[0001] The present invention relates to a container of flexible material, particularly for
liquid, viscous or granular products.
[0002] Containers of the above type, made of flexible single-layer or multi-layer material,
with one or both outer surfaces heat sealable, for example of polyethylene, are known
and obtained by successive folding and sealing, normally from a double film.
[0003] These containers, also known as stand-up containers, normally have a widened, reinforced
base and are tapered towards the top.
[0004] The main drawback of these containers, especially when they are used to contain liquid
or viscous substances, is that they tend to swell because of the pressure exerted
by the product contained inside them on the flexible side walls of the container.
[0005] This type of swelling or bulging is very unsightly and makes it difficult to read
the writing on the package. Another drawback related to this problem is the increase
in the crosswise measurement of the container. Moreover, the mechanical strength of
the package can be reduced.
[0006] The aim of the invention is to eliminate the aforementioned drawbacks, providing
a container of flexible material for liquid, viscous or granular products, that maintains
a perfectly upright position under any condition, avoiding crosswise swelling.
[0007] A second aim of the invention is to provide the package with greater stability, both
when it is full and during the subsequent emptying stage.
[0008] Another aim of the invention is to provide such a container that can be made simply
and economically.
[0009] These aims are achieved with the container according to the invention which has the
features of appended independent claim 1.
[0010] Preferred embodiments of the invention are described in the subsequent claims.
[0011] Substantially, the container according to the invention is prepared with at least
one inner reinforcement, which prevents the opposite side walls from separating beyond
a certain limit when the container is filled with product.
[0012] This reinforcement advantageously consists of a tubular element or sleeve, which
is placed inside the container and fixed by means of two respective weld lines to
each of the two opposite side walls of the container.
[0013] In a simplified form, each reinforcing element could consist of a diaphragm with
the ends welded to the two opposite side walls of the container, diaphragm which lies
folded inside the container when the container is in the flattened state, before filling,
and spreads out, allowing a maximum widening of the container corresponding to its
length, when the container is filled.
[0014] For large-sized containers, a plurality of reinforcing elements are placed, in order
to avoid possible swelling in areas at a distance from that where a single reinforcing
element would be situated.
[0015] Further characteristics of the invention will be made clearer by the detailed description
that follows, referring to a purely exemplary and therefore non-limiting embodiment,
illustrated in the appended drawings, in which:
Figure 1 is a schematic side elevation of a container provided with a reinforcing
element according to the invention, shown in the flattened state, before filling;
Figure 2 is an axonometric view of the container in Figure 1, after filling;
Figure 3 is a similar view to that in Figure 1, of a larger-sized container, provided
with two reinforcing elements;
Figure 4 is an axonometric view of a reinforcing element of the container according
to the invention, shown in the folded state;
Figure 5 is an axonometric view of the reinforcing element in Figure 4, in the opened
state of use.
[0016] In Figures 1 and 2, the container according to the invention has been indicated as
a whole with reference numeral 1. It is a container for liquid, viscous or granular
products, also known as a stand-up container, made of flexible material in one or
more layers, heat-sealable on at least one surface.
[0017] The container 1 has a standing base 2 and two opposite facing side walls 3, each
welded to a respective half-perimeter 4 of the base 2, and welded to each other at
the side edges 5 and the upper edge 6, after filling. The container 1 thus takes on
an upward tapering shape.
[0018] In the example shown, the two opposite facing side walls 3 are not perfectly squared,
that is with their side walls at right angles to the base, but slope inwards, so that
the container 1, when filled, takes on a substantially conical shape.
[0019] In Figure 1, the container 1 is shown in the flattened form, that is with the base
2 folded and the two opposite side walls 3 touching each other, whilst in Figure 2
the container is shown in the condition of use, after filling.
[0020] The container 1 shown in figures 1 and 2 is a container for liquids, and for this
purpose it is provided with a pouring nozzle 7 in the upper part of one of its side
edges 5, whilst on the opposite side it is provided with a carrying handle 8, formed
by making an opening in the corresponding welded strip 5, suitably wider than that
in which the nozzle 7 is provided.
[0021] It is obvious that the type of container shown in Figures 1 and 2 is purely exemplary,
and that other forms and constructions are possible, within the scope of the inventive
solution that will be described below.
[0022] Thus, for example, Figure 3 shows a container having a greater width than that of
Figures 1 and 2, and provided with an upper handle. In Figure 3 the same reference
numerals as in Figures 1 and 2 have been used to indicate similar or like elements.
The essential difference between the two types of containers illustrated is that in
the one in Figure 3 two reinforcing elements 10 are used, which will now be described,
instead of one as in the embodiment in Figures 1 and 2.
[0023] According to the invention, in fact, to eliminate the problems set out in the introduction,
related to swelling of the container, at least one reinforcing element 10 is provided,
shown in isolation in Figures 4 and 5, and substantially shaped like a sleeve or tubular
element, with two opposite surfaces 11, which are heat sealed by means of two respective
weld lines 12, to the corresponding opposite walls 3 of the container 1, inside which
said reinforcing elements 10 are housed.
[0024] The material forming the reinforcing elements 10 is also a flexible single-layered
or multi-layered material, with at least one surface of heat-sealable material, such
as polyethylene or the like, to allow welding to the corresponding walls 3 of the
container 1.
[0025] The two weld lines 12 are advantageously arranged so as to diverge slightly towards
the top, as shown in the appended figures, so as to allow the container a greater
resistance to swelling.
[0026] As shown in Figure 4, when the container 1 is flattened, before filling, the reinforcing
element 10 is also flattened, folding around two opposite fold lines 20 substantially
positioned at the midline of the other two opposite surfaces 21 of the reinforcing
element 10, causing the maximum separation between the two opposite side walls 3 of
the container 1 during use.
[0027] Figure 5, on the other hand, shows the reinforcing element 10 in the open position,
after filling of the container 1.
[0028] During filling of the container from above, that is before heat sealing along the
upper edge 6 of the container, the tubular reinforcing element 10 does not cause any
impediment to passage of the product, whether liquid, viscous or granular, whilst
after filling, by taking on the shape shown in Figure 5, it prevents the opposite
walls 3 of the container form separating from each other by a distance greater than
that of the surfaces 21 of the reinforcing element 10, thus avoiding troublesome swelling
or bulging of these types of containers.
[0029] By making the reinforcing elements 10 of a suitable shape, the container 1 can be
made to take on the desired shape, after filling, always avoiding problems of swelling
of the container.
[0030] In the embodiment in Figure 3 two reinforcing elements 10 arranged side by side are
provided, because of the greater width of the container 1.
[0031] In a simpler embodiment, the reinforcing element can be replaced by a simple diaphragm
or membrane, substantially corresponding to one of the surfaces 21 of the element
illustrated in Figure 4 and 5, the opposite ends of which are welded to the opposite
walls 3 of the container 1.
[0032] In this case, a larger number of reinforcing elements will normally be necessary
to ensure that the container keeps its shape, without swelling.
[0033] The reinforcing elements 10 according to the invention are inserted in the container
during the production cycle thereof, between the two films destined to form the two
opposite walls 3 of the container, and the weld lines 12 are advantageously made from
the outside of the container.
[0034] The reinforcing elements 10 give the container greater stability thanks to the beam
effect attributable to the inner connection between the two opposite walls 3.
[0035] From what is described the advantages of the arrangement proposed by the invention
are clear, though it must not be considered restricted to what is described and illustrated
above, but solely to the content of the claims that follow.
1. A container of flexible material, particularly for liquid, viscous or granular products,
having a standing base (2) from which rise at least two opposite walls (3) joined
around the perimeter to each other and to said base (2), characterized in that it
comprises on its inside at least one reinforcing element (10) fixed to said opposite
walls (3), the length of said reinforcing element (10) determining the greatest separation
of said walls (3) with respect to each other in the area in which it is situated.
2. A container according to claim 1, in which said reinforcing element (10) comprises
a flexible membrane made of sheet material, the ends of which are welded to said opposite
walls (3) of the container (1) along respective weld lines (12) extending substantially
in the direction of the height of the container (1).
3. A container according to claim 1, in which said reinforcing element (10) comprises
a sleeve or tubular element of flexible sheet material, having two opposite surfaces
(11), welded to the corresponding walls (3) of the container (1) by means of two respective
weld lines (12) which extend essentially along the height of the container (1), said
opposite surfaces (11) being connected one to the other by means of a further pair
of opposite surfaces (21), starting from said weld lines (12).
4. A container according to claim 3, characterized in that each pair of weld lines (12)
between a surface (11) of the reinforcing element (10) and the corresponding wall
(3) of the container (1) is arranged so as to diverge slightly towards the top.
5. A container according to claim 3 or 4, characterized in that said reinforcing element
(10) lies flattened inside the container 1, before filling, folded around fold lines
(20) situated substantially at the midlines of said surfaces (21) connecting said
opposite surfaces (11).
6. A container according to any one of claims 3 to 5, characterized in that said surfaces
(21) of the reinforcing element (10) have an upward tapering shape.
7. A container according to any one of the preceding claims, characterized in that it
is provided with a carrying handle (8).
8. A container according to any one of the preceding claims, characterized in that it
is provided with a pouring nozzle (7).
9. A reinforcing element for containers of flexible material for liquid, viscous or granular
products, comprising a base (2) and at least two opposite walls (3) rising from the
perimeter of said base (2) and joined to each other around the perimeter, characterized
in that it comprises a sleeve or tubular element housed inside said container (1)
and having two opposite surfaces (11) welded, by means of two respective weld lines
(12) extending substantially upwards, to said opposite walls (3) of the container
(1), and joined to each other by two respective opposite surfaces (21) the width of
which determines the maximum permissible separation for said walls (3) of the container
(1).
10. A reinforcing element according to claim 9, characterized in that each pair of said
welding lines (12), which join one surface (11) of the reinforcing element (10) to
the corresponding wall (3) of the container (1), diverges slightly towards the top.