BACKGROUND ART Many pourable food products, such as fruit juice, pasteurized of UHT (ultra-high-temperature processed) milk, wine, tomato sauce, etc., are sold in packages made of sterilized packaging material.

A typical example of such a package is the parallelepipedal package for liquid or pourable food products known as Tetra Brik Aseptic (registered trademark), which is formed by folding and sealing laminated strip packaging material. The laminated packaging material comprises layers of fibrous material, e. g. paper, covered on both sides with thermoplastic material, e. g. polyethylene; and, in the case of aseptic packages for long-storage products, such as UHT milk, the side of the packaging material eventually contacting the food product in the package also has a layer of

barrier material, such as an aluminium film, which in turn is covered with one or more layers of thermoplastic material.

As is known, such packages are produced on fully automatic packaging machines, on which a continuous tube is formed from the strip-fed packaging material; the strip of packaging material is sterilized on the packaging machine, e. g. by applying a chemical sterilizing agent, such as a hydrogen peroxide solution; following sterilization, the sterilizing agent is removed, e. g. vaporized by heating, from the surfaces of the packaging material; and the strip of packaging material so sterilized is kept in a closed sterile environment, and is folded and sealed longitudinally to form a tube.

The tube is then filled with the sterilized or sterile-processed food product, and is sealed and cut at equally spaced cross sections into pillow packs, which are subsequently folded mechanically to form finished, e. g. substantially parallelepipedal, packages.

The finished package comprises an opening device, which in turn normally comprises an opening formed in a wall of the package, and a closing device made of plastic material and fitted to the wall of the package to cover the opening in a closed configuration. Inwards of the closing device, the opening is normally also sealed by a pull-off tab sealed to the packaging

material and which, when the closing device is opened, must be removed to pour out the content of the package.

On account of the opening device and the small size of the pour opening, packages of the above type are unsuitable for use with dense, semifluid pourable food products, such as yogurt or cream, or with solidified pourable food products, such as cheese, which are poured into the package in the liquid state and eventually set inside the package. Opening devices of the type described above, in fact, make it extremely difficult to pour semifluid food products through the respective openings, and, more importantly, do not allow for consuming semifluid or solidified food products directly from the package, as called for by nature of such products.

From Patent EP-A-779222, sealed packages for pourable food products are also known wherein the opening device is defined by a pull-off tab, which is sandwiched and heat sealed between two superimposed lateral edges of the packaging material forming a longitudinal seal line of the package, and has an end grip portion projecting laterally with respect to the longitudinal seal line. The tab is pulled off crosswise to the seal line, and removal is guided by two V-shaped cuts, which are formed on the upper lateral edge of the packaging material forming the seal line, and are located on opposite sides of the tab. Alternatively, the

tab is pulled off along a transverse preferential tear strip defined laterally by two parallel perforated lines formed in the packaging material and extending from the tab.

In both cases, opening the package as described results in partial or total damage of the package, which therefore cannot be used to consume the semifluid or solidified food product directly from the package.

DISCLOSURE OF INVENTION It is an object of the present invention to provide a sealed package for pourable food products, designed to eliminate the aforementioned drawbacks typically associated with known packages.

According to the present invention, there is provided a box-shaped sealed package for pourable food products, having end walls, lateral walls and major walls; said package comprising pull-off opening means at least on one of said walls, and being made from a tube of multilayer packaging material in sheet form sealed and cut along equally spaced cross sections ; and said opening means comprising a preferential tear line involving part of the thickness of the multilayer packaging material; characterized in that said preferential tear line is formed at least on one of said major walls, and defines an opening area of said package of an extension comparable with that of the major wall, and a gripping member connected integrally to said

opening area and extending outwards of said package.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred, non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows a view in perspective of a sealed package for pourable food products in accordance with the present invention; Figure 2 shows a larger-scale top plan view of an opening device of the Figure 1 package; Figure 3 shows a section along line III-III in Figure 2; Figure 4 shows a section along line IV-IV in Figure 3; and Figure 5 and 6 show larger-scale sections, illustrating the component layers, of different embodiments of the material forming the Figure 1 package.

BEST MODE FOR CARRYING OUT THE INVENTION Number 1 in Figure 1 indicates as a whole a sealed package for pourable food products in accordance with the present invention.

Package 1 is made from a tube of sheet packaging material sealed and cut along equally spaced cross sections, as described previously in detail.

The packaging material has a multilayer structure (not shown) and, when used for packaging pasteurized

products (e. g. yogurt, cream and other cold-storage products), comprises a layer of fibrous material 30, normally paper, covered on both sides with respective layers of thermoplastic material 31,32, e. g. polyethylene (Figure 5). When used for aseptic packaging of long-storage products, the side of the packaging material eventually contacting the food product in package 1 also has a layer of barrier material 33, e. g. aluminium, in turn covered with one or more layers of thermoplastic material 34 (Figure 6).

Package 1 is substantially in the form of a parallelepipedal box with end walls la, lateral walls lb and major walls 2, and comprises a pull-off opening device 3 on one major wall 2.

According to the present invention, device 3 comprises a closed preferential tear line 4 formed on wall 2 and defining an opening area 4 of package 1 of an extension comparable with that of wall 2, and a gripping member 6 connected integrally to opening area 5 and extending outwards of package 1.

More specifically, preferential tear line 4, which involves part of the thickness of the multilayer packaging material, is pentagonal and defined by a succession of perforations. More specifically, opening area 5 defined by preferential tear line 4 is defined by a rectangular portion 7 and by an isosceles triangular portion 8 extending from a major side of portion 7.

The preferential tear line 4 is advantageously formed using a laser cutting device (not shown) of the type described, for example, in European Patent EP-B1- 357,841.

In the case of packaging material for pasteurized products (figure 5), laser cutting involves the outer layer of thermoplastic material 31 and at least part of the layer of fibrous material 30 ; whereas, in the case of packaging material for aseptic packages (Figure 6), laser cutting stops at the layer of barrier material 33, and therefore involves the layer of fibrous material 30 and both the layers of thermoplastic material 31,32 contacting the layer of fibrous material 30.

With particular reference to Figures 2 to 4, gripping member 6 is made of plastic material, is applied to a substantially triangular through opening 9 in wall 2, and is preferably formed by injecting plastic material through opening 9 between two mold elements (not shown) cooperating mutually on opposite sides of opening 9.

Gripping member 6 extends from portion 8 of opening area 5, close to a vertex of preferential tear line 4.

Gripping member 6 comprises a base portion 10 located inside package 1 and having a substantially triangular contour extending outwards with respect to a lateral edge 11 of opening 9 ; and an actuating portion 12 connected integrally to base portion 10 and located

outside package 1, so that a surrounding region of opening 9 is interposed between base portion 10 and actuating portion 12.

More specifically, actuating portion 12 comprises a substantially triangular mating portion 15 cooperating with the surrounding region of opening 9, on the opposite side to base portion 10, and having a contour extending outwards with respect to lateral edge 11 of opening 9 and inwards with respect to the contour of base portion 10. Actuating portion 12 also comprises a substantially flat lever portion 16 projecting from mating portion 15 and having an end 17 projecting laterally with respect to package 1.

Base portion 10 and mating portion 15 of gripping member 6 are joined by a connecting portion 18 engaged inside opening 9.

Finally, base portion 10, mating portion 15 and connecting portion 18 define a substantially triangular recess 19 facing inwards of package 1.

The advantages of package 1 according to the present invention will be clear from the foregoing description.

In particular, by virtue of opening area 5 extending over substantially the whole of wall 2, package 1 permits direct consumption from the package of semifluid food products such as yogurt or cream, and solidified products such as cheese, which is poured in

the fluid state into package 1 in the making, and eventually sets inside the finished package 1.

Moreover, opening device 3 is of straightforward design and easy to produce.

Clearly, changes may be made to package 1 as described and illustrated herein without, however, departing from the scope of the accompanying Claims.

In particular, gripping member 6 may be replaced by a pull-off tab sealed to the packaging material defining wall 2.

Also, preferential tear line 4 and, consequently, opening area 5 may extend partly over a wall of package 1 adjacent to wall 2.