WO2025061275A1

WO2025061275A1 - An applicator and method of forming an applicator

Info

Publication number: WO2025061275A1
Application number: PCT/EP2023/075884
Authority: WO
Inventors: Josef Moser; Jim GIGER
Original assignee: Medmix Switzerland AG
Current assignee: Medmix Switzerland AG
Priority date: 2023-09-20
Filing date: 2023-09-20
Publication date: 2025-03-27
Anticipated expiration: 2026-03-20

Abstract

The present application relates to an applicator, in particular a dental and/or medical applicator and to a method of forming such an applicator.

Description

An applicator and method of forming an applicator

The present invention relates to an applicator and to a method of forming an applicator such as a dental applicator and/or a medical applicator.

The present invention relates to an applicator, in particular to a dental applicator, the applicator comprising an applicator head with an applicator and an elongate body part, wherein the applicator is made from two parts of different material and comprises two kinks, with one of the two kinks being arranged at a part of the applicator where the two different parts at least partially overlap one another. The invention further relates to a method of forming an applicator.

Applicators are well known, particularly in the dental and medical field for treating e.g. a patient’s gums, his teeth, spaces between the teeth or the like. The applicators can be used to apply fluids, such as cremes, medicinal fluids, ointments and the like to parts of a patient’s mouth or body.

For carrying out the various tasks, the applicators generally have an application tip that is configured to carry out the precise application. For example, brushes are known for cleaning between a patient’s teeth, also foams are also known for applying a dental or medical fluid at an area of the mouth. Particularly with regard to hard to reach areas of the mouth it is desirable to provide an applicator that can be deformed for the specific application and that reliably maintains its shape after deformation.

Moreover, the application tips need to be secured to the handle of the applicator such that neither the application tip nor parts thereof fall off in use of the applicator. For this reason it is an object of the present invention to make available an applicator that is simple to use, that maintains its shape and form in use and that does not loose parts thereof in use and that is simple to manufacture.

This object is satisfied by the subject matter of the respective independent claim.

Such an applicator can be a dental applicator or a medical applicator, the applicator comprising an applicator head and an elongate body part, wherein the applicator head comprises material or is made from material that is different material from a material of the elongate body part, wherein the applicator head comprises bristles extending from and optionally overlapping a part of the elongate body part, with one or more holes extending through the application tip towards the elongate body part.

In this connection it should be noted that the dental and/or medical applicator can be used to introduce cleaning fluids, antiseptic fluids, adhesives, protective fluids or the like into a patients mouth and /or to apply these to a part of the patient’s skin.

The applicator may be a manual applicator.

The elongate body part may be formed as a handle for holding the applicator. Thereby the applicator is simple to use and manufacture

The applicator head may be formed as that part of the applicator comprising the part that is used to apply the fluid to a patient. Bristles may generally be elongate components that can be used to store liquid or fluid therebetween for application at a target site of a patient. The bristles may also be able to engage in gaps between a patients teeth.

The provision of holes increases the storage capacity for fluid at the applicator and aids in maintaining a shape and form of the applicator head in use.

Said one or more holes may have a size selected in the range of 0.2 to 0.9, especially of 3 to 0.8 mm. These sizes have been found to be beneficial to maintain the size and shape of the applicator.

The applicator head may comprise between one and 10000 holes, preferably between one and 200 holes, especially between one and 100 holes, further preferably between one and 50 holes. The provision of an applicator with e.g. between one and 50 holes ensures a stable applicator in use.

A front end of the applicator head may comprise a single central hole. Such a single hole can release surface tension in the applicator ensuring it maintains its shape and size in use.

The single central hole has a size selected in the range of 0.2 to 0.8 mm. Such sizes have been found beneficial to reducing the surface tension at the front end.

The applicator head may comprise two or more radial holes. Such radial holes can further decrease the surface tension in the applicator head

The two or more radial holes may have a size selected in the range of 0.2 to 0.9, especially of 3 to 0.8 mm. Such sizes of holes have been found beneficial. The applicator head may comprise an application tip comprising a base and the bristles may extend from the base, with the base having a thickness selected in the range of 0.1 to 0.8 mm. Such a base can be formed to ensure the applicator maintains it shape and form in use and also ensures that the bristles cannot tear off in use.

The part of the elongate body part which is covered by the application tip may be trapezoidal in shape and or cylindrical in shape. In this way the application tip can be formed in a simple and reliable manner at the elongate body part.

The application tip may overlaps a part of the elongate body part or extends through a part of the elongate body part, wherein the elongate body part may be made from one of PE, POM, ABS, PBT, PA, SB, PVC, PMMA, PS, PC, PPS, and metal and a material of the application tip may be selected from the group of members consisting of a thermoplastic elastomer, a thermoplastic polyurethane, a thermoplastic vulcanizate, a thermoplastic olefin elastomer, polyethylene, polypropylene, poly vinyl chloride, polyurethane, polystyrene, silicone and combinations of the foregoing.

Such materials of the application tip are flexible and soft in use for, e.g. dental applications and also permit the storage of fluid thereat. The use of harder materials for the elongate body part means this can be guided to the point of application more reliably than if a soft material is used and the material also provides an extra level of support for the desired application, e.g. the application of adhesive or a cleaning agent at the target site.

The application tip may be made from respectively may comprise silicone having a higher degree of cross-linking with oxygen, silicone made by addition curing (where polymer contains vinyl groups and crosslinking agent contains Si-H groups), a silicone having peroxide curing. A front end of the applicator may have a diameter selected in the range of 0.2 to 1 .2 mm. In this way an easy to use applicator can be provided that can access even remote and small spaces in a patient’s mouth.

The applicator may be made from two parts of different material, i.e. the elongate body part and the application tip, respectively the bristles. In the first case, the application tip may overlap the elongate body part and in the second case the bristles may extend from within the elongate body part.

The elongate body part may comprises a hollow front end as the first part with the application tip comprising bristles extending through holes in the hollow front end. Such a hollow front end enables a material of the applicator head to be injected through the hollow front end and be formed in a reliable manner at the elongate body part with the bristles e.g. being formed by pushing the molten melt through radial holes such that radial bristles are formed that are securely anchored to the elongate body part.

The elongate body part may comprises at least a first kink, optionally with a second kink being provided with the second kink then being arranged at a part of the applicator where the two different parts at least partially overlap one another.

The provision of one or two kinks enables the production of an applicator that can easily be deformed for the specific use of the applicator so as to reach hard to reach areas in the mouth of a patient.

By forming one of the one or two kinks in a region of the applicator where the two parts thereof overlap one another provides the applicator with an increased stability at this part of the applicator resulting in an applicator that can be deformed in a shape stable manner, with this change in shape also being maintained during the use of the applicator for improved application results.

A cross-section of the elongate body part along at least a majority of a length of the elongate body part may at least substantially be formed by one of a triangle and a Reuleaux triangle.

A second point of injection may be formed in a front hollow end of the elongate body part, with the front hollow end comprising holes.

For example, such an applicator, in particular a dental applicator, comprises an applicator head with an application tip and an elongate body part, wherein the applicator is made from two parts of different material and comprises two kinks, with one of the two kinks being arranged at a part of the applicator where the two different parts at least partially overlap one another.

By forming the applicator of two parts, in particular only two parts, avoids parts of the applicator from becoming detached during use so that an applicator is made available that does not lose any particles in use.

Moreover, by forming the applicator of two parts of different material, each part can be tailored to its specific use.

For example, the provision of an elongate body part as a handle enables a good tactile control of the application tip during the use of the applicator specifically if this is made of a harder, less flexible material and hence a more robust material than the applicator head.

Moreover, the provision of an applicator head with an application tip that is e.g. integrally formed in one piece with the application tip reduces the number of differ- ent components of an applicator and hence reduces the risk of losing parts of the applicator on use thereof.

Such an applicator head formed of a second material can for example be formed of a material that is softer and/or more flexible than a material of the elongate body part and hence be used more effectively for the specific application.

The provision of two kinks enables the production of an applicator that can easily be deformed for the specific use of the applicator so as to reach hard to reach areas in the mouth of a patient.

By forming one of the two kinks in a region of the applicator where the two parts thereof overlap one another provides the applicator with an increased stability at this part of the applicator resulting in an applicator that can be deformed in a shape stable manner, with this change in shape also being maintained during the use of the applicator for improved application results.

One of the two parts made from a different material may be the elongate body part and the other of the two parts made from a different material may be the applicator head, preferably with the applicator head comprising the application tip that is integrally formed thereat. An applicator having such a design is more stable in use and avoids the problems of the prior art associated with losing parts thereof.

Some of the applicator head may overlap some of the elongate body part. In this way an applicator can be formed, e.g. in an injection molding process or an additive manufacturing process with the two parts being non-releasably attached to one another during normal use of the applicator.

A cross-section of the elongate body part along at least a majority of a length of the elongate body part is formed at least substantially by one of a triangle and a Reuleaux triangle or is formed by one of a triangle and a Reuleaux triangle. Form- ing the applicator in this way ensures that this does not role on a surface on which it is placed causing the application tip from being contaminated in use necessitating the use of a further applicator increasing the time and cost of a treatment.

In this connection a majority means more than half of a length of the elongate body part, specifically more than 70% and preferably more than 85% of a length of the elongate body part.

The application tip may comprise one of a brush with bristles and a foam. Such application tips can be reliably used for different medical and dental applications.

The application tip may be configured to store a liquid thereat. In this way a dental fluid can be introduced into the mouth of a patient for treatment of a target site, or unwanted fluid can be removed from a patient following a successful treatment of the patient. By way of example the application tip can be configured to store between 6 and 15 mg of dental fluid, preferably between 8 and 12 mg of dental fluid.

One of the two kinks may be arranged directly adjacent to that part of the elongate body part that is formed at least substantially by the Reuleaux triangle or the triangle. In this way one of the kinks can be formed at a part made of material that is stable in shape and form even after it has been deformed.

The application tip may be a brush with bristles, with the brush and bristles being formed by at least one of a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU), a thermoplastic vulcanizate (TPV), and a thermoplastic olefin elastomer (TPO). In this way a simple to use applicator can be made available.

By way of example such materials can be Santoprene 8281 , further examples of TPE materials that come from block copolymers group are amongst others CA- WITON, THERMOLAST K, THERMOLAST M, Arnitel, Hytrel, Dryflex, Mediprene, Kraton, Pibiflex, Sofprene, and Laprene. Out of these styrenic block copolymers (TPE-s) are CAWITON, THERMOLAST K, THERMOLAST M, Sofprene, Dryflex and Laprene. Laripur, Desmopan or Elastollan are examples of thermoplastic polyurethanes (TPU). Sariink, Santoprene, Termoton, Solprene, THERMOLAST V, Vegaprene or Forprene are examples of TPV materials. Examples of thermoplastic olefin elastomers (TPO) compound are For-Tec E, Engage and Ninjaflex.

The two kinks may be configured to be bent in one direction, in particular in only direction, especially such that the application tip may face upwardly relative to the elongate body part. This means that the applicator may be bent in one direction at each kink so that a hook shaped applicator or the like is formed in use providing sufficient degrees of freedom of use of the applicator.

At least one of the two kinks may be configured as a peripherally extending groove, for example, the groove has a round, circular, oval, triangular crosssection transverse to a longitudinal axis of the applicator. The provision of an applicator with such grooves enables the applicator to be bent by 360° relative to the longitudinal axis so that the user thereof can manipulate the position of the application tip for his specific desired use.

The applicator head may be made from a material different from the elongate body part. For example, the applicator head may be made from a material that is softer and/or more flexible than a material of the elongate body part. This means that the applicator head can be tailored to the specific use of the applicator.

The elongate body part may be made from one of polypropylene and polylactide. Such plastics are stable in shape and size also after they have experienced a certain deformation.

The applicator head may comprise a material selected from the group of members consisting of a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU), a thermoplastic vulcanizate (TPV), a thermoplastic olefin elastomer (TPO), polyethylene (PE), polypropylene (PP), poly vinyl chloride (PVC), polyurethane (PU), polystyrene (PS) and combinations of the foregoing. Such thermoplastic elastomers are flexible and soft in use for, e.g. dental applications and also permit the storage of fluid thereat.

The applicator head may be configured to receive a part of the elongate body part. This means that parts of the elongate body part may extend into and possibly through some of the applicator head for improved attachment of the applicator head at the elongate body part.

The part of the elongate body part received within the applicator head may comprise one or more centering elements, for example, two groups of centering elements are provided that are axially spaced apart from one another. The centering elements enable the precise positioning of the applicator head at the elongate body part and may also provide a security against rotation in order to prevent a rotation of the applicator head relative to the elongate body part.

One of the kinks may be arranged at that part of the applicator head and that part of the elongate body part that is received within the applicator head. In this way the second kink is also provided in that part of the applicator that has the harder and more rigid material properties than the applicator head.

The application tip may be a foam application tip made from an open cell foam having pores. Such an application tip can be used to distribute dental or medical fluids in an expedient manner.

The applicator may further comprise an undulating surface or the like. Such an undulating surface may act as a grip for holding the applicator. In this connection it should be noted that other forms of grip may likewise be provided that have enable an improved gripping of the applicator in use. The undulating surface may be provided to cover between 5 and 30 %, preferably between 10 and 25% of the outer surface of the elongate body part. In this way a length of the grip can be selected such that it approximately amounts to a length corresponding to between 1 to 3 widths of fingers of a user of the applicator.

The undulating surface may comprise a plurality of peaks and valleys. Such undulating surfaces are simple to manufacture e.g. in an injection molding process.

The applicator may comprise one or more first points of injection. These can beneficially be formed at that part of a mold used to form the elongate body part.

The one or more first points of injection may be provided at the elongate body part. In this way a material of the elongate body part can be injected into a corresponding mold at that part of the mold designed for the elongate body part in such a way that a material of the elongate body part does not have to flow through nondesirable regions of the mold.

One of the one or more first points of injection may be provided at the undulating surface. Since the structure of such an undulating surface may be more filigree than that of the elongate body part it may be necessary to provide a point of injection at a position that corresponds to that part of the mold where the undulating surface is formed, such that the material can flow more easily into the part of the mold shaped for molding the undulating surface, i.e. the grip.

One or more second points of injection may be provided. These can preferably be designed for injecting a second kind of material into the mold of the applicator.

By way of example, the one or more second points of injection may be provided at the applicator head. In this way the second points of injection can beneficially be arranged at a position where the injection mold injects the material for the applicator head.

Beneficially the one or more second points of injection may be provided at the kink arranged at the applicator head. In this way the material of the applicator head can flow more easily around the kink and possibly also in the region of at least one of the first and second types of centering element.

According to a further aspect the present invention relates to a method of forming an applicator, in particular a dental applicator, the applicator comprising an applicator head with an application tip and an elongate body part, wherein the applicator is made from two parts of different material and comprises two kinks, with one of the two kinks being arranged at a part of the applicator where the two different parts at least partially overlap one another, the method comprising the steps of injection molding the elongate body part and then injection molding the applicator head with parts of the applicator head being overmolded onto parts of the elongate body part.

In this way the applicator can be manufactured in a fast, facile and cost effective manner.

An applicator as described in the foregoing can be formed using a method of forming the applicator, the method comprising the steps of providing the elongate body part having the channels and introducing a melt of material of the bristles with a sufficiently high mold pressure as to shoot-through the elongate body part in a vicinity of the free cross-section of the channels thereby displacing carrier material, with the melt subsequently filling the channels, wherein the carrier body acts as a pressure holding barrier during injection molding of the melt up to a point in time at which penetration of the melt through the carrier body begins with the melt subsequently penetrating explosively into the channels to form the monofilament bristles and evenly displace carrier material around a foot of the bristles to fix the carrier body to the monofilaments.

The step of providing the bristles at the elongate body part may comprise forming the applicator head at the elongate body part.

The method may further comprise the step of injecting a material of the application tip through the elongate body part.

The application tip may be formed by from plastic melt by injection molding in bristle forming channels.

Further embodiments of the invention are described in the following description of the figures and/or the dependent claims attached to this specification. The invention will be explained in the following in detail by means of embodiments and with reference to the drawing in which is shown:

Figs. 1 a & b side views of an applicator and an elongate body part thereof;

Fig. 2 view of an applicator head of the applicator of Fig. 1 a;

Figs. 3a & b a side view and a perspective view of a connecting portion of the elongate body part of Fig. 1 b;

Figs. 4a &B a front view of the applicator of Fig. 1 a and a view of the circumference of the elongate body part of Fig. 1 b;

Fig. 5 a view of a further applicator head;

Fig. 6 a view of a further applicator head;

Fig. 7 a view of a further applicator head; and

Figs. 8a to 8c a further type of applicator.FIG. 9 shows a schematic representation of a molding tool in a first method step;

FIG. 10 the molding tool of Fig. 9 in a second method step;

FIG. 1 1 a detailed view of FIG. 9; FIG. 12 a detailed view of FIG. 10;

FIG. 13 a first highly enlarged cut in the vicinity of the free opening cross-sections of the molding channel;

FIG. 14 a second highly enlarged cut in the vicinity of the free opening crosssections of the molding channel;

FIG. 15 a third highly enlarged cut in the vicinity of the free opening cross-sections of the molding channel;

FIG. 16 a plan view onto the free cross-section of another embodiment of the molding channel;

FIG. 17 a cut through a molding tool for processing a carrier having a plurality of layers;

FIG. 18 is a schematic side view of a carrier for the head of a toothbrush;

FIG. 19 is a view onto the bristles field of the head of a toothbrush;

FIG. 20 is a view of another embodiment corresponding to FIG. 19;

FIG. 21 is a partial cut through the head of a toothbrush in an additional embodiment;

FIG. 22 a first embodiment of the configuration of intended breaking locations on the carrier, in plan view;

FIG. 23 a second embodiment of the configuration of intended breaking locations on the carrier, in plan view;

FIG. 24 a third embodiment of the configuration of intended breaking locations on the carrier, in plan view;

FIG. 25 a fourth embodiment of the configuration of intended breaking locations on the carrier, in plan view;

FIG. 26 is a plan view onto an embodiment having weakened locations in a foil of a carrier constituting a kind of stretching foil;

FIG. 27 is the embodiment of FIG. 26 after the effect of the molding pressure, in cross-section;

FIG. 28 a plan view onto a first embodiment of a carrier having a grid-like configuration of intended breaking locations; FIG. 29 a plan view onto a second embodiment of a carrier having a grid-like configuration of intended breaking locations;

FIG. 30 a plan view onto a third embodiment of a carrier having a grid-like configuration of intended breaking locations;

FIG. 31 a first embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 32 a second embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 33 a third embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 34 a fourth embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 35 a fifth embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 36 a sixth embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 37 a seventh embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 38 an eigth embodiment of intended breaking locations on thick carriers, in cross-section;

FIG. 39 schematically a section of a carrier having different intended breaking locations and differing mold masses;

FIG. 40 a detailed cut of a carrier having a shaping shoulder;

FIG. 41 is the carrier in accordance with FIG. 40 subsequent to introduction of the molding mass;

FIG. 42 is a detail of an embodiment, which is changed with respect to FIG. 40;

FIG. 43 is the embodiment of FIG. 42 following introduction of the mold mass;

FIG. 44 is a schematic representation of the sandwich molding procedure using the mono method;

FIG. 45 the article produced using the method in accordance with FIG. 44; FIG. 46 is a schematic representation of a cut through an injection molding apparatus for use in the twin-shot procedure;

FIG. 47 the head of a toothbrush in longitudinal section;

FIG. 48 the head of a toothbrush in transverse section;

FIG. 49 a star-shaped blank made from strip-shaped bristles elements, in plan view;

FIG. 50 a side view of a portion of the blank in accordance with FIG. 49;

FIG. 51 a cut through the strip-shaped blank;

Fig. 52. a part sectional view of a further applicator;

Fig. 53 a schematic view of a further applicator;

Fig. 54 a schematic view of a further applicator; and

Fig. 55 a part schematic view of a further applicator.

In the following the same reference numerals will be used for parts having the same or equivalent function. Any statements made having regard to the direction of a component are made relative to the position shown in the drawing and can naturally vary in the actual position of application.

Fig. 1 a shows an applicator 10. The applicator 10 comprises an applicator head 12 with an application tip 14 and an elongate body part 16. The applicator 10 is made from two parts 16, 12 of different material. One of the two parts made from a different material is the elongate body part 16 and the other of the two parts 16, 12 made from a different material is the applicator head 12.

The applicator further comprises first and second kinks 18, 20, with one of the two kinks 18 being arranged at a part of the applicator 10 where the two different parts 12, 16 at least partially overlap one another.

The application tip 14 comprises a brush 24 with a plurality of bristles 26. The bristles 26 are dimensioned for the specific application. The brush 24 and the bristles 26 are formed by a thermoplastic elastomer (TPE). The application tip 14 is configured to store between 5 and 15 mg of a liquid (not shown) thereat.

In this connection it should be noted that a hardness of the application head 12 and of the application tip 14 may be selected in the hardness range 20 Shore 00 up to 90 Shore A.

The bristles 26 may have a diameter selected in the range of 0.1 to 1 mm and/or a length selected in the range of 0.2 to 4 mm.

The bristles 26 may be of cylindrical shape or have the shape of a truncated cone, with the diameter then being the diameter at half of the length of the bristle 26.

The number of bristles may be selected in the range of 20 to 100, preferably in the range of 30 to 50.

Fig. 1 b shows a side view of the elongate body part 16. A cross-section of the elongate body part 16 is formed by a Reuleaux triangle between the second kink 20 and a rear end 38. The elongate body part 16 may have this shape over 60 to 85% of a length L thereof, preferably over 75 to 80 % of its length.

The applicator head 12 is made from a material different from the elongate body part 16. The elongate body part 16 may be made from one of polypropylene PP and polylactide PLA.

In this connection it should be noted that a hardness of the elongate body part 16 may be selected in the hardness range Shore D hardness between 45 and 96, preferably between 70 and 90 shore D hardness.

A front end 40 of the elongate body part 16 comprises first and second types of centering elements 30, 32 that are used on molding the applicator head 12 over and onto some of the elongate body part 16 to center the applicator head 12 at the elongate body part 16 and to provide a security against rotation at the elongate body part 16 in order to prevent a rotation of the applicator head 12 relative to the elongate body part 16 in use thereof.

The applicator head is molded over some of the elongate body part 16 with a layer thickness selected in the range of 0.05 to 3 mm, preferably within the range of 0.1 to 2 mm.

Fig. 2 shows an enlarged view of the brush 24 of the applicator 10 of Fig. 1 . The second type of centering elements 32 are visible as these not only extend into the applicator head 12, but also through the applicator head 12.

In contrast to this the first type of centering elements 30 only extend into the applicator head 12 but not through the applicator head 12.

A height of the first and second types of centering elements 30, 32 in a direction transverse to the longitudinal axis A, may be selected in the range of 0.05 to 3 mm, preferably in the range of 0.1 to 2 mm.

In this connection it should be noted that a length of the first type of centering elements 30 transverse to the longitudinal axis A may be selected in the range of 0.1 to 10 mm, preferably in the range of 0.3 to 5 mm.

In this connection it should be noted that a width of the first type of centering elements 30 in parallel to the longitudinal axis A may be selected in the range of 0.01 to 5 mm, preferably in the range of 0.05 to 1 mm. In this connection it should be noted that a length of the second type of centering elements 32 along the longitudinal axis A may be selected in the range of 0.1 to 5 cm, preferably in the range of 0.3 to 2 cm.

In this connection it should be noted that a width of the second type of centering elements 32 along the longitudinal axis A may be selected in the range of 0.1 to 10 mm, preferably in the range of 0.5 to 5 mm.

The second type of centering elements 32 are arranged between the application tip 14 and the first kink 18.

Both the first and second types of centering elements 30, 32 are formed as rectangular structures that engage the applicator head and prevent a movement thereof relative to the elongate body part 16.

On forming the applicator head 12 over the elongate body part 16 one forms a continuous outer surface 44 of the applicator 10, with an outer part of the second type of centering elements 32 forming a part of the continuous outer surface 44.

The applicator head 12 tapers in diameter between the second kink 20 and the application tip 14.

Fig. 3a shows a side view of the elongate body part 16 and Fig. 3b shows a perspective view of a connecting portion 36 of the elongate body part 16. The applicator head 12 is injection molded over the elongate body part 16 over the length of the connecting portion. A length of the connecting portion 36 is selected as 10 to 30 % of a length L of the elongate body part 16 between the front end 40 and the rear end 38. Figs. 4a and 4b show enlarged views of the triangular shape of the applicator 10, with Fig. 4a showing the application tip 14 attached and Fig. 4b showing the application tip 14 removed from the elongate body part 16.

The first kink 18 is arranged at the connecting portion 36, i.e. at that part of the applicator 10 where the applicator head 12 is overmolded onto the elongate body part 16, whereas the second kink 20 is arranged only at the elongate body part 16.

Both the first and second types of centering elements 30, 32 project from an outer surface 42 of the connecting portion 36.

The first type of centering elements 30 are arranged transverse to the second type of centering elements 32 and also transverse to a longitudinal axis A of the applicator 10 that extends in parallel to the main direction of extent of the applicator 10. By arranging the first and second types of centering elements 30, 32 transverse to one another a security against rotation can be improved.

The second type of centering elements 32 are arranged in parallel with the longitudinal axis A of the applicator 10.

The two types of centering elements 30, 32 are arranged axially spaced apart from one another, with the second type of centering elements 32 being arranged between the first type of centering elements 30 and the second kink 22.

In this connection it should be noted that a spacing between the first and second types of centering elements 30, 32 along the longitudinal axis A may be selected in the range of 0.1 to 5 cm, preferably in the range of 0.5 to 3 cm.

In the shown examples two first types of centering elements 30 and two second types of centering elements 32 are provided in respective groups, with each cen- tering element 30, 32 of a respective group being arranged at opposite sides of the elongate body part 16.

In this connection it should be noted that between 1 and 4 of such first and second types of centering elements 30, 32 can respectively be provided, i.e. one of each our of each or one first and four second types of centering elements 30, 32.

The second kink 20 is arranged directly adjacent to that part of the elongate body part 16 that is formed at least substantially by the Reuleaux triangle.

The two kinks 18, 20 are configured to be bent in one direction while being able to be bent at any angle in the radial direction by 360° relative to the longitudinal axis. The triangular shaped body permits the applicator 10 to lie on a flat surface without rolling off and the applicator 10 can be placed onto the flat surface with the application tip 14 facing away from the flat surface, i.e. relative to the elongate body part 16.

The first and second kinks 18, 20 are each configured as a peripherally extending groove 22. The groove 22 can have one of a round, circular, oval, and triangular cross-section transverse to a longitudinal axis A of the applicator 10.

A width of the groove 22 of second kink 20 is larger than a width of the groove 22 of the first kink 20 in a direction transverse to the longitudinal axis A.

In this connection it should be noted that a width of the groove 22 of the second kink 20 can be selected in the range of 1 % to 5 % of a length L of the applicator 10.

In this connection it should further be noted that the second kink 20 is arranged at a length corresponding to 10 to 30 % of a length L of the applicator 10. In this connection it should be further noted that a width of the groove 22 of the first kink 18 is selected in the range of 0.2 to 1 % of a length of the applicator 10.

In this connection it should further be noted that the first kink 18 is arranged at a length corresponding to 2 to 10 % of a length L of the applicator 10.

Fig. 5 shows a view of a further applicator 10, with a foam application tip 14 made from an open cell foam having pores 34. The material of the application tip 14 made of foam may be one of polyethylene (PE), polypropylene (PP), poly vinyl chloride (PVC), polyurethane (PU), polystyrene (PS) and combinations of the foregoing.

Fig. 6 shows a view of yet a further applicator head 12. The application tip 14 has four claws 44 that form a cage 46 in which a fluid may be collected on use of the applicator 10 of Fig. 6.

The claws 44 are connected at each end to one another and are curved in shape and merge into a tip 48 at a most distal point of the applicator 10.

Fig. 7 shows a view of yet a further applicator head 12. The application tip 14 is a brush 24 with bristles 26. In contrast to the brush 24 with bristles 26 shown in connection with Figs. 1 to 4, the bristles 26 extend in parallel to one another and only in two directions that are oppositely disposed with respect to the longitudinal axis A rather than radially with respect to the longitudinal axis A.

A method of forming the applicator 10 may comprise the steps of injection molding the elongate body part 16 and then injection molding the applicator head 12 over and onto parts of the elongate body part 16. On using the applicator 10 a user can decide where the applicator 10 is intended to be used and then bend the application tip 14 relative to the elongate body part 16 at least once at one of the first and second kinks 18, 20 prior to using the application tip 14 even at hard to reach target cites.

Figs. 8a to 8c show a further type of the applicator 10. This applicator 10 comprises an undulating surface 46. Such an undulating surface 46 can be beneficially used by a user of the applicator 10 to grip the applicator 10 in an improved manner.

The undulating surface 46 is provided to cover approximately 20% of the outer surface of the elongate body part 16. In this connection it should be noted that it could be arranged to cover between 5 and 30 %, preferably between 10 and 25%, of the outer surface of the elongate body part 16.

The undulating surface 46 comprises a plurality of peaks 52 and valleys 54. In the example shown 13 peaks 52 and 12 valleys are provided. In this connection it should be noted that a respective number of peaks 52 and valleys 54 selected in the range of 5 to 40 can be provided. It is generally desirable if the number of peaks 52 provided is one more than the number of valley 54, i.e. if six peaks are provided then 5 valleys 54 may be provided and if 40 peaks 52 are provided then 39 valleys 54 may be provided.

As can also be seen from Fig. 8a two first points of injection 48 and one second point of injection 50 are provided. The first points of injection 48 are provided at the elongate body part 16 and the second point of injection 50 are provided at the applicator head 12.

As can be seen from the enlarged view of Fig. 8b one of the first points of injection 48 is provided at the undulating surface 46 and the second point of injection 50 is provided at the kink 18 arranged at the applicator head 12. In this connection it should be noted that the term point of injection refers to a formation at which the material of the respective component is injected into a mold for forming the applicator 10, with the formation remaining visible at the outer surface of the applicator 10 in the region of where the respective material was injected into the mold for the formation of the corresponding part of the applicator 10.

Fig. 8c shows a side view of the applicator of Fig. 8b indicating the position of the formations remaining after formation of the respective part, i.e. their points of injection 48, 50.

The respective point of injection 48, 50 is provided in the vicinity of a filigree component to be formed as the material will flow best out of an injection nozzle (not shown) at this point as it has the highest temperature and pressure at the injection nozzle meaning that it will flow best into these filigree components from the injection nozzle.

It should also be noted that the grip shown in the manner of an undulating surface 46 in Figs. 8a to 8c can also be formed at the other kinds of applicators 10 shown in the foregoing. Similarly the other kinds of applicators may also have the first and second points of injection that are respectively present at regions of the applicator 10 where the material can be beneficially injectied into a mold for forming the respective part at increased efficiency and with improved results.

FIG. 9 schematically shows a molding tool 101 , or a portion thereof, which is preferentially not of solid construction, rather is built up from parallel layered plates 102 whose purpose and action are described more closely in WO 02/03831 (DE 10033256 and DE 10130863) and in the unpublished patent applications DE 10301635.6 and DE 10212781 .8, both due to the assignee of the instant application. The mold tool has a tool portion 101 having a plurality of preferentially parallel channels 103 in which the bristles are molded. The channels 103 extend from mold walls 104 and preferentially travel in a slightly conical fashion towards their closed ends. A carrier 107 is inserted into the mold cavity 105 onto the molding walls 104 and covers the free cross-section 6 of the molding channels 103.

The mold tool can be an injection molding, a pressure molding or a press-molding tool. The mold mass for the bristles is introduced into the mold cavity 105 with a sufficient amount of pressure to penetrate or shoot through the carrier 107 in the vicinity of the free cross-section 106 of the mold channel 103 (see FIG. 10). After penetration or shooting-through of the carrier 107 the mold mass forming the bristle 106 in the channels 103 can simultaneously serve to form the back of the carrier 107 (reference symbol 108) to cover same and thereby form a complete carrier of a bristle element.

FIGS. 11 and 12 show a detailed variation with reference to a single mold channel 103. In this case, the mold channel 103 has an enlargement 109 disposed at the introductory side thereof into which the carrier material which is displaced when the carrier 107 is penetrated or shot through, flows, (FIG. 12). In this fashion, a collar 110 is formed within the enlargement 9 that supports the foot region of the bristles 106. For removal from the mold, the plates are displaced either individually or in groups such that the bristles 106 can be easily removed even in the event of substantial lengths.

FIGS. 13 through 15 show the introductory region of the channels 103 forming the bristles in enlarged, detailed view and illustrate its influence on the collar and the displacement of the carrier material during penetration of the mold mass. An entrance region having sharp edges (see FIG. 13) supports the breaking-through of the carrier material in the vicinity of the free cross-section 6 of the mold channel but also disadvantageously increases the probability that the carrier material is dragged along into the mold channel 103. In the event that the mold channel 103 has a more or less funnel shaped entrance in the vicinity of its free cross-section 106, the carrier material which is displaced by the mold mass under the influence of the mold pressure is evenly forced into the mold channel to form a proper collar. This improves the statics of the bristle produced thereby.

The embodiment in accordance with FIG. 16 shows a plan view onto the entrance region of the mold channel 103 which, at least in the vicinity of its free crosssection 106, has a corrugated shape as indicated by reference symbol 11 1. This shape supports penetration of the mold mass through the support 107. The structuring can extend along the entire length of the molding channel or can slowly map into a smooth-walled mold channel.

In accordance with FIG. 17, an additional carrier 1 12 having through holes 1 13 is initially disposed on the mold walls 104 from the which the mold channels 103 extend, with the actual carrier 107, which covers the molding channels 103 and the holes 1 13 being disposed thereon. The through holes 1 13 can have a somewhat larger diameter. In response to the mold pressure, the mold mass penetrates through the carrier 107 in the vicinity of the through holes 1 13 which then accept the displaced carrier material. The carriers 107 and 1 12 can preferentially be made from differing materials. For example, the carrier 1 12 can be made from a relatively soft elastomer and the carrier 107 from a harder material. Alternatively, the carrier 107 can also be directly disposed onto the mold walls 104 and a carrier similar to the carrier 1 12 can be disposed thereon. In this latter case as well, a hard/soft combination of material is conceivable.

FIG. 18 shows a carrier 107 which e.g. can be used for the production of the head region of a toothbrush. This carrier has a thickness which decreases along its length in order e.g. to provide progressive flexibility. However, in order to have uniform conditions when the mold mass is injected, the support 107 is provided with bottom holes 1 14 having a depth which is such that the wall thickness 15 through which the mold mass must penetrate or shoot always remains the same. The bottom holes 114 or the cross-section 14 which is to be penetrated can optionally be respectively associated with a plurality of mold channels such that, as shown in FIGS. 119 and 120, a bristle stock having differently configured bristles fields 116, 117, 118, and 119 or longitudinally extending bristles fields 120, 121 (FIG. 19) can be obtained. As is shown in FIG. 21 , the molding mass for the bristles filling the bottom holes 114 can also fill a continuous recess 122 formed on the back of the support 107, as is shown in FIG. 21 .

FIG. 22 through 25 show various embodiments for weakening the carrier 107 in the region of the free cross-section of the bristle forming channels. Each of such weakenings preferentially comprises radially symmetric intended breaking location 123 of differing configuration, wherein the central portion can optionally exhibit a particularly thin intended breaking location 124 (FIG. 25).

In the event of a thin carrier, in particularly stretching foils, a radially symmetric configuration of weakening lines 125 can be used to assure that the foil does not tear when the molding mass penetrates, rather stretches in a funnel-shaped fashion as is shown in FIGS. 26 and 26, so that a proper collar 126 is obtained. In the event of liquid melt mold masses e.g. in pressure molding or injection molding, both the breaking-open of the thinned locations as well as the stretching (see FIGS. 26 and 27) are supported by the temperature of the melt and the pressure wave which precedes the melt and which forces air out of the molding cavity. If, for example, the carrier is made from polypropylene having a melting temperature of 160 degrees and the bristle from polyamide 6.6 having a melting temperature of 260 degrees, it is clear that the temperature has a substantial influence on the breaking-through and displacement of the carrier material. Conversely, by proper matching of the two materials such that they both have nearly the same melting temperature, a melting and welding together of the carrier and bristle material can be effected. Particularly in the event of a very dense pack of bristles, the carrier 107 can be configured with grid-like, point shaped intended breaking locations 127 (FIG. 28) or with intended breaking locations forming gridlines 128 (see FIGS. 29 and 30). FIGS. 31 to 38 show differing embodiments of intended breaking locations, in particular for thicker carriers. FIG. 31 shows a funnel shaped intended breaking locations 124 each of which is associated with a bristle shaping channel. FIG. 32 shows a trough-shaped intended breaking location 130 and FIG. 33 shows a funnel shaped intended breaking location 131 with a protrusion 132 on the opposite side. Such shaping supports proper collar formation. These intended breaking locations can be disposed on that side of the support 107 which faces the molding pressure or alternatively, as shown in FIG. 34, on the side facing away from the molding pressure. Dome-shaped intended breaking locations 132 are shown.

In FIG. 35, the support 107 is given a funnel-shaped intended breaking location 133 at the side facing away from the mold pressure which extends, on the side facing the mold pressure, into a cone-shaped or pyramid-shape tip 134. In response to the molding pressure, the tip folds over in the direction towards the bristle shaping channel, as is indicated with the dashed lines. FIG. 36 shows a bowlshaped intended breaking location 135.

The intended breaking location 136 in accordance with FIG. 37 deviates from that shown in FIG. 32 in that the carrier material is additionally bulged in the direction towards the bristle shaping channels. FIG. 38 illustrates the material-weakening of the carrier 107 from both sides, each due to a respective hollow 137 and 138.

FIG. 39 shows a carrier 107 having intended breaking locations leading to differing weakenings thereof. The dome-shaped recess 139 leaves a material bridge 140 of less thickness than the dome-shaped recess 141 so that a greater wall thickness 142 remains. In response to injection of a first mold mass 143 with a particular mold pressure, those locations having the lowest residual wall thickness 140 break. In response to subsequent injection of an additional mold mass 144 at a higher mold pressure, the intended breaking locations having greater residual wall thicknesses 142 also break. In this fashion, it is possible to produce bristles 145, 146 from differing plastic on one single carrier 107, wherein the last mold mass injected can simultaneously constitute the back of the carrier 147. The bristles 145, 146 can also have differing shapes and cross-sections and could even be used to generate panel-shaped cleaning elements.

The carrier 107 can have shoulders 148 disposed on its side facing the bristle shaping channel which can partially dip into the bristle shaping channel and which can have intended breaking location 149 on their ends so that the mold mass 149 introduced at the mold pressure initially fills the channel 150 in the shoulder 148 before it breaks through the intended breaking location 149 and penetrates into the mold channel to form the bristle 151 . The bristle 151 is thereby wrapped within the shoulder 148 along an extensive length (FIG. 41 ).

The carrier in accordance with FIG. 42 also has a shoulder 152 with a bottom hole 153 whose floor has a plurality of thin locations (not visible). After the mold mass 54 is introduced, the bottom of the shoulder 152 tears at the thin locations to form short needle-shaped bristles 154 on a pin-shaped support.

FIG. 44 shows a schematic partial section of a two part molding tool 101 for use in the sandwich injection molding procedure. In this case, a mold mass 156 is initially introduced into the molding cavity 155 at a relatively low pressure such that the molding cavity 155 is not completely filled with the mold mass 156 seating on the mold walls. Due to the low mold pressure, the mold mass 156 is not able to overcome the flow resistance presented by the free cross-section of the bristle forming channels and therefore only penetrates into the region proximate the openings. This mold mass solidifies quickly at the cool mold walls and the second mold mass 157 can be subsequently injected. This second mass penetrates through the “plugs” formed by the first mold mass 156 in the vicinity of the opening crosssection and the “plugs” are thereby transformed into collars, as is shown in the shoulder region of the bristle 58 in FIG. 45.

The sandwich injection molding procedure can be effected by means of one single injection screw or in accordance with the so-called twin-shot method using two concentric injection screws. This procedure is schematically shown in FIG. 46. One portion of the two-sided mold tool 101 having the mold cavity 159, e.g. for production of a complete brush body has the channels 60 for shaping the bristles. The injection molding device consists essentially of an inner injection screw 161 which is disposed within an external injection screw 162 and which penetrates through the injection channel of that outer screw 162. The mold mass 163 is introduced via the outer injection screw 162 and only partially fills the mold cavity 159. This is effected with relatively high screw injection pressure. However, in response to that injection, only a portion of the mold is filled up and the pressure in the mold cavity thereby drops to several tens of bars (0.01 x 105 kPa) so that the mold mass 163 does not penetrate into the mold channel 60. In a subsequent step, the mold mass 164 is introduced in a second shot at a higher injection pressure. It is thereby injected in a mold-filling fashion and therefore has sufficiently high pressure within the mold cavity 159 to fill-up the mold channels 160.

The carrier can be injected using the GIT method (gas injection technology) or using the WIT procedure (water injection technology) that initially lead to a hollow mold body as a support from which the auxiliary fluid is subsequently removed. The resulting cavity can then be filled with a second mold mass, which simultaneously fills the channels forming the bristles. In this manner, brush bodies can be made using materials, which are tailored to their respective application.

An example is schematically shown in FIGS. 47 and 48 for the case of a toothbrush head 165, with FIG. 47 showing a longitudinal cut and FIG. 48 a transverse cut. The head consists essentially of a core 166 made from a relatively hard material, which is surrounded by a soft mucous membrane protection 167 which, for its part, is integral with blade-shaped cleaning and massaging elements 168 which are disposed on the side surface of the bristle stock having bristles 169. At the bristle back, the core 166 is filled up with the mold mass 170 forming the bristles 169. In this case, the mold mass for the bristle 169 is shot through the core 169 and the mucous membrane protection 167.

Single or multi-layered carriers of sufficient flexibility can be wrapped about rigid support structures in order to create round bristle elements. They can also be bent into structured objects, e.g. into U-shaped structures. They can also be shaped and bent into seals, in dependence on the application. These examples are only a few of all conceivable ones.

An example is shown in FIGS. 49 through 51. A star-shaped blank 171 made from a flexible carrier 172 (FIG. 51 ) is penetrated through by a mold mass for the bristles, in accordance with the invention. The mold mass can simultaneously form an additional layer 174. Holding elements 175 are formed on the ends of the stripshaped carrier 172 and can be fixed to a handle or the like or joined together after the strip-shaped carrier is bent into a three-dimensional object, e.g. a spherical or pear shaped object. The three-dimensional active regions can thereby be expanded through arrangement of a plurality of such star-shaped objects offset at angles with respect to each other, as indicated by the reference number 176, and connected to each other in a central region.

Fig. 52 shows a part sectional view of a further applicator 10. The bristles 26, 106 extend from a base 56 of the application tip 14. The base 56 is formed by the same material as that of the bristles 26, 106. The base 56 envelopes, i.e. overlaps, the elongate body part 16. A plurality of holes d2 extends through the base 56 of the application tip 14 towards the elongate body part 12 in a radial direction with regard to the a longitudinal axis A.

As shown in the schematic drawing of Fig. 53 showing a yet further kind of applicator 10, a front end 40 of the applicator head 14 can also comprise a single central hole di. This single central hole d1 can be formed additionally to or as an alternative to the plurality of holes d2.

Said one or more holes di, d2 can have a size selected in the range of 0.2 to 0.9, especially of 3 to 0.8 mm.

The applicator head 14 can comprise between one and 10000 holes di ; d2.

In the applicators 10 shown in Figs. 52, 53 and 55, the applicator head 12 comprises an application tip 14 that is made from a material different from a material of the elongate body part 16; 107. The application tip 14 covers the front end of the elongate body part and comprises bristles 26 extending from the base 56, with the base 56 overlapping a part of the elongate body part 16.

The base 56 may have a thickness selected in the range of 0.1 to 0.8 mm.

As indicated in Fig. 52, the respective applicator 10 of Figs. 52 and 53 may have a front end of the elongate body part 16 that is trapezoidal in shape, alternatively the shape can be cylindrical as indicated in Fig. 55.

The applicator 10 shown in connection with Fig. 54 is slightly different in this regard. The bristles 26, 106 are formed by injection molding the material of the bristles through a hollow front end 40 of the elongate body part 16 of the applicator 10. The bristles 26, 106 are guided through radial holes 107 in the injection molding process. The radial holes 107 are formed in a wall of the elongate body part forming the hollow front end 40.

The applicator 10 shown in Fig. 54 is thus formed by injection molding the material of the bristles through the hollow front end 40 of the elongate body part 16 in contrast to the applicators 10 of Figs. 52, 53 and 55 where the application tip 14 is overmolded over the elongate body part 16.

It should be noted that a material of the elongate body part 16 of Fig. 55 can be metal or a plastic material, with the holes 106 being provided in order to anchor the material of the application tip 14 to the elongate body part 16.

The front end 40 of the respective applicator 10 shown in the foregoing has a diameter da selected in the range of 0.2 to 1 .2 mm.

The herein described application tip 14, respectively the herein described applicator head 12 may respectively comprise and/or be made from a material selected from the group of members consisting of a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU), a thermoplastic vulcanizate (TPV), a thermoplastic olefin elastomer (TPO), polyethylene (PE), polypropylene (PP), poly vinyl chloride (PVC), polyurethane (PU), polystyrene (PS), silicone and combinations of the foregoing.

In a preferred embodiment, said application tip 14 and/or the applicator head 12 is made from or comprises silicone forming a main part of the application tip material respectively the applicator head material, wherein a polymer selected from the group of members consisting of a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU), a thermoplastic vulcanizate (TPV), a thermoplastic olefin elastomer (TPO), polyethylene (PE), polypropylene (PP), poly vinyl chloride (PVC), polyurethane (PU) and/or polystyrene (PS) forms a residual part of said application tip. For example, silicone may be present in the application tip in an amount of from 55 % by mass or more, in an amount of from 60 % by mass or more, in an amount of from 70 % by mass or more, in an amount of from 80 % by mass or more, or in an amount of from 90 % by mass or more, based on the total mass of the application tip. The residual part of the application tip may be present in the application tip in an amount of from 45 % by mass or more, in an amount of from 40 % by mass or more, in an amount of from 30 % by mass or more, in an amount of from 20 % by mass or more, or in an amount of from 10 % by mass or more, based on the total mass of the application tip.

In a more preferred embodiment, the application tip 14 is made from silicone only, i.e., consists of silicone rubber.

In a further preferred embodiment the applicator head 12 may comprise bristles made of silicone only, i.e. the bristles of the applicator head consist of the silicone rubber.

The silicone (also referred to as “silicone rubber” or “polysiloxane”) used herein e.g., for injection molding to form the application tip 14 or by the so-called moltru- sion process described in connection with Figs. 9 to 21 , may be selected from any suitable high temperature vulcanized (HTV) silicone rubber which is typically classified into two main groups, namely HCR (high consistency rubber) silicone rubber and LSR (liquid silicone rubber), respectively. HTV (high temperature vulcanized) silicone rubber types can crosslink under high temperature, such as in the range of from 100 °C to 250 °C.

Apart from HTV silicone rubbers, it is also possible to use RTV (room temperature vulcanized) silicone rubber e.g., for injection molding to form the application tip. One component systems (RTV-1 ) may be used which immediately cure when exposed to atmospheric moisture. However, for injection molding purposes as described herein, RTV-2 (two-component) systems can be more useful as they start to cure at room temperature shortly after mixing the two components, e.g., such as RTV-2 obtainable from the SILUPRAN® series from Wacker Chemie AG. The silicone may be formed from crosslinking reactions selected from the group consisting of addition curing, polycondensation, and peroxide initiated curing. Each one of these crosslinking reactions is well known to the person skilled in the art. Typically, in addition curing, the polymer contains vinyl groups and crosslinking agent contains Si-H groups; in peroxide-initiated curing, the polymer contains vinyl groups; and in condensation curing, a reaction between a, co- dihydroxypolydimethylsiloxanes and silicic acid esters takes place.

For RTV silicone rubbers (RTV-1 or RTV-2), condensation curing may be used as crosslinking reaction. For HTV silicone rubbers in general, peroxide initiated curing may be used as crosslinking reaction. For RTV-2 silicone rubbers, two- component LSR silicone rubbers and one-component HCR silicone rubbers, addition curing may be used as crosslinking reaction.

In a preferred embodiment, the silicone is an RTV-2 silicone rubber, or a liquid silicone rubber (LSR). LSRs are typically used as a two-component system to produce elastic parts by chemical reaction during injection molding, e.g., such as LSRs obtainable from the Silopren® series from Momentive.

An example of injection molding of a silicone rubber, e.g., LSR, to cure by way of addition curing may be as follows. The silicone rubber, e.g., LSR, may be supplied in the form of ready-to-use components (part A and part B) in equal amounts (A:B ratio = 1 :1) via hydraulic or pneumatic reciprocating pumps to a static mixer. For this transfer, a pressure in the range of 150 to 220 bar may be used. From the static mixer, the silicone typically passes to an injection unit. Before reaching said injection unit, the pressure of the material is usually reduced, e.g., to 30-70 bar. The injection unit often has just one feeding screw for processing the silicone rubber, therefore resulting in the proportion of compression being 1 :1 . The injection pressure normally ranges from 100 to 1000 bar with an injection time lying between 0.5 to 3.0 seconds before the cavity is completely filled. For vulcanization of the silicone rubber, a molding temperature of about 100 °C to 250 °C may be used.

As the injected silicone rubber is heated to a high temperature (about 100 °C to 250 °C), it typically swells and may force its way back through the injection nozzle. To prevent this, the nozzle may be held in the forward position under a holding pressure of about 50 bars until the material in the region of the gate starts to cure. Furthermore, post-curing of the vulcanized silicone may be useful in order to improve mechanical properties of the final application tip article. For example, during post-curing, said vulcanized silicone rubber may be subjected to about four (4) hours of heat treatment at e.g. at 200 °C in an oven with fresh air or oxygen supply.

Enumerated embodiments

1 . A method of production of a dental and/or medical applicator comprising a carrier body having monofilament bristles using a mold tool, the mold tool having channels for shaping and fixing the bristles to the carrier body, wherein the carrier body serves to permit a user to move the bristles in use, wherein, during injection or pressure molding, melt is introduced into the channels under pressure for forming the bristles, the method comprising the steps of: a) prefabricating the carrier body to fit to edges of the mold tool; b) disposing the carrier body in the mold tool upstream of the channels in such a fashion that a free cross-section of the channels is fully covered; and c) introducing, following step b), the melt with a sufficiently high mold pressure as to shoot-through the carrier body in a vicinity of the free cross-section of the channels thereby displacing carrier material, with the melt subsequently filling the channels, wherein the carrier body acts as a pressure holding barrier during injection molding of the melt up to a point in time at which penetration of the melt through the carrier body begins with the melt subsequently penetrating explosively into the channels to form the monofilament bristles and evenly displace carrier ma- terial around a foot of the bristles to fix the carrier body to the monofilaments and/or a method of making an applicator, the applicator comprising an applicator head and an elongate body part as a carrier, wherein the applicator head comprises bristles made from a different material than the elongate body part, wherein the bristles extend out of the elongate body part in the application tip through channels, the method comprising the steps of providing the elongate body part having the channels and introducing a melt of material of the bristles with a sufficiently high mold pressure as to shoot-through the elongate body part in a vicinity of the free cross-section of the channels thereby displacing carrier material, with the melt subsequently filling the channels, wherein the carrier body acts as a pressure holding barrier during injection molding of the melt up to a point in time at which penetration of the melt through the carrier body begins with the melt subsequently penetrating explosively into the channels to form the monofilament bristles and evenly displace carrier material around a foot of the bristles to fix the carrier body to the monofilaments.

2. The method of embodiment 1 , wherein carrier material, which is displaced by the melt upon penetration through the carrier body, is at least partially displaced into openings of the channels.

3. The method of embodiment 1 or embodiment 2, wherein carrier material, which is displaced upon penetration of the melt through the carrier body, is shaped into a collar projecting into openings of the channels.

4. The method one of embodiments 1 to 3, wherein carrier material, which is displaced by penetration of the melt through the carrier body, is shaped to generate a funnel-shaped hole. 5. The method of one of embodiments 1 to 4, wherein the channels forming the bristles have an enlargement in a vicinity of their openings for acceptance of carrier material to generate a collar.

6. The method of one of embodiments 1 to 5, wherein carrier material, which is displaced by the melt upon penetration through the carrier material, forms an alloy together with said melt.

7. The method of one of embodiments 1 to 6, wherein, prior to introduction onto walls of the mold, regions of the carrier covering openings in the channels are given materially weakened structures or have materially weakened structures.

8. The method of embodiment 7, wherein radially symmetric intended breaking locations are introduced onto the carrier body.

9. The method of one of embodiments 1 to 8, wherein prior to introduction of the carrier body onto mold walls, the carrier body is provided with a thickness in regions covering openings in the channels which is reduced compared to a thickness in remaining regions.

10. The method of one of embodiments 1 to 9, wherein at least one additional carrier, having aligned holes, is introduced into the molding tool upstream of the channels, wherein the carrier through which the melt penetrates is placed onto the additional carrier body to cover the holes.

1 1 . The method of one of embodiments 1 to 10, wherein the additional carrier, having aligned holes, is introduced into the molding tool upstream of the channels and the carrier, which is to be penetrated by the melt, is disposed between the additional carrier and openings in the channels. 12. The method of one of embodiments 1 to 11 , wherein the carrier body consists essentially of an organic or inorganic material.

13. The method of one of embodiments 1 to 12, wherein the carrier body acts as a pressure- holding barrier up to an internal mold pressure of between 1000 to 5000 bar.

14. The method of one of embodiments 1 to 13, wherein the carrier body is made from a foil.

15. The method of embodiment 14, wherein the foil is stretched.

16. The method of embodiment 14 or embodiment 15, wherein the carrier body is made from a metallic foil.

17. The method of one of embodiments 14 to 16, wherein the carrier body is made from a plastic foil.

18. The method of embodiment 17, wherein the carrier body is made from an elastomer foil.

19. The method of one of embodiments 14 to 18, wherein the foil has a thickness of preferentially ^1 mm.

20. The method of one of embodiments 1 to 19, wherein the carrier body is made from a plate.

21 . The method of embodiment 20, wherein the plate has a thickness of ^0.2 mm. 22. The method of one of embodiments 1 to 21 , wherein the carrier body is formed from two or more layers.

23. The method of embodiment 22, wherein at least one layer covers openings in the channels and at least one additional layer is provided with holes in correspondence with a configuration of the channels.

24. The method of embodiment 22 or embodiment 23, wherein the two or more layers are made from differing materials.

25. The method of one of embodiments 22 to 24, wherein the two or more layers have differing elasticities.

26. The method of one of embodiments 1 to 25, wherein the carrier body is introduced as a pre-fabricated, blown molded component.

27. The method of one of embodiments 1 to 26, wherein the carrier body is introduced as a pre-fabricated, injection molded component.

28. The method of one of embodiments 1 to 27, wherein the carrier body is introduced as a pre-fabricated, deep drawn component.

29. The method of one of embodiments 1 to 28, wherein the carrier body is introduced into a open mold tool as endless material and is cut to proper length prior to closing the mold tool.

30. The method of one of embodiments 1 to 29, wherein the carrier body having a desired size is introduced onto an endless support and is separated from the support in a vicinity of the mold tool. 31 . The method of one of embodiments 1 to 30, wherein material of the carrier body covering the free cross-section of the channels can be welded to material of the bristles.

32. The method of one of embodiments 1 to 31 , wherein plastics having differing mechanical properties and leading to formation of the bristles are introduced into the mold tool in sections.

33. The method of one of embodiments 1 to 32, wherein bristle-forming plastics having differing colors are introduced into the mold tool in sections.

34. The method of one of embodiments 1 to 33, wherein the carrier body is introduced into the mold tool in the form of a raw material or as a blank and is shaped onto a mold wall surrounding the free cross-section of the channels in response to the mold pressure of the melt generating the bristles and prior to the point in time at which the melt penetrates through the shaped carrier.

35. The method of one of embodiments 1 to 34, wherein the carrier body is introduced into the mold tool in the form of a raw material or as a blank and is subjected to fluid pressure in response to which it is shaped on mold walls surrounding the free cross-section of the channels and prior to a point in time at which the melt is introduced into the mold tool at a higher mold pressure.

36. The method of one of embodiments 1 to 35, wherein the carrier body and the melt forming the bristles are introduced into the mold tool using a sandwich injection molding procedure.

37. The method of embodiment 36, wherein the sandwich injection molding procedure is carried out as a single shot or twin-shot procedure. 38. The method of one of embodiments 1 to 37, wherein the carrier body is preformed using a GIT method (gas injection technology) or is introduced into the molding tool with subsequent injection of the melt for the bristles.

39. The method of one of embodiments 1 to 38, wherein the carrier body is preformed using a WIT method (water injection technology) or is introduced into the mold tool and the melt for the bristles is subsequently injected.

40. An applicator (10), in particular a dental applicator, optionally obtainable and/or obtained by a method according to one of embodiments 1 to 39, the applicator (10) comprising an applicator head (12) with an application tip (14) and an elongate body part (16), wherein the applicator (10) is made from two parts (16, 12) of different material and comprises two kinks (18, 20), with one of the two kinks (18) being arranged at a part of the applicator (10) where the two different parts (12,

16) at least partially overlap one another.

41 . The applicator (10) according to embodiment 1 , wherein one of the two parts made from a different material is the elongate body part (16) and the other of the two parts (16, 12) made from a different material is the applicator head (12), in particular wherein some of the applicator head (12) overlaps some of the elongate body part (16).

42. The applicator (10) according to embodiment 40 or embodiment 41 , wherein a cross-section of the elongate body part (16) along at least a majority of a length (L) of the elongate body part (16) is at least substantially formed by one of a triangle and a Reuleaux triangle.

43. The applicator (10) according to one of the preceding embodiments 40 to 42, wherein the application tip (14) comprises one of a brush (24) with bristles (26) and a foam (28); and/or wherein the application tip (14) is configured to store a liquid thereat. 44. The applicator (10) according to embodiment 43, wherein one the two kinks (18, 20) is arranged directly adjacent to that part of the elongate body part (16) that is formed at least substantially by the Reuleaux triangle.

45. The applicator (10) according to one of the preceding embodiments 40 to 44, wherein the application tip (14) is a brush (24) with bristles (26), with the brush (24) and bristles (26) being formed by at least one of a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU), a thermoplastic vulcanizate (TPV), and a thermoplastic olefin elastomer (TPO).

46. The applicator (10) according to one of the preceding embodiments 40 to 45, wherein the two kinks (18, 20) are configured to be bent in one direction, in particular in only direction, especially such that the application tip (14) faces upwardly relative to the elongate body part (16).

47. The applicator (10) according to one of the preceding embodiments 40 to 46, wherein at least one of the two kinks (18, 20) is configured as a peripherally extending groove (22), in particular wherein the groove (22) has a round, circular, oval, triangular cross-section transverse to a longitudinal axis (A) of the applicator (10).

48. The applicator (10) according to one of the preceding embodiments 40 to 47, wherein the applicator head (12) is made from a material different from the elongate body part (16).

49. The applicator (10) according to one of the preceding embodiments 40 to 44, wherein the elongate body part (16) is made from one of polypropylene (PP) and polylactide (PLA).

50. The applicator (10) according to one of the preceding embodiments 40 to 49, wherein the applicator head (12) comprises a material selected from the group of members consisting of a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU), a thermoplastic vulcanizate (TPV), a thermoplastic olefin elastomer (TPO), polyethylene (PE), polypropylene (PP), poly vinyl chloride (PVC), polyurethane (PU), polystyrene (PS) and combinations of the foregoing.

51 . The applicator (10) according to one of the preceding embodiments 40 to 50, wherein the applicator head (12) is configured to receive a part of the elongate body part (16).

52. The applicator (10) according to embodiment 51 , wherein the part of the elongate body part (16) received within the applicator head (12) comprises one or more centering elements (30, 32) in particular wherein two groups of centering elements (30, 32) are provided that are axially spaced apart from one another; and/or wherein one of the kinks (18) is arranged at that part of the applicator head (12) and that part of the elongate body part (16) that is received within the applicator head (12); and/or wherein the elongate body part comprises features (30, 32) providing a security against rotation for the applicator head (12) with respect to the elongate body part (16).

53. The applicator (10) according to one of the preceding embodiments 40 to 44 and 46 to 52, wherein the application tip (14) is a foam application tip (14) made from an open cell foam having pores (34).

54. The applicator (10) according to one of the preceding embodiments 1 to 53, further comprising an undulating surface (46).

55. The applicator (10) according to embodiment 54, wherein the undulating surface (46) is provided to cover between 5 and 30 %, preferably between 10 and 25%, of the outer surface of the elongate body part (16). 56. The applicator (10) according to embodiment 54 or embodiment 55, wherein the undulating surface comprises a plurality of peaks (52) and valleys (54).

57. The applicator (10) according to one of the preceding embodiments 40 to 56, wherein one or more first points of injection (48) are provided.

58. The applicator (10) according to embodiment 57, wherein the one or more first points of injection are provided at the elongate body part (16)

59. The applicator (10) according to one of embodiments 56 to 58 and embodiment 18 or embodiment 19, wherein one of the one or more first points of injection (48) is provided at the undulating surface (46).

60. The applicator (10) according to one of the preceding embodiments, wherein one or more second points of injection (50) are provided.

61 . The applicator (10) according to embodiment 60, wherein the one or more second points of injection (50) are provided at the applicator head (12).

62. The applicator (10) according to embodiment 60 or embodiment 61 , wherein the one or more second points of injection are provided at the kink (18) arranged at the applicator head (12).

Claims

1 . An applicator (10), in particular a dental applicator, the applicator comprising an applicator head (12) and an elongate body part (16), wherein the applicator head (12) comprises material or is made from material that is different material from a material of the elongate body part (16), wherein the applicator head comprises bristles (26; 106)extending from and optionally overlapping a part of the elongate body part (16, 107) , with one or more holes (di ; d2) extending through the application tip towards the elongate body part.

2. The applicator (10) of claim 1 , wherein said one or more holes (di ; d2) have a size selected in the range of 0.2 to 0.9, especially of 3 to 0.8 mm.

3. The applicator (10) of claim 1 or claim 2, wherein the applicator head (12) comprises between one and 10000 holes (di ; d2).

4. The applicator (10) of one of claims 1 to 3, wherein a front end (40) of the applicator head (12) comprises a single central hole (di).

5. The applicator (10) of claim 4, wherein the single central hole (di) has a size selected in the range of 0.2 to 0.8 mm.

6. The applicator (10) of one of claims 1 to 5, wherein the applicator head (12) comprises two or more radial holes (d2).

7. The applicator (10) of claim 6, wherein the two or more radial holes (d2) have a size selected in the range of 0.2 to 0.9, especially of 3 to 0.8 mm

8 An applicator (10), in particular a dental applicator, in particular the applicator of one of claims 1 to 7, the applicator (10) comprising an applicator head (12) and an elongate body part (16; 107), wherein the applicator head (12) comprises material or is made from material different from a material of the elongate body part (16; 107), wherein the applicator head (12) comprises bristles (26) extending from and overlapping a part of the elongate body part (16), wherein applicator head (12) comprises an application tip (14) comprising a base (56) and the bristles (26) extending from the base (56), with the base (56) having a thickness selected in the range of 0.1 to 0.8 mm.

9. The applicator of claim 6, wherein the part of the elongate body part (16) which is covered by the application tip (14) is trapezoidal in shape and or cylindrical in shape.

10. An applicator (10), in particular the dental applicator of one of claims 1 to 9, the applicator comprising an applicator head (12) with an application tip (14) and an elongate body part (16), wherein the application tip (14) is made from a material or comprises a material different from a material of the elongate body part (16), wherein the application tip (12) overlaps a part of the elongate body part or extends through a part of the elongate body part, wherein the elongate body part is made from one of PE, POM, ABS, PBT, PA, SB, PVC, PMMA, PS, PC, PPS, and metal and a material of the application tip is selected from the group of members consisting of a thermoplastic elastomer (TPE), a thermoplastic polyurethane (TPU), a thermoplastic vulcanizate (TPV), a thermoplastic olefin elastomer (TPO), polyethylene (PE), polypropylene (PP), poly vinyl chloride (PVC), polyurethane (PU), polystyrene (PS), silicone and combinations of the foregoing.

1 1 . The applicator of claim 10, wherein the application tip (12) is made from respectively comprises silicone having a higher degree of cross-linking with oxygen, silicone made by addition curing (where polymer contains vinyl groups and crosslinking agent contains Si-H groups), a silicone having peroxide (-initiated) curing (where the polymer contains vinyl groups, and a silicone made by condensation curing (between a, co- dihydroxypolydimethylsiloxanes and silicic acid esters).

12. The applicator (10) of one of claims 1 to 1 1 , wherein a front end (40) of the applicator has a diameter selected in the range of 0.2 to 1 .2 mm.

13. The applicator (10) of one of claims 1 to 12, wherein the applicator (10) is made from two parts (16, 12) of different material.

14. The applicator (10) of claim 13, wherein the elongate body part comprises a hollow front end as the first part with the application tip comprising bristles extending through holes in the hollow front end.

15. The applicator (10) of claim 13 or claim 14, wherein the elongate body part comprises a first kink.

16. The applicator (10) of claim 13, wherein the applicator (10) comprises second and first kinks (18, 20), with the second kink (18) being arranged at a part of the applicator (10) where the two different parts (12, 16) at least partially overlap one another.

17. The applicator (10) according to embodiment 13 or claim 16, wherein one of the two parts made from a different material is the elongate body part (16) and the other of the two parts (16, 12) made from a different material is the applicator head (12), in particular wherein some of the applicator head (12) overlaps some of the elongate body part (16).

18. The applicator (10) according to one of claims 1 to 17, wherein a crosssection of the elongate body part (16) along at least a majority of a length (L) of the elongate body part (16) is at least substantially formed by one of a triangle and a Reuleaux triangle.

19. The applicator (10) according to claim 18 and one of claims 15 to 17, wherein said first kink (20) is arranged directly adjacent to that part of the elongate body part (16) that is formed at least substantially by the Reuleaux triangle.

20. The applicator (10) according to one of the preceding claims 1 to 19, wherein the applicator head (12) comprises one of a brush (24) with bristles (26) and a foam (28); and/or wherein the applicator head (12) is configured to store a liquid thereat.

21 . The applicator (10) according to one of the preceding claims 15 to 20, wherein the first and second kinks (20, 18) are configured to be bent in one direction, in particular in only direction, especially such that the application tip (14) faces upwardly relative to the elongate body part (16).

22. The applicator (10) according to one of the preceding claims 20 to 21 , wherein at least one of the the first and second kinks (20, 18) is configured as a peripherally extending groove (22), in particular wherein the groove (22) has a round, circular, oval, triangular cross-section transverse to a longitudinal axis (A) of the applicator (10).

23. The applicator (10) according to one of the preceding claims 1 to 22, wherein the applicator head (12) is configured to receive a part of the elongate body part (16).

24. The applicator (10) according to claim 22, wherein the part of the elongate body part (16) received within the applicator head (12) comprises one or more centering elements (30, 32) in particular wherein two groups of centering elements (30, 32) are provided that are axially spaced apart from one another; and/or wherein one of the kinks (18) is arranged at that part of the applicator head (12) and that part of the elongate body part (16) that is received within the applicator head (12).

25. The applicator (10) according to one of claims 1 to 24, wherein the elongate body part comprises features (30, 32) providing a security against rotation for the applicator head (12) with respect to the elongate body part (16).

26. The applicator (10) according to one of the preceding claims 1 to 25, further comprising an undulating surface (46).

27. The applicator (10) according to claim 26, wherein the undulating surface (46) is provided to cover between 5 and 30 %, preferably between 10 and 25%, of the outer surface of the elongate body part (16).

28. The applicator (10) according to claim 26 or claim 27, wherein the undulating surface comprises a plurality of peaks (52) and valleys (54).

29. The applicator (10) according to one of the preceding claims 1 to 28, wherein one or more first points of injection (48) are provided.

30. The applicator (10) according to claim 29, wherein the one or more first points of injection are provided at the elongate body part (16)

31 . The applicator (10) according to one of claims 26 to 28 and claim 30 or claim 31 , wherein one of the one or more first points of injection (48) is provided at the undulating surface (46).

32. The applicator (10) according to one of the preceding claims, wherein one or more second points of injection (50) are provided.

33. The applicator (10) according to claim 60, wherein the one or more second points of injection (50) are provided at the applicator head (12).

34. The applicator (10) according to claim 60 or claim 61 , wherein the one or more second points of injection are provided at the second kink (18) arranged at the applicator head (12).

35. The applicator (10) according to claim 33, wherein the second point of injection is formed in a front hollow end of the elongate body part, with the front hollow end comprising holes.

36. A method of making an applicator (10), such as an applicator in accordance with one or more of the preceding claims 1 to 35, the applicator comprising an applicator head (12) and an elongate body (16) part as a carrier, wherein the applicator head (12) comprises bristles (26; 107) made from a different material than the elongate body part, wherein the bristles extend out of the elongate body part in the application tip through channels, the method comprising the steps of providing the elongate body part having the channels and introducing a melt of material of the bristles with a sufficiently high mold pressure as to shoot-through the elongate body part in a vicinity of the free cross-section of the channels thereby displacing carrier material, with the melt subsequently filling the channels, wherein the carrier body acts as a pressure holding barrier during injection molding of the melt up to a point in time at which penetration of the melt through the carrier body begins with the melt subsequently penetrating explosively into the channels to form the monofilament bristles and evenly displace carrier material around a foot of the bristles to fix the carrier body to the monofilaments.

37. The method of claim 36 , wherein the step of providing the bristles at the elongate body part comprises forming the applicator head at the elongate body part.

38. The method of claim 36 or claim 37, the method further comprising the step of injecting a material of the application tip through the elongate body part.

39. The method of one of claims 36 to 38, wherein the application tip is formed by from plastic melt by injection molding in bristle forming channels.