Bags made of open mesh material

Description

BACKGROUND OF THE INVENTION

Field of the Invention

[0001] The invention relates to a bag made of a net material, and more particularly it relates to a bag made of a net material made of fibers, at least some of which are composite fibers thermally bonded to other fibers at at least some crossing points. The invention further relates to various types of bags made of such material and to methods of making these bags.

Description of the state of the art

[0002] Synthetic netting materials are used in many applications, including bags, sludge barriers and other barriers, bale wrappers and screens. These materials are formed in a mesh pattern. Traditional mesh materials take the form of crossing threads or fibers that are woven or knitted together without the fibers sticking together at their crossing points. Recently, synthetic cross-laminated films have been introduced in which adjacent layers of cut and biaxially stretched sheets are attached to each other by thermal bonding rather than weaving or knitting. Many of the prior art mesh materials are not dimensionally stable. 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 are also relatively weak. Other materials offer better dimensional stability but are relatively heavy per unit area. These prior art materials are also relatively expensive to produce. The scope of their applications is also limited due to possible changes in material properties.

SUMMARY OF THE INVENTION

[0003] According to the invention, the mesh material comprises fibers that intersect with each other, at least some of the fibers are composite fibers having a relatively high melting point support portion and a relatively low melting point bonding portion, the bonding portion of each composite fiber is thermally bonded to other fibers at at least some of the intersecting points. The mesh material has a grammage of less than 30 gsm². In other embodiments, the mesh material has a basis weight of less than 25 gsm², less than 20 g / m², and even less than 15 g / m².

The netting material can extend in the machine and cross machine directions and has a strength to weight ratio in at least one of the machine and cross machine directions of at least 2.67 N / (g / m²), where strength is measured in accordance with ASTM D 5034. In other implementations, the strength-to-weight ratio may exceed 3.30 N / (g / m²) or even 4.45 N / (g / m²).

The mesh material may have an elongation percentage in at least one of the machine and cross-machine directions of no more than about 50%, where the elongation percentage is measured in accordance with ASTM D 5034. In other embodiments, the elongation at break may not be greater than about 50%. than 40% or not more than 30%.

ΕΡ2486178Β1

[0006] The mesh material may have a basis weight of less than 20 g / m2² and a puncture strength of at least 80 kPa, where the puncture strength is measured according to ASTM standard D 3786. In other embodiments, the puncture strength may exceed 100 kPa or even 150 kPa.

[0007] The netting material may have a tear strength at intersection points greater than 10N, where the tear strength is defined as the material's breaking force. In other embodiments, the breaking strength may be greater than 15N and even greater than 20N.

[0008] While the desired characteristics of the mesh material in terms of basis weight, strength to weight ratio, percent elongation etc. may vary depending on the intended end use of the material, the material of the present invention has a low basis weight and a high strength to weight ratio while maintaining high dimensional stability. This low grammage and high strength-to-weight ratio of the material reduces the carbon footprint associated with the manufacture, transportation and disposal of products made of the material, such as fruit and vegetable bags, because the products require less raw materials and take up less volume. Thus, they require less energy to produce and handle them than products made from traditional materials.

[0009] In one configuration, the fabric is a knitted fabric that includes at least two layers of weft yarns that may be bounded on one or both sides by a layer of the warp yarns. The weft fibers cross each other at an acute angle to form a general diamond pattern. The warp fibers extend at an acute angle with respect to the crossing fibers and parallel to each other and may extend parallel to the machine direction. The warp fibers and possibly also weft fibers are composite fibers that can be thermally bonded. One or both surfaces of the knitted fabric may be provided with additional layers such as additional warp and / or weft layers, a drawstring or other closing mechanism, a structure such as a label, and / or one or more laminating or reinforcement sheets. In a variant of this configuration, both layers of the warp yarns may be omitted, so that the knitted fabric is formed of crossing weft yarns.

[0010] These knitted fabrics can be made at least in part into a plurality of articles, including sludge settlers, light barriers, and bags for storing fruit and vegetable products and other items. Such bags include L-seam bags, form fill and seal bags, and multi-substrate bags such as HALF AND HALF® bags.

[0011] In the case of an L-seam bag, a mesh material having at least one of the characteristics described above may be formed to include a closed end, an open end, at least one side seam on its side, and a seam at its closed end. The side and end seams may be formed by sewing to form an "L-seam bag". The open end may include a textured portion. The textured portion, if present, may include a strip that is bonded to the knitted fabric or a textured fiber disposed around the open end.

The L-seam bag has some or all of the L-seam bag characteristics discussed above can be sufficiently thin and compressible such that when multiple bags are stacked and subjected to a force of 267 N, the stack comprises at least 25 bags / cm. . In other embodiments, the stack contains more than 30 bags / cm and even more than 35 bags / cm. The invention relates to a so-called "form, fill and seal" bag. The bag according to this aspect of the invention has first and second opposing sides each formed at least at

ΕΡ2486178Β1 parts of sheet material strip and at least part of mesh material. For example, the sheet material may be a film made at least in part from a thermoplastic film and extending longitudinally from at least one end of the bag. An end seam extends through one end of the bag and connects the first and second webs to at least one layer of mesh material therebetween. The end seam shall be made of a joint having a strength of at least 2.5 N. The form, fill and seal bag may have upper and lower ends, at least the lower end being closed. A body extends between the upper and lower ends, defining an interior volume that contains the goods. The body of the filled bag is at least generally polygonal in cross-sectional shape along at least most of its length. The body has at least two opposite sides formed of a mesh material having a grammage of not more than 30 g / m2². The bag has an initial height measured from the bottom end to the top end after the bottom end has been welded to form the body but before the goods are placed in the bag and the top end is welded. The bag further has a final height which is measured after the goods have been placed in the bag and the bag has been placed on a horizontal surface and left unsupported from above. The end height of the bag is at least 35% of its original height.

[0013] In accordance with another aspect of the invention, there is disclosed a method of forming an end seam on a bag such as a "form, fill and seal" bag. The method comprises pressing the opposite sides of the bag together under the influence of heat and pressure at a temperature of less than 149 ° C and a residence time of less than 0.5 seconds, and producing a seam having a seam strength of at least 2.5 N. The bag comprises at least two layers of sheet material and at least one layer of mesh material sandwiched between the layers of sheet material. The seam may be formed from a lap weld.

[0014] In accordance with yet another aspect of the invention, the multisubstrate bag has a first sidewall formed at least in large part from a strip of synthetic mesh material and a second sidewall formed at least in a significant part from sheet material. Opposite side edges of the first and second sidewalls are thermally bonded to each other by vertical seams, and the lower edge of the mesh material strip is thermally bonded to the film material to form the bottom horizontal seam. A reinforcing strip of sheet material may extend along the top edge of the first side wall of the bag.

[0015] The netting material may extend in the cross machine and machine directions and may have a basis weight of not more than 30 g / m2.² and a strength-to-weight ratio of at least 2.67 / (g / m²).

[0016] The increased strength to weight ratio and the resulting reduced weight of the bag also significantly reduces the carbon footprint of the multi-substrate bag. The multisubstrate bag is also relatively thin and compressed on, allowing for the storage and transport of much more bags in a given volume. In fact, the bag is so thin and compressible that when multiple bags are stacked and subjected to a compression force of 27.1 N, the stack contains at least 36.5 bags / cm.

[0017] Seam strength can be improved by configuring the mesh belt of the multisubstrate bag to have an increased surface area in the area of ​​overlapping of the film strips and the mesh belt. Increased surface area can be achieved by providing additional threads or fibers in the mesh material in the seams, thus increasing the surface area available for bonding.

[0018] These and other features and advantages of the invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings. It should be understood, however, that the detailed description and drawings indicating preferred embodiments of the present invention are given by way of title only

ΕΡ2486178Β1 illustrative, not limitative. Many changes and modifications can be made within the scope of the present invention without departing from the spirit of the present invention, and the invention includes all such modifications.

These and other features and advantages of the invention will become apparent to those skilled in the art from the following detailed description and the accompanying drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be madę within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings, in which like reference numbers represent like parts, and in which:

FIG. 1 is a top plan view of a cross section of a mesh material constructed in accordance with a first preferred embodiment of the invention;

FIG. 2 is a top plan view of a section generally taken along line II-II of FIG. 1;

FIG. 3 is a side view generally taken along the line III-III of FIG. 1;

FIG. 4 is a plan view of a mesh material constructed in accordance with the second preferred embodiment;

FIG. 4A is a top view of a mesh material constituting a variant of the material illustrated in FIG. 4;

FIG. 5 is a side cross-sectional view of a fiber used in the material of FIG. 4;

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

FIG. 7 is a cross-sectional view of a material generally taken along line VI-VII in FIG. 6;

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

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

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

FIG. 11 is a front view of an alternate other embodiment of a textured portion suitable for use with the bag of FIG. 8;

FIG. 12 is a perspective view of an alternative embodiment of a bag;

FIG. 13 is a perspective view of an alternative embodiment of a bag;

ΕΡ2486178Β1

FIG. 14 is a front view of an alternative strand embodiment suitable for use with the bag of FIG. 13;

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

FIG. 16 is a perspective view of a form-fill-seal multisubstrate bag made at least in part of mesh material;

FIG. 17 is a front longitudinal view of the bag of FIG. 16;

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

FIG. 19 is a cross-sectional view of the bag along line 19-19 in FIG. 17;

FIG. 20 is a cross-sectional view of the bag along line 20-20 in FIG. 17;

FIG. 21 is a cross-sectional view of the bag taken generally along line 21-21 in FIG.17;

FIG. 22 is a schematic longitudinal side view of a vertical form-fill-seal machine that may be used to make the bags of FIG. 16-21;

FIG. 23 is a perspective view showing in more detail a portion of the vertical form-fill-seal machine of FIG. 22;

FIG. 24 is a perspective view of a substrate that can be formed into the bags of FIG. 16-21 using the form-fill-seal machine of FIG. 22 and FIG. 23;

FIG. 25 is a perspective view of a form-fill-seal bag constructed in accordance with 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;

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

FIG. 28 is a perspective view of a multi-substrate bag constructed in accordance with another embodiment of the present invention;

FIG. 29 is a front longitudinal view of the bag of FIG. 28;

FIG. 30 is a rear longitudinal view of the bag of FIG. 28;

FIG. 31 is a cross-sectional view along line 31-31 of FIG. 28;

ΕΡ2486178Β1

FIG. 31A is a side cross-sectional view of another alternative bag construction of FIG. 28-31;

FIG. 31B is a side cross-sectional view of another alternate bag construction of FIG. 28-31;

FIG. 31C is a side cross-sectional view of another alternative bag construction of FIG. 28-31;

FIG. 32 is a top view along line 32-32 of FIG. 29;

FIG. 33 is a partial perspective view showing the top of the bag of FIG. 28-31;

FIG. 34 is a partial longitudinal front view of FIG. 29;

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

FIG. 36 is a rear longitudinal view of a bag constructed in accordance with another embodiment of the present invention;

FIG. 37 is a partial longitudinal front view of the portion of FIG. 36;

FIG. 38 is a front longitudinal view of a bag constructed in accordance with another embodiment of the present invention;

FIG. 39 is a partial longitudinal front view of FIG. 38.

DETAILED DESCRIPTION OF ADVANTAGE EQUIPMENT

[0020] Several non-limiting embodiments of a netting material will now be described, followed by a description of the uses of such material as bags of various styles.

1. Mesh material

[0021] As noted above, a mesh material constructed in accordance with the present disclosure includes fibers that intersect with each other and that are thermally bonded at at least a portion of their intersection points to form a lightweight, strong, dimensionally stable mesh material. Possible materials include, but are not limited to, woven fabrics in which the fibers intersect by interlacing above and below each other, knitted fabrics in which the fibers intersect by looping around one another, and non-woven fabrics in which the fibers intersect by layering. one on top of the other in a cross pattern. "Intersecting" as used herein means that the intersecting fibers are not parallel to each other and are contacting each other at one or more locations. At least some of the fibers may contact and even be bonded to other fibers without intersecting with other fibers. However, fibers can also contact other fibers without being cut and / or bonded. For example, some of the fibers may intersect with other fibers by being collinear with and resting on top of still other fibers, such as the "stacked" warp yarns described below in connection with FIG. 1 - 3. In this embodiment, the warp yarns of the upper ply intersect with the weft yarns by being collinear with and

ΕΡ2486178Β1 resting on top of the underlying weft fibers of the bottom layer. Moreover, at least some of the fibers may intersect without being thermally bonded to each other at their crossing points, such as in the case of the weft fibers described below in connection with FIG. 1 -3.

[0022] As used herein, the term "fiber" should be understood as a strand of material and should be considered synonymous with "tape", "web", "yarn" or "thread". To provide a frame of reference, the terms "warp yarns" and "weft yarns" will be used to describe the crossing fibers. Typically, but not necessarily, the warp yarns will extend at least generally in the "machine direction". It should be understood that these terms are used as a frame of reference only and do not require the material to be manufactured in any particular manner or to 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.

[0023] Some or all of the fibers are "composite fibers". The term "composite fiber" as used herein refers to a fiber formed from a composite material having a high melting point "support" portion and a relatively low melting point "bonding" portion. The support portion is also preferably, but not necessarily, higher in density than the bonding portion. It forms the structural element of the fiber. These composite fibers can be made of a variety of materials, such as a monolayer material formed from a blend of low melting, high melting point materials. They can also be made of laminated material layers or co-extruded material layers. Composite fibers made of co-extruded materials can be formed, for example, of a so-called core and a sheath material in which a core with a relatively high melting point is surrounded by at least one layer of a sheath with a relatively low melting point. A single core may be contained in each of the sheaths. Alternatively, multiple cores may be included in each sheath. The sheathed cores may be spaced apart or abutting each other, either lying side to side or forming a braid or otherwise interlacing. Alternatively, the co-extruded materials can be formed from a relatively high melting point layer having a relatively low melting point layer disposed on one or both sides. The term "melting point" as used herein refers to the temperature at which a material can begin to bond to another material.

[0024] Composite fibers may be formed by (i) mixing the materials in a monolayer or monofilament, (ii) laminating the materials, or (iii) co-extruding the materials. Many permutations of low melting point materials and high melting point materials can be used to make these composite fibers. Possible material combinations include high density polyethylene (HDPE) or low density polyethylene (MDPE) as the support part and low density polyethylene (LDPE) or linear low density polyethylene (LLDPE) as the bonding part. These materials can be used alone or mixed or otherwise combined with other materials. Other possible material combinations include the use of heat-bendable polypropylene as one or more support and bonding parts. In addition, other materials (e.g., biodegradable materials such as cellulosic materials or starch materials) may be used for all or part of one or both of the fragments. The material of the bonding / bonding part has a lower melting point or begins to melt at a lower temperature than the material of the support / supports. The resultant composite fibers can be heated to a temperature at which the bonding portion (s) will bond sufficiently to adjacent fibers without significantly affecting the dimensional and structural integrity of the bonding / bonding portion.

[0025] Turning now to FIG. 1-3, a first embodiment of a mesh material made of intersecting fibers of the type described above is illustrated. Material including

ΕΡ2486178Β1 is actually a non-woven fabric made of two mutually intersecting groups of elongated weft fibers 1,2 surrounded by lower 3 and upper warp layers, respectively 4. The warp layers 3 and 4 are made up of respective warp layers 5 and 6, respectively 2 cross each other at an acute angle to form a generally diamond-shaped pattern. The warp fibers 5 and 6 extend at an acute angle with respect to the crossing fibers and parallel to each other. In the embodiment illustrated, they extend in the machine direction, but may also extend in other directions.

[0026] In the embodiment discussed, the weft fibers 1, 2 of the fabric are not composite fibers. As such, the weft fibers 1, 2 have the capacity to bond together only to a small extent, if at all. The weft fibers 1, 2 are secured in their relative position by lower and upper cover plies or warp plies 3, 4, each formed of a plurality of spaced apart parallel elongated warp yarns 5 and 6, respectively. As shown in FIG. 1, the yarns 5 of the lower warp layer 3 and the yarns 6 of the upper warp layer 4 are aligned with each other so that the weft yarns 1, 2 are fastened between the interconnected strips of the layer 5, 6 without having to join the weft yarns 1, 2 together in the region their crossing points. The layers are thermally bonded and pressed together after or during the laying process to fuse the layers together at their intersection points and thereby form a material.

[0027] As mentioned above, the netting material of this embodiment is a non-woven fabric made of mutually crossing small fibers, each arranged in their own plane, rather than taking the form of a knitted or woven material, where the fibers are threaded through loops or interlaced. As a result, simple constructional conditions are obtained, with the advantage that there are no loop or interlaced joints in the regions where the warp and weft yarns intersect, which would disturb the structural integrity of the material. At the intersection of the loop or interlaced connections, the fibers cross each other so that the fibers change planes. This change in the planes of the fibers in the loop or interlaced joints creates stress points in the woven or knitted fabric. In the netting material according to this embodiment, stress points are avoided as the warp and weft fibers only lie flat on each other and can have a very thin thickness, for example between 10 and 35 µm, which maximizes the tensile strength of the material. The relative positioning of the weft fibers between the warp fibers provides for heat welding of the two warp layers to one another and the warp layers to the weft layers disposed therebetween. In this way, the weft and warp yarns are tightly bonded in a non-separable manner. The heat treatment of the material also ensures that the mesh material undergoes only very low residual shrinkage and / or elongation.

[0028] To ensure that the warp yarns 3, 4 can determine the position of the weft yarns at their intersection points by thermal bonding, the warp yarns 3, 4 are composite yarns as described above. The composite fibers can be formed from any combination of the materials described above, as long as at least one part is formed from a material with a higher melting point than the other parts. In the illustrated embodiment, the fibers 5 and 6 of the warp layers 3 and 4 are composite fibers made of co-extruded film having a support layer with relatively high breaking strength and high melting point, and an adhesive layer with a relatively low melting point on at least one side of the layer. support, facing the weft fibers 1, 2. The support layer and the bonding layer of the composite fibers of the warp layers 3 and 4 of this embodiment comprises HDPE or MDPE and LDPE or LLDPE, respectively. The weft fibers 1 and 2 of this embodiment are made of a relatively high strength material having a melting point higher than that of the bonding layer of the warp yarns. Currently HDPE is preferred, but other materials such as thermally bondable polypropylene may be used. High density

The 2486178Β1 weft fiber material may or may not be coated with a lower melting point material such as LLDPE to strengthen the weld at the points of intersection with the warp layer fibers.

[0029] The desired sizes of individual fibers can vary widely, depending on several factors including the composition of the fibers and the intended use of the mesh material. For example, the warp and weft fibers may be 40-200 microns thick, and typically 60-150 microns thick. The weft fibers in the illustrated embodiment are much wider than the warp yarns, but fibers of the same or approximately the same width may be used in all plies if desired. Furthermore, the weft yarns may be narrower than the warp yarns.

[0030] While the desired characteristics of the mesh material in terms of basis weight, strength to weight ratio, percent elongation, etc. may vary depending on the intended end use of the material, the material of the present disclosure has a low basis weight and a high strength to weight ratio while maintaining and good dimensional stability. This low grammage and high strength-to-weight ratio of the material reduce the carbon footprint associated with the manufacture, transportation and disposal of products made of the material, such as fruit and vegetable bags, as the products require less raw materials and take up less volume. They therefore require less energy to produce and manipulate them than products made from traditional materials.

[0031] One example is family or "consumer" bag applications used to contain goods such as nuts, oranges, potatoes, onions, seafood (such as shrimp, shells or clams), newspapers, flower tubers, dried beans, and packaged sweets. These and other bags are used to store goods and display them at points of sale. The net material used to form at least some of these bags preferably has a basis weight of less than 30 g / m2², more preferably equal to about 25 g / m2² or less, and even more preferably in the range of about 15 g / m2² up to about 20 g / m². Its strength to weight ratio in at least one machine and cross machine direction 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 / m2²), and even more preferably greater than or equal to about 4.45 N / (g / m2²), where strength is measured in accordance with ASTM D 5034. As a measure of dimensional stability, the material preferably has a percent elongation in the machine and cross machine direction of less than or equal to about 50%, more preferably less than or equal to about 40%, and even more preferably less than or equal to about 30%, where elongation is measured according to ASTM D 5034.

[0032] The mesh material, hereinafter "material 1", which has been successfully tested in this regard, is a non-woven material formed from i) composite warp yarns made of a middle ply 50 microns thick HDPE co-extruded on the lower and upper sides with a LLDPE layer. 15 microns thick, and ii) 100% HDPE weft fibers. Using the test method of ASTM D 5034 to determine breaking strength and breaking elongation, the material was clamped between opposing jaws and stretched to the breaking point by measuring the elongation of the material and the applied force. The material was considered "broken" when it was torn and subjected to an applied force that peaked and then decreased by 20%. The applied peak force was then recorded as "breaking force". The test was repeated in the machine and cross machine directions for a statistically significant number of samples. The tests showed that the material had a grammage of 20 g / m², strength 92.6 N, and strength to weight ratio 4.63 N / (g / m²) in the machine direction. Material 1 also had a strength of 41.8 N and a strength to weight ratio of 2.09 N / (g / m)²) in the cross machine direction. It had an elongation

ΕΡ2486178Β1 percent about 42% in the machine direction and about 33% in the cross machine direction.

[0033] After thermally bonding the fibers of the layered structure of the nonwoven fabric according to this embodiment, the resulting mesh material is dimensionally stable, offers very low residual shrinkage and elongation, and can be thermally bonded to materials with similar melt index properties, such as the same or similar materials, foils, etc. The material density per unit area is determined by a number of factors, including the density and width of the individual fibers of each of the plies, the spacing between the parallel warp yarns 5 and 6 of each of the plies 3 and 4, and the slope or slope of the weft 1 and 2 yarns. as the pitch of the weft yarn increases and / or the spacing of the warp and / or weft yarns increases. As the mesh openness increases, the mesh density decreases. For a given fiber composition and size, the dimensional stability and machine direction strength of the material are at least generally proportional to the spacing between the warp yarns and is least generally proportional to the slope or slope of the weft yarn relative to the machine direction. The dimensional stability and strength of the material in the cross machine direction, on the other hand, is generally proportional to the bond strength at the intersection of the various layers and inversely proportional to the slope or slope of the weft fibers relative to the machine direction.

[0034] Turning to FIG. 4-7, a second embodiment of a mesh material made according to the disclosure is illustrated. The material according to this embodiment, like that of the first embodiment, is a non-woven material made of two mutually crossing groups of weft yarns 11, 12 which are fixed in their mutual position by thermal bonding to the lower and upper skin layers or warp layers 13, 14. . The weft fibers 11 and 12 cross each other at an acute angle to form a diamond-shaped pattern. Each of the warp plies 13 or 14 is formed of a plurality of spaced parallel yarns 15 or 16 extending in the machine direction. The fibers 15 and 16 of the warp layers are composite fibers as discussed above in connection with the first embodiment.

[0035] The material of this embodiment differs from the material of the first embodiment in that the weft yarns 11 and 12 are also composite yarns. All composite fibers 11, 12, 15 and 16 in the embodiment illustrated are made of the same composite material, but it should be understood that the fibers 11 and 12 of the weft layers may be made of a different composite material than the fibers 15, 16 of one or both of the warp layers 13. 14. The illustrated composite fibers are made of a layered co-extruded material, but may be made of, for example, a blended material, a laminated material, or a braided or braid material.

[0036] Each of the illustrated composite fibers 11, 12, 16 of this embodiment includes a triple layer of co-extruded material illustrated schematically in FIG. 5. The material has a central support layer 18 with a relatively high melting point, which is closed by the adhesion layers 19 and 21 of the material having a relatively low melting point. The layers 18, 19 and 21 can be formed of any combination of the materials described above as long as the support layer is formed from a material with a higher melting point than the bonding layer (s).

[0037] The composite weft yarns 11, 12 of this embodiment are positively bonded to both the warp yarns 15, 16 and to each other at their intersecting points. As a result of this configuration, the fibers of all material layers are bonded to each other at all points of intersection by melting and re-curing the bonding layer material as schematically illustrated in FIG. 7. Since the cross-machine strength of the material depends primarily on the overall strength

ΕΡ2486178Β1 of the welds, positive bonding of the weft fiber to the weft fiber results in a higher strength of the material in the cross-machine direction than in a material where the weft fibers are not made of a composite material (assuming that all other material characteristics, including fiber thickness, density fibers, fiber composition, etc. are the same).

[0038] The material, hereinafter referred to as "material 2" that has been successfully tested in this regard, has both warp and weft yarns formed of a 50 micron thick middle HDPE layer co-extruded on its top and bottom sides with an LLDPE layer of 15 microns thick. Material 2 has a basis weight of 20 g / m². It has a strength of 89.8 N and a strength-to-weight ratio of 4.49 N / (g / m²) in the machine direction. Material 2 also has a strength of 59.6 N and a strength-to-weight ratio of 2.98 N / (g / m)²) in the cross machine direction. It has an elongation percentage of about 40% in the machine direction and about 27% in the cross machine direction.

[0039] The material illustrated in FIG. 4-7 differs from the material illustrated in FIG. 1-3 also in that the yarns 15 of the lower warp layer are offset from the yarns 16 of the upper warp layer. This arrangement provides more points of intersection in a given area of ​​material for the bonding, although less material is available for the bond at each given point of intersection. Of course, the lower warp yarns 15 may also be aligned with the upper warp yarns 16, as discussed above in connection with the first embodiment.

[0040] At least some of the warp yarns in one and possibly both layers 13 and 14 may extend non-linearly instead of linearly. An example of this variant is illustrated in Fig. 4A, where some of the fibers 16 'in the upper warp layer 13 are arranged in a generally sinusoidal form. Other repetitive or non-repeating waveform forms are also possible. For example, one of the fibers 16 "is shown as a sinusoidal form with a waveform that is 180 degrees offset from the adjacent nonlinear fiber 16 '. These and other variants can be provided in the same or different material.

[0041] Many changes and modifications can be made to the mesh materials of the invention. For example, as briefly mentioned above, one or more of the warp plies of the nonwoven material of FIG. 1-3 or the nonwoven material of FIG. 4-7 can be omitted, which results in a two or three layer material. Moreover, one or more auxiliary materials or plies may be provided on the outside and / or inside of one or both of the warp layers and even in the weft layer. For example, a structure such as a label, one or more reinforcement sheets, or one or more additional carcass plies may be provided on the surface of one or both of the carcass plies. A closing device, such as a drawstring, may also be provided in the weft layers. Moreover, while the discussion focuses primarily on nonwoven fabrics, the disclosure also applies to knitted fabrics and fabrics in which at least some of the intersecting fibers are thermally bonded to each other at at least some of their intersecting points. Mesh materials falling within the scope of this disclosure will hereinafter be referred to as "ultra-mesh materials" as the short designation of these materials.

Characteristics of the mesh material

[0042] Specific examples of the mesh materials of the type disclosed above were tested. Four samples were tested, grouped as follows:

Sample 1:

ΕΡ2486178Β1

The ultra-mesh material formed from a nonwoven fabric of the type generally illustrated above in FIG. 4 and 5-7. The nonwoven fabric consisted of two layers of co-extruded fiber warp surrounding two layers of high-density polyethylene (HDPE) weft. The weft fibers extended at angles of about 30 ° from the cross machine direction (a is shown below in FIGS. 34, 37 and 39). Each individual fiber thus extended at an angle of 15 ° to the cross machine direction. Each weft fiber was formed from an 80 micron thick three layer web having a 50 micron thick HDPE layer sandwiched between two 15 micron thick LLDPE linear low density polyethylene layers. The web was stretched 6: 1 to form fibers that were incorporated into the fabric, whereupon the composite fiber was about 0.03 mm thick and about 1.2 mm wide. The fiber spacing of the warp of each of the plies was 8 mm. The fabric was an alternating fabric in which the warp yarns of the underlayer were approximately halfway between the topsheet yarns, leading to a warp yarn in the material of about 4mm. Each warp fiber was about 0.04 mm thick and about 1.5 mm wide.

Sample 2:

The same ultra-mesh material as Sample 1 except that the weft fibers had an included angle of approximately 36 ⁰ with respect to the cross machine direction.

Sample 3:

The same ultra-mesh material as Sample 1 except that the weft fibers had an included angle of about 40 ⁰ with respect to the cross machine direction.

Sample 4:

The same ultra-mesh material as Sample 1, except that the weft fibers had an included angle of about 46 ⁰ with respect to the cross machine direction.

[0043] The test results are summarized in Table 1 below:

TABLE 1: CHARACTERISTICS OF THE MESH MATERIAL

<td>Feature</td><td colspan="4">A sample #</td>

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

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

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

<td>Strength to weight factor (machine direction - N / (g / m²))</td><td> 4,25</td><td> 4,37</td><td> 3,50</td><td> 4,00</td>

<td>Breaking Strength (Cross Machine Direction - N) (ASTM D 5034 Grip Method)</td><td> 87</td><td> 41</td><td> 69</td><td> 52</td>

ΕΡ2486178Β1

<td>Feature</td><td colspan="4">A sample #</td>

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

<td>Strength to weight factor (transverse to machine direction - N / (g / m²))</td><td> 4,35</td><td> 2,15</td><td> 3,83</td><td> 3,06</td>

<td>Puncture resistance (kPa) (ASTM D 3786)</td><td> 200</td><td> 172</td><td> 131</td><td> 96</td>

<td>Elongation at Break (Machine Direction -%) (ASTM D 5034)</td><td> 51,0</td><td> 51,8</td><td> 57,1</td><td> 57,1</td>

<td>Elongation at Break (Cross Machine Direction -%) (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 Direction ASTM D 1894)</td><td> 0,562</td><td> 0,366</td><td> 0,317</td><td> 0,478</td>

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

<td>Static Friction Coefficient (Cross Machine Direction - ASTM D 1894)</td><td> 1,300</td><td> 1,130</td><td> 1,390</td><td> 1,220</td>

[0044] The coefficient of friction tests were carried out according to ASTM D 1894. The coefficients of friction were measured by sliding a sled, having its bottom surface coated with a rubber sponge, over a flat surface with the test material.

[0045] The ultra-mesh material was also tested for "stackable". "Stackability" herein refers to the number of strips of material contained in a pile of a given height when the pile is subjected to a given force. The stack may be linear with the discrete strips stacked one on top of the other, as is typical when goods are stored in a box or other container. Alternatively, the stack may be tubular as is typical when material is rolled around itself to form a roll. It can also be linear, but formed from a continuous sheet folded in a so-called Z-pattern. Stacking is an important feature for many materials because, inter alia, materials or products made of at least some of them need to be transported and stored. With all other parameters being the same, it is desirable to be able to contain more materials or products in a pile of a given depth, so as to increase the number of materials or products that can be transported and stored in a given volume, thus reducing the storage space and furthermore reducing the carbon footprint of materials or products in relation to shipping costs.

[0046] In this test, 250 strips of ultra-mesh material were stacked and the initial height of the stack was measured. The ultra-mesh material was of the type suitable for use with bags and was subjected to many of the tests discussed herein. For the sake of brevity it will be referred to herein as "ultramesh A" material. The ultra-mesh material A is a nonwoven fabric of the type generally illustrated in FIG. 1-3. The material has a density of 20 g / m² and consists of two layers of co-extruded fiber warp surrounding the two layers of high density polyethylene (HDPE) weft. The warp fibers extend parallel to the machine direction. The weft fibers extend at an angle

ΕΡ2486178Β1 contained at approximately 36 ° with respect to the transverse machine direction. Each weft fiber is formed of an 80 micron thick three-layer web having a 50 micron thick HDPE layer sandwiched between two 15 micron thick linear low density polyethylene (LLDPE) layers. The web was stretched 6: 1 to form fibers that were incorporated into the fabric, whereupon the composite fiber was about 0.03 mm thick and about 1.2 mm wide. The warp fibers of each of the plies are spaced 8 mm apart. Each fiber of the weft layer is about 0.02 mm thick and about 1.5 mm wide.

[0047] A force of 27.1 Ni was then applied uniformly to each stack along the length of the stack and the height was again measured. A force of 27.1 N is designed to mimic the force typically applied to stacks of goods during box packing. A total force of 42.3 N was then applied uniformly along the length of each stack to each stack and the height was measured again. The results of these tests are summarized in Table 2 below:

TABLE 2: ULTRA-MESH MATERIAL FLEXIBILITY TEST RESULTS

<td>Height before compression (cm)</td><td>Number of belts / cm</td><td>Height after Compression @ 27.1 N (cm)</td><td>Number of belts / cm</td><td>Height after Compression @ 42.3 N (cm)</td><td>Number of belts / 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>

[0048] Another essential feature of materials formed by intersecting fibers or other structures that intersect is the strength imparted to the materials by bonding at the points of intersection. Tests for "bond strength" were carried out to measure the tear or tear strength of ultra-mesh A material at intersection points and to compare the observed strength to that between the cross-laminated cross-laminated cut and tensile film forming the material that is commercially sold under the 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.

[0049] For each test, a rectangular strip of test material 5.1 cm wide by 20.3 cm long was prepared with a cross machine direction portion extending along the length of the specimen and a machine direction portion extending in width. The tested samples of Ultra-mesh A material thus had their warp yarns stretching across the width of the sample. Each test sample was clamped between two vertically spaced jaws. The upper end of the test strip was attached to the upper jaw by engaging the carcass structure on six evenly spaced hooks that extended downward from the upper jaw and which engage the horizontally extending portion of the material. In the case of Ultra-mesh A, the hooks were caught on one of the warp yarns. The lower end of the strip was attached to the lower jaw, making sure that the material was secured in both the upper hook system and the lower jaw, while maintaining the vertical alignment of the strip with the upper and lower jaws. The jaws were then moved apart at a speed of 30.5 cm / min, the force exerted on the sample was measured. The "breaking force" or the peak force exerted on the sample, calculated as described above in connection with the discussion of "material 1", was recorded as a measure of breaking strength at intersection points or simply "weld strength". The test was repeated for a series of 10 samples each

ΕΡ2486178Β1 from tested materials. The breaking strength and standard deviation of each material were then recorded as shown in Table 3 below:

TABLE 3: TENSILE STRENGTH AT CUT POINT

<td>Mesh type</td><td>Average breaking force (N)</td><td>Standard deviation of the force at break (%)</td>

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

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

<td>Ultra-Mesh A</td><td> 25,1</td><td> 1,35</td>

[0050] Table 3 confirms that, on average, ultra-mesh A material has the tearing or tearing strength at the points of intersection of the warp and weft fibers, measured as the material breaking force, greater than 10N, greater than 15N and even greater than 20N. tear strength is well over twice as high as that of the tested CLAF® materials, even though ultra-mesh A material is lighter and more open than CLAF® materials. It is believed that comparable results would be obtained with the other ultra-mesh materials described herein.

[0051] The specific ultra-mesh materials described above, including material 1, material 2, and ultra-mesh A, as well as many other mesh materials falling within the scope of the present disclosure, can be converted into any of a wide variety of articles, such as bags, dividers, etc. sludge, bale wrappers, or screens, by any of the different converting operations. This transformation can be accomplished by creating seams by application of heat, by wrapping, by sewing, by using adhesives, or any combination thereof. Three such applications will now be described.

2. L seamed bags

[0052] The netting materials of the present disclosure, and for brevity also referred to as "ultra-mesh materials", can be converted into a so-called L-seam bag by wrapping the material around itself to form a seam at the vertical edge and sewing the material at its side and bottom edges. . The resulting bag will have an open top, one edge formed by the curl and the other edge formed by seams. These seams are typically formed by sewing, but it could also be contemplated that they could be formed by thermal bonding, using glue, or by some combination of any or all of the three and possibly other techniques. The warp plies in the material will preferably extend horizontally along the bag to maximize the strength of the side seam.

[0053] Referring now to FIG. 8, the L-seam bag 20 includes a first end 22 and an opposing second end 24. The bag 20 further includes a side seam 26 that extends between the first and second ends 22,24. The bag is formed of a mesh material, preferably one of the nonwovens described herein. above or woven or other mesh material having similar characteristics.

[0054] In the orientation depicted in FIG. 8, the first end 22 of the bag 20 is the lower end and the second end 24 of the bag 20 is the upper end. The lower end 22 is the end

ΕΡ2486178Β1 is closed, and the upper end 24 is the open end. However, the top end may be closed after filling using any suitable technique.

[0055] In the embodiment depicted, the bag 20 is formed by folding (i.e. folding over itself) the material and sewing the material at its side and bottom edges such that the bag 20 includes an internal recess 28. Bags having side and bottom seams sewn are often referred to as as seamed bags L.

[0056] A side seam 26 of a bag 20 of this embodiment is formed by sewing or sewing opposite sides of the fabric together after the fabric has been wrapped. The side 30 that is opposite the side seam 26 is the curl or kink formed by folding the material over itself. The lower end 22 includes a seam 32 that is formed by sewing a first portion of the edge of the material to an overlapping portion of the edge after the material has been folded back.

[0057] In the depicted embodiment, the material of the bag 20 is a knitted fabric oriented such that the warp yarns 15, 16 (FIGS. 1-3) are generally parallel to the seam 32 of the bottom end 22 of the bag 20. In the orientation depicted, the warp yarns 15, 16 extend. horizontally along the bag 20 to maximize the strength of the side seam 26.

[0058] Referring now to FIG. 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 which provides access to an internal cavity 28.

The upper end 24 further comprises a textured portion 38 located adjacent to the edge 34. The textured portion 38 is adapted to provide a texture that is different from that of the material of the bag 20. This distinctive texture of the textured portion 38 of the bag 20 allows the holder to identify the top end. 24 bags 20 by grip or touch.

[0060] The textured portion 38 includes a fiber 40. In one embodiment, fiber 40 has an outer diameter ranging from about 0.1 mm to about 1 mm. In another embodiment, the outer diameter of the fiber 40 ranges from about 0.1 mm to about 0.5 mm. In another embodiment, the outer diameter of the fiber 40 ranges from about 0.2 mm to about 0.3 mm. In the implementation depicted in FIG. 8 and 9, the textured portion 38 includes a plurality of fibers 40. The filament 40 is located on the outer surface of the material of the bag 20 adjacent the edge 34 such that the filament 40 does not loop or intertwine with the material. The filament 40 extends uninterruptedly around the top 34 of the bag 20.

[0061] In the embodiment depicted in FIG. 8 and 9, fiber 40 is oriented such that it is generally parallel to the fibers of the warp 15, 16 of the bag material 20. In another embodiment, the fiber 40 is generally horizontal in the pouch 20. In another embodiment, the fiber 40 is generally parallel to a plane in which has an opening 36 of the upper end 24.

[0062] In one embodiment, fiber 40 is a monofilament that is manufactured from high density polyethylene (HDPE). In another embodiment, fiber 40 is a co-extruded fiber having a carrier portion and a bonding portion. The support portion may be manufactured from materials including high density polyethylene (HDPE) or medium density polyethylene (MDPE), while the bonding portion may be manufactured from materials including low density polyethylene (LDPE) or linear low density polyethylene (LLDPE).

In one embodiment, the textured portion 38 includes a strip 42 that extends around the top end 24 of the bag 20 at a location adjacent the edge 34 of the top end 24. The strip 42 is a narrow strip of material. Belt 42 may be manufactured from a thermoplastic material, including polypropylene, low density polyethylene, coated polyester, etc. In one embodiment, the material of belt 42 is about 25 microns thick. In one of

As "2486178 "1 embodiments, the thermoplastic material of strip 42 is transparent or translucent. In another embodiment, the thermoplastic material of tape 42 is opaque.

[0064] Belt 42 defines a width W. In one embodiment, width W of belt 42 is less than or equal to about 50.8 mm. In another embodiment, width W of strip 42 is less than or equal to about 38.1 mm. In another embodiment, width W of strip 42 is less than or equal to about 25.4 mm.

[0065] In another embodiment, tape 42 is used without the fiber 40. In this embodiment, the inner surface 46 of tape 42 bonds to the warp layers 14 and the weft layers 11, 12.

[0066] The belt 42 has an outer surface 44 and an oppositely disposed inner surface 46. In the embodiments depicted in FIG. 8 and 9, the inner surface 46 adheres to the warp layers 14, the weft layers 11, 12 and the fibers 40. In one embodiment, the inner surface 46 of the tape 42 has a bonding portion which is adapted to abut the warp layers 14, weft layers 11. , 12, and fiber 40 by the application of heat and pressure.

[0067] Referring now to FIG. 10, an alternative embodiment of the textured portion 138 of the bag 20 is shown. The textured portion 138 includes a belt 42 and a yarn 140 that is positioned adjacent edge 34 of the upper end 24 of the bag 20. In the present embodiment, the yarn 140 is located on the outer portion of one of the yarns 16. warp from the warp layer 14 so that a portion of the yarn 140 is located between the warp yarn 16 and the tape 42.

[0068] The filament 140 is arranged in a non-linear wave pattern (e.g., square, triangular, sawtooth, sinusoidal, etc.). The wobble pattern 140 is generally an oscillating pattern. The oscillating pattern of the fibers 140 defines multiple peaks 148a and multiple valleys 148b. In the depicted embodiment, the oscillating pattern is generally sinusoidal.

[0069] Referring now to FIG. 11, an alternative embodiment of the textured portion 238 of the bag 20 is shown. The textured portion 238 has a plurality of filaments 240. The plurality of filaments includes a first filament 240a and a second filament 240b. The first fiber 240a is arranged in a first nonlinear wavelength pattern and the second fiber 240 is arranged in a second nonlinear wavy pattern. In the depicted embodiment, the first and second wave pattern are generally sinusoidal. The second wave pattern is remote from the first wave pattern. For example, in the depicted embodiment, the first and second waveform pattern are 180 ° out of phase.

[0070] 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 positioned between the bottom and top ends 22, 24 of the bag 20.

[0071] The label 50 has an outer surface 52 and an opposite inner surface. The outer surface 52 is adapted to bear markings (e.g., colors, numbers, letters, symbols, etc.) relating to information (e.g., manufacturer, weight, ingredients, dates, nutrition information, etc.) about the contents of the inner recess 28 of the bag. 20.

[0072] The interior surface of label 50 has an adhesive free surface. It is understood that the term "glue-free" means that the inner surface does not contain an applied glue or adhesive coating. The inner surface of the label 50 is attached to the composite fibers of the bag fabric 20 by the application of heat and pressure. In one embodiment, the inner surface of the label 50 is secured to the matrix plies

ΕΡ2486178Β1 bag 20. In another embodiment, the inner surface of the label 50 is attached to the warp and weft layers of the bag 20.

[0073] Referring now to FIG. 12, an alternative embodiment of a bag 320 that is constructed of netting material in accordance with the present disclosure is shown. The bag 320 includes a lower end 322 and an opposingly positioned upper end 324 and a side seam 326 that extends between the lower and upper ends 322, 324.

[0074] The lower end 322 is a closed end while the upper end 324 is open. The upper end 324 defines an opening 336 which provides access to the interior cavity 328 of the bag 320.

The bag 320 of this embodiment further includes a closure member 360. The closure member 360 is adapted to selectively close the opening 336 to prevent or block access to the inner recess 328 of the bag 320. In one embodiment, the closure member 360 is a warp-knitted fabric. . In another embodiment, the closure member 360 is a non-woven fabric. Closure member 360 can be manufactured from a thermoplastic material such as polyethylene, polypropylene, high density polyethylene, nylon, polyesters, etc.

[0076] The closure member 360 is located at the upper end 324 of the bag 320. The closure member 360 is positioned freely between the weft yarns 11, 12 so that the weft yarns 11, 12 can slide along the closure member 360. In the depicted embodiment, the closure member 360 is positioned freely between the weft fibers 11, 12 between the weft fibers 11, 12 so that the closure member 360 is generally parallel to the warp fibers 16 of the bag 320. While the closure member 360 is gripped between the weft fibers 11, 12, the closure member 360 is attached to the bag 320 at the side seam 320.

[0077] To close the top end opening 336 324, closure member 360 is pulled in a direction generally outwardly from top end 324. As closure member 360 is pulled, weft fibers 11, 12 slide along closure member 360 toward other weft fibers 11, 12 the fabrics of the bag 320 and form a bundle. As the weft fibers 11, 12 slide along the closure member 360, the size of the opening 336 is reduced. When the weft fibers 11, 12 form a bundle, closure member 360 may be clamped to secure the top end 324 in the closed position (i.e., when opening 336 is closed).

[0078] Referring now to FIG. 13, an alternative embodiment of a bag 520 that is constructed of the material of the present disclosure is shown. The bag 520 includes a lower end 522 and an opposing positioned end 524 and a side seam 526 that extends between the lower and upper ends 522, 524.

[0079] The lower end 522 is the closed end and the upper end 524 is the open end. Lower end 522 includes a seam 532 that is formed by sewing the first portion of the edge of the material together with the portion of the edge overlapping when the material is wrapped. The upper end 524 defines an opening 536 which provides access to the inner cavity 528 of the bag 520.

[0080] The bag 520 includes a plurality of bands 570. The plurality of bands 570 are adapted to increase the strength of the cylindrical bag 520 without significantly increasing the weight of the bag 520.

[0081] The plurality of strands 570 are placed in the bag 520 such that the strands 570 are generally parallel to the fibers of the warp 16. In one embodiment, strands 570 are located adjacent to the warp yarns 16. In another embodiment, strands 570 are located between adjacent warp fibers 16. In another embodiment, the strands 570 are positioned adjacent to the warp yarns.

The "2,486,178" 1 are located on the warp fibers 16. In one embodiment, each of the strands 570 has an end portion 572 that is secured at the side seam 526 of the bag 520.

[0082] The strips 570 have a tensile strength that is greater than or equal to the tensile strength of the warp fibers 16. The strips 570 may be manufactured from a variety of materials. In one embodiment, each of the bands 570 is a non-woven or thermoplastic material, such as a polyester material. In another embodiment, each of the strands 570 may be made of the thread used to secure the side seam 526 and the seam 532 at the lower end 522.

[0083] The bands 570 are spaced along the axial distance D of the bag 520. In one embodiment, the gaps between the bands 570 are fixed (i.e., the gaps between the bands 570 are equal). In another embodiment, the spacing between the bands 570 is variable so that the spacing between the bands is not equal.

[0084] In one embodiment, the axial distance D over which the bands 570 are located is equal to the length L (i.e., from the lower end 522 to the upper end 524) of the bag 520. In another embodiment, the bands 570 may be located along the length L depending on the particular particular. using the bag 530 such that the axial distance D is smaller than the length L of the bag 520. In one embodiment, bands 570 are located in the lower half of the bag 520 such that the axial distance D is less than or equal to 0.5L as measured from the lower end 522 of the bag 520. In one embodiment, bands 570 are located in the lower third of the bag 520 so that the axial distance D is less than or equal to 0.33L as measured from the lower end 522 of the bag 520. In one embodiment, bands 570 are located in the lower quarter of the bag 520 such that the axial distance D is less than or equal to 0.25L as measured from the lower end 522 of the bag 520.

[0085] Referring now to FIG. 14 and 15, an alternative embodiment of bands 570 for bag 520 is shown. In this alternative embodiment, bands 570 are located on the warp fiber 16 such that band 570 forms a wave pattern (e.g., square, triangular, toothed, sinusoidal, etc. ). In the depicted embodiment of FIG. 14, the wave pattern is generally sinusoidal in shape.

[0086] In the depicted embodiment of FIG. 15, a plurality of strands 570 are located on each fiber of the warp 16. The plurality of strands 570 include a first strand 570a and a second strand 570b. The first band 570a is located in the first wave pattern, and the second band 570b is located in the second wave pattern. In the depicted embodiment, the first and second waveform patterns are generally sinusoidal. The second wave pattern is shifted from the first wave pattern. For example, in the depicted embodiment, the first and second waveform patterns are 180 ° out of phase.

[0087] Being formed of ultra-mesh material, an L-seamed bag constructed in accordance with the present disclosure, referred to herein in brevity as a "new style" L-seam bag, exhibits excellent drape compared to prior art L-seamed bags. Traditionally, L-seam bags have been transported and stored in "bales" in which several thousand bags are pressed and tied together using twine and / or shrink film. Each bale typically comprises four or five stacks of the same number of stacked bags. The tied bales are then folded on a pallet and pressed to a final height, typically about 50 inches (127 cm), and the entire pallet is shrink wrapped. Then several pallets are placed on the truck for transport.

[0088] The drapeability of new style L-seam bags of ultra-mesh A material described above was tested against traditional Raschel knitted L-seam bags using this

ΕΡ2486178Β1 baling and palletizing process. Two sizes of each style of bag were tested: a 10 lb bag and a 5 lb bag. It should be noted at this point that bag sizes are often determined in the packaging industry as a function of their intended volumetric or weight capacity. Hence, a 10 lb bag is a bag that is designed to have a working capacity of 10 lb (4.5 kg) and a 5 lb. bag is a bag that is designed to have a working capacity of 5 lb (2.7 kg) , etc.

[0089] The bags were baled 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.

TABLE 4: STRAIGHTNESS OF SEAMED BAGS I

<td></td><td>10 lb. raschel</td><td>Ultra-Mesh 10 lbs</td><td>5 lb. raschel</td><td>Ultra-Mesh £ 5</td>

<td>Bag size</td><td>10 pounds</td><td>10 pounds</td><td>5 pounds</td><td>5 pounds</td>

<td>Number of bags / stack</td><td> 750</td><td> 1000</td><td> 600</td><td> 1000</td>

<td>Number of bags / bale</td><td> 3000</td><td> 4000</td><td> 3000</td><td> 5000</td>

<td>Bale size (cm)</td><td>52.1x116.8x35.6</td><td>52.1x116.8x22.9</td><td>58.4x114.3x33.7</td><td>53.3x116.8x25.4</td>

<td>Bale height (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>Number of Rows / Pile</td><td> 4</td><td> 6</td><td> 5</td><td> 6</td>

<td>Number of bales / pallet</td><td> 8</td><td> 12</td><td> 10</td><td> 12</td>

<td>Number of bags / pallet</td><td> 24000</td><td> 48000</td><td> 30000</td><td> 60000</td>

[0090] The improvement is significant.

[0091] As can be seen from Table 4 above, 10 lb. L-seamed raschel bags were pressed to a height of 14 inches (35.6 cm) by baling to obtain a 43.7 bags / cm stack when the stacked bags were subjected to force of 267 kN. Hence, each bale contained 3000 bags. As a comparison, 4,000 10-pound L-seamed ultra-mesh bags were pressed to a height of 9 inches (22.3 cm) by the baling process to give a stack of 21.1 bags / cm when the stacked bags were subjected to a force of 267 kN. . These tests therefore confirm that subjecting stacks of L-seam bags constructed according to the present disclosure to a force of 267 kN creates a stack of more than 25 bags / cm, more than 30 bags / cm, and even more than 35 bags / cm.

[0092] Due to the reduced bale height of the new style mesh bags compared to Raschel knitted L-seam bags, it was possible to store more bales on a pallet. For transportation and storage purposes, the maximum possible height of a pallet and the articles stored thereon is typically considered to be about 50 inches (127 cm). L-seamed 10lb Raschel bag bales are typically stacked on a pallet in four layers, each containing two bales. Due to the reduced height of the new style 10lb L-seam bags made of ultra-mesh A material, two additional rows of bales can be stored on the pallet to substantially the same height. The same palette can

ΕΡ2486178Β1 therefore accommodate 12 bales of L-seam 10 lb. bags of the new style compared with 8 bales of traditional L-seamed 10 lb. raschel bags. As a result, 48,000 new style 10 pound L-seam bags can be stored on the pallet compared to 24,000 L-seamed 10 pound raschel bags in the prior art. 50 percent more bags can be transported and stored in a given volume. The space requirements for transportation and storage are dramatically reduced, further reducing the carbon footprint of the bags. Table 4 confirms that a similar improvement was achieved with the 5 lb. L-seam ultra mesh bags.

3. Shape, fill and seal bags

[0093] Ultra-mesh materials as described herein, or other materials having at least some of the characteristics of ultra-mesh materials, can also be used to make multi-substrate bags having both sheet and mesh portions with at least one thermally bonded seam. While form-fill-and-seal (FFS) bags taking the form of four-panel vertical form-fill-seal (VFFS) bags will now be described, at least many of the concepts discussed here also apply to other vertical form-fill and seal bags. , horizontal form, fill and seal (HFFS) bags and many other multi-substrate FFS bags having an at least thermally bonded end seam sealing the mesh and sheet portions of the bag together.

[0094] Turning first to FIG. 16-21 and in particular to FIG. 16-18, the first embodiment of an FFS 1020 bag includes a so-called four-panel VFFS bag having a front 1020, back 1024, left 1026 and right 1028 sides, and top 1030 and bottom 1032 ends. The bag is filled with products. fruit and vegetable or other food products. The term "full" as used herein does not mean that the entire internal volume of the bag has to be occupied by merchandise. Indeed, in commercial applications, a bag is typically "filled" to its nominal weight of stored goods when goods occupy less than 70%, often less than 50%, of the inside volume of the bag. The goods that can be stored in these bags can be, for example, nuts, oranges, potatoes, onions, seafood (such as shrimp, mussels, or mussels), newspapers, dried beans, or wrapped candies.

The bag 1020 is generally square along most of its length when filled with materials, except that it is kinked at the top and bottom ends 1030 and 1032 where opposite front and rear sides are welded together with the left and right ends pressed between them. 1026 and 1028. It may also be rectangular or some other polygonal shape in cross section and exhibit many, if not all, of the features discussed herein. Left and right sides 1026 and 1028 are formed of an inserted mesh material 1100. At least one end of each of the outer portions of the front and back sides 1022 and 1024 is formed at least in part of sheet material 1102 extending along the bag from the sealed end of the bag. Both ends of one or both of the front and back sides may be made of the same material. In the embodiment illustrated, the sheet material extends the entire length of the front and back sides. In the bag 1020 of the illustrated embodiment, the back side 1024 is formed entirely of sheet material 1102 and the front side 1022 of the bag 1020 is formed of a mesh material covered with sheet material 1102.

[0096] Referring now to FIG. 20 and 21, sheet material 1102 of the front side 1022 of the bag 1020 preferably extends across the entire width of the front side 1022, but may extend less than the full width as needed. It is heat sealed to the underlying mesh fabric 1100 at its edges through seams 1034, 1036 which are approximately% inch (0.64 cm) to% inch (0.95 cm) wide. The back of 1024 bags 1020 has two vertically extending seams 1038, 1040 at its corners, where the foil material 1102 is applied over the edges of the fabric

ΕΡ2486178Β1 mesh 1100. Both seams 1038, 1040 include overlapping seams. At least lower end 1032 is closed, possibly by sewing or stapling, but preferably by thermal bonding. In the illustrated embodiment, both the top and bottom ends 1030 and 1032 of the bag 1020 are closed by thermally bonded seams. These seams may take the form of lap or detachable seams 1042, 1044 formed by pressing two welding bars together, also discussed below. Alternatively, they may be formed by other seams such as overlapping seams. The top and bottom seams 1042, 1044 typically have a length L of about% inch (0.95 cm) to% inch (1.27 cm). The illustrated bag 1020 has a storage capacity of one to three pounds and is approximately 4 inches (10.2 cm) wide by 10 inches (25.4 cm) high. However, the concepts discussed here are equally applicable to larger or smaller bags of different proportions.

[0097] The sheet material 1102 may be any sheet material that can be heat-sealed to itself or to other materials. Preferably it is capable of receiving markings on its outer layer. A material made entirely or in part of a synthetic resin film material may be sufficient. One such material is a so-called PET laminate having a thin layer of relatively high melting point polyester material serving as a printing layer laminated onto a relatively thin layer of linear low density polyethylene (LLDPE) material having a relatively low melting point. The LLDPE material melts during the heat bonding process, welding the foil material to adjacent materials. Material about 3 mils (0.076 cm) thick is preferred. However, as discussed in more detail below, other materials of various thicknesses have been successfully tested. Other sheet materials can also be used.

[0098] The mesh material 1100 is ultra-mesh, and is thus formed of a plurality of intersecting fibers, at least a portion of which are composite fibers formed of a composite material having a high melting "support" portion and a relatively high-melting "bonding" portion. low melting point. It may be in the form of one of the nonwovens generally described with reference to FIG. 1-7.

[0099] Turning now to FIG. 22 and 23, bags 1020 can be produced on a vertical form, fill and seal machine 1050 that forms product-filled web bags 1060 and 1062 of mesh material 1100 and sheet material 1102, respectively. Machine 1050 includes a frame 1052, a substrate forming station 1054, product dispenser 1056 and assembly 1058 form, fill, and seal. A substrate forming station 1054 forms a continuous strip of composite substrate 1200 from rolls 1060, 1062 of mesh material and film. The form, fill, and seal assembly 1058 receives batches of product from the product dispenser 1056 and simultaneously forms bags 1020 from the substrate 1200, fills the bags 1020 with product, and seals the ends of the formed and filled bags 1020.

[0100] The substrate forming station 1054 includes first and second picking rolls 1060 and 1062 for mesh material 1100 and film 1102, respectively. The mesh material 1100 is preferably wound onto a roll in a continuous web 1202 with warp yarns extending along the belt or in the machine direction. The warp fibers may eventually extend vertically into the finished bags. The second pickup roll 1062 supports a roll of laminated PET film material printed with two adjacent repeating patterns of printed indicia positioned one after the other in line with each other. Downstream of the pickup roll 1062 is a cutter 1064 operable to cut the film 1102 into two labeled strips or print bands 1066, 1068. An arrangement of guide rollers and guide bar guides guides the printing tapes 1066, 1068 and the continuous web 1202 of mesh material 1100 to the substrate forming unit 1070, where the edge of the first printing ribbon 1068 is thermally bonded to the edge of the mesh belt 120 and the second printing ribbon 1066 is

The "2486178" 1 is thermally bonded to the outer surface of the webbing 1202 spaced from the first print web 1068. The segments of these print tapes eventually form the back and front of the finished bags, respectively. Thermally bonding is preferably performed by an array of heated spars 1072 and platen 1074 in a manner generally known in the art. A suitable system for slitting the foil bearing the markings into two printing ribbons and for heat bonding the printing ribbons to the substrate is known, for example, from the international publication WO 99/58323 to Winiecke.

[0101] The resulting substrate 1200 is illustrated in FIG. 24. It comprises a continuous web of netting 1202 having one band of print 1066 applied to the outer surface approximately in the center between the first and second edges 1204, 1206 of the web 1202. The web of print 1066 is thermally bonded to web 1202 on overlapping seams 1208 and 1210 extending to the outer surface. parallel to the edge of the 1066 strip. The first edge 1212 of the second belt 1068 is thermally bonded to the second edge 1206 of the web belt 1202 through an overlay seam 1214. When the substrate 1200 is then formed into a bag, the first printing strip segment 1066 forms the outer surface of the front side of the bag, the second printing strip segment 1068 forms the back side of the bag, the web segment 1216 between the first and second printing strips 1066 and 1068 forms the right side wall of the bag, and a segment of the web portion 1218 to the left of the first printed band 1066 forms the left side wall of the bag.

[0102] It should be noted that the substrate 1200 need not be formed on a vertical form, fill and seal machine 1050. Instead, it can be formed with separate converting equipment located either in the same location as the vertical form, fill and seal machine 1050, or at a different location. The optional formation of the substrate at a remote location would offer the bag maker the option that it would not be necessary to purchase and handle multiple roles of different types of materials. It would also reduce the capital burden of acquiring and operating a vertical form, fill and seal machine as the machine would not require a substrate forming station.

[0103] Referring again to FIG. 22, the function of product dispenser 1056 is to dispense batches of product weighed by a computer weighing device (not shown) at the correct time in the machine cycle 1050. Suitable computer weighing devices that can perform this function are shown in US Patent Nos. 4,538,693 and 4,901,807, which are here incorporated by reference.

[0104] Referring to FIG. 22 and 23, the form-fill-seal assembly 1050 includes a square vertical forming tube 1080 mounted on the frame 1052 immediately below the product dispenser 1056 so that the product dispensed from dispenser 1056 is received inside the vertical forming tube 1080. The forming arm 1082 is attached to the frame 1052 adjacent to but spaced from the top end of the vertical forming tube 1080. Instead of a square forming tube, other polygonal forming tubes or even round or oval tubes can be used. The forming arm 1082 directs the substrate 1200 around the forming tube 1080 to form a generally square tubular structure with the outer edge of the print strip 1068 overlapping the outer surface of the opposite edge of the web of web 1202. Vertical seal bar 1084 is supported adjacent the top end of the vertical forming tube 1080. . The vertical forming bar 1084 thermally bonds the overlapping edge of the print strip 1068 to the outer edge of the webbing web 1202 at the corner of the front of the finished bag, creating a vertical overlay seam, thereby forming a generally tubular sleeve 1087. On opposite sides of the vertical forming tube 1080 below the seal bar 1084 a pair of conveyor belts 1086, 1088 are provided. The conveyor belts 1086, 1088 are selectively controlled to index the sleeve 1087 down along the tube 1080 to the length of one bag 1020 to move the corresponding amount

Do2486178Β1 of substrate 1200 and to contact the forming arm 1082 and allow the second bag 1020 to be formed.

[0105] The end seal and slitting device 1090 is positioned beneath the tube 1080. The device 1090 includes a pair of opposing heated seal bars 1092, 1094 that can selectively move toward each other, horizontally compressing the sleeve 1087 above the product level in the filled bag to form an end seal. a seam that forms a side top seam 1042 in a bag 1020 containing a product and a side bottom seam 1044 in a further bag 1020 to be filled with a product. The seam is formed by heating bonding layers of different materials so as to bond the first and second webs 1066, 1068 to each other and to the overlapping layers of the webbing 1202, as generally seen in FIG. 23. Device 1090 also includes a blade (not shown) that cuts the filled and sealed bag 1020 from the rest of substrate sleeve 1087 such that the filled and sealed bag 1020 falls down into conveyor 1051 which takes the filled and sealed bag 1020 from machine 1050.

[0106] Below the exit hole in pipe 1080 immediately downstream of the welding and cutting device 1090 are left and right wedge bars 1096, 1098. The bars are driven by actuators such as air cylinders 1097 and 1099 so as to bend the left and right side centers 1026 and 1028 of the bag 1020 between the edges of the front and back sides 1022 and 1024 just before closing the seal bars 1092, 1094, thereby forming folds in the sides of the bag 1020. The bars 1096, 1098 are held in this position during the heating and welding operation and are pulled back simultaneously with the welding bars of the welding and cutting device 109 0. The depth of the folds depends on the pitch of the wedging blades 1096, 1098. In the illustrated embodiment, the folds extend inward or almost towards the center. inside the bag 1020 as can be seen in the bottom view of FIG. 20.

[0107] The relatively light, open nature of the mesh material forming the mesh material 1100 of the finished bag 1020, combined with its fiber composition, allows the vertical form, fill, weld 1050 machine to produce excellent quality top and side seams at a much faster speed than would be possible. for previously known multi-substrate materials having other mesh materials. The nature of this seam can be judged with reference to Fig. 19. Low density material from different layers melts during the heat sealing process and flows between and around the high density fibers. This causes the low density material to at least partially surround the fiber support portions of the mesh material layers. Importantly, it also allows the film to be significantly bonded to the film of the outer layers of films 1022 and 1025 through openings in the mesh layers 1026 and 1028. Ultra-mesh 1100 also has relatively low kinetic coefficients of friction compared to other mesh materials, which increases the ability of the 1050 machine to pull substrates containing this mesh material at a higher speed without slippage. Tests have shown that multi-substrate VFFS bags with seam strength much better than the prior art bags can be produced at a speed of 25 bags per minute or even 50 bags per minute or greater. Comparable multi-substrate VFFS bags using MS CLAF® as the mesh material of their substrates can be produced at a speed of no more than about 15-22 bags per minute. The tests to support these conclusions are discussed in detail below.

[0108] Referring again to FIG. 16-18 and 27, the thus formed, filled and welded bag 1020 is aesthetically pleasing as the foil strip of the front side 1022 lies very evenly on the relatively thin and light underneath mesh of the layer 1100 formed of ultra-mesh material. In addition, the underside mesh material 1100 has greater dimensional stability than traditional knitted and extruded mesh fabrics. Unlike the previously known knitted and extruded mesh fabrics used in bags, the stability of the mesh material 1100 combined with the geometry of the bag, where the side folds of the polygonal bag extend almost to the longitudinal line

ΕΡ2486178Β1 of the middle bag, forces the goods in the bag to take the shape of the bag. The bag 1020 thus maintains its square, rectangular, or other polygonal shape after it is filled with goods. The desired degree of folding may vary depending on, for example, the size of the bag. Generally, shallower creasing is required to achieve dimensional stability in larger bags. The bag 1020 may even stand upright and generally maintains its shape.

[0109] The excellent dimensional stability of form-fill and seal bags constructed as discussed herein allows the bags disclosed herein to maintain their desired height and cross-section extremely well even when filled with products. A bag 1020 constructed as discussed herein with reference to FIG. 16-21 using ultra-mesh material A as the mesh material is shown after being formed, filled, and placed on a flat surface such as a table. Tests have shown that when a bag is filled to its nominal weight with goods and placed on a flat surface, it maintains a high percentage of its original height. The initial height Hi, as defined herein, is the vertical distance between the bottom surface of the bag to the location that will form the top inner surface after the bag is sealed, measured just prior to filling the bag with goods during the molding and filling process. This height can be measured or at least estimated to a reasonable level of precision during the molding and filling process by measuring the distance from the bottom of the bag to the top end of the fill tube (see FIG. 22 and 23) before putting the goods into the bag. The final height Hf as defined herein is the vertical distance from the bottom surface of the bag to the top of the goods in the bag, after the bag has been formed, filled with goods and placed on the surface without top or side support. This final height can also be considered as the final effective height of the bag as the interior space of the bag above the product is effectively wasted. Tests have shown that the final height Hf of the 1020 bag is at least 35% of the original height. In fact, the final height Hf was found to be more than 50% and even more than 60% of the initial height Hi of the bag.

[0110] The beneficial effects of this excellent dimensional stability can be assessed with reference to FIG. 27, in which the bag 1020 is shown next to the form, fill, seal bags 1021 and 1023 of the prior art. The bag 1021 is made of tubular knitted synthetic mesh fabric available from GIRO GH SA of Badalona, ​​Spain, under the trade name GIRO®. Bag 1023 is made of extruded mesh material commercially available from Conwed Global Netting Solutions, Minneapolis, MN under the trademark VEXAR®. FIG. 27 shows that the heights Hf and Hf of the bags 1021 and 1023 are much smaller than the end height Hf of the bag made according to the present disclosure. The bags 1021 and 1023 have a high "slippage" effect, while there is substantially no slippage of the bag constructed in accordance with the present disclosure.

[0111] The height maintenance characteristics visually visualized in FIG 27 were computed numerically and recorded for a new bag sample. The bags made of GIRO® and VEXAR® materials were 2 lb. bags containing oranges and clementines. The new bag was a 3 pound bag constructed as discussed in conjunction with FIG. 16-21, and having ultra-mesh A material as the mesh material. The start and end heights Hi and Hf were measured and recorded for each bag, and the percentage of height retention (Hf / Hi) X 100 was calculated and recorded. Differences in rated capacity and type of goods stored between the new style bag and the prior art bags were found to be non-influencing. significant for the percentage of keeping altitude. The results are tabulated in Table 5 below, where the different bags were identified by the mesh material contained in the bag.

ΕΡ2486178Β1

TABLE 5: KEEPING THE HEIGHT OF THE FFS BAG

<td>Mesh material type</td><td>Initial bag height (cm)</td><td>Final bag height (cm)</td><td>Maintaining altitude (%)</td>

<td>GIRO® knitted sleeve</td><td> 36,8</td><td> 8,9</td><td> 24</td>

<td>Extruded VEXAR® mesh</td><td> 35,7</td><td> 8,9</td><td> 24</td>

<td>Ultra-Mesh A</td><td> 34,9</td><td> 22,9</td><td> 66</td>

[0112] The measurements recorded in Table 5 confirm that the multi-substrate bags constructed with the ultra-mesh material exhibit significantly improved height retention than the prior art knitted sleeve and extruded mesh mesh bags.

[0113] The dimensional stability of the bag 1020 is also reflected by its circumferential stability. The term "circumferential stability" as used herein refers to the ability of the bag to maintain a constant cross-sectional shape and circumference along at least a significant portion of the bag's length after it has been filled and placed on a surface unsupported, i.e. without top or side support. This is another measure of "sinking." Each VFFS bag will have an initial diameter Di and a resulting initial circumference that substantially matches the circumference of the tube from which it is made, and this initial diameter Di will be relatively uniform along at least most of the length of the bag. A bag with high circumferential stability will exhibit little slippage and thus will have an end maximum diameter Df relatively close to the original maximum bag diameter which is assumed to be the same as the forming tube diameter of a VFFS machine. This is the case with a bag 1020 constructed using ultra-mesh A material, where the Df / D X 100 is at least 70% and even 90% or even more. In contrast, the Df / Di X 100 for prior art bags made of prior art GIRO® tubular knitted fabric and VEXAR® extruded mesh materials are typically less than 50%.

[0114] The ultra-mesh material also offers excellent ventilation for the products stored in the bag. The excellent seam strength of the 1020 bag allows the manufacture of larger and / or more capacious bags. The ability to seam quickly and pull substrate through the machine allows bags to be formed and filled at higher speeds.

[0115] An alternative configuration of the bag 1220 is shown in Fig. 25. The bag 1220 is identical to the bag 1020 of FIG. 161-21 in all respects except that the front side 1222 is solely formed from the strip of thermoplastic film 1202 as opposed to the strip of thermoplastic film underneath the mesh material. Notice the cut-out portion 1223 in Fig. 25. The substrate 1300 for making this bag, shown in FIG. 26, consists of spaced apart strips 1316 and 1318 of ultra-mesh material that are joined together by two printed strips 1266, 1268. Printed strip 1266 fills the gap between two spaced strips 1316 and 1318. Referring again to FIG. 25, back side 1224, and inserted left and right sides 1226 and 1228 are identical to the corresponding pages 1024, 1026 and 1028 of the bag 1020 in the first embodiment. The seals at opposite ends of the top and bottom seams 1242, 1244 are also identical to the seams of the first embodiment bag along at least most of their lengths.

ΕΡ2486178Β1

[0116] The bag 1220 of FIG. 25 also has horizontally spaced finger openings 1250 1252 formed by the bag front to back between two spaced seams 1242, 1242 'near the top of the bag, allowing the bag to be supported at least in part by the insertion of fingers through the openings. The holes 1250, 1252 can be punctured through the bag by punches mounted or otherwise operating in conjunction with the sealing and cutting device 1090 of the form, fill, seal machine 1050, or some other equipment. In order not to deal with pieces that would be produced by removing all material from the punctured holes, the holes are preferably punched so as to leave the flaps. The bag 1020 of FIG. 16-21 can also be formed with finger openings if desired.

EXAMPLES

[0117] The superiority of the seam strength obtained by using the substrate described above was confirmed by several series of tests designed to replicate the end seams formed from lap seams on the bag. Unless otherwise indicated, the test material consisted of a 1 inch (2.54 cm) wide strip of layered fabric consisting of first and second opposing outer layers of the above-described PET film material and four layers between layers of "ultra-mesh material" representing the fold area. at the ends of a four-panel pleated bag. The composition of the ultra-mesh material varied depending on the test. These strips of material were then clamped between two heated bars, designed to simulate the seal bars of a vertical form, fill and weld type machine, at a clamp pressure of 700-710 kPa for specified periods or "residence times". Residence times varied depending on the test. The seam was then separated by pulling the bonded materials up and down until the seam is released and the maximum force applied and the time required to achieve that force from the start of applying force. These series of tests will now be described and conclusions drawn.

Test Series 1 - Co-extruded HDPE mesh, 10 mm

[0118] In this series of tests, a substrate having ultra-mesh knitted fabric of the type generally illustrated above in FIG. 4-7. The knitted fabric had a grammage of 20 g / m² and consisted of two layers of co-extruded fiber warp flanking the two layers of high-density polyethylene (HDPE) weft. The weft fibers extended parallel to the machine direction. The weft fibers extended at angles of about 40 ° from the cross machine direction. Thus, each filament extended at an angle of about 20 ° to the cross machine direction. Each weft fiber was formed of an 80 micron thick three layer web having a 50 micron thick HDPE layer sandwiched between two 15 micron thick LLDPE linear low density polyethylene layers. The web was stretched 6: 1 to form fibers that were incorporated into the knitted fabric, whereupon the composite fiber was about 0.03 mm thick and about 1.5 mm wide. The warp fibers of each ply were spaced 10 mm apart. The fabric was an alternating fabric in which the warp yarns of the underlayer were about halfway spaced between the warp yarns of the upper layer, resulting in a warp fiber spacing of about 5 mm in the fabric. Each fiber of the weft layer was about 0.04 mm thick and about 1.5 mm wide. Three samples were tested under the conditions listed in Table 6 below:

TABLE 6: co-extruded HDPE mesh, 10MM, seam characteristics

ΕΡ2486178Β1

<td>A sample</td><td>Temp. (° C)</td><td>Residence time (SeK.)</td><td>Maximum force (N)</td><td>Time to maximum force (sec.)</td>

<td> 1</td><td> 149</td><td> 0,75</td><td> 6,6</td><td> 0,68</td>

<td> 2</td><td> 149</td><td> 0,75</td><td> 6,2</td><td> 0,46</td>

<td> 3</td><td> 149</td><td> 0,25</td><td> 8,0</td><td> 0,62</td>

[0119] This series of tests showed that forming the bags under the operating conditions of heat and residence time required to form acceptable seals in a substrate having ultra-mesh material as part of the mesh produced a very strong seal. The time required to reach maximum strength, serving as a measure of how quickly a seam formed, was more than acceptable. Surprisingly, in Test # 3, it was found that reducing the residence time to as little as 0.25 seconds actually produced a stronger seal with 8.0N breaking strength.

Test series 2 - co-extrudate / co-extrudate stack, 8 mm

[0120] The mesh material of the substrate of Test Series 2 was similar in structure to the material shown in FIG. 1-3. It consisted of two evenly or "stacked" warp yarns surrounding the intersecting weft yarns. Both the warp and weft fibers were coextruded trilayer fibers of the type described above in connection with Test Run 1. The warp fiber spacing was 8 mm. The test results are summarized in Table 7 below:

TABLE 7: KO-EXTRUDATE PACK, 8 MM, SEAM CHARACTERISTICS

<td>A sample</td><td>Temp (° C)</td><td>Residence time (sec.)</td><td>Maximum force (N)</td><td>Time to maximum force (sec.)</td>

<td> 1</td><td> 149</td><td> 0,25</td><td> 5,5</td><td> 0,48</td>

<td> 2</td><td> 149</td><td> 0,17</td><td> 4,5</td><td> 0,22</td>

<td> 3</td><td> 149</td><td> 0,10</td><td> 3,7</td><td> 0,35</td>

<td> 4</td><td> 143</td><td> 0,10</td><td> 5,5</td><td> 0,39</td>

<td> 5</td><td> 138</td><td> 0,10</td><td> 6,6</td><td> 0,45</td>

<td> 6</td><td> 138</td><td> 0,10</td><td> 6,6</td><td> 0,38</td>

[0121] These tests revealed that excellent lap seam strengths were obtained, commensurate with those observed in Test Series 1 at even lower residence times and temperatures. The ability to produce seams of these high strengths with

ΕΡ2486178Β1 residence times of 0.10 seconds slowly for easy production of vertical form, fill and seal bags on the machine described above at speeds above 50 bags per minute.

These tests revealed that the excellent fin seam strengths commensurate with those observed in Test Series 1 were obtained at even smaller dwell times and reduced temperatures. Being able to produce seams of these high strengths with dwell times on the order of only 0.10 second would easily permit the production of vertical form, fili and seal bags on the machine described above at rates in excess of 50 bags per minute.

Test Series 3 - Co-extruded HDPE mesh, 10mm

[0122] In Test Series 3, the same ultra-mesh material was tested as in Test Series 1 at reduced temperatures and reduced residence times. The results are summarized in Table 8:

TABLE 8: Seam characteristics for 10MM HDPE co-extruded mesh

<td>A sample</td><td>Temp. (° C)</td><td>Residence time (sec.)</td><td>Maximum force (N)</td><td>Time to maximum force (sec.)</td>

<td> 1</td><td> 149</td><td> 0,10</td><td> 6,6</td><td> 0,28</td>

<td> 2</td><td> 132</td><td> 0,10</td><td> 6,6</td><td> 0,42</td>

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

<td> 4</td><td> 127</td><td> 0,10</td><td> 1,8</td><td> 0,27</td>

[0123] It was surprisingly observed that very strong lap welds were obtained having breaking forces above 6.0 N with a residence time of only 0.10 seconds and low temperatures of 132 ° C. Significant reduction in seam strength was noted only at temperatures below 130 ° C.

Unexpectedly, it was observed that very strong fin seals having failure forces in excess of 6.0 N were found at a dwell time of only 0.10 second at temperatures as Iow as 132 ° C. A significant reduction in seam strength was noted only at temperatures below 130 ° C.

Test Series 4 - pre-labeled co-extruded HDPE mesh, 10

[0124] The substrate tested in this series of tests was identical to the ultra-mesh material tested above in test series 1 and 3, except that the substrate was previously labeled with a 3.0 mil (0.076 mm) PET laminate. That is, the film material strips were attached to the ultra-mesh material using separate processing equipment rather than the processing equipment used in the form, fill and weld machine described above. Testing results are summarized in Table 9 below:

ΕΡ2486178Β1

TABLE 9: Seam characteristics for pre-labeled co-extruded 10MM HDPE mesh material

<td>A sample</td><td>Temp (° C)</td><td>Residence time (sec.)</td><td>Maximum force (N)</td><td>Time to maximum force (sec.)</td>

<td> 1</td><td> 149</td><td> 0,10</td><td> 5,6</td><td> 0,32</td>

<td> 2</td><td> 149</td><td> 0,10</td><td> 11,0</td><td> 0,57</td>

<td> 3</td><td> 149</td><td> 0,10</td><td> 6,0</td><td> 0,35</td>

<td> 4</td><td> 149</td><td> 0,10</td><td> 5,4</td><td> 0,.45</td>

[0125] These tests confirmed that, for pre-labeled substrates, seam strengths comparable to those discussed above can be achieved at bag production speeds commensurate with those discussed above in connection with test series 1 and 3.

4. Multisubstrate bags

[0126] As noted above, the netting materials described herein can be used to make the mesh portions of multi-substrate bags having a foil portion and a mesh portion. "Multisubstrate bags" are bags having first and second side walls wherein at least a significant portion of one side wall is made of mesh material and at least a substantial portion of the other side wall is made of sheet material. The first and second side walls may be welded directly to each other or may be joined by additional side walls extending through the gap between the first and second side walls.

[0127] Turning now to FIG. 28-35, and initially in particular to FIG. 28-30, a bag 2020 constructed partially of mesh material is a bag having front and back sides 2022 and 2024, left and right edges 2026 and 2028, and top and bottom ends 2030 and 2032. The mating sides of side edges 2026 and 2028 are formed of bonded sides. imposition seams, but may be formed of a lap seam or other. At least a significant portion of the first sidewall 2022 of the bag 2020 is formed of a web 2034 of mesh material. The upper edge 2036 of the first sidewall 2022 may be provided with a reinforcement strip 2036 to reinforce the upper edges of the side seams 2026, 2028, thereby preventing the seams 2026, 2028 from separating during bag filling and subsequent handling operations.

[0128] Referring now to FIG. 28-30, the second side wall 2024 of the illustrated embodiment is made entirely of sheet material. Alternatively, a mesh strip may be positioned in the second bag side wall between the top and bottom ends 2020 and 2032. As yet another alternative, the entire bottom portion of the second side wall 2024 may be formed of the same or different mesh material as the first side wall 2022 and the top portion may be formed of sheet material. In this case, the first and second side walls may be at least generally of the same structure. Regardless of the structure of the second side wall 2024, vents or breathing holes 2025 may be formed in the sheet material as desired.

ΕΡ2486178Β1

[0129] One or more ultra-mesh materials of the type described in Chapter 1 above are well suited for the netting, including but not limited to one or more of the materials illustrated in FIG. 1-7.

[0130] The strip of film forming the second side wall 2024 is formed of a sheet material such as a film material. One such film material is formed at least in part from synthetic film material such as polyethylene or polypropylene, many types of which are commercially available. An example is a co-extruded three-layer film having an outer layer of LLDPE, a middle layer of LLDPE blend, and an inner layer of quality LLDPE. The film can be easily converted into bags using existing bag making equipment and can be easily handled by existing bag filling machines. It is also FDA compliant for direct food contact. It can also be dyed or tinted as needed and can be printed on its outer surface. Another example is 2.25 mil (0.057 mm) LDPE film with EVA added.

[0131] The thickness of the film depends on the type of film and the intended use, including the size of the bag in which the film is intended to be used. For a three-layer co-extruded film of the type described above, the film will typically be about 1.35 mil (0.34 mm) to 1.5 mil (0.38 mm) thick for a 5-pound bag and about 1.65 mil (0.042 mm) thick. ) to approximately 1.74 mils (0.44 mm) for a 10 pound bag.

[0132] The specific horizontal and vertical dimensions of the side walls 2022, 2024 and their thickness are typically determined based on the expected weight and size of the fruit and vegetable products to be bagged by an automatic fruit and vegetable packing machine. It should be noted that "sizes" of bags are generally defined in the art in terms of their storage capacity in pounds. Thus, a "5-pound bag" of a given style is sized to accommodate 5 pounds (2.27 kg) of a specific article or type of article. The following card gives examples of dimensions for various sizes of bags.

<td colspan="2">WEIGHT OF FRUIT AND VEGETABLE PRODUCTS</td><td>BAG WALL SIZE</td>

<td>2 pounds</td><td>(0.91 kg)</td><td>10 inches (25.4 cm) by 16 inches in (40.6 cm)</td>

<td>3 pounds</td><td>(1.4 kg)</td><td>10 inches (25.4 cm) by 16 inches (40.6 cm)</td>

<td>4 pounds</td><td>(1.8 kg)</td><td>10 inches (25.4 cm) by 18 inches (45.7 cm)</td>

<td>5 pounds</td><td>(2.3 kg)</td><td>10 inches (25.4 cm) by 18 inches (45.7 cm)</td>

<td>10 pounds</td><td>(4.5 kg)</td><td>11.5 inches (26.7 cm) by 23 inches (58.4 cm)</td>

[0133] The vertical side seams 2026, 2028 can be of any desired width depending on the retention strength desired for the bag 2020 along its vertical side seams. Widths in the range of% inch (0.95 cm) to% inch (1.59 cm) are typical. The joining of the side walls 2022 and 2024 at the seams 2024 can be performed by any bonding or welding technique such as heat, glue, sealant or the like using any of the existing bag making machines. Thermal bonding is preferred.

ΕΡ2486178Β1

[0134] Referring to FIG. 31 and 35, the bottom of foil sidewall 2024 extends beyond the bottom of mesh sidewall 2022 to form a flap 2046 that folds over the outer surface of mesh sidewall 2022 with a small gap 2048 formed between the bottom edge of mesh web 2034 and the bottom 2032 of bag 2020. 2046 is thermally bonded to web 2034 to form a lower, horizontally extending lap seam 2050. As a result, the bottom 2032 of the interior of the bag 2020 is formed from a fold in the foil side wall 2024 and not from a seam. The length of the tab 2046 and the degree to which it overlaps the web 2034 depends on the intended use and manufacturer's preference. In the illustrated embodiment, the length of the flap 2046 from the bottom edge 2032 of the bag 2022 to the top of the flap 2046 is approximately 3.5 inches (8.9 cm). It overlaps a strip of mesh approximately 1.25 inches (3.2 cm).

[0135] Alternatively, the mesh strip 2234 may extend almost to the bottom of the bag 2220 as seen at 31B, or it may extend even further to the front side of the bag 2220 than is illustrated in FIG. 31. The bag 2220 of the embodiment of FIG. 31B is otherwise identical to the bag of FIG. 28-31 and 32-35. Elements of this embodiment are thus identified by the same reference numerals as the elements of the embodiment of FIG. 28-31 and 32-35, with increments of 100. The same incremental technique is used throughout the description to denote corresponding parts of different embodiments.

[0136] Providing at least the bottom of the bag as a wrapped synthetic resin film pocket greatly strengthens the 2020 bag and greatly reduces the chances of breaking during bag filling and onward handling operations as articles falling into the bag hit the relatively tight fold as opposed to relatively weak curl. seam. However, this particular configuration at the bottom is not critical. For example, more conventional flatlock seams of the type disclosed in, e.g., US Patent No. 3,554,368 or welded seams, of the type disclosed in, e.g., US Patent No. 3,123,279, may also be used.

[0137] Grip openings 2040 may be formed in the extension of one of the side walls to allow the bag 2020 to be hung from the gripper pins of commercially available automatic bag filling equipment with fresh vegetables and fruit, available e.g. from Ag-Pak, Inc. of Gasport, NY or Volm Companies of Antigo, Wl. The gripping holes 2040 should be arranged to mate with the gripper pins to allow the bag 2020 to be hung in the automatic fresh fruit and vegetable packing machine while it is being filled with fresh vegetables or fruit or other product. The size, location, and number of nip holes 2040 is dependent upon the type of particular bag filling machine with which the bags are to be used. A typical catch hole is about% of an inch (1.6 cm) in diameter. The side of the bag opposite to the side having the gripping openings is usually considered to be the front of the bag, since this side faces outward when the bag is filled. In the illustrated embodiment where the mesh sidewall 2022 forms the front of the bag 2020, gripping openings 2040 are formed in a portion 2039 of the foil sidewall 2024 that extends above the top of the reinforcement strip 2036 (see FIGS. 28, 29, and 35). Portion 2039 may also be formed of either a separate strip or integral with the rest of the film sidewall 2024. Alternatively, referring to FIG. 31A, the gripping openings 2140 may also be formed in the reinforcement strip 2136, in which case the reinforcement strip 2136 may advantageously extend above the top of the foil sidewall 2124 of the bag 2120.

[0138] Referring again to FIG. 28-30, slots or leads 2040 may be cut above the handle openings 2040 to aid removal of the bag 2020 from the gripper pins of the filling machine after the bag 2020 has been filled.

[0139] Grip openings 2040 may be completely eliminated if the bag 2020 is to be filled by hand or with packing equipment without gripping pins. In lieu of or in addition to the gripping holes, the top of the bag 2320 may be formed with sleeves for

ΕΡ2486178Β1 puff 2360, 2362, as seen in FIG. 31C. Each of the drawstrings 2360, 2362 of this embodiment is formed of a comparable synthetic resin film to that of the rear sidewall 2324. The sleeves may be integrally formed with the film strip 2324 and reinforcement strip 2336, respectively, or may be thermally bonded or otherwise attached to the upper ends of these straps. Each drawstring 2360, 2362 is formed by folding the extension of the associated resin strip down and out to form an overlap. A ribbon or tension strip 2364, 2366 is retained in each of the draw sleeves 2360, 2362. End portions of each drawstring 2364, 2366 are bonded or welded in associated sleeves 2360, 2362. Access to the drawstrings 2364, 2366 can be through cuts or openings (not shown) in the center portions of the drawstrings 2360, 2362 and the tapes can be drawn to close the bag 2320 at the top thereof.

[0140] The reinforcement strip 2036 may be formed from any of a variety of sheet materials. Preferably it is formed of the same material as rear sidewall 2024. Referring to FIG. 28, 29, 31, 33 and 35, the reinforcement strip 2036 has a horizontal length that is equal to the width of the bag 2020, a vertical width W, a top edge, a bottom edge and a pair of side edges. A reinforcement strip 2036 is applied to the outer surface of the top edge of the mesh strap 2034 of the bag 2020 enough to allow connection to the mesh strap 2034 through an top horizontal seam 2060 located well below the top edge of the reinforcement strip but located very close to the top edge of the mesh strap 2034. (Alternatively, it may be located between walls 2022 and 2024, in which case it will mesh with the inner surface of the mesh strap 2034). The vertical width of the overlap need not be longer than necessary to allow a proper bond to form between the reinforcement strip 2036 and the mesh sidewall 2022. Since the seams are typically in the range of an inch (1.27 cm) to% of an inch (1.0 cm), the seam width need not be significantly greater than% inch (1.0 cm) to an inch (1.27 cm). However, it should be noted that the width of the pleat can be made significantly larger without departing from the gist of the present disclosure. A wider tab allows you to print markings on the top of the mesh side of the bag. In the illustrated embodiment of a 5 pound bag for fresh vegetables and fruits, reinforcement strap 2036 extends about 5 inches (14.0 cm) above mesh strap 2034. The exposed length of mesh strap 2034 between the bottom of reinforcement strap 2036 and the top of curl 2046 is about 8 inches (20. 3 cm).

[0141] Referring again to the drawings of the bag of FIG. 28-31 and 32-35, and more particularly to FIG. 34, the mesh material used in the bag 2020 is made of both weft and warp layers of co-extruded material as described above in conjunction with FIG. 4-7. The weft fibers cross at an angle of about 25 ° -35 ° with respect to the vertical or cross machine direction, or, more typically, about 30 °. Thus, each individual fiber extends at an acute angle of about 7.5 ° -10 ° to the cross machine direction. Each diamond of 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 fibers have a "staggering" configuration as described above, with each fiber layer spacing about 8 mm apart, giving a fiber to fiber spacing of about 4 mm when viewed into the depth of the material.

[0142] Turning now to FIG. 36 and 37, a bag 2420 is shown that is constructed using an alternative mesh material that is generally the same as the mesh material described above in conjunction with FIG. 28-31 and 35. The height H, width W, and included angle a of the diamonds formed by the intersecting weft fibers are the same as disclosed in connection with FIG. 34. The alternating carcass layers of the material are spaced about 4 mm apart for most of the length of the belt when looking into the material. However, additional fibers

"2486178 "1 or threads are provided at the ends of the mesh belt 2434 at the bottom and top horizontal seams 2450 and 2460, where the mesh belt is covered and bonded to the foil sidewall tab and reinforcement strip 2436, respectively. In these areas, the number of warp yarns is doubled so that the spacing between adjacent fibers when looking into the recess of the mesh strip 2434 is reduced from about 4 mm to about 2 mm, which increases the surface area available for bonding and increases the strength of the seam at the top and bottom. mesh strap 2434.

[0143] As mentioned above in connection with the discussion of the ultra-mesh material, the angles and dimensions of the diamonds formed by the crossing weft fibers may be optimized for a desired application. To illuminate this fact, in FIG. 38 and 39 illustrate an alternative construction of bag 2520. Bag 2520 is identical to bag 2420 of FIG. 36 and 37 (including additional warp fibers in the seam areas 2550 and 2560) in addition to the fact that the weft fibers of the 2534 mesh belt material extend at a shallower angle relative to the machine direction, which gives a slightly more open mesh structure and improves visibility and ventilation, potentially reducing including seam strength. The weft fibers cross at an included angle of about 40 ° -50 ° with respect to the vertical or cross machine direction, and more typically about 46 °. Each individual filament thus extends at an angle of 20 ° -25 ° with respect to the cross machine direction. Each diamond in the pattern is about 38 to 42 mm wide, and more typically about 40 mm, and about 11 to 13 mm high, and more typically about 12 mm.

EXPERIMENTAL DATA

[0144] Several varieties or styles of multi-substrate bags have been designed and tested for various characteristics. The bags were subjected to several different tests and compared to prior art bags subjected to the same tests. The test procedures and test results will now be described in detail.

1. Drop test

[0145] The purpose of the drop test is to determine the seam strength of a bag by repeatedly dropping the bag from a given height. A bag is considered to pass the test if all of its seams survived the maximum number of drops (25 in the procedure used by the testers) without damaging any of the seams. Bags were filled with balls to the rated weight and dropped from a height of 20 inches (50.8 cm). A bag was considered to have failed the test if, after any drop, any of its seams torn or cracked more than 1 inch (2.5 cm) in length. Each style of bag was rated A to F based on the average number of drops the bag survived without seam damage. Bags which survived approximately 25 drops on average were given a rating of "A", bags damaged in the first four drops were given a rating of "F". CD scores were given in a linear relationship between the two extremes.

2. Separation test

[0146] The tear test is another, more subjective, method of testing the seam strength. Each type of seam (side, top horizontal, and bottom horizontal) is tested by manually separating the mesh and film materials of a statistically significant number of bags of each style at angles generally right or greater. If the mesh material detached relatively easily from the sheet, the bag was considered not to pass the release test. The ease of separating the sutures was assessed on the AF scale.

ΕΡ2486178Β1

3. Pull test

[0147] The pull test is used to test the overlapping seams of the top horizontal and bottom horizontal bag by manually pulling the mesh and sheet materials in opposite directions in the same plane. If the mesh material peeled off the sheet material relatively easily, the bag was considered to have failed the test. The mean ease of withdrawal of the seams for each bag style was scored on the AF scale.

[0148] The following styles of bags were tested.

Style A Bag: 10 lb. multi-substrate HDPE co-extrudate bag, 46 ° included angle

[0149] In this series, bags constructed as described above in connection with FIG. 28-31 and 32-35. The bags were sized to hold 5 pounds (2.2 kg) of articles. The mesh material of the mesh belt was a knitted ultra-mesh material generally of the type described above in FIG. 1-3, having a basis weight of 17 gsm² and consisting of two layers of co-extruded fiber warp surrounding the two layers of high density polyethylene (HDPE) weft. The diamonds formed by the weft fibers extended at angles of approximately 46 [deg.] From the vertical or cross machine direction. Each weft fiber was formed from an 80 micron thick three-layer web having a 50 micron thick HDPE layer sandwiched between two 15 micron thick LLDPE layers. The web was stretched 6: 1 to form fibers that were incorporated into the knitted fabric whereupon the composite fiber was about 0.03 mm thick and about 1.2 mm wide. The spacing between the warps of each ply was 8 mm. The fabric was an alternating fabric with the warp yarns of the bottom ply halfway from the warp yarns of the top ply, resulting in a warp yarn in the material of about 4 mm. Each fiber of the weft layer was about 0.04 mm thick and about 1.5 mm wide.

[0150] The film used to make the sheet sections of the bag was a co-extrusion film of the type described above in connection with FIG. 28-31 and 32-35. It was 1.75 mils (0.044 mm) thick.

Style B Bag: 5 lb. multi-substrate HDPE co-extrudate bag, 46 ° included angle with additional fibers

[0151] This style of bag was identical to the A style except that additional warp yarns were incorporated in the ultra-mesh area in the upper and lower side seams as discussed above in conjunction with FIG. 35 and 36. It was standard practice that the sheet side foil material of the bag and the reinforcement strip were thinner than the corresponding film section on the smaller bag having a thickness of 1.35 mils (0.034 mm).

C style bag: 10 pound multi-substrate HDPE co-extrudate bag, 46 ° included angle with extra fibers

[0152] This style of bag was identical to the B style but was a larger bag designed to hold 10 pounds (4.5 kg) of articles.

D style bag: 5 lb. multi-substrate HDPE co-extrudate bag, 34 ° included angle

[0153] This style of bag was identical to the A style except that the included angle "diamonds" were formed

ΕΡ2486178Β1 through the crossing fibers of the weft of ultra-mesh material was 34 ° from the cross machine direction. The mesh fabric had a basis weight of 20 g / m2². The warp yarns of the mesh material were uniformly spaced throughout the length of the mesh belt.

E style bag: 5 lb. multi-substrate HDPE co-extrudate bag, 34 ° included angle with additional fibers

[0154] This bag style was identical to the D style (except that the inclusion angle of the "diamonds" formed by the crossing fibers of the weft of the ultra-mesh material was 34 ° relative to the cross-machine direction), except that in the ultra-mesh material in additional warp yarns were incorporated in the upper and lower side seam area, as discussed above in conjunction with FIG. 37 and 38. The ultra-mesh fabric had a basis weight of 20 g / m2².

F style bag: 10 lb. multi-substrate HDPE co-extrudate bag, 34 ° included angle with additional fibers

[0155] This style of multisubstrate bag was identical to the style B bag, except that the bags were larger, constructed of thinner film in the film sections, and were designed to hold 10 pounds (4.5 kg) of articles.

G style bag: 5 pound multi-substrate HDPE co-extrudate bag, 34 ° included angle

[0156] This style of bag was identical to the A style except that both the warp and weft fibers of the ultra-mesh multi-substrate bag were formed from the co-extruded multi-layer material as described above in conjunction with FIG. 4-7. Both the warp and weft fibers were co-extruded 3-ply fibers of the type described above in connection with the D-style bag. The ultra-mesh material had a grammage of 19.4 g / m2.². The warp fiber spacing was 4 mm along the entire length of the mesh belt when viewed into the fabric.

[0157] The peel test, pull test and drop test for all bag styles are summarized in Table 10 below.

TABLE 10: DROPPING, SPLIT AND PULL TEST RESULTS

<td rowspan="2">Bag style</td><td rowspan="2">The size of the bag</td><td rowspan="2">Mesh type</td><td colspan="2">Top and bottom seams</td><td colspan="2">Side seams</td><td rowspan="2">Average drop to damage</td><td rowspan="2">Net weight (g / m²)</td>

<td>Separation test</td><td>Pull test</td><td>Separation test</td><td>Drop test</td>

<td>AND</td><td>10 pounds</td><td>HDPE co-extrudate / included angle 46 °</td><td>B</td><td>B</td><td>B</td><td>B</td><td> 12,8</td><td> 17</td>

ΕΡ2486178Β1

<td>B</td><td>5 pounds</td><td>HDPE co-extrudate / included angle 46 ° / additional warp yarns</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-extrudate / included angle 46 ° / additional warp yarns</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-extrudate / included angle 34 °</td><td>C +</td><td>B-</td><td>B</td><td>AND</td><td> 25,0</td><td> 20</td>

<td>E.</td><td>5 pounds</td><td>HDPE co-extrudate / included angle 34 ° / additional warp yarns</td><td>B</td><td>B</td><td>AND</td><td>AND</td><td> 23,9</td><td> 20</td>

<td>F.</td><td>10 pounds</td><td>HDPE co-extrudate / included angle 34 ° / additional warp yarns</td><td>AND</td><td>AND</td><td>AND</td><td>AND</td><td> 21,5</td><td> 20</td>

<td>G.</td><td>5 pounds</td><td>Co-extrudate Co-Ex / included angle 34 °</td><td>B +</td><td>B +</td><td>AND</td><td>AND</td><td> 24,8</td><td> 19,5</td>

[0158] The tests confirmed that acceptable seam properties were obtained for all the bags mentioned. Particularly good results were obtained with style B, C, E and F bags, all of which had additional warp yarns in the horizontal seam areas of the upper and lower ultra-mesh material. The best results were obtained with style E and F bags that had a mesh material with additional warp yarns in the top and bottom horizontal seam areas and an angle of 34 ° of intersecting weft yarns as discussed above in connection with FIG. 36 and 37.

Tensile Strength Test Results ίο [0159] The seams of bags of various styles were also tested in a tensile strength tester in order to obtain a more quantifiable seam strength test. The tensile strength tester consisted of 2 jaws 3 inches apart. Each test bag was cut into three two-inch wide strips comprising an upper horizontal seam, a lower horizontal seam, and one of the side seams, respectively. For each test, one of the strips was clamped into the jaws at its opposite ends. The jaws were then moved apart at a constant speed

ΕΡ2486178Β1 in / min (61 cm / min), mimicking the stresses exerted on bags during a rigorous filling process. The jaws were moved apart, monitoring the load on the bag until the suture was damaged. Seam damage was defined as a 20% decrease in force applied. The highest force applied to the bag prior to seam damage was recorded.

[0160] The results of these tests are summarized in Table 11 below:

TABLE 11: BLEAR TEST RESULTS

<td>Overall style of the bag</td><td>Description of the bag</td><td>Bag size (lbs)</td><td>Force for the seam (N)</td><td>Max force for the top horizontal seam (N)</td><td>Max force for bottom seam (N)</td><td>Bottom seam weight (g / m²)</td>

<td>BI</td><td>HDPE co-extrudate / included angle 46 ° / additional warp yarns</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-extrudate / included angle 46 ° / additional warp yarns (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-extrudate / included angle 34 °</td><td> 5</td><td> 20,7</td><td> 36,4</td><td> 29,1</td><td> 20,0</td>

<td>El</td><td>HDPE co-extrudate / included angle 34 ° / additional warp yarns</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-extrudate / included angle 34 ° / additional warp yarns (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-extrudate / included angle 46 °</td><td> 5</td><td> 25,1</td><td> 33,1</td><td> 25,2</td><td> 19,5</td>

[0161] Note that not all of the bag styles in Table 11 were strictly identical to the corresponding bag styles listed in Table 10. For example, the ultra-mesh material of the style labeled "HDPE Co-Extrudate / 46 ° Included Angle / Extra Fiber. Warp "(B1 style bag) had additional warp yarns in the lower horizontal seam arranged in a" stack "with the remaining fibers and not in an" staggered arrangement "as described above in connection with the B style bag. Likewise, the extra warp yarns in the ultra-mesh material of bags labeled "HDPE Co-Extrudate / Angle contained 347 additional warp yarns" (E-style bag) had additional warp yarns in the lower horizontal seam arranged "stacked" with the remaining fibers rather than in "staggering arrangement" as described above in connection with the E style of the bag.

[0162] The tensile strength tests correlated well with the drop test, tear test, and pull test, confirming that the top and bottom horizontal seams and side seams

The ΕΡ2486178Β1 of all "new bags" are more than strong enough for their original uses. All the new bags still benefited from the high dimensional stability, low weight, and high strength-to-weight ratio of the ultra-mesh material described here. These advantages include reduced carbon footprint, reduced volume for storage and transportation, and increased ventilation and visibility.

[0163] The higher dimensional stability provided by the ultra-mesh belt 2034, combined with the higher strength-to-weight ratio, contribute to the ability to form bags that have seam strength comparable to or even greater than prior art multi-substrate bags. significant reduction of the carbon footprint of bags both during production and in terms of consumption of raw materials. It also reduces the weight and volume of the bag. The reduced weight reduces shipping costs, further reducing the carbon footprint of the bags.

[0164] Tests have confirmed that the reduced volume allows for the storage and transport of a much larger number of multi-substrate bags in a given volume than comparable prior art bags. The tests compared 5-pound "new style" bags constructed in accordance with the present disclosure to 5-pound bags that were identical to these bags except that MS CLAF® mesh material was used, while the new style bags were made of ultra-mesh material. And as part of the mesh bag. Three packages of each type of bag were tested, with each package containing 250 bags. The initial or uncompressed stack height was measured in each test. A force of 27.1 N was then applied to each stack uniformly along the length of the stack, and the height was measured again. A force of 27.1 N was chosen to mimic the compression force typically exerted on a bundle of bags in the box. A total force of 42.3 N was then applied uniformly along the length of each bundle and the height was measured again. The means of the three test runs were then calculated and recorded for each style of bag. The results of these tests are summarized in Table 12 below.

TABLE 12: STABILITY OF MULTI-SUBSTRATE BAGS

<td>Mesh type</td><td>Height before exercise (cm)</td><td>Number of bags / cm</td><td>Height after pressing @ 27.1 N (cm)</td><td>Number of bags / cm</td><td>Height after pressing @ 42.3 N (cm)</td><td>Number of bags / cm</td>

<td>MSgrade CLAF®</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>Ultra- Mesh 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>

[0165] Table 12 confirms that when compressed using the force typically applied to bags when filling boxes, about 10% 40% more new style bags can be stored and transported in a given volume than comparable prior art bags using MS CLAF® as the material mesh. Multisubstrate bags are typically shipped in boxes that contain four packets in each box. The improved stackability of bags made in accordance with this disclosure allows a fifth bundle of bags to be added to each box, reducing shipping costs and the carbon footprint of the bags.

ΕΡ2486178Β1

[0166] The relatively open nature of the mesh material also greatly increases the ventilation and visibility of the stored items.

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