The present invention relates to a capsule for low and/or high viscosity com pounds, in particular liquid compounds and/or compounds with a viscosity be tween water and honey, preferably for dental compounds, with a housing, the housing comprising a storage section with a storage volume for a storage of the compound and an application section with an application channel for an applica tion of the compound, wherein the storage volume comprises a filling end and a discharging end and the application channel comprises a storage end and an ap plication end, wherein the storage volume comprises an essentially cylindrical middle section located between the filling end and the discharging end to provide a piston guide for a piston inserted into the storage volume, wherein the discharging end of the storage volume and the storage end of the application channel are con nected in a fluid communicating way, wherein the filling end of the storage volume is placed at a filling opening of this housing and is accessible from outside of the housing for a filling of the storage volume with the compound, wherein the applica tion end of the application channel is placed at an application opening of the hous ing and is accessible from outside of the housing for an application of the com pound. Further, the present invention relates to a piston for a usage with such a capsule, wherein the piston is adapted to be inserted into the storage volume, wherein a compound in the storage volume is forceable into the application chan nel by a movement of the piston in the storage volume towards the application end of the storage volume, and wherein the piston forms a closing means to be insert ed into the filling opening of the housing of the capsule. In addition, the present invention is related to a system comprising such a capsule and preferably such a piston.

Capsules are commonly used for storage and application of compounds of various viscosities. Capsules often comprise a storage volume, in which the compound in question can be stored. A piston inserted into the capsule, especially into the stor age volume of the capsule, can be used to force the compound into and/or through an application channel of the capsule for an application of the compound. Espe cially dental compounds can be stored in and applicated by such capsules. A sys tem comprising a capsule and a piston for instance can be inserted into a respec tive composite gun, wherein the composite gun can actuate the piston and there fore trigger the actual application procedure.

During filling of a capsule with a compound, storage of a filled capsule and appli cation of the compound, a sealing of the capsule, especially of a filling opening of the capsule, has to be provided. Without sealing, the compound filled into and/or stored in the capsule can leak out of the capsule. Also air can enter the capsule, especially the storage volume of the capsule, and reduce the lifetime of the com pound stored therein. Additionally, also a contamination of the compound filled into and/or stored in the capsule is possible. Especially for low viscosity compounds, for instance liquids, a reliable sealing has to be provided.

In addition and especially for high viscosity compounds, a planar application of the compound is favorable. To achieve this, it is known to provide specially formed brush tips as additional attachments for application sections of capsules. For the planar application, these additional attachments have to be connected to the ap plication opening of the housing of the capsules in an additional manufacturing step. Further, sealing issues at the transition from the capsule to the additional attachment often cannot be avoided. In view of the above, it is an object of the present invention to provide an improved capsule, an improved piston and an improved system, which do not have the aforementioned drawbacks of the state of the art. In particular, it is an object of the present invention to provide a capsule, a piston and a system for low viscosity compounds, which comprise an improved sealing in an especially easy and cost- efficient way. Further, it is an alternative or additional object of the present inven tion to provide a capsule, a piston and a system for high viscosity compounds, which allow and provide an improved planar application of the high viscosity com pound in an easy and cost efficient way.

This object is satisfied by the patent claims. In particular, this object is satisfied by a capsule for low viscosity compounds according to claim 1 , by a piston for a us age with a capsule according claim 20, by a system comprising a capsule and pis ton according to claim 26 and by a method for producing a capsule according to claim 29. The dependent claims describe preferred embodiments of the invention. Details and advantages described with respect to a capsule according to the first aspect of the invention also hold true for a piston according to the second aspect of the invention, for a system according to the third aspect of the invention and for a method according to the forth aspect of the invention and vice versa, if of tech nical sense.

According to a first aspect of the invention, the object is satisfied by a capsule for low viscosity compounds, in particular liquid compounds, preferably for dental compounds, with a housing, the housing comprising a storage section with a stor age volume for a storage of the compound and an application section with an ap plication channel for an application of the compound, wherein the storage volume comprises a filling end and a discharging end and the application channel com prises a storage end and an application end, wherein the storage volume compris es an essentially cylindrical middle section located between the filling end and the discharging end to provide a piston guide for a piston inserted into the storage vol- ume, wherein the discharging end of the storage volume and the storage end of the application channel are connected in a fluid communicating way, wherein the filling end of the storage volume is placed at a filing opening of the housing and is accessible from outside of the housing for a filling of the storage volume with the compound, wherein the application end of the application channel is placed at an application opening of the housing and is accessible from outside of the housing for an application of the compound. A capsule according to the invention is charac terized in that an inner surface of the storage volume comprises first sealing means at and/or near the filling end of the storage volume for providing a seal of the storage volume with respect to a closing means inserted into the filling opening of the housing, wherein the first sealing means comprise one or more, in particular two or more, preferably three or more, circumferential protrusions projecting from the inner surface toward a longitudinal axis of the storage section.

This first embodiment of a capsule according to the invention can be used for a storage and/or application of especially low viscosity compounds, in particular liq uid compounds, preferably dental compounds. The respective compound can be filled into a storage volume through a filling opening of the housing of the capsule. The storage volume is located in a storage section of the capsule, wherein the storage volume comprises a filling end at the filling opening of the housing. The main part of the storage volume is a middle section of the storage volume, which is preferably essentially cylindrically shaped. This cylindrical shape allows a guid ance of a piston within the storage volume, essentially beginning at the filling end of the storage volume towards a discharging end of the storage volume.

Connected to the discharging end of the storage volume in a fluid communicating way is a storage end of an application channel of an application section of the housing of the capsule. The compound can be forced by a movement of the piston via the discharging end of the storage volume into the storage end of the applica tion channel, through the application channel and out of an application end of the application channel. This application end of the application channel placed at an application opening of the housing, preferably the application end is essentially identical to the application opening of the housing. An application of the compound stored in the storage volume of the capsule via an application opening, for in stance onto a tooth of a patient, can therefore be provided.

To prevent leaking out of the compound filled into the storage volume and also of a possible contamination of the compound in the storage volume, a sealing of the storage volume, especially of the filling end of the storage volume and/or the filling opening of the housing, against a closing means inserted into the filling opening and the filling end, respectively, is necessary.

According to the invention, first sealing means are comprised at an inner surface of the storage volume at and/or near the filling end of the storage volume. These first sealing means can provide a sealing of the storage volume against a closing means inserted into the filling opening of the housing and/or into the filling end of the storage volume. According to the invention, these first sealing means are part of the housing of the capsule. Therefore, the first sealing means arranged at the inner surface of the storage volume allow a sealing against any closing means inserted into the filling opening of the housing and/or the filling end of the storage volume. Especially, the sealing can be provided for instance already during the filling of the storage volume of the capsule, in which a filling nozzle of a filling ap paratus is inserted into the filling opening of the housing as a closing means. After that, the first sealing means arranged at the inner surface of the storage volume comprise a sealing against a piston inserted as a closing means into the filling opening of the housing, for instance for a storage of the filled capsule. Separate sealing means, provided as part of each of the different closing means, can there fore be avoided. Preferably, the first sealing means according to the invention comprise one or more, in particular two or more, preferably three or more, circumferential protru sions at the inner surface. These protrusions can for instance comprise an at least partly circular and/or elliptical cross section. Additionally or alternatively, the pro trusions can also be formed as sealing lips. As the storage volume often compris es a circular cross section, see for instance the essentially cylindrical middle sec tion or also conical parts of the storage volume placed and/or near the filling end of the storage volume, a circumferential protrusion and comprise a continuous seal ing along the edge of the storage volume. The overall sealing of the storage vol ume can therefore be improved. By providing more than one, in particular more than two, preferably more than three protrusions, the resulting sealing provided by a capsule according to the invention can further be improved.

In summary, a capsule according to the invention can provide an improved sealing of a filling opening of the housing of the capsule and/or of a filling end of the stor age volume of the capsule. Especially, by providing first sealing means at an inner surface of the storage volume, the sealing of the storage volume can be provided independently from the respective closing means inserted into the filling opening of the housing.

According to another embodiment according to the first aspect of the invention, the object is satisfied by a capsule for high viscosity compounds, in particular com pounds with a viscosity between water and honey, preferably for dental com pounds, preferably in accordance with a capsule according for low viscosity as described above, with a housing, the housing comprising a storage section with a storage volume for a storage of the compound and an application section with an application channel for an application of the compound, wherein the storage vol ume comprises a filling end and a discharging end and the application channel comprises a storage end and an application end, wherein the storage volume comprises an essentially cylindrical middle section located between the filling end and the discharging end to provide a piston guide for a piston inserted into the storage volume, wherein the discharging end of the storage volume and the stor age end of the application channel are connected in a fluid communicating way, wherein the filling end of the storage volume is placed at a filing opening of the housing and is accessible from outside of the housing for a filling of the storage volume with the compound, wherein the application end of the application channel is placed at an application opening of the housing and is accessible from outside of the housing for an application of the compound. A capsule according to the in vention is characterized in that the application section comprises a brush tip at the application end of the application channel.

This second embodiment of a capsule according to the invention can be used for a storage and/or application of especially high viscosity compounds, in particular compounds with a viscosity between water and honey, especially honey-like com pounds, preferably dental compounds. The respective compound can be filled into a storage volume through a filling opening of the housing of the capsule. The stor age volume is located in a storage section of the capsule, wherein the storage vol ume comprises a filling end at the filling opening of the housing. The main part of the storage volume is a middle section of the storage volume, which is preferably essentially cylindrically shaped. This cylindrical shape allows a guidance of a pis ton within the storage volume, essentially beginning at the filling end of the storage volume towards a discharging end of the storage volume.

Preferably the second embodiment of a capsule according to the present invention is constructed in accordance with the features described above with respect to the first embodiment of a capsule according to the present invention.

Connected to the discharging end of the storage volume in a fluid communicating way is a storage end of an application channel of an application section of the housing of the capsule. The compound can be forced by a movement of the piston via the discharging end of the storage volume into the storage end of the applica tion channel, through the application channel and out of an application end of the application channel. This application end of the application channel placed at an application opening of the housing, preferably the application end is essentially identical to the application opening of the housing. An application of the compound stored in the storage volume of the capsule via an application opening, for in stance onto a tooth of a patient, can therefore be provided.

According to the invention, the application section of the capsule comprises a brush tip at the application end of the application channel. In other words, the brush tip is a part, preferably an intrinsic part, of the application section. Therefore, the application section of the capsule according to the invention itself can provide a planar application of the high viscosity compound. Especially, an additional step to attach an attachment comprising a brush separate from the capsule is not nec essary. The high viscosity compound leaves the capsule according to the inven tion through the application end of the application channel and is spread onto a target surface in a planar way by the brush tip. Providing a planar application of the high viscosity compound onto a target surface can therefore be simplified.

Further, a first embodiment of a capsule according to the invention can be charac terized in that the application section comprises a brush tip at the application end of the application channel. All advantages described with respect to the second embodiment of a capsule according to the present invention can therefore be pro vided by a first embodiment of a capsule according to the present invention pro vided with a brush tip at its application end.

Preferably, a capsule according to the invention can be improved by that the first sealing means and the inner surface of the storage volume, in particular the stor age section, preferably the housing, are composed of the same material. By using the same material for the first sealing means and at least the inner surface of the storage volume, a production of a capsule according to the invention can be sim plified. The number of necessary production steps for manufacturing the sealing means and the inner surface, the storage volume and/or the housing, respectively, can be minimized or at least be drastically reduced. Especially, for instance a molding process, especially an injection molding process, can be used to produce the capsule including the first sealing means in a single production step.

Additionally, a capsule according to the invention can be characterized in that the housing is composed of at least one of the following plastic materials, wherein the plastic material is of medical grade:

- Polybutylene terephthalate (PBT)

- Polymethyl methacrylate (PMMA)

- Polyamide (PA)

- Cyclic olefin copolymer (COC)

- Cyclic olefin polymer (COP)

As a capsule according to the invention is often used for dental compounds, it is necessary that a reaction between the material of the capsule, especially the ma terial of the storage volume, and the compound filled into and/or stored in the stor age volume can be prohibited. By using a medical grade plastic material for the housing, such an interaction between the material of the housing and the com pound stored in the storage volume can be avoided. The listed plastic materials have in common that they are firm and rigid. Hence sharp edges and/or defined outlines of the capsule needed for spraying the low viscosity compound can easily be provided.

Further, a capsule according to the invention can be characterized in that a mate rial of the brush tip is softer than a material of the housing. The brush tip is used to applicate the high viscosity compound onto the target surface. This procedure of ten includes a direct physical contact of the brush tip and the target surface. By using a soft material for the brush tip, especially a material softer as the material used for housing, a certain flexibility of the brush tip can be provided and therefore harming of the target surface can be prohibited. In addition, a soft material of the brush tip can allow a certain deformation of the brush tip upon contact with the target surface. The size of the planar application provided by the brush tip can therefore be easily adjusted. In contrary to that, the housing should be more rigid and especially not easily deformable. By composing the housing out of a material harder than the brush tip, this rigidness of the housing can easily be provided.

Additionally, a capsule according to the invention can be improved by that the ma terial of the brush tip has a hardness measured with the Shore A Durometer se lected in the range of 20A to 95A and up to a hardness measured with the Shore D Durometer of 55D, preferably in the range of 20A to 50A. This wide range of softness allows choosing a brush tip according to the respective requirements. Softer brush tips, especially with a hardness measured with the Shore A Durome ter selected in the range of 20A to 50A, can be used for delicate surfaces, for in stance a tooth of a patient. Alternatively or additionally, a housing of the capsule, especially the storage section of the capsule, has a hardness measured with the Shore A Durometer selected in the range of 25A to 95A and up to a hardness measured with the Shore D Durometer of 75D, preferably in the range of 70A to 75D. This wide range of more rigid material allows choosing a housing, especially a storage section of the housing, according to the respective requirements. Espe cially, rigid and durable housings can be provided.

Especially, a capsule according to the invention can be characterized in that the brush tip is composed of a thermoplastic elastomer (TPE), in particular a medical grade TPE, and/or an ethylene vinyl acetate (EVA), in particular a medical grade ethylene vinyl acetate (EVA), with a hardness measured with the Shore A Du rometer from 20A to 95A and up to a hardness measured with the Shore D Du rometer of 55D, preferably in the range of 20A to 50A, and/or the housing is com posed of medical grade thermoplastic elastomer (TPE) and/or medical grade eth- ylene vinyl acetate (EVA).. Typical examples of soft materials, especially soft plas tic materials, are TPE (thermoplastic elastomers or thermoplastic rubbers) and EVA (ethylene vinyl acetate). TPE and EVA typically have a hardness measured on the“A” scale from 20 Shore“A” to 95 Shore“A”, with some harder TPE materi als, i.e. materials harder than 90 Shore“A” typically being measured on the“D” scale up to a hardness of 55D. Further, by using medical grade thermoplastic elas tomer and/or medial grade ethylene vinyl acetate as material for the brush tip, an interaction between the material of the brush tip and the compound applicated by the brush tip volume can be avoided. As already described above, a capsule ac cording to the invention is often used for dental compounds. Therefore it is neces sary that also a reaction between the material of the capsule, especially the mate rial of the storage volume, and the compound filled into and/or stored in the stor age volume can be prohibited. By using medical grade thermoplastic elastomer and/or medial grade ethylene vinyl acetate as material for the housing, such an interaction between the material of the housing and the compound stored in the storage volume can be avoided.

Further, in a preferred embodiment of the invention, a capsule according to the invention can be characterized in that the housing and the brush tip are produced in a 2-component injection molding process. In a 2-component injection molding process, two, preferably different, materials are used during the molding, either simultaneously or consecutively. As a result, a single component can be produced, wherein different sections of this component can be made up of different materials. For an example, a brush tip made up of a softer material can be combined with a housing made up of a more rigid material. Additionally, a secure fixing of the brush tip on the housing can easily be provided, for instance due to grooves and/or un dercuts in the housing filled with material of the brush tip during an injection mold ing process of the brush tip onto the housing. Further on, 2-component molding is a fast, easy and cost efficient production method. Further, a capsule according to the invention can be characterized in that the ap plication section comprises application sealing means for providing a sealing of the application channel, preferably placed at and/or near the application end of the application channel. The first sealing means of a capsule according to the inven tion can provide a sealing against a closing means inserted into the filling opening of the housing. As described above, a capsule according to the invention compris es a continuous channel, starting at the filling end of the storage volume, continu ing by the fluidly connected discharging end of the storage volume and storage end of the application channel and ending at the application end of the application channel. Providing application sealing means at the application section, preferably placed at and/or near the application end of the application channel, a sealing of the second end of the aforementioned continuous channel within the capsule ac cording to the invention can be provided. A prevention of a leaking out and/or a contamination of the compound stored in the storage volume of the capsule can therefore be improved.

A capsule according to the invention can further be improved by that the applica tion sealing means comprise at least one of the following items:

welding seem

heat sealing

cap

plug

foil cover.

This list is open and also other items can be used for application sealing means if these make technical sense. Especially, an application sealing means adapted to the embodiment of the application end of the application channel can be chosen.

Further, a capsule according to the invention can be improved by that the foil cov er comprises a multi-component foil. In such a multi-component foil, different foil elements with different features can be combined into a single multi-component foil. Each of the foil elements of the multi-component foil can provide different and especially specialized features. For instance, one of the components can be light proof, another component can be tight, especially vapor tight, and, preferably the innermost component which will be in contact with the application opening, can be of a medical grade. Therefore, especially a foil cover adapted to the compound stored in the storage volume of the capsule can be provided.

Preferably, a capsule according to the invention can be improved by that the appli cation sealing means, in particular the cap and/or the plug and/or the foil cover, are at least partly made of polybutylene terephthalate (PBT) and/or at least partly made of cyclic olefin polymer (COP), in particular of cyclic olefin copolymer (COC). Polybutylene terephthalate, cyclic olefin polymer and/or cyclic olefin copolymers are especially easy to handle and can easily be produced in several shapes and adapted to the special needs of the respective application sealing means. There fore these materials are especially preferred to be used as materials of at least parts of the application sealing means.

In another embodiment of a capsule according to the invention, the capsule can be characterized in that the storage volume comprises a cardinal volume orientation and the application channel comprises a cardinal channel orientation, and wherein the cardinal volume orientation angles the cardinal channel orientation at an angle between 10° and 60°. The cardinal volume orientation can preferably be identical or at least almost identical to the longitudinal axis. In other words, a direction of the application channel present at the application end of the application channel is preferably different to the direction of the storage volume present at its filling end. This allows during an application of a compound using a capsule according to the invention to reach target surfaces which otherwise, especially with completely aligned cardinal orientations of the storage volume and the application channel, are impossible to be reached. Especially for dental compounds this allows to easi ly reach all or at least essentially all areas within a mouth of a patient.

The first sealing means may comprise one or more, in particular two or more, preferably three or more, circumferentially extending sealing lips. Such sealing lips can be manufactured in a simple manner during the process of making the cap sule.

The sealing lip may be formed either by integrally forming the sealing lip from the same material as that of the capsule or by forming the sealing lip from a further material. The sealing lips may have a rounded shape projecting from the inner sur face toward a longitudinal axis of the storage section. In this way an improved seal can be made available between the piston and the capsule.

The sealing lips may have a part circular cross-section in a plane perpendicular to the inner surface. Such shapes are simple to manufacture e.g. in an injection molding process.

The size of the sealing lip generally depends on the shape, size and material of the piston respectively of the capsule. The size may be selected such that the sealing lip projects by at most 2 mm from the inner surface of the capsule, prefer ably by 0.2 to 1.5 mm especially by 0.4 to 1.2 mm from the inner surface of the capsule to ensure a seal between the capsule and the piston.

The brush tip may comprise a plurality of bristles, optionally with the brush tip re spectively the plurality of bristles having an outer diameter of less than 4 mm, preferably an outer diameter selected in the range of 1 to 3 mm, especially of 1.5 to 2.5 mm; and/or optionally with the brush tip respectively the plurality of bristles having a length projecting from the application end of the application channel se lected in the range of 1.5 to 10 mm, preferably of 2 to 7 mm and especially of 3 to 6 mm; and/or optionally with each bristle of the plurality of bristles having a diame ter selected in the range of 0.01 to 1 mm, especially of 0.05 to 0.5 mm; and/or op tionally with the plurality of bristles comprising between 4 and 150 bristles. The size and number of each bristle of the plurality of bristles is typically selected in dependence on the precise application, with lesser bristles being selected for higher viscosity components than for low viscosity components that may be stored in the capsule.

According to a second aspect of the invention, the object is satisfied by a piston for a usage with a capsule according to the first aspect of the invention, wherein the piston is adapted to be inserted into the storage volume, and wherein a compound in the storage volume is forceable into the application channel by a movement of the piston in the storage volume towards the application end of the storage vol ume.

A piston according to the second aspect of the invention is intended to be used in and/or with a capsule according to the first aspect of the invention. Therefore a piston according to the second aspect of the invention can provide all features and advantages already described in detail with respect to a capsule according to the first aspect of the invention.

As a piston according to the second aspect of the invention can be used in and/or within a capsule according to the first aspect of the invention, in other words the storage volume of the capsule forms a piston guide to guide the piston according to the second aspect of the invention within the storage volume. A movement of the piston through the storage volume from the filling end of the storage volume towards the discharging end of the storage volume forces a compound stored in the storage volume through the discharging end of the storage volume via the storage end of the application channel into the application channel and later on out of the application end of the application channel for an application of the com- pound, in particular using the brush tip of the capsule. The movement of the piston within the storage volume of the capsule can for instance be actuated by a stand ard composite gun.

Preferably, the piston according to the second aspect of the invention forms a closing means to be inserted into the filling opening of the housing of the capsule according to the first aspect of the invention. In other words, the first sealing means arranged at the inner surface of the storage volume of the capsule accord ing to the first aspect of the invention seal the storage volume by contacting the piston inserted into the filling opening as closing means. A secure and tight sealing of the filling end of the storage volume and/or the filling opening of the housing of the capsule according to the first aspect of the invention can therefore be provid ed.

Preferably, a piston according to the invention comprises second sealing means to engage the first sealing means for a sealing of the storage volume. This second sealing means are preferably that part of the piston which can contact the first sealing means of the capsule. An overall sealing of the filing end of the storage volume and/or the filling opening of the housing can therefore be improved.

In a preferred embodiment of a piston according to the invention, the second seal ing means are a circumferential sealing surface of the piston. For instance, a pis ton according to the invention can be essentially of a cylindrical shape, wherein the side of the cylinder provides at least partly a circumferential sealing surface.

By providing a circumferential sealing surface it can be ensured that the circum ferential protrusions as part of the first sealing means completely contact the sec ond sealing means, especially the circumferential sealing surface, of the piston. A further improvement or at least an overall simplification of the sealing provided at the filling end of the storage volume and/or the filling opening of the housing can therefore be provided. Additionally, a piston according to the invention can be characterized in that the piston comprises a venting hole, in particular a sealable venting hole. As the piston is inserted into the filling opening of the housing, it is possible, that air is confined between the piston and compound already filled into the storage volume. A venting hole as part of the piston allows this air to escape during an insertion of the piston into the filling opening of the housing. Especially, the air has not to escape through the sealing provided by the first and if present second sealing means. After com pletion of the insertion of the piston into the filling opening, the venting hole itself can be sealed, for instance with a foil cover, a plug, by gluing and/or by welding.

Further, a piston according to the invention can be characterized in that the piston is at least partly made of polybutylene terephthalate (PBT) and/or at least partly made of cyclic olefin polymer (COP), in particular of cyclic olefin copolymer (COC). As already mentioned above, these particular materials are easy to handle and can be provided easily in different shapes.

In a third aspect of the invention, the object is satisfied by a system comprising a capsule and a piston, wherein the capsule is provided according to the first aspect of the invention and preferably the piston is provided according to the second as pect of the invention. By providing a capsule according to the first aspect of the invention and/or a piston according to the second aspect of the invention, a sys tem according to the third aspect of the invention can provide all features and ad vantages which are described above in detail according to a capsule according to the first aspect of the invention and/or a piston according to the second aspect of the invention.

Further, a system according to the invention can be characterized in that the stor age volume of the capsule contains a low viscosity compound, in particular a liquid compound, preferably a dental compound, wherein the filling opening of the hous- ing is sealingly closed by the piston. As a system according to the third aspect of the invention comprises a capsule according to the first aspect of the invention, first sealing means are present at an inner surface of the storage volume of the capsule. By inserting a piston into the filling opening, the piston acts as closing means and engages with the first sealing means and therefore a sealing can be provided. The low viscosity compound, in particular the liquid compound, prefera bly the dental compound, is sealing confined within a system according to the in vention. Especially a leaking of the compound out of the system and/or a contami nation of the compound already filled into the capsule of the system can be prohib ited.

Alternatively, a system according to the invention can be characterized in that the storage volume of the capsule contains a high viscosity compound, in particular a compound with a viscosity between water and honey, preferably a dental com pound, wherein the filling opening of the housing is sealingly closed by the piston. As a system according to the third aspect of the invention comprises a capsule according to the first aspect of the invention, a brush tip is comprised at the appli cation end of the housing of the capsule. The high viscosity compound, in particu lar the compound with a viscosity between water and honey, preferably the dental compound, can therefore be applicated easily in a planar way. By sealingly closing the filling end of the storage volume and/or the filling opening of the housing, a leaking of the compound out of the system and/or a contamination of the com pound already filled into the capsule of the system can be prohibited.

In a forth aspect of the invention, the object is satisfied by a method of producing a capsule with a brush tip, preferably a capsule in accordance with the first aspect of the invention, the method comprising the steps of:

- providing a mold for the brush tip of the capsule and injection molding the brush tip in situ; - providing a mold for the remnants of the capsule with the molded brush tip in situ and injection molding the capsule from a material different from the brush tip.

A method according to the forth aspect of the invention is preferably intended to provide a capsule according to the first aspect of the invention. Therefore, in this preferred embodiment, a method according to the forth aspect of the invention can provide all features and advantages already described in detail with respect to a capsule according to the first aspect of the invention.

A method according to the invention is used for producing capsules with a brush tip. Essentially, the capsule including the brush tip is produced using a molding process. For the brush tip and the remaining parts of the capsule, different materi als are used. Preferably, the brush tip is molded from a softer material than the remnants of the capsule, especially a storage section and/or an application section of the housing of the capsule. Therefore, a method according to the invention es sentially comprises a 2-component molding process.

According to a first step of a method according to the invention, a mold is provided for the brush tip and subsequently the brush tip is injection molded using this brush tip mold. In other words, after the first step the brush tip of the capsule can already be provided.

In a second step of a method according to the invention, a mold is provided for the remnants of the capsule, wherein especially in this capsule mold the already molded brush tip is inserted. Subsequently, the remaining parts of the capsule are injection molded, wherein a material different of the brush tip is used. During this second molding process, the material of the remnant of the capsule preferably at least partly encloses the brush tip and/or connects to the material of the brush tip to provide a secure and/or resistant interconnection of these two parts of the cap sule produced in a method according to the invention.

In the second step, different molds can be used for molding of the brush tip and of the remnants of the capsule, respectively. Alternatively, also a single mold can be used, wherein this single mold is internally changed between the two steps of a method according to the invention, for instance by moving and/or removing of spacers in this single mold.

The method according to the invention is described with respect to a production of a single capsule. Apparently, the method according to the invention can easily be adapted to produce two or more capsules with brush tips simultaneously.

Within the scope of the present invention, the order of the two steps of a method according to the invention can be swapped. In other words, a method according to the invention can alternatively comprise the steps of:

- providing a mold for the remnants of the capsule without the brush tip of and injection molding the remnants of the capsule in situ;

- providing a mold for brush tip with the molded remnants of the capsule in situ and injection molding the brush tip from a material different from the remnants of the capsule.

All features and advantages described above are also valid for this swapped ver sion of the method according to the invention, wherein references to the brush tip and the remnants of the capsule, respectively, are accordingly swapped. Also in this embodiment of a method according to the invention, preferably the material used to mold the brush tip is softer than the material used to mold the remaining parts of the capsule. The present invention is further described hereinafter with reference to illustrated embodiments shown in the accompanying drawings.

There is shown:

Fig. 1 a sectional view of a system with a first embodiment of a capsule according to the invention,

Fig. 2 an isometric view of a system with a first embodiment of a capsule according to the invention,

Fig. 3 a sectional view of a system with a second embodiment of a capsule according to the invention, and

Fig. 4 an isometric view of a system with a second embodiment of a capsule according to the invention.

Elements of the same function are specified throughout the figures with the same reference signs. In the following, any statement made having regard to the direc tion of a component is made relative to the position in the drawing and can natural ly wherein the actual position. The description of the accompanying drawing is on ly by the way of detail. Specific features of each aspect of the present invention and of the figures can be combined with each other if of technical sense.

Fig. 1 shows a system 100 according to the present invention with a first embodi ment of a capsule 10 in a sectional view. The system 100 at least comprises a capsule 10 according to the invention and, as shown in Fig. 1 , preferably also a piston 60 according to the invention. The system 100, especially the capsule 10, is used to store and to applicate compounds 102, especially low viscosity com- pounds 102, preferably compounds 102 for dental applications. These compounds 102 can be stored in a storage volume 32 of a storage section 30.

The storage section 30 is part of the housing 20 of the capsule 10. The compound 102 is stored in an essentially cylindrical middle section 34 of the storage volume 32, the storage section 30 and the storage volume 32 having a longitudinal axis 46. The longitudinal axis 46 can preferably be identical or at least almost identical to the cardinal volume orientation 80. For a filing of the storage volume 32, a filling opening 22 in the housing 20 and respectively a filling end 36 of the storage vol ume 32 is used. The compound 102 is inserted into the storage volume 32 and can fill the storage volume 32 essentially from is its filling end 36 up to its discharg ing end 38.

The discharging end 38 of the storage volume is connected to a storage end 54 of an application channel 52 of a capsule 10 in a fluid communication way. The ap plication channel 52 is located in an application section 50 of the housing 20 of the capsule 10. For instance by a movement of the piston 60 in the storage volume 32 along the longitudinal axis 46 towards the discharging end 38 of the storage vol ume 32, the compound 102 is forced in direction to the discharging end 38 and into the application channel 52. In the application channel 52 the compound 102 is guided to an application end 56 of the application channel 52 and a respective ap plication opening 24 of the housing 20 of the capsule 10. An application of the compound 102 can therefore be easily provided. Preferably, a cardinal volume orientation 80 of the storage volume 32 and a cardinal channel orientation 82 of the application channel 52 are arranged at an angle between 10° and 60° to allow an application of the compound 102 at regions otherwise not reachable.

Preferably, at least the housing 20 is composed of medical grade plastic material like PBT, PMMA, PA, COC and/or COP. For a sealing of the application end 56 and the application opening 52, respectively, an application sealing means 70 can be provided, for instance and as shown in Fig. 1 , a foil cover 72 or a plug 74. Pref erably, the foil cover 72 can comprise a multi-component foil. Especially, the appli cation sealing means 70 can be at least partly made of PBT and/or COP and/or COC.

According to the invention, the storage volume 32 of the capsule 10 comprises first sealing means 42 at an inner surface 40 of the storage volume 32, preferably at and/or near the filling end 36 of the storage volume 32. These first sealing means 42 can preferably be provided as protrusions 44. Further, the inner surface 40 of the storage volume 32, preferably the complete housing 20, and the first sealing means 42 are composed of the same material. By providing first sealing means 42 as part of the storage volume 32, a sealing of the storage volume 32 can be pro vided independently of the closing means 62 inserting into the filling end 36 of the storage volume 32.

The protrusions 44 are formed in one piece with the inner surface 40 and project from the inner surface 40 towards the longitudinal axis 46 and/or the cardinal vol ume orientation 80. Two protrusions 44 formed as sealing lips 44' are shown in Fig. 1 that extend circumferentially along the inner surface 40.

As shown in Fig. 1 , a piston 60 can be used as a closing means 62. Preferably, the piston 60 comprises second sealing means 64, for instance a circumferential sealing surface 66, to engage the first sealing means 42 and to therefore enhance the provided sealing. Additionally, the piston 60 can comprise a sealable venting hole 68 to allow air trapped within the storage volume 32 to escape. Also the pis ton 60 can be at least partly made of PBT, COP and/or COC.

In Fig. 2 an isometric view of a system 100 according to the invention with a first embodiment of a capsule 10 is shown. Within the housing 20 of the capsule 10, especially within the storage section 30, a storage volume 32 and additionally a compound 102 (both not shown) are located. At one end of the housing 20 of the capsule 10, an application section 50 is visible, wherein the application section 50 ends in an application opening 24 of the housing 20, whereby especially an appli cation end 56 of the application channel 52 is placed at the application opening 24.

Fig. 3 shows a system 100 according to the present invention with a second em bodiment of a capsule 10 in a sectional view. The system 100 at least comprises a capsule 10 according to the invention and, as shown in Fig. 3, preferably also a piston 60 according to the invention. The system 100, especially the capsule 10, is used to store and to applicate compounds 102, especially high viscosity com pounds 102, preferably compounds 102 for dental applications. These compounds 102 can be stored in a storage volume 32 of a storage section 30.

The storage section 30 is part of the housing 20 of the capsule 10. The compound 102 is stored in an essentially cylindrical middle section 34 of the storage volume 32. For a filing of the storage volume 32, a filling opening 22 in the housing 20 and respectively a filling end 36 of the storage volume 32 is used. The compound 102 is inserted into the storage volume 32 and can fill the storage volume 32 essential ly from is its filling end 36 up to its discharging end 38.

The discharging end 38 of the storage volume is connected to a storage end 54 of an application channel 52 of a capsule 10 in a fluid communication way. The ap plication channel 52 is located in an application section 50 of the housing 20 of the capsule 10. For instance by a movement of the piston 60 in the storage volume 32 along a cardinal volume orientation 80 towards the discharging end 38 of the stor age volume 32, the compound 102 is forced in direction to the discharging end 38 and into the application channel 52. In the application channel 52 the compound 102 is guided to an application end 56 of the application channel 52 and a respec tive application opening 24 of the housing 20 of the capsule 10. An application of the compound 102 can therefore be easily provided. Preferably, a cardinal volume orientation 80 of the storage volume 32 and a cardinal channel orientation 82 of the application channel 52 are arranged at an angle between 10° and 60° to allow an application of the compound 102 at regions otherwise not reachable.

According to the invention, the application section 50 of the housing 20 comprises a brush tip 58 at the application end 54 of the application channel 52. In other words, the brush tip 58 is a part, preferably an intrinsic part, of the housing 20 of the capsule 10. A planar application of the compound 102 can therefore be pro vided more easily. Preferably, a material of the brush tip 58 is softer than a materi al of the housing. For instance, the material of the brush tip 58 has a hardness measured with the Shore A Durometer selected in the range of 20A to 95A and up to a hardness measured with the Shore D Durometer of 55D, preferably in the range of 20A to 50A. By this, a planar application of the compound 102 stored in the storage volume 32 of the capsule 10 can be provided easily.

Especially, the housing 20 and the brush tip 58 can be produced in a 2-component injection molding process, a fast, easy and cost efficient production method. For an example, a brush tip 58 made up of a softer material can be combined with a housing 20 made up of a more rigid material. Additionally, a secure fixing of the brush tip 58 on the housing 20, for instance due to grooves and/or undercuts of the housing 20 filled with material of the brush 58 tip during the injection molding process, can easily be provided.

Preferably, in a first step of a method of producing a capsule 10 according to the invention, a mold is provided for the brush tip 58 and subsequently the brush tip 58 is injection molded using this brush tip mold. In other words, after the first step the brush tip 58 of the capsule 10 can already be provided.

In a second step of a method of producing a capsule 10 according to the invention, a mold is provided for the remnants of the capsule 10, wherein especially in this capsule mold the already molded brush tip 58 is inserted. Subsequently, the re maining parts of the capsule 10 are injection molded, wherein a material different of the brush tip 58 is used. During this second molding process, the material of the remnant of the capsule 10 preferably at least partly encloses the brush tip 58 and/or connects to the material of the brush tip 58 to provide a secure and/or re sistant interconnection of these two parts of the capsule 10 produced in a method according to the invention.

Preferably, at least the housing 20 and/or the brush tip 58 are composed of medi cal grade TPE and/or medical grade EVA. For a sealing of the application end 56, the application opening 52 and/or the brush tip 58, respectively, an application sealing means 70 can be provided, for instance and as shown in Fig. 3, a foil cov er 72 or a foil cover 64. Preferably, the foil cover 72 can comprise a multi- component foil. Especially, the application sealing means 70 can be at least partly made of PBT and/or COP and/or COC.

The brush tip 58 shown in Fig. 3 is composed of a plurality of bristles 58' that ex tend from the application end 54 of the application channel 52.

As shown in Fig. 3, a piston 60 can be used as a closing means to sealingly close the filling opening 22 of the housing 20. Preferably, the piston 60 itself comprises sealing means, for instance a circumferential sealing surface, to engage an inner surface of the storage volume 32 to provide the sealing. Also the piston 60 can be at least partly made of PBT, COP and/or COC.

In Fig. 4 an isometric view of a system 100 according to the invention is shown. Within the housing 20 of the capsule 10, especially within the storage section 30, a storage volume 32 and additionally a compound 102 (both not shown) are located. At one end of the housing 20 of the capsule 10, an application section 50 is visible, wherein a brush tip 58 is comprised at an application end 56 of an application channel 52. This brush tip 58 as part of the housing 20 of the capsule 10 accord ing to the invention allows a planar application of the compound 102 stored in the storage volume 32 in an especially easy and comfortable way.

Reference list

10 Capsule

20 housing

22 filling opening

24 application opening

30 storage section

32 storage volume

34 middle section

36 filling end

38 discharging end

40 inner surface

42 first sealing means

44 protrusion

44' sealing lip

46 axis

50 application section

52 application channel

54 storage end

56 application end

58 brush tip

58' bristle

60 piston

62 closing means

64 second sealing means 66 sealing surface 68 venting hole

70 application sealing means 72 foil cover

74 plug

80 volume orientation 82 channel orientation 100 System

102 compound