EP1454837A1

EP1454837A1 - Continuous mesh tube which is used to produce bags for vegetable and fruit products or similar products

Info

Publication number: EP1454837A1
Application number: EP02787984A
Authority: EP
Inventors: Juan Altimira Fontcuberta
Original assignee: Inciativas Barlar SL
Current assignee: Preformados Tubulares SL
Priority date: 2001-11-23
Filing date: 2002-11-22
Publication date: 2004-09-08
Also published as: ES2197780B1; AU2002352279A1; ES2197780A1; WO2003043896A1

Abstract

A continuous sheath of mesh for forming bags for fruit and vegetable products and the like, which sheath (1) is provided with at least one pair of longitudinal laminar bands of plastic running along the length of the tubular wall, one band (2a) inside and the other one (2b) outside, in coinciding positions and joined to one another in order to fix between them the structure of the mesh strip situated between said bands.

Description

OBJECT OF THE INVENTION

The present invention refers to a continuous sheath of mesh for forming bags for fruit and vegetable products and the like by means of transverse welding and cutting lines.
The object of the invention consists of providing the tubular band of mesh with laminar bands of plastic susceptible to receiving printed information concerning its contents, while at the same time acting as a reinforcement.

BACKGROUND OF THE INVENTION

Bags for fruit and vegetable products, such as oranges, lemons, potatoes, etc., are already known on the market, constituted of a tubular body of woven or extruded mesh which, once filled, are closed at their ends in the same packaging process.
This type of bags have the drawback that once they are formed, they do not have sufficient stiffness so as to be supported on their base due to the reticular structure of the mesh, adopting different shapes according to the packaged product.
Today, the packer needs for the product bags to have dimensions that are as uniform as possible and a sufficient stiffness for carrying out a good stacking and subsequent palletizing for the purpose of avoiding having to place the already made bags inside another stiff and stackable container, thus reducing transportation costs.
On the other hand, the existing bags are made up of two or even three different materials, and some of them are joined such that thy make it impossible to separate them for subsequent recycling since they incorporate sheets of plastic coated with materials different from the printed base for achieving a greater tensile strength.
In this sense, European patent number 0 047 544 discloses a solution for this type of bags consisting of providing the tubular band of mesh with two laterally opposite reinforcing flexible laminar bands susceptible to receiving graphic printouts, which bands are externally overlaid and joined at their ends to one another and to the mesh bag, and separated from the bag in the remaining areas.
The solution disclosed in said patent has the drawback that once the bag is filled, it lacks the consistency and strength necessary for being maintained upright since the flexible laminar reinforcements arranged externally do not affect the net mesh walls.
Another known solution is that disclosed in Spanish utility model number 200002993, consisting of a continuous laminar band closing on itself with the collaboration of a longitudinal welding line, which laminar band is constituted of three continuous strips of plastic alternated with woven mesh strips.
This solution has the drawback that the laminar band must be closed on itself prior to the moment of packaging and closing of the bag, therefore the process is equally complex. Furthermore, this solution involves an additional welding line to join the marginal strips of plastic, which hinders and makes the graphic printout thereof difficult, since three different types of bands with different printouts must be made.
Additionally, this solution uses woven mesh for forming the bag since the cost thereof is much more reduced. This represents another drawback due to the constitution thereof, since when it is cut to obtain the strips and to join them to the strips of plastic, it frays, and control over its structural position is lost.
On the other hand, the tests performed have shown that the joining of a plastic sheet to a woven mesh is weak, precisely due to the low structural density with which the woven mesh is formed.

DESCRIPTION OF THE INVENTION

The continuous sheath of mesh for forming bags for fruit and vegetable products and the like proposed by the invention solves the drawbacks set forth above since it is provided with at least one pair of longitudinal laminar bands of plastic susceptible to receiving a graphic printout, running along the length of the tubular wall, one band inside and the other one outside of said wall, in coinciding positions and joined to one another in order to fix between them the threads of the mesh strip situated between said bands.
The joining between the outer and inner bands is carried out by heat-welding or adhesive substances, such that their joining fixes the structure of the mesh strip situated between the bands.
Due to the technical features as well as to its reduced cost, the continuous tubular band is preferably of seamless woven mesh obtained by a circular knitting machine, or extruded mono-oriented mesh.
The continuous sheath of mesh of the invention is preferably formed from a single material, as it is not necessary to reinforce the side walls with other materials since the reinforcement occurs by trapping the structure of the mesh between the outer and inner plastic band.
Furthermore, the continuous sheath of mesh can be made with laminar bands of plastic of lesser thickness than those currently used, decreasing the amount of waste generated.
Recycling of the bag is thus facilitated since the amount of material is reduced, and a single material is used.

DESCRIPTION OF THE DRAWINGS

To complete the description being made and for the purpose of aiding to better understand the features of the invention, according to a preferred practical embodiment thereof, a set of drawings is attached as an integral part of said description in which, with an illustrative and non-limiting character, the following has been shown:
Figure 1 shows a perspective view of a span of the continuous sheath of mesh band for forming bags for fruit and vegetable products and the like, showing an exploded view of the longitudinal laminar bands of plastic.
Figure 2 shows a cross sectional view of a continuous sheath of mesh provided with a pair of longitudinal laminar bands of plastic.
Figure 3 shows a cross sectional view of a continuous sheath of mesh provided with two pairs of longitudinal laminar bands of plastic.
Figure 4 shows a cross sectional view of a continuous sheath of mesh provided with four pairs of longitudinal laminar bands of plastic.

PREFERRED EMBODIMENT OF THE INVENTION

In view of the mentioned figures, it can be observed how the continuous sheath of mesh for forming bags for fruit and vegetable products proposed by the invention is made up of a continuous tubular band (1) of mesh provided, in the basic example of figure 2, with a pair of longitudinal laminar bands running along the length of the walls of the tubular band (1) of mesh, one band (2a) inside and the other one (2b) outside, in coinciding position and joined to one another in order to fix between them the structure of the mesh strip situated between said laminar bands.
As can be seen in Figures 3 and 4, the continuous sheath can be provided with several pairs of laminar bands of plastic, according to the necessities, and with different widths, as in the specific case of Figure 4.
The laminar bands (2a and 2b) of plastic are joined to one another by means of heat-welding or adhesive substances, fixing between them the structure of the mesh strip situated between said bands.
Said laminar bands, preferably the outer band (2b), are susceptible to receiving graphic printout for containing all the information referring to the contained product, as well as the corresponding decorative motifs and commercial trademarks.
The inner laminar bands (2a) can be incorporated to the continuous sheath in the moment in which the tubular band of woven mesh is woven, adding the outer laminar bands (2b) already printed on at the output of the circular knitting machine. The joining of the pairs of laminar bands is subsequently carried out by means of heat-welding or adhesive substances, and it is finally wound for its distribution.
Regardless of whether the joining is carried out by heat-welding or by adhesive substances, this process neither deteriorates nor deforms the graphic printout of the outer band (2b), conserving its advertising and commercial appeal.
Seamless woven, tubular mesh obtained by a circular knitting machine or extruded mono-oriented tubular mesh will preferably be used for the composition of the continuous sheath of mesh.
Said materials have a very reduced economic cost due to their low structural density, and a high resistance in relation to their weight. However, they have the drawback that, precisely due to their low density, they are not suitable for being joined by heat-welding to a plastic band since said joining would be weak and unstable.
The use of woven tubular mesh or extruded mono-oriented tubular mesh for forming the continuous sheath of mesh proposed by the invention is completely suitable since it is neither joined nor welded directly to a laminar plastic band, but rather it is trapped between two laminar bands (2a and 2b) of plastic, therefore neither weakening nor breaking of the threads making up the structure occur.

Claims

A continuous sheath of mesh for forming bags for fruit and vegetable products and the like by means of transverse welding and cutting lines, characterized in that it is provided with at least one pair of longitudinal laminar bands of plastic running along the length of the tubular wall, one band inside and another one outside of said wall, in coinciding positions and joined to one another in order to fix between them the structure of the mesh strip situated between said bands.
A continuous sheath of mesh for fruit and vegetable products and the like according to claim 1, characterized in that the outer and inner bands are joined by means of heat-welding.
A continuous sheath of mesh for fruit and vegetable products and the like according to the previous claims, characterized in that the outer and inner bands are joined by means of adhesive substances.
A continuous sheath of mesh for fruit and vegetable products and the like according to claim 1, characterized in that the continuous tubular band is of seamless woven mesh obtained by means of a circular knitting machine.
A continuous sheath of mesh for fruit and vegetable products and the like according to claim 1, characterized in that the continuous tubular band is of an extruded mono-oriented mesh.