WO2019084745A1

WO2019084745A1 - Side-gusseted pouches

Info

Publication number: WO2019084745A1
Application number: PCT/CN2017/108474
Authority: WO
Inventors: Jiashao RONG
Original assignee: The Procter & Gamble Company
Priority date: 2017-10-31
Filing date: 2017-10-31
Publication date: 2019-05-09
Also published as: CN111212791A; CN111212791B

Abstract

A side-gusseted flexible pouch (1) comprises opposing first and second lateral sides (13, 33). A first upper gusset seal (7) is disposed on the first lateral side (13) and a second upper gusset seal (35) is disposed on the second lateral side (33). A first lower gusset seal (17) is disposed on the first lateral side (13) and opposes the first upper gusset seal (7) , and a second lower gusset seal (37) is disposed on the second lateral side (33) and opposes the second upper gusset seal (35). At least one discrete area of UV-cured coating (11, 15) is coated proximate at least any one of said gusset seals (7, 17, 35, 37) on the first or second lateral sides. The side-gusseted flexible pouch having a cured coating proximate one or more of the gusset seals may have improved pouch drop test performance.

Description

SIDE-GUSSETED POUCHES

FIELD OF THE INVENTION

The present invention relates to side-gusseted pouches with improved pouch drop test performance.

BACKGROUND OF THE INVENTION

In the case of pouches made from a single sheet of film, or a laminate (i.e., two or more films) , the structure of the pouch is such that it does not expand during filling but has a generally similar shape and configuration, when empty or full. To increase the available space for filling, it is common to have pouches with side-gussets along both its longitudinal sides, connecting the front and back sides of the pouch. Gussets allow the front and rear surfaces to expand away from each other when the pouch is filled. The gusset structure is advantageous, since it permits the unfilled pouch to be substantially flat when empty, and then to expand to a full depth as the pouch is filled with product. A (vertical) form-fill-seal machine is an approach to make such gusseted pouches.

One of the problems of side-gusseted pouches is that when such pouches are filled, especially with product such as laundry detergent powders of a relatively large weight (e.g., 1-4 kg) , it is commonly observed that the pouches can show an un-acceptably high rate of failure in the “pouch drop” test. In this test, filled pouches are dropped from a pre-determined height to the ground, and checked to assess whether any seal of the pouch fails because of the impact. The areas of concern are the four inner corners of the pouches. In these corners, due to the gussets, four layers of the film/laminate come together to be sealed. It is generally believed that the reason for failure lies in the difficulty to ensure a cohesive seal between the four layers. In addition, there is a lot of stress that gets generated at these inner corners which leads to rupture (failure) . From a commercial point-of-view, it is preferred that the rate of failure is less than 5 ％, preferably less than 1 ％, more preferably less than 0.5％, even more preferably less than 0.1％. Some attempts have been carried out in the past to solve this problem. One approach is to use a thicker film or laminate. Another solution is to use an extra fold at the gusset part which requires additional film material. However, these are generally not cost-effective solutions.

There is a need for side-gusseted pouches with improved pouch drop test or drop dart test performance, and to do so cost effectively without the need to provide thicker film or laminates while minimizing any changes to standard form-fill-seal machinery and while maintaining high speed manufacturing operations.

SUMMARY OF THE INVENTION

The present invention is based, in part, on the observation that one of the sources of stress of the inner corners of side-gusseted pouches is during the vertical form-fill-seal (VFFS) processes. Specifically, in the VFFS process, specifically the side-gusset seal forming stage, gusset forming elements are thrust into what will become the lateral sides of the pouch. Surprisingly it is found that the use of UV-cured coating at the point of impact of these gusset forming elements (into what will become the lateral sides of e the pouch) helps to reduce a negative influence in the integrity of the gusset seals and thus may improve pouch drop test performance. The UV-cured coating that is coated proximate to any of said gusset seals on the first or second lateral sides helps to solve this need.

An aspect of the invention provides a side-gusseted flexible pouch (having improved pouch drop test performance) . The pouch comprises opposing first and second lateral sides. A first upper gusset seal is disposed on the first lateral side and a second gusset seal on second lateral side. A first lower gusset seal is disposed on the first lateral side and opposes the first upper gusset seal. A second bottom gusset seal is disposed on the second lateral side and opposing the second upper gusset seal. At least one area, preferably discrete area, of coating, preferably UV-cured coating, is proximate to any one or more of said gusset seals on the first or second lateral sides.

Another aspect of the invention provides for a method of making a side-gusseted flexible pouch comprising the steps: flexographically coating a portion of a flexible film or laminate with an ultra violet light (UV) -curable coating； UV curing the UV-curable coat to form a UV-cured coating； and forming a gusset seal by contacting the UV cured coating portion of the flexible film or laminate with a gusset forming implement； to form the said-gusseted flexible pouch.

One more advantages of the provided curable coating herein may include providing a film or laminate that is not too stiff as to cause unsightly wrinkles in the pouch (especially given the high-speed conditions typically associated with VFFS machines) , leveraging the use of standard VFFS machines, providing a relatively large manufacturing tolerances (typically need in a high-speed operations) , minimizing the use of coating material, using coating material that is translucent or transparent as not to be consumer noticeable and/or effect artwork associated with the pouch, using coating material that is flexible, and combinations thereof.

While the specification concludes with claims that particularly point out and distinctly claim the invention, it is believed the present invention will be better understood from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments set forth in the drawings are illustrative in nature and not intended to limit the invention defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

Figure 1 is a perspective view of a pouch having a discrete area of UV-cured coating proximate to gusset seals；

Figure 2 is a partial front view of an upper portion of a lateral side of the pouch of Figure 1；

Figure 3 is a partial front view of a lower portion of a lateral side of the pouch of Figure 1； and

Figure 4 is a perspective view of a general schematic of a VFFS machine.

DETAILED DESCRIPTION OF THE INVENTION

The following text sets forth a broad description of numerous different embodiments of the present disclosure. The description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. It will be understood that any feature, characteristic, component, composition, ingredient, product, step or methodology described herein can be deleted, combined with or substituted for, in whole or part, any other feature, characteristic, component, composition, ingredient, product, step or methodology described herein. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims.

Figure 1 describes a perspective view of a filled side-gusseted flexible pouch (1) of the present invention. The side gusseted pouch (1) comprises a first lateral side (13) and a second lateral side (33) that are opposing each other. Generally, these lateral sides (13, 33) are symmetrical to each other. A first upper gusset seal (7) is disposed on the upper end of first lateral side (13) . A second upper gusset seal (35) is disposed on the upper end of the second lateral side (33) . A first lower gusset seal (17) is disposed on the lower end of the first lateral side (13) . A second lower gusset seal (37) is disposed on the lower end of the second lateral side (33) . The first upper gusset seal (7) and the first lower gusset seal (17) oppose each other. The second upper gusset seal (35) and the second lower gusset seal (37) oppose each other. There are two discrete areas of UV-cured coating (11, 15) that is proximate to the gusset seals (7, 17) of the first lateral side (13) . Although not shown, there are corresponding two discrete areas of UV-coating on the second lateral side (33) . Referencing the first lateral side (13) , a UV-cured coating is proximate the first upper gusset seal (11) and a UV-cured coating that is proximate to the first lower gusset seal (15) are shown.

Still referring to Figure 1, the side-gusseted flexible pouch (1) has a top seal (41) and a bottom seal (43) . The top seal (41) and bottom seal (43) are opposing each other. The pouch (1) has a front side (45) and an opposing back side (not shown) . A first lateral longitudinal axis (3) is along the length (i.e., longest dimension) of first lateral side (13) and a second lateral longitudinal axis (39) is along the length second lateral side (33) .

Figure 2 is a partial front view of an upper portion of a first lateral side (13) of the pouch (1) of Figure 1. A first lateral longitudinal axis (3) is shown along the first lateral side (13) . The first upper gusset seal (7) is at the upper end of the first lateral side (13) . The outer edge of the first upper gusset seal (5) is the edge of the upper end of the first lateral side (13) . Opposing said outer edge of the first upper gusset seal (5) (of the first upper gusset seal (7) ) is an inner edge of the first upper gusset seal (29) . A first top vertical intersection (31) is formed between the intersection of the first upper gusset seal (7) and the top seal (41) (wherein the top seal (41) is not shown in FIG. 2 but is previously shown in FIG. 1) . At the juncture of the first top vertical intersection (31) and the inner edge of the first upper gusset seal (29) is the first upper inner corner (9) . It is this inner corner (9) (of any of the four) that is a potential point of weakness during the Pouch Drop Test (described below) . The inner edge of the first upper gusset seal (29) and the outer edge of the first upper gusset seal (5) are generally in a plane orthogonal to the first lateral longitudinal axis (3) . The first top vertical intersection (31) is generally formed about the mid-point of the width along the first upper gusset seal (7) , wherein the width is measured in a plane orthogonal to the first lateral longitudinal axis (3) . In other words, the first top vertical intersection (31) is a plane along the first lateral longitudinal axis (3) .

Still referring to FIG. 2, a plane along the first lateral longitudinal axis (3) (and intersecting the second lateral longitudinal axis (39) , not shown in FIG. 2 but previously shown in FIG. 1) intersects the discrete area of UV-cured coating proximate the first upper gusset seal (11) . The upper edge of the UV-cured coating (12) , closest in proximity to the first upper inner corner (9) , is at a distance preferably less than 30 mm (more preferably less than 25 mm, or less than 20 mm, or less than 15, or even less than 10 mm apart) from the first upper inner corner (9) as measured along said plane (i.e., the plane intersecting the first and second lateral longitudinal axis (3, 39) ) ； alternatively, the distance is from 0 mm to 30 mm, or from 1mm to 30 mm, or from 5 mm to 25 mm. Alternatively, although not preferred, there is no said upper edge (12) but rather the UV-cured coating area is formed as part of the first top vertical intersection (31) or first upper inner corner (9) . Preferably the subject UV-cured coating area (11) is discrete, or at least does not form part of the gusset seal, because having additional UV-cured coating beyond the area so described may interfere with gusset sealing (and negatively impact results from the pouch drop test) . Of course, increasing costs unnecessarily is another consideration.

Figure 3 is partial front view of a lower portion of a lateral side (13) of the pouch (1) of Figure 1. A first lateral longitudinal axis (3) is shown along the first lateral side (13) . The first lower gusset seal (17) is the lower end of the of the first lateral side (13) . The outer edge of the first lower gusset seal (21) is the edge of the lower end of the first lateral side (17) . Opposing said outer edge of the first lower gusset seal (21) (of the first lower gusset seal (17) ) is an inner edge of the first lower gusset seal (27) . A first bottom vertical intersection (25) is formed between the intersection of the first lower gusset seal (17) and the bottom seal (43) (wherein the bottom seal (43) is not shown in FIG. 3 but is previously shown in FIG. 1) . At the juncture of the first bottom vertical intersection (25) and the inner edge of the first lower gusset seal (27) is the first lower inner corner (19) . It is this inner corner (19) (of any of the four) that may also be a potential point of weakness during the pouch drop test (described below) . The inner edge of the first lower gusset seal (27) and the outer edge of the first lower gusset seal (21) are generally in a plane orthogonal to the first lateral longitudinal axis (3) . The first bottom vertical intersection (25) is generally formed about the mid-point of the width along the first lower gusset seal (17) , wherein the width is measured in a plane orthogonal to the first lateral longitudinal axis (3) . In other words, the first bottom vertical intersection (25) is a plane along the first lateral longitudinal axis (3) .

Still referring to FIG. 3, a plane along the first lateral longitudinal axis (3) (and intersecting the second lateral axis (39) , not show in FIG. 3 but previously shown in FIG. 1) intersects the discrete area of UV-cured coating proximate the first lower gusset seal (15) . The lower edge of the UV-cured coating (16) , closest in proximity to the first lower inner corner (19) , is at a distance preferably less than 30 mm (more preferably less than 25 mm, or less than 20 mm, or less than 15, or even less than 10 mm apart) from the first lower inner corner (19) as measured along said plane (i.e., the plane intersecting the first and second lateral longitudinal axis (3, 39)) ； alternatively, the distance is from 0 mm to 30 mm, or from 1mm to 30 mm, or from 5 mm to 25 mm. Alternatively, there is no said lower edge (16) but rather the UV-cured coating area is formed as part of the first bottom vertical intersection (25) or first lower inner corner (19) . Preferably the subject UV-cured coating area (15) is discrete, or at least does not form part of the gusset seal, because having additional UV-cured coating beyond the area so described may interfere with gusset sealing (and negatively impact results from the Pouch Drop Test) . Of course, increasing costs unnecessarily is another consideration.

Although not shown, an analogy to the second lateral side (33) of the pouch (1) is provided in accordance to FIG. 2 and 3. Preferably the UV-coating area is a discrete area. Preferably, a side-gusseted flexible pouch (1) is provided, wherein at least any one, preferably at least two, more preferably at least three, even more preferably four of the discrete areas of UV-cured coating (s) is proximate the respective gusset seal at a length less than 30 mm, preferably less than 20 mm, at a distance along a plane of the respective longitudinal lateral axis (3, 39) ； preferably wherein the discrete areas of UV-cured coating of first and/or second upper gusset seals (11, not shown) and the discrete area of UV-cured coating of first and/or second lower gusset seals (15, not shown) are each proximate to the respective gusset seals (7, 17, 35, 37) at a length less than 30 mm, preferably less than 20 mm, to the respective gusset seal along a plane of the respective lateral longitudinal axis (3, 39) . Preferably a plane intersecting the first lateral longitudinal axis (3) , more preferably a plane intersecting the first and second lateral longitudinal axis (3, 39) , intersect at least one discrete area of UV-cured coating (11 or 15) , preferably at least two, more preferably three, or four of said discrete areas of UV-cured coating (11, 15, not shown) . More preferably the first (or second) UV-cured coating proximate the first (and second) upper gusset seal (11) is discrete having a defined area from 0.5 cm² to 10 cm², preferably from 1 cm² to 5 cm², alternatively one example is 1-2 cm². More preferably the first (or second) UV-cured coating proximate the first (and second) lower gusset seal (15) is discrete having a defined area from 1 cm² to 30 cm² , preferably from 2 cm² to 20 cm² , alternatively from 2 cm² to 10 cm², alternatively from 2 cm² to 5 cm², alternatively one example is 3-4 cm².

The side-gusseted flexible pouch could have 70％, preferably more than 80％, more preferably more than 85％, yet more preferably more than 90％, of surface area of first and/or second lateral side (13, 33) is free of UV-cured coating； alternatively, from 90％to 99％of the surface of the lateral side (13, 33) is free of UV-cured coating.

UV-Cured Coating

A curable coating is coated to a lateral side of the pouch. A preferred method of coating is by way of printing, preferably flexographic printing. Spraying is another way of coating. The curable coating is cured to provide a cured coating. Use of a UV-curable coating is preferred. One example of such a UV-curable coating is from Actega Coating and Sealants (amember of Altana) under the tradename of LED-X25AL63B. Preferably the curing is by ultraviolet (UV) light to provide a UV-cured coating. LED-UV is even more preferred given considerations of cost and speed. Other methods of curing may include air drying, heat, or other forms of radiation. Preferably the cured coating is a discrete area proximate to the gusset seals of the lateral side of the pouch. The term “coating” is used broadly to include ink, varnish, coating, or combinations thereof, that is suitable for coating onto a flexible film or laminate, preferably a polymeric flexible film or laminate. Preferably the curable coating is relatively high viscosity during the coating process. For example, centipoise (cps) ranges can be 400 cps to 1500 cps, which is especially preferred during flexographic printing process (as the coating process) . This relatively high viscosity helps to enable the preferred thickness and/or preferred Actual Coat Weight ranges indicated herein. A preferred range of thickness of the cured coating is from a thickness of 10 microns to 150 microns, preferably 20 microns to 130 microns, more preferably 25 microns to 110 microns, even more preferably from 30 microns to 90 microns. One method of assessing thickness is by way using a Thwing-Albert ProGage lab based caliper measuring device that has 0.5 kPa force (consistently) . Another way to characterize the cured coating is by way of Actual Coat Weight Test. A preferred range of Actual Coat Weight of the cured coating is 10 g/m² to 50 g/m², preferably from 15 -40 g/m², yet more preferably from 18-33 g/m². The procedure to determine the Actual Coat Weight is described in the Example section herein.

Advantages of the UV-cured coating may include one or more of the following: curing speed, transparency, adhesion, flexibility, and minimization of VOC (preferably zero VOC, i.e., 100％solids) . Preferably the UV-curable coating is 100％reactive and cross-linked. Preferably the UV-curable coating is transparent or translucent (so to allow graphics etc., to show through as well as minimalizing being noticed by the user) , more preferably transparent.

A preferred way of coating is by flexographically printing the curable coating. Briefly, the UV curable coating from the supplier is pumped to curable coating container. One way of pumping is by way of a high viscosity double diaphragm ink pump. Once contained in the curable coating container, the flow and quantify of UV-curable coating dispensed to a anilox roller is controlled by a chambered reverse angle doctor blade system such as one from Printco Industries, LLC (US) . This is advantageous given the relative high viscosity of the UV curable coating. One example of an anilox roller suitable for flexographically printing the curable coating, especially one having the viscosity ranges indicated above, is from Harper Corporation of America (USA) , LaserKote^TM engraved ceramic roller in. The anilox can be trihelical in shape, having a cell count from 30-70, preferably from 40-60, more preferably from 40-50. The volume is from 38 to 90 BCMs, preferably 45 to 85 BCMs, more preferably 65 to 80 BCMs, and in one non-limiting example is 72 BCMs. The trihelical shaped engraving typically have 45° cell angles. “BCMs” are billion cubic microns per square inch of surface area, wherein 1 BCM is equal to 1.549 cm³/m². BCM volume can be measured by a system that uses reflected light to gather height information of microscope surface patterns with an accuracy in a nanometer scale (e.g., as fine as 10 nanometers) . One such approach is by Echotopography^TM by Harper Corporation of America. The anilox roller transfers the UV-curable coating to a printing plate, and the printing plate thereafter prints the UV-curable coating to the flexible film or laminate. An example of a printing plate is one from MacDermid. Preferably the printing plate has a low surface energy and high volume microcell texture.

The UV curable coating is UV cured, preferably UV-LED cured. One example of such a preferred method is utilizing a UV-LED curing system by Phoseon Technology, Inc. (US) . One example is FireLine^TM FL 400. This system has emitting window sizes from 125 mm x 20 mm to 300 mm to 20 mm. A peak irradiance at wavelength is 12 W/cm² at 365 nm and 24W/cm² at 385/395/405 nm, and is water cooled.

Pouch Making

Figure 4 is a perspective view of a system (99) for continuously forming, filling and sealing side-gusseted flexible pouches with product. The system is constructed in the form of an enclosed frame on which all parts for the forming, filling, and sealing of the pouches are mounted. In this figure, a continuous sheet of film or laminate (101) is un-wound from a roll (not shown) . The un-wound roll is coated with a UV curable coating and then UV cured to provide a UV curable coating (as described) at locations on the un-wound roll that will become proximate to the gusset seals. The un-wound roll, coated and cured with UV curable coating, is conveyed over conveying rollers (102, 103) . It then reaches a forming shoulder (104) and later on, a pouch-former (105) (also called a forming tube) . In this pouch-former, the sheet of film (101) is folded over itself so that the opposing longitudinal edges (106, 107) are juxtaposed to form a common vertical film edge. A vertical sealer (108) then seals this common overlapped vertical film edge to form a film-tube (109) . Pulling means (not shown) then continuously pulls the film-tube (109) along machine direction as set on a stroke length lever (not shown) . A pair of upper gusset forming elements (111A, 111B) (means for forming the first and second upper gussets) and a pair of lower gusset forming elements (110A, 110B) (means for forming the first and second lower gussets) , are disposed on either lateral sides of the film-tube from respective gussets on both lateral sides of the film-tube. These gusset forming elements are also sometimes referred to as gusset tuckers. These gusset forming elements strike the lateral sides of the film-tube at same locate where the UV-cured coatings are located. Without wishing to be bound by theory, these coatings provide protection against the impact of the gusset forming elements thrust into the film-tube to reduce at least one negative influence in the integrity of the gusset seal (and thus may improve pouch drop test performance) . The upper gusset forming elements (111A, 111B) are located below the sealer while the lower gusset forming element (110A, 110B) are located above a pair of horizontal sealing jaws (112A, 112B) .

The film-tube is then sealed in the horizontal direction by a pair of

horizontal sealing jaws

112A, 112B) at a predetermined location below the vertical sealer (108) . The horizontal sealing jaws simultaneously define the top (horizontal) seal (41) of the filled pouch (1) , and the bottom (horizontal) seal (43) of the pouch to be filled (2) . Perforations (120) are formed between the top seal (41) and the bottom seal (43) for later severing the filled and sealed pouches to form individual pouches therefrom. In heat-sealing system, which is used for majority of films/laminates, this severing action takes place separately, whereas in the poly heat-sealing system, the sealing and severing actions take place at the same time, because knives are mounted on the sealing jaws itself. In the pouch to be filled (2) , a product (e.g., dry laundry detergent) is continuously fed through means in the form of a tube (121) , below the vertical sealer (108) and above the pair of horizontal sealing jaws (112A, 112B) . The open end of the film-tube is then sealed with the horizontal sealing jaws, at a pre-determined location, which corresponds to a distance of one bag length. The cycle is repeated to form plurality of pouches.

Film or Laminate

The continuous sheet of film or laminate (described in Figure 4) can be made from a single layer film or a laminate made from multiple layers of film. Preferably the sheet is a laminate, more preferably the laminate is a two-layer film or a three-layer film, even more preferably a two-layer film. Polymeric films and laminates are preferred. In a two-layer laminate, the outermost layer is a printed film layer and while the inner layer is the sealing film layer. In a three-layer laminate, there is a middle film layer (in between the printed film layer and the sealing film layer) . In a laminate, the film layers are laminated together. Dry lamination, solventless lamination, and extrusion lamination are known ways of combining films to form the laminate. In an alternative example, the laminate comprises an adhesive layer adhering one or more film layers.

The printed film /middle film /sealing film (and other film layers) may have one or more layers (e.g., 1-3 layer co-extrusion blown film) . The printed film is preferably printed, more preferably reverse printed. The printed film may provide a matte or glossy finish. The printed film may be made from polypropylene, preferably uniaxially or biaxially oriented polypropylene, more preferably biaxially oriented polypropylene ( “BOPP” ) . A typically thickness of the printed film is from 10 microns to 30 microns, preferably from 15-25 microns, alternatively from 17-21 microns, or about 19 microns. The sealing film may be made from polyethylene ( “PE” ) . If the laminate is a two-layer laminate, the sealing film may have a typical thickness from 50 microns to 200 microns, preferably from 50-160 microns, more preferably 90-130 microns.

When the laminate is a three-layer laminate, typically the middle layer film is made from polyethylene terephthalate ( “PET” ) and having a thickness from 5 microns to 15 microns, preferably from 9-12 microns； alternatively, 3-7 microns or 7-11 microns. The sealing film, in the three-layer laminate, may have a thickness from 50 microns to 150 microns, preferably 90-130 microns, more preferably from 100-120 microns, yet more preferably 105-115 microns (and preferably made from polyethylene)

The overall thickness of the film or laminate can be from 30 microns to 170 microns. In a two-layer laminate, the overall thickness may be from 90 to 150 microns, preferably 95 to 135 microns. In a three-layer laminate, the overall thickness may be from 30 microns to 150 microns, preferably from 50 microns to 110 microns. One suitable way to assess thickness of films and laminates is by a ProGage^TM Thickness Tester, by Thwing-Albert Instrument Company (and in accordance to the manufacture’s instructions) .

The gusset pouch of the present invention may contain relatively large amount of product. For example, the gusset pouch of the present invention may contain from 0.25 kg to 10 kg of product, preferably from 0.5 kg to 5 kg, more preferably from 1 kg to 4 kg, alternatively from 1.5 kg to 3 kg, of product contained within the gusset bag. Non-limiting examples include 1.65 kg, 1.7 kg, and 3 kg of product. Relatively large amounts of product containable in the gusset pouch include dry laundry detergent powder.

EXAMPLES

Various gusset pouches of different laminate formulations, both comparative and inventive examples, are tested for Drop Impact Test and Pouch Drop Test results. Methods are described. Results are provided.

The Drop Impact Test is conducted according to ASTM Method D1709–04, entitled “Standard Test Methods For Impact Resistance of Plastic Film by the Free-Falling Dart Method, ” Test Method A ( “Dart Impact Test” ) . The larger the mass, the more desirable the result. The dart is dropped at the discrete area of UV-cured coating that is proximate to the first lower gusset seal (15) , or otherwise would be located in comparative pouch examples. The drop location is selected as likely the most challenging point of stress during the VFFS process as the gusset forming elements strike the lateral sides of the film-tube.

The Pouch Drop Test is conducted by taking 4-6 pouches containing in a secondary package of a polywoven bag (totaling about 10-12 kg) and dropping the polywoven bag from a height of 1.0 meter onto a flat solid surface three times. The polywoven bag is dropped along its length. Alternatively, a corrugated cardboard shipper can be used as a secondary package. After the secondary package is dropped the described three times, each of the contained pouches is inspected for any failures. These failures may include any of the four gusset seals (7, 35, 17, 37) , or top and bottom seals (41, 43, respectively) , or a puncture in the laminate itself (anywhere on the pouch) . Each type of pouch (Nos. 1-5) has ten specimens tested with the average results (i.e., pass or fail) reported. Passing results are desirable.

The Actual Coat Weight (g/m²) procedure is described. The following steps are taken: (i) Select the pouch specimen that is free of creases and defects； (ii) Environmentally condition the test pouch specimen inside the laboratory at least 24 hours prior to testing； (iii) Accurately cut pouch specimen with UV-cured coating in an area of 3 cm²； (iv) Cut specimen without the UV-cured coating, each having an area of 3 cm²； (v) Measure the weight of the specimen using highly accurate scale (e.g., 0.0001 grams) . Lastly, determine the Actual Coat Weight ( “X” ) following the equation: X＝ (W1-W2) /Ax 10⁴； wherein “W1” is measured weight of specimen with UV-cured coating (g) , “W2” is measured weight of specimen without coating (g) , “A” is the specimen area (cm2) , and “10⁴” is to convert the results to m². Table 1 summarizes the results.

Table 1: Results of Drop Impact and Pouch Drop tests between inventive example (No. 5) and comparatives examples (Nos. 1-4) are provided.

Results are discussed. Comparative example 3 and inventive example 5 have comparative Drop Impact Test results of about the same value (i.e., 856.2 g and 853.8 g, respectively) . However, inventive example 5 has a thinner inner layer of 90 microns of PE (vs. 100 microns of PE for the comparative example) . Of course, inventive example 5 has a UV-cured coating coated proximate the gusset seals. Therefore, thinner laminate may be used to save costs but still provide commercially acceptable performance. The Pouch Drop Test affirms these findings because comparative example 3 and inventive example 5 both pass. Comparative example 4, which has the same laminate formulation as inventive example 5 but does not have a UV curable coating, fails the Pouch Drop Test. This demonstrates that the subject laminate formulation is otherwise commercially acceptable for 1.65 kg containing product but for the UV curable coating coated proximate the gusset seals.

Preferably the pouches of the present invention pass the Pouch Drop Test as described herein. Preferably the pouches of the present invention have a Drop Impact Test (as described herein) results greater than 750 grams, preferably greater than 800 grams, more preferably greater than 825 grams, even more preferably greater than 840 grams.

The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm. ”

Every document cited herein, including any cross referenced or related patent or application and any patent application or patent to which this application claims priority or benefit thereof, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims

A side-gusseted flexible pouch (1) comprising:

opposing first and second lateral sides (13, 33) ,

wherein a first upper gusset seal (7) is disposed on first lateral side (13) and a second upper gusset seal (35) is disposed on second lateral side (33) ,

wherein a first lower gusset seal (17) is disposed on the first lateral side (13) and opposes the first upper gusset seal (7) , and a second lower gusset seal (37) is disposed on the second lateral side (33) and opposes the second upper gusset seal (35) ,

wherein at least one discrete area of UV-cured coating (11, 15, not shown) is coated proximate at least any one of said gusset seals (7, 17, 35, 37) on the first or second lateral sides.
The side-gusseted flexible pouch (1) of claim 1, wherein at least one discrete area of the UV-cured coating (11, 15, not shown) comprises a thickness of 10 microns to 150 microns, preferably from 20 microns to 130 microns, more preferably from 25 microns to 110 microns, even more preferably from 30 microns to 90 microns; preferably said UV-cured coating (11, 15, not shown) is translucent or transparent, preferably transparent.
The side-gusseted flexible pouch (1) of claim 1 or 2, wherein the discrete area of UV-cured coating (11, 15, not shown) comprises an Actual Coat Weight (preferably per the method described herein) is 10 g/m² to 50 g/m², preferably from 15 -40 g/m², yet more preferably from 18-33 g/m²; preferably said UV-cured coating (11, 15, not shown) is translucent or transparent, preferably transparent.
The side-gusseted flexible pouch (1) of any one of the preceding claims, wherein at least two, preferably at least three, more preferably four, of the discrete areas of UV-cured coating (11, 15, not shown) is coated proximate to each of the respective gusset seals (7, 17, 35, 37) on the first or second lateral sides (13, 33) .
The side-gusseted flexible pouch (1) of any one of the preceding claims, wherein the discrete area of UV-cured coating (11, 15, not shown) is a UV-cured flexographically applied coating.
The side-gusseted flexible pouch (1) of any one of the preceding claims, further comprising: a top seal (41) and an opposing bottom seal (43) .

wherein first upper gusset seal (7) and the top seal (41) form a first top vertical intersection (31) and the first lower gusset seal (17) and the bottom seal (43) form a first bottom vertical intersection (25)

wherein a plane along a first lateral longitudinal axis (3) intersects the first top vertical intersection (31) and the first bottom vertical intersection (25) ;

preferably wherein the plane along a first lateral longitudinal axis (3) also intersects said at least one discrete area of UV-cured coating (11 or 15) , preferably at least two of said discrete areas of UV-cured coating (11, 15) .
The side-gusseted flexible pouch (1) of any one of the preceding claims, wherein at least any one, preferably at least two, of the discrete area (s) of UV-cured coating (11, 15) proximate the respective gusset seal (s) (7, 17) at a distance less than 30 mm, preferably less than 20 mm, in plane along the first vertical lateral axis (3) .
The side-gusseted flexible pouch (1) of any one of the proceeding claims, wherein the UV-cured coating (11, 15) is proximate the first upper gusset seal (7) or the second upper gusset seal (35) is discrete and having a defined area from 0.5 cm² to 10 cm², preferably from 1 cm² to 5 cm².
The side-gusseted flexible pouch (1) of any one of the proceeding claims, wherein the UV-cured coating (15) is proximate the first (and second) lower gusset seal (17, 37) is discrete and having a defined area from 1 cm² to 30 cm², preferably from 2 cm² to 20 cm².
The side-gusseted flexible pouch (1) of any one of the proceeding claims, further containing from 0.25 kg to 10 kg of product, preferably from 0.5 kg to 5 kg, more preferably from 1 kg to 4 kg;preferably the contained product is a powder, more preferably the powder is a dry laundry detergent powder.
The side-gusseted flexible pouch (1) of any one of the proceeding claims, where the film or laminate is a laminate, preferably wherein the laminate comprises a 2-layer film or a 3-layer film.
The side-gusseted flexible pouch (1) of any one of the proceeding claim 11, wherein the laminate comprises a 2-layer film, wherein the 2-layer film comprises: a printed film of a 15-25 micron thick, preferably 17-21 microns, of a biaxially oriented polypropylene; and a sealing film of a 60-160 microns thick, preferably 90-130 microns, of a polyethylene.
The side-gusseted flexible pouch (1) of any one of the proceeding claim 11, wherein the laminate comprises a 3-layer film, wherein the 3-layer film comprises: a printed layer of a 15-25 micron thick, preferably 17-21 microns, of a biaxially oriented polypropylene; a middle film of a 9-12 microns thick, preferably 10-12 microns, of a polyethylene terephthalate; a sealing film of 90-130 microns, preferably 110 microns, of polyethylene; and wherein the middle film is in-between the printed film and the sealing film.
The side-gusseted flexible pouch (1) of any one of the proceeding claims, wherein there is a probability of least 95％, preferably at least 97％, more preferably at least 98％, even more preferably at least 99％, of the side-gusseted flexible pouch passing the pouch drop test as described herein; and

preferably the side-gusseted flexible pouch further has a drop impact test result, per the method described herein, greater than 750 grams, preferably greater than 800 grams, more preferably greater than 825 grams, even more preferably greater than 840 grams.
A method of making a side-gusseted flexible pouch (1) according to any one of claim 1-14 comprising the steps:

(a) flexographically coating a portion of a flexible film or laminate with a UV-curable coating;

(b) UV curing the UV-curable coating to form a discrete area of UV-cured coating; and

(c) forming a gusset seal by contacting the UV-cured coating portion of the flexible film or laminate with a gusset forming elements (110A, 110B, 111A, 111B) ; to form the said-gusseted flexible pouch (1) .