An opening arrangement for a container package

Abstract: The invention relates to an opening arrangement (1) for laminated container packages (2, 5) or cartons of the single-use disposable type. The opening arrangement (1) consists of an inner pouring spout (12) which constitutes a closed part continuous with the container package (2, 5), and an outer screw stopper-like sealing portion (4). Penetration devices (14) are provided in the outer sealing portion (4), the penetration devices severing the inner pouring spout (12) when the package is opened.

Description: The present invention relates to an opening arrangement for container packages, comprising a sealing portion inflexibly engaging with and surrounding a pouring spout, whose end facing away from said container package in accordance with the preamble of claim 1. Container packages or cartons of the single-use disposable type are largely employed today to pack consumer goods such as, for example, beverages like milk or juice. The container package is made from a laminate with carrier layers of paperboard or cardboard, different layers of thermoplastic being laminated thereto. The laminate may also have a different core material, such as metal foil. The packaging material, which may be in web form or as sheet blanks, is folded, sealed and finally formed into a liquid-tight container package. The finished container package should naturally also include an opening arrangement which must be simple to open and pour from, with the liquid contents in a compact jet and without any risk of spilling or dripping. However, it has proved that container packages manufactured from a packaging material consisting of a paper laminate may be difficult to tear open and fold to form a functional pouring spout. Moreover, when the intention is to reclose and reseal the container package, it is not possible to make the package liquid-tight once again. It is also known in the art to manufacture container packages whose main portion consists of a packaging laminate in accordance with the above description, but whose upper defining surface consists of an injection moulded thermoplastic lid. The thermoplastic lid also includes an opening arrangement integral with the lid. This opening arrangement is relatively easy to open but neither is this version liquid-tight on re-closure and resealing. In order to obviate the above-outlined drawbacks, various forms of penetrating screw stoppers or plugs have been produced which are intended to be placed on the surface of the container package so that the screw plug penetrates through the surface layer when the package is opened. It is further known in the art to form a partly integrated pouring spout from the surface of the packaging material. The pouring spout is surrounded by a sealing portion of the so-called screw stopper or plug type which, on being opened, tears off an outer portion of the pouring spout. That part of the pouring spout which is torn off during the opening operation has been sealed against the outer sealing portion by means of heat. As a result, the tear-off operation generally entails that the pouring spout has no smooth outer edge, which may render difficult pouring of the contents enclosed in the container package. An arrangement according to the preamble of claim 1 is described in EP-A-0 039 374. However, in spite of a complicated and expensive production thereof there are problems when the filling good is to pour out of the pouring spout. It is an object of the present invention to realize an opening arrangement for container packages which is easy to be produced and on opening makes it possible for the aperture of the pouring spout to have smooth edges. The invention is claimed in claim 1. Preferred embodiments of the present invention have further been given the characterizing features as set forth in sub-claims. One preferred embodiment of the present invention will now be described in greater detail hereinbelow with particular reference to the accompanying drawings, in which: Figure 1 is a perspective view of an opening arrangement according to the present invention in a container package of known type; Figure 2 is a perspective view of the opening arrangement according to the present invention in another type of container package; Figures 3A-E show stepwise and partly in section how an opening arrangement according to the present invention is applied to a container package according to figure 1; Fig. 4 shows a top plan view of an opening arrangement according to the present invention; and Fig. 5 is a side elevation partly in section of the opening arrangement according to the present invention. The Drawings show only those details essential to an understanding of the present invention. DESCRIPTION OF PREFERRED EMBODIMENT Fig. 1 shows an opening arrangement 1 according to the present invention applied to a container package 2 of known type. The container package 2, which is manufactured from a laminate with a core of paper, cardboard or metal to which is laminated different layers of thermoplastic, is folded, sealed and formed into a so-called gable-top carton 2. The opening arrangement 1 is placed on one of the upper defining surfaces 3 of the carton 2 forming a so-called gable-top. The Figure shows only the outer sealing portion 4 of the opening arrangement 1, this portion being formed as a screw cap of substantially conventional type, with interior threading, or alternatively a snap top with an inner bead (not shown). Fig. 2 shows another type of container package 5 also of known type in which the lower portion of the container package 5 consists of a laminate in accordance with the above description. The upper defining surface 6 of the container package 5 consists of a thermoplastic panel, part of the surface of which has been formed into a pouring spout surrounded by an outer sealing portion 4. The remaining parts of the thermoplastic panel are folded about the upper edge of the container package 5 and are sealed by means of heat against the thermoplastic surface of the packaging laminate. Figs. 3A-E schematically show how an opening arrangement 1 according to the present invention is realized in a container package 2 according to Fig. 1. A circular opening 7 (Fig. 3A) is made in one of the upper sloping gable-top panels 3 of the container package 2. A thermoplastic panel 8 is placed inside the circular opening 7, this panel having a diameter which exceeds that of the circular opening 7 in the wall surface 3 of the container package 2. As shown in Fig. 3B, the thermoplastic panel 8 is sealed interiorly against the inner wall surface of the container package 2 by means of a sealing tool 9. In Fig. 3C, the thermoplastic panel 8 is heated to a temperature at which the thermoplastic plasticizes (for polyethylene approx. 110°C) with the aid of a heater 10. Once the thermoplastic panel 8 has become plasticized and pliable, it is subjected to vacuum or pressure forming in a moulding tool 11 as illustrated in Fig. 3D. The outer sealing portion 4 acts as a mould for the vacuum forming, i.e. the screw cap which is to surround the pouring spout 12. Fig. 3E finally shows the finished pouring spout 12 provided with threads 15. The pouring spout 1 is completely sealed and constitutes a liquid-tight part of the container package 2 when the outer sealing fin or flap 13 is finally sealed together after the filling operation. Figs. 4 and 5 show the outer sealing portion 4 from two different views. The outer sealing portion 4 substantially consists of a conventional screw cap but there are provided, in its upper region, at least two, but preferably four penetration devices 14. These penetration devices 14 may consist of small bevelled plastic pieces which project out from the inner surface of the peripheral wall of sealing portion 4. They may also consist of small metal pieces which have been fixed in place and which, on opening of the opening arrangement 1, easily penetrate the upper portion of the pouring spout 12. In the vacuum forming of the pouring spout 12, when the outer sealing portion 4 serves as a mould, the plasticized thermoplastic will form itself about the penetration devices 14 without the plastic cracking or being severed in this position. By employing four penetration devices 14 placed at mutually different levels, there will be obtained, on removal of the outer sealing portion 4, an even and horizontal outer edge of the pouring spout 12. That part of the pouring spout 12 which is severed in the opening operation will be retained by the penetration devices 14 in the upper region of the sealing portion 4. The number of penetration devices 14 is dependant upon the length and pitch of the thread 15. The longer the thread 15, the fewer will be the number of penetration devices 14 required. The penetration devices 14 must together be capable of cutting off a complete circular surface of the upper region of the pouring spout 12. As a modified embodiment of the present invention, it is possible, in association with the outer sealing portion 4, to place a removable ring of plastic which is secured or sealed to the edge of the pouring spout 12. This pull-ring is torn off before opening of the opening arrangement 1 proper and thereby constitutes a safeguard against the unauthorized opening of the container package 2, 5. As will have been apparent from the above description, the present invention realizes an opening arrangement for conventional container packages or cartons which is simple to open and reseal. The opening arrangement is furthermore relatively cheap to manufacture and, as a result of the penetration devices characteristic of the present invention, the user will obtain a pouring spout which makes possible pouring of the contents of the container package without spilling and without dripping. The present invention should not be considered as restricted to that described above and shown on the Drawings, many modifications being conceivable without departing from the scope of the appended Claims.

Claims: An opening arrangement for a container package (2, 5) comprising a sealing portion (4) having a peripheral wall inflexibly engaging with and surrounding a pouring spout (12) whose end facing away from said container package (2, 5) which pouring spout (12) consists of a liquid-tight material layer tightly attached to said container package (2, 5) and which sealing portion (4) comprises a penetration device for penetrating into said pouring spout (12), characterized in that said pouring spout (12) is formed by moulding into said sealing portion (4) and about said penetration device which comprises at least two penetration elements (14) arranged in the upper region of said sealing portion (4) and on the peripheral wall thereof. Opening arrangement as claimed in claim 1, characterized in that said penetration elements (14) are placed on different levels within the sealing portion (4). Opening arrangement as claimed in claim 1 or 2, characterized in that said penetration elements (14) are four in number. Opening arrangement as claimed in one of the preceding claims, characterized in that said sealing portion (4) is a screw cap. Opening arrangement as claimed in one of the preceding claims, characterized in that a ring is provided for said sealing portion (4) said ring being secured against the edge of the pouring spout (12) and intended to be removed before opening of the container package (2, 5). Opening arrangement as claimed in one of the preceding claims, characterized in that said pouring spout (12) is made of a material which includes layered thermoplastic. Opening arrangement as claimed in claim 6, characterized in that the thermoplastic material constitutes a part of the upper end wall (6) of the container package (5). Opening arrangement as claimed in claim 6 or 7, characterized in that said pouring spout (12) comprises polyethylene. Opening arrangement of claims in one of the preceding claims, characterized in that said penetration elements (14) are formed as bevelled pieces projecting out from the inner surface of the peripheral wall of said sealing portion (4).

Inventors: BERGGREN GOERAN, NEDSTEDT ULF, BERGGREN, GOERAN, NEDSTEDT, ULF, Berggren, Göran
Applicants: TETRA LAVAL HOLDINGS & FINANCE, TETRA LAVAL HOLDINGS & FINANCE SA
Application year: 1992
Main classification: B65D51
IPC codes: B65D51, B65D5