EP2978676A1

EP2978676A1 - Container cap having tamper-proof means, container with said cap and method for manufacturing said cap

Info

Publication number: EP2978676A1
Application number: EP13714596.7A
Authority: EP
Inventors: Isabelle Fandeux; Vincent Loisel; Michel Roussy
Original assignee: Societe des Eaux Minerales dEvian SA SAEME
Current assignee: Societe des Eaux Minerales dEvian SA SAEME
Priority date: 2013-03-26
Filing date: 2013-03-26
Publication date: 2016-02-03
Also published as: MX2015013426A; AR095748A1; WO2014154255A1; BR112015024753A2; CN105228914A

Abstract

The invention pertains to an improved container (e.g bottle) cap (1) which is a single use leakproof closing, which shows obvious indications of an illicit opening and re-use, having tamperproof means which make easier the opening of the cap and which enables non- waterproof re-closings after a first opening. This cap (1) is molded from at least two different thermoplastic material TPM1 and TPM2, this latter being more tearable than TPM1, and comprises: • - a top wall (3), • - an annular skirt (4) extending downward from the top wall (3) and having a bottom edge (10), • - means (5) for fixing the cap (1) on the neck finish (100) of the container, • - at least one pull and tamper-proof tear tab (6) which is at least a part of the skirt (4), and which comprises two tear lines (8,9) extending between the bottom edge (10) of the skirt (4) and the top of the skirt (4); the tear lines being made ofTPM2.

Description

CONTAINER CAP HAVING TAMPER-PROOF MEANS, CONTAINER WITH SAID

CAP AND

METHOD FOR MANUFACTURING SAID CAP Field of the invention

The invention relates to a cap for closing the neck finish of a container -preferably a bottle- suitable for containing water or other liquids for human consumption (generically drinking water hereafter). More particularly, said container is of the type of those which are used in water dispensing units.

The container closed with said cap as well as the method for manufacturing said cap, are encompassed in the present invention.

Background

Containers, especially bottles, also named jugs, which are employed in the servicing of drinking water dispensing units are prone to infringement through the filling offence. This latter consists in filling empty containers bearing an authentic registered trademark, with a liquid (e.g. drinkable water) which is not the authentic liquid. Such a criminal act is not only deleterious for the brand image of the owner of the trademark, but represents also a major health risk, in view of the doubtful quality of the infringing liquid.

To fight against that some tamper-proof containers for drinking water have been developed.

A known cap of this type is especially disclosed in WO2010131 100A1 concerning a container lid of multicolor injection, which is designed in such specific shape that it can be attached and opened easily, and will not leak when used, and which prevents the removing of the lid of a bottle or a container without breaking the first opening indicating means in order to replace on a used container which have been refilled. Said container lid comprises two parts, an circular upper lid and a lower lid linked each other by a connecting part. The connecting part together with a puller grip which is hollow at its center with the shape of water droplet, are joined with the middle part of lower body of the container lid. The upper lid has an external layer of a first material which is Low Density Polyethylene (LDPE) colored in white and an inner layer of High Density Polyethylene (HDPE) colored in blue. The connecting part has a thicker inner layer made of the second material (HDPE) and an external layer made of the second material (LDPE). Said connecting part is linked to the upper lid by a thin upper web (HDPE with portions in LDPE) and to the lower lid by a thin lower web (HDPE). This container lid can be used only for a single usage because the connecting part has been broken, however it is still possible to use it furthermore even when the connecting part has been broken because the upper lid (1) may also be retained to the edge of the bottle hole, but the safety is not guaranteed anymore because the connecting part has been broken, so users, of course, know that the lid has been opened. The use of two colors and of a multi- injection process improve the anti-counterfeiting effect of the lid. First the users seem to detect more readily a defect in a two color lid. Secondly, attempts to weld or to glue a two colors plastic device tend to creates burrs and flashes easily viewable by the users. The container lid according to WO2010/131100 is perfectible in terms of tamper-proofing, of easiness to open and of manufacturing.

WO03002421A1 discloses a LDPE bottle cap including an improved sealing bead configured to engage a container crown proximal the maximum diameter thereof, and an improved tear tab extending between two lines of weakness, along a skirt upward from a bottom edge of the bottle cap and onto a top of the bottle cap.

Objectives of the invention

In the above recalled background, the invention aims at fulfilling at least one of the following objectives:

1. Providing an improved container (e.g bottle) cap which is a single use leak-proof closing.

2. Providing an improved plastic injection molded container (e.g bottle) cap which complicates a lot the counterfeiting consisting in removing the cap, filling the container with a non-authentic liquid and put back sealingly the cap with no apparent signs of previous removal.

3. Providing an improved tamperproof cap which fulfils at least one of the objectives 1 and 2, and which shows obvious indications of an illicit opening and re -use.

4. Providing an improved tamperproof cap which fulfils at least one of the objectives 1 to 3 and having tamperproof means which make easier the opening of the cap.

5. Providing an improved tamperproof cap which fulfils at least one of the objectives 1 to 4 and having tamperproof means which enables non-waterproof re-closings after a first opening.

6. Providing an improved tamperproof cap which fulfils at least one of the objectives 1 to 5, which makes it possible to render the appearance of the cap more attractive.

7. Providing an improved tamperproof cap which fulfils at least one of the objectives 1 to 6, which is economical and simple to manufacture by means of a multi-injection process.

8. Providing a container -e.g. a bottle- closed by a cap as defined in at least one of the objectives 1 to 5. Summary of the Invention

The invention aims at solving the above mentioned problems.

To this end, according to a first aspect, the invention provides a cap Cap for closing the neck finish of a container -preferably a bottle-, said cap being molded from at least two different thermoplastic material TPM 1 and TPM2 , this latter being more tearable than TPM 1 , said cap comprising:

a top wall,

an annular skirt extending downward from the top wall and having a bottom edge,

reversible opening / closing means of the cap on the neck finish of the container, said means being preferably screw thread means located inside the cap, and more preferably on the inner face of the skirt;

means for fixing the cap on the neck finish of the container, said means being preferably located inside the cap, and more preferably on the inner face of the skirt,

at least one tear tab:

^■ which is at least a part of the skirt,

^■ which comprises at least one, preferably at least two tear lines, ■ and which is a pull and tamper-proof means

wherein

the tear lines extend between the bottom edge of the skirt and at least the top of the skirt;

at least the tear lines and/or at least the tear tab are made of TPM .

This peculiar structure increases the efficiency of the tamperproof means in terms of easiness of tearing and of prevention of re-use for infringement.

According to a preferred embodiment, the tear lines extend between the bottom edge of the skirt and at least the top wall, on which the tear lines preferably continue inward.

In a first variant of the cap according to this preferred embodiment, the tear tab is made of TPM and the tear lines converge inward on the top wall and join themselves. In this variant, at least a part of the rest of the cap is made of TPM¹.

Such a cap can be obtained by a multi-injection process, for instance a bi-injection process when the entire tear tab, including the tear lines, is made of TPM whereas the rest of the cap is made of TPM¹.

The tear tab can be partially torn or totally torn and removed. In a second variant of the cap according to this preferred embodiment, the tear tab is

1 2

made of TPM and the tear lines of TPM . There are so two tear lines converging inward on the top wall, the ends of said tear lines not joining themselves so as to leave a passageway for the TPM¹, intended to form the tear tab during molding. Thus, TPM¹ preferably forms the whole of the cap, with the exception of the tear lines.

Advantageously, at least one of said tear lines, preferably the two tear lines extending on the skirt, is (are) substantially parallel to the axis of the cap or substantially perpendicular to the top wall.

It is a peculiarity of the invention that TPM 1 and TPM 2 are weldable between

1 2 them, the difference between the respective melting temperatures of TPM and TPM , being preferably less than 20°C; more preferably less than 10°C. It is a condition for the implementation of a multi(bi)injection process for the manufacture of said cap.

2 1

TPM "more tearable" than TPM means for instance and notably that the density of TPM 2 is less than or equal to 930 kg/m 3 and/or its tensile strength at yield is less than or equal to 20 or 15 MPa and/or its Elongation Break-EB- (ISO 527-1976 type 2 vitesse D) is less than or equal to 500 %.

According to a noteworthy feature of the invention, the difference between the EB of TPM¹ and the EB of TPM is greater or equal to -in % and in an increasing order of preference- : 50 ; 60 ; 70 ; 80 ; 100 ; 500 and preferably comprised between 80 and 1000.

TPM¹ is preferably a polyolefm and more preferably a High Density Poly Ethylene (HDPE) or a Linear Low Density PolyEthylene (LLDPE), and mixtures and/or alloys thereof.

TPM is preferably a polyolefm and preferably a Low Density PolyEthylene (LDPE) or a Linear Low Density PolyEthylene (LLDPE), and mixtures and/or alloys thereof.

According to an interesting feature of the invention, at least one tear line (preferably all tear lines) is made of a web continuous or not (bridges), the thickness (t^w) of which is defined as follows with respect to the minimum thickness of the skirt (t^mc), in an increasing order of preference:

tw < _tmc . _tw _≤ o.₉₅(t^mc) ; _t ^w < 0.90(t^mc) ; t^w < 0.85(t^mc) ;

0.3(t^mc) < t^w < 0.8(t^mc).

According to a possibility, the skirt is substantially circular and the tear tab has a sector comprised -in ° and in an increasing order of preference- between 10 and 90 ; 20 and 80 ; 30 and 70 ; 40 and 60. In view of improving the appearance of the cap:

the colour of the tear tab and/or the colour of the tear lines is(are) preferably different from the colour of the rest of the cap, and/or,

the cap comprises at least one pattern, preferably at least one graphic pattern, said pattern(s) being preferably placed at least on the top wall, and preferably made of

TPM² .

Advantageously, the retaining means include non reversible retaining means and, preferably, reversible retaining means. For instance, these latter can be screw means; whereas the non reversible retaining means are elements of complementary form respectively arranged on the inner face of the skirt and on the external face of the container's neck finish, said elements being preferably ribs and grooves, more preferably (dis)continuous bead(s) on the inner face of the skirt capable to be fitted into a complementary groove of the container;

and wherein the non reversible retaining means arranged on the inner face of the skirt are designed so as to leave a way for the tear line(s).

The removal of the tear tab makes it possible the desactivation or the unlocking of the retaining means.

In this aim, the cap is preferably designed so, as soon as the tear-tab is torn to at least 50% of the length of the tear line(s), the retaining means are deactivated, enabling so the removal of the cap from the container, said removed torn cap remaining a non liquid-proof closing for said container.

Outstandingly, the cap according to the invention can further comprise a plurality of ribs extending parallel to the central axis on the outer surface of the skirt.

According to a second aspect, the invention concerns a container -preferably a bottle- closed by a cap as above defined. Said container sealed with the cap, is preferably filled with a liquid, preferably a beverage, for example water, still or sparkling energy drinks or carbonated drinks such as sodas or colas.

In a more particular embodiment, the container is a jug, notably for liquids (especially drinking water), used in beverages dispensing units (e.g. Home & Office Delivery HOD).

According to a third aspect, the invention concerns a method for manufacturing a cap according as defined above, said method comprising the steps of:

- molding, in a cavity of a mold, the part(s) of the cap in TPM¹,

- overmolding, in the cavity of the mold, the part(s) of the cap in TPM , preferably at least one tear tab and/or at least one tear line. Definition

According to the terminology of this text, the following non limitative definitions have to be taken into consideration:

Every singular designates a plural and reciprocally.

"bottle" refers to any container for liquids, especially beverages like water: bottles, jugs, fountains, barrels, in particular adapted for beverage dispensers (Home & Office Delivery HOD), the capacity of which being, for instance, between 10 liters and 21 liters.

"thermoplastic" refers to mouldable thermoplastic homopolymer or copolymer that becomes pliable or moldable above a specific temperature, and returns to a solid state upon cooling.

"moulded" refers to any forming technique of thermoplastic raw materials, such as extrusion blow moulding, extrusion profiles & sheet, injection blow moulding, injection moulding injection moulding (gas assisted), injection stretch blow moulding insert moulding, rotational moulding, compression moulding.

Detailed description of the invention

Other objects and advantages of the invention will emerge from the following disclosure of particular embodiments of the invention given as non limitative examples, the disclosure being made in reference to the enclosed drawings in which:

- Figure 1 is a perspective view of a cap according to a first embodiment of the invention, wherein the tear tab is not torn;

- Figure 2 is a perspective view of a cap of Figure 1 screwed on a neck finish, wherein the tear tab is partially torn;

- Figure 3 is a top view of Figure 1,

- Figure 4 is a section view in the diametral plane according to the line III-III of the cap of Figure 1,

- Figure 5 is a bottom view in perspective of a cap according to Figure 1;

- Figure 6 is a perspective view of a cap according to a second embodiment of the invention, wherein the tear tab is not torn;

- Figure 7 is a perspective view of a cap of Figure 6 screwed on a neck finish, wherein the tear tab is partially torn;

- Figure 8 is a top view of Figure 6,

- Figure 9 is a section view in the diametral plane according to the line IX-IX of the cap of Figure 6,

- Figure 10 is a bottom view in perspective of a cap according to Figure 6;

- Figure 11 is a section view in a diametral plane of the cap of Figure 1 , screwed on the neck finish of a bottle. On the Figures, the same reference numbers refer to the same or similar elements.

Figure 1 represents a first embodiment of a cap 1 for closing the opening of a container, such as a plastic bottle, adapted to receive a product, and especially a liquid product such as water, optionally flavoured and/or carbonated, a soda, a fruit juice, a milk based liquid product or other.

The container shown on Figures 2, 7, 11 comprises a neck finish 100 delimiting the opening for pouring the product.

In the illustrated first embodiment (Figures 1-5), the cap 1 presents a symmetry of revolution about a central axis A and comprises a molded shell 2 which is substantially annular and which is composed of:

a top wall 3,

a skirt 4,

reversible opening/closing means 5 of the cap 1 on the neck finish 100 of the container, said means 5 being screw thread means located inside the cap 1, on the inner face 15 of the skirt 4,

and a tear tab 6 including a part of the top wall 3, a part of the skirt 4 and a downward projecting appendix 7. The tear tab

The tear tab 6 is linked to the rest of the shell 2 by two tear lines 8,9, extending from the bottom edge 10 of the skirt 4 to a converging area 11, located on the top wall 3. The tear lines 8,9 are parallel on the skirt 4 and also parallel to the central axis A. They are curved from the rounded rim 13, which linked up the skirt 4 and the top wall 3, to the converging area 11.

These tear lines 8,9 can be made of continuous web as it is the case for the embodiment of the enclosed figures or of a discontinuous web (bridges). Such a web is thinner than the rest of the molded shell 4. More precisely, the thickness t^w is comprised between 0.3(t^mc) and 0.8(t^mc), wherein t^mc is the minimum thickness of the skirt or of the top wall. In this example, t^w = 0.35 mm and t^mc = 0.7 mm; t^w = 0.5(t^mc).

Said the parallel portions of the tear lines 8,9 on the skirt 4, define with the central axis A, a sector, the angle of which is of 48° in the present example.

The downwardly oriented appendix 7 of the tear tab 6 comprises a ring 12 which is intended to make the prehension easier for the tearing. As shown on Figure 4, the ring 12 is arched such that its free end be slightly outward.

The shell 2 (top wall 3 & skirt 4)

The skirt 4 which is annular of circular cross-section, extends from the rounded rim 13 which forms the circular outer periphery. The top wall 3 and the skirt 4 have respective inner faces 14, 15 defining a housing 16 for accommodating the neck finish 100 of the container (Figure 2), and respective outer faces 17, 18.

The cap 1 has also a plurality of ribs 30 extending parallel to the central axis A and equally distributed on the outer surface 18 of the skirt 4. The ribs 30 can present different lengths. In this example, the top ends 31 of these ribs 30 are arranged in a same plane which is perpendicular to the central axis A, and which is located at an equal distance from the top wall 3. These ribs 30 are intended to facilitate the grasping of the cap 1 by the bottling device on the industrial bottling line.

The inner face 14 of the top wall 3 can be coated with a sealing liner (e.g. a foam liner), the form of which is ring-like or disc-like.

The reversible opening/closing means 5

As illustrated in Figures 4 & 5, the inner face 14 of the skirt 4 is fitted out with inner threads 19 adapted to cooperate with corresponding outer threads 114 (shown on Figure 11) on the neck finish 100 of the container for sealingly closing this latter. These inner threads 19 of the cap 1 are the reversible opening/closing means 5.

The cap 1 is also equipped with non reversible means for fixing the cap 1 on the neck finish 100, namely the discontinuous beads 20 arranged in ring on the inner face 14 of the skirt beneath the inner threads 19 and close to the bottom edge 10 of the skirt 4. These discontinuous beads 20 are designed so as to fit into a groove 120 of complementary form placed on the outer face of the neck finish 100 of the container, as represented on Figure 11.

The discontinuous beads 20 can be introduced into the groove 120 of the neck finish 100 of the container, e.g. by force-fitting or snap-fitting.

The beads could be replaced by a continuous annular rib, except of course where the tear lines 8,9 go through the skirt 4 (see Figure 5), as it is also the case when beads 20 are discontinuous.

In some variants, the holes can be in the cap and/or the complementary projecting elements on the neck finish 100. The raw materials

The tear lines 8,9 are made of a thermoplastic material TPM different from another thermoplastic material TPM¹, which constitutes almost all the rest of the shell 2.

1 2

TPM is for instance high density polyethylene (HDPE) and TPM is for instance low density polyethylene (LDPE) or linear low density polyethylene (LLDPE). the following table gives

1 2

examples of suitable TPM & TPM designating by their commercial references.

LDPE & LLDPE are more tearable than HDPE due to their tensile strengths which are lower than those of the HDPE. It is advantageous that the whole of the shell 2 except the tear lines 8,9 (and possibly the tear tab) be in HDPE, because it insures a low deformation of the cap 1 when this latter is packaged in bulk for the transportation between its manufacturing site and its bottling site. A cap which is not deformed is a guarantee of a good processability during the industrial bottling, especially for screwed caps. The limited deformability also makes it possible to use the cap as non waterproof closing after the tearing of the tear tab 6.

HDPE has also a colour different from LLDPE or LDPE in this example. It makes it easier for the consumer to check whether the tamper-proof tear tab has been removed.

To further improve the appearance of the cap 1, the outer face 17 of the top wall 3 and/or the outer face of the skirt 4 could be provided with a pattern, a label, a design and/or an imprint or other. In this embodiment, a label 21 in LLDPE or LDPE of colour different from the HDPE, is overmolded on outer face 17 of the top wall 3.

The method for manufacturing the cap

The cap according to the invention can be obtained by a Multi Nozzle Injection Molding Process. In this example, there are three injection nozzles one for the HDPE, one for the LLDPE or LDPE of the tear lines 8,9 and one for the LLDPE or LDPE top label 21. That supposes LLDPE/LDPE and HDPE be together weldable.

Variants

The invention has been disclosed with a cap 1 presenting a symmetry of revolution with a circular top wall 3, an annular skirt 4 of circular cross-section. The invention is however not limited thereto and the cap 1 could be of any other suitable shape, the top wall 3, the skirt 4 and the tear tab 6 being adapted accordingly. The second embodiment shown on Figures 6-10 has the same references as the first embodiment of Figures 1-5. The second embodiment differs from the first in that the tear lines 8,9 extend from the bottom edge 10 of the skirt 4 only to the rounded rim 13 of the top wall 3, and in that the appendix 7 of the tear tab 6 is not outward curved and does not include a ring.

Claims

1. Cap (1) for closing the neck finish (100) of a container -preferably a bottle-, said cap (1) being molded from at least two different thermoplastic material TPM¹ and

TPM 2 , this latter being more tearable than TPM 1 , said cap (1) comprising:

a top wall (3),

an annular skirt (4) extending downward from the top wall (3) and having a bottom edge (10),

reversible opening / closing means (5) of the cap (1) on the neck finish (100) of the container, said means (5) being preferably screw thread means located inside the cap (1), and more preferably on the inner face (15) of the skirt (4),

means (20) for fixing the cap (1) on the neck finish (100) of the container, said means (20) being located inside the cap (1) on the inner face (15) of the skirt (4),

at least one tear tab (6):

^■ which is at least a part of the skirt (4),

^■ which comprises at least one, preferably at least two tear lines (8,9),

^■ and which is a pull and tamper-proof means;

the tear lines (8,9) extend between the bottom edge (10) of the skirt (4) and at least the top of the skirt (4);

at least the tear lines (8,9) and/or at least the tear tab (6) are made of TPM .

2. Cap (1) according to claim 1, wherein the tear lines (8, 9) extend between the bottom edge (10) of the skirt (4) and at least the top wall (3), on which at least one of the tear lines (8, 9) preferably continues inward.

3. Cap (1) according to claim 2, wherein the tear tab (6) is made of TPM and wherein the tear lines (8, 9) converge inward on the top wall (3) and join themselves.

4. Cap (1) according to claim 2 wherein the tear tab (6) is made of TPM¹ and the tear lines (8, 9) of TPM , wherein there are two tear lines (8, 9) converge inward on the top wall (3), the ends of said tear lines (8, 9) not joining themselves so as to leave a passageway (11) for the TPM¹ intended to form the tear tab (6) during molding.

5. Cap (1) according to at least one of any of the preceding claims, wherein at least one of said tear lines (8, 9) extending on the skirt (4), is substantially parallel to the axis (A) of the cap (1) or substantially perpendicular to the top wall (3).

6. Cap (1) according to at least one of any of the preceding claims, wherein TPM¹ is a polyolefm and more preferably a High Density PolyEthylene (HDPE) or a Linear Low Density PolyEthylene (LLDPE), and mixtures and/or alloys thereof.

TPM is a polyolefm and preferably a Low Density PolyEthylene (LDPE) or a Linear Low Density PolyEthylene (LLDPE), and mixtures and/or alloys thereof.

7. Cap (1) according to at least one of any of the preceding claims, wherein at least one tear line (8,9) is made of a web continuous or not, the thickness (t^w) of which is defined as follows with respect to the minimum thickness of the skirt (t^mc), in an increasing order of preference:

tw < _tmc . _tw_≤ o.₉₅(t^mc) ; _t ^w < 0.90(t^mc) ; t^w < 0.85(t^mc) ;

0.3(t^mc) < t^w < 0.8(t^mc).

8. Cap (1) according to at least one of any of the preceding claims, wherein the tear tab (6) has a sector comprised -in ° and in an increasing order of preference- between 10 and 90 ; 20 and 80 ; 30 and 70 ; 40 and 60.

9. Cap (1) according to at least one of any of the preceding claims, wherein the colour of the tear tab (6) and/or the colour of the tear lines (8,9) is(are) different from the colour of the rest of the cap (1).

10. Cap (1) according to at least one of any of the preceding claims, comprising at least one pattern, preferably at least one graphic pattern (21), said pattern(s) being preferably placed at least on the top wall (3), and preferably made of TPM .

11. Container -preferably a bottle- closed by a cap (1) according to at least one of any of the preceding claims.

12. Method for manufacturing a cap (1) according to at least one of any of the claims 1 to 10 comprising the steps of:

- molding, in a cavity of a mold, the part(s) of the cap (1) in TPM¹,

- overmolding, in the cavity of the mold, the part(s) of the cap in TPM , preferably at least one tear tab (6) and/or at least one tear line (8,9).