A new gusseted self-opening style bag with a unique bottom construction is disclosed, the bag manufactured via a new manufacturing process.
The statements in this section merely provide background information related to the disclosure and do not necessarily all constitute prior art.
The prior art includes a bag known as an SOS bag. Opinions differ on what SOS abbreviates, though it is commonly considered an abbreviation of Self Opening Style. Other interpretations of SOS include Self Opening Sack, Self Opening Square, and Self Opening Satchel. Regardless, an SOS bag as described herein is generally understood to be a gusseted bag including front and back panels joined by gussets, where the bag may be opened from a flat folded orientation to reveal a substantially flat rectangular bottom. When the bag is opened, the gussets may be unfolded and serve as side walls that, in conjunction with the front and back panels of the bag, as well as the rectangular bottom, define the general structure of the bag. A ubiquitous SOS bag of the prior art might include, by way of illustrative example, a simple single-layer brown paper lunch sack.
In the packaging industry, it is common for the top of the SOS bag to be filled with consumer goods, followed by the closure of the top of the bag to contain the goods. This closure can be done in a variety of manners, including applying adhesive or other seal to the top of the bag and rolling the bag closed to complete a top seal of the bag. In other applications, a reclosure apparatus, such as a resealable zipper profile with complementary interlocking features or a hook and loop type reclosure mechanism, for example, may be mounted atop the bag. In other applications, a heat or ultrasonic seal could be applied across the top of the bag.
Rectangular bottom, gusseted bags made substantially of plastic material exist in the art, though those bags are substantially distinct from the bags of this disclosure, specifically in that they are not traditional SOS bags. For example, some rectangular bottom gusseted bags of the prior art, such as those manufactured on box pouch machines, are not made from a gusseted tube. Rather, they are from one or more webs of material that are folded and sealed together into the general shape of a bag. These prior art bags are folded, heat sealed, and then trimmed to give flush edges around the folds and seams of the gussets, side walls, and bottoms, creating substantial waste. One of skill in the art will appreciate the numerous distinctions between a patch-style bag and a bag that will be disclosed herein.
This section provides a general summary of the disclosure, and is not intended to provide a comprehensive disclosure of its full scope or all of its features.
This disclosure includes method of manufacturing a new SOS bag including, as a preliminary step, providing a gusseted tube of indefinite length. In a series of steps, the gusseted tube may be cut, trimmed, folded, and sealed to create a unique bottom for an SOS bag. The bottoms of the front panel and the rear panel may be cut so as to permit the inward folding of the bottoms of the gussets of the gusseted tube, such that the bottoms of the gussets overlap. A front panel of the gusseted tube may then undergo a trimming and folding and heat sealing, followed by the rear panel of the gusseted tube undergoing a trimming and folding and heat sealing. Other sealing mechanisms and a variety of bag material constructions are disclosed.
The disclosure additionally includes bags manufactured by the method disclosed herein, as well as SOS bags having the unique construction disclosed herein.
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
The following description of various embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or its uses. Areas of applicability will become apparent from the description provided herein.
A new SOS bag with a unique bottom closure, as well as a method of making the same, is disclosed. A typical SOS bag 100, as seen in
A bag of the disclosure may be constructed from a gusseted tube of material of indefinite length.
The tube, and hence the bag, may be constructed of a variety of materials, including but not limited to a multi-layer construction. A multi-layer construction, for example, may include plastic film on the inner-most layer on the inside of the bag. Other layers may include printed paper, such as printed clay coated paper, one or more additional film layers, including an exterior film layer, a kraft paper layer, and a variety of other layers of material. Various other layers known to those of skill in the art of construction of multi-layered bags may be implemented to make a bag as disclosed herein.
Where the multi-layer construction includes an inner plastic film layer and a middle paper layer, those layers may be adhered together via a hot melt adhesive. Where the multi-layer construction includes an outer plastic film layer and a middle paper layer, those layers may also be adhered together via a hot melt adhesive. Where the SOS bag is multi-layered, the layers may themselves be adhered together in a variety of manners, including a flood coat of hot melt adhesive between the layers.
In an embodiment, a film layer may be adhered to any adjacent layer via laminating the film to said layer. For example, an inner plastic film layer may be laminated to a middle clay coated paper layer, and an outer film layer may be laminated to said middle clay coated paper layer.
The tube may, in an embodiment, be a single layer of plastic material, or alternatively a web of multi-layered plastic may be laminated together to form an effectively single ply such that the individual layers are not distinguishable or separately manipulable. This is distinct from the, for example, multi-layered construction that includes an inner plastic film layer, a middle kraft paper layer, and an outer printed clay coated paper layer, where each of those layers is still recognizable and distinct, and might be at least partially independently manipulated via bag manufacturing machinery.
In an embodiment of an effectively single ply plastic laminate, an inner layer of woven oriented polypropylene may be laminated to an outer layer of reverse printed oriented polypropylene to make an effectively single layer web of material. Reverse-printed is understood to mean a substantially transparent or translucent plastic film that has been printed with backwards text and/or imagery that is visible through the plastic film such that the text and/or imagery is legible, i.e. not backwards, when viewed from the side of the film opposite from where it has been printed. Alternatively, an inner non-woven plastic film layer and an outer reverse printed plastic layer may be laminated together to form an effectively single layer web of material. Additionally, a single ply of plastic film may be used to make a bag as disclosed herein. Where heat seals are used, as opposed to seals effected via glue or hot melt adhesive, a plastic-to-plastic bond may be used, where one plastic film or layer would be bonded to an adjacent plastic film or layer.
These non-limiting examples and others are fully embraced by the scope of this disclosure as the construction material into which a bag of the disclosure is made by the methods disclosed herein.
The gusseted tube of indefinite length into which a bag of the disclosure may be made can be created in a variety of ways. In an embodiment, a substantially continuous sheet of material having a consistent width and an indefinite length may be fed along a machine and by its length and manipulated and folded onto itself across its width to create an overlap of material. At the overlap, the material may be sealed to itself to create a tube of material. This folding may include folding to create gussets that run the length of the material to create the gusseted tube, where the folding of the gussets may happen before, after, or in substantial synchronization with the sealing of the material.
Where the sheet of material is fed along a machine, the material may be fed, for example, from a spool of material, or from an apparatus that creates plastic sheeting from raw plastic materials such as pellets. Or, in another embodiment, the material may be fed from a series of spools and laminated together to turn a multi-layer construction into an effectively single layer construction.
In an alternative embodiment, the material may be cut into planar segments of material of substantially equal lengths and then folded and sealed along an overlap to create side seams as individual tube portions, as opposed to being sealed along an overlap in a sheet of indefinite length which is then separated into individual tube segments.
Although hot air sealing has been described, other sealing mechanisms may be used at various points of the manufacture of the bag of the disclosure. For example, ultrasonic sealing, also known as ultrasonic welding, is a method of applying high-frequency ultrasonic acoustic vibrations to a substrate to create a solid-state weld between two surfaces. This can be done selectively via an ultrasonic horn in combination with an anvil and wheel as the substrate moves in a lateral direction past the ultrasonic welding station. In another embodiment, a conventional heat bar may be used in some instances. A heat bar may be a heated element, often in the shape of a linear mass, such as a bar, to apply heat directly to a surface, thereby causing a brief molten state to a plastic material. In either instance, pressure in the form of, for example, a rolling mechanism could be used to press two surfaces together when one or more has received a sealing application to provide a snug seal between the surfaces. In another embodiment, a hot melt adhesive may be used to seal two surfaces, where a hot melt is an adhesive applied between surfaces that may then be pressed together. These and other mechanisms known in the art for sealing two surfaces of material are embraced by this disclosure.
Bags of the disclosure are manufactured in part via a new bottom closure process that will be described hereinafter. However, the top of the bag may vary based upon the desires of the bag customer. The bag customer may be a dog food manufacturer, for example, who might want the top of the bag in one type of configuration or another. A flush cut bag is understood to mean a bag where the upper edges of the bag are substantially flush. In a flush cut bag, where the SOS bag is open and resting with the bottom of the bag on a horizontal surface, the upper edges of the bag generally define a horizontal plane parallel to the bottom of the bag. A step cut bag, by comparison, includes a first panel of a first height, gussets of a second height slightly shorter than the first panel height, and a second panel of a third height, slightly shorter than the gusset height. A Z cut bag, includes a first panel of a first height and a second panel of a second height, where the transition between the two panels along the gussets is a single diagonal cut that, when the tube and gussets are folded flat, resembles a Z or backwards Z, depending on which gusset is being viewed. Flush cut, step cut, and Z cut are all known terms to those of ordinary skill in the art with respect to gusseted bags. These and other tops, including those suitable for accepting various closure and reclosure apparatuses, are all embraced by this disclosure.
The gusseted tube of
It should be understood that die cutting of the patterns seen in
Specifically, in
Gusseted tubes as described herein include a bottom end that undergoes manipulations and sealings to create the bag of the disclosure, where the top end of the tube is the location that the cut pattern of
An exemplary method of manufacturing a bag of the disclosure will now be described. In a preliminary step, a section of gusseted material as previously described herein is provided.
Turning further to the figures,
It should be noted that where the terms “front” and “rear” are used herein, these need not necessarily be the literal front or back of the bag. These terms are merely being used herein to aid in describing the various steps of making the bag of the disclosure.
As can be seen in
The two parallel front flap cuts of equal length on the bottom edge of the panel enable the inward folding of the gussets to create the gusset overlap region 246. Without the front flap cuts, the overlap region would, at its tip, create a challenge in folding of the material or perhaps a difficult physical configuration to overcome. These cuts allow the easy inward folding by eliminating any gusset overlap at the edge of the flap, were the front flat trim region 244 resides.
As a result of the gusset folding as seen in
After the folding step of
In an alternate embodiment of the fourth step, the front flap trim region 244 may be folded about the front flap trim line 256 onto the gusset overlap region 246 to create a front flap 252 that is at least slightly shorter than the length 260 of the bag. In this way, the fourth step of this embodiment of the disclosed method may be to bring the front flap down to a length 264 that is at least partially shorter than the length of the gussets and thus the length of the bag, so as to enable a folding of the flap in a manner similar to that when the front flap trim region is removed.
The second heat seal region 284 is a region of heat sealing parallel to and in the general vicinity of the rear flap fold line 240, and may be analogous to the first seal. This second heat seal region, as seen in
The third heat seal region 286 is, in an embodiment, the final region of heat sealing and is on the rear flap 254 parallel to and in the general vicinity of the rear flap trim line 270, running the length of the bottom edge 236 of the rear flap.
In a seventh step, a second heat seal is applied in the second heat seal region 284 via the previously-described hot air mechanism, for example, where the bag is being moved gusset-first in the sealing direction 274, down a machine line and a stationary hot air nozzle applies selective hot air to the second heat seal region 284 in conjunction with a folding of the rear flap 254 about the rear flap fold line 240 onto the inwardly, folded gussets 280, the gusset overlap region 246, and the previously-folded front flap 252, and a roller or other compression mechanism applies pressure to the outside of the folded rear flap to adhere the now at least partially molten plastic of the rear flap to the inwardly folded gussets and front flap.
In an eighth step, a third heat seal is applied in the third heat seal region 286 via the previously-described hot air mechanism, for example, where the bag is being moved gusset-first in the second direction 274, down a machine line and a stationary hot air nozzle applies selective hot air to the third heat seal region 286. Here, the rear flap 254 has previously been partially folded onto the inwardly folded gussets 280 and front flap 252 in the seventh step, and a roller or other compression mechanism applies pressure to the rear flap near the rear flap trim line 270 to adhere the now at least partially molten plastic of the rear flap to the inwardly folded gussets and front flap, thereby completing the construction of a bag of the disclosure.
Preferably the side seam of the gusseted tube is on the front panel and thus the front flap. This permits a clean, uninterrupted surface for display on the bottom of the bag, whereas a rear flap with a side seam running down it could create issues with printing and appearance.
The completed gusseted bag of the disclosure, as seen now from the bottom in
In an optional step, before the front flap is folded over onto the overlapped gussets and sealed thereto, the gusset overlap region may itself be heat sealed, for example by applying hot air to the overlapping bottom gusset via a hot air nozzle and compressing it to the overlapped bottom gusset via one or more rollers. In this way, in conjunction with the other seals applied in subsequent steps, the bottom of the bag may be substantially sealed for applications where a liftable material, such as flour, could be introduced into the bag and not escape around the overlapped gussets and out the sides of the bottom of the bag.
An SOS bag of the disclosure manufactured via the foregoing method will now resemble the prior art SOS bag of
In an embodiment of a heat sealing mechanism of the disclosure, each heat sealing mechanism includes a nozzle for selectively applying hot air to a portion of the material and a subsequent roller to apply pressure to push two portions of material together to create the heat seal. In this mechanism, there is a direction which the material travels, while the heat sealing mechanism remains stationary, for example as one of a plurality of stations on a manufacturing line.
Where hot air heat sealing is used, the heat applied to the substrate will vary based on several factors, including the speed of manufacture in bags per minute and the material being heat sealed. The pressure required to effectuate the heat seal by pressing the at least partially molten material onto another substrate will also be determined by the speed of manufacture of the bags, the material being sealed, and the temperature of the hot air. The specific settings for the heat, speed, pressure, etc. may be calibrated on an individual basis on each machine and will vary from one machine to another, and from one process to another. Generally, though, hot air heat sealing stations may operate at a temperature range of 100 to 1,500 degrees Fahrenheit, although to make bags relatively quickly a higher range of 500 to 1,500 degrees may be preferred. Specific tolerances will vary by machine and substrate, but can typically fluctuate 25 degrees above or below the ideal conditions for bag manufacture and still make a quality product, based on a desired bag manufacturing speed. Many modern machines can manufacture bags at a rate of 60 to 80 large bags, such as those capable of holding bulky dog food, per minute, with higher end machines producing up to 100 per minute. As the speeds increase, so will the heat of the hot air and the corresponding pressure of the rollers. With bags moving faster down an assembly line, the hot air must be increased to compensate for the reduced time of exposure of the substrate to the hot air. The same may be said for any compression rollers, which might need additional pressure as bags move faster past the hot air sealing station.
Similarly, where ultrasonic welding takes place as a part of the manufacturing process, the desired speed of manufacturing of the bags will govern the vibration frequency and pressure between the horn and anvil for each bag. Where an ultrasonic station must operate more quickly, the vibration frequency and pressure may be increased. Additionally, where the substrate demands, the specific settings of the ultrasonic welding station or stations.
It will be appreciated by those of skill in the art that the various steps disclosed herein may be conducted by machinery in one or more manufacturing machines, and those machines may include a variety of tracks, wheels, rollers, and other known bag manufacturing machine components, including mechanisms to transfer the bag along the machine from beginning to end and between individual stations, such as sealing stations. Indeed, one could manufacture a bag of the disclosure at least partially by hand, escorting the gusseted tube from one station to another, such as individual sealing machines, or by making the bag of the disclosure on one or more manufacturing machines. All possible configurations of bag manufacturing machines that could be conceived by one of skill in the art that assemble a bag of the disclosure or practice the method of this disclosure are thus embraced by this disclosure, and this disclosure should not be limited to a single manufacturing machine with only the stations described herein.
The embodiment showing the location of the rear flap cuts as near, but not at, the outer edges of the back panel, is in part due to the nature of the material from which the gusseted tube may be constructed. Plastic film, by its nature, has memory as a property. By memory, it is understood that plastic film wants to return to its original planar structure and doesn't provide the crisp, clean ninety degree folds that a paper material, for example, might provide. So where the gusseted bag is constructed of a substantially plastic material, such as for example an effectively single ply constructed by laminating an inner woven oriented polypropylene layer with a reverse printed oriented polypropylene film layer, long folds of this material will not have totally crisp ninety degree folds that retain their shape at the same level as a paper bag, such as the brown paper lunch sack discussed earlier herein. Because plastic has memory, the various folds of the gusseted tube and additionally the finished product gusseted SOS bag of the disclosure will not be sharp bends, but rather very subtle curves at the folds. Even after folding along a crease, the plastic material will try, even if only slightly so, to curve back into a plane. When folding the flat bottom display about the rear flap fold line and sealing it to complete the bottom of the bag, having the outer edges of the bottom display flush with outer edges of the bottom of the bag might not result in as effective of a seal because of the memory of the plastic at those bends of the gussets into the bottom of the bag. The die cut outer edges of the flat bottom display in that instance might not adhere to the rest of the bottom of the bag while the folded plastic is attempting to return to a planar shape. Instead, by having the rear flap cuts near, but not at, the outer edges of the back panel of the tube, the outer edges of the bottom display may be tightly sealed against the bottom of the bag, resulting in a more complete seal. Ideally, in order to achieve the largest display area possible, one would like to have the rear flap cuts align with the folds that separates the bottoms of the gussets from the back panel, but plastic memory prevents this level of efficiency.
Thus a method of manufacturing a new flat bottom SOS bag has been disclosed, including the preliminary step of providing a gusseted tube of indefinite length. In a first step, the bottom of the gusseted tube may be cut on the bottom of the front and back panels to provide two parallel front flap cuts of equal length, near the center of the width of the panel, and two parallel rear flap cuts of equal length near the outer edges of the panel. In a second step, the gussets are inwardly folded towards each other into the interior of the tube to at least partially overlap. In a third step, the gusseted tube is presented to a sealing apparatus in a T shape in a sealing direction, the tube having a front flap and a rear flap. In a fourth step, a portion of front flap maybe cut off or folded. In a fifth step, a heat seal may be applied to a first heat seal region on the front flap in conjunction with an inward folding of the front flap. In a sixth step, a portion of the rear flap may be cut off or folded. In a seventh step, a second heat seal may be applied to a second heat seal region on the rear flap in conjunction with an at least partial inward folding of the rear flap. In an eighth step, a third heat seal may be applied to a third heat seal region on the rear flap in conjunction with the completed inward folding of the rear flap.
Additionally, a new SOS bag is disclosed. Bags of the disclosure may include a gusseted bag having a front and back panel joined by gussets, where the bottom of the SOS bag includes a pair of inwardly folded gussets, and inwardly folded front and back flaps to create a folded bottom. The bags disclosed herein may have a substantially rectangular flat bottom rear flap heat sealed to the inwardly folded front flap and inwardly folded gussets at the bottom of the bag. The gussets may overlap beneath the front flap and rear flap. The front flap and/or rear flap may be trimmed and/or cut to bring them into a length less than that of the gussets. A bag may include a plurality of heat seals about the bottom of the bag closure, including a series of substantially parallel hot air seals between the front flap and the inwardly folded gussets, and/or the rear flap and the inwardly folded front flap and/or gussets.
Bags of the disclosure provide several advantages over conventional bags of the prior art. For example, in the packaging of pet food, bags of the disclosure have various specific benefits. Pet food, including dry dog food, can be a greasy and heavy product. In the past, the packaging industry had embraced the use of paper-based or paper composite bags for dog food. However, at as the size of the bag, and thus the weight and volume of the dog food contained therein, increased, consumers and retailers were met with more frequent failures of the bag integrity, resulting in loss of product, mess in the retail environment, and negative consumer experiences.
As the industry shifted away from paper-based bag construction, woven oriented polypropylene became more favored, due to its substantially improved strength, particularly its resistance to puncture. Dog food became increasingly stored in bags constructed of a ply of woven oriented polypropylene (OPP) laminated with a layer of reverse printed plastic film, with the woven OPP on the inside of the bag against the food. These bags, by virtue of the construction material, in some instances provided less flexibility and less opportunity for attractive printing. Many of these large woven OPP were rolled and heat sealed on the bottom, which did not provide an attractive or particularly useful area for the dog food company to print. Large, heavy bags of pet food (or other goods) tend to lay on their sides in a retail environment, giving increased value to the bottom of the bags for printing.
Bags of the present disclosure, however, attempt to overcome the failures of the art. Bags disclosed herein allow the printing of logos and other information to attract consumers on the bottom of the bag in a clean, consistent manner on a substantially congruent surface. Bags can be stored laying down with the bottom-out and facing consumers, allowing for more product to be stored on shelves. Additionally, the rectangular bottoms of the bags, paired with the gusseted shape of a traditional SOS bag body, will allow tighter stacking of bags of product, both on top of each other and in adjacent columns of product. These and other advantages associated with the bags of the present disclosure will be apparent to those of ordinary skill in the art.
Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context.
When introducing elements or features and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention as well as all equivalents thereof.
This application claims priority to co-pending U.S. provisional patent application 62/405,396, filed on Oct. 7, 2016.
Number | Date | Country | |
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62405396 | Oct 2016 | US |