U.S. patent application number 14/343945 was filed with the patent office on 2014-08-21 for closure package and manufacturing method thereof.
The applicant listed for this patent is PONZINI S.p.A.. Invention is credited to Eligio Ponzini.
Application Number | 20140231295 14/343945 |
Document ID | / |
Family ID | 44898851 |
Filed Date | 2014-08-21 |
United States Patent
Application |
20140231295 |
Kind Code |
A1 |
Ponzini; Eligio |
August 21, 2014 |
CLOSURE PACKAGE AND MANUFACTURING METHOD THEREOF
Abstract
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
Inventors: |
Ponzini; Eligio; (Milano,
IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PONZINI S.p.A. |
Lazzate MB |
|
IT |
|
|
Family ID: |
44898851 |
Appl. No.: |
14/343945 |
Filed: |
September 6, 2012 |
PCT Filed: |
September 6, 2012 |
PCT NO: |
PCT/EP2012/067373 |
371 Date: |
April 9, 2014 |
Current U.S.
Class: |
206/462 ;
53/471 |
Current CPC
Class: |
B65B 51/02 20130101;
B65B 5/04 20130101; B65D 2575/365 20130101; B65D 75/366 20130101;
B65D 73/00 20130101 |
Class at
Publication: |
206/462 ;
53/471 |
International
Class: |
B65D 73/00 20060101
B65D073/00; B65B 51/02 20060101 B65B051/02; B65B 5/04 20060101
B65B005/04 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 8, 2011 |
IT |
MI2011A001615 |
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.
Description
FIELD OF THE INVENTION
[0001] The present invention concerns an improved package, in
particular a package with easy opening and improved
recyclability.
BACKGROUND ART
[0002] As 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.
[0003] 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).
[0004] 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 FIG. 6 here attached).
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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).
[0012] 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.
[0013] 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.
[0014] From the point of view of the manufacturing process, the
drawbacks are in short: [0015] 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; [0016] 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); [0017] 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; [0018] in order to obtain a
quality welding it is often necessary to apply the thermowelding
varnish, which represents an additional cost.
[0019] 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.
[0020] 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.
[0021] 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 INVENTION
[0022] The 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.
[0023] Such object is achieved through a package and a
manufacturing method as described in their essential features in
the attached main claims.
[0024] Other inventive aspects of the package are described in the
dependent claims.
[0025] 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.
[0026] 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.
[0027] 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.
[0028] 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.
[0029] 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.
[0030] According to a different aspect, a manufacturing method of a
package is supplied, where the following steps are provided:
[0031] a valve having housing pocket is obtained from a continuous
web of thermoformable material and subsequently filled with the
object to be packaged,
[0032] 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,
[0033] 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.
[0034] 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.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] 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:
[0036] FIG. 1 is a perspective view of a sample package according
to the invention;
[0037] FIG. 2A is a top plan view of FIG. 1;
[0038] FIG. 2B is a cross-section screw taken along line B-B of
FIG. 2A;
[0039] FIG. 2C is a cross-section view taken along line C-C of FIG.
2A;
[0040] FIG. 3 is an enlarged view of the detail enclosed in the
circle A of FIG. 2B;
[0041] FIG. 4 is an enlarged view of the detail enclosed in the
circle B of FIG. 2C;
[0042] FIG. 5 is a perspective view of the sole closing bead
according to the embodiment of FIG. 2A;
[0043] FIG. 5A is an enlarged view of the detail enclosed in the
circle C of FIG. 5; and
[0044] FIG. 6 is an exploded, perspective view of another
embodiment of the invention.
DETAILED DESCRIPTION OF CURRENTLY PREFERRED EMBODIMENTS
[0045] 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.
[0046] As visible in FIG. 1, a blister pack consists, in a manner
known per se, of a containing valve 1 and of a countervalve 2 which
can be mutually coupled along a common plane.
[0047] 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.
[0048] 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.
[0049] 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.
[0050] The valves can also be made of materials differing from each
other and be obtained by injection moulding.
[0051] 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.
[0052] 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).
[0053] 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.
[0054] 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.
[0055] 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).
[0056] 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.
[0057] 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 FIG. 2A,
the accessory element can be a fastening portion 2a, suited to
suspend the package from a display unit in a sales point. It is
integrally obtained with the sealing bead 3, possibly directly in
the mould during the injection moulding process. Similar accessory
portions can take on different shapes, possibly for marketing
purposes (for example a small animal product aimed at
children).
[0058] 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.
[0059] As shown in FIGS. 1-5, according to a preferred embodiment
of the invention, the injected sealing bead 3 has smaller-width
portions alternated with larger-width portions. Seen differently,
the constant width d of the bead (partly overlapping valve and
countervalve surface, partly protruding beyond the outer edge) is
interrupted by a series of recesses or notches 3' which, ending in
the proximity of the outer edge of flange 1b, locally reduce the
width of bead 3 substantially.
[0060] 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 FIGS.
3-4) the inner surfaces of flanged portion 1b (flange) and backing
2 (counterflange) tightly coupled to an extent coming close to the
perimeter edge. Between one mould dent and the other, small free
areas remain defined which allow the continuous injection of
sealing bead 3, which thus grips for a certain depth (in the width
direction of the valves) above and below the valve and the
countervalve, respectively, in addition to covering the entire
sharp edge of the peripheral edges.
[0061] This configuration is clearly evident also from observing
FIGS. 3 and 4 which show an exemplifying bead in cross-section. The
bead is moulded along the package perimeter so as to protrude
externally beyond the margin of the perimeter edge, so as to define
a sufficiently wide section as to keep the bead tightly secured to
the perimeter edge. In the example shown, such width by which the
bead protrudes is 0.9 mm; the overall width of the bead (FIG. 4) in
the widest areas is 3 mm (of which, hence, 2.1 mm overlapping valve
and countervalve), while in correspondence of recesses 3 (FIG. 3)
such width reduces to 1.5 mm (of which only 0.6 mm overlapping
valve and countervalve).
[0062] The bead can also have a differentiated width above and
below the package. FIG. 4 shows for example that width d is 3 mm in
contact with valve 1b, while it is 2.5 mm in contact with
backing-type countervalve 2. The width of the bead depends also on
the adhesion capability of the bead material with respect to the
material of the valve and countervalve.
[0063] 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.
[0064] 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 FIG. 6, wherein sealing bead 30
has no accessory function, a than profile of soft TPE can be used,
which is perfectly suited to the purpose, although extremely simple
to be removed subsequently.
[0065] The cross-section of the sealing bead can also be constant
(as shown in FIG. 6) and/or of any geometric shape suited to meet
the aesthetic requirements and/or suited to meet the suitable
structural resistance requirements of the pack.
[0066] 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.
[0067] 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.
[0068] 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 FIG. 2A with slit 4 between extended portion 2a and
bead 3.
[0069] 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.
[0070] In the illustrated example (see FIGS. 5 and 5A), on the
shorter side of the rectangular perimeter, bead 3 has a pair of
opposite, increased-thickness protrusions 5a and 5b, integral with
bead 3 (the protrusions preferably project from both sides of the
package, as can be noticed also in FIG. 1). Between the two
protrusions 5a and 5b a short portion 5c having reduced-thickness
or preferential-tearing means 5c is provided. The tearing action
which can be performed on the two protrusions 5a and 5b by the
fingers of a hand allows to easily rip the reduced-thickness area
5c and to hence open sealing bead 3 in a specific point.
[0071] 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.
[0072] 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.
[0073] 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.
[0074] 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.
[0075] 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.
[0076] In a manner known per se, the half-mould loaded with valve
and countervalve is sent to a moulding station.
[0077] 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.
[0078] 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.
[0079] 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.
[0080] 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.
[0081] 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.
[0082] 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.
[0083] 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.
[0084] 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.
[0085] 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.
[0086] 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.
[0087] 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.
[0088] 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.
[0089] 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.
[0090] 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 FIG.
6).
[0091] 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.
[0092] The materials used for the sealing bead and for the valves
can be clear or opaque, neutral or coloured, classic or
biodegradable.
[0093] 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.
* * * * *