CLOSURE PACKAGE AND MANUFACTURING METHOD THEREOF
An improved valve (1) and countervalve (2) package and the manufacturing method thereof are disclosed. The package comprises at least one valve provided with a housing pocket and a countervalve, mutually coupled with respective peripheral surfaces with respect to said pocket, and along a substantial portion of the common perimeter edge of the valve (1) and of the countervalve (2) a sealing bead (3) is externally applied, obtained from an injectable plastic material through an injection mould
The present invention concerns an improved package, in particular a package with easy opening and improved recyclability.
BACKGROUND ARTAs known, in the field of small product packaging, containers which allow to exhibit the product to the consumer, in particular for sale, in addition to having a containment and protection function (in a more or less sealed manner), are very popular.
Packages of this type, informally referred to as “blister packs”, typically consist of two coupled elements, which are going to be called valves in the following: one makes up mainly a product-containing recess and the other a closing backing. One of the two elements, or even both, is preferably clear, so as to allow the user to see the package contents. The other element is normally in the shape of a plane sheet, namely a backing, which acts as carrier for all the required information (trademarks, instructions, statutory indications, and so on).
The clear valve may be made of a thin sheet of thermoforming plastic material, for example polyester, PVC or other. In certain cases, the plastic material valve may be obtained also through injection moulding. The countervalve, or backing, typically consists of paper, cardboard, or aluminum, but also of the same thermoplastic material the clear valve is made of. It is not necessarily flat, but can also be shaped with a pocket apt to house, at least partly, the objects to be contained. When the valve and countervalve are shaped with respective, containment pockets, a further planar element (backing) can be inserted between them which acts as partition element of the package volume (as in the example of
More in general, a number of other packages exist, which are not technically referred to as “blister packs” but which have a similar arrangement. Also, such packages generally consist of a valve—typically shaped in order to adapt to the product to be contained—and of a countervalve—which can be planar (as a closing lid) or variously shaped.
Typically, the coupling between the two valves (valve and countervalve) occurs along a planar perimeter area, immediately outside the thermoformed area which contains the product, through various techniques such as gluing, welding, ultra-sound welding and so on. Should the planar countervalve be made of cardboard or Other paper material, it is preferable to sprinkle the coupling surface thereof with a weldable varnish, so as to allow welding with the thermoformable plastic valve. In case of aesthetic packages, with metal effects, hologrammes or the like, the varnish or weldable paint may be replaced by a thin plastic film, coupled with the surface of the countervalve, suited to allow the welding to the valve.
In the packaging process, according to the known art, it is provided to thermoform the first valve from a continuous web of plastic material, obtaining the various containment pockets for the objects to be packaged. The thermoformed seats, or pockets, are then filled with the products to be packaged. Subsequently the thermoformed web is coupled with a second web which builds up the countervalve, or with a cardboard backing, performing then the mutual welding in the area at the periphery of the product pocket.
Finally, through a shearing system, the individual packages are separated from the continuous web: the packages are collected and packaged, while the off-cuts continue to a recycling station.
This production mode implies a number of problems, both from the point of view of package functionality, and from the point of view of the process.
Firstly, the known configuration of these packages, in particular of blister packs, makes the opening thereof very difficult. The coupling area between the two valves, in particular, has a sharp edge along which one finds it difficult to use one's fingers.
The strength of the welding and of the valve material hinders an easy opening of the package. Although cases exist in which this feature is even necessary, for example to discourage tampering, in the majority of cases this is perceived as an unpleasant disadvantage. As a matter of fact, the user does not appreciate having to make an excessive effort on the package in order to be able to release the product. Moreover, when acting forcefully to open the package, it is very easy to cause the ripping of the product therein contained (for example the slender neck or the small head of a toothbrush).
Even in the cases in which the countervalve or the backing is provided with pre cut lines (for example a series of distanced incisions), the opening generally requires a non-negligible effort. The pre-cut lines, moreover, impair the airtight sealing of the package and hence introduce an additional problem.
Another very relevant problem, also in the light of increasing attention towards the environment, is package recyclability. Since the materials making up the blister pack are often different, it is necessary to separate them effectively and easily. On the contrary, the coupling on the large perimeter area between the plastic valve and the cardboard backing—regardless of the fact that gluing or welding are used—often makes it impossible to suitably separate the different components.
From the point of view of the manufacturing process, the drawbacks are in short:
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- the cut-offs obtained during the manufacturing process consist of coupled products of different nature which, in order to be able to be used again, require costly post-finishing;
- shearing, to separate the individual packages from the continuous web, is performed with the thermoplastic valve coupled with the cardboard backing, which causes a premature wear of the shearing blades (cardboard is far more abrasive than plastic alone);
- welding/gluing occurs on a significant area of the web, which increases energy costs and material costs with respect to those strictly necessary for mutually welding the two valves;
- in order to obtain a quality welding it is often necessary to apply the thermowelding varnish, which represents an additional cost.
In order to partly solve these problems, it has been suggested to embed a tearing ribbon in the plastic valve material, so as to ease the stripping of said ribbon and hence the opening of the package. An example of this type is represented by DE102010032944. However, apart from the aesthetic impact which is not particularly pleasant, this solution implies the disadvantage of manufacturing complexity (while still using traditional welding techniques) and leaves the pull-off ribbon embedded in the valve material, which is not perfectly suitable for recycling the package once it has accomplished its purpose.
U.S. Pat. No. 3,835,224 discloses a closing system of a blister pack, wherein the welding step is avoided and the valve and countervalve are kept joined through a simple adhesive tape applied along the perimeter. This solution, as can be guessed, is difficult to be implemented on an industrial level. Moreover, since also an adhesive tape, in the light of the thinness thereof, would prove difficult to grasp to open the package, in this disclosure it is provided to remove or cut the tape along some peripheral edges, to expose the edge of the valve and countervalve and ease the opening: this is anti-aesthetic and impairs the airtight sealing of the package.
As a farther alternative, U.S. Pat. No. 3,217,867 proposes to keep valve and countervalve of a blister pack joined through a small peripheral frame. The peripheral frame is formed separately and then applied to the valve-and-countervalve assembly: this mode of mounting is complex and prevents from achieving package air tightness (due to the inevitable clearances existing between the two valves and the frame for mounting purposes). The mounting complexity, moreover, reflects into the general inconvenience of opening of the package, which requires the application of a significant effort to severe the frame. In order to withstand the deformation during mounting, without accidental ruptures, the frame carries constraints in the choice of materials and must have a significant section, which does not combine well with cost and appearance requirements.
SUMMARY OF THE INVENTIONThe object of the present invention is hence to provide a new type of package which overcomes all the above-cited drawbacks. It is furthermore intended to provide a package which has improved features, suited to impart also a certain originality and distinctiveness with respect to the traditional packages existing on the market.
Such object is achieved through a package and a manufacturing method as described in their essential features in the attached main claims.
Other inventive aspects of the package are described in the dependent claims.
In particular, according to a main aspect of the invention, it is supplied a package comprising at least one valve provided with a housing pocket and a countervalve, mutually coupled on surfaces of respective peripheral flanged portions, wherein, along a substantial part of a common perimeter edge of said flanged portions of valve and countervalve, a sealing bead of injectable plastic material is externally applied by moulding.
According to a preferred aspect, the bead of injectable plastic material has larger-extension areas alternated with smaller-extension areas. The larger extension areas have a width of about 1 to 5 mm, protruding outside said perimeter edge by about 0.5 to 1.2 mm. The smaller-extension areas have a width such as to cover the outer surface of the valve or countervalve at the most on a width of 1 mm. Preferably, the height or thickness of said bead is of about 0.2 to 2 mm on each side, in addition to the overall thickness of the flanged portions of the valve and countervalve and any other elements laid in between.
According to a further preferred aspect, the bead has at least one increased-thickness gripping element adjacent to a short bead area having reduced-thickness or preferential-ripping means.
Said injectable plastic material has adhesive properties but not intimate bonding properties with respect to the material of said valve and countervalve. Preferably, the injectable plastic material comprises an amount of 0-100% wt of rubber/elastomer and, more preferably, is TPE.
According to another aspect, the valve and countervalve have a perimetral flanged portion provided with retaining means, in the shape of holes and/or drawings and/or cavities, suited for cooperating in the retaining of said sealing bead.
According to a different aspect, a manufacturing method of a package is supplied, where the following steps are provided:
a valve having housing pocket is obtained from a continuous web of thermoformable material and subsequently filled with the object to be packaged,
a shearing and separation of the valve from the continuous web of thermoformable material is made to occur before the coupling with a countervalve already cut to measure,
said coupled valve and countervalve are then inserted into an injection mould and a bead of injectable plastic material is directly injection-moulded outside and along the common perimeter edge of said valve and countervalve.
According to a preferred aspect, the method provides to define deflection barriers for the injection flow of said injectable plastic material within said mould, between a point of injection into the mould and a groove meant to define the sealing bead, so as to divert the flow of injectable plastic material to a peripheral area, protecting the area downstream of said deflection barriers from pressure excesses in the flow of injected plastic material.
Further features and advantages of the package and of the method according to the invention will in any case be more evident from the following detailed description of some preferred embodiments of the same, given by way of example and illustrated in the attached drawings, wherein:
In the drawings and in the following description reference will be made to a blister pack for a toothbrush. It is understood that such representation is to be intended as a non-limiting example, since similar packages, according to the teaching of the invention, can be used also in other sectors.
As visible in
Valve 1 for example is in the shape of a thermoformable sheet of plastic material, suitably shaped for defining a main pocket 1a, for containing a toothbrush (or other object to be packaged), wherefrom a planar portion of flange 1b extends. While the pocket takes on the shape of the product it must contain, planar flange 1b preferably (but not necessarily) ends with a standard-shaped perimeter, for example rectangular or slightly shaped along a curved contour.
Countervalve 2 for example is a planar backing (for example a cardboard plate) having a contour equivalent to that of the flange portion 1b of main valve 1.
In any case, in a manner known per se, the countervalve can be made of the same material, as the valve, it can be planar or thermoformed into a pocket which contains a portion of the object to be packaged or other accessories (such as the head cover or bristle cover of a toothbrush and/or other promotional objects). In this latter case the package can consist of three elements: two valves and one backing, laid between (hence with a perimeter contour corresponding to that of the valve and countervalve) or inserted inside the coupling surface area of valve and countervalve.
The valves can also be made of materials differing from each other and be obtained by injection moulding.
Valve 1 and countervalve 2 are traditionally coupled so as to cause the inner surface of flange portion 1b to match the inner surface of planar countervalve 2 (or of a matching portion of planar flange thereof, should also the countervalve be provided with a pocket), bringing the respective perimeter edges in alignment.
In any case, for what is going to be stated in the following, it is important that both portions to be coupled (valve and countervalve) have along the perimeter at least one (even short) flange portion; according to another aspect, valve and countervalve should have perimeter flange portions which couple with each other on a same surface (whether planar or not).
According to the invention, along the perimeter edge of the valve/countervalve assembly (and possibly of a backing laid in-between) a sealing bead 3 of injectable plastic material is further provided by direct moulding. In particular, bead 3 is formed directly on the package by injection moulding, after having arranged the valve and countervalve assembly in a suitable injection mould.
Advantageously, as can be better seen in the following, the plastic material of sealing bead 3 is such as to have a low compatibility with the material of the valve and countervalve, that is, it tends to adhere tightly to the valve and countervalve surfaces, however, without gluing or bonding intimately. For such purpose, the plastic material of the bead is chosen so as to have a lower melting temperature than the plastic material valve 1 (and possibly countervalve 2) is made of.
For example, if valve 1 is made of polyester (for example polyethylenteraphtalate PET) and countervalve 2 is a backing of paper material, sealing bead 3 can be a polypropylene base (PP), preferably with a significant percentage of elastomeric material, or a thermoplastic elastomer (TEE).
As visible in the drawings, sealing bead 3 substantially covers the entire perimeter edge of the valve and countervalve assembly—at least on the entire length wherein the two edges are laterally exposed—being applied outside such elements.
This in case the two lateral edges of the valve and countervalve are substantially equivalent. In such case, to be able to obtain extension portions with accessory functions, it is possible to provide accessory elements integral with the same sealing bead. For example, as visible in the embodiment of
Inside the same fastening portion 2a or similar accessory extension portion of another suitable ramification, a distinctive element or a countermark (for example an RFID tact or a microchip) recognisable by automatic systems can furthermore be embedded.
As shown in
Such recesses 3′ are obtained by the provision of suitable means into the injection mould (not shown), for maintaining the valve perfectly and tightly coupled with the countervalve during the injection step of bead 3. As a matter of fact, the two perimeter flanges of the valve and countervalve are kept tightly pressed adhering one to the other, both to produce a sealing bead which then preserves the air tightness of the closing, and to prevent material of the bead 3 from penetrating inside the package, between the valve and the countervalve, during injection. For such purpose, the contour of the injection mould has a series of indents which—with a certain pitch, for example equal to 1-3 mm—keep the opposite, flanged inner surfaces, i.e. (in the embodiment of
This configuration is clearly evident also from observing
The bead can also have a differentiated width above and below the package.
In general terms, the overall width d of the bead can typically be of the order of 1-5 mm depending on the package type. The height or thickness of bead 3 is about 0.5-2 mm for each side, preferably 0.5-1.2 mm, in addition to the overall thickness of the flange portions of the valve and countervalve.
It is understood that the cross-section sizing of sealing bead 3 is such as to guarantee not only a structural resistance suitable for maintaining valve and countervalve joined after moulding, but also to advantageously maintain an integrity thereof during the tensioning action which is imparted during the tearing step as will be seen in the following). However, since the bead is moulded directly on the pack, it must not have an independent structural resistance, so that a vast choice of materials and resistances but also very small sections is available. In particular, in the embodiment of
The cross-section of the sealing bead can also be constant (as shown in
The dents provided, in the mould—with the purpose of keeping the flanged portions of valve and countervalve mutually tightened—can also be in the shape of pegs which then leave a respective imprint (crosswise hole) in the sealing bead.
In certain cases it is preferable for the bead to be as narrow as possible (to have a negligible aesthetic impact) and it is hence necessary to adopt devices to achieve all the same a good gripping with respect to the valve and countervalve despite renouncing the wavy or dented configuration. For such purpose, the flange portion of the valves are not smooth and compact, but possibly provided with small holes, recesses and/or suitable drawings, such as to define points of engagement with the moulded material and hence to be able to determine excellent mechanical cohesion between bead and valve.
To avoid seeping of the plastic sealing material of the bead between the two valves in the areas with highest injection pressure (i.e. in the proximity of the injection point), according to a preferred embodiment it is provided to arrange flow deflection barriers in the mould. In particular, a deflection barrier is arranged between the injection point in the mould and the groove intended to define the sealing bead: this barrier causes the flow of the injected molten material to be diverted towards a peripheral area, protecting the area “downstream” of the deflection barrier from pressure surges which would tend to cause seepage. The presence of such a barrier is made evident in the finished product by an area devoid of the material of sealing bead 3, for example as detailed in
Even more preferably, at least a portion of sealing bead 3 has easy-removal means 5. Since the sealing bead—as will be detailed in the following is meant to be removed, it is preferable for an increased-thickness portion to be provided, which aids grasping with one's fingers.
In the illustrated example (see
This represents a relevant aspect of the effectiveness of the invention. As a matter of fact, bead 3, due to the fact that it does not intimately weld with the valve and countervalve, but simply adheres during the moulding step, is meant to be torn off the valve and countervalve edge, without leaving any piece or residue joined thereto. The easy removal means 5 are meant to aid the opening of the bead, to then be able to tear it off the package. Evidently, in this step, it is appreciated that the bead be sufficiently tough to be ripped off in a single piece by simply pulling it from one end.
Once bead 3 has been torn and ripped, a full and perfect separation of the three materials (valve, countervalve and sealing bead) making up the package is obtained, with the option of differentiated disposal.
The manufacturing of such package can be performed through an injection moulding process, rather than using traditional welding/gluing techniques, with a series of advantageous operations.
A planar web of thermoforming material is made to progress, in a manner known per se, to form the product-containing pockets. Alternatively, a series of injection-moulded valves is created and conveyed along a transport line. Similarly to the prior art, the pockets are then filled with the corresponding products and possibly with internal cardboard plates/backing. After that the process provides to cut and separate the individual valves. The off-cuts which are recovered during this step are perfectly recyclable, not being coupled with any foreign material.
The valves containing the products to be packaged are conveyed and loaded on a lower half-mould for injection moulding (each mould could contain up to 6-12 valves simultaneously). Above the valves a corresponding number of countervalves (similarly obtained, for example) is arranged, for example using manipulators known per se in the field, causing the respective margins of the perimeter edges to match. The countervalves may be of any suitable material, comprising thermoforming plastic, cardboard, etc.
In a manner known per se, the half-mould loaded with valve and countervalve is sent to a moulding station.
In the injection position, the lower half-mould is coupled with a corresponding upper half-mould and hence the material making up the sealing head is pressure-injected.
Preferably, the two half-moulds are coupled, so that along the path where sealing bead 3 is to be injected a series of dents or opposite pegs are provided, as described above, which keep valve and countervalve tightly one against the other along the respective flange portions.
Alternatively, different configurations of the mould can be provided for best tightening valve and countervalve one against the other and to simultaneously define the groove or cavity for injecting the material to create the welding bead. Also the arrangement of mould and countermould can affect the effectiveness of the tightening. However, such aspects are not part of the present invention and will hence not be set forth in greater detail.
In the subsequent delivery station, after having removed, the upper half-mould, the complete packages are removed from the lower half-mould and are then cooled to the extent necessary for allowing a subsequent boxing thereof.
As can be guessed from the above-reported description, the proposed method and the package obtained according to the invention allow to perfectly achieve all the objectives set forth in the premises.
As a matter of fact, the package is obtained with the traditional valve and countervalve and a sealing bead which gives the package particular characterisation and distinctiveness.
The sealing bead ensures a perfect closing air tightness of the package, but at the same time is extremely easy to remove. The presence of gripping elements, easily definable in the bead moulding, although not necessary, can further aid package opening.
The easy removability of the bead from the package is advantageous both to aid the opening of the package even without having cutting tools—and to achieve excellent separation of all the components and hence a perfect management of the package for the purpose of differentiated disposal.
The simple opening by tearing of the sealing bead eliminates any risk connected with stresses and makes any resorting to pre-cut lines superfluous, to the advantage of package air tightness and of product integrity.
Despite the fact that the coupling and adhesion technique are innovative, the shape and size of the package do not differ substantially from the prior art, which allows to use handling tools and logistics exactly identical to those of the traditional case, making the packaging in already working industrial processes economic and acceptable.
From the point of view of the process, easily recyclable cut-offs are obtained as well as less wear of the shearing machines, which can act on the plastic material of the valves before any coupling with other wearing materials (such as backings). Moreover in the process the need to apply varnishes or paints or thermowelding films is fully removed and all the costs relating to welding equipment can be removed, as well as any uncertainty concerning the air tightness of the packages deriving from such prior-art processes.
However, it is understood that the invention is not limited to the particular embodiments described above, which represent only non-limiting examples of the scope of the invention, but that a number of variants are possible, all within the reach of a person skilled in the field, without departing from the scope of the invention as defined in the appended claims.
In particular, as indicated in the premises, the package according to the invention can be employed in a variety of application fields (for example classic food packages), also not strictly connected to the need for display (for example jars for food products), where its quality of making immediately evident any tampering attempts could also be exploited.
The presence of a valve and of a countervalve does not imply that these elements are fully separate in origin: as a matter of fact, they could be part of a same thermoformed sheet folded on itself along an edge.
Moreover, although the countervalve has been described mainly in the shape of a planar backing, as already mentioned the same invention teaching is applicable to a countervalve of plastic material, possibly itself provided with a pocket for the partial housing of the product no be packaged (as in the case of
Again, the combination between PP or PTE, as material of the sealing bead, with PET, as valve material, is to be intended as a non-limiting example, since a similar result can be achieved also with other combinations which ensure a good mechanical adhesion sealing of the bead on the edge of the valves and the incompatibility (i.e. the exclusion of a mutual, intimate bonding between the materials) between the material of the bead and that of the valves.
The materials used for the sealing bead and for the valves can be clear or opaque, neutral or coloured, classic or biodegradable.
Finally, it is not ruled out that the outer margin of the valve and countervalve, on the outer periphery of the injection position in the injection mould, is shaped so as to nevertheless define an inward barrier (suitably clamped during mould closure), but leaving a thin residual perimeter gap between the two opposite surfaces, into which part of the material, of the sealing bead could seep (during the injection moulding step). Such event, in addition to being tolerable, could prove advantageous for improving adhesion and the temporary sealing between valve and countervalve and for better retaining the sealing bead on the package.
Claims
1. A package comprising at least one valve provided with a housing pocket and a countervalve, mutually coupled on surfaces of respective peripheral flanged portions, wherein along a substantial part of a common perimeter edge of said flanged portions of valve (1) and countervalve (2), a sealing head (3) of injectable plastic material is externally applied by moulding.
2. The package as claimed in claim 1, wherein said bead of
- injectable plastic material has larger-extension areas alternated with smaller-extension areas.
3. The package as claimed in claim 2, wherein said larger-extension areas have a width (D) of about 1 to 5 mm, protruding outside said perimeter edge by about 0.5 to 1.2 mm.
4. The package as claimed in claim 2, wherein said smaller-extension areas have a width (d) such as to cover the outer surface of the valve or countervalve at the most on a width of 1 mm.
5. The package as claimed in claim 1, wherein the height or thickness of said bead (3) is of about 0.2 to 2 mm on each side, in addition to the overall thickness of the flanged portions of the valve and countervalve and any other elements laid in between.
6. The package as claimed in claim 1, wherein said bead (3) has at least one increased-thickness gripping element (5a, 5b) adjacent to a short bead area (3) having reduced-thickness or preferential-ripping means (5c).
7. The package as claimed in claim 1, wherein said injectable plastic material has adhesive properties but not intimate bonding properties with respect to the material of said valve and countervalve.
8. The package as claimed in claim 7, wherein said injectable plastic material comprises an amount of 0-100% wt of rubber/elastomer.
9. The package as claimed in claim 1, wherein said injectable plastic material is TPE.
10. The package as claimed in claim 1, wherein said injectable plastic material comprises a polypropylene-based (PP) material.
11. The package as claimed in claim 1, wherein at leas said valve or said countervalve are made of polyetylenteraphtalate (PET).
12. The package as claimed in claim 1, wherein at least said valve provided with pocket is made of thermoformable material.
13. The package as claimed in claim 1, wherein said countervalve is a planar cardboard backing.
14. The package as claimed in claim 1, wherein said valve and countervalve have a perimetral flanged portion provided with retaining means, in the shape of holes and/or drawings and/or cavities, suited for cooperating in the retaining of said sealing bead (3).
15. A packaging method of an object by means of a package
- as claimed in claim 1, wherein said valve (1) provided with housing pocket is obtained from a continuous web of thermoformable material and subsequently filled with the object to be packaged, wherein
- a shearing and separation of said valve (1) from the continuous web of thermoformable material is made to occur before the coupling with a countervalve (2) already cut to measure, wherein
- said coupled valve (1) and countervalve (2) are then inserted into an injection mould and a bead of injectable plastic material (3) is directly injection-moulded outside and along the common perimeter edge of said valve and countervalve.
16. The packaging method as claimed in claim 15, wherein deflection barriers of the injection flow of said injectable plastic material are defined in said mould, between a point of
- injection into the mould and a groove meant to define said sealing bead (3), so as to divert the flow of injectable plastic to said first product; registering tangible product on said computer; and responsive to registering the second product, enhancing said item in said computer activity.
Type: Application
Filed: Sep 6, 2012
Publication Date: Aug 21, 2014
Inventor: Eligio Ponzini (Milano)
Application Number: 14/343,945
International Classification: B65D 73/00 (20060101); B65B 51/02 (20060101); B65B 5/04 (20060101);