding the head insert 20 is formed concave. Of course, the head insert 20 is inserted into the insert groove 14.

The configuration of the head insert 20 is shown in FIG. 3. As shown in FIG. 3, the head insert 20 is formed to have a thin plate-like structure as viewed as a whole. This head insert 20 has one surface in the thickness direction, a rear surface in the other direction in the thickness direction, and a circumferential surface 213 defining a circumference. In addition, the head insert 20 has hair removal holes 21 and 22 for hair removal of the bristles 30. The hairdressing holes 21 and 22 are formed in a shape that penetrates the head insert 20 in the thickness direction of the head insert 20, respectively.

When the head insert 20 is coupled to the toothbrush head 11 and inserted into the insert groove 14, the surface side protrudes from the toothbrush head 11 through the inlet of the insert groove 14. According to the configuration in which the surface of the head insert 20 protrudes from the toothbrush head 11, the toothbrush head 11 having a circumference larger than that of the head insert 20 can be formed with a relatively thin thickness.

As the hair transplantation holes 21 and 22, at least one or more large-area hair-dressing holes 21 formed to have an area of 19 mm2 or more and a small-area hair-dressing hole 22 formed to have an area of less than 19 mm 2 are each applied. The number, arrangement structure, size, or shape of the large-area hair transplantation holes 21 that are 19 mm 2 or more and the small-area hair transplantation holes 22 that are less than 19 mm 2 are not limited to those shown in FIG. 3 and may be variously modified. In extreme cases, only at least one or more large-area hair transplanting holes 21 may be formed in the head insert 20.

For reference, the cross-sectional size of the hair transplant holes 21 and 22 may be constant or may be designed to be different in a certain section or point. For example, some of the hair transplanting holes 21 and 22 may be formed in a shape that gradually shrinks from the rear surface to the surface of the head insert 20. In consideration of this point, the area of the hair transplant holes 21 and 22 refers to the area of the opening on the surface of the head insert 20.

In FIG. 4, a bristle 30 is shown. The bristles 30 constituting the brush are formed of a meltable thermoplastic resin. Referring to FIGS. 2 and 4, the bristles 30 are inserted into the hair transplant holes 21 and 22 in the form of a bundle having a size corresponding to the area of each of the hair transplant holes 21 and 22, and the base portion 34 It is firmly attached to the rear surface of the head insert 20 by heat fusion to provide a brush on the surface side of the head insert 20. The material of the bristles 30 may be nylon, poly-butylene-terephthalate (PBT), or the like.

As the bristles 30, first bristles 31 that are planted in the large-area hairdressing hole 21 and the second bristles 32 that are planted in the small-area hairdressing hole 22 are applied.

As shown in Fig. 4, each of the first bristles 31 that are planted in the large-area hairdressing hole 21 has a thickness (diameter, D) of 0.07 to 0.14 mm, and the thickness at the tip decreases toward the tip. A tapered portion 33 of the shape is formed, the taper length (L) of the tapered portion 33 is 3 to 8 mm, and the taper portion 33 is heat treated to increase the crystallinity of the tapered portion 33. to be.

In the first hair bundle consisting of the first micro hairs 31 implanted in the large-area hair transplantation hole 21, some micro hairs have different specifications of at least one of the thickness (D) and the tapered length (L), The first hair bundles planted in the area hair transplant hole 21 may be composed of two or more types of fine hairs having different specifications in the range of a thickness (D) of 0.07 to 0.14 mm and a taper length (L) of 3 to 8 mm. Alternatively, when a plurality of large-area hair transplantation holes 21 are provided, fine hairs of other species may be implanted in the selected large-area hair transplantation holes 21.

Each of the second bristles 32 planted in the small-area hairdressing hole 22 has a thickness (diameter, D) of 0.15 to 0.20 mm, and a tapered portion 33 formed at the tip whose thickness decreases toward the tip. In addition, the tapered portion 33 may have a taper length L of 1 to 5 mm.

Next, a method of manufacturing a toothbrush according to an embodiment of the present invention will be described. 5 illustrates a method of manufacturing a toothbrush according to an embodiment of the present invention. As shown in Figure 5, the toothbrush manufacturing method according to the embodiment of the present invention includes a head insert preparation step, fine hair preparation step, heat treatment step, antistatic step, hair transplantation step, and head insert bonding step (toothbrush stand forming step).

Head insert preparation step : A head insert 20 is prepared in which at least one of a large-area hair transplantation hole 21 having an area of 19 mm2 or more and a small-area hair transplantation hole 22 having an area less than 19 mm2 is formed. This head insert 20 may be prepared by injection molding.

Preparing fine hair : Prepare first fine hairs 31 to be planted in the large-area hair transplantation hole 21 and second fine hairs 32 to be planted in the small-area hair planting holes 22, respectively.

The first fine hair 31 is a step of preparing a monofilament having a thickness D of 0.07 to 0.14 mm, cutting the prepared monofilament to a required length, and a tapered length at one end of the cut monofilament. (L) can be prepared and prepared by a method including the step of forming the tapered portion 33 of 3 to 8 mm. The second fine hair 32 is a step of preparing a monofilament having a thickness (D) of 0.15 to 0.20 mm, cutting the prepared monofilament to a required length, and a tapered length (L) at one end of the cut monofilament. It may be prepared and prepared by a method including the step of forming a tapered portion 33 of 1 to 5 mm.

Here, the tapered portion 33 of the first and second fine hairs 31 and 32 is reduced by immersing one end of the cut monofilament in sulfuric acid having a concentration of 60 to 98% and a temperature of 80 to 200°C. After that, it is cooled in cold water, neutralized with a sodium hydroxide (NaOH) solution or potassium hydroxide (KOH) solution having a concentration of 30 to 70%, followed by washing with water and drying with hot air sequentially. Can be formed.

Alternatively, the tapered portion 33 of the first and second fine hairs 31 and 32 has a temperature of 70 to 100° C. and a temperature of 70 to 100° C. and potassium hydroxide (KOH). It may be formed by immersing in a neutralized 10 to 40% m-cresol (m-Cresol, molecular weight: 108.14 g/mol) solution for 0.5 to 1.0 hours to perform weight loss treatment.

Heat treatment step : By performing heat treatment on the tapered portions 33 of the first fine hairs 31 to be planted in the large-area hair growth holes 21 among the prepared first and second fine hairs 31 and 32, the first fine hairs ( The elasticity of the tapered portions 33 of the first fine hairs 31 is improved by increasing the strength and crystallinity of the tapered portions 33 of the 31). This heat treatment step includes a heating process and a cooling process, and a cooling process is performed after the heating process.

A hot air machine is used in the heating process. 6 is a perspective view illustrating a heating process during a heat treatment step. As shown in FIG. 6, the first fine hairs 31 are heated by a hot air in a bundle shape, and the cross-sectional area A1 of the bundle is a cross-sectional area A2 of the nozzle 40 for spraying hot air from the hot air machine. It is provided to have a size 10% smaller than ). In the heating process, the seedling bundle composed of the first fine hairs 31 may be provided to have a cross section corresponding to the large-area hair transplantation hole 21, and the nozzle 40 may be It may be provided to have a cross-sectional area (A1) 10% smaller than that of the injection port cross-sectional area (A2).

The model bundle is arranged to face the nozzle 40 of the hot air machine in front, so that the hot air from the nozzle 40 is directed toward the end of the tapered portion 33 of the first fine hairs 31 in the longitudinal direction of the first fine hairs 31 It is provided in a direction parallel to the. It is preferable that the hot air temperature is 200 to 600°C, the air volume is 100 to 200 L/min, and the heating time is 1 to 12 seconds.

The cooling process takes place in a cooling chamber that is isolated from the outside. The first fine hairs 31 that have undergone the heating process are put into the cooling chamber immediately after the heating process is completed. The cooling process is preferably performed for 5 to 10 minutes at a temperature of -20°C or less.

Anti- static step : From the first fine hairs to be planted in the large-area hair transplantation hole 21 (the fine hairs with the tapered portion 33 are heat-treated) 31 and the second fine hairs 32 to be planted in the small-area hair transplantation hole 22 Eliminate static electricity.

In such an antistatic step, an ionized gas is injected to the first and second fine hairs 21 and 22 to remove static electricity from the first and second fine hairs 21 and 22.

In the static elimination step, an apparatus including a chamber providing a static elimination space and an injector for injecting ionized gas to the first and second fine hairs 21 and 22 injected into the static elimination space may be used. The ionized gas is preferably injected toward the end of the tapered portion 33 and the end of the base portion 34 so that static electricity is entirely removed from the first and second fine hairs 21 and 22.

Hair transplantation step : The first and second fine hairs 31 and 32 from which static electricity has been removed are transplanted into the prepared head insert 20. The hair transplantation step includes a hair insertion process and a thermal fusion process, and a thermal fusion process is performed after the hair insertion process. This hair transplantation step is illustrated in FIGS. 7 and 8. Referring to Figs. 7 and 8, a hair transplantation step will be described as follows.

First, the first fine hair (thickness 0.07 to 0.14 mm, taper length 3 to 8 mm) in the large area hair transplantation hole (19 mm2 or more) 21 and the small area hair growth hole (less than 19 mm2) 22 of the head insert 20 , Tapered partial heat treatment) 31 and second fine hairs (thickness 0.15 to 0.20 mm, taper length 1 to 5 mm) 32 are inserted, respectively. In this hair insertion process, a hair insertion device of a toothbrush manufacturing facility is used. 7 shows a state in which the first fine hairs 31 are inserted in the form of bundles into the large-area hair transplanting holes 21 using a hair insertion device.

Referring to FIG. 7, the hair insertion device includes a storage container (not shown) in which bristles (fine hairs) are accommodated, a picking and transfer unit for taking out and transferring the bristles stored in the storage container, and taking out -It may include a pusher (pusher) that pushes the bristles held by the transfer unit and inserts them into the hair removal holes 21 and 22 of the head insert 20. The take-out-transfer unit includes tubes 51 corresponding to the hair transplant holes 21 and 22, and bristles taken out from the storage container are introduced into the inner space of the tubes 51. The take-out-transfer unit holding the bristles is moved so that the tubes 51 abut and communicate with the corresponding hair removal holes 21 and 22, respectively. The pusher includes plungers 52 inserted into the tubes 21 and 22 to reciprocate, respectively. When the plungers 52 are moved forward while the tubes 51 are in communication with the hair transplant holes 21 and 22, respectively, the bristles in the tubes 51 are inserted into the hair transplant holes 21 and 22.

In performing the hair insertion process using such a hair insertion device, the toothbrush manufacturing method according to the embodiment of the present invention includes a taper of the first fine hairs (thickness 0.07 to 0.14 mm, taper length 3 to 8 mm) 31 Since the portion 33 has improved elasticity in the heat treatment step, the first fine hairs 31 can be inserted into the large-area hair transplantation holes 21 with a certain quality. That is, the first fine hairs 31 before performing the heat treatment step are too soft and sensitive due to the weak elasticity of the tapered portion 33, so they are bent even with small external forces such as micro-vibration during the extraction, transfer and insertion process by the hair insertion device, Since tremor occurs seriously, it is difficult to perform the process of inserting the hair in a state in which the hair insertion device is uniformly aligned (line in the direction of the hair (vertical) or the line in the hair length end (horizontal)), and it is difficult to insert the hair by bending or shaking. It may get caught in the gap of the device and cause the device to fail. On the other hand, since the first fine hairs 31 after the heat treatment step has an improved elasticity due to the increase in crystallinity of the tapered portion 33, bending and shaking are suppressed during the extraction, transfer and insertion process by the hair insertion device. Therefore, it is possible to perform the hair insertion process in a state in which the hair insertion device is aligned with a certain quality.

In addition, in performing the hair insertion process using such a hair insertion device, in the toothbrush manufacturing method according to the embodiment of the present invention, static electricity is removed from the first and second fine hairs 31 and 32 in the antistatic step. Because of the point, the alignment of the first and second fine hairs 31 and 32 is prevented from being deteriorated by static electricity in the process of taking out, transferring and inserting the first and second fine hairs 31 and 32 by the hair insertion device. can do.

When the hair insertion process is completed, the base portion 34 protruding from the rear surface of the head insert 20 in the first and second fine hairs 31 and 32 inserted into the hairdressing holes 21 and 22 is inserted into the head insert ( Attached to the back side of 20) by thermal fusion. In this heat fusion process, a heat fusion device of a toothbrush manufacturing facility is used. FIG. 8 shows a state in which the base portion 34 of the first fine hairs 31 maintained in a state inserted into the large-area hair transplantation hole 21 by the hair insertion device is fused by a heat fusion device.

Referring to FIG. 8, the heat sealing device may include a heating plate 55. When appropriate heat and pressure are applied to the base portion 34 of the first and second fine hairs 31 and 32 using the heating plate 55, the base portion 34 is melted, and the melt of the base portion 34 is cured. As a result, a molten layer 35 firmly attached to the rear surface of the head insert 20 is formed.

Head insert coupling step (toothbrush stand shaping step) : In order to couple the head insert 20 in which the bristles 30 are planted through the hair transplantation step to the toothbrush head 11 of the toothbrush stand 10, the head insert 20 is a toothbrush head The toothbrush holder 10 buried in (11) is molded.

9 and 10 are cross-sectional views illustrating a molding apparatus used in a head insert coupling step (toothbrush stand shaping step) of a method for manufacturing a toothbrush according to an embodiment of the present invention. As shown therein, the molding apparatus includes an insert injection mold (60). 9 shows the configuration of the insert injection mold 60. 10 shows a state in which the head insert 20 is disposed in the insert injection mold 60 for molding the toothbrush holder 10.

The insert injection mold 60 has a cavity (CA) formed therein. The cavity CA is formed to correspond to the shape of the toothbrush stand 10 in which the toothbrush head 11, the toothbrush handle 12, and the toothbrush neck 13 are integrally formed. When the toothbrush head 11 is coupled with a separate toothbrush handle 12 through the toothbrush neck 13, the cavity CA is formed in the shape of the toothbrush head 11 or the toothbrush head 13 is integrally formed. It may be formed to correspond to the shape of 11).

Such an insert injection mold 60 includes a first mold 61 having a first molding surface 62 formed thereon, and a second molding surface 66 forming a cavity CA together with the first molding surface 62 And a second mold 65 formed therein. When the first mold 61 and the second mold 65 are combined (molded) with each other, the first molding surface 62 and the second molding surface 66 are paired to form a cavity CA.

The head insert 20 in which the bristles 30 are planted is disposed in the cavity CA. The first molding surface 62 is formed with an opening 63 for positioning the bristles 30 planted in the head insert 20 outside the cavity CA. Around the opening 63, an insert support 64 having a stepped structure for stably supporting the surface side portion of the head insert 20 is formed.

The surface side portion of the head insert 20 is stably seated on the insert support 64. The insert support 64 extends from the first support surface 64a for supporting the surface edge portion of the head insert 20, and the first support surface 64a, and is a portion of the circumferential surface of the head insert 20 toward the surface. It is composed of a second support surface (64b) for supporting.

The first mold 61 is formed such that a bristle pocket (PO) for accommodating the bristles 30 positioned outside the cavity CA through the opening 63 therein communicates with the opening 63. The bristle pocket PO is disposed opposite the cavity CA with respect to the opening 63. According to the bristles pocket (PO) of this configuration, during a series of processes of molding the toothbrush head 11 to bury the head insert 20 in the inside of the toothbrush head 11, the bristles 30 are insert injection mold 60 ), because it is accommodated in the bristles pocket (see PO) provided in the outer area of the cavity CA, the bristles 30 can be safely protected from the outside, and the bristles 30 can be managed hygienically.

In order to mold the toothbrush holder 10, the head insert 20 is inserted into the insert injection mold 60. That is, the head insert 20, the surface of the head insert 20 is supported by the first support surface 64a, and the circumferential surface of the head insert 20 is supported by the second support surface 64b, 30) are arranged to be received in the bristle pocket PO through the opening 63. At this time, the movement of the head insert 20 is restricted by the restraining action of the first support surface 64a and the second support surface 64b. In addition, the bristles enter the bristle pocket PO and are positioned in a state that is spatially blocked from the outside of the insert injection mold 60 on the outside of the cavity CA within the insert injection mold 60.

Next, after combining the first mold 61 and the second mold 65, the molten resin is injected into the cavity CA through the gate of the insert injection mold 60 at a constant pressure, and the injected resin When cooled and cured, a toothbrush according to an embodiment of the present invention having a toothbrush head 11 in which the head insert 20 is buried is manufactured. Of course, the manufactured toothbrush is formed in a shape in which the insert groove 14 accommodates the rear portion of the head insert 20 in the toothbrush head 11, so that the surface side portion of the head insert 20 is the insert groove 14 ) Is formed in a shape protruding from the toothbrush head 11 through the inlet.

Here, the portion of the surface side of the head insert 20 protruding from the toothbrush head 11 through the entrance of the insert groove 14 where the surface and the circumferential surface meet is in contact with the gums, teeth, etc. It may be formed into a smooth curved surface by a round (round) treatment to prevent damage to the.

On the other hand, the head insert 20 is not coupled to the toothbrush head 11 by insert injection molding, but is inserted into the insert groove 14 of the separately molded toothbrush head 11, and then the toothbrush head 11 using ultrasonic waves. ) And the contact surface of the head insert 20 may be bonded to the toothbrush head 11.

According to the test results of the present inventors, in the case of fine hairs with a thickness of less than 0.07 mm, even if it is composed of a large bundle having a cross section corresponding to a large-area hair growth hole of 19 mm 2 or more, the fine hairs themselves are too soft, so when manufacturing with a toothbrush There was an ineffective problem in terms of cleaning. On the other hand, in the case of fine hairs exceeding the thickness of 0.14 mm (for example, 0.15 to 0.18 mm), if it is composed of a large bundle having a cross section corresponding to a large-area hair follicle hole of 19 mm2 or more, the fine hair when manufactured with a toothbrush Their cleaning power was excessively increased, so the degree of abrasion of the teeth during brushing was quite large and the degree of irritation of the gums was severe.

In addition, for fine hairs with a thickness of 0.07 to 0.14 mm, as a result of testing by varying the taper length of the taper portion, if the taper length is less than 3 mm, the elasticity of the taper portion is large as the taper length is short. There was a problem with severe gum irritation. On the other hand, if the tapered length exceeds 8 mm, the tapered portion is too soft and has weak elasticity, so even if the elasticity is improved by the heat treatment step, the elasticity of the tapered portion can be uniformly handled by the toothbrush manufacturing facility. As it was not improved to the level, bending and shaking occurred seriously in the process of taking out, transferring, and inserting by the hair insertion device, and the quality of the manufactured toothbrush was not constant.

Therefore, fine hairs planted in large-area hair transplanting holes of 19 ㎟ or more have a thickness of 0.07 to 0.14 mm and a taper length of 3 to 8 mm for a soft toothbrushing feeling, excellent cleaning power, improved durability of bristles, consistent quality, and improved productivity. It was preferable in terms of the like.

Meanwhile, the inventors tested the heating process in the heat treatment step as follows.

It was tested while changing and combining the heating time and the distance from the nozzle 40 of the hot air fan to the parent bundle together with the temperature and air volume in the range of 120 to 650°C and air volume 80 to 250 L/min. The wind direction was set so that the hot air was sprayed toward the end of the parent bundle in the longitudinal direction (straight direction) by using the nozzle 40 with 10% of the cross-sectional area A1 of the parent bundle.

As a result, when the hot air temperature is less than 200°C, the elasticity of the taper portion of the fine hairs is not improved, and when the hot air temperature exceeds 600°C, a change in physical properties occurs in the tapered portion of the fine hair. If the air volume is less than 100ℓ/min, it took a long time to improve the elasticity of the tapered portion, and when the air volume exceeded 200ℓ/min, there was a problem that the fine hairs were bent. The distance between the parent bundle and the nozzle 40 was preferably as close as possible in terms of maintaining temperature and air volume. If the heating time is less than 1 second, even if the hot air temperature is set high, the elasticity of the tapered portion is not improved, and if the heating time exceeds 12 seconds, a change in physical properties occurs in the tapered portion or the heating process takes a long time, which is not preferable.

Therefore, the heating process provides hot air in the longitudinal direction of the microhairs toward the end of the tapered portion of the microhairs, and at this time, the hot air temperature is 200 to 600°C, the air volume is 100 to 200 L/min, and the heating time is 1 to 12 seconds. It was desirable.

In the heat treatment step, the cooling process may use air cooling, water cooling, or a method using cold metal immediately after the heating process, but for the cooling process, in consideration of quality and productivity, in the cooling chamber at a temperature of -1 to -25°C for 1 to 30 minutes During the test was carried out.

As a result, the cooling effect was small at a temperature below -20°C, and it took a long time to cool. In order to give a meaningful cooling effect to improve the elasticity of the tapered portion of the fine hair, it was preferable to perform it for 5 to 10 minutes at a temperature of -20 °C or less in the cooling chamber.

Although the present invention has been described above, the present invention is not limited by the disclosed embodiments and the accompanying drawings, and may be variously modified by a person skilled in the art without departing from the technical spirit of the present invention. In addition, the technical idea described in the embodiment of the present invention may be implemented independently, or two or more may be implemented in combination with each other.

10: toothbrush stand
11: toothbrush head
20: head insert
21: large area hair transplant hole
22: small area hair transplant hole
30: brush head
31: first bristle (first fine hair)
32: second bristles (second fine hair)
33: tapered portion
34: base part

Claims (11)

Cutting a filament having a thickness of 0.07 to 0.14 mm;
Forming a tapered portion having a taper length of 3 to 8 mm on at least one or more of both ends of the cut filament;
Including the step of heat-treating the formed tapered portion to increase the crystallinity of the tapered portion,
How to make a brush head. The method according to claim 1,
The heat treatment is characterized in that heating for 1 to 12 seconds at a temperature of 200 to 600 °C and an air volume of 100 to 200 L/min using a hot air machine,
How to make a brush head. The method according to claim 2,
The heat treatment is characterized in that to provide hot air in the longitudinal direction of the filament cut toward the end of the tapered portion,
How to make a brush head. The method according to claim 2 or 3,
The heat treatment is characterized in that cooling after heating by using the hot air,
How to make a brush head. The method of claim 4,
The cooling is characterized in that performed for 5 to 10 minutes at a temperature of -20 °C or less in the cooling chamber,
How to make a brush head. Preparing a head insert in which at least one hair growth hole is formed with a large area of 19 mm 2 or more;
Preparing fine hairs having a thickness of 0.07 to 0.14 mm and a tapered length of 3 to 8 mm;
Heat-treating the tapered portions of the prepared fine hairs to increase crystallinity of the tapered portions;
Planting the heat-treated fine hairs into the large-area hair transplantation holes of the prepared head insert;
Including the step of coupling the head insert in which the fine hairs are planted to a toothbrush head,
How to make a toothbrush. The method of claim 6,
Prior to planting the fine hairs, characterized in that it further comprises the step of removing static electricity from the heat-treated fine hairs,
How to make a toothbrush. The method of claim 7,
The step of removing static electricity from the fine hairs is characterized in that injecting an ionized gas onto the heat-treated fine hairs,
How to make a toothbrush. Heat-treating the tapered portions of the fine hairs to increase the crystallinity of the tapered portions;
Transplanting the heat-treated fine hairs into the hair transplanting holes of the head insert;
Including the step of coupling the head insert in which the fine hairs are planted to a toothbrush head,
How to make a toothbrush. By manufacturing by the method according to claim 6,
A toothbrush head;
A head insert coupled to the toothbrush head and having at least one hair transplant hole having a large area of 19 mm 2 or more;
It is planted in the large-area hairdressing hole of the head insert, the thickness is 0.07 to 0.14 mm, the tapered length of the tapered part is 3 to 8 mm, and the tapered part includes fine hairs heat-treated,
toothbrush. The method of claim 10,
Some of the fine hairs are characterized in that at least one or more of a thickness and a tapered length are different,
toothbrush.

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