Bags made of open mesh material

OPEN MESH MATERIAL AND BAGS MADE OF THE SAME

CROSS REFERENCE WITH RELATED APPLICATIONS This Non-Provisional Application claims the benefit under 35 USC section 119 (e) of the following US Provisional Patent Applications, all of which are incorporated herein by reference in their entirety:

US Provisional Patent Application Series No. 61 / 250,299, filed on October 9, 2009, and entitled Open Mesh Nonwoven Fabric; US Provisional Patent Application Series No. 61 / 303,290, filed on February 10, 2010, and entitled Open Mesh Nonwoven Fabric; US Provisional Patent Application Series No. 61 / 305.003, filed on February 16, 2010, and entitled Multiple Substrate Bag and Method for its Production; and

US Provisional Patent Application Series No. 61 / 326.069, filed on April 20, 2010, and entitled Bag of Multiple Substrates and Method for Production.

BACKGROUND OF THE INVENTION

Field of the Invention

The invention relates to open mesh materials, and, more particularly, relates to an open mesh material formed from filaments, at least some of which are composite filaments that can be thermally bonded to other filaments in At least some intersection points. The invention further relates to various types of bags made from such material, and methods for obtaining those bags.

Description of Related Technique

Synthetic open mesh materials are used in a wide variety of applications, including bags, sediment fences and other barriers, bullet wrappers, and sieves. These materials are formed with an open mesh pattern. Traditional mesh materials took the form of crossed threads or filaments that were woven or knitted together without joining the filaments at their intersection points. More recently, cross-laminated synthetic films have been introduced, in which adjacent layers of divided and biaxially stretched sheets are fixed to each other through thermal bonding rather than through knitting or knitting. Many of the prior art open mesh materials lack dimensional stability. That is, they stretch relatively easily, so that, when used in applications such as bags, they expand or bulge undesirably under the weight of the items in the bag. These materials also tend to be relatively weak. Other materials offer better dimensional stability or strength, but are relatively heavy in terms of area. These prior art materials are also relatively expensive to manufacture. Its range of applications is also limited due to the limitations given the possible variations of the material properties.

SUMMARY OF THE INVENTION

<img file="CO6541549A2_D0001.tif" />

According to the first aspect of the invention, nn open mesh material includes filaments that intersect each other, at least some of the filaments being filaments of composite material having a support portion of a relatively high melting point, and a joining portion of a relatively low melting point, the joining portion of each filament of composite material being thermally bonded to other filaments at at least some intersection points. The open mesh material has a mass per unit area less than 30 g / m². In other embodiments, the open mesh material has a mass per unit area less than 25 g / m², less than 20 g / m², and even less than 15 g / m².

The open mesh material can be extended in the directions of the machine and transverse to the machine, and can have a mass resistance ratio in at least one of the directions of the machine and transverse to the machine of at least 2.67 N / (g / m²), in which the resistance is measured according to the ASTM D 5034 standard. In other embodiments, the mass resistance ratio may exceed 3.30 N / (g / m²), or even 4.45 N / (g / m²).

The open mesh material can have an elongation percentage in at least one of the machine directions and transverse to the machine of no more than about 50%, in which the elongation percentage is measured according to the ASTM D standard. 5034. In other embodiments, the elongation at break may be no more than 40%, or no more than 30%.

The open mesh material may have a mass per unit area less than 20 g / m², and a burst resistance of at least 80 kPa, in which the burst resistance is measured according to the ASTM D 3786 standard.

<img file="CO6541549A2_D0002.tif" />

Other embodiments, burst resistance can exceed 100 kPa, and even 150 kPa.

The open mesh material may have a tear strength at the intersection points of about 10 N, in which the tear strength is established in terms of the breaking strength of the material. In other embodiments, the tear strength can be more than 15 N, and even more than 20 N.

While the desired characteristics of the open mesh material in terms of weight per unit area, mass resistance ratio, elongation percentage, etc., may vary depending on the intended end use of the material, the material of the present description has a Low mass per unit area and a high mass resistance ratio, while maintaining good dimensional stability. This low mass per unit area and high material strength ratio reduce the carbon footprint associated with the manufacture, transport and disposal of products obtained from the material, such as bags for crop products, because the products They require less raw materials and take less volume. Therefore, they require less energy for their production and handling than products obtained from traditional materials.

In one configuration, the material is a nonwoven fabric that contains at least two layers of weft filaments that can be edged on one or both sides by a warp filament layer. The weft filaments cross each other at an acute angle to form a generally diamond-shaped pattern. The warp filaments extend at an acute angle with

<img file="CO6541549A2_D0003.tif" />

with respect to the filaments that intersect and parallel to each other, and can be extended in parallel with the machine direction. The warp filaments, and possibly also the weft filaments, are filaments of composite material that can be thermally bonded. Additional layers, such as additional warp and / or weft layers, a lanyard mechanism or other closure mechanism, a structure such as a tag, and / or one or more sheets may be provided on one or both surfaces of the fabric. of lamination or reinforcement. In a variant of this configuration, both layers of the filaments. Warp can be omitted, so that the tissue is formed from the weft filaments that intersect.

Many items can be obtained at least in part from these tissues, including sediment barriers, light barriers, and bags for containing crop products and other items. Such bags include bags with an L-shaped seam, bags of mol20 dear-fill-close (FFS), and bags of multiple substrates, such as HALF AND HALF® bags.

In the case of an L-shaped bag with seam, an open mesh material could be formed that had at least some of the characteristics described above, to include a closed end, an open end, at least one side seam in a side of it, and a seam at the closed end thereof. The side and end seams can be formed by sewing them to produce an L-shaped sewn bag. The open end may include a textured portion. The textured portion, if present, may include a band that is attached to the fabric, or a textured filament

<img file="CO6541549A2_D0004.tif" />

β zante arranged around the open end.

An L-shaped seam bag that has some or all of the characteristics of the L-shaped seam bag explained above can be sufficiently thin and understandable so that, when a plurality of the bags are stacked in a stack and subjected at a force of 267 kN, the stack contains at least 25 bags / cm. In other embodiments, the stack contains more than 30 bags / cm, and even more than 35 bags / cm.

Another aspect of the invention is based on a bag called molding, filling and closing. The bag according to this aspect has opposite sides first and second, each of which is formed at least in part from a tape of a sheet material, and at least in part from an open mesh material. The sheet material can be, for example, a film material obtained at least in part from thermoplastic film and extending longitudinally from at least one end of the bag. An end seam extends through one end of the bag and joins the first and second ribbons of the sheet material together with at least one layer of the open mesh material in between. The end seam is formed from a closure having a resistance of at least 2.5 N.

According to another aspect of the invention, a molding, filling and closing bag is provided having upper and lower ends, at least the lower end being closed. A body extends between the upper and lower ends to define an interior volume that contains items. The body of the full bag is at least generally polygonal in the form of a cross section along at least the majority of its length. The body has at least two opposite sides formed from an open mesh material that has a mass per unit area of ​​no more than 30 g / m². The bag has an initial height, measured from the lower end to the upper end, after the lower end is closed, and after the body is formed, but before the items are placed in the bag, and before closing the upper end The bag also has a final height that is measured after the items are placed in the bag and after the bag is placed on a horizontal surface and left without being held from the top. The final height of the bag is at least 35% of the initial height.

According to yet another aspect of the invention, there is provided a method for forming an end seam in a bag, such as a molding, filling and closing bag. The method comprises pressing opposite sides of the bag together under heat and pressure at a temperature less than 149 ° C and a residence time of less than 0.5 seconds, and producing a closure having a closure resistance of at least 2.5 N. The bag includes at least two layers of a sheet material, and at least one layer of an open mesh material placed between the layers of the sheet material. The seam can be formed from a flap closure.

According to yet another aspect of the invention, a bag of multiple substrates has a first side wall formed at least in part substantially from a tape of synthetic open mesh material, and a second side wall formed at least in part substantially from a sheet material. The opposite lateral edges of the first and second side walls are thermally bonded together in vertical seams, and a lower edge of the open mesh material tape is thermally bonded to the film material to form a lower horizontal seam. A reinforcing tape of a sheet material can be extended along an upper edge of the first side wall of the bag.

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The open mesh material can be extended in the directions of the machine and transverse to the machine, and can have a mass per unit area of ​​no more than 30 g / m², and a mass resistance ratio of at least 2.67 N / (g / m²) .

The increased mass resistance ratio and the resulting reduced mass of the bag also substantially reduce the carbon footprint of the multi-substrate bag. The multi-substrate bag is also relatively thin and compressible, allowing it to be stored and shipped in a given volume substantially more bags. In fact, the bag is sufficiently thin and understandable so that, when a plurality of the bags are stacked in a stack and subjected to a compressive force of 27.1 N, the stack contains at least 36.5 bags / cm.

The seam strength can be improved by configuring the mesh tape of the multi-substrate bag so that it has an increased surface area in the area of ​​overlap between the film tapes and the mesh tape. The increased surface area can be achieved by providing additional threads or filaments in the open mesh fabric at the seams, thereby increasing the surface area that is available for

<img file="CO6541549A2_D0005.tif" />

Union.

These and other features and advantages of the invention will be apparent to those skilled in the art from the following detailed description and the accompanying drawings. However, it should be understood that the detailed description and specific examples, although indicating preferred embodiments of the present invention, are given by way of illustration and not limitation. Many changes and modifications can be made within the scope of the present invention without departing from its spirit, and the invention includes all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings, in which similar reference numbers represent similar parts throughout, and in which:

FIG. 1 is a plan view of a section of an open mesh material constructed according to a first preferred embodiment of the invention;

FIG. 2 is a vertical section view taken generally along lines II-II in FIG. 1;

FIG. 3 is a side elevational view generally taken along lines III-III in FIG. 1;

FIG. 4 is a top plan view of an open mesh material constructed according to a second preferred embodiment of the invention;

FIG. 4A is a top plan view of an open mesh material that forms a variant of the material illustrated in FIG. 4;

FIG. 5 is a front sectional view of a

<img file="CO6541549A2_D0006.tif" />

filament used in the fabric of FIG. 4;

FIG. 6 is a detail view showing a portion of the tissue illustrated in FIG. 4;

FIG. 7 is a sectional view of the material, generally taken along lines VII-VII in FIG. 6;

FIG. 8 is a perspective view of a first bag made at least in part of an open mesh material;

FIG. 9 is a fragmented perspective view of a textured portion of the bag of FIG. 8;

FIG. 10 is a front view of an alternative embodiment of a textured portion suitable for use with the bag of FIG. 8;

FIG. 11 is a front view of an alternative embodiment of a textured portion suitable for use

<td colspan="3">with the bag of FIG.</td><td colspan="5"> 8;</td>

<td>the</td><td>FIG. 12 is</td><td>a</td><td>view</td><td>in perspective</td><td>from</td><td>a</td><td>rea-</td>

<td>lization</td><td>alternative</td><td>from</td><td colspan="2">a bag;</td><td></td><td></td><td></td>

<td>the</td><td>FIG. 13 is</td><td>a</td><td>view</td><td>in perspective</td><td>from</td><td>a</td><td>rea-</td>

<td>lization</td><td>alternative</td><td>from</td><td colspan="2">a bag;</td><td></td><td></td><td></td>

<td>the</td><td>FIG. 14 is</td><td>a</td><td>view</td><td>front of a</td><td colspan="3">realization</td>

alternative of a strand suitable for use with the bag of FIG. 13;

FIG. 15 is a front view of an alternative embodiment of a plurality of strands suitable for use with the bag of FIG. 13;

FIG. 16 is a perspective view of a bag of molding, filling and closing of multiple substrates obtained in part from an open mesh material; FIG. 17 is a front elevation view of the bag of FIG. 16;

<img file="CO6541549A2_D0007.tif" />

FIG. 18 is a right side elevation view of the bag of FIG. 16;

<td></td><td>FIG. 19 is</td><td>a</td><td>view</td><td>in</td><td>section from</td><td>the bag to-</td>

<td>mada</td><td>generally to</td><td>the</td><td>long</td><td>from</td><td>the lines</td><td>19-19 in the</td>

<td>FIG.</td><td> 17;</td><td></td><td></td><td></td><td></td><td></td>

<td></td><td>FIG. 20 is</td><td>a</td><td>view</td><td>in</td><td>section from</td><td>the bag to-</td>

<td>mada</td><td>generally to</td><td>the</td><td>long</td><td>from</td><td>the lines</td><td>20-20 in the</td>

<td>FIG.</td><td> 17;</td><td></td><td></td><td></td><td></td><td></td>

<td></td><td>FIG. 21 is</td><td>a</td><td>view</td><td>in</td><td>section from</td><td>the bag to-</td>

<td>mada</td><td>generally to</td><td>the</td><td>long</td><td>from</td><td>the lines</td><td>21-21 in the</td>

<td>FIG.</td><td> 18;</td><td></td><td></td><td></td><td></td><td></td>

<td></td><td>FIG. 22 is</td><td>a</td><td>view</td><td colspan="3">in side elevation in certain</td>

<td>mode</td><td>schematic of</td><td colspan="3">a machine</td><td>vertical</td><td>molding,</td>

filling and closing that can be used to obtain the bags of FIGS. 16-21;

FIG. 23 is a perspective view showing a portion of the vertical molding, filling and closing machine of FIG. 22 in greater detail;

FIG. 24 is a perspective view of a substrate that can be formed in the bag of FIGS. 1621 using the molding, filling and closing machine of FIGS. 22 and 23;

FIG. 25 is a perspective view of a molding, filling and closing bag constructed according to another embodiment of the present invention;

FIG. 26 is a perspective view of a substrate that can be converted into the bag of FIG. 25;

FIG. 27 is a side elevation view showing the bag of FIGS. 16-21 resting on a surface, adjacent to two bags filled with the prior art;

FIG. 28 is a perspective view of a bag

<img file="CO6541549A2_D0008.tif" />

of multiple substrates constructed according to another embodiment of the present invention;

<td></td><td>the</td><td>FIG. 29</td><td>is</td><td>a</td><td>view</td><td>in</td><td>raised</td><td>frontal</td><td>from</td><td>the</td>

<td>bag</td><td>from</td><td>FIG.</td><td> 28;</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td></td><td>the</td><td>FIG. 30</td><td>is</td><td>a</td><td>view</td><td>in</td><td>raised]</td><td>later</td><td>from</td><td>the</td>

<td>bag</td><td>from</td><td>FIG.</td><td> 28;</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td></td><td>the</td><td>FIG. 31</td><td>is</td><td>a</td><td>view</td><td>in</td><td>section</td><td>side</td><td colspan="2">taken</td>

generally along lines 31-31 in FIG. 28;

<td>FIG.</td><td>31A</td><td>is a</td><td>view</td><td>in lateral section</td><td>from</td><td>a</td>

<td>building</td><td colspan="2">alternative</td><td>of the</td><td>bag of FIGS.</td><td> 28-</td><td> 31;</td>

<td>FIG.</td><td>31B</td><td>is a</td><td>view</td><td>side elevation</td><td>from</td><td>other</td>

<td>building</td><td colspan="2">alternative</td><td>of the</td><td>bag of FIGS.</td><td> 28-</td><td> 31;</td>

<td>FIG.</td><td>31C</td><td>is a</td><td>view</td><td>side elevation</td><td>from</td><td>other</td>

<td>building</td><td colspan="2">alternative</td><td>of the</td><td>bag of FIGS.</td><td> 28-</td><td> 31;</td>

<td>FIG</td><td> . 32</td><td>is a</td><td>view</td><td>upstairs</td><td colspan="2">taken</td>

<td>usually</td><td>to what</td><td>long</td><td colspan="2">of lines 32-32 in</td><td>the</td><td>FIG.</td>

29;

FIG. 33 is a fragmented perspective view showing an upper portion of the bag of FIGS. 28-31;

FIG. 34 is a front fragmented elevation view of a portion of FIG. 29;

FIG. 35 is an exploded perspective view of the bag of FIGS. 28-31;

FIG. 36 is a rear elevational view of a bag constructed according to yet another embodiment of the invention;

FIG. 37 is a fragmented front elevation view of a portion of FIG. 36;

FIG. 38 is a front elevation view of a bag constructed according to yet another embodiment of the invention; and FIG. 39 is a fragmented front elevation view of a portion of FIG. 38.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Several non-limiting embodiments of an open mesh material will now be described, followed by a description of the applications of such material in the form of various bag styles.

1. Open Mesh Material

As indicated above, an open mesh material constructed in accordance with the present invention includes filaments that intersect each other and that thermally join at least some of their intersection points to form an open, dimensionally stable, strong, open mesh material of light weight. Possible materials include, but are not limited to, woven fabrics in which the filaments intersect as they intertwine with each other above and below, knitted fabrics in which the filaments intersect when intertwining them around each other, and non-woven fabrics. tissues in which the filaments intersect by stratifying them over each other crosswise. Intersecting, as used herein, means that the intersecting filaments are not parallel to each other and come into contact with each other in one or more locations. At least some of the filaments could come into contact and even be attached to other filaments without intersecting the other filaments. However, the filaments can also be contacted with other filaments without intersecting and / or without joining. For example, some of the filaments could intersect other filaments while being collinear with and rest on top of still other filaments, as is the case with the stacked warp filaments described below in conjunction with FIGS. 1-3. In that embodiment, the warp filaments of the upper layer intersect with the weft filaments while they are collinear with and rest on the upper part of the underlying warp filaments of the lower layer. In addition, at least some of the filaments could intersect each other without being thermally bonded together at their intersection points, as is the case with the weft filaments described below in conjunction with FIGS. 1-3.

The term filament, as used herein, means a strand of material, and should be considered synonymous with tape, band, thread, or strand. In order to provide a frame of reference, the expressions warp filaments and weft filaments will be used to describe the intersecting filaments. Typically, but not necessarily, the warp filaments will at least generally extend in the direction of the machine. It should be understood that these expressions are used merely as a frame of reference, and do not require that the material be obtained in any particular way or have any desired orientation unless otherwise specified. Other directional terms, such as above and below, are also used as a frame of reference and should not be construed as limiting.

Some or all filaments are composite filaments. The term "composite filament," as used herein, refers to a filament formed from a composite material having a support portion of

<img file="CO6541549A2_D0009.tif" />

high melting point, and a relatively low melting point joining portion. The support portion is also preferably, but not necessarily, of a density greater than the joint portion. It forms the structural component of the filament. These composite filaments can be formed from a variety of materials such as a monolayer material formed from a mixture of low melting and high melting materials. They can also be formed from stratified layers of material, or coextruded layers of material. Composite filaments formed from coextruded materials can be formed, for example, from a material called core and crust, in which a relatively high melting point core is surrounded by at least one layer of a crust of relatively low melting point. A single core can be provided within each crust. Alternatively, multiple cores can be encapsulated in each cortex. The encapsulated cores can be separated from one another or they can be in contact with each other, either side by side or being twisted or otherwise twisted together. Alternatively, the coextruded material could be formed from a relatively high melting point layer having a low melting point layer disposed on one or both sides of it. The term "melting point," as used herein, means the temperature at which the material can initiate bonding with another material.

Composite filaments could be formed (i) mixing materials in a monolayer or a monofilament, (ii) stratifying materials, or (iii) coextruding materials. To form these composite filaments, it is possible

<img file="CO6541549A2_D0010.tif" />

<img file="CO6541549A2_D0011.tif" />

They would use many permutations of low melting and high melting materials. Possible combinations of materials include a high density polyethylene (HDPE) or a medium density polyethylene (MDPE) as a support portion, and a low density polyethylene (LDPE) or a linear low density polyethylene (LLDPE) as a bonding material . These materials can be used alone or mixed, or otherwise combined with other materials. Other possible combinations of materials include the use of thermally sealable polypropylene as one or more of the support portion and the joint portions. In addition, other materials can be used for all or part of one or both portions (for example, biodegradable materials such as cellulose materials or starch materials). The material of the joint portion or portions has a lower melting point or initiates the union at a lower temperature than the material of the support portion or portions. The resulting composite filaments can be heated to a temperature at which the joint portion or portions bind or bind adjacent filaments sufficiently without appreciably affecting the dimensional and structural integrity of the support portion or portions.

Returning now to FIGS. 1-3, a first embodiment of an open mesh material formed from intersecting filaments of the type described above is illustrated. The material of this embodiment is a nonwoven fabric formed from two mutually intersecting groups of elongated weft filaments 1, 2 flanked by lower and upper warp layers 3 and 4, respectively. The warp layers 3 and 4 are formed from respective warp filaments 5 and 6,

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X

LU respectively. Wet weft filaments 1 and 2 cross each other at an acute angle to form a pattern with a generally diamond shape. The warp filaments 5 and 6 extend at an acute angle with respect to the intersecting filaments and parallel to each other. They extend in the direction of the machine in the illustrated embodiment, but could also extend in other directions.

In the present embodiment, weft filaments 1, 2 of the fabric are not composite filaments. As such, weft filaments 1, 2 are capable of joining together only to a relatively small degree, if they do so at all. The weft filaments 1, 2 are fixed in their mutual position with the help of lower and upper cover layers or warp layers 3, 4, each of which is formed by a plurality of spaced, parallel, elongated warp filaments 5 and 6, respectively. As shown in FIG. 1, the filaments 5 of the lower warp layer 3 and the filaments 6 of the upper warp layer 4 are placed in line with each other, so that the weft filaments 1, 2 are fixed between the tapes 5, 6 of the mutually connected layers without having to join the weft filaments 1, 2 with each other in the region of their crossing points. The layers are thermally bonded and pressed together after or during the laminate process, to fuse the layers together at their intersection points, thereby forming the tissue.

As mentioned above, the open mesh material of this embodiment is a nonwoven fabric formed from mutually crossed small filaments, each resting on their own planes, rather than taking the form of a knitted or woven fabric.

<img file="CO6541549A2_D0012.tif" />

in which the filaments are intertwined or forming loops with each other. As a result, simple construction conditions are obtained with the advantage that, in the crossover regions of the warp filaments and weft filaments, interlocking joints are not produced or forming loops that hinder the structural integrity of the tissue. At interlocking intersections or forming loops with each other, the filaments intersect each other so that the filaments change the planes. This change in the planes of the filaments in the interlocking or looped joints creates stress points in the knitted or knitted tissues. In the open mesh fabric of this embodiment, stress points are avoided because the warp and weft filaments simply rest flat on each and can be provided with a very small thickness of between 10 and 35 pm, for example , thus maximizing the full tensile strength of the fabric. The fixation of the mutual position of the weft filaments between the warp filaments ensures a heat sealable connection of the two warp layers to each other and of the warp layers to the interposed weft layers. The weft and warp filaments are thus slightly joined in a non-scrollable manner. The heat treatment of the fabric also ensures that the open mesh fabric is subjected to only a very low shrinkage and / or residual extensions.

To ensure that the warp filaments 3, 4 can positionally fix the weft filaments 1, 2 at the place of their intersection points via thermal bonding, the filaments of the warp layers 3, 4 are composite filaments, as explained previously. The

<img file="CO6541549A2_D0013.tif" />

Composite filaments can be formed from any combination of materials described above, as long as at least a portion of a melting point material larger than the other portions is formed. In the illustrated embodiment, the filaments 5 and 6 of the warp layers 3 and 4 are composite filaments formed from a coextruded film material having a support layer of a relatively high tensile strength and a high melting point, and a joining layer .10 of a relatively low melting point on at least the side of the support layer facing the weft filaments 1, 2. The support layer and the tie layer of the composite filaments of the warp layers 3 and 4 of this embodiment comprise an HDPE or an MDPE and a

LDPE or an LLDPE, respectively. The wet weft filaments of this embodiment are made of a relatively high strength material that has a melting point above that of the joining layer of the warp layer filaments. Currently preferred

HDPE, but other materials, such as thermally sealable polypropylene, can be used. The high density material of the weft filaments can be coated, although not necessarily, with a material of lower melting point, such as LLDPE, to enhance the junction at the points of intersection with the warp layer filaments.

The desired dimensions of the individual filaments can vary significantly depending on several factors, including the composition of the filaments and the intended use of the open mesh material. The warp and weft filaments may, for example, have a thickness of 40 to 200 micrometers, and more typically 60-150 micrometers. The weft filaments of the illustrated embodiment are considerably wider than the warp filaments, but filaments thereof or approximately the same widths could be used in all layers, if desired. In addition, weft filaments could be narrower than warp filaments.

Although the desired characteristics of the open mesh material in terms of mass per unit area, mass resistance ratio, elongation percentage, etc., may vary depending on the intended end use of the material, the material of the present invention has a low mass per unit area and a high mass resistance ratio, while maintaining good dimensional stability. This low mass per unit area and high material strength ratio reduce the carbon footprint associated with the manufacture, transport and disposal of products obtained from the material, such as bags for crop products, because the products They require less raw materials and take less volume. Therefore, they require less energy for their production and handling than products obtained from traditional materials.

An example is the application of the family or consumer bag, used to store items such as nuts, oranges, potatoes, onions, fish (such as prawns, mussels, or clams), newspapers, float bulbs, dried beans, and candies wrapped. These and other bags are used to store the items and present them at the point of sale. The open mesh material used to form at least part of these bags

<img file="CO6541549A2_D0014.tif" />

preferably has a mass per unit area less than 30 g / m², more preferably less than or equal to about 25 g / m², and even more preferably in the range of about 15 g / m² at about 20 g / m².

Its mass resistance ratio in at least one of the directions of the machine and transverse to the machine is preferably greater than or equal to about 2.67 N / (g / m²), more preferably greater than or equal to about 3.50 N / (g / m²), and even more preferably greater than or equal to about 4.45 N / (g / m²), in which the resistance is measured according to ASTM D 5034. As a measure of dimensional stability, the material preferably has an elongation percentage in at least one of the machine direction and the transverse direction of the machine equal to or less than 15 at about 50%, more preferably less than or equal to about 40%, and even more preferably less than or equal to about 30%, in which the elongation is measured according to ASTM D 5034.

An open mesh material, hereinafter material 1, which has been successfully tested in this regard is a nonwoven fabric formed from i) composite warp filaments each obtained from a 50 micrometer core layer of HDPE thickness coextruded on both upper and lower sides with a layer of

LLDPE 15 micrometers thick, and ii) weft filaments obtained from 100% HDPE. Using the test method of ASTM D 5034 to determine the breaking strength and elongation at break, the tissue was clamped between opposite tongs and stretched to its breaking point while measuring tissue elongation and applied force. The tissue is considered to break when it is pulled apart and subjected to

- 22 an applied force that reached a peak and then fell by at least 20%. The applied peak force was then recorded as the breaking force. The test was repeated both in the machine direction and in the cross machine direction for a statistically significant number of tissue samples. The trials revealed that the tissue had a mass per unit area of ​​20 g / m², a resistance of 92.6 N, and a weight resistance ratio of 4.63 N / (g / m²) in the machine direction. The fabric of material 1 also had a resistance of 41.8 N, and a mass resistance ratio of 2.09 N / (g / m²) in the transverse direction of the machine. It had an elongation percentage of around 42% in the machine direction, and about 33% in the machine transverse direction.

After the strands of the stratified structure of the nonwoven fabric of this embodiment are thermally bonded together, the resulting open mesh fabric is dimensionally stable, offers very low residual shrinkage and extension, and can be thermally bonded together with materials with similar melt index properties such as the same or similar fabrics, films, etc. The density of the fabric on a per area basis is determined by several factors, including the density and width of the individual filaments of each layer, the spacing between the parallel warp filaments 5 and 6 of each layer 3 and 4, and the step or the inclination of the weft filaments 1 and 2. The opening of the mesh increases with increasing the passage of the weft filament and / or increasing the spacing of the warp and / or weft filament. As the mesh opening increases, the density of the mesh decreases.

<img file="CO6541549A2_D0015.tif" />

lia. For filaments of a given composition and given dimensions, the dimensional stability and resistance of the fabric in the machine direction are at least generally proportional to the spacing between the warp filaments, and is generally proportional to the inclination or pitch of the filaments. frame in relation to the machine address. The dimensional stability and resistance of the fabric in the transverse direction of the machine, on the other hand, is generally proportional to the resistance of the joints at the intersection of the various layers, and inversely proportional to the inclination or passage of the weft filaments in relation to the machine address.

Returning now to FIGS. 4-7, a second embodiment of an open mesh material produced according to the description is illustrated. The material of this embodiment, like that of the first embodiment, is a nonwoven fabric formed from two mutually intersecting groups of weft filaments 11, 12 that are fixed in their mutual position as they are thermally bonded to layers lower and upper cover or warp layers 13, 14. Weft filaments 11 and 12 cross each other at an acute angle to produce a diamond-shaped pattern. Each warp layer 13 or 14 is formed from a plurality of spaced, parallel 15 or 16 filaments that extend in the direction of the machine. The filaments 15 and 16 of the warp layers are composite filaments as explained above in conjunction with the first embodiment.

The fabric of this embodiment differs from the fabric of the first embodiment in that weft filaments 11 and 12 are also composite filaments. All composite filaments 11, 12, 15 and 16 of the illustrated embodiment are obtained from the same composite material, but it will be understood that filaments 11 and 12 of the weft layers could be obtained from a composite material other than the filaments 15, 16 of one or both layers of warp 13, 14. The composite filaments illustrated are formed from a stratified coextruded material, but could be formed, for example, from mixed material, a laminated material, or a twisted or twisted material.

Each of the composite filaments illustrated 11, 12, 15, 16 of this embodiment comprises a three-layer coextruded material schematically illustrated in FIG. 5. That material has a central support layer 18, of relatively high melting point, and is flanked by upper and lower joining layers 19 and 21 of a relatively low melting point material. Layers 18, 19 and 21 can be formed from any combination of materials described above, in

<td>so much that</td><td>the support portion is formed of</td><td>a material</td><td>from</td>

<td>Point of</td><td>fusion greater than the portion</td><td>or portions</td><td>from</td>

<td>Union.</td><td></td><td></td><td></td>

<td>The</td><td>composite weft filaments</td><td colspan="2">11, 12 of this</td>

realization are positively attached to both warp filaments 15, 16 and each other at their intersection points. As a result of this configuration, the filaments of all tissue layers are joined together at all points of intersection by melting and re-hardening the material of the bonding layer, as schematically illustrated in FIG. 7. Since the resistance of the fabric in the transverse direction of the machine depends mainly on the added resistance

<img file="CO6541549A2_D0016.tif" />

of the joints, the positive union of weft filament to weft filament results in a resistance of the material in the transverse direction of the machine greater than that present in a material in which the weft filaments are not made from of a composite material (assuming that all other tissue characteristics, including filament thickness, filament density, filament composition, etc., are the same).

A material, hereinafter referred to as material 2, which has been successfully tested in this regard has filaments composed of both warp and weft formed from a central HDPE layer 50 micrometers thick coextruded on both upper and lower sides with a 15 micrometer thick LLDPE layer. Material 2 had a mass per unit area of ​​20 g / m². It had a resistance of 89.8 N, and a mass resistance ratio of 4.49 N / (g / m²) in the machine direction. Material 2 also had a resistance of 59.6 N, and a mass resistance ratio of 2.98 N / (g / m²) in the transverse direction of the machine. It had an elongation percentage of around 40% in the machine direction, and about 27% in the machine transverse direction.

The fabric illustrated in FIGS. 4-7 also differs from the tissue illustrated in FIGS. 1-3 because the filaments of the lower warp layer 15 are offset from the filaments of the upper warp layer

16. This arrangement provides more points of intersection in a given area of ​​tissue for bonding, although with less material that is available for bonding at any given point of intersection. Of course, the filaI

The lower warp merits 15 could also be aligned with the upper warp filaments 16 as explained above in relation to the first embodiment.

At least some of the warp filaments in one and possibly both layers 13 and 14 could extend nonlinearly rather than linearly. An example of this alternative is illustrated in FIG. 4A, in which some of the filaments 16 'in the upper warp layer 13 are arranged in a generally sinusoidal waveform. Other repetitive or non-repetitive waveforms are also possible. For example, one of the filaments 16 is shown as a sinusoidal wave form that is displaced 180 degrees relative to that of an adjacent non-linear filament 16 '. These and other variants could be provided in the same tissues or in different tissues.

Many changes and modifications could be made to the open mesh materials described herein without separating from the spirit of the present description. For example, as mentioned briefly above, one or both layers of warp of the nonwoven fabric of FIGS could be omitted. 1-3 or nonwoven fabric of FIGS. 4-7, producing a two or three layer fabric. In addition, one or more auxiliary materials or layers can be provided outside and / or within one or both warp layers, or even in the weft layer. For example, on a surface of one or both warp layers, a structure such as a tag, one or more lamination or reinforcement sheets, or one or more additional warp layers could be provided. A closure device, such as a cord, could also be provided in the weft layers.

<img file="CO6541549A2_D0017.tif" />

In addition, although the discussion focuses primarily on nonwoven fabrics, the description also applies to knitted or knitted fabrics in which at least some of the filaments that intersect with each other thermally join together at least some of their points. of intersection Open mesh materials that fall within the scope of this description will hereinafter be referred to as ultra-mesh materials as a short designation for those materials.

Characteristics of Open Mesh Material

Specific examples of open mesh materials of the type described above were tested. Four samples were tested, grouped according to the following:

Sample 1: An ultra-mesh material formed from a nonwoven fabric of the type generally illustrated in FIGS. 4 and 5-7 above. The fabric consisted of two layers of warp of a coextruded filament flanking two layers of high density polyethylene (HDPE) weft. The weft filaments extend at angles included at about 30 ° in relation to the transverse direction of the machine (a is shown in FIGS. 34, 37 and 39 below). Each individual filament thus extended at an angle of 15 ° in relation to the transverse direction of the machine.

til

Each weft filament was formed from a strip of three micrometer thick layers, which has a 50 micrometer thick HDPE layer interposed between two micrometer thick layers of a LLDPE linear low density polyethylene. The strip was stretched in a 6: 1 ratio to form the filaments that were incorporated into the tissue, after which the composite filament had a thickness of about 0.03 mm and a width of about 1.2 mm. The warp filaments of each layer were separated 8 mm. The fabric was an alternate fabric in which the warp filaments of the lower layer were separated about halfway between the warp filaments of the upper layer, leading to a spacing of the warp filament in the fabric of about 4 mm. Each filament of the weft layer had a thickness of about

0.04 mm, and a width of about 1.5 mm.

Sample 2: An ultramalla material that is the same as Sample 1, except for the fact that the weft filaments had an included angle of about 36 ° in relation to the transverse direction of the machine.

<img file="CO6541549A2_D0018.tif" />

- 29 Sample 3: An ultra-mesh material that is the same as Sample 1, except for the fact that the weft filaments had an included angle of about 40 ° in relation to the transverse direction of the machine.

Sample 4: An ultramalla material that is the same as Sample 1, except for the fact that the weft filaments had an included angle of about 4 6 ° in relation to the transverse direction of the machine.

The test results are summarized in Table 1 below:

TABLE 1: CHARACTERISTICS OF THE OPEN MESH MATERIAL

<td>Characteristic</td><td colspan="4">Sample No.</td>

<td></td><td> 1</td><td> 2</td><td> 3</td><td> 4</td>

<td>Mass (g / m²)</td><td> 20</td><td> 19</td><td> 18</td><td> 17</td>

<td>Breaking Strength (Machine Address - N) (ASTM D 5034)</td><td> 85</td><td> 83</td><td> 63</td><td> 68</td>

<td>Mass Resistance Ratio (Machine Address - N / (g / m²) )</td><td> 4,25</td><td> 4,37</td><td> 3, 50</td><td> 4,00</td>

<td>Breaking Strength (Transversal Directorate of the Machine - N) (ASTM D 5034, Grab Method)</td><td> 87</td><td> 41</td><td> 69</td><td> 52</td>

<img file="CO6541549A2_D0019.tif" />

<td>Mass Resistance Ratio (Transversal Directorate of the Machine - N / (g / m²) )</td><td> 4,35</td><td> 2,15</td><td> 3,83</td><td> 3,06</td>

<td>Burst Resistance (kPa) (ASTM D 3786)</td><td> 200</td><td> 172</td><td> 131</td><td> 96</td>

<td>Rupture Elongation (Machine Address -%) (ASTM D 5034)</td><td> 51,0</td><td> 51,8</td><td> 57,1</td><td> 57,1</td>

<td>Rupture Elongation (Transversal Directorate of the Machine -%) (ASTM D 5034)</td><td> 28,6</td><td> 17,5</td><td> 31,7</td><td> 32,7</td>

<td>Static Friction Coefficient (Machine Address - ASTM D 1894)</td><td> 0,562</td><td> 0,366</td><td> 0,317</td><td> 0,478</td>

<td>Kinetic Friction Coefficient (Machine Address - ASTM D 1894)</td><td> 0, 689</td><td> 0, 647</td><td> 0,860</td><td> 0,555</td>

<td>Static Friction Coefficient (Transversal Directorate of the Machine - ASTM D 1894)</td><td> 1, 300</td><td> 1,130</td><td> 1,390</td><td> 1,220</td>

<td>Kinetic Friction Coefficient (Transversal Directorate of the Machine - ASTM D 1894)</td><td> 1,150</td><td> 1,200</td><td> 1,160</td><td> 1,030</td>

<img file="CO6541549A2_D0020.tif" />

The friction coefficient tests were carried out according to the ASTM D 1894 ASTM standard. The friction coefficients were measured by sliding a sled, which has its bottom surface coated with a spongy rubber, on a flat surface that supports the material to be tested. .

An ultra-mesh material was also tested to determine the stackability. Stackability, as used herein, refers to the number of material belts that are contained in a stack of a given height when that stack is subjected to a given force. The stacking could be linear, stacking the tapes separated one over the other as would typically be the case when the items are stored in a box or other container. Alternatively, the stack could be tubular, as would typically be the case when a material is wrapped around itself to form a roll. It could also be linear, but formed from a continuous sheet folded in a pattern called Z-folding. Stackability is an important characteristic for many materials because, among other reasons, the materials or products obtained at least in part from They must be transported and stored. All else being equal, it is desirable to contain more materials or products in a stack of a given depth, to increase the number of materials or products that can be transported and stored in a given volume, thereby reducing storage space and further reducing the carbon footprint of the materials or products in terms of their transport costs.

For this test, 250 tapes of an ultramalla material were placed in a stack, and the initial height of that stack was measured. The ultrama11a material was of a type that is very suitable for use in bags and which was subjected to many of the tests cited here. It will be referred to here as the ultramalla material A for the sake of conciseness. The ultra-mesh material A is a nonwoven fabric of the type generally illustrated in FIGS. 1-3. The tissue had a density of 20 g / m², and consisted of two layers of warp of a coextruded filament flanking two layers of high density polyethylene (HDPE) weft. The warp filaments extend in parallel with the machine direction. The weft filaments extend at an included angle of about 36 ° in relation to the transverse direction of the machine. Each weft filament is formed from a three-layer strip of 80 micrometers thick having a 50 micrometer thick HDPE layer interposed between two 15 micrometer thick layers of a LLDPE linear low density polyethylene. This strip was stretched at a 6: 1 ratio to form the filaments that were incorporated into the tissue, after which the composite filament had a thickness of about 0.03 mm and a width of about 1.2 mm. The warp filaments of each layer are separated 8 mm. Each filament of the weft layer has a thickness of about 0.02 mm, and a width of about 1.5 mm.

A force of 27.1 N was then applied to each stack evenly along the length of the stack, and the height was again measured. The 27.1 N force was designed to emulate the compressive force typically imposed on article stacks when placed in boxes. A total force of 42.3 N was then uniformly applied along the length of each stacking isa, and the height was again measured. The results of these tests are summarized in Table 2 below.

TABLE 2: AI APILABILITY TEST RESULTS

ULTRAMALLA

<td>Height Precom-</td><td>Number</td><td>Height compressed</td><td>Number</td><td>Height Compressed</td><td>Number</td>

<td>primacy</td><td>from Cin-</td><td>@ 27.1 N</td><td>from Cin-</td><td>@ 42.3 N</td><td>of fifty</td>

<td>(dog)</td><td>tas / cm</td><td>(cm)</td><td>tas / cm</td><td>(cm)</td><td>tas / cm</td>

<td> 3,59</td><td> 61,3</td><td> 1,43</td><td> 174,8</td><td> 1,27</td><td> 196, 9</td>

Another significant characteristic of the materials formed by intersecting filaments or other intersecting structures is the resistance imparted to the material by the junctions at the intersection points. Bond strength tests were carried out to measure the tensile or tear resistance of the ultramalla material A at the points of intersection, and to compare the observed resistance with the resistances between the joined cross-laminated layers of a cut film and stretched that forms a fabric that is marketed under the trade name CLAF®. CLAF® is a registered trademark of ENOS ANCI, Inc. Three materials were tested, namely:

• CLAF® grade MS, • CLAF® grade S, and • ultra-mesh A as described above.

In each test, a rectangular tape of the material to be tested was prepared, 5.1 cm wide and 20.3 cm long, extending the portion of the sample perpendicular to the machine in the longitudinal direction of the sample, and moving the portion of the machine in the width direction. The samples tested of the ultra-mesh material A thus had their warp filaments extending in the direction of the width of the sample. Each sample to be tested was placed between two vertically separated pliers. The upper end of the tape to be tested was attached to the upper pliers by hooking the warp structure onto six evenly spaced hooks that extended downward from the upper pliers and that were hooked on a horizontally extending portion of the material. In the case of the ultramalla material A, the hooks hooked one of the warp filaments. The lower end of the tape was fastened to the lower pliers, making sure that the material was fixed both in the upper hook system and in the lower pliers while maintaining a vertical alignment of the tape with the upper and lower pliers. The tongs were then separated by pulling them at the speed of 30.5 cm / min. while measuring the force imposed on the sample. The breaking force or peak force imposed on the sample, calculated as described above in conjunction with the discussion of material 1, was recorded as a measure of the tear strength at the intersection points, or simply the bond strength. The test was repeated for a series of 10 samples of each of the materials tested. The breaking force and the standard deviation were then recorded for each material as reflected by Table 3 below.

TABLE 3: STRENGTH RESISTANCE AT INTERSECTION POINTS

<td>Mesh Type</td><td>Average Breaking Force (N)</td><td>Breaking Force Standard Deviation%</td>

<td>CLAF® grade MS</td><td> 9, 6</td><td> 0,28</td>

<td>CLAF® grade S</td><td> 9,6</td><td> 0, 44</td>

<td>Ultramalla A</td><td> 25,1</td><td> 1,35</td>

Table 3 confirms that, on average, the ultra-mesh material A has a tensile or tear resistance at the intersection points of the warp and mesh filaments, as measured by the breaking strength of the material, around 10 N, about 15 N, and even about 20 N. The resulting tear resistance is perfectly about twice that exhibited by the tested CLAF® materials, despite the fact that the ultramalla material A is lighter and more open than the CLAF® materials. It is believed that comparable results would be obtained with the other ultramalla materials described herein.

The specific ultramalla materials described above, including material 1, material 2, and ultramalla A, as well as many other fabrics and other open mesh materials that fall within the scope of the present description, could be converted into any one of a wide variety of items, such as bags, sediment fences, bullet wrappers, or sieves, through any of several conversion operations. This conversion could be carried out for-

<img file="CO6541549A2_D0021.tif" />

control seams by applying heat, folding, sewing, by using adhesives, or any combination thereof. Now three such applications will be described.

two. Seam-shaped Bags

Open mesh materials according to the present description, and also referred to as ultra-mesh materials for the sake of conciseness, can be converted into a so-called L-shaped seam bag by folding the material around itself to provide an edge seam vertical, and sewing the fabric to its lateral and inferior edges. The resulting bag would have an open upper part, an edge formed from a folding, and a second edge and a lower part formed from seams. These seams are typically formed by sewing, but could possibly be formed by thermal bonding, using adhesives, or by some combination of any or all of these three and possibly other techniques. The warp layers in the fabric would preferably extend horizontally along the bag to maximize the strength of the side seam.

Referring now to FIG. 8, an L-shaped sewing bag 20 includes a first end 22 and a second end 24 disposed opposite. The bag 20 further includes a side seam 26 that extends between the first and second ends 22, 24. The bag is formed from an open mesh material, preferably one of the non-woven fabrics described above, or a fabric or other Open mesh material that has similar characteristics.

κι

In the orientation shown in FIG. 8, the first end 22 of the bag 20 is an end of the bottom, while the second end 24 of the bag 20 is an end of the top. The end 22 of the lower part is a closed end, while the end 24 of the upper part is an open end. However, the upper end could be closed after being filled using any suitable technique.

In one embodiment shown, the bag 20 is formed by folding (i.e., bending over itself) the material and sewing the material at its side and bottom edges so that the bag 20 includes an inner cavity 28. The bags having side seams and lower sewn are usually referred to as sewn bags in the form of L.

The side seam 26 of the bag 20 of this embodiment is formed by sewing opposite sides of the material together after the material has been folded. One side 30 that is opposite the side seam 26 is a folding or bending, which is formed by folding the material on itself. The lower end 22 includes a seam 32 that is formed by sewing a first portion of an edge of the material to an overlapping portion of the edge after the material has been folded.

In the embodiment shown, the material of the bag 20 is a nonwoven fabric oriented such that the warp filaments 15, 16 (FIGS. 1-3) are generally parallel to the seam 32 of the lower end 22 of the bag 20. In the orientation shown, the warp filaments 15, 16 extend horizontally along the bag 20 to maximize resistance.

<img file="CO6541549A2_D0022.tif" />

side seam 26.

Referring now to FIGS. 8 and 9, the upper end 24 of the bag 20 will be described. The upper end 24 includes an edge 34. The edge 34 defines an opening 36 that provides access to the inner cavity 28.

The upper end 24 further includes a textured portion 38 disposed adjacent to the edge 34. The textured portion 38 is adapted to provide a texture that is distinct from the texture of the fabric of the bag 20. This distinctive texture of the textured portion 38 of the bag 20 allows handlers to identify the upper end 24 of bag 20 by feeling or touch.

The textured portion 38 includes a filament 40. In one embodiment, the filament 40 has an outer diameter that is in a range of about 0.1 mm to about 1 mm. In another embodiment, the outer diameter of the filament 40 is in a range of about 0.1 mm to about 0.5 mm. In another embodiment, the outer diameter of the filament 40 is in a range of about 0.2 mm to about 0.3 mm. In the depicted embodiment of FIGS. 8 and 9, the textured portion 38 includes a plurality of filaments 40. The filament 40 is placed on an outer surface of the fabric of the bag 20 adjacent to the edge 34 of the upper end 24. In the embodiment shown, the filament 40 is placed on the outer surface of the fabric of the bag 20, so that the filament 40 is not twisted or intertwined with the tissue. The filament 40 extends continuously around the upper end 34 of the bag 20.

<img file="CO6541549A2_D0023.tif" />

In the depicted embodiment of FIGS. 8 and 9, the filament 40 is oriented such that it is generally parallel to the warp filaments 15, 16 of the fabric of the bag 20. In another embodiment, the filament 40 is generally horizontal in the bag 20. In another embodiment, the Filament 40 is generally parallel to a plane in which the opening 36 of the upper end 24 is placed.

In one embodiment, the filament 40 is a monofilament that is made of a high density polyethylene (HDPE) material. In another embodiment, the filament 40 is a coextruded filament having a support portion and a joint portion. The support portion can be made from materials that include a high density polyethylene (HDPE) or a medium density polyethylene (MDPE), while the joint portion can be manufactured from materials that include a low density polyethylene. (LDPE) or a linear low density polyethylene (LLDPE).

In one embodiment, the textured portion 38 includes a band 42 that extends around the upper end 24 of the bag 20 at a location that is adjacent to the edge 34 of the upper end 24. The band 42 is a narrow ribbon of material. The band 42 can be manufactured from a thermoplastic material that includes polypropylene, low density polyethylene, coated polyester, etc. In one embodiment, the material of the band 42 has a thickness of about 25 micrometers. In one embodiment, the thermoplastic material of the band 42 is transparent or translucent. In another embodiment, the thermoplastic material of the band 42 is opaque.

The band 42 defines a width W. In one embodiment, the width of the band 42 is less than or equal to about 50.8 mm. In another embodiment, the width W of the band 42 is less than or equal to about 38.1 mm. In another embodiment, the width W is less than or equal to about 25.4 mm.

In another embodiment, the band 42 is used without the filament 40. In this embodiment, the inner surface 46 of the band 42 is attached to warp layers 14 and weft filaments 11, 12.

The band 42 includes an external surface 44 and an internal surface 46 disposed opposite. In the depicted embodiment of FIGS. 8 and 9, the inner surface 46 joins warp layers 14, weft filaments 11, 12, and filament 40. In one embodiment, the inner surface 46 of the band 42 includes a joint portion that is adapted to adhere to the warp layers 14, weft filaments 11, 12 and filament 40 by applying heat and pressure.

Referring now to FIG. 10, an alternative embodiment of a textured portion 138 of the bag 20 is shown. The textured portion 138 includes the band 42 and a filament 140, which is placed adjacent the edge 34 of the upper end 24 of the bag 20. In the present embodiment, the filament 140 is placed on an outer surface of one of the warp filaments 16 of the warp layer 14, so that a portion of the filament 140 is disposed between the warp filament 16 and the band 42.

The filament 140 is arranged in a non-linear waveform pattern (eg, square, triangular, sawtooth, sine, etc.). The latory waveform pattern 41 of filament 140 is a generally oscillating pattern. The oscillating pattern of filament 140 defines a plurality of peaks 148a, and a plurality of valleys 148b. In the embodiment shown, the oscillating pattern is generally sinusoidal.

Referring now to FIG. 11, an alternative embodiment of a textured portion 238 of the bag 20 is shown. The textured portion 238 of the bag 20 includes a plurality of filaments 240. The plurality of filaments includes a first filament 240a and a second filament 240b. The first filament 240a is disposed in a first non-linear waveform pattern, while the second filament 240b is disposed in a second nonlinear waveform pattern. In the embodiment shown, the first and second waveform patterns are generally sinusoidal. The second waveform pattern is out of phase with respect to the first waveform pattern. For example, in the embodiment shown, the first and second waveform patterns are 180 ° out of phase.

Referring again to FIG. 8, the bag 20 includes a tag 50. The tag 50 extends around at least a portion of the bag 20. In the embodiment shown, the tag 50 is placed between the lower and upper ends 22, 24 of the bag 20.

The label 50 includes an external surface 52 and an internal surface disposed opposite. The outer surface 52 is adapted to include distinctive marks (for example colors, numbers, letters, symbols, etc.) regarding information (for example, manufacturer, weight, ingredients, dates, nutritional information, etc.) on the contents placed in the inter cavity

<img file="CO6541549A2_D0024.tif" />

ior 28 of bag 20.

The internal surface of the label 50 may be a surface free of adhesives. It will be understood that the expression free of adhesives means that the inner surface does not include an applied adhesive or an adhesive coating. The internal surface of the tag 50 is fixed to the composite filaments of the fabric of the bag 20 by the application of heat and pressure. In one embodiment, the inner surface of the tag 50 is fixed to the warp layers 14 of the bag 20. In another embodiment, the inner surface of the tag 50 is fixed to the warp and weft layers of the bag 20.

Referring now to FIG. 12, an alternative embodiment of a bag 320 is shown, which is constructed from an open mesh material of the present description. The bag 320 includes a lower end 322, an upper end 324 disposed opposite, and a side seam 326 extending between the lower and upper ends 322, 324.

The lower end 322 is a closed end, while the upper end 324 is open. The upper end 324 defines an opening 336 that provides access to an inner cavity 328 of the bag 320.

The bag 320 of this embodiment further includes a closure element 360. The closure element 360 is adapted to selectively close the opening 336 to prevent or block access to the inner cavity 328 of the bag 320. In one embodiment, the element of 360 closure is a warp knitted fabric. In another embodiment, the closure element 360 is a nonwoven fabric. The closure element 360 can be manufactured from a thermoplastic material such as polyethylene, polypropylene.

<img file="CO6541549A2_D0025.tif" />

Pylene, high density polyethylene, nylon, polyesters, etc.

The closure element 360 is disposed at the upper end 324 of the bag 320. The closure element 360 is freely disposed between the weft filaments 11, 12-, so that the weft filaments 11, 12 can slide along length of the closure element 360. In the embodiment shown, the closure element 360 is disposed between the weft filaments 11, 12 so that the closure element 360 is generally parallel to the warp filaments 16 of the bag 320. Although the closure element 360 is captured between the weft filaments 11, 12, the closure element 360 is secured to the bag 320 in the side seam 326.

To close the opening 336 of the upper end 324, the closure element 360 is pulled in a direction that is generally out of the upper end 324. As the closure element 360 is pulled, the weft filaments 11, 12 slide along the closure element 360 towards other weft filaments 11, 12 of the fabric of the bag 320, and are joined. As the weft filaments 11, 12 slide along the closure element 360, the size of the opening 336 is reduced. When the weft filaments 11, 12 are joined together, the closure element 360 can be held to secure the upper end 324 in a closed position (that is, when the opening 336 is closed).

Referring now to FIG. 13, an alternative embodiment of a bag 520 is shown, which is constructed from the fabric of the present description. The bag 520 includes a lower end 522, an upper end 524 arranged opposite, and a side seam 526 extending between the lower and upper ends 522, 524.

The lower end 522 is a closed end, while the upper end 524 is an open end. The lower end 522 includes a seam 532 that is formed by sewing a first portion of an edge of the fabric to an overlapping portion of the edge after the fabric has been folded. The upper end 524 defines an opening 536 that provides access to an inner cavity 528 of the bag 520.

The bag 520 includes a plurality of threads 570. The plurality of threads 570 is adapted to increase the strength of the rings of the bag 520 without significantly increasing the weight of the bag 520.

The plurality of strands 570 are arranged in the bag 520 so that the strands 570 are generally parallel to the warp filaments 16 of the fabric. In one embodiment, the strands 570 are arranged adjacent to the warp filaments 16. In another embodiment, the strands 570 are disposed between adjacent warp filaments 16. In another embodiment, the threads 570 are arranged on the warp filaments 16. In one embodiment, each of the threads 570 has a terminal portion 572 that is securely fixed in the side seam 526 of the bag 520.

The strands 570 have a tensile strength that is greater than or equal to the tensile strength of the warp filaments 16. The strands 570 can be made of various materials. In one embodiment, each of the threads 57 0 is a nonwoven or thermoplastic material, such as a polyester material. In another embodiment, each of the threads 570 can be obtained az

/ 41 from the thread used to securely fix the side seam 526 and seam 532 at the lower end 522.

The threads 570 are arranged at intervals along an axial distance D of the bag 520. In one embodiment, the intervals between the threads 570 are fixed (ie, the intervals between the threads 570 are equal). In another embodiment, the intervals between the threads 570 may vary, so that the intervals between threads are uneven.

In one embodiment, the axial distance D at which the threads 570 are placed is equal to the length L (ie, from the lower end 522 to the upper end 524) of the bag 520. In another embodiment, the threads 570 can be locate along the length L, depending on the particular application for the bag 520, such that the axial distance D is less than the length L of the bag 520. In one embodiment, the threads 570 are arranged in the lower half of the bag 520, so that the axial distance D is less than or equal to 0.5 L as measured from the lower end 522 of the bag 520. In another embodiment , the threads 570 are arranged in a lower third of the bag 520, so that the axial distance D is less than or equal to 0.33 L as measured from the lower end 522 of the bag 520. In another embodiment, the threads 570 are arranged in the lower quarter of the bag 520, so that the axial distance D is less than or equal to 0.25 L as measured from the lower end 522 of the bag 520.

Referring now to FIGS. 14 and 15, an alternative embodiment of the threads 570 for the bag 520 is shown. In this alternative embodiment, the

Vo strand 570 is arranged on the warp filament 16 so that the strand 570 forms a waveform pattern (eg, square, triangular, sawtooth, sinusoid, etc.). In the depicted embodiment of FIG. 14, the waveform pattern has a generally sinusoidal shape.

In the depicted embodiment of FIG. 15, a plurality of strands 570 are disposed on each warp filament 16. The plurality of strands 570 includes a first strand 570a and a second strand 570b. The first strand 570a is arranged in a first waveform pattern, while the second strand 570b is arranged in a second waveform pattern. In the embodiment shown, the first and second waveform patterns are generally sinusoidal. The second waveform pattern is out of phase with respect to the first waveform pattern. For example, in the embodiment shown, the first and second waveform patterns are 180 ° out of phase.

Being formed from an ultra-mesh material, the L-shaped stitched bag constructed according to the present description, referred to herein as a new-style L-shaped stitched bag for the sake of conciseness, shows superior stackability when it is compared with the L-shaped sewn bags of the prior art. Traditionally, L-shaped sewn bags have been transported and stored in bullets, in which several thousand bags are compressed and joined together using a tying and / or shrink wrap. Each bullet typically contains four or five stacks of bags of equal numbers arranged close to each other. The united bullets are then stacked in

<img file="CO6541549A2_D0026.tif" />

<img file="CO6541549A2_D0027.tif" />

a pallet and compressed to a final height, typically around 50 inches (127 cm), and the entire pallet is wrapped by shrinkage. Then several pallets are placed in a truck for transport.

The stackability of the new-style L-shaped stitched bags, made from the ultramalla A material described above, was tested against traditional L-shaped stitched raschel bags using this pallet packing and stacking process . Two sizes of each bag style were tested: a 10-pound bag and a 5-pound bag. It should be noted at this time that bag sizes are often cited in the packaging industry as a function of their volumetric capacity or based on intended weight. Therefore, a 10-pound bag is one that is designed to have a working capacity of 10 pounds (4.5 kg), a 5-pound bag is one that is intended to have a working capacity of 5 pounds (2 , 7 kg), etc.

The bags were packed using a force of 60,000 pounds (267 kN) and stacked on pallets using the technique described above. The test results are summarized in Table 4 below:

<img file="CO6541549A2_D0028.tif" />

TABLE 4: APILABILITY OF BAGS WITH SEEDS IN FORM

OF THE

<td></td><td>Raschel 10 pounds</td><td>Ultra mesh 10 pounds</td><td>Raschel 5 pounds</td><td>Ultra mesh 5 pounds</td>

<td>Size of the Bag</td><td>10 pounds</td><td>10 pounds</td><td>5 pounds</td><td>5 pounds</td>

<td>Number of bowl- sas / stacking to</td><td> 750</td><td> 1.000</td><td> 600</td><td> 1.000</td>

<td>Number of Bags / Bullet</td><td> 3.000</td><td> 4.000</td><td> 3.000</td><td> 5.000</td>

<td>Dimension of the Bullet (cm)</td><td>52, 1 x 116.8 x 35, 6</td><td>52.1 X 116.8 x 22.9</td><td>58.4 x 114.3 x 33.7</td><td>53.3 x 116.8 x 25.4</td>

<td>Height of the Bullet (cm)</td><td> 35, 6</td><td> 22, 9</td><td> 33, 7</td><td> 25,4</td>

<td>Bags / cm</td><td> 21,1</td><td> 43,7</td><td> 17,8</td><td> 39, 4</td>

<td>Fi- Number the / Stacking to</td><td> 4</td><td> 6</td><td> 5</td><td> 6</td>

<td>Number of Ba- the / pallet</td><td> 8</td><td> 12</td><td> 10</td><td> 12</td>

<td>Number of Bags / Pallet</td><td> 24.000</td><td> 48.000</td><td> 30.000</td><td> 60.000</td>

The improvements are significant.

As can be seen from Table 4 above, 3,000 pockets with L-shaped knitted raschel seams of 10 pounds up to a height of 14 inches (35.6 cm) were compressed during the packing process, resulting in the formation of a stacking of 43.7 bol49 sas / cm when the stacked bags were subjected to a force of 267 kN. Therefore, each bullet contained 3,000 bags. Comparatively, 4,000 bags of L-shaped ultra-mesh seam of 10 pounds of new style were compressed to a height of 9 inches (22.3 cm) during the packing process, resulting in the formation of a 21.1 stack bags / cm when the stacked bags were subjected to a force of 267 kN. These results confirm that by subjecting the stacks of bags with L-shaped seams constructed in accordance with the present description to a force of 267 kN, a stack is formed having more than 25 bags / cm, more than 30 bags / cm, and even more than 35 bags / cm.

Due to the reduced bullet height of the new-style mesh bags compared to a bullet of stitched L-shaped raschel bags, it was possible to store more bullets in a pallet. For transport and storage purposes, the maximum desired height of a pallet and the items stored therein are typically considered to be around 50 inches (127 cm). The 10 lb raschel knitted L-shaped stitched bag bullets are typically stacked on a four-layer pallet, each containing two bullets. Due to the reduced bullet height of the 10-pound L-shaped seam bags made of ultramalla material A, two additional rows of bullets can be stacked on a pallet to essentially the same final height. In this way, the same pallet can contain 12 bullets of bags with L-shaped seams of 10 pounds of new style, as opposed to only 8 bullets of L-shaped bags stitched 10 pounds knitted raschel tí?

Traditional As a result, 48,000 10-pound bags of new style can be stored on a pallet, compared to only 24,000 L-stitched bags stitched with 10 pounds of prior art. In a given volume, fifty percent more bags can be transported and stored. The spatial requirements of transport and storage are drastically reduced, also reducing the carbon footprint of the bags. Table 4 confirms that similar improvements are obtained for 5-pound L-shaped stitched bags.

3. Molding, Filling and Closing Bags

The ultra-mesh materials as described herein, or other materials that have at least some of the characteristics of the ultra-mesh materials, can also be used to obtain bags of multiple substrates that have both open and mesh portions with at least one thermally bonded seam. Although embodiments of molding, filling and closing bags (FFS) that take the form of vertical molding, filling and closing bags (VFFS) of four panels will now be described, at least many of the concepts explained here are also applicable to other bags of molding, filling and closing vertical, bags of molding, filling and closing horizontal (HFFS), and any other FFS bags of multiple substrates that have at least one thermally bonded end seam that seals together portions of mesh and film from the bag.

Returning first to FIGS. 16-21 and FIGS. 16-18 in particular, a first embodiment of an FFS 1,020 bag comprises a VFFS bag called four

<img file="CO6541549A2_D0029.tif" />

panels that have front sides 1,022, rear 1,024, left 1,026, and right 1,028, and upper ends 1,030 and lower 1,032. The bag is filled with items such as items of crop products or other food products. The full term, as used here, does not mean that the entire interior volume of the bag must be occupied by the items. In fact, in commercial applications, a bag is typically filled to its valued weight of stored items, while the items occupy less than 70%, and often quite less than 50%, of the inner volume of the bag. Items that can be stored in these bags can be, for example, nuts, oranges, potatoes, onions, fish (such as prawns, mussels, or clams), newspapers, flower bulbs, dried beans, or wrapped candy.

The 1,020 bag is generally square along most of its length when filled with materials, except where it is collapsed at the upper and lower ends 1,030 and 1,032 where the opposite front and rear sides 1,022 and 1,024 are joined together, being arranged the ends of the left and right sides 1,026 and 1,028 forming a sandwich in between. It could also be rectangular or have another form of polygonal cross-section and show many of the features, if not all, explained here. The left and right sides 1,026 and 1,028 are formed from an open mesh material with 1,100 reinforced bottom. At least one end of each of the outer surfaces of the front and rear sides 1,022 and 1,024 is formed at least in part from a sheet material 1,102 extending in the longitudinal direction of the bag from a

<img file="CO6541549A2_D0030.tif" />

closed end of the bag. Extreme timbos of one or both front and back sides can be made of sheet material. In the illustrated embodiment, the sheet material extends the entire length of the front and back sides. In the bag 1,020 of the illustrated embodiment, the rear side 1,024 is completely formed from the sheet material 1,102, and the front side 1,022 of the bag 1,020 is formed from the open mesh material 1,100 superimposed with the sheet material 1,102 .

Referring to FIGS. 20 and 21, the sheet material 1,102 of the front side 1,022 of the bag 1,020 preferably extends over the entire width of the front side 1,022, but if desired it can be extended less than the entire width. 1,100 underlying mesh fabric is thermally closed at its edges via seams 1,034, 1,036 having approximately M inches (0.64 cm) at³/ g inches (0.95 cm) wide. The 1,024 back side of the 1,020 bag has two seams that extend 1,038, 1,040 vertically at its corners where the 1,102 film material overlaps the edges of the 1,100 open mesh fabric. Both seams 1,038, 1,040 comprise overlapping seams. At least the lower end 1,032 is closed, possibly by sewing or gripping, but more preferably by thermal bonding. In the illustrated embodiment, both upper and lower ends 1,030 and 1,032 of bag 1,020 are closed by thermally joined seams. These seams may take the form of fin or skin seams 1,042, '1,044 formed by pressing two closure bars together, also as explained below. Alternatively they could be formed by other seams such as overlapping seams. The upper and lower seams 1,042, 1,044 typically have a length L of about ³/ g inches (0.95 cm) to Y inches (1.27 cm). The 1,020 illustrated bag has a storage capacity of one to three pounds, and is about 4 inches (10.2 cm) wide by 10 inches (25.4 cm) high. However, the concepts explained here are equally applicable to larger or smaller bags of different proportions.

The sheet material 1,102 can be any sheet material capable of being thermally bonded to itself and other materials. Preferably it is able to receive distinctive marks on its outer layer. A material made in whole or in part from a synthetic resin film material could suffice. Such a material is the so-called PET laminate that has a thin layer of a relatively high melting point polyester material, which serves as a printing surface, laminated on a relatively thick layer of a linear low density polyethylene (LLDPE) material. of relatively low melting point. The LLDPE material melts during the thermal bonding process to close the film material to adjacent materials. A preferred material is approximately 3 mil (0.076 mm) thick. However, as explained in more detail below, other materials of different thicknesses have been successfully tested. Other sheet materials could also be used.

The 1,100 open mesh material is of an ultra-mesh type, and thus is formed from a number of intersecting filaments, at least some of which are composite filaments formed from a composite material having a high melting point support portion and a relatively low melting point joining portion. It can take the form of one of the nonwoven fabrics generally described above in conjunction with FIGS. 1-7.

Returning now to FIGS. 22 and 23, 1,020 bags can be manufactured in a vertical 1,050 molding, filling and closing machine that forms full bags of product from 1,060 and 1,062 rollers of 1,100 open mesh fabric and 1,102 sheet material, respectively. The 1,050 machine includes a 1,052 frame, a 1,054 substrate forming station, a 1,056 product dispenser, and a 1,058 molding, filling and closing assembly. The substrate forming section 1,054 forms a continuous belt of a 1,200 composite substrate from the 1,060, 1,062 mesh and film rollers. The 1.058 molding, filling and closing assembly receives batches of product from the 1,056 product dispenser and simultaneously forms 1,020 bags from the 1,200 substrate, fills those 1,020 bags with the product, and closes the ends of the molded and filled bags 1,020 .

The 1,054 substrate forming station includes 1,060 and 1,062 first and second feeder rollers for 1,100 open mesh fabric and 1,102 film, respectively. The open mesh fabric 1,100 is preferably wound on the roller in a continuous belt 1,202 with the warp filaments extending in the longitudinal direction of the tape or in the machine direction. The warp filaments can last extended vertically in the finished bags. The second feed roller 1,062 supports a roll of the laminated film material of

PET, printed with two adjacent repeat patterns of print marks placed side by side in alignment with each other. A 1,064 cutter is provided downstream of the 1,062 feeder roller and operates to cut the 1,102 film into two tapes that have distinctive marks or 1,066, 1,068 print bands. A system of guide rollers and guide bars guides the print bands 1,066, 1,068 and the continuous tape 1,202 of the open mesh fabric 1,100 in a substrate forming assembly

1,070, where the edge of the first print band

1,068 is thermally bonded to one edge of the 1,202 mesh tape, and the other 1,066 print band is thermally bonded to the outer surface of the 1,202 mesh tape in a separate relationship to the first print band

1,068. The segments of these 1,066 print bands,

1,068 last form the back and front of the finished bags, respectively. The thermal bonding is preferably carried out via a 1,072 hot rod system and a 1,074 iron as is generally known in the art. A suitable system for cutting film having marks printed on two bands and for thermally bonding the printed bands to a substrate is known, for example, from Winiecke International Publication No. WO 99/58323.

The resulting 1,200 substrate is illustrated in FIG.

24. It includes a continuous web of 1,202 mesh fabric having a 1,066 printed band superimposed on an outer surface about halfway between the first and second 1,204, 1,206 edges of the 1,202 mesh tape. The 1,066 printed band is thermally bonded ,,, mind to the 1,202 mesh tape on flap seams: · 1,208 and 1,210 that are parallel to the edges of the / 0

L &amp;&gt;

- 56 printed band 1,066. A first edge 1,212 of the other band 1,068 is thermally bonded to the second edge

1,206 of the 1,202 mesh tape via a 1,214 overlap seam. When the 1,200 substrate is subsequently molded into a bag, a segment of the first print band 1,066 forms the outer surface of the front side of the bag, a segment of the second print band 1,068 forms the back side of the bag, a segment of a portion of 1,216 mesh between the first and second 1,066 and 1,068 print bands forms the right side wall of the bag, and a segment of the mesh portion 1,218 to the left of the first print band 1,066 forms the left side wall of the bag.

It should be noted that the substrate 1200 does not need to be molded in the vertical molding, filling and closing machine 1,050. Instead, it could be molded by a separate conversion equipment located in the same location as the vertical molding, filling and closing machine 1,050 or completely in another location. Optionally, the formation of the substrate in a remote location could offer the bag manufacturer the option of not having to buy and manipulate multiple rollers of different types of materials. It would also reduce the capital expenditure associated with the purchase and operation of the vertical molding, filling and closing machine, because the machine would not require a substrate forming station.

Referring again to FIG. 22, the 1,056 product dispenser works to dispense batches of product that have been weighed by a computer weighing apparatus (not shown) at the appropriate time.

<img file="CO6541549A2_D0031.tif" />

<img file="CO6541549A2_D0032.tif" />

Do in the machine operating cycle 1,050. Suitable computer weighing devices that can perform this function are shown in US Pat.^s 4,538,693 and 4,901,807, which are incorporated herein by reference.

Referring to FIGS. 22 and 23, the 1,050 molding, filling and closing assembly includes a 1,080 square vertical molding tube mounted on the 1,052 frame immediately below the 1,056 dispenser, so that the product dispensed from the 1,056 dispenser is received internally from the 1,080 vertical molding tube . A 1.082 molding shoulder is secured to the adjacent 1,052 frame but separated from an upper end of the 1,080 vertical molding tube. Other polygonal shaping tubes, or even circular or ovoid tubes, could be used instead of a square shaping tube. The molding shoulder 1,082 directs the 1,200 substrate around the molding tube 1,080 to form a generally square tubular structure in which the outer edge of the 1,068 printed web overlaps the outer surface of the opposite edge of the 1,202 mesh fabric tape. A vertical seal bar 1,084 is supported adjacent to the upper end of the vertical mold tube 1,080. The vertical sealing bar 1,084 thermally joins the overlapping edge of the printed web 1,068 to the outer edge of the 1,202 mesh fabric tape at the corner of the front of the finished bag, to form a vertical overlap seam, thus forming a sleeve generally tubular 1,087. A pair of 1,086, 1,088 feed belts is located on opposite sides of the 1,080 vertical molding tube below the 1,084 sealing bar. The tapes 1,086, 1,088 are controlled sectically to index the sleeve 1,087 down along the tube 1,080 the length of a bag 1,020 to advance a corresponding amount of the substrate 1,200 and in contact with the shaping shoulder 1,082 and allow another 1,020 bag.

A 1,090 terminal sealing and cutting device is located under the 1,080 tube. The 1,090 device includes a pair of opposite heated sealing bars 1,092, 1,094 that are selectively movable with each other to horizontally compress the sleeve 1,087 above the level of the product in the full bag to form a flap closure forming the upper side seam 1 , 042 in the 1,020 bag containing the product, and a lower side seam 1,044 in the next 1,020 bag to be filled with the items. The seam is formed by heating the bonding layers of the various materials to bond the first and second 1,066, 1,068 print ribbons with each other and the intervening layers of 1,202 mesh tape, generally as seen in FIG. 2. 3. The 1,090 device also includes a blade (not shown) that cuts the full and closed bag 1,020 from the rest of the substrate sleeve 1,087 so that the full and closed bag 1,020 falls down onto a conveyor belt 1,051 that transports the full bag and 1,020 closed away from the 1,050 machine.

1,096, 1,098 left and right tongue blades are provided below the discharge opening in the 1,080 tube immediately above the 1,090 closing and cutting device. The blades are actuated by actuators such as pneumatic cylinders 1,097 and 1,099 to fold the center of the left and right sides 1,026 and 1,028 of the bag 1,020 between the edges of the

<img file="CO6541549A2_D0033.tif" />

1,022 and 1,024 front and rear sides just before the closure of the 1,092, 1,094 closure bags, thus forming tabs on the sides of the 1,020 bag. The blades 1,096, 1,098 are retained in this position during the heating and closing operation, and are removed simultaneously with the sealing bars of the 1,090 closing and cutting device. The depth of the tongues varies with the travel of the tongue blades 1,096, 1,098. In the illustrated embodiment, the tabs extend towards the center or almost towards the center of the bag 1,020, as can be seen in the bottom view of FIG. twenty.

The open, relatively light weight nature of the ultra-mesh material that forms the open mesh material 1,100 of the finished 1,020 bag, coupled to the composition of its filaments, allows the vertical molding, filling and closing machine 1,050 to produce superior seams and inferiors excellent at a speed much higher than would otherwise be possible with previously known multi-substrate materials that have other open mesh materials. The nature of that seam can be seen with reference to FIG. 19. The low density material of the various layers melts during the heat sealing process, and flows between and around the high density filaments. This results in at least partial encapsulation of the support portions of the filaments of the layers of the mesh material opened by the low density material. Importantly, it also allows significant film-to-film bonding of the outer film layers 1,022 and 1,025 through the openings in the mesh layers 1,026 and 1,028. The 1,100 tramalla material also has relatively low friction kinetic coefficients when compared to some other open mesh materials, enhancing the ability to pull substrates containing that mesh material through the 1,050 machine at higher speeds without slipping. . Tests have shown that multi-substrate VFFS bags with a seam strength that is much higher than that present in prior art bags can be manufactured at a rate of 25 bags per minute, or even 50 bags per minute or more . VFFS bags of multiple comparable substrates, which use CLAF® grade MS as the open mesh material of their substrates, can be manufactured at a speed of no more than about 15-22 bags per minute. The tests that confirm these conclusions are detailed below.

Referring again to FIGS. 16-18 and 27, the thus molded, filled and closed bag 1,020 is aesthetically pleasing because the front side 1,022 film tape is very smooth over the relatively thin, light weight underlying open mesh of the 1,100 layer formed to from an ultramalla material. In addition, the 1,100 underlying open mesh material has greater dimensional stability than traditional knitted and extruded mesh fabrics. Unlike the previous knitted and extruded mesh fabrics used in bags, the stability of the open mesh material 1,100, coupled with the geometry of the bag in which the lateral tabs of the polygonal bag descend almost to the longitudinal center line of the bag, constrict the items in the bag to the shape of the bag. Therefore, the 1,020 bag retains its square, rectangular, or other polygonal shape after it is filled with the items. The desired degree of tongue formation may vary with, for example, bag sizes. Generally speaking, a shallower tongue formation is necessary to achieve dimensional stability in larger bags. The 1,020 bag can even stand up and generally retains its shape.

The superior dimensional stability of the molding, filling and closing bags 10 constructed as explained herein allows the described bags to retain their desired height and transverse shape remarkably well even when filled with products. A 1,020 bag constructed as explained above in relation to the

FIGS. 16-21 using the ultra-mesh material A as a mesh material is shown after it has been molded, filled and placed on a flat surface such as a table. Tests have shown that when that bag is filled to its appraised weight with items and placed on a flat surface, it retains a high percentage of its initial height. The initial height, H_If As defined here, it is the vertical distance between the bottom surface of the bag to the location that the upper inner surface will form after the bag is closed, as measured just before the bag is filled with the items during the process of molding and filling. That height can be measured or at least estimated with a reasonable level of precision during the molding and filling process by measuring the distance from the bottom of the bag to the bottom end of the filling tube (see FIGS. 22 and 23) before of introducing items in the bag. The final height, H_F, as defined here, is the vertical distance between the bottom surface of the bag to the top of the items in the bag, after the bag has been molded, filled with the 'items, and placed on a surface without be supported from the top or from the sides. This final height could also be considered as the final effective height of the bag since the inner area of ​​the bag above the product is effectively discarded. Tests have revealed that the final height H_Fi of bag 1, 020 is at least 35% of the initial height. In fact, it has been found that the final height H_Fi is more than 50%, and even more than 60% of the initial height Hi of the bag.

The beneficial effects of this superior dimensional stability can be seen with reference to FIG. 27, in which the 1,020 bag is shown side by side with molding, filling and closing bags 1,021 and 1,023 of the prior art. The 1,021 bag is made of a commercially available tubular knitted synthetic mesh fabric from GIRO GH SA of Badalona, ​​Spain, under the trade name GIRO®. The 1,023 bag was molded from an extruded mesh fabric commercially available from Conwed Global Netting Solutions, Minneapolis, MN under the trade name VEXAR®. FIG. 27 shows that heights H_F and H_F of bags 1,021 and 1,023 are much smaller than the final height H_F of a bag produced in accordance with this description. Bags 1,021 and 1,023 sink to a great extent, while there is virtually no collapse of a bag constructed in accordance with the present description.

The height retention characteristics visually represented in FIG. 27 were calculated numerically * and recorded for a sample of the new bag. The bags obtained from both the GIRO® and VEXAR® materials were 2-pound bags containing Clementine oranges. The new bag was a 3-pound bag built as described here in conjunction with FIGS. 16-21 and that has the ultra-mesh material A as its open mesh material. For each bag, the initial and final heights H_x and H_F were measured and recorded, and the percentage of height retention (Hf / Hj) X 100 was calculated and recorded. The differences in appraised capacity and the nature of the items stored between the new style bag and the bags of the Prior art was not believed to significantly affect the percentage of height retention. The results are tabulated in Table 5 below, in which the various bags are identified by the mesh material contained in the bag:

TABLE 5: RETENTION OF THE HEIGHT OF THE FFS BAG

<td rowspan="2">Mesh Type</td><td rowspan="2">Initial Height of the Bag (cm)</td><td rowspan="2">Final Height of the stock market (cm)</td><td colspan="2">Retention of</td>

<td>the height</td><td> (%)</td>

<td>GIRO® Circular Knitting</td><td> 36,8</td><td>CO kO</td><td colspan="2"> 24</td>

<td>Extruded Network VEXAR®</td><td> 35,7</td><td> 8,9</td><td colspan="2"> 24</td>

<td>Ultramalla A</td><td> 34,9</td><td> 22, 9</td><td colspan="2"> 66</td>

The measurements recorded in Table 5 confirmed that the bags of multiple substrates constructed using an ultramalla material showed a retention of the

<img file="CO6541549A2_D0034.tif" />

Atura drastically improved with respect to the circular knitted and extruded net bags of the prior art.

The dimensional stability of the 1,020 bag is also reflected by its high perimeter stability. Perimeter stability, as used herein, refers to the ability of a bag to maintain a constant cross-sectional shape and a constant perimeter value along at least a substantial portion of the bag's length after it is filled and placed on a surface in an unsupported manner, that is, without being otherwise supported from the top or from the side. It is another measure of sinking. Any VFFS bag will have an initial diameter and a resulting initial perimeter that essentially coincides with those of the tube from which it is molded, and that diameter Dj; It will be relatively uniform along at least most of the length of the bag. A bag with a high perimeter stability will show little sinking, and therefore will have a maximum final diameter D_Fwhich is relatively close to the initial maximum diameter of the bag, which can be assumed to be the same as the diameter of the molding tube in the VFFS machine. That is the case with the 1,020 bag constructed using the ultramalla material A, in which D_F/ Di X 100 is at least 70% and even 90% or even more. On the contrary, D_F/ D]; X 100 for prior art bags obtained from GIRO® circular knitting material and VEXAR® extruded netting materials of the prior art are typically less than 50%.

The ultramalla material also offers excellent ventilation of the items stored in the bowl. The superior stitching resistance of the bag

1,020 allows larger and / or larger capacity bags to be produced. The ability to form seams quickly and stretch the substrate through the machine allows the bags to be molded and filled at higher speeds.

In FIG. 25 shows an alternative bag configuration 1,220. Bag 1,220 is identical to bag 1,020 of FIGS. 16-21 in all aspects except for the fact that the front side. 1,222 is formed only from a 1.202 thermoplastic film tape as opposed to a thermoplastic film tape superimposed on an open mesh fabric. Note the cutting portion 1,223 in FIG. 25. A substrate

1,300 to obtain that bag, shown in FIG. 26, consists of two separate 1,316 and 1,318 ribbons of an ultramalla material that are linked together by two 1,266, 1,268 printing bands. The 1,266 print band bridges the space between the two tapes and stops 1,316 and 1,318. Referring again to FIG. 25, the 1,224 rear side and the 1,226 and 1,228 pleated left and right sides are identical to the corresponding 1,024, 1,026 and 1,028 sides of the bag

1,020 of the first embodiment. Closures on opposite ends of upper and lower seams

1,242, 1,244 are also identical to those of the bag of the first embodiment along at least most of its length.

Bag 1,220 of FIG. 25 also has 1,250, 1,252 horizontally separated finger holes, formed through the bag from front to back between two separate seams 1,242, 1,242 'and / "'

<img file="CO6541549A2_D0035.tif" />

close to the top of the bag, to allow the bag to be supported at least in part by inserting the fingers through the holes. The 1,250, 1,252 holes can be drilled through the bag by means of punches mounted in or otherwise that work in combination with the 1,090 sealing and cutting device of the 1,050 molding, filling and closing machine, or by other equipment completely. In order to cancel the need for targets or handle plugs that would be produced by removing all the material from the drilled holes, the holes are preferably drilled so that they leave flaps. Bag 1,020 of FIGS. 16-21 could also be molded with finger holes, if desired.

EXAMPLES

The superiority of the seam strength achieved through the use of the substrate described above was confirmed by several series of tests designed to reproduce the terminal seals formed from flap seams in a bag. Except as otherwise noted, the material tested comprised a 1 inch (2.54 cm) wide ribbon of a layered fabric composed of first and second opposite outer layers of the PET film material described above and four layers which intervene in the ultramalla material that represents the pleated area at the ends of a bag of four pleated panels. The composition of the ultramalla material varied from test to test. These material belts were then fastened between two heated bars, designed to simulate the closing bars of a vertical molding, filling and closing machine, at a clamping pressure of 700-710 kPa during

<img file="CO6541549A2_D0036.tif" />

- 67 specific time periods or residence times. Residence times varied from one trial to another. The seam was subsequently separated by pulling the joined materials from the top and from the bottom until the seam broke, and the maximum force applied and the time required to reach that force after the force was initially applied. Each of these series of trials will now be described and the conclusions drawn from them.

Test Series 1 - Co-Ex / HDPE Mesh, 10 mm

In this series of tests, a substrate having an ultra-mesh material in the form of a nonwoven fabric of the type generally shown in FIGS was tested. 4-7.

The tissue had a density of 20 g / m² and consisted of two layers of warp of a coextruded filament flanking two layers of weft of high density polyethylene (HDPE). The warp filaments extended parallel to the machine direction. The weft filaments extended at included angles of about 40 ° in relation to the transverse direction of the machine. Therefore, each filament was extended at an angle of about 20 ° in relation to the transverse direction of the machine. Each weft filament was formed from '25 of an 80 micrometer thick three layer tape having a 50 micrometer thick layer of HDPE and interposed between two 15 micrometer thick layers of a linear low density polyethylene LLDPE The tape was stretched at a ratio of 6: 1 to form the filaments, 30 coughs that were incorporated into the tissue, after which j the composite filament had a thickness of about * - «· · 0,03 mm and a width of about 1.5 mm. The weft rows of each layer were separated by 10 mm. The fabric was an alternating fabric in which the warp filaments of the lower layer separated approximately midway between the warp filaments of the upper layer, leading to a spacing of the warp filament in the fabric of about 5 mm. Each filament of the weft layer had a thickness of about 0.04 mm and a width of about 1.5 mm. Three samples were tested under the conditions summarized in Table 6 below.

TABLE 6: COEX / HDPE MESH CLOSURE CHARACTERISTICS, 10 MM

<td rowspan="2">Sample</td><td rowspan="2">Temp. (° C)</td><td rowspan="2">Time of Home (S)</td><td rowspan="2">Max force (N)</td><td colspan="2">Time for</td>

<td>Max force</td><td>(S)</td>

<td> 1</td><td> 149</td><td> 0,75</td><td> 6, 6</td><td colspan="2"> 0,68</td>

<td> 2</td><td> 149</td><td> 0,75</td><td> 6,2</td><td colspan="2"> 0,46</td>

<td> 3</td><td> 149</td><td> 0,25</td><td> 8,0</td><td colspan="2"> 0,62</td>

This series of tests revealed that the formation of the bags under the operational conditions of heat and residence time required to form acceptable closures on a substrate that has an ultra-mesh material as its mesh portion produced a very strong closure. The time required to reach maximum force, which serves as a measure of how quickly the seam formed, was more than acceptable. Unexpectedly, it was discovered during trial # 3 that, reducing residence time to only 0.25 seconds, there was actually a stronger closure of 8.0 N.

I

<img file="CO6541549A2_D0037.tif" />

Test Series 2 Co-Ex / Co-Ex stacked, 8 mm

The open mesh material of the substrate of test series 2 was similar in construction to that shown in FIGS. 1-3. It consisted of an ultra-mesh material formed from two aligned or stacked warp filaments that flank weft filaments that intersect. Both warp filaments and weft filaments were three coextruded filaments of the type described above in conjunction with Test Series 1. The warp filaments separated 8 mm apart. The results of the tests are summarized in Table 7:

TABLE 7: CHARACTERISTICS OF THE CLOSURE OF CO-EX APILADO, 8

MM

<td rowspan="2">Sample</td><td rowspan="2">Temp. (° C)</td><td rowspan="2">Time of Home (S)</td><td rowspan="2">Max force (N)</td><td colspan="2">Time for</td>

<td>Max force</td><td>(S)</td>

<td> 1</td><td> 149</td><td> 0,25</td><td> 5, 5</td><td colspan="2"> 0,48</td>

<td> 2</td><td> 14 9</td><td> 0,17</td><td> 4,5</td><td colspan="2"> 0,22</td>

<td> 3</td><td> 149</td><td> 0,10</td><td> 3,7</td><td colspan="2"> 0, 35</td>

<td> 4</td><td> 143</td><td> 0,10</td><td> 5,5</td><td colspan="2"> 0, 39</td>

<td> 5</td><td> 138</td><td> 0,10</td><td> 6, 6</td><td colspan="2"> 0,45</td>

<td> 6</td><td> 138</td><td> 0,10</td><td> 6, 6</td><td colspan="2"> 0,38</td>

These tests revealed that the excellent fin seam strengths in proportion to the ob20s served in Test Series 1 were obtained at even smaller residence times and reduced temperatures. The fact of producing seams of these resistors

<img file="CO6541549A2_D0038.tif" />

High residence times of the order of only 0.10 seconds would easily allow the production of vertical molding, filling and closing bags in the machine described above, at speeds greater than 50 bags per minute.

Test Series 3 - Co-Ex / HDPE Mesh, 10 mm

In Test Series 3, the same ultra-mesh material tested in Test Series 1 was tested at reduced temperatures and reduced residence times.

The results are summarized in Table 8.

TABLE 8: CO-EX / HDPE MESH CLOSURE CHARACTERISTICS,

MM

<td rowspan="2">Sample</td><td rowspan="2">Temp. (° C)</td><td rowspan="2">Time of Home (S)</td><td rowspan="2">Max force (N)</td><td colspan="2">Time for</td>

<td>Max force</td><td>(S)</td>

<td> 1</td><td> 149</td><td> 0,10</td><td> 6, 6</td><td colspan="2"> 0,28</td>

<td> 2</td><td> 132</td><td> 0,10</td><td> 6, 6</td><td colspan="2"> 0,42</td>

<td> 3</td><td> 132</td><td> 0,10</td><td> 6,2</td><td colspan="2"> 0,39</td>

<td> 4</td><td> 127</td><td> 0,10</td><td> 1,8</td><td colspan="2"> 0,27</td>

Unexpectedly, it was observed that very strong fin closures were found that have failure forces greater than 6.0 N at a residence time of only 0.10 seconds at temperatures as low as 132 ° C. A significant reduction in seam strength was observed only at temperatures below 130 ° C.

Test Series 4 - Co-Ex / HDPE Preetlabel Mesh, 10 mm

The substrate tested in this series of tests was

<img file="CO6541549A2_D0039.tif" />

identical to the ultramalla material that was tested in Test Series 1 and 3 above, except for the fact that the substrate was pre-labeled with a laminated PET 3.0 material that is 3.0 mil (0.076 mm) thick. That is, the film material tapes were bonded to the ultra-mesh material using a separate conversion equipment instead of the conversion equipment used in the vertical molding, filling and closing machine described above. The test results are summarized in Table 9 below:

TABLE 9: CHARACTERISTICS OF THE CLOSURE OF THE MESH

CO-EX / HDPE PREETIQUETTED, 10 MM

<td rowspan="2">Sample</td><td rowspan="2">Temp. (° C)</td><td rowspan="2">Time of Home (S)</td><td rowspan="2">Max force (N)</td><td colspan="2">Time for</td>

<td>Max force</td><td>(S)</td>

<td> 1</td><td> 149</td><td> 0,10</td><td> 5,6</td><td colspan="2"> 0,32</td>

<td> 2</td><td> 149</td><td> 0,10</td><td> 11,0</td><td colspan="2"> 0,57</td>

<td> 3</td><td> 149</td><td> 0,10</td><td> 6, 0</td><td colspan="2"> 0,35</td>

<td> 4</td><td> 149</td><td> 0,10</td><td> 5,4</td><td colspan="2"> 0, 45</td>

These tests confirmed that seam strengths in proportion to those explained above can be obtained with pre-labeled substrates at bag production rates in proportion to those explained above in conjunction with Test Series 1 and

3.

Four. Multiple Substrate Bags

As indicated above, the open mesh materials described herein can be used to obtain the mesh portions of multi-substrate bags that have both film and open mesh portions. Multi-substrate bags are bags that have opposite first and second side walls in which at least a substantial part of one of the side walls is made of an open mesh material, and at least a substantial part of the other side wall is Made of a sheet material. The first and second side walls can be closed directly together or can be interconnected by additional side walls extending spaces between the first and second side walls.

Returning now to FIGS. 28-35 and initially to FIGS. 28-30 in particular, a 2,020 bag constructed in part from an open mesh material comprises a bag having front and rear faces 2,022 and 2,024, left edges 2,026 and right 2,028, and upper ends 2,030 and lower 2,032. The matching faces of the side edges 2,026 and 2,028 are formed from joined flap seams, but could be formed from overlapping seams or other seams. At least a substantial portion of the first side wall 2,022 of the bag 2,020 is formed from a tape 2,034 of an open mesh material. A reinforcement tape 2,036 can be provided on the upper edge of the first side wall 2,022 to reinforce the upper edges of the side seams 2,026, 2,028, thereby inhibiting the seams 2,026, 2,028 being separated during a bag filling operation and subsequent manipulation.

Referring now to FIGS. 28-30, the second side wall 2,024 of the illustrated embodiment is

<img file="CO6541549A2_D0040.tif" />

completely form a sheet material. Alternatively, a mesh tape could be provided within the second side wall of the bag between the upper and lower ends 2,030 and 2,032. As yet another alternative, the entire lower portion of the second side wall 2,024 could be formed as the same open mesh material or different from the first side wall 2,022, and the upper portion could be formed from a sheet material. In this case, the first and second side walls could be at least generally the same construction. Regardless of the construction of the second side wall 2,024, ventilation holes or vents 2,025 can be formed in the sheet material if desired.

One or more of the ultramalla materials of the type described in Section 1 above, including but not limited to one or more of the materials illustrated in FIGS. 1-7, it is very suitable for mesh material.

The film tape that forms the second side wall 2,024 is formed from a sheet material, such as a film material. Such film material is formed at least in part from a synthetic resin film material, such as polyethylene or polypropylene, numerous types of which are commercially available. An example is a coextruded three layer film having an outer layer formed by LLDPE, a central layer formed by a mixture of LLDPE, and an internal layer formed by a premium LLDPE. The film can be easily converted into bags using existing bag collection equipment, and can be handled well using existing bag filling machines. It also complies with the FDA for direct contact with

<img file="CO6541549A2_D0041.tif" />

<img file="CO6541549A2_D0042.tif" />

foods. It can also be dyed or colored as desired, and can receive printed marks on its outer surface. Another exemplary film is 2.25 mil (0.057 mm) LDPE with an EVA additive.

The thickness of the film will vary with the type of film and the intended application, including the size of the bag in which the film is intended to be used. For a three-layer coextruded film of the type described above, the film will typically have a thickness of about 1.35 thousand. (0.034 mm) to 1.5 mil. (0.38 mm) for a 5-pound bag, and about 1.65 thousand. (0.042 mm) to about 1.75 thousand. (0.44 mm) for a 10-pound bag.

The particular horizontal and vertical dimensions of the side walls 2,022, 2,024, as well as their thicknesses, are typically determined based on the expected weight and size of the crop products to be packaged in the bag by an automatic machinery that packages crop products. It should also be noted that bag sizes are generally referred to in the art in terms of their storage capacity in pounds. Therefore, a 5-pound bag of a given style is one that has a size to contain 5 pounds (2.27 kg) of a particular item or type of item. The table below gives exemplary dimensions for various bag sizes:

CROP PRODUCT WEIGHT

BAG WALL DIMENSION

<td>2 pounds</td><td> (0, 91</td><td>kg)</td><td> 10</td><td>inches</td><td> (25,4</td><td>was)</td><td>by</td><td>16 inch</td><td> (40, 6</td><td>cm)</td>

<td>3 pounds</td><td> (1,4</td><td>kg)</td><td> 10</td><td>inches</td><td> (25, 4</td><td>was)</td><td>by</td><td>16 inch</td><td> (40, 6</td><td>cm)</td>

<td>4 lbs</td><td> (1,8</td><td>kg)</td><td> 10</td><td>inches</td><td> (25, 4</td><td>was)</td><td>by</td><td>18 inch</td><td> (45, 7</td><td>was)</td>

<td>5 pounds</td><td> (2,3</td><td>kg)</td><td> 10</td><td>inches</td><td> (25,4</td><td>cm)</td><td>by</td><td>18 inch</td><td> (45,7</td><td>cm)</td>

<td>10 pounds</td><td> (4,5</td><td>kg)</td><td>Ib</td><td colspan="2">5 inches (26,</td><td colspan="4">, 7 cm) by 23 inches (58,</td><td>. 4 c</td>

<img file="CO6541549A2_D0043.tif" />

The vertical side seams 2,025, 2,028 may have any desired width depending on the desired holding strength for the 2,020 bag along its vertical side seams. The widths of the order of³/_s inches (0.95 cm) to ⁵/ e inches (1.59 cm). The joining of the side walls 2,022 and 2,024 in the seams 2,028 can be carried out by any suitable joining or sealing technique, such as heat, glue, sealant, or the like, using any number of machines for obtaining existing bags. Thermal bonding is preferred.

Referring to FIGS. 31 and 35, the lower part of the side wall of the film 2,024 extends beyond the lower part of the side wall of the mesh 2,022 to form a flap 2,046 which folds back on the outer surface of the side wall of the mesh 2,022 forming a small gap 2,048 between the bottom edge of the mesh tape 2, 034 and the bottom 2,032 of the bag 2,020. The flap 2,046 is thermally bonded to the 2,034 mesh tape to form a horizontally lower overlapping seam 2,050. As a result, the lower part 2,032 of the interior of the bag 2,020 is formed a) from a folding in the inner wall of the film 2,024 instead of from a seam. The length of the flap 2,046 and the degree to which the mesh tape 2,034 overlaps may vary with the intended application and the manufacturer's preference. In the illustrated embodiment, the length of the flap 2,046, from the

4/30 bottom edge 2,032 of bag 2,022 to the top of flap 2,046, is about 3.5 inches

B (8.9 cm). Overlap the mesh tape at around 1.25

<img file="CO6541549A2_D0044.tif" />

L80-,

Ί6 inches (3.2 cm).

Alternatively, the 2,234 mesh tape could extend to almost the bottom of the 2,220 bag as seen in FIG. 31B, or it could be extended in 5 clusters further to the front face of the 2,220 bag illustrated in FIG. 31. Bag 2,220 of the embodiment of FIG. 31B is otherwise identical to the bag of FIGS. 28-31 and 32-35. The elements of this embodiment are therefore designated by the same reference numbers as the elements of the embodiment of FIGS. 28-31 and 32-35, incremented by 100. The same augmentation technique is used to designate corresponding portions of the various embodiments.

The provision of at least the bottom end of the bag from a bag of folded resin film considerably reinforces the bag 2,020 and substantially reduces the chances of failure during a bag filling and subsequent handling operation because the items that fall into the bag impact against the relatively strong folding, as opposed to a relatively weak seam. However, this particular bottom configuration is not critical. For example, more conventional raid seams of the type described could also be used, for example, in US Patent No. 3,554,368, or pearl seams of the type described, for example, in US Patent No. 3,123. 279.

Holes for fixing pins 2,040 could be formed in an extension of one of the side walls30 to allow hanging the 2,020 bag with * pins, fixing of bag filling equipment of commercially available automatic crop products, for example

<img file="CO6541549A2_D0045.tif" />

Tweet, from Ag-Pak, Inc. of Gasport, NY, or Volm Companies of Antigo, WI. The holes for fixing pins 2,040 should be arranged to cooperate with fixing pins to allow the bag 2,020 to be suspended in an automatic crop product packaging machine as it is filled with crop products or another product. The size, location and number of fixing holes 2,040 is based on the nature of the particular bag filling machine with which the bags are to be used. A typical fixing hole has approximately⁵/ g inches (1.6 cm) in diameter. The side of the bag opposite the side that has the¹ Fixing hole is usually considered the front of the bag, because that side looks out when the bag is filled. In the illustrated embodiment in which the mesh side wall 2,022 forms the front part of the bag 2,020, the fixing holes 2,040 are formed in a portion 2,039 of the side wall of the film 2,024 that extends above the supe20 part rior of reinforcement tape 2,036 (see FIGS. 28, 29 and 35). The 2,039 portion could also be formed from a tape separated or integrally with the rest of the side wall of the 2,024 film. As an alternative, '· goes, referring to FIG. 31A, the fixing holes 2,140 could also be formed in the reinforcement tape 2,136, in which case the reinforcement tape 2,136 would preferably extend above the top of the side wall of the film 2,124 of the bag 2,120.

Referring again to the bag of

FIGS. 28-30, 2,042 openings or leaders can be cut above the 2,040 fixing holes to help (S '²78 to be removed from the bag 2,020 from the fixing pins of the filling machine once the bag

2,020 is full.

The 2,040 fixing holes could all be removed together if the 2,020 bag is to be filled manually or via bagging equipment that lacks fixing pins. Instead of or in addition to having fixing holes, the upper part of a 2,320 bag could be formed with 2,360, 2,362 stretch sleeves as seen in FIG. 31C. Each of the 2,360 and 2,362 stretch sleeves of the embodiment is formed of a synthetic resin film comparable to that of the 2,324 rear side wall. The sleeves could be integrally formed with the 2,324 wall film tape and the 2,336 reinforcement tape, respectively, or they could be thermally attached or otherwise fixed to the upper ends of those tapes. Each 2,360, 2,362 stretch sleeve is formed by folding an extension of the associated resin tape down and out to form a fold. A 2,364, 2,366 stretch belt or band is retained in each of the 2,360, 2,362 stretch sleeves. The terminal portions of each 2,364, 2,366 stretch band are joined or sealed within the associated sleeve 2,360, 2,362. Stretch bands 2,364, 2,366 can be accessed via notches or openings (not shown) in the central portions of the 2,360, 2,362 stretch sleeves and can be pulled to close the 2,320 bag at its top.

The reinforcing tape 2,036 can be formed from any of a number of sheet materials. Preferably it is formed from the same material as the rear side wall 2,024. Referring to FIGS.

“7 ^ V8&gt;

28, 29, 31, 33 and 35, the reinforcement tape 2,036 has a horizontal length that is equal to the width of the bag 2,020, a vertical width W, an upper edge, a lower edge, and a pair of side edges. The reinforcement tape 2,036 overlaps the outer surface of an upper edge of the mesh tape 2,034 of the bag sufficiently to allow the reinforcement tape 2,036 to join the mesh tape 2,034 through a horizontal upper seam 2,060 located very far below the upper edge of the reinforcing tape, but located very close to the upper edge of the 2,034 mesh tape. (Alternatively it could be placed between the walls 2,022 and 2,024, in which case it would hook to the inner surface of the 2,034 mesh tape). The vertical width of the flap does not need to be longer than is necessary to allow the formation of a suitable joint between the reinforcement tape 2,036 and the side wall of mesh 2,022. Since the seams are typically of the order of l inches (1.27 cm) to³/ 8 inches (1.0 cm) wide, the width of the overlap does not need to be significantly greater than ³/ 8 inches (1.0 cm) to inches (1.3 cm). However, it should be noted that the overlap width could be considerably larger without departing from the scope of the present description. A wider overlap allows printing of printed marks on the upper portion of the mesh side of the bag. In the illustrated embodiment of a bag of 5-pound crop products, the 2,036 reinforcement tape extends about 5 k inches (14.0 cm) above the 2,034 mesh tape. The exposed length of the mesh tape 2,034, between the bottom of the reinforcement tape 2,036 and the top of the folding

2,046, is about 8 inches (20.3 cm).,

Referring again to the drawings of the bag of FIGS. 28-31 and 32-35, and particularly FIG. 34, the open mesh material used in the 2,020 bag is formed from both weft and warp layers of a coextruded material as described above in conjunction with FIGS. 4-7. The weft filaments intersect at an included angle α of about 25 ° -35 ° relative to the vertical or transverse direction of the machine, or, more typically, about 30 °. Therefore, each individual filament extends at an acute angle of about 7.5 ° -10 ° relative to the transverse direction of the machine. Each diamond in the pattern has a width W of about 38 to 42 mm, and more typically about 40 mm, and a height H of about 16 to 18 mm, and more typically about 17 mm. The warp filaments are of an alternating configuration as described above, the filaments of each layer being separated from each other by about 8 mm, providing a filament to filament spacing of approximately 4 mm when viewed through tissue depth.

Returning now to FIGS. 36 and 37, a 2,420 bag is shown that is constructed using an alternative open mesh fabric that is generally the same as the open mesh material described above in relation to FIGS. 28-31 and 35. The height H, the width W, and the included angle α of the diamonds formed by the crossing of the weft filaments are the same as described in relation to FIG. 3. 4. The alternating fabric warp layers are approximately separated.

<img file="CO6541549A2_D0046.tif" />

» »

4 mm in most of the tape length when viewed through tissue depth. However, extra filaments or threads are provided at the ends of the 2,434 mesh tape at the upper and lower horizontal seams 2,450 and 2,460 when the 2,434 mesh tape is overlapped by and is closed by the flap of the film side wall and reinforcement tape 2,436, respectively. In these areas, the number of warp filaments doubles, so that the separation between adjacent filaments, when viewed through the depth of the 2,434 mesh webbing, is reduced from about 4 mm to about 2 mm, increasing the surface area available for bonding and increasing seam strength at the top and bottom of the 2,434 mesh tape.

As mentioned above in relation to the explanation of the ultramalla material, the angles and dimensions of the diamonds formed by the weft filaments that intersect can be optimized for the desired application. In order to highlight this fact, in FIGS. 38 and 39 illustrate another alternative construction of a 2,520 bag. Bag 2,520 is identical to bag 2,420 of FIGS. 36 and 37 (including the provision of additional warp filaments in the areas of the 2,550 and 2,560 seams), except for the fact that the weft filaments of the 2,534 open mesh fabric tape extend at a less pronounced angle relative to to machine direction, producing a slightly more open mesh structure and improving visibility and ventilation while potentially reducing seam strength. The weft filaments are cru i

zan at an angle included at around 40 ° -50 ° relative to the vertical or transverse direction of the machine, and more typically around 46 °. Each individual filament thus extends at an angle of 20-25 ° in relation to the transverse direction of the machine. Each diamond of the pattern has a width of about 38 to 42 mm, and more typically about 40 mm, and a height of about 11 to 13 mm, and more typically about 12 mm.

EXPERIMENTAL DATA

Several variations or styles of bags of multiple substrates have been constructed and tested for various characteristics. The bags were subjected to several different tests, and were compared with prior art bags subjected to the same tests. The test procedures and test results will now be detailed.

1. Fall Assay

The purpose of a drop test is to determine the resistance of a bag seam by dropping the bag from a given height a number of times. Each bag is considered to pass the test if all its seams survive the maximum number of falls (25 in the procedure used by the examiners) without any of the seams failing. The bags were filled with balls to the nominal weight, and dropped from a height of 20 inches (50.8 cm). A bag is considered to fail if, after any fall, any of its seams is torn or broken to a length greater than an inch (2.5 cm). Each bag style was given an AF grade, depending on the average number of falls that the bag style survived without sewing failure. Stock exchanges that survive an average of almost 25 falls were given a grade of A; Stock market styles that fail in the first four falls are given a grade of F. The degrees of CD were assigned on a linear basis between these two extremes.

2, Peeling Test

The peel test is another more objective method to test the strength of the seam. Each type of seam (lateral, upper horizontal, and lower horizontal) is tested by manually pulling the mesh and film materials from a statistically significant number of each bag style at generally straight or greater angles. If the open mesh material detaches relatively easily from the sheet, the bag is considered to fail this peeling test. The ease with which seams can be separated by peeling is graduated on an AF base.

<img file="CO6541549A2_D0047.tif" />

3. Tensile Test

The tensile test is used to test the upper horizontal and lower horizontal flap seams of a bag by manually pulling both the open mesh material and the sheet materials in opposite directions in the same plane. If the open mesh material separates relatively easily from the sheet material, the bag is considered to fail in the tensile test. The average ease with which the cost

<img file="CO6541549A2_D0048.tif" />

<img file="CO6541549A2_D0049.tif" />

Ras could be separated from each bag style graduated on an AF basis.

The following bag styles were tested.

Bag Style A: Multiple Substrates Bag

Pounds with HDPE / Co-Ex, 46 ° Included Angle

In this series, constructed bags were tested as described above in relation to FIGS. 28-31 and 32-35. The bags were sized to store 5 li10 bras (2.2 kg) of items. The open mesh material of the mesh tape was an ultra-mesh material in the form of a nonwoven fabric generally of the type illustrated in FIGS. 1-3 above, which has a mass per unit area of ​​17 g / m² and which consists of two layers of warp of a coextruded filament flanking two layers of weft of high density polyethylene (HDPE). The diamonds formed by the weft filaments extended at included angles of about 46 ° in relation to the vertical or transverse direction of the machine. Each weft filament was formed from an 80 micrometer thick three layer tape having a 50 micrometer thick HDPE layer interposed between two 15 micrometer thick layers of a LLDPE linear low density polyethylene. The tape was stretched at a 6: 1 ratio to form the filaments that were incorporated into the tissue, after which the composite filament had a thickness of about 0.03 mm and a width of 1.2 mm. The warp filaments of each layer were separated 8 mm. The fabric was an alternating fabric in which the warp filaments of the lower layer were spaced about halfway between the warp filaments of the upper layer, leading to a warp filament that is spaced in the fabric about 4 mm . Each filament of the weft layer had a thickness of about 0.04 mm, and a width of about 1.5 mm.

The film used to obtain these sheet sections of the bag was a multilayer coextruded film of the type described above in relation to FIGS. 28-31 and 32-35. It had a thickness of 1.75 thousand. (0.044 mm).

Bag Style B: 5 Pound Multiple Substrate Bag with HDPE / Co-Ex, 46 ° Included Angle with Extra Strands

This bag style was identical to Style A, except for the fact that extra warp filaments were included in the ultramalla material in the area of ​​the upper and lower horizontal seams as explained above in relation to FIGS. 35 and 36. As is standard practice, the film material on the side of the bag sheet and the reinforcing tape was thinner than the corresponding film section in a smaller bag, which is 1.35 thousand thick. . (0.034 mm).

Bag Style C: 10-Pound Multi-Substrate Bag with HDPE / Co-Ex, 46 ° Included Angle with Extra Strands

This bag style was identical to Style B but was a larger bag, designed to hold 10 pounds (4.5 kg) of items.

Bag Style D: Multiple Substrate Bag

<img file="CO6541549A2_D0050.tif" />

Pounds with HDPE / Co-Ex, 34 ° Included Angle

This style of bag was identical to Style A, except for the fact that the included angle of the diamonds formed by the weft filaments that cross the ultramalla material was 34 ° in relation to the transverse direction of the machine. The mesh fabric had a mass per unit area of ​​20 g / m². The warp filaments of the mesh fabric had a uniform spacing along the length of the mesh tape.

Bag Style E: 5-Pound Multi-Substrate Bag with HDPE / Co-Ex, 34 ° Included Angle with Extra Strands

This style of bag was identical to Style D (that is, the included angle of the diamonds formed by the weft filaments that cross the ultramalla material was 34 ° in relation to the transverse direction of the machine), except for the fact that extra warp filaments were included in the open mesh fabric in the area of ​​the upper and lower horizontal seams as explained above in relation to FIGS. 37 and 38. The ultramalla material had a mass per unit area of ​​20 g / m².

Bag Style F: 10 Pound Multiple Substrate Bag with HDPE / Co-Ex, 34 ° Included Angle with Extra Strands

This style of bag of multiple substrates was identical to Bag Style E, except for the fact that the bags were larger bags, constructed with thicker film in the sections of the film, and were designed to contain 10 pounds (4, 5 kg) of items.

w

Bag Style G: 5 Pound Multiple Substrate Bag with Co-Ex / Co-Ex, 34 ° Included Angle

This bag is identical to the previous Bag Style A, except for the fact that both the warp and weft filaments of the ultramalla material of the multi-substrate bag were formed of a coextruded multilayer material as described above in relation to with FIGS. 4-7. Both warp filaments and weft filaments were coextruded three layer filaments of the type described d in relation to Bag Style D. The ultramalla material had a mass per unit area of ​​19.5 g / m². The warp filaments were separated from each other 4 mm along the entire length of the mesh tape, when viewed through the depth of the fabric.

The peel test, the tensile test, and the drop test of all these bags are summarized in Table 10 below:

TABLE 10: RESULTS OF THE FALL, FELT TESTS,

AND TRACTION

<td rowspan="2">Style from bag</td><td rowspan="2">Bag Size</td><td rowspan="2">Mesh Type</td><td colspan="2">Upper and Lower Closures</td><td colspan="2">Lateral Closures</td><td rowspan="2">Caldas Socks until the Failure</td><td rowspan="2">Mass of Mesh (g / m²)</td>

<td>Peeling Test</td><td>Traction test</td><td>Test from Bare</td><td>Test from Calda</td>

<td>TO</td><td>10 pounds</td><td>HDPE / Co-Ex, 46 ° Included Angle</td><td>B</td><td>B</td><td>B</td><td>B</td><td> 12,8</td><td> 17</td>

<td>B</td><td>5 pounds</td><td>HDPE / Co-Ex, Included 46 ° Angle with Extra Filaments</td><td>B</td><td>B</td><td>B</td><td>B</td><td> 23,3</td><td> 17</td>

<td>C</td><td>10 pounds</td><td>HDPE / Co-Ex, Included 46 ° Angle with Extra Filaments</td><td>B</td><td>B</td><td>B</td><td>B</td><td> 21,9</td><td> 17</td>

<td>D</td><td>5 pounds</td><td>HDPE / Co-Ex, 34 ° Included Angle</td><td>C +</td><td>B-</td><td>B</td><td>TO</td><td> 25,0</td><td> 20</td>

<img file="CO6541549A2_D0051.tif" />

<td>AND</td><td>5 pounds</td><td>HDPE / Co-Ex, 34 ° Included Angle with Extra Filaments</td><td>B</td><td>B</td><td>TO</td><td>TO</td><td> 23, 9</td><td> 20</td>

<td>F</td><td>10 pounds</td><td>HDPE / Co-Ex, 34 ° Included Angle with Extra Filaments</td><td>TO</td><td>TO</td><td>TO</td><td>TO</td><td> 21,5</td><td> 20</td>

<td>G</td><td>5 pounds</td><td>Co-Ex / Co-Ex, 34 'Included Angle</td><td>B +</td><td>B + -</td><td>TO</td><td>TO</td><td> 24,3</td><td> 19.5</td>

The tests confirmed that acceptable sewing properties were obtained for all the bags listed. Particularly good results were obtained with Bag Styles B, C, E, and F, all of which had extra warp filaments in the upper and lower horizontal seam areas of the ultramalla material. It seems that together the best results were achieved with Bag Styles E and F, whose open mesh material of both had extra warp filaments in the areas of the upper and lower horizontal seams and an included angle of 34 ° of the filaments frame weights as explained above in relation to FIGS. 36 and 37.

Traction Test Results

Seams of various bag styles were also tested in a tensile apparatus in order to obtain a more quantifiable test of seam strength. The tensile test apparatus consisted of two pliers separated 3 inches. Each bag to be tested was cut into three two-inch wide ribbons containing the upper horizontal seam, the lower horizontal seam, and one of the side seams, respectively. In each trial, one of the tapes was fastened in the tongs at their opposite ends. The tongs were then separated by traction at a constant speed.

<img file="CO6541549A2_D0052.tif" />

<img file="CO6541549A2_D0053.tif" />

<img file="CO6541549A2_D0054.tif" />

24 inches / min. (61 cm / min.) To mimic the efforts imposed on a bag during a rigorous filling process. The pliers were pulled apart by traction, while monitoring the load on the bag, until the seam failed. The seam failure was as defined by a 20% drop in the applied load. The maximum force applied before sewing failure was recorded.

The results of these tests are summarized in Table 11 below:

TABLE 11: RESULTS OF THE TRACTION TEST

<td>Style from Bag general</td><td>Bag Description</td><td>Bag Size (LBS)</td><td>Max force Side Seam (N)</td><td>Max Force of the Upper Horizontal Seam (N)</td><td>Max Force of the Lower Seam (N)</td><td>Mesh Mass of the Lower Horizontal Seam / Area (g / m2)</td>

<td>Bl</td><td>HDPE / Co-Ex, Included 46 ° Angle with Extra Warp Strands</td><td> 5</td><td> 20, 6</td><td> 34,0</td><td> 21,7</td><td> 17,0</td>

<td>B2</td><td>HDPE / Co-Ex, Included 46 ° Angle with Extra Warp Strands (Retest)</td><td> 5</td><td> 21, 6</td><td> 38,7</td><td> 27, 1</td><td> 17,0</td>

<td>D</td><td>HDPE / Co-Ex, Included Angle of 3. 4"</td><td> 5</td><td> 20,7</td><td> 36,4</td><td> 29, 1</td><td> 20,0</td>

<td>He</td><td>HDPE / Co-Ex, Included Angle of 34 ° with Extra Warp Strands</td><td> 5</td><td> 28,3</td><td> 36, 9</td><td> 25, 6</td><td> 20,0</td>

<td>E2</td><td>HDPE / Co-Ex, Included Angle of 34 ° with Extra Warp Strands (Retest)</td><td> 5</td><td> 21, 6</td><td> 37,8</td><td> 24,0</td><td> 20,0</td>

<td>G</td><td>Co-Ex / Co-Ex, Included angle of 46 °</td><td> 5</td><td> 25, 1</td><td> 33,1</td><td> 25,2</td><td> 19, 5</td>

X

It should be noted that not all bag styles referenced in Table 11 were strictly identical to any corresponding bag style summarized in Table 10. For example, the ultra-mesh material of the bag style labeled HDPE / Co-Ex, Included Angle 46 ° with Extra Warp Filaments (Bl bag style) had extra warp filaments in the lower horizontal seam installed in a stacked arrangement with the remaining filaments instead of an alternating arrangement as described above in relation to Bag Style B. Similarly, the extra warp filaments in the ultramalla material of the bags labeled HDPE / Co-Ex, 34 ° Included Angle with Extra Warp Filaments (bag style E) had the extra warp filaments in the horizontal seam bottom installed in a stacked arrangement with the remaining filaments instead of an alternating arrangement as described above in relation to Bag Style E.

The tensile test was sufficiently correlated with the drop test, the peel test, and the tensile test to confirm that the upper and lower horizontal seams and the side seams of all new bags. They are more than strong enough for their initial purpose. Still, all the new bags enjoyed the benefits that result from the combination of the high dimensional stability, low mass, and high mass resistance ratio of the ultra-mesh material described herein. These benefits include a reduced carbon footprint, a reduced volume for storage and transport, and enhanced ventilation and visibility.

<img file="CO6541549A2_D0055.tif" />

The greater dimensional stability provided by the ultramalla material of the 2,034 tape, coupled with the highest mass resistance ratio, contributes to the possibility of forming bags having a seam strength that is in proportion to or even exceeds that of the bags of multiple previous substrates, while substantially reducing the carbon footprint of the bags both in manufacturing and in the consumption of raw materials. It also reduces the weight and volume of the bag. The reduced weight reduces transport costs, also reducing the carbon footprint of the bag.

The test has confirmed that the reduced volume allows them to be stored in a given volume and significantly more bags of multiple substrates are transported than comparable prior art bags. The trial compared new 5-pound style bags, constructed in accordance with the present description, with 5-pound bags that were identical to those bags except that they use CLAF® grade MS as the open mesh material, while the bags again style used the ultramalla material A as the mesh portion of the bag. Three bundles of each type of bag were tested, each bundle containing 250 bags. In each test, the initial or uncompressed height of the stack was measured. A force of 27.1 N was then applied to each stack evenly along the length of the stack, and the height was again measured. The 27.1 N force was designed to mimic the compressive force im30 typically placed on a bunch of bags when stored in boxes. A total force of 42.3 iN was then applied uniformly along the length of each bundle, and the height was again measured. The averages of the three series of trials were then calculated for both styles of bags, and recorded. The results of these tests are summarized in Table 12 below.

TABLE 12: STABILITY OF MULTIPLE SUBSTRATE BAGS

<td>Mesh Type</td><td>Height Before Be Compressed (cm)</td><td>Number of Bags / cm</td><td>Compressed Height @ 27.1 N (cm)</td><td>Number of Bags / cm</td><td>Compressed Height @ 42.3 N (cm)</td><td>Number of Bags / cm</td>

<td>CLAF® grade MS</td><td> 14,0</td><td> 17,9</td><td> 7,0</td><td> 35,7</td><td> 6,4</td><td> 39,1</td>

<td>Ultramalla A</td><td> 12,7</td><td> 19,7</td><td> 6, 4</td><td> 39,1</td><td> 5,3</td><td> 47,2</td>

Table 12 confirms that, when compressed using a force of a magnitude typically applied to the bags when filled in boxes, they can be stored and transported in a given volume around 10% -40% more new style bags than comparable prior art bags constructed using CLAF® grade MS as the open mesh material. Multi-substrate bags are typically transported in boxes containing four bundles in each box. The improved stackability of the bags produced according to the description allows a fifth hand20 bags of bags to be added to each box, reducing transport costs and the carbon footprint of the bags.

The relatively open nature of mesh fabric also substantially improves ventilation and visibility of stored items.

Many changes and modifications could be made to substrates, bags, and production systems and processes.

<img file="CO6541549A2_D0056.tif" />

The characteristics described here without separating from the spirit of the present invention. To the extent that they may not be apparent from the foregoing, the scope of these variations will be apparent from the appended claims.