HK1082393B - Toothbrush and method for producing the same - Google Patents

Description

Toothbrush and method of manufacturing the same

Technical Field

The invention relates to a toothbrush and a manufacturing method thereof.

Background

Manufacturing toothbrushes according to the AFT (anchor Free Tufting) process has many advantages compared to the conventional bristle tying process of inserting bent bristles into the head portion of a toothbrush around anchors or clips. Almost any bristle setting can be achieved with the AFT process, since the shape of the tufts is not determined by the size of the corresponding fastener. In the ATF process, a support plate is used with a plurality of slits through which the tufts pass, and then the rear end is melted and permanently attached to the support plate. AFT processes are described, for example, in EP-A0972464, EP-A0405204 or EP-A0567672. The bristle embedded holder plate is then attached to the head portion of the toothbrush. Ultrasonic welding is preferred, and is described, for example, in DE-U20006311.

The AFT process allows different bristle contours to be produced in a simple manner by forcing bristles loosely through the gap into the desired contour shape using a template before melting. The properties of the toothbrush or its bristles, such as stiffness, wear, cleaning efficiency, however, depend on the length and positioning angle of the bristles, in addition to material selection and contour shape. Heretofore, these parameters, particularly bristle length and profile shape, could not be varied to further optimize dentifrice performance.

WO 94/22346 discloses a toothbrush having a bend in the bristle-carrying head portion, but does not describe the method of manufacture. The conventional bristle-embedding manner of such a toothbrush is rather complicated, since it is only possible to compensate for height differences in the head part by a balancing movement of the blocking means.

Disclosure of Invention

It is therefore an object of the present invention to provide a toothbrush which is simple to produce and requires little choice of bristle parameters in order to improve the cleaning efficiency. Furthermore, a corresponding production method is proposed.

According to a first aspect of the present invention there is provided a toothbrush comprising: a head portion having a front face and a rear face; at least one seat member connected to the head portion, wherein the at least one seat member is made of a hard plastic material and a soft plastic material and has a top surface, a back surface, and a plurality of gaps extending between the top surface and the back surface of the seat member, and wherein a welding edge made of a hard plastic material is provided on the back surface of the seat member; and a bundle of bristles directed through the aperture, wherein the bristles have rear ends that are melted to form a coating that at least partially covers the back face of the at least one seating element. Wherein the at least one carrier element to which the bristle tufts are secured is connected to the head portion such that a back face of the at least one carrier element is spaced from a front face of the head portion, thereby forming a cavity beneath the at least one carrier element. In addition, the at least one abutment element is at least partially elastically deformable relative to the head portion such that the front face exhibits a non-planar spatial conformation at least during use.

According to a second aspect of the present invention, there is provided a method of making the toothbrush described above, comprising the steps of: making at least one seat element from a hard plastic material and a soft plastic material; introducing bristles through the aperture into the at least one carrier element and using a heating die to melt the rear ends of the bristles for connection with the carrier element; connecting the at least one carrier element, to which the bristles are fastened, to the head part of the toothbrush such that the top surface which defines the front of the head part exhibits a non-planar spatial configuration at least when used as intended.

Advantageous refinements of the invention emerge from the description and from the drawings.

The invention is based on a toothbrush made by the AFT method. The toothbrush has a head part and at least one carrier element connected thereto, which has a plurality of slots through which the bristle filaments are guided and which is fixed to the carrier element by melting at its rear end. A surface of the at least one stand-off element holder defines a front face of the fabricated head portion. That is, the base of the bristles and possibly the face of the other cleaning element. According to the invention, the front face has a spatial shape differing from a plane and/or can assume such a shape when used as intended. By a suitable choice of the surface shape, i.e. the shape of the front face at rest and/or under load, which is different from a plane, a plurality of bristle fields can be produced. In particular, the length and the angle of orientation of the bristles relative to the actual plane of the head part can be easily varied.

The present invention may be implemented in different ways to provide a toothbrush with such static and/or dynamic surface shapes.

A first solution is to use a flexible carrier element, which is made, for example, of a thin, hard material or at least partially of a soft material, so that it has a certain form or material elasticity. Such an abutment element is preferably flat before being fitted into the head part, so that the tufting can be carried out in a simple manner. The heated die used to melt the bristle ends can produce the desired surface shape of the hard material, which can additionally be shaped by the bristle melt. Alternatively, in the case of a partially soft elastic carrier element, the surface shape is then formed only when the head part is inserted or when it is used, wherein a flat shape is also present in the resting state.

In the case of a soft component of the support element, the bristles are held at least in some regions by the elastic material and thus form a flexible support. In order to achieve sufficient flexibility, it is preferable to select: an elastomeric material having a shore a hardness of less than 70, a support plate having a thickness of less than 4 mm and a molten material having a layer thickness of less than 1 mm. Preferably, the surface shape is selected to be flat or convex in the transverse and/or longitudinal direction of the head portion so as to produce a surface shape change in use.

The advantages of the two-component carrier element are: the hard component facilitates ultrasonic welding and anchors the bristles, while the soft component provides the desired elasticity or deformability.

As hard materials, particularly suitable materials for making the head portion are: polyethylene (PE), polypropylene (PP), PET, Acrylonitrile Butadiene Styrene (ABS), Styrene Acrylonitrile (SAN). As soft material, a specially produced thermoplastic elastomer is preferably used, for example TPE, TPU, rubber, silicone. When the abutment element is two-component, such soft material matches the above-mentioned hard material, so that a non-detachable connection is produced.

Another solution for the toothbrush according to the invention is to use a rigid carrier element, the surface of which already has the desired surface shape. The back surface can be contoured to follow the curve of the surface. Alternatively, the surface is flat, so that the abutment elements have different thicknesses. The first variant has advantages in terms of material consumption and cooling time, but the AFT mold must match the shape of the back side. While a second variant makes it possible to use a conventional heating die with a flat front.

Another solution for the toothbrush according to the invention is to use a plurality of carrier elements, in which case the carrier elements can also have a flat surface. The required surface shape is predefined by the shape of the head portion and/or the shape of the abutment element, in particular by the position and orientation of the area prepared for mounting the abutment element. According to the invention, the abutment elements can be mounted at different heights and/or in different orientations. The different bristle areas are preferably realized in the form of building blocks from a plurality of elements without the need to make new carrier plates separately. The carrier element can be simultaneously tufted in the AFT machine, i.e. in one operation as an integral bristle field. Furthermore, regions with a soft elastic component, for example flexible regions or tooth cleaning elements, can be mounted between the carrier elements.

The seat member is preferably connected to the head portion using ultrasonic welding. In order to ensure a perfect weld between the two parts, the welding surfaces preferably lie in one plane. The desired surface shape is preferably only formed in the region delimited by the soldering surface. For example, a circumferential welding edge is formed in the edge region of the rear side, which welding edge interacts with a corresponding counter surface on the head part. If this cannot be done, for example because the support element has a step or another abrupt change in shape, welding can be dispensed with in these regions in a targeted manner. But at least 25% of the theoretically possible welding surface on the periphery of the head part is preferably used.

The same material is preferably used for the carrier element or its hard component and the head part. The two parts preferably consist of a material with little steps, i.e. no edges or grooves within the manufacturing tolerances. In practice, however, it is often not possible to avoid the formation of recesses at the interface, in which recesses deposits may form. In order for the user to be visually imperceptible of such deposits, the head part and the abutment element should preferably have different colors.

In a development of the invention, the material of the carrier element comprises additives such as taste or smell materials, temperature indicators, antibacterial substances, etc. Such additives are relatively expensive and are therefore preferably not used in the entire head part, including the handle, but only in the actual target area of the carrier element, i.e. in the region of the oral cavity when used as intended.

Drawings

Embodiments of the invention are illustrated in the drawings and described below. The attached drawings show that:

FIGS. 1a-c a toothbrush according to the invention with a rigid curved carrier element;

fig. 2a + b a toothbrush with a resiliently curved carrier element;

fig. 3a + b a toothbrush with a carrier element with an undulating surface;

figures 4a, b a toothbrush with a stepped support element;

FIG. 5a + b a toothbrush with two carrier elements and a boss therebetween;

fig. 6a + b a toothbrush with a three-part carrier element;

FIG. 7 is a toothbrush with a carrier element having a plateau-like elevated region;

figures 8a + b a toothbrush with a carrier element having an undulating surface;

fig. 9a + b a toothbrush with three carrier elements;

FIG. 10 is a toothbrush with an angled carrier element;

FIG. 11 a head portion for a toothbrush with three carrier elements;

FIG. 12a + b a toothbrush with a carrier element consisting of a soft component and a hard component;

FIGS. 13a-c, 14 are toothbrushes with a curved carrier element and bristles movable relative thereto;

FIGS. 15a-d, 16a-c are toothbrushes with a support element comprising a lattice-like hard component;

fig. 17 shows a toothbrush with a carrier element which is only connected in a point-like manner.

Detailed Description

All the toothbrushes shown in the figures have a handle, not shown, a head part 1 and at least one carrier element 2 connected or connectable thereto, which is filled with tufts 3 according to the AFT method. The front face 5 of the head part is formed so as to be approximately congruent with the surface 4 thereof in the case of only one carrier element 2 (see fig. 1 to 4, 6 to 8, 10, 12 to 16). according to the invention, in the rest state and/or in the use state, the front face 5 has a shape which differs from a plane, is curved inwards in fig. 1, i.e. in the direction of the head part 1, is curved outwards in fig. 2, 12 to 14, 16, is wavy in fig. 3 and 8, is flat in fig. 15, but is resilient, and has an inflection or a step in the remaining figures. Thus, by appropriate choice of the bristle length, different bristle contours 14, 15 with different stiffness of the tufts 3 can be produced in the longitudinal and transverse directions with respect to the head portion 1.

The carrier element 2 has a number of slots 6 for receiving tufts 3, which extend between the carrier element surface 4 and its rear surface 8. The angle of positioning of tufts 3 can be adjusted by the orientation of these holes 6. However, from a manufacturing process point of view, the holes 6 should preferably extend in the direction normal to the surface 4. The rear ends 3a of the tufts 3 are fixed to the carrier element 2 by melting with a heating die 12 (see fig. 1c), so that a coating 11 of bristles is produced. A further cleaning element 19 (see fig. 5a, b) made of a soft elastic material can be provided, which is preferably produced by two-component injection moulding during the manufacture of the carrier element 2 before the bristles. Even if the carrier element 2 itself is made of a soft material and a hard material, it should preferably be manufactured by means of two-component injection moulding.

The carrier element 2 has, in addition to the area 2a actually carrying the bristles, a preferably annular edge portion 9 projecting from its rear face 8. The edge portion serves on the one hand for centering when it is inserted into a correspondingly adapted recess 7 in the head portion 1 and on the other hand for realizing a welding surface 10, 10' for ultrasonic welding. The edge 9 also serves as a lateral limiting plate for the bristle melt 11.

In the case of the toothbrush shown in fig. 1a, b, the carrier element 2 is made of a hard material which is largely rigid and is arched in the longitudinal and transverse directions already before being inserted into the head part 1. The upper and lower faces 4, 8 of which extend parallel to each other. The material thickness is preferably less than 5 mm, in particular less than 3 mm. The bristles all have the same length and so form bristle contours 14, 15 that are concave in the longitudinal and transverse directions, following the curve of the surface 4 or front face 5.

As shown in fig. 1c, the tufts 3 are first inserted into the slots 6 of the carrier element. The bristle ends 3a are melted by a heating die 12, the upper side 13 of which is adapted to the curvature of the rear side 8 of the carrier element, so that the bristle coating 11 is formed. In the case of a profiled heating die, the bristle melt is preferably completely of equal thickness. The abutment element 2 and the head portion are then joined by ultrasonic welding. For this purpose, the face 2a projects laterally beyond the edge portion. The projection 2b thus formed rests on a projection 7b of the recess 7 when inserted into the head part 1, wherein the contact surface can be used as a welding surface 10. Furthermore, the lower end 9a of the edge portion 9 can also be used as a welding surface 10' together with the bottom 7a of the groove 7. For this purpose, the parts 2b and/or 9a can have a sharp edge 31 (see fig. 1c, 15a, 16a), which is used as a concentrator and as a reservoir for the material to be liquefied during the welding process.

In the example shown in fig. 2a, b, the carrier element 2 or its bristle-carrying surface 2a is made of a thin, hard material as much as possible. In the state without bristles embedded, the support element is flat and can be easily embedded with bristles. During the bristle setting, the bristles are introduced into the illustrated arched mold by means of the heating mold and engage in the recesses 7, so that they are arched outward in the transverse direction and fan the tufts 3 apart from one another. This results in a longitudinally flush and laterally convex bristle contour 14 or 15. Tests have shown that the bristle melt 11 adapts to the new surface shape without breaking. The abutment element 2 is then connected to the head portion 1. In order to avoid material incompatibility during ultrasonic welding, the edge portion 9 is preferably made of a hard component.

Alternatively, the carrier element 2 can also be made of a soft, elastic or thin, hard material which is sufficiently flexible to be inserted into the head part under prestress and upward curvature after the bristle has been installed in the flat state. For this purpose, the material thickness of the hard material is preferably at most 3 mm. The deformable portion of the support plate is pre-stressed by deformation so that the flexibility present in this region in use can be determined substantially together by the manufacture of the toothbrush.

Fig. 3a shows a toothbrush with a rigid carrier element 2 in longitudinal section, the surface 4 of which is corrugated and the rear side 8 of which is flat. The bristle-bearing face 2a preferably has a thickness of between a minimum of 3 mm and a maximum of 10 mm. Although all tufts 3 themselves have the same basic length, their free length varies from the root 3c on the surface 4 to their front end 3b due to the height profile of the plate 2a, so that different elastic properties of the bristles are achieved. The angle of the slot 6 and thus the angle of orientation of the bristles is also changed. Bristle plates with different free bristle lengths and contour shapes can be produced easily with such a carrier element, wherein a conventional flat AFT heating die can be used.

Fig. 3b shows a variant of the example in fig. 3a in cross section, in which the curve of the lower side 8 matches that of the upper side 4. This has the advantage of saving material and of reducing cycle time during the production of the carrier element 2 due to the faster cooling, but a heating die adapted to the lower face 8 must be used.

The toothbrush shown in fig. 4a, b has a carrier element 2, i.e. its bristle-carrying surface 2a has a step 17 on the surface 4 and the underside 8. The bristle contour 14 follows the curve of the surface 4 or the front face 5 in the longitudinal direction. In turn, the surface 10 below the surface 2a or the surface 10 'at the bottom of the groove described in connection with fig. 1 can be considered as a welding surface, the latter being advantageous because a continuous welding surface 10' can be formed as a result of the flat bottom 7 a. On the other hand, the abrupt surface shape change 17 in the welding surface 10 is a non-welding portion. The contour of the bristle ends and the front face 5 is arched outwards in the transverse direction (fig. 4b), corresponding to the section in fig. 2 b.

Fig. 5a, b show a toothbrush with two carrier elements 2 which are arranged in two recesses 7 on both sides of a raised area 18 in the center of the head part 1. This results in a front face 5 with two different levels. As already mentioned, the fastening of the carrier element 2 is effected by ultrasonic welding along a welding surface 10 on the edge of the carrier element 2, which welding surface is located outside the bristle field in top view (fig. 5 b). It is also possible to weld the faces only at the periphery of the head portion 1, while the faces 10 "adjoining the elevated regions 18 remain unwelded. Sufficient fixing can be achieved by welding of at least 25% of the possible contact surfaces. The lack of welding of the face 10 "allows some flexibility of the toothbrush, particularly when the elevated regions 18 are formed of an elastomeric material, so that the bristle head is partially deflected resiliently during use.

A soft, elastic tooth cleaning element 19 is arranged on the raised area 18. Outside the raised area 18, there are also further cleaning elements 20, which are also particularly soft and elastic. The head part 1 with these elements and the elastic regions that may be present are produced by two-component injection molding. The elevated region 18 can also be realized by a further support plate which, for example in the example of fig. 9a, b, fits into a common recess 7 with a precise fit with the other two support elements 2.

Fig. 6a, b show a similar toothbrush, but in which the central elevated region 18 is realized by a carrier element 2 having a stepped height profile. The height profile is narrower in the increased middle region 18, to which the shape of the groove 7 is adapted. If the welding is carried out below the edge 2b of the carrier element 2 and in the edge region of the elevated region 18, the welding surface 10 extends in two horizontal planes. There is no weld at the protruding portion 17. Alternatively, welding is performed along the face 10' at the bottom 7a of the groove 7.

Figs. 7a, b show yet another toothbrush with an intermediate raised area 18. The carrier element 2 has a central opening which can be covered by the elevated region 18. The abutment element 2 is welded to the head portion 1 along the hole and at its outer edge, whereby additional reinforcement is achieved. On the carrier element 2, tufts 3 and soft elastic elements 20 are arranged.

The carrier element 2 of the toothbrush shown in fig. 8a, b is corrugated in the longitudinal and transverse directions, so that a correspondingly structured front face 5 is formed. The bristle-carrying surface 2a is also curved at the edges, so that the contact surface and the welding surface 10 are likewise curved. Alternatively, the welding (welding surface 10') can be performed in one plane of the bottom 7 a.

Fig. 9a, b show a toothbrush with two different levels, which is realized by three separate carrier elements 2, the edge portions 9 of which have different lengths L, L'. These carrier elements are inserted into three recesses 7 separated by connecting strips 30 or into a common recess (not shown) and are welded at their base 7a (welding surface 10'). Alternatively, the welding can also be carried out below the respective bristle-carrying surface 2a at the two horizontal surfaces 10. The central carrier element 2 comprises both conventional bristles and a soft, elastic cleaning element 19.

Fig. 10 shows a toothbrush with an inflected support element 2. Also as in the other examples, the shape of the head portion 1 or the recess 7 here is chosen such that: the edge of the bristle-carrying surface 2a is connected flush with the head part, i.e. the upper surface 1a of the head part 1 likewise has an inflected curve. Here, two anchoring zones with edge portions 9 and correspondingly two matching recesses 7 are provided. Alternatively, the inflected front face 5 can also be realized by two separate support plates adjoining at the inflections 29, wherein a flexible region in the region of the inflections 29 can additionally be provided in the head part 1.

Fig. 11 shows a head part 1 for a toothbrush with three carrier elements 2. For the purpose of inserting these support elements, three recesses 7 are provided, between which individual recesses a transverse strip 30 is provided, in particular made of a soft elastic material. Welding is performed only on the periphery of the head portion 1 along the line 10. The front face can be designed, for example, as shown in fig. 9.

Fig. 12a, b show a toothbrush with a carrier element 2 which comprises a soft component and a hard component. The actual bristle-carrying part 2a of the carrier element 2 consists of a soft material 21, which is elastically deformable. The bristles are elastically suspended or anchored. The pillow-like portion 21 flexes under load, which is particularly advantageous for protecting teeth. To facilitate the connection with the head section 1, the carrier element 2 has on its periphery a rim section 22, preferably made of the same hard material as the head section. An upward arching occurs during the production of the carrier element 2. The lower edge of the frame part 22 lies flat against the corresponding projection 7b of the recess 7 of the head part 1, wherein the contact surface defines the welding surface 10. The cavity between the lower face 8 of the seating element 2 and the bottom 7a of the recess 7 allows, in use, a certain deflection of the elastic portion 21, in some cases even a reversal from the convex state to the concave state.

Fig. 13a to c and 14 show a carrier element or head part of a toothbrush in which the rear ends 3a of the tufts 3 are not fixedly welded to the bristle-carrying face 2a, but rather the tufts can be pushed into the holes 6. This is achieved by a suitable choice of material, for example by polypropylene for the carrier element and polyamide for the bristle filaments. Furthermore, the rear end 3a is not melted to form a uniform bristle coating, but rather is melted by a heating die 12 having projections 23 to form spaced apart connecting strips 24 of bristle solution. For elastic support of the tufts 3, a layer of elastic membrane 25 is provided in the head portion. In the case of fig. 13c, the membrane is arranged in a recess 7 and is introduced before the mounting of the carrier element 2. In the case of fig. 14, the film forms one outer surface of the head portion. The film is injection molded when the head portion is made. The melted rear end 3a of the bristle mould is pressed upwards by the membrane, so that the bristle-bearing face 2a is arched upwards like a pillow.

Fig. 15a to d and 16a to c show a toothbrush with a two-component carrier element 2. The support element comprises a grid-like hard component, here formed by a sleeve 26 with holes 6 for receiving the tufts and a connecting strip 27 connecting said sleeve. Furthermore, a frame part 22 made of a hard component is provided. In the case of use, the edge of the frame part facing the bottom is designed to be sharp and serves as a welding surface 10. The area between the sleeves 26 is filled with an elastic, soft material 28. In the example of fig. 15, material 28 is injected over and under the connecting strips. This results in a flat resilient structure, i.e. the toothbrush has a flat front face 5 which deforms in use. In the example of fig. 16, the material 28 is only injected over the connecting strips. The shape of the surface 4 is influenced by the shape of the injection mould. In the case of fig. 16, the shape is chosen to produce a pillow that is as flexible as it is in use. Fig. 15d shows a view of the head part 1 with the inserted carrier element 2, wherein the connecting strips 27 of the connecting sleeve 26 and covered by the soft material 28 are only indicated for the sake of illustration.

Fig. 17a, b show longitudinal and transverse side views of another toothbrush, in which the carrier plate 2 is welded to the head part 1 only in 4 partial regions 10. The seat plate is particularly compliant by this 4-point suspension. For this purpose, the head part has lateral recesses 30, by means of which a cavity 32 below the carrier plate can be reached. The support plate is here clearly at a distance from the head part, i.e. more than 0.5 mm. Deposits between the brush head and the holder plate can be washed off well. The support plate is composed of a rubber-elastic material or a thin layer of a hard component, for example less than 1 mm, and can be flexibly offset relative to the welding surface 10. The support plate preferably has a lateral edge, not shown here, of 2 mm or more than 2 mm, so that the user cannot see the unattractive bristle melt.

All the above variants can also be realized as a replaceable head without the need for a permanent welding of the carrier element to the toothbrush handle. The flexible carrier plate can also assume a sensor function, for example for monitoring the contact pressure.

Claims (27)

1. A toothbrush, comprising:

a head portion (1) having a front face (5) and a rear face;

at least one carrier element (2) connected to the head part (1), wherein the at least one carrier element (2) is made of a hard plastic material and a soft plastic material and has a top side (4), a rear side (8) and a plurality of slots (6) extending between the top side (4) and the rear side (8) of the carrier element (2), wherein a welding edge (10, 10') made of a hard plastic material is provided at the rear side of the carrier element (2); and

a bristle bundle guided through the slit (6), wherein the bristles (3) have a rear end (3a) which is melted to form a coating (11), which coating (11) at least partially covers the rear face (8) of the at least one carrier element (2),

wherein the at least one carrier element (2) to which the bristle tufts are secured is connected to the head portion (1) such that a rear face (8) of the at least one carrier element (2) is spaced apart from a front face (5) of the head portion (1) so as to form a cavity (32) beneath the at least one carrier element (2); and

the at least one abutment element (2) is elastically deformable at least partially with respect to the head portion (1) such that the front face (5) exhibits a non-planar spatial conformation at least during use.

2. Toothbrush according to claim 1, characterized in that the carrier element (2) is flexible and the spatial structure of the front face (5) is configured such that the coating (11) formed by the melted rear ends (3a) of the bristles (3) at least partially covering the rear face (8) solidifies in a predetermined shape.

3. Toothbrush according to claim 1, characterized in that the carrier element (2) is flexible and the spatial shaping of the front face (5) is made such that the carrier element (2) with the bristles (3) is inserted under prestress into a recess (7) of the head part (1) in order to arch it.

4. Toothbrush according to claim 1, characterized in that the hard plastic material of the carrier element (2) has a predetermined thickness which allows deformation of the carrier element (2).

5. Toothbrush according to claim 4, characterised in that the hard plastic material of the carrier element (2) is polypropylene with a thickness of up to 3 mm.

6. Toothbrush according to claim 1, characterized in that the periphery of the carrier element (2) is at least partially made of a hard plastic material.

7. Toothbrush according to any one of claims 1 to 6, characterised in that the carrier element (2) has a plurality of sleeves (26) which are connected to one another by connecting strips (27) for receiving tufts of bristles, wherein the sleeves (26) and the connecting strips (27) are made of a hard plastic material and at least the space between the sleeves (26) and the connecting strips (27) is filled with a soft plastic material (28).

8. Toothbrush according to any one of claims 1 to 6, characterized in that there are at least two carrier elements (2) which are connected to the head part (1) at different positions such that the common front face (5) formed by the bristle-carrying top faces (4) of the carrier elements (2) has a non-planar shape.

9. Toothbrush according to claim 1, characterised in that the carrier element (2) and the head part (1) are weldable along said welding edge.

10. Toothbrush according to claim 9, characterised in that the welding edges (10, 10') lie in one plane.

11. Toothbrush according to claim 1, characterised in that the head part (1) is replaceable.

12. A toothbrush according to claim 1, characterised in that the at least one carrier element (2) comprises a flexible tooth cleaning element made of a soft plastic material.

13. The toothbrush according to claim 1, characterized in that the gap (6) is located partially in the soft plastic material of the at least one carrier element (2).

14. The toothbrush according to claim 1, characterized in that the gap (6) is located partially in the hard plastic material of the at least one carrier element (2).

15. The toothbrush according to claim 1, characterized in that the at least one carrier element (2) has a sleeve (26) made of a hard plastic material, the sleeve (26) comprising the slit (6) and the rear ends (3a) of the bristles (3) being melted into the sleeve (26).

16. The toothbrush according to claim 15, characterized in that the sleeve (26) is at least partially surrounded by a soft plastic material.

17. Toothbrush according to claim 1, characterised in that the at least one carrier element (2) is connected to the head part (1) only in a sub-region of its peripheral region.

18. The toothbrush according to claim 17, characterized in that the head part (1) has a lateral recess, by means of which access to the cavity (32) beneath the at least one carrier element (2) is possible.

19. The toothbrush according to claim 18, characterized in that the at least one carrier element (2) is spaced apart from the head part (1) by more than 0.5 mm.

20. A method of making a toothbrush according to any one of claims 1 to 19, the method comprising the steps of:

-making at least one seat element (2) from a hard plastic material and a soft plastic material;

-introducing bristles (3) through the slit (6) into said at least one seat element (2) and melting the rear ends (3a) of the bristles by means of a heating die (12) for connection with the seat element (2);

-connecting said at least one support element (2) to which the bristles are fixed to the head portion (1) of the toothbrush, so that said top surface (4) defining the front face (5) of said head portion (1) of the toothbrush can assume a non-planar spatial configuration at least when used as intended.

21. Method according to claim 20, characterized in that a flexible flat carrier element (2) is produced and the bristles are embedded, wherein the carrier element (2) is brought to assume a non-planar spatial shape by heating the die (12) during melting of the rear ends (3a) of the bristles.

22. A method according to claim 20, characterized in that a flexible flat carrier element (2) is prepared and provided with bristles, which carrier element is then inserted into a recess (7) in the head part (1) under prestress and connected to the head part (1) in such a way that the carrier element (2) is arched.

23. A method according to claim 20, characterized in that the carrier element (2) is manufactured in a two-component injection moulding from a hard plastic material and a soft plastic material, and is then fitted with bristles and connected to the head part (1).

24. A method according to claim 23, wherein said carrier element (2) with embedded bristles is connected to said head portion (1) by ultrasonic welding of a hard plastic material of said carrier element (2) to said head portion (1).

25. A method according to claim 23 or 24, characterized in that a number of sleeves (26) which are connected to one another by means of connecting strips (27) are injection-molded from a hard plastic material, and that during the injection-molding the gaps between the sleeves (26) and the connecting strips (27) are filled with a soft plastic material (28) and the bristle tufts are introduced into the sleeves (26).

26. A method according to claim 20, characterized in that at least one carrier element (2) with a non-planar top surface (4) is prepared and provided with bristles, and that the carrier element is then inserted into a recess (7) in the head part (1) matching the shape of the carrier element (2) in order to connect the carrier element (2) to the head part (1).

27. Method according to claim 20, wherein said at least one abutment element (2) is attached to said head portion (1) by ultrasonic welding.