Cleaning element holder and toothbrush head comprising cleaning element holder

Abstract

A cleaning element holder (30) in the form of a tray for a toothbrush is disclosed wherein the rear surface (32) comprises a central recess (35) covering at least 70% of the rear surface (32) forming an edge (34) at a boundary, and wherein the front surface (31) comprises at least one protrusion (37) such that the front surface (31) comprises two horizontal portions, which are arranged in the central recess (35). Wherein the area covered by the recess (35) is larger than the area covered by the protrusion (37). Further disclosed is a manual toothbrush (14) or a replacement brush head (19) for a power toothbrush, comprising a cleaning element holder (30) as disclosed herein.

Description

[0001] This application is a divisional application of PCT patent application PCT / US2020 / 070146 (international application date is June 16, 2020, priority date is June 21, 2019, Chinese national application number is 202080045454.4, and the name of the invention is "Cleaning element holder and toothbrush head including a cleaning element holder") which entered the Chinese national stage on December 21, 2021. Technical Field

[0002] Modern brush heads (particularly toothbrush heads) have a high degree of design flexibility. Several requirements, such as deep cleaning, sensitive cleaning, gum massage, cleaning teeth with braces, etc. require different brush heads, including individual arrangements of different types of cleaning elements. In addition, consumers also require a good mouthfeel during brushing, which limits, for example, the size or thickness of the toothbrush head. Therefore, an improved manufacturing process is needed, which allows a high degree of design flexibility in order to meet all the requirements of a modern toothbrush. For example, different cleaning elements (such as elastomeric cleaning elements) and different types of bristle tufts must be securely arranged together at one brush head. The present invention relates to a cleaning element holder or a portion thereof for a (tooth) brush head, which allows the high variability of integrating different types of cleaning elements. Background Art

[0003] Methods for producing brush heads or parts thereof are known in the prior art. In most methods, fusing the ends of bristle tufts to form a fused ball is an important step. The resulting fused ball not only connects the bristle filaments of a bristle tuft to each other, but also helps to securely mount the bristle tuft in the brush head. Specifically, a fused ball that is larger than the bristle tuft can anchor the bristle tuft in the brush head.

[0004] One production method using this anchoring is the anchor-independent tufting (AFT) method developed by Bart G. Boucherie. Thus, the bristle tufts are pushed through the holes of a perforated plate, and the ends of the tufts that are not intended for cleaning are fused by applying heat energy. The fuse ball thus formed is larger than the hole, so that the bristle tufts are stuck at the back of the perforated plate. The fuse ball can also be combined with the perforated plate, for example, by applied heat energy or by ultrasonic welding; the perforated plate is then installed in the brush head together with the bristle tufts (EP1142505B1). The uniform size, form and shape of the fuse ball are not important for the AFT method.

[0005] In contrast, in the hot tufting method developed by Ulrich Zahoransky, the bristle tufts are arranged in the holes of the mold bar so that the fused ball can be used for overmolding with plastic material. During this overmolding, the brush head is at least partially formed and the bristle tuft and the formed brush head are combined. Since the fused ball is larger than the bristle tuft itself, an undercut is formed during the overmolding process, so that the bristle tuft and the brush head are firmly combined. The use of the hot tufting method can meet the geometric requirements of the brush head to be formed.

[0006] There is a constant need in toothbrush manufacturing to further increase the flexibility of brush head design. Therefore, different types of cleaning elements and different types of bristle tufts must be securely contained in one brush head. Summary of the invention

[0007] According to one aspect, a cleaning element holder in the form of a disc for a toothbrush is provided, the cleaning element holder comprising a front surface, a rear surface and a thickness, wherein the rear surface comprises a central recessed portion, the central recessed portion covers at least 70% of the rear surface and forms an edge at the boundary, and wherein the front surface comprises at least one protrusion, so that the front surface comprises two horizontal portions, wherein the area covered by the recessed portion is larger than the area covered by the protruding portion of the brush head, specifically a toothbrush head.

[0008] According to another aspect, there is provided a manual toothbrush or replacement brush head for an electric toothbrush comprising a cleaning element holder as disclosed herein.

[0009] According to another aspect, there is provided a cleaning element holder and a (tooth)brush head comprising such a cleaning element holder manufactured by the method as described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1A An exemplary embodiment of a cleaning element holder 30 having a central protrusion 37 is shown in side view;

[0011] Figure 1B An exemplary embodiment of a cleaning element holder 30 having a central protrusion 37 and a central depression 35 is shown in cross-section;

[0012] Figure 1C An exemplary embodiment of a cleaning element holder 30 having a central protrusion 37 including bristle tufts 20 is shown in side view;

[0013] Figure 1D shows a cross-sectional view of an exemplary embodiment of a cleaning element holder 30 having a central protrusion 37 and a central recess 35 including bristle tufts 20 arranged to a bristle field 28;

[0014] Figure 2A , Figure 2B The gap 38 ( Figure 2A ) of a cross-sectional view of an exemplary embodiment of a cleaning element holder 30, the voids may be filled with elastomeric cleaning elements 40 ( Figure 2B );

[0015] Figure 2C , Figure 2D A cross-sectional view of an exemplary embodiment of a cleaning element holder 30 is shown, the cleaning element holder including a drive feature 44 ( Figure 2C ), the driving part is firmly connected to the cleaning element support 30 through the cover 46 ( Figure 2D );

[0016] Figure 2E A cross-sectional view of an exemplary embodiment of a cleaning element holder 30 including a drive part 44, elastomeric cleaning elements 40, and bristle tufts 20 is shown;

[0017] Figure 3 a) to Figure 3 i) shows a schematic diagram of a method for producing a cleaning element holder 30;

[0018] Figure 4A , Figure 4B A manual toothbrush 14 ( Figure 4A ) and replacement brush heads 19 ( Figure 4B ), each of which includes a cleaning element holder 30 as disclosed herein;

[0019] Figure 5 A top view of a perforated plate 60 including three dies for forming cleaning element holders 30 is shown. DETAILED DESCRIPTION

[0020] The following is a description of many embodiments of methods for producing brush heads or parts thereof and brush heads or parts thereof produced by the methods disclosed herein. This description should be regarded as merely exemplary and does not describe every possible embodiment, since it is impractical, if not impossible, to describe every possible embodiment, and it should be understood that any feature, characteristic, structure, component, step or methodology described herein may be deleted, combined with or replaced by any other feature, characteristic, structure, component, product step or methodology described herein, in whole or in part. In addition, a single feature or (sub)combination of features may be inventive, regardless of the feature combination provided in the claims, the corresponding part of this specification or the drawings.

[0021] The unit "cm" used herein means centimeter. The unit "mm" used herein means millimeter. The unit "μm" or "micrometer" used herein means micrometer. The unit "mil" used herein means one thousandth of an inch.

[0022] As used herein, the word "about" means + / - 10%.

[0023] As used herein, the word "comprise" and its variations are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other similar items that may also be useful in the materials, devices, and methods of the present invention. The term includes "consisting of" and "consisting essentially of."

[0024] As used herein, the words "includes" and variations thereof are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other similar items that may also be useful in the materials, apparatus, and methods of the present invention.

[0025] As used herein, the words "preferred", "preferably" and their variations such as "especially" and "particularly" refer to embodiments of the present invention that provide particular benefits under particular circumstances. However, other embodiments may also be preferred under the same or other circumstances. In addition, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the present invention.

[0026] The present invention provides a method for producing a brush head (specifically a toothbrush head or parts thereof), the method comprising providing at least two bristle clusters, the at least two bristle clusters comprising a plurality of bristle filaments, wherein the at least two bristle clusters are different in at least one characteristic. As used herein, the term "bristle cluster" is understood to be any shape, form, size and / or arrangement of bristle filaments of predefined length. Bristle clusters can be formed by any geometric shape, form or arrangement produced by grouping each bristle filament. The standard shape given as an example is a circular bristle cluster, an elliptical bristle cluster, a sickle-shaped bristle cluster, a bristle cluster stripe or a combination thereof. In addition, two or more bristle clusters can be arranged in a cluster-in-cluster arrangement, wherein the shape of each individual cluster can be the same or different, and combined with the alternative scheme given above. For example, a circular cluster can be arranged in a circular cluster, or a circular cluster can be arranged in an elliptical cluster, or a striped cluster can be arranged in a circular cluster, etc. In a cluster-in-cluster arrangement, two clusters can be different in at least one characteristic, or can be the same with respect to at least one characteristic. At least two bristle clusters differing in at least one characteristic are arranged in a perforated plate comprising a front surface, a rear surface, a thickness and one or more holes, preferably a plurality of holes, wherein the one or more holes, preferably a plurality of holes are distributed in the perforated plate according to the desired bristle area of ​​the brush head or parts thereof to be produced.

[0027] The perforated plate will be disclosed in more detail below. In one embodiment, the perforated plate comprises a front surface, a rear surface, a thickness and one or more holes, preferably a plurality of holes, wherein the holes can be grouped into more than one arrangement of holes, wherein the more than one arrangement of the holes can be the same or different from each other, preferably the same or different from each other with respect to the number of holes, the shape of the holes, the size of the holes, the distance between the holes and their combination. This means that the perforated plate may include multiple arrangements of holes, wherein each arrangement corresponds to the desired bristle area of ​​the brush head to be produced or its parts, preferably in a circular or elongated form, more preferably in the form of the head of a manual toothbrush or a replacement brush head for an electric toothbrush. Alternatively, the perforated plate may include only one arrangement of holes corresponding to the desired bristle area. Preferably, the perforated plate includes the same arrangement of holes, more preferably, the perforated plate includes 4 identical arrangements of holes. In addition, more than one perforated plate (e.g., two perforated plates) may be combined into a larger perforated plate. The number of holes in one arrangement may be in the range of 1 to 60 holes, preferably 10 to 60 holes, more preferably 15 to 40 holes, more preferably 15 to 35 holes, more preferably 15 to 30 holes. The distance between adjacent holes in one arrangement is in the range of 0.2 mm to 2.0 mm, preferably in the range of 0.4 mm to 1.8 mm, more preferably in the range of 0.5 mm to 1.2 mm. The distance between adjacent arrangements in one perforated plate is defined by the design and the molding process used, and may be at least 2 mm, in particular in the range of 2 mm to 40 mm.

[0028] The shape of the hole in the perforated plate corresponds to the shape of the bristle tufts to be located in the corresponding hole. The bristle tufts can be manufactured in any form, wherein the form can be adjusted according to the function of the tufts, the position of the tufts in the bristle area, the form of the cleaning element support and / or their combination. During the positioning of the bristle tufts in the holes of the perforated plate, the bristle tufts adjust the shape of the holes and can be fixed in this shape in further processing steps (such as during fusion). The suitable shape of the hole of the perforated plate is circular, semicircular, sickle-shaped, elliptical, elongated, angled, for example, quadrilateral, trapezoid, pentagon, hexagon, heptagon, octagon or their mixture. All different shapes can be combined with each other, for example, a semicircular shape can be combined with a quadrilateral shape, or a trapezoidal shape can be combined with a sickle-shaped shape. The preferred hole of the perforated plate is circular, oval, semicircular, sickle-shaped, elongated or angled, more preferably circular or oval.

[0029] Additionally or alternatively, the size of the holes depends on the clusters to be integrated. Thus, the size of the holes may be about 0.6 mm. 2 To about 40mm 2 The appropriate size of the hole for a round standard bristle tuft is 0.6 mm. 2 Up to 3mm 2 In the range of 1.0 mm, preferably2 Up to 2mm 2 More preferably, it is about 1.5 mm 2 In addition or alternatively, the perforated plate may also include holes for bristle tufts having the size of multiple standard bristle tufts, specifically the size of 2 to 25 bristle tufts, more specifically the size of 2 to 15 bristle tufts, and more specifically the size of 5 to 10 bristle tufts. A preferred embodiment of a large tuft comprising the size of more than one standard tuft may be, for example, a block tuft comprising a combination of about 5 to 15 bristle tufts. Thus, a preferred range of holes for block tufts may be about 8 mm. 2 To about 24mm 2 More preferably, about 8 mm 2 To about 16mm 2 within the range.

[0030] The perforated plate to be used in the method as disclosed herein can be made of any suitable material that is resistant to the method steps as disclosed herein and can be formed. Heat-resistant materials are preferred because the perforated plate as disclosed herein is particularly used as a part of the mold. As used herein, suitable materials for the perforated plate are any heat-resistant material (specifically metals and metal alloys, such as steel, specifically stainless steel), heat-resistant plastics (specifically polytetrafluoroethylene (PTFE) or polyetheretherketone (PEEK)), ceramics or combinations thereof. The perforated plate can be produced by any method that allows the formation of high-precision parts (such as metal casting (specifically aluminum casting), 3D printing, vitrification, pulse electrochemical machining (PECM), molding). Depending on the manufacturing method used, the perforated plate can be a single component or a base component comprising several component parts. For example, the base component can be made of steel, including a cavity for an insert, including a hole arrangement as described above. Such an arrangement allows different bristle areas to be manufactured using one base component simply by changing the arrangement of the holes. In addition, the arrangement of holes that need to have high quality and high precision can be produced independently of the base component.

[0031] In a preferred embodiment, the perforated plate may include an uneven front surface, preferably an uneven front surface in the area of ​​the arrangement of the holes, more preferably, wherein the front surface in the area of ​​the arrangement of the holes is a convex surface. Therefore, one arrangement of holes may be located on different horizontal parts of the perforated plate. For example, the front surface may include protrusions in the area of ​​at least one arrangement of the holes, or the front surface may include one or more protrusions in the area of ​​each arrangement of the holes. In a preferred embodiment, the one or more protrusions in the front surface of the perforated plate are central protrusions. The central protrusion may include the area of ​​at least one hole and the area of ​​at most all holes of the perforated plate belonging to one bristle tuft arrangement. In addition or alternatively, one or more protrusions (specifically the central protrusion) may cover at least 10% of the area of ​​the front surface, preferably at least 15% of the area of ​​the front surface, more preferably at least 20% of the front surface. The central protrusion may protrude from the front surface by about 0.2 mm to about 0.6 mm, preferably from about 0.3 to about 0.5 mm, more preferably from about 0.35 mm to about 0.45 mm, and even more preferably the central protrusion protrudes from the front surface by about 0.4 mm.

[0032] According to the method as disclosed herein, the perforated plate as disclosed herein comprises through holes (i.e., holes) for the generation of bristle tufts, as long as the plate thickness and the bristle tufts can be repositioned in the holes and at different distances from the front surface of the perforated plate. In addition, the perforated plate may also comprise blind holes, wherein the blind holes may be used for elastomeric cleaning elements.

[0033] A suitable thickness of the perforated plate may be in the range of 5 mm to 20 mm, preferably 6 mm to 14 mm. Furthermore, the perforated plate may comprise more than one layer, in particular wherein the more than one layer may consist of different materials. Suitable materials for the first layer comprising the front surface are heat-resistant and allow the formation of high-precision holes, such as stainless steel. Suitable materials for the second layer may be less heat-resistant, such as plastic materials. Furthermore, the perforated plate may also be combined with a stop plate. Thus, the rear surface of the perforated plate may be combined with such a stop plate, wherein the stop plate may comprise a flat surface or may comprise protrusions corresponding in form and shape to the arrangement of the holes. The stop plate may be used, for example, to arrange the bristle tufts orthogonally in the holes, in particular for changing and / or repositioning the position of the bristle tufts in the holes of the perforated plate during different process steps.

[0034] At least one characteristic of at least two bristle tufts, which differs according to the method as disclosed herein, is selected from the size of the bristle tufts, the form of the bristle tufts, the position of the bristle tufts in the perforated plate and / or in the desired bristle area of ​​the brush head to be produced, the material of the bristle filaments, the color of the bristle filaments, the diameter and / or cross-section of the bristle filaments, the shape of the bristle filaments, additives present in the bristle filaments, or a combination thereof.

[0035] As used herein, the term "bristle field" shall refer to an arrangement of more than one bristle tuft, preferably a plurality of bristle tufts. Thus, the use of the term is independent of the location of the arrangement, for example, the bristle field may be arranged in a perforated plate, in a mold bar, in a portion of a brush head, in a brush head or in a toothbrush.

[0036] The bristle filaments may be monofilaments made of a plastic material, for example. Suitable plastic materials for the bristle filaments may be polyamide (PA), in particular nylon, polyamide 6.6, polyamide 6.10 or polyamide 6.12, polybutylene terephthalate (PBT), polyethylene terephthalate (PET) or mixtures thereof.

[0037] The circumference of the bristle filaments may be substantially circular, or the circumference may include one or more recesses (such as X-band bristle filaments) or may vary along the long axis of the bristle filaments. The diameter of the circular bristle filaments may be in the range of about 4 mils (0.1016 mm) to 9 mils (about 0,2286 mm), specifically in the range of about 4 mils (0.1016 mm) to about 7 mils (0.1778 mm), more specifically in the range of about 5 mils (0.127 mm) to about 6 mils (0.1524 mm), or any other range that is narrower and falls within the above-mentioned broader ranges, as if these narrower ranges are expressly stated herein.

[0038] In addition, ultra-fine bristle filaments are used in toothbrushes relative to standard bristle filaments having diameters as given above. Ultra-fine bristle filaments have a smaller diameter than standard bristle filaments and can behave like dental floss during normal brushing. The diameter of ultra-thin bristle filaments can range from about 2 mils (0.0508 mm) to about 4 mils (0.1016 mm), or any other range that is narrower and falls within the above-mentioned wider ranges, as if these narrower ranges are expressly stated herein. The production tolerance for bristle filament diameter is 10%.

[0039] In addition to bristle filaments with a substantially constant diameter, bristle filaments whose diameter decreases towards the end may also be used. These kinds of tapered bristle filaments are based on standard diameter bristle filaments whose ends are chemically tapered. Suitable tapered bristle filaments are provided by, for example, BBC (Korea).

[0040] In addition, bristle filaments including irregular diameters, i.e., including at least one recess, may be used. As understood herein, a "recess" in the circumference, diameter, cross-section, and / or volume of a bristle filament should mean any recess, cavity, slot, or other geometric recess that modifies the volume of the bristle filament. A bristle filament having at least one recess on its circumference may have one or more recesses along the circumference of the bristle filament. A suitable example of a bristle filament having at least one recess is an X-shaped bristle filament. The X-shaped bristle filament has four recesses and two lines of reflected symmetry, each line of reflected symmetry passing through two recesses opposite to each other. In addition, all four recesses may be identical. The angle of the X-shaped bristle filament may be in the range of about 40° to about 160°.

[0041] The length of bristle filaments depends on the intended use. Generally speaking, bristle filaments can have any suitable length for transportation, such as about 1300mm, and then cut into segments of desired length. The length of the bristle filaments in a toothbrush affects the bending force required for bending the bristle filaments. Therefore, the length of the bristle filaments can be used to realize the different stiffness of the bristle filaments in the bristle area of ​​the brush head. The typical length of the bristle filaments for a brush (particularly a toothbrush) can be in the range of about 5mm to about 20mm, specifically in the range of about 6mm to about 15mm, more specifically in the range of about 7mm to about 12mm, or in any narrower and other numerical ranges falling within the above-mentioned wider numerical ranges, just as these narrower numerical ranges are all clearly stated herein.

[0042] In addition, the bristle filament material may include additives, such as abrasives, coloring pigments, flavoring agents, etc., to provide indicator filaments. "Indicator filaments" as understood herein are any elements that are modified over time and / or used to indicate the state of the toothbrush. For example, the indicator element may change or wear its color over time and / or use. During use, the coloring on the outside of the material slowly fades to indicate the degree to which the bristle filaments are worn. Suitable additives for the bristle filaments of the bristle tufts are, for example, ultraviolet fluorescent (UV) brighteners, signal substances, such as indicator coloring pigments and / or abrasives. For example, abrasives such as kaolin and / or bristle filaments may be colored at the outer surface.

[0043] A plurality of bristle filaments are grouped to form a bristle tuft. As used herein, the term "bristle tuft" is understood to be any shape, form, size and / or arrangement of bristle filaments of predefined length. A bristle tuft can be formed by any geometric shape, form or arrangement produced by grouping individual bristle filaments. The standard shapes given as examples are circular bristle tufts, oval bristle tufts, sickle-shaped bristle tufts, bristle tuft stripes or a combination thereof. The filaments forming a suitable number of bristle tufts can be, for example, in the range of about 10 to about 80 filaments, or in the range of about 15 to about 60 filaments, or in the range of about 20 to about 50 filaments, or in any other numerical range that is narrower and falls within the above-mentioned wider numerical range, as these narrower numerical ranges are clearly stated herein.

[0044] After at least two bristle tufts are arranged in a perforated plate, an energy source (specifically a thermal energy source) is arranged at a predefined distance from the front surface of the perforated plate, so that the ends of the at least two bristle tufts and the energy source are arranged in non-contact. In addition, at least two bristle tufts are arranged in a fusion position, wherein the ends of at least two bristle tufts to be fused are arranged in the perforated plate at different distances from the front surface, resulting in different distances between the ends of the bristle tufts and the energy source, wherein the distance is adjusted according to at least one characteristic of the at least two bristle tufts. Due to the different distances, the ends of the bristle tufts will melt equally, although they provide at least one different characteristic. As used herein, the term "equally melted" shall refer to standardizing the fusion process of at least two different bristle tufts so that fused balls of similar form and shape are formed within the same fusion time.

[0045] After arranging the at least two bristle tufts in the fusion position, energy, in particular thermal energy, is supplied from an energy source to the ends of the at least two bristle tufts until a fusible ball is formed at the ends of the at least two bristle tufts.

[0046] The bristle filaments of a bristle tuft are connected to each other at the ends and form a fuse ball. As used herein, the term "fuse ball" should be understood as the molten filament material that connects the bristle filaments of a bristle tuft after the fusion process. The fuse ball can have any shape or form, including but not limited to a plane, a plane with a recessed portion, a plane with a concave surface, a plane with a convex surface, a mushroom head, a dome-shaped head, or a combination thereof. The size of the fuse ball is based on the requirements to be met. The two main requirements are to ensure that the cluster is firmly connected to the brush head (cluster retention), and that the individual filaments are firmly bonded to each other in accordance with government regulations (filament retention).

[0047] The formation of the fusible ball during the fusion process will now be described in more detail. As used herein, the term "fusion process" is understood to be the whole process of applying energy (specifically heat energy) from an energy source to the end of at least one bristle tuft so as to form a fusible ball at the end of the bristle tuft. A non-restrictive exemplary fusion process begins with applying energy to the end to be fused of the at least one bristle tuft. Thus, the ends of the bristle filaments soften, so that the ends of the bristle filaments of the bristle filaments located at the bristle tuft contour soften faster than the ends of the bristle filaments of the bristle filaments located in the middle of the bristle tuft. Without being limited by theory, it is believed that the bristle filaments located in the middle of the bristle tuft are shielded by the bristle filaments located outside the bristle tuft and are not affected by the energy applied by the energy source. After softening, the bristle filament material melts and begins to flow along the bristle filaments. Thus, the free space between the bristle filaments of a bristle tuft is filled with molten material. In addition, the molten material flows downward at the contour of the bristle tuft, and the contour of the bristle tuft at the end of the bristle tuft increases, so that the fuse ball at the end of the bristle tuft forms a protrusion. At this stage, the form of the fuse ball can be described as a plane with a central depression or a concave plane. If more heat energy is applied, more bristle tuft material melts and combines with the already formed fuse ball. As a result, the form of the fuse ball changes, and the molten material accumulates at the end of the bristle tuft, thereby forming a convex plane. If more heat energy is applied, the material that previously flowed downward at the contour will also accumulate at the top of the end of the bristle tuft, and eventually form a mushroom head or dome-shaped fuse ball. The fusion process can be interrupted at any time, specifically when the form and shape of the fusion ball meet the requirements of further use of the bristle tuft. The fusion process as described herein can be performed in a horizontal or vertical arrangement of a perforated plate including bristle tufts. A vertical arrangement may be preferred because vapor or steam that may be generated during the fusion process can be removed and will not accumulate at the surface of the energy source. In addition, the energy source will not deform during the fusion process.

[0048] According to the present disclosure, it is preferred to fuse at least until the ends of the bristle tufts are fully melted. As used herein, the term "fully melted" should be understood as applying energy (preferably thermal energy) to the ends of the bristle filaments until the material of the bristle filaments softens and melts, and the molten material forms any kind of fused ball as defined above.

[0049] The preferred form of the fuse ball according to the present invention is a plane, a plane with a depression (particularly a plane with a central depression), a concave plane, a slightly convex plane, a convex plane or a combination thereof. Preferably, the fuse ball has the form of a plane. Thus, the geometrical profile of the plane is defined by the geometrical profile of the bristle tufts, which is defined and fixed by the geometry and form of the holes in the perforated plate. For example, a circular bristle tuft will form a disc-shaped plane, an elliptical bristle tuft will form an elliptical plane, a sickle-shaped bristle tuft will form a sickle-shaped plane, and a bristle tuft stripe will form a plane in the form of a stripe.

[0050] In addition, the preferred profile of the plane is larger than the profile of the bristle tuft, so that the fuse ball forms a protrusion at the end of the bristle tuft. Specifically, the ratio of the profile of the fuse ball of the bristle tuft to the profile of the bristle tuft is at least 1.05:1, preferably at least 1.1:1, more preferably at least 1.2:1, and more preferably at least 1.3:1. In subsequent processes (such as molding of the brush head or its parts), the protrusion will form an undercut, so that the bristle tuft is firmly connected to the brush head or its parts.

[0051] The end of the bristle tuft opposite the fused ball represents the end intended to clean teeth. The ends of the bristles intended for cleaning can be cut to a special profile, can be tapered, can be rounded at the end and can be polished to provide a safe and comfortable bristle tuft that will not harm the soft tissue in the oral cavity.

[0052] According to the method as disclosed herein, the distance between the energy source (specifically a thermal energy source) and the end of the bristle tuft to be fused is adjusted according to the characteristics of the bristle tuft, such as the size of the bristle tuft, the form of the bristle tuft, the position of the bristle tuft in the perforated plate and / or in the desired bristle area of ​​the brush head to be produced, the material of the bristle filaments, the cross-section and / or diameter of the bristle filaments, the shape of the bristle filaments, the color of the bristle filaments, the additives present in the bristle filaments, or a combination thereof. All of these characteristics affect the energy intake, specifically the thermal energy intake of the bristle tufts, and therefore the fusion process of each bristle tuft. Therefore, the ends of the bristle tufts are arranged at different distances from the energy source in order to standardize the fusion process again.

[0053] A suitable distance from the energy source (e.g., thermal energy source) to the front surface of the perforated plate is in the range of 0.5 mm to 1 mm, preferably in the range of 0.5 mm to 4 mm. The bristle tufts protrude from the perforated plate, and the more the bristle tufts protrude from the perforated plate, the smaller the distance between the ends of the bristle tufts to be fused and the energy source.

[0054] As disclosed herein, these characteristics affect the melting of bristle tufts and the formation of fusible balls. For example, the position of the bristle tufts in the perforated plate and / or in the desired bristle zone of the brush head to be produced affects the fusion process. Without being bound by theory, it is believed that the bristle tufts arranged at the periphery of the bristle zone shield the bristle tufts arranged in the middle of the bristle zone. The more bristle tufts arranged around the present bristle tuft, the more heat energy is shielded. Therefore, if all bristle tufts in the bristle zone should be fused at the same time and the fusible balls should be similar, preferably formed substantially the same, the shielding effect can be balanced by reducing the distance between the ends of the bristle tufts and the energy source. For example, when multiple bristle tufts are arranged in a perforated plate in a fusion position, the distance between the energy source and the ends of the bristle tufts arranged in the middle of the multiple bristle tufts is shorter than the distance between the energy source and the ends of the bristle tufts arranged at the periphery of the multiple bristle tufts, preferably, the distance between the energy source and the ends of the bristle tufts arranged in the center of the multiple bristle tufts is the shortest.

[0055] Similar effects are also shown with respect to the size of the bristle tufts or the form of the bristle tufts. In larger bristle tufts, the central filaments are shielded from energy during the fusion process. This effect is further affected by the form of the bristle tufts, as the shielding effect of round bristle tufts is greater than that of elongated striped bristle tufts. Without being bound by theory, it is believed that the formation of a central depression in the plane during the formation of the fusible ball is based on the shielding of the inner bristle filaments by the outer bristle filaments. Therefore, larger bristle tufts and / or bristle tufts with larger cross-sections are arranged at a smaller distance from the energy source than smaller bristle tufts and / or bristle tufts with smaller cross-sections. According to the method disclosed herein, the distance between the energy source and the bristle tuft end of the bristle tuft decreases as the cross-section of the bristle tuft in the fusion position increases.

[0056] In addition or alternatively, the fusion process is also affected by the characteristics of the bristle filaments, such as the material, diameter, cross-section, shape, color of the bristle filaments or the presence of additional additives in the bristle filaments. For example, at the fusion position, the distance between the energy source (specifically a thermal energy source) and the end of the bristle tuft is adjusted according to the material of the bristle tuft, wherein preferably, the distance of the bristle tuft comprising bristle filaments made of polyamide (PA) (specifically nylon), polyamide 6.6, polyamide 6.10 or polyamide 6.12 is greater than the distance of the bristle tuft comprising filaments made of polybutylene terephthalate (PBT) or polyethylene terephthalate (PET).

[0057] Additionally or alternatively, the fusion process is also slightly affected by the color of the bristle filaments. For example, the distance between the energy source and the bristle tuft end of a bristle tuft comprising green bristle filaments can be selected to be greater than the distance between the energy source and the bristle tuft end of a bristle tuft comprising filaments of any other color.

[0058] In addition or alternatively, the fusion process may also be affected by the size of the bristle filaments, specifically, by the diameter and / or cross-section of the bristle filaments. Without being bound by theory, it is believed that, for example, smaller bristle filaments melt faster than larger bristle filaments, and / or X-shaped bristle filaments melt faster than round filaments. For example, according to the method disclosed herein, at the fusion position, the distance between the energy source (specifically a thermal energy source) and the bristle tuft end of a bristle tuft including bristle filaments with smaller diameters and / or cross-sections may be greater than the distance between the energy source and the bristle tuft end of a bristle tuft including bristle filaments with larger diameters and / or cross-sections, preferably wherein the distance may decrease with increasing bristle filament diameter and / or cross-section, more preferably wherein the distance may decrease from about 2 mils (0.0508 mm) to about 9 mils (0,2286 mm) of bristle filament diameter. Additionally or alternatively, in the fused position, the distance between the energy source and the tuft ends of bristle tufts comprising bristle filaments having an X-shaped diameter may be greater than the distance between the energy source and the tuft ends of bristle tufts comprising bristle filaments having a circular diameter.

[0059] Another characteristic that may affect the fusion process and therefore the fusion position of the bristle tuft is the presence or absence of an additive in the bristle filaments. The additive can slow down and / or speed up the fusion process by absorbing or reflecting thermal energy during use. For example, in the fusion position, the distance between the energy source (e.g., a thermal energy source) and the end of the bristle tuft including bristle filaments with an additive (e.g., clay or titanium dioxide) is shorter than the distance between the energy source and the end of the bristle tuft including filaments without the additive.

[0060] The influence of all the characteristics of the bristle tufts and bristle filaments as disclosed above can compensate for each other or can enhance each other. For example, a bristle tuft with a smaller cross-section located in the middle of the bristle zone can undergo a similar fusion process compared to a bristle tuft with a larger cross-section located outside the bristle zone. Therefore, according to the method as disclosed herein, all the characteristics of the bristle tuft are taken into account by adjusting the distance from the end of the bristle tuft to the energy source. Preferably, the influence of some characteristics is evaluated to be greater than the influence of other characteristics. In a preferred embodiment of the method as disclosed herein, the distance between the end of the bristle tuft and the energy source (e.g., a thermal energy source) is adjusted according to the size and / or cross-section of the bristle tuft, the position of the bristle tuft in the bristle zone, or a combination thereof, and more preferably, the distance between the end of the bristle tuft and the energy source (e.g., a thermal energy source) is adjusted according to the position of the bristle tuft in the bristle zone.

[0061] Any suitable energy source capable of producing the required amount of energy can be used for the fusion process as disclosed herein. For example, a thermal energy source can be used, which is a heater, preferably a convection heater, a thermal radiation heater, an infrared radiation lamp, etc. Alternatively, the heater can be a heating plate, more preferably, wherein the heating plate is at least partially made of a conductive material for emitting thermal radiation when an electric current flows through the conductive material. Suitable heating sources are disclosed, for example, in WO2015 / 094991A1, which is incorporated herein by reference. For example, the thermal energy source may include a heating plate, which is at least partially made of a conductive material for emitting thermal radiation when an electric current flows through the conductive material. The heating plate may be structured so that: at least two heating sections are formed, each of the at least two heating sections comprises a conductive material, the at least two heating sections are separated from each other by at least one separation section, and the at least one separation section is arranged to emit less thermal radiation than the heating section; and each heating section has a heating surface on the heating side of the heating plate, wherein each of the heating surfaces has a heating surface having a thickness between about 0.25 mm and a thickness between about 0.25 mm. 2 To about 250mm 2 In particular, at least one of the heating surfaces has an area of ​​less than 100 mm 2 area.

[0062] The heating surface may be heated to such an extent that the heat radiation is sufficient to melt the ends of the bristle tufts provided at a certain distance in the emission direction. During the fusion process, the distance between the ends of the bristle tufts and the heating surface may be in the range of about 0.05 mm and about 5 mm, preferably in the range of about 0.1 mm and about 2 mm, and is adjusted according to the characteristics of the bristle tufts as disclosed herein. The temperature of the heating surface may be in the range of about 500 degrees Celsius to about 800 degrees Celsius, and the application time of the heat energy from the heat energy source during fusion may be in the range of 1 second to 15 seconds, preferably 2 seconds to 12 seconds, more preferably 3 seconds to 10 seconds, more preferably 4 seconds to 8 seconds, more preferably 5 seconds to 7 seconds. A suitable heat energy (Φ) flow from the heat energy source to the ends of at least two bristle tufts located in the perforated plate, wherein the temperature in ° C measured with an emissivity of 0.88 is in the range of 500°C to 1000°C, preferably 600°C to 900°C, more preferably 650°C to 850°C.

[0063] The heating surface of the heating section of the heating plate may be made of an electrically conductive material having a higher electrical resistance than the electrical resistance of the electrically conductive material forming at least one separating section at least partially adjoining the heating section. For example, this may be a layer of electrically conductive material at the location of the heating section which is thinner than the layer thickness of the electrically conductive material at least partially forming the separating section, and / or this may be an electrically conductive material for achieving a higher resistivity of the heating section than the electrically conductive material at least partially forming the separating area. When sufficient current flows through the heating section (i.e. a current typically up to 200 amperes), sufficient heat radiation will be emitted. The layer thickness of the conductive material forming the heating section may be, for example, about or below 1.0 mm, in particular below 900 μm, below 800 μm, below 700 μm, below 600 μm, below 500 μm, below 400 μm, below 300 μm, below 200 μm, or below 100 μm, preferably in the range of 250 μm to 750 μm or in the range of about 400 μm to about 600 μm. The layer thickness of the conductive material in the separation section may be above 1.0 mm, in particular above 1.5 mm, above 2.0 mm, above 3.0 mm, above 4.0 mm, above 5.0 mm or above 10 mm.

[0064] As a heating zone, a structured part of the heating plate is understood herein to contain an electrically conductive material, which structured part has a heating surface on the heating side of the heating plate, which heating surface tends to emit a higher amount of thermal radiation than a surface area of ​​a separating section at least partially adjoining the respective at least two heating zones, in particular because the electrically conductive material contained in the heating zone has a higher electrical resistance than the electrically conductive material in adjacent (i.e. adjoining) areas of the heating plate, or because the heating zone is embedded in an insulating material.

[0065] Resistivity ρ (also known as resistivity, specific resistance, or volume resistivity) quantifies how strongly a given material opposes the flow of electric current. Low resistivity indicates that the material readily allows charge to move. For example, 18% chromium / 8% nickel austenitic stainless steel has a resistivity of ρ steel =6.9.10 -7 Ωm, copper has a resistivity of ρ copper =1.68·10 -8 Ωm, PET (polyethylene terephthalate) has a resistivity of ρ PET =1.0·10 21 Ωm (all values ​​are given for a temperature of 20°C). Resistivity is a material property. The resistance R of a section of resistive material of length l and cross-sectional area A to the flow of current between its ends in the direction of its length is given by R=ρl / A. Thus, the resistance of a section of uniform material of a given length can be increased by reducing its cross-sectional area, as is well known.

[0066] There is no perfect isolator material, however, "conductive material" shall mean a material with a resistivity lower than ρ = 1.0 Ωm (specifically, the limit may be set to be lower than ρ = 1.0·10 -1 Ωm), and “isolation material” shall mean a material with a resistivity higher than ρ=1.0 Ωm (specifically, the limit may be set to be higher than ρ=1.0·10 3 Ωm). Metals such as steel, copper, silver, gold, iron, and metal alloys (which allow free electron flow) are good conductive materials. Other conductive materials include amorphous carbon, conductive ceramics such as ITO, and conductive polymers such as PEDOT:PSS. Particularly suitable conductive materials within the scope of the present disclosure are those conductors that are thermally stable at temperatures of about 500 degrees Celsius to about 800 degrees Celsius as described above.

[0067] Within the meaning of the present disclosure, many metals such as steel, copper, aluminum, silver, many metal alloys including iron-based alloys or copper-based alloys such as brass, bronze or beryllium copper (ASTM B194, B196, B197), etc. are thermally stable (i.e., do not significantly deform or melt or otherwise degrade so that the material can be used for an industrially reasonable period of time). Good isolator materials are glass, paper, dry wood, Teflon, PET, hard rubber, rubbery polymers, isolating ceramics such as alumina or talc, and many plastics, etc.

[0068] Passing an electric current through a conductor releases thermal energy by a process known as resistive heating (or ohmic heating or Joule heating). The resistive heating results in the emission of thermal radiation (specifically, the emission of infrared radiation), which is absorbed by the ends of the filaments in an amount large enough to melt the thermoplastic material at the exposed ends of the bristle tufts and form a fused ball structure of the molten material, as has been discussed in detail previously. The fusing of the ends of the bristle tufts as disclosed herein can be performed horizontally (i.e., the tufts are arranged substantially parallel to the direction of the earth's gravity), but can also be performed vertically (i.e., where the tufts are substantially inclined relative to the direction of the earth's gravity, specifically where the tufts are arranged substantially perpendicular to the direction of the earth's gravity). Vertical fusion will be particularly possible if the applied thermal energy is suitable for the various characteristics of the bristle tufts as disclosed herein. The molten bristle tuft ends melt very quickly and also solidify very quickly when the source of thermal radiation is removed, so that substantially no "nose" of dripping plastic melt is produced. The fusion technique applies more thermal energy than is required to form the fused ball, thereby heating, for example, the entire environment, making it almost impossible to avoid at least the generation of the described nose during vertical fusion. Due to the limited heating of the ends of the bristle tufts as disclosed herein, the volume of material melted is lower than the volume during normal fusion, so the surface tension of the molten material is higher and the generation of a nose or even dripping material is effectively reduced. In addition, the cost of the heating process can be further optimized by using different heating sections so that the heating surface selectively emits different amounts of thermal radiation during operation of the device. The area of ​​the heating surface of each heating section in the heating sections can be about 0.25mm 2 and about 250mm 2 In the range of about 0.5 mm 2 and about 100mm 2 In the range of , the upper limit may be smaller, such as about 90 mm. 2 , 80mm 2 , 70mm 2 、60mm 2 , 50mm 2 , 40mm 2 , 30mm 2 , 20mm 2 , 10mm 2 , 5mm 2 , 4mm 2 , 3mm 2 or 2mm 2 Typical cylindrical clusters, such as those used in many toothbrushes today, may have a diameter in the range of between about 0.5 mm and about 2.5 mm, specifically between about 1.0 mm and about 2.0 mm, and further specifically between about 1.3 mm and about 1.8 mm. As an example, a circular cluster with a diameter of 1 mm has a diameter of about 0.785 mm.2 Some toothbrushes include large-sized single tufts, such as the Oral-B Toothbrush with large single bristle tuft at the front end, approximately 28mm in area 2 (30mm 2 can be considered as an appropriate upper limit). Obviously, even larger single bristle tufts (50 mm 2 The distance between adjacent tufts of the toothbrush is preferably within the range of about 0.2 mm to about 5.0 mm, and more preferably within the range of about 0.5 mm to about 2.0 mm. In some current toothbrushes, a distance between adjacent tufts of about 0.8 mm to about 1.6 mm is used.

[0069] Higher heat emission of the heating surface can be achieved by having a different average profile roughness Ra on the heating surface than on the adjacent surface of the separation segment made of conductive material. Typical values ​​of the average profile roughness of the heating surface are Ra ≥ 20 μm, specifically Ra ≥ 25 μm (an upper limit of Ra ≤ 200 μm, specifically Ra ≤ 200 μm, and further specifically Ra ≤ 50 μm can be adopted). Typical values ​​of the average profile roughness of the surface of the separation segment are Ra ≤ 10 μm, specifically Ra ≤ 5 μm, and further specifically Ra ≤ 2.0 μm. A typical polished surface has an average profile roughness of Ra ≤ 1.0 μm (where fine grinding results in an average profile roughness of Ra ≤ 0.2 μm).

[0070] The heating surface may be a non-planar surface, for example may be concavely formed, so that the heat radiation will be more concentrated than a planar heating surface. Generally speaking, the heating plate may be made of a sintered material, in particular a laser sintered material, in particular an electrically conductive material, even though the heating plate may also comprise an insulating material.

[0071] After forming the fuse ball, at least two bristle tufts are transferred to a subsequent process position, wherein at the subsequent process position, the distance from the bottom edge of the fuse ball of at least one bristle tuft to the front surface of the perforated plate is different from the distance from the bottom edge of the fuse ball of the bristle tuft to the front surface of the perforated plate at the fusion position, wherein the subsequent process position may be, for example, a molding position. Preferably, at the fusion position, the distance between the bottom edge of the fuse ball and the front surface of the perforated plate of at least one bristle tuft is greater or less than (preferably greater than) the distance between the bottom edge of the fuse ball and the front surface of the perforated plate of the at least one bristle tuft at the subsequent process position. As used herein, the term "bottom edge of the fuse ball" should be understood as a position at the bristle filaments in the bristle tuft at which the change in the bristle filament material (i.e., the softening or melting of the bristle filament material) caused by energy (specifically, thermal energy applied during the fusion process) ends.

[0072] This means that after the fusion process, the position of the bristle tuft in the perforated plate can be revised again, wherein the position of the bristle tuft is adjusted according to the requirement of the subsequent process. For example, in the fusion position, the distance between the bottom edge of the fuse ball and the front surface of the perforated plate of at least one bristle tuft is greater than or less than the distance between the bottom edge of the fuse ball and the front surface of the perforated plate of at least one bristle tuft in the subsequent process position. For example, the subsequent process may be the overlapping injection molding of the fuse ball to at least partially form a brush head. If the subsequent process position is adjusted according to the molding process, the larger distance between the bottom edge of the fuse ball and the front surface of the perforated plate may be advantageous, so that more material flows around the fuse ball and the bristle tuft is more closely fixed in the brush head to be formed. In addition or alternatively, the smaller distance between the bottom edge of the fuse ball and the front surface of the perforated plate may be advantageous, so as to produce a small brush head and / or generate free space in the brush head above the fuse ball. This free space may be required to include other features of a toothbrush head, such as a transmission device or a coupling element required for the toothbrush head of an elastomer cleaning element or an electric toothbrush. In the molding position, the suitable distance between the bottom edge of the end of the bristle tuft and the front surface of the perforated plate of at least two bristle tufts is in the range of 0.2 to 3 mm, preferably 0.3 to 2.5 mm, more preferably 0.4 to 2 mm, more preferably 0.5 to 1.5 mm, more preferably 0.6 to 1.2 mm.

[0073] Other subsequent process steps (such as viewing or inspection steps and / or molding steps) of providing the elastomeric cleaning elements into the perforated plate may optionally be included in the method as disclosed herein. Suitable viewing or inspection steps may include inspecting and confirming the correct number, diameter and / or color of the filaments in each hole of the perforated plate; inspecting and confirming the correct position of the bristle tufts and / or elastomeric elements in the holes of the perforated plate; inspecting the presence and quality of the fuse balls of the bristle tufts and / or their combinations. The quality inspection of the fuse balls may include displacing the fuse balls from the perforated plate so that the fuse balls can be visually inspected through top, bottom and side views to check the form and size of the fuse balls and whether all filaments are completely included. Finally, the bristle tufts are arranged in a molding position, wherein the distance between the bottom edge of the fuse ball and the front surface of the perforated plate is adjusted according to the requirements of the subsequent molding process, wherein according to the method as disclosed herein, the molding position of at least one bristle tuft is different from the fusion position of the bristle tuft.

[0074] After the bristle tufts are arranged in the molding position, the fuse balls of at least two bristle tufts are overlap-molded with a plastic material to form a brush head or parts thereof. Thus, a mold is formed in which a perforated plate forms a part of the mold. The mold is formed so that the fuse ball is located in a hollow portion formed by the mold without contacting any inner surface of the mold, so that when the brush head or parts thereof are formed, the fuse ball can be embedded in the material to be fully injected. Suitable materials for forming the brush head or parts thereof are hard plastic materials. The Shore D hardness of a "hard plastic" material as understood herein can be in the range of about 30 to about 90, specifically in the range of about 40 to about 80, more specifically in the range of about 50 to about 80, and even more specifically in the range of about 65 to about 75. Suitable materials that can be used as the hard plastic material may be, for example, polypropylene (PP), polyethylene (PE), polyoxymethylene (POM), polyethylene terephthalate (PET), polyamide (PA), or a blend or mixture containing polypropylene (PP), polyethylene (PE), polyoxymethylene (POM), polyethylene terephthalate (PET) or polyamide (PA).

[0075] The brush head may include additional elements, such as chemical release elements or elastomeric elements. As understood herein, a "chemical release element" is any element that releases chemicals after contact with water and / or saliva during use and / or mechanically affected by the bristle tuft filaments during brushing. Suitable chemical release elements are, for example, pads or reservoirs filled with or including chemically active substances. Suitable chemically active substances that can be released can be, for example, anti-allergic chemicals, analgesic chemicals, wound healing chemicals, anti-inflammatory chemicals, flavoring components, anti-tartar chemicals, whitening chemicals, antibacterial agents, anti-corrosion chemicals or mixtures thereof.

[0076] As understood herein, "elastomeric element" is any cleaning element that is not a bristle filament or a bristle tuft. The elastomeric element can be formed, for example, by a soft plastic material. The Shore A hardness of the "soft plastic" material as understood herein can be in the range of about 10 to about 80, specifically in the range of about 20 to about 70, more specifically in the range of about 30 to about 60, even more specifically in the range of about 30 to about 40. The Shore A hardness of the soft plastic material is suitable for the geometry of the elastic element. Compared with thicker elements, thinner geometric elements can be made of materials with a larger Shore A hardness, and vice versa. The selection of soft plastic material also depends on the length of the formed element. In principle, longer geometric elements can be made of a soft plastic material with a larger Shore A hardness compared to shorter elements. Suitable materials that can be used as soft plastic materials can be, for example, rubber, thermoplastic elastomer (TPE), polyethylene (PE), polypropylene (PP), polyoxymethylene (POM) or their blends or mixtures. Materials exhibiting elastomeric properties, such as TPE are preferably used as the soft plastic material herein. The soft plastic material can have any geometric form, such as knobs, pins, fins, walls, rods, grooves, bends, round pieces, sheets, textured elements, polishing elements such as, for example, polishing cups, or tongue scraping elements, or combinations thereof.

[0077] Elastomeric element can be produced before bristle tuft and / or can be provided with bristle tuft, and can be overmolded with the material for forming brush head or its parts.In addition or alternatively, brush head or its parts can include holes, and these holes are filled with elastomeric material in subsequent processes to form elastomeric element.Preferably, the elastomeric element included in the bristle zone is produced and / or provided before bristle tuft and / or with bristle tuft.In addition or alternatively, the elastomeric element (for example, the element that is intended to clean gum line or tongue) positioned at the profile of brush head and / or the back side of brush head is preferably produced and / or provided after bristle zone.Independent of the process step used, physical connection is established between elastomeric element and brush head.Toothbrush can be for example manual toothbrush or the replacement brush for electric toothbrush, and this electric toothbrush includes brush head, handle and the neck that brush head and handle are connected to each other as disclosed herein providing one or more cleaning elements, and wherein one or more cleaning elements can include one or more elastomeric elements and one or more bristle tufts. The method disclosed herein allows a high degree of design flexibility and makes the handling of non-bristle tuft cleaning elements as easy as bristle tuft cleaning elements. The handling of elastomeric elements is generally challenging because elastomeric elements are difficult to grip, may be strongly affected by electrostatic forces, and are difficult to handle due to their elastomeric properties. If the elastomeric elements are formed directly in the perforated plate, these handling problems are reduced. By the method disclosed herein, bristle tuft cleaning elements and elastomeric elements are handled in a similar manner, thereby making toothbrush manufacturing more efficient. In addition or alternatively, the present method can also easily handle advanced filament types, such as ultra-thin filaments that are chemically or mechanically tapered in anchor-independent manufacturing techniques.

[0078] After the expected cleaning elements are all placed in the perforated plate, a mold cavity is formed, which includes a perforated plate as the first half mold and at least one second half mold. The plastic material forming the brush head or its parts is then injected into the mold cavity. Thus, the fuse ball of one or more bristle tufts and the optional elastomeric element molten plastic material are overmolded. Thus, the fuse ball is embedded in the plastic material and forms an undercut so that the bristle tuft is fixed against the pulling force. For example, the molten material of the cleaning material support can flow around the tuft end of the bristle tuft to form a bead or plate, or any geometric protrusion of the elastomeric element can be embedded in the molten material to form a brush head or its parts. Preferably, the part formed by the molten material is a cleaning element support. The cleaning element support includes a front surface, a rear surface and a thickness, wherein the cleaning element support is at least thick enough to embed one or more fuse balls fully in the cleaning element support. The suitable thickness of the cleaning element support can be in the range of about 2.0mm to 4.0mm, preferably in the range of 2.2mm to 4.0mm, more preferably in the range of 2.5mm to 3.5mm. The bristle filaments protrude from the front surface of the cleaning element support, and at least two fusible balls are preferably located at different horizontal parts in the cleaning element support. The cleaning element support can be made of any suitable plastic material, specifically any plastic material that can be processed in a molten state. Suitable materials include polyethylene (PE), polypropylene (PP), polyoxymethylene (POM), thermoplastic elastomer (TPE) or blends or mixtures thereof, wherein different materials exhibit different advantages and are selected accordingly. For example, polyoxymethylene is a harder material that exhibits higher resistance during use, but is more difficult to process during injection molding; in contrast, polypropylene has poor hardness and tolerance, but is also cheaper and easier to process during injection molding. In the present invention, the material of the cleaning element support is preferably made of polypropylene.

[0079] The cleaning element support may also include an edge at the periphery of the rear surface. This means that the cleaning element support may also include a central depression in the rear surface, preferably in the range of 0.1mm to 3mm, more preferably in the range of 0.5mm to 2.5mm, more preferably in the range of 1mm to 2mm, more preferably in the range of 1.5 to 1.8mm. The central depression may cover at least 70% of the area of ​​the rear surface, preferably at least 80% of the area of ​​the rear surface, more preferably at least 85% of the area of ​​the rear surface, more preferably at least 90% of the area of ​​the rear surface, more preferably 90% to 98% of the area of ​​the rear surface. For example, the drive part may be located in the first central depression. In addition, the cleaning element support may also include a second central depression in the rear surface, wherein the optional second central depression is preferably in the range of 0.1mm to 2mm, more preferably in the range of 0.1mm to 1.6mm, more preferably in the range of 0.2mm to 0.8mm. The second recessed portion (particularly the second central recessed portion) may cover at least 30% of the area of ​​the first recessed portion, preferably at least 40% of the area of ​​the first recessed portion, more preferably 40% to 50% of the area of ​​the first recessed portion. For example, a distribution channel or a soft plastic material layer for soft plastic cleaning elements may be located in the second central recessed portion.

[0080] In addition or alternatively, the cover can be located inside the edge and can cover the recessed portion of the cleaning element support, wherein the surface of the cover preferably forms a flat surface with the edge of the cleaning element support. The cover can be produced separately, and it can also be directly molded onto the cleaning element support, for example, by injection molding. For example, the material of the cover can include polyethylene (PE), polypropylene (PP), polyoxymethylene (POM), thermoplastic elastomer (TPE) or their blends or mixtures. The material can be molten and can be directly injected into the cleaning element support. Preferably, the material of the cover can be the same as the material used for the cleaning element support. If both materials are the same, then the best bonding is obtained between the cleaning element support and the cover. Preferably, polypropylene (PP) is used as the material of the cover. In an alternative preferred embodiment, the elastomer cleaning element and the cover are made of the same material, specifically made of thermoplastic elastomer (TPE). The color of the material of the cover can be the same or different from the color of the material of the cleaning element support.

[0081] In addition or alternatively, the cleaning element support may include one or more slots, which are suitable for receiving one or more elastomeric elements. The slot may have any geometry and shape, and the form and shape of one or more slots may be adjusted according to the form and shape of the elastomeric element. If more elastomeric elements are included in the cleaning element support, the elastomeric elements may be identical to each other or may be different in form and shape. If more elastomeric elements made of the same material are included in the cleaning element support, the rear surface of the cleaning element support may include a distribution channel, which connects one or more slots to each other so that the elastomeric material can be distributed on the cleaning element support and all elastomeric elements can be produced in a process step. This means that the elastomeric elements are connected to each other by the elastomeric material located in the distribution channel. In contrast, different elastomeric elements may be produced independently of each other. Suitable materials that can be used for elastomeric elements include a blend of rubber, thermoplastic elastomer (TPE) or their mixture, preferably using a thermoplastic elastomer (TPE) material.

[0082] The cleaning element support including bristle tufts and optional elastomeric elements represents a central part, i.e., a cleaning part of a toothbrush head. The cleaning element support may be included in a toothbrush head for a replacement brush head for an electric toothbrush, or may be included in a toothbrush head for a manual toothbrush. For example, the cleaning element support may be placed in a mold and may be overmolded with a molten plastic material to form a toothbrush, a replacement brush head for an electric toothbrush, or a part thereof. This means that a brush head (particularly a toothbrush head or its parts) and a toothbrush including the toothbrush head or its parts preferably produced by a method as disclosed herein may be used to manufacture any kind of manual toothbrush or any kind of electric toothbrush replacement brush. Therefore, the present disclosure also provides a brush (particularly a toothbrush) comprising a cleaning element support, which provides a cleaning element as disclosed herein.

[0083] A detailed description of several exemplary embodiments will be given below. It should be noted that all features described in the present disclosure, whether they are disclosed in the more general embodiments described above or in the exemplary embodiments of the device described below, or even they may be described in the context of a specific embodiment, are of course disclosed as individual features that can be combined with all other disclosed features, as long as this will not conflict with the purpose and scope of the present disclosure. Specifically, all features disclosed for any one of the devices or a part thereof or disclosed together with the method can also be combined with other parts or a part thereof of the device (if applicable) and / or applied to other parts or a part thereof of the device, and vice versa.

[0084] Figure 1AAn exemplary embodiment of a cleaning element holder 30 is shown. The cleaning element holder 30 comprises a front surface 31, a rear surface 32 and a thickness T. Suitable thicknesses of the cleaning element holder 30 as disclosed herein are in the range of 2.5 mm to 3.5 mm. The cleaning element holder 30 shown in FIG. 1 is a disk, but non-circular shapes are also possible. The cleaning element holder 30 comprises at least one protrusion 37, wherein the protrusion 37 is centrally located at the front surface 31. The central protrusion 37 covers at least 10% of the entire front surface 31, preferably 15% of the entire front surface, and more preferably 20% of the entire front surface 31. The size of the central protrusion 37 as a percentage of the entire front surface 31 depends on the cluster design. The central protrusion 37 protrudes about 0.4 mm from the front surface 31. The central protrusion 37 preferably terminates between two clusters, but in certain embodiments, the central protrusion 37 may also terminate in one or more clusters.

[0085] Figure 1B Another exemplary embodiment of a cleaning element holder 30 is shown, which includes a front surface 31, a rear surface 32, and a thickness T. Suitable thicknesses for cleaning element holders 30 as disclosed herein are in the range of 2.5 mm to 3.5 mm. Cleaning element holder 30 includes: at least one protrusion 37, which is centrally located at the front surface 31; and a central recessed portion, which is located at the rear surface 32. The central recessed portion 35 covers at least 70% of the rear surface 32, so that an edge 34 is formed in the periphery. The edge 34 can be about 0.6 mm to 1.2 mm thick, but smaller edges are also possible, as long as a stable edge is formed during the manufacturing process. The central protrusion 37 covers at least 10% of the entire front surface 31, preferably 15% of the entire front surface, and more preferably 20% of the entire front surface 31.

[0086] Figure 1C An exemplary embodiment of a part 10 of a brush head is shown. The part 10 shown in the side view comprises a cleaning element holder 30 having a front surface 31 and a rear surface 32 and a plurality of bristle tufts 20. Seven bristle tufts 20 can be seen, each of which comprises a plurality of filaments 22. The bristle tufts 20 protrude from the front surface 31 of the cleaning element holder 30, and the ends 26 of the filaments 22 intended for cleaning are rounded at the ends to ensure economical use. At the opposite ends of the filaments 22, a fusible ball (not shown) is formed, which is embedded in the cleaning element holder 30. The part 10 of the brush head also comprises two elastomeric cleaning elements 40 made of thermoplastic elastomer (TPE).

[0087] Figure 1DA cross-sectional view of another exemplary embodiment of a part 10 of a brush head is shown, the brush head including a cleaning element holder 30 having a plurality of bristle tufts 20 forming a bristle field 28. Three different types of bristle tufts 20 (20a, 20b, 20c) are shown, which may differ in the number, color, length and / or material of the individual filaments. The bristle tuft 20c is a cluster-in-cluster embodiment, wherein the inner center tuft protrudes from the peripheral tufts. The cleaning element holder 30 includes: at least one protrusion 37, the at least one protrusion being centrally located at the front surface 31; and a central recessed portion, the central recessed portion being located at the rear surface 32. The bristle tufts 20 protrude from the front surface 31 of the cleaning element holder 30, and the formation of the filaments is intended for the ends 26 of the bristle tufts 20 for cleaning to be rounded at the ends to ensure economical use. A fuse ball 24 is formed at the opposite ends of the bristle tufts 20, which is firmly embedded in the cleaning element holder 30. The rear surface 32 of the cleaning element holder 30 includes a central recess 35, wherein the central recess 35 covers at least 70% of the rear surface 32, so that an edge 34 is formed in the periphery. The edge 34 may be about 0.6 mm thick, but smaller edges are also possible, as long as a stable edge is formed during the manufacturing process. The front surface 31 includes a central protrusion 37, wherein the area of ​​the cleaning element holder covered by the protrusion 37 is smaller than the area of ​​the cleaning element holder covered by the recess 35, so that the user of the brush head cannot identify the protrusion 37. The protrusion 37 may cover at least 10% of the front surface 31 and may help to locally increase the thickness T of the cleaning element holder 30. The standard thickness T of the cleaning element holder 30 in the periphery is in the range of 2.5 mm to 3.5 mm, wherein the central recess 35 may reduce the thickness by about 1.5 mm. Therefore, it may be advantageous to increase the thickness T again by the protrusion 37 at the front surface 31. The thickness T increased by the protrusion 37 may be about 0.4 mm, and may help to firmly embed the bristle tuft 20 in the middle of the cleaning element holder 30 .

[0088] Figure 2A A cross-sectional view of an exemplary embodiment of a cleaning element holder 30 including a void 38 that can be filled with cleaning elements is shown. The front surface 31 of the cleaning element holder 30 includes a central protrusion 37 that covers at least 20% of the front surface 31. The rear surface 32 of the cleaning element holder 30 includes a central recess 35 that covers at least 70% of the rear surface 32 to form an edge 34 in the periphery. A second recess 36 is shown in the middle of the central recess 35 that covers about 10% of the rear surface 32. Figure 2AThe cleaning element holder 30 shown is a disk, but non-circular shapes are also possible. The rear surface 32 also includes a network of grooves 39 connected to each other and located in the area of ​​the recessed portion 35. The grooves 39 can form any network suitable for connecting the voids 38, so that at each end of the grooves 39, a void 38 is located in the cleaning element holder 30, which void can be filled with a cleaning element. Figure 2B Shows Figure 2A The cleaning element holder 30 is shown with the voids 38 filled with elastomeric cleaning elements 40. The elastomeric material for the elastomeric cleaning elements 40 is added to the grooves 39 and distributed over the network so that the elastomeric connections 39a are formed therein and all the elastomeric cleaning elements 40 are formed together. Thus, the elastomeric cleaning elements 40 are connected to each other at the rear surface 32 of the cleaning element holder 30 via the elastomeric connections 39a.

[0089] Figure 2C A cross-sectional view of an exemplary embodiment of a cleaning element holder 30 is shown, which includes a central recess 35 at the rear surface 32 and a central protrusion 37 at the front surface 31. A drive feature 44 is disposed in the central recess. Figure 2D Shows Figure 2C , wherein the driving part 44 is mounted to the cleaning element holder 30 with a cover 46. The cover 46 is located inside the central recess 35, wherein the rear surface 47 of the cover 46 forms a flat surface with the edge 34. The material of the cover 46 is selected from polyethylene (PE), polypropylene (PP), polyoxymethylene (POM) or a blend or mixture thereof, preferably the material of the cover 46 is the same as the material of the cleaning element holder 30, and the cover 46 is directly formed into the recess 35 of the cleaning element holder 30 by injection molding. Therefore, the cover 46 and the cleaning element holder 30 are connected to each other, and the driving part 44 is firmly mounted. The color of the cover 46 is preferably different from the color of the cleaning element holder 30.

[0090] Figure 2CA cross-sectional view of an exemplary embodiment of a cleaning element holder 30 is shown, the cleaning element holder including a central recess 35 at the rear surface 32 and a central protrusion 37 at the front surface 31. The standard thickness T of the cleaning element holder 30 in the periphery is in the range of 2.5 mm to 3.5 mm, wherein the central recess 35 reduces the thickness by about 1.5 mm. The drive part 44 is placed in the central recess and covered with a cover 46. The cover 46 is located inside the central recess 35, wherein the rear surface 47 of the cover 46 forms a flat surface with the edge 34. The cover 46 is preferably made of the same material as the cleaning element holder 30, and the cover 46 is formed by direct injection molding into the recess 35 of the cleaning element holder 30. Several bristle tufts 20 and elastomeric cleaning elements 40 protrude from the front surface 31 of the cleaning element holder. Seven bristle tufts 20 can be seen, wherein each bristle tuft 20 is different from the other bristle tufts 20 in at least one characteristic. For example, the bristle tufts 20a and 20b differ in the position of the bristle tufts 20 in the cleaning element holder 30. The central bristle tuft 20c includes more bristle filaments and is a cluster-in-cluster embodiment that includes an inner cluster protruding from a peripheral cluster. In addition, the bristle filaments of the bristle tufts 20a, 20b, 20c may also differ in the material, color, or size of the bristle tufts. The elastomeric cleaning element 40 is made of a thermoplastic elastomer (TPE).

[0091] Figure 3 An illustrative method that may be used to produce a cleaning element holder 30 as disclosed herein is shown. Figure 3 A shows a side view of a perforated plate 60 comprising a front surface 61, a rear surface 62, a thickness D and a plurality of holes 70, wherein the plurality of holes 70 are shaped and distributed in the perforated plate 60 according to the desired bristle field 28 of the brush head to be produced. The thickness D is adapted to the length ( Figure 3 B). Thus, the perforated plate 60 is thick enough so that the filaments 22 of the bristle tufts 20 are stabilized and protected during the manufacturing steps, but thin enough so that the bristle tufts 20 can still be handled. A suitable thickness D of the perforated plate 60 is 6 mm to 14 mm. The holes 70 are adapted to the size and shape of the bristle tufts 20 that should be placed therein. For example, the bristle tufts 20a are larger than the bristle tufts 20b, so the holes 70 are correspondingly different.

[0092] exist Figure 3In C, the perforated plate 60 is rotated 90°. The bristle tufts 20 protrude from both sides of the perforated plate 60. One end 26 of the bristle tuft 20 is intended for cleaning and is therefore rounded at the end and includes a smooth surface. The opposite end 23 of the bristle tuft 20 is intended for fusing. The fusing of the end 23 is performed using a thermal energy source 80 close to the end 23. Due to the different characteristics of the bristle tufts 20a, 20b, the end 23 melts differently, i.e., different amounts of thermal energy are required to melt. For example, the bristle tuft 20a is significantly larger than the bristle tuft 20b, so that the bristle tuft 20a requires more thermal energy to melt. Therefore, the distance between the end 23 of the bristle tuft 20a and the thermal energy source 80 is smaller than the distance between the end 23 of the bristle tuft 20b and the thermal energy source 80. If thermal energy is applied, the end 23 melts and forms a fused ball 24 ( Figure 3 d), the fuse balls are similar to each other due to the different distances from the thermal energy source 80. Thus, the distance from the bottom edge 25 of the fuse ball 24 of the first bristle tuft 20a to the front surface 61 is different from the distance from the bottom edge 25 of the fuse ball 24 of the second bristle tuft 20b to the front surface 61. For example, the bristle tuft 20b located in the middle of the bristle area is not affected by the thermal energy from the thermal energy source 80 by its adjacent bristle tufts 20. Therefore, the bristle tuft 20b is arranged closer to the thermal energy source 80.

[0093] After forming the fuse ball 24, the bristle tufts 20 are arranged in the perforated plate 60 according to the arrangement of the bristle tufts 20 in the bristle area 28 to be produced. Figure 3 e). This means that during fusion, the distance between the fusible ball 24 and the perforated plate 60 can be different from the distance during subsequent process steps such as molding. The position of the bristle tufts 20 in the perforated plate 60 in the molding position is based on the position of the end 26 intended for cleaning in the bristle area 28. The perforated plate 60 represents a part of the mold and, together with the second mold half 82, provides a mold for the cleaning element holder 30. Then, the molten material (e.g. polyethylene) is filled into the mold and the cleaning element holder 30 ( Figure 3 f) wherein the fuse ball 24 is embedded in the material of the cleaning element holder 30 and is thus securely mounted thereto.

[0094] Figure 3 g to Figure 3 h shows an alternative embodiment in which the drive part 44 is further integrated into the cleaning element holder 30. Thus, the driver 44 is partially placed in the mold so that the molten polyethylene material surrounds the fuse ball 24 and a portion of the drive part 44. Figure 3 FIG. 1 shows an alternative embodiment in which the perforated plate 60 comprises a central depression 63. This central depression 63 will form a central protrusion 37 in the cleaning element holder 30 to be formed.

[0095] Figure 4AA schematic cross-sectional view of a manual toothbrush 14 is shown comprising a handle 13 and a head 12, wherein the head 12 comprises a cleaning element holder 30 as disclosed herein. The cleaning element holder 30 comprises a number of bristle tufts 20, wherein the bristle tufts 20 are each secured in the cleaning element holder 30 with a fused ball 24 and projecting from an end 26 intended for cleaning.

[0096] Figure 4B A schematic cross-sectional view of a replacement brush head 19 for an electric toothbrush is shown, comprising a neck 17 and a head 16. The head 16 comprises a cleaning element holder 30 as disclosed herein, as well as a drive part 44 and a gear connection 18. The cleaning element holder 30 comprises a number of bristle tufts 20, wherein the bristle tufts 20 are each secured in the cleaning element holder 30 with a fused ball 24 and projecting from an end 26 intended for cleaning.

[0097] Figure 5 A schematic top view of the front surface 61 of a perforated plate 60 comprising three arrangements 65 of holes 70 is shown. The arrangements 65 are separated from each other by a distance of at least 2 mm. The holes 70 in the arrangement 65 correspond to and are positioned according to the bristle zone 28 to be formed. Different sizes and shapes of the holes 70 are possible, for example, elongated holes 70a, elliptical holes 70b, circular holes 70c, arc holes 70d or trapezoidal holes 70e are shown, but other shapes or sizes may also be present depending on the bristle tufts to be used. The perforated plate 60 also includes some blind holes 64 suitable for receiving additional cleaning elements (such as elastomeric cleaning elements). More or less than the three arrangements 65 shown may be present in one perforated plate 60. Two or more perforated plates 60 may be combined into a larger whole.

[0098] The dimensions and values ​​disclosed herein are not to be understood as being strictly limited to the exact numerical values ​​cited. Instead, unless otherwise indicated, each such dimension is intended to represent the stated value and a functionally equivalent range around that value. For example, a dimension disclosed as "40 mm" is intended to mean "about 40 mm".

Claims

1. A cleaning element holder (30) in the form of a disc for a toothbrush, the cleaning element holder (30) comprising a front surface (31), a rear surface (32) and a thickness (T), The rear surface (32) comprises a central depression (35), which covers at least 70% of the rear surface (32) and forms an edge (34) at the boundary, and the front surface (31) comprises at least one protrusion (37), so that the front surface (31) comprises two levels, wherein the area covered by the depression (35) is greater than the area covered by the protrusion (37), and the rear surface (32) comprises at least one groove (39) in the area of ​​the depression (35), preferably a regular network of grooves (39) connected to each other, more preferably an X-shaped network of grooves (39) connected to each other.

2. A cleaning element holder (30) according to the preceding claim, wherein the difference in level at the front surface (31) is in the range of 0.2 to 0.6 mm, preferably 0.3 to 0.5 mm, more preferably 0.35 to 0.45 mm, more preferably about 0.4 mm.

3. A cleaning element holder (30) according to any one of the preceding claims, wherein the front surface (31) comprises at least one cleaning element, preferably cleaning elements of different types, more preferably bristle tufts (20) of different types.

4. A cleaning element holder (30) according to the preceding claim, wherein the at least one protrusion (37) is located in the center or in the periphery, preferably wherein one protrusion (37) is located in the center and more than one protrusion (37) is located in the periphery, more preferably wherein the at least one protrusion (37) comprises one or more bristle tufts (20).

5. The cleaning element holder (30) according to any one of the two preceding claims, wherein the at least one cleaning element is embedded in the cleaning element holder (30).

6. A cleaning element holder (30) according to any one of the preceding claims, wherein the central protrusion (37) at the front surface (31) covers at least 10% of the front surface (31), preferably at least 15% of the front surface (31), and more preferably at least 20% of the front surface (31).

7. A cleaning element holder (30) according to any one of the preceding claims, wherein the recess (35) at the rear surface (32) is in the range of 0.1 mm to 3 mm, preferably 0.5 mm to 2.5 mm, more preferably 1.0 mm to 2.0 mm and most preferably 1.5 mm to 1.8 mm.

8. A cleaning element support (30) according to the preceding claim, wherein the cleaning element support (30) comprises at least one gap (38), preferably wherein the at least one gap (38) is located at the end of the at least one groove (39), more preferably one of the gaps (38) is located at each end of the grooves (39) of the network, more preferably one of the gaps (38) is located at each end of the X-shaped network.

9. A cleaning element holder (30) according to the preceding claim, wherein at least one of the gaps (38) comprises a non-bristle tuft cleaning element, preferably an elastic cleaning element (40), more preferably wherein all gaps (38) comprise non-bristle tuft cleaning elements of the same material, more preferably wherein all gaps (38) comprise elastic cleaning elements (40) of the same material, and most preferably wherein all gaps (38) comprise cleaning elements made of a thermoplastic elastomer (TPE).

10. The cleaning element support (30) according to any one of the preceding claims, wherein the thickness (T) of the cleaning element support (30) at the border is in the range of 2.0 mm to 4.0 mm, preferably in the range of 2.2 mm to 4.0 mm, more preferably in the range of 2.5 mm to 3.5 mm.

11. A cleaning element holder (30) according to any one of the preceding claims, wherein the recessed portion (35) of the rear surface (32) is suitable for contacting a drive part (44), a driver, a bearing, a toothbrush handle (13) or a part thereof, a connecting element, and the connecting element can be connected to the drive part (44), the driver, the bearing, the toothbrush handle (13) or a part thereof; preferably, wherein the recessed portion (35) of the rear surface (32) is connected to the drive part (44), the driver, the bearing, the toothbrush handle (13) or a part thereof, a connecting element, and the connecting element can be connected to the drive part (44), the driver, the bearing, the toothbrush handle (13) or a part thereof; more preferably, wherein the recessed portion (35) of the rear surface (32) is connected to the connecting element, and the connecting element is connected to the drive part (44), the driver, the bearing or a part thereof.

12. The cleaning element holder (30) according to the preceding claim, wherein the cleaning element holder (30), the connecting element and / or the toothbrush handle (13) are made of polypropylene (PP), preferably wherein the cleaning element holder (30) and the connecting element or the cleaning element holder (30) and the toothbrush handle (13) are made of polypropylene (PP) of different colors.

13. A cleaning element holder (30) according to any one of the preceding two claims, wherein the drive part (44), the driver, the bearing or parts thereof are made of a plastic material having a Shore D hardness in the range of 60 to 100, preferably in the range of 70 to 90, more preferably in the range of 75 to 85, more preferably wherein the drive part, the driver, the bearing or parts thereof are made of polyoxymethylene (POM).

14. The cleaning element holder (30) according to any one of the preceding claims, wherein the cleaning element holder (30) is part of a replacement brush head (19) for an electric toothbrush or a manual toothbrush (14).

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