EP2441698A1

EP2441698A1 - Bag for fruit and vegetable produce

Info

Publication number: EP2441698A1
Application number: EP09845741A
Authority: EP
Inventors: José María MESEGUER HUERTAS
Original assignee: Cristobal Meseguer SA
Current assignee: Cristobal Meseguer SA
Priority date: 2009-06-09
Filing date: 2009-10-13
Publication date: 2012-04-18
Anticipated expiration: 2029-10-13
Also published as: PL2441698T3; EP2441698B1; ES2356876A1; WO2010142817A1; ES2356876B1; EP2441698A4; ES2481669T3

Abstract

The bag of the invention is of the type constituted by means of a continuous band that is closed on itself by means of a longitudinal weld line, thereby defining a tubular body that can be divided up into modules corresponding to respective bags, in which, in said continuous band, there are longitudinal strips of non-mesh plastic alternating with longitudinal mesh strips, which are superposed in the edge regions thereof for joining to one another. The invention focuses on the fact that whilst the non-mesh strips are made from polyethylene the mesh strips are made from bioriented polypropylene, the continuous band incorporating, in correspondence with each line of superposition between the aforesaid strips, a narrow strip that is likewise made from polyethylene, adapted to the polypropylene mesh, which welds with the aforesaid longitudinal, wider strips of polyethylene via the holes in the mesh, fixing the latter. In this way, construction of the bag requires less raw material.

Description

OBJECT OF THE INVENTION

The present invention relates to a bag of the type used for packaging and selling fruit and vegetable produce, such as citrus fruit, potatoes, etc., although the bag can be used in any other field where similar features are required.
The object of the invention is to obtain a bag that offers suitable features from the point of view of mechanical resistance, requiring fewer raw materials for its construction, with the ensuing and beneficial repercussion of this from a financial point of view.

BACKGROUND OF THE INVENTION

Certain types of fruit and vegetable products, such as potatoes, have been sold for a long time in plastic bags having a reticular structure, which allow airing at the same time as direct viewing of the product. On occasions and in order to obtain these bags, a tubular mesh body is used that is closed at both ends after placing the product inside, generally one of such ends may be provided with a handle to facilitate the consumer carrying it by hand after making the purchase.
On other occasions a continuous, laminar, strip is used, which closes over itself to configure the aforesaid tubular body, by means of a longitudinal seal, following which the aforementioned process is repeated.
The common problem with this type of bag centres on the fact that the mesh body is incapable of receiving printed information, which is essential in the immense majority of cases, given that the bag itself needs to identify the product brand, characteristics thereof, barcode, etc.
One solution to this problem is shown in Utility Model U 9701734, held by the applicant in question, and consisting of the use of a continuous band, structured on the basis of a longitudinal intermediate strip or band of continuous plastic, having a considerable width, capable of carrying printed information, two side sections in respect of the aforesaid intermediate band, also made of plastic, but having a reticular structure, specifically on the basis of a three-thread mesh, these sections being secured to the intermediate one by means of linear and longitudinal welds in correspondence with their superposed edges, the band being complemented with another two sections or strips of marginal continuous and narrow plastic, designed also to partially overlap along their free edge and to be secured together by means of a longitudinal weld, in order to define the tubular body, subsequently dividable into sections or bags that close at their ends after receiving inside the contemplated dose of produce.
As may be inferred from the foregoing, the indispensable requirement for obtaining a bag such as that of Utility Model U 9701734, is for the plastic material constituting the different longitudinal sections or strips that participate in the band, in other words the continuous strips and the reticular strips, to be made of compatible materials for joining through heat-sealing.
More specifically, the mesh is made of low-density polyethylene and the sheet is closed with medium density polyethylene.
For the mesh to have a suitable resistance and given its own nature, the PE (polyethylene) must have a minimum weight which may be established in the region of 70 g/m².
This means that the bag in question, perfectly valid from the theoretical point of view insofar as it meets the basic requirements made of it, in practice cannot be used for certain products, such as citrus fruit, because it is not competitive in the market compared to conventional solutions, precisely due to the amount of material required for the manufacture thereof.
The apparently obvious solution to this problem is to use meshes on the basis of materials which, while having a high degree of resistance, may be very light, in such a way that the amount of materials participating in the bags is minimal, as occurs in the case of biaxially-oriented polypropylene.
However, this apparent solution is not viable in practice insofar as the biaxially-oriented polypropylene cannot be welded to polyethylene, at least with the level of mechanical resistance that is necessary, in such a way that the securing between the longitudinal strips contemplated in Utility Model U 9701734 is not viable using these materials.
Nor is it feasible to replace the polyethylene sheets that participate in the aforesaid Utility Model with sheets of biaxially-oriented polypropylene, in other words sheets of the same material as that which constitutes the meshes, because biaxially-oriented polypropylene doesn't weld to itself either, at least in an effective manner.

DESCRIPTION OF THE INVENTION

The bag for fruit and vegetable produce proposed by the invention definitively resolves the problems set out above, allowing on the basis of a basic structure such as that shown in Utility Model U 9701734 the use of medium density polyethylene to obtain closed bands that participate therein, and biaxially-oriented polypropylene to obtain sections of mesh, leaving all sections solidly joined to each other.
To this effect and more specifically the invention consists of incorporating in the continuous band constituting the basic element for forming the bags, in other words the continuous band in which the strips or bands of medium density polyethylene participate and biaxially-oriented polypropylene, narrow strips of polyethylene which overlap the sections of biaxially-oriented polypropylene in correspondence with the zones where the aforesaid sections of biaxially oriented polypropylene overlap in turn with the medium density polyethylene strips, thereby obtaining a sort of sandwich based on two layers of polyethylene which are directly welded to each other with the interposition of the polypropylene mesh.

DESCRIPTION OF THE DRAWINGS

To complement the description provided herein and with a view to contributing to a better understanding of the characteristics of the invention, in accordance with a preferred example of a practical embodiment thereof, a set of drawings is included as an integral part of said description, which by way of illustration but not limitation, represent the following:

fig. 1: shows, according to a partial view in perspective, the continuous band used as the basis for obtaining the bag for fruit and vegetable produce that constitutes the object of the present invention;
fig. 2: is a close-up in cross-section of the same band;
fig. 3: shows an elevated rear view of the bag formed using the band of figure 1;
fig. 4: shows a close-up cross-section view of the bag of figure 3;
fig. 5: shows, finally, a similar representation to that of figure 1 but corresponding to a variation in the embodiment of the continuous band.

PREFERRED EMBODIMENT OF THE INVENTION

In view of the aforesaid drawings it can be observed that the disclosed bag is obtained on the basis of a continuous band (1), wherein an intermediate longitudinal strip (2) is established made of medium density polyethylene, capable of carrying any type of printed information (3), overlapping with the edge regions of the aforesaid strip (2) there are sections (4-4') which as previously are made of biaxially-oriented polypropylene structured in the form of a mesh, strips (4-4') which through their opposite edge region overlap in turn with the edge region of other strips (5-5') made of the same polyethylene as the intermediate strip (2) and having approximately half the width of the latter.
On the edge regions of these strips (2, 4 and 5) which are superposed, narrow strips (6) are in turn superposed also made of medium density polyethylene, strips (6) which are specifically superposed on strips (4-4') of the mesh of biaxially-oriented polypropylene, in such a way that when pressure and heat are applied to the continuous band (1) in these regions of superposition, the strips (2 and 5) are solidly joined through welding to the narrow strips (6) through the empty spaces of the meshes (4-4') as may be especially observed in figure 2, in such a way that the different components of the continuous band (1) are solidly joined to one another.
Obviously the invention is applicable in the same way to a continuous band (1), such as shown in figure 5, which instead of presenting on both sides of the intermediate longitudinal strip (2) of polyethylene a symmetrical structure as in the case of figure 1, presents an asymmetrical structure in such a way that on both sides thereof are situated respective sections (4-4') of biaxially-oriented polypropylene, and only on one of these meshed sections (4) another longitudinal strip (7) of a material and size coinciding with those of the central strip (2).
As of this point and as is conventional, the continuous band (1) closes on itself becoming a tubular body, in which edge, longitudinal and free regions of the strips (5-5') or (4'-7) are superposed and fixed by welding, with the participation of aforementioned narrow strips (6), tubular and continuous body that, as is also conventional, is divided into portions such as the one shown in figure 3, corresponding to respective units or bags that conveniently close at their ends.

Claims

Bag for fruit and vegetable produce, of the type constituted by means of a continuous band that closes on itself by means of a longitudinal weld line, thereby constituting a tubular body that can be divided up into modules corresponding to respective bags, and in which, in said continuous band, there are longitudinal strips of non-mesh plastic, alternating with longitudinal mesh strips, which are superposed in the edge regions thereof for joining to one another, characterised in that whereas the strips of non-mesh plastic are made of polyethylene, the mesh strips are made of biaxially-oriented polypropylene, the continuous band incorporating in correspondence with each line of superposition between the aforesaid strips, a narrow strip that is likewise made of polyethylene, adapted to the polypropylene mesh, which welds with the aforesaid longitudinal wider strips of polyethylene through the holes in the mesh, fixing the latter.
Bag for fruit and vegetable produce, according to claim 1, characterised in that when the continuous band presents edge strips of a different nature, in other words a strip of biaxially-oriented polypropylene and another strip of polyethylene, these join to transform the continuous band into a tubular body by means of another narrow strip of polyethylene.