Valve for a packaging container

Abstract

A valve for a packaging container is proposed, wherein the valve comprises at least one base film (10) with an opening (11), at least one frame film (13) encompassing a free region (17), and at least one membrane (12) which is arranged on the base film (10) and covers the opening (11), wherein a fluid is provided between the membrane (12) and the base film (10), wherein the membrane (12) is connected to a surrounding film (20) via at least one connection region (22), the surrounding film (20) being connected on one side to the base film (10) and on its other side to the frame film (13) and the membrane (12) being arranged movably within the free region (17), wherein the surrounding film (20) is open at least in one point, such that a channel (18) is formed.

Claims

1. A valve for a packaging container, comprising at least one base film (10) with an opening (11), at least one frame film (13) encompassing a free region (17), and at least one membrane (12) which is arranged on the base film (10) and covers the opening (11), wherein a fluid is provided between the membrane (12) and the base film (10), wherein the membrane (12) is connected to a surrounding film (20) via at least one connection region (22), the surrounding film (20) being connected on one side to the base film (10) and on its other side to the frame film (13), wherein the membrane (12) is arranged movably within the free region (17), wherein the surrounding film (20) includes an outer perimeter, and wherein the outer perimeter of the surrounding film (20) is open at least in one point such that a channel (18) is formed in the surrounding film (20).

2. The valve according to claim 1, wherein the connection region (22) is arranged opposite the channel (18).

3. The valve according to claim 1, wherein the surrounding film (20) encompasses the membrane (12) at least partially in a circular shape or in a U shape.

4. The valve according to claim 1, wherein the membrane (12) is implemented in a circular shape.

5. The valve according to claim 1, wherein the base film (10), the frame film (13) and the membrane (12) are equally usable and/or arrangeable within a packaging container or outside a packaging container.

6. The valve according to claim 1, wherein a thickness of the frame film (13) is greater than a thickness of the membrane (12).

7. The valve according to claim 6, wherein the thickness of the frame film (13) is greater than the thickness of the membrane by 75% to 225%.

8. The valve according to claim 1, wherein at least one cover film (15) is provided, which is connected to the frame film (13).

9. The valve according to claim 8, wherein the base film (10) and/or the frame film (13) and/or the cover film (15) are/is implemented of polypropylene, PP-EVOH-PP, OPP, PET, polyolefin or of a synthetic material.

10. The valve according to claim 9, wherein the base film (10) and/or the frame film (13) and/or the cover film (15) are/is made of sustainable raw materials or of bio-degradable synthetic materials.

11. The valve according to claim 8, wherein the frame film (13) is connected to the base film (10) and/or to the cover film (15) via a welding connection.

12. The valve according to claim 11, wherein the frame film (13), the base film (10), and/or the cover film (15) are laminated together.

13. The valve according to claim 1, wherein the frame film (13) includes an outer perimeter, and wherein the outer perimeter of the frame film (13) is open at least in one point such that a channel (18) is formed in the frame film (13).

14. The valve according to claim 13, wherein the channel (18) formed in the frame film (13) and the channel (18) formed in the surrounding film (20) connect to form a passageway connecting the opening (11) to an ambient region surrounding the valve (8).

15. The valve according to claim 14, wherein at least one cover film (15) is connected to the frame film (13), and wherein the channel (18) formed in the frame film (13) and the channel (18) formed in the surrounding film (20) are located between the base film (10) and the at least one cover film (15).

16. The valve according to claim 1, wherein the channel (18), viewed in a main extension plane of the surrounding film (20), forms a material-free interruption in the outer perimeter of the surrounding film (20).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Implementations of the invention will be described in detail with reference to the included figures. It is shown in:

(2) FIG. 1 an exemplary embodiment of an outside-situated valve, in which the membrane is partly connected to the surrounding film,

(3) FIG. 2 a production method for the valve of FIG. 1, in which individual film webs are punched and welded, and

(4) FIG. 3 an exemplary embodiment of an inside-situated valve, in which the membrane is partly connected to the surrounding film.

DETAILED DESCRIPTION

(5) In the following the exemplary embodiments of the invention will be described in detail with reference to the figures.

(6) FIG. 1 shows an exemplary embodiment of the valve 8. The valve 8 comprises a base film 10 with at least one opening 11. The opening 11 has, for example, the geometry of two intersecting and/or overlapping circles. The membrane 12 is connected to a surrounding film 20 via at least one, in particular narrow, connection region 22. However, the major portion of the membrane 12 is still freely movable. The membrane 12, the connection region 22 and the surrounding film 20 are thus implemented by a single part. The surrounding film 20 encompasses the membrane 12 except for a small channel 18. The at least one connection region 22 between the surrounding film 20 and the membrane 12 is realized on a middle of a side of the surrounding film 20. The membrane 12 and the surrounding film 20 are implemented of the same film, respectively are embodied in a one-part implementation. The thickness of the surrounding film 20 hence corresponds to the thickness of the membrane 12. In the exemplary embodiment the surrounding film 20 is on one side open in a relative narrow manner with respect to the total width. This enables the forming of the channel 18.

(7) A large portion of the membrane 12 is capable of lifting free off the opening 11, respectively off the base film 10. This is ensured by a free region 17 formed by the frame film 13 that is situated above the base film 10. The free region 17 is implemented so as to allow the membrane 12 securely lifting off upwards into said free region 17. For this purpose, the free region 17 of the frame film 13 is realized somewhat larger than the membrane 12 and is arranged above the membrane 12. The contour of the surrounding film 20 is at least partly aligned with the frame film 13. The surrounding film 20 is connected with the frame film 13.

(8) The connection of the base film 10 to the frame film 13 and/or of the frame film 13 to the cover film 15 is preferably realized via a welding procedure. The films 10, 13, 15 are implemented so as to be weldable. The films 10, 13, 15 are preferentially implemented of a synthetic material. Particularly preferentially the valve 8 is implemented of films with the same material. Here polypropylene is especially suitable. Due to the uniform material of the different films 10, 13, 15, re-usability is simplified. Synthetic materials based on sustainable raw materials or bio-degradable synthetic materials may also be utilized. The base film 10 and/or the frame film 13 and/or the cover film 15 may, for example, be implemented of polypropylene, preferentially of OPP (oriented polypropylene), i. e. a propylene that is stretched longitudinally or biaxially. The base film 10 and/or the frame film 13 and/or the cover film may alternatively be implemented of PET or of a composite film, like for example PP-EVOH-PP. The material of the membrane 12 is distinguished by a high oxygen barrier. For example, the membrane 12 is made of PET or of a composite material like PP-EVOH-PP.

(9) The alternative exemplary embodiment of FIG. 3, which is also covered by the idea of the invention, is realized as an inside-situated valve 8. With respect to the exemplary embodiment of FIG. 1, on the one hand there is neither a cover film 15 nor a channel 18. The other side of the opening 11 is covered by a filter 16, in particular a nonwoven filter 16. The filter 16, respectively the nonwoven, is necessary so as to prevent particles of the filling material from entering into the valve 8 between the membrane 12 and the base film 10, which would affect functionality. However, the membrane 12 is in particular, in its turn, connected to the surrounding film 20 via the connection region 22, as a result of which this is a one-part implementation.

(10) The following geometries may be particularly suitable for the valve 8. In the exemplary embodiments of FIG. 1, respectively 3, the edge lengths of the base film 10 may be in the range between preferentially 12.5 mm and 20 mm. The thickness of the base film 10 is preferentially in the range between 0.1 mm and 0.25 mm, and is particularly preferentially for example 0.125 mm. The fluid, for example silicone oil or fluids based on bio-based materials and/or sustainable raw materials, e. g. based on palm oil, coconut oil or the like, is applied as a fluid film. The volume of the fluid film is approximately 2 ?l to 5 ?l. The thickness of the membrane 12 is, for example, in a range between 0.025 mm and 0.075 mm, and is preferentially 0.05 mm. The thickness of the frame film 13 is, for example, in the range between 0.1 mm and 0.2 mm. The thickness of the frame film 13 is greater than the thickness of the membrane 12. The thickness of an optional cover film 15 is, for example, in the range of 0.05 mm to 0.15 mm, particularly preferentially 0.1 mm. Depending on an application case, material selection, connection methods etc., thicknesses may vary accordingly.

(11) For the production of the membrane 12, for example, a film corresponding to the base area of the base film 10 is punched out so as to provide the circle-shaped contour of the membrane 12. It is advantageous for the production process if the membrane 12 is connected to the surrounding film 20 in at least one point or in several points (respectively by one or several small webs), respectively connection regions 22. The production and positioning of the membrane 12 can thus be simplified. The region 22, respectively regions 22, in which the membrane 12 is still connected to the surrounding film 20, is/are small relative to the circumferential direction of the membrane 12, such that a lifting of the membrane 12 in the free regions is ensured.

(12) It is however also possible that a plurality of connection regions 22 are provided. These connection regions 22 are to be arranged in such a way that a lifting of the membrane 12 off the opening 11 is still reliably possible.

(13) The production process according to FIG. 2 serves for the production of a valve 8 according to FIG. 1. It is distinguished in that in each case separate film webs are fed in for the base film 10, for the surrounding film 20 with the attached membrane 12, for the frame film 13 and/or if applicable for the cover film 15. The individual film strips of the above-mentioned films 10, 13, 15, 20 usually have identical widths.

(14) First of all, the base film 10 is provided. The base film 10 may already have openings 11. Alternatively, the openings 11 may be created, e. g. punched, in situ. The punching is however to be executed before the lamination process.

(15) In a further step, a fluid, respectively a fluid film, is applied onto the base film 10, this is done in the places where later on the membrane 12 will come to rest, in particular in the region surrounding the opening 11. Alternatively, the fluid film could already be applied on the underside of the membrane 12. Alternatively, the fluid could be applied later on, for example in the applicator which connects the valve to the packaging material.

(16) In a further step, the surrounding film 20, with the membrane 12 connected via the connection region 22, is applied onto the base film 10. For the production of the surrounding film 20, with the membrane 12 connected via the connection region 22, and/or with at least one channel 18, a corresponding punching process may create the contours of the membrane 12 and/or may punch out what will be the channel zone 18 later on. By the punching process, the membrane 12 is separated from the surrounding film in such a way that the two are connected to each other only via the at least one connection region 22. The surrounding film 20, with the membrane 12 connected via the connection region 22, is fixedly connected to the base film 10. Preferentially the connection may be generated, as has been described, via a suitable welding connection. For example, hot-air welding, thermal-contact welding, induction welding, cold welding and ultrasonic welding (possibly others as well) may be considered as welding methods. However, alternatively other connection methods like gluing etc. are possible.

(17) Then the frame film 13 is applied onto the surrounding film 20. Herein the free region 17 comes to rest above the membrane 12. This enables a lifting of the membrane 12 into the free region 17. The free region 17 has previously been punched out of the frame film 13. The applied frame film 13 is connected to the surrounding film 20. This may preferably be realizedas described abovevia a corresponding welding connection. However, alternatively further connection methods are feasible, like gluing. It is essential that only the surrounding film 20 is connected to the frame film 13 but not the membrane 12. The freedom of movement of the membrane 12, which is movably held only by at least one connection region 22, is thus ensured.

(18) After this the cover film 15 may be applied onto the frame film 13. Then the cover film 15 is connected to the frame film 13. This may preferably be realizedas described abovevia a corresponding welding connection. However, alternatively further connection methods are feasible, like gluing. This step could be dispensed with, for example for inside-situated valves 8 which do not require a cover film 15.

(19) The singulation of the valves 8, which are arranged contiguously on a film web, may be realized in the packaging machine, in particular via the afore-described applicator. Alternatively, the singulation could also be realized directly following the joining of the films 10, 13, 15, 20.

(20) The described valves 8 are used, for example, as aroma-protection valves of packagings of outgassing products, like for example coffee beans, ground coffee, fresh dough or the like, in which after a packaging process an overpressure is produced within the packaging that is caused by outgassing filling materials. Pressure relief is brought about by a lifting of the membrane 12 relative to the opening 11, respectively to the base film 10, the pressure then escaping via the free region 17, respectivelyin the case of an outside-situated valvevia at least one sidewise channel 18, which is in a connection with the free region 17 and is implemented between the frame film 13 and the cover film 15.