POUCH HAVING CONCAVELY-CURVED CORNERS
A pouch has a sheet containing at least one layer of a film material. The sheet forms a tube that is closed with a seal to form a volume. The seal contains a first edge and the sheet contains a second edge in connected relation to the first edge. A curved seal joins the first edge with the second edge. A sealing jaw and a method for forming such a pouch is also described.
The present invention relates to pouches. Specifically, the present invention relates to sealed pouches formed from a film material.
BACKGROUND OF THE INVENTIONPouches are typically formed of a laminate or a film and may be used for holding many types of items such as food, shampoos, detergents, medicines, etc. In order to prevent them from leaking, they are often sealed on all sides to form a fixed volume to contain a product, for example a granular or liquid detergent. However, it is always a challenge to balance pouch waste and strength against bursting and leakage. The strength of a seal is directly proportional to the sealing area itself. If the pouch is sealed with too much sealing area on the sides, then the given volume per area of film is smaller, leading to wasted film. However, if the sealing area is too narrow, then the pouch will easily burst if dropped or if jostled against other pouches during shipment or display.
Typically a pouch is sealed with a straight seal forming approximately a 90° angle. While this is an efficient means of sealing the top and bottom, it has now been found that this leads to easy puncture of the pouch's body in response to a sudden impact, such as when the pouch is dropped, when something else is dropped onto the pouch, etc. Such a sudden impact could occur at any time prior to opening for use, such as during the filling/manufacturing process, shipping, storage, transportation, display, etc. Such an undesirable puncture leads to waste, messiness, product loss, etc. and in some cases, a customer may even refuse to purchase a product in a punctured pouch.
Existing methods to solve this problem employ stronger sealing techniques and adhesives, stronger films and pouch materials, and/or different laminate layers within a film material. However, all of these methods typically increase complexity, and require special capability beyond that available at the machine where the forming, filling and sealing takes place.
Accordingly, the need exists for an improved pouch which is more resistant to punctures, especially while employing existing film materials, sealing processes, and sealing machinery.
SUMMARY OF THE INVENTIONThe present invention relates to a pouch having a sheet containing at least one layer of a film material. The sheet forms a tube that is closed with a seal to form a volume. The seal contains a first edge and the sheet contains a second edge in connected relation to the first edge. A curved seal joins the first edge with the second edge.
A sealing jaw contains a sealing arm and a receiving arm. The sealing arm contains a sealing area further containing a first edge-forming element and a curved seal-forming element adjoining the first edge-forming element. The first edge-forming element forms a curved seal adjacent to the first edge-forming element.
A method for sealing a pouch includes the steps of providing a sheet, forming a tube from the sheet having a leading edge, sealing the leading edge to form a leading edge seal, filling the tube with a predetermined amount of a product, sealing the tube to form a trailing edge seal, and cutting the tube after the trailing edge seal to form a pouch. The leading edge seal and the trailing edge seal form a volume therebetween and the volume contains the product. At least one of the leading edge seal or trailing edge seal contains a first edge and a curved seal adjoining the first edge.
It has now been found that the invention can significantly reduce puncturing at the body by blunting the force when, for example, the filled pouch is dropped or jostled against other pouches during shipment or display.
While the specification concludes with claims particularly pointing out and distinctly claiming the invention, it is believed that the invention will be better understood from the following description of the accompanying figures in which like reference numerals identify like elements, and wherein:
The figures herein are not necessarily drawn to scale.
DETAILED DESCRIPTION OF THE INVENTIONAll temperatures herein are in degrees Celsius (° C.) unless otherwise indicated. As used herein, the term “comprising” means that other steps, ingredients, elements, etc. which do not adversely affect the end result can be added. This term encompasses the terms “consisting of” and “consisting essentially of”.
As used herein, the term “fabric enhancer” includes a composition intended to provide an improved scent, softness, anti-static benefit, and/or shape-retention benefits to a fabric, such as a fabric conditioner, and/or a fabric softener. Such a fabric enhancer is typically intended to function in the rise cycle of a laundering process.
This disclosure relates to a pouch having a sheet containing at least one layer of a film material. The sheet forms a tube that is closed with a seal to form a volume. The seal contains a first edge and a second edge adjoining the first edge. The first edge forms a curved seal with the second edge. This disclosure also relates to methods and equipment for making such a pouch.
Referring to the Figures herein,
The film material may also be affixed to and/or contain a metal therein, and/or be a metalized film. Film materials are well known in the art and may further contain resins, laminates, printed artwork, additives (i.e., UV blockers, antimicrobials, dyes, pigments, etc.), etc. Suitable film materials are available from various suppliers worldwide such as 3M Company (St. Paul, Minn., USA), Du Pont Co. (Wilmington, Del., USA), Toppan Insatsu Co. (Tokyo, Japan), Gelman Sciences Company (Ann Arbor, Mich., USA), and many other suppliers worldwide. The sheet herein may contain either a single layer or contain multiple layers of the same, or different film material(s), so long as it remains sealable. The sheet is typically from about 15 μm to about 220 μm, or from about 20 μm to about 200 μm, or from about 25 μm to about 160 μm thick. Each individual film material may be oriented, or random as desired.
Multiple layers of film materials may be joined together to form a sheet with multiple properties and/or benefits. In such cases, it is known in the art to join the multiple layers together by, for example, lamination, heat sealing, ultrasonic sealing, gluing, pressure sealing, etc.
The sheet, 120, may then be formed into a pouch, 100, by pulling and/or stretching the sheet, 120, around a forming tube (not shown) to form a tube out of the sheet, 120. The tube is formed by sealing the edges of the sheet, 120, in any direction such as the machine direction at any point or continuously, and/or by sealing the edges in the cross direction at either the leading edge and/or the trailing edge. The forming tube doubles as a filling tube, through which the product to be contained in the pouch is then filled into the tube (see
Thus, in
In
Without intending to be limited by theory, it is believed that typical pouches contain a right angle, or even an acute angle at the corners where the leading edge seal and/or the trailing edge seal meets the edge of the standard pouch (see,
These multiple, high-velocity impacts may weaken the film material and/or even cause the body or surface taking the impact to burst. Thus, even though the individual granules are themselves quite light, the cumulative impacts to the material in the corner potentially result in a tearing of the film from within, and cause the film material at the pouch body to fail, resulting in a pouch that leaks from the body.
In contrast, the pouch herein contains a corner area, 134, where the sheet, 120, is sealed with a curved seal, 132. Without intending to be limited by theory, it is believed that the curved seal blunts the force of the plurality of moving granules. It is also believed that the curved seal distributes this force over a greater area, instead of concentrating it like a right or acute angle may do. As a result, the film material maintains its integrity and is less prone to bursting or failure. A typical pouch has approximately a rectangular or square 2-dimensional face, and therefore the pouch edges, 136, will still typically form right angles, β. Such pouches (see also
In
The product (not shown) to be filled into the pouch typically has a bulk density of at least 250 g/L, or from about 300 g/L to about 1.3 kg/L, or from about 450 g/L to about 1.1 kg/L. In one aspect, the product is typically a granular product; or a fine granular product, such as a granular product having a number-median particle size of from about 10 μm to about 5 mm. In an embodiment herein, the fine granular product is a granular detergent, a granular fertilizer, a granular fabric enhancer, a granular mineral, and/or a granular medicine; or a granular laundry detergent, and/or a granular fabric enhancer. In another aspect, the product is a liquid product. The term “liquid” is used herein to broadly include, for example, mixtures, solutions, dispersions, emulsions, etc. The liquid may be from low to very high viscosities including gels and pastes, such as up to about 10,000 mPa·s, or from about 100 mPa·s to about 1000 mPa·s, or from about 300 mPa·s to about 500 mPa·s. The liquid may contain active ingredients suitable for various applications such as, for example, domestic and consumer products (e.g., laundry cleaning and treatment, dish and hard surface cleaning, shampoo, bath additives, etc.). In an embodiment herein, the liquid product is a liquid laundry detergent, or a liquid fabric enhancer.
The volume, 144, may be either airtight or may allow air to flow into and or out of the volume, 144. In an embodiment herein the volume is airtight (or substantially airtight) once all the seals are formed and in place; only upon puncture thereof is air and/or the granular or liquid product easily let into or let out of the volume. Such an airtight pouch is typical of current bags containing, for example, a granular laundry detergent, as described in the examples. In another embodiment herein, the pouch may allow air to pass out of the volume, by, for example having a valve, a seal design allowing air to pass therethrough (see, e.g., US Patent Publication No. 2009/226573 A1 to Gonzales, et. al., published on Sep. 10, 2009), and/or having small holes purposely formed into the pouch. However, in such cases, air typically can escape from the volume only relatively slowly, and therefore the puncturing problem at the corners due to a sudden impact still exists. Without intending to be limited by theory, it is believed that in pouches where air is allowed to quickly exit the pouch, then the bursting and/or puncturing problem does not significantly exist.
The volume typically ranges from (when sealed) at least 500 mL, or from about 500 mL to about 100 L, or from about 800 mL to about 60 L, or from about 1 L to about 30 L, or from about 1.5 L to about 20 L. Typically the pouch will contain both the product as well as air (or another type of gas) therein, because without air in the package (i.e., a vacuum-packed package), the product does not move, and therefore problem does not exist. Thus, in an embodiment herein, the pouch comprises air therein, and the product in the pouch is not vacuum-packed.
Similarly,
In the embodiment of
In
In an embodiment herein, a plurality of sealing jaws may be used such that, for example, a sealing jaw may be present to seal the top of the pouch and cut it away, while a separate but adjacent sealing jaw may simultaneously seal the bottom of the next pouch.
The sealing arm, 150, also contains optional sealing ridges, 162, which may provide textured seals. Such textured seals may be desirable in some instances to produce, for example, an easier to grip seal, to enhance seal strength, aesthetic reasons, etc.
In an embodiment herein, the sealing jaw is designed so that it can cut a handle in the seal by, for example, including a handle cutting element. Such a handle cutting element may also be formed by, for example, one or more cut blades.
In an embodiment herein, the cut blade(s) is releasably attached to the sealing arm, so that when it wears out it may be removed, sharpened and/or replaced without having to fabricate an entire new sealing arm.
The sealing arm, 150, the receiving arm, 170, or both actively interact to form the seal by, for example, heat sealing, ultrasonic sealing, pressure sealing, etc. as desired, and therefore contains the appropriate sealing technology therein or thereupon, such as, for example, a heater, an ultrasonic generator, a pressure clamp, etc. The sealing arm and the receiving arm are typically each independently formed of an appropriate durable material for their uses herein, such as, for example, a metal, a ceramic, a plastic, and a combination thereof. A sealing jaw intended for heat sealing should be both strong and conduct heat well and may be formed of, for example, copper, brass, steel, or iron, aluminum, etc. Impulse and induction sealing methods are known in the art and are useful herein. Based on this disclosure, a sealing arm and a receiving arm according to the present invention may be custom made by various suppliers and/or machine shops around the world.
One skilled in the art will recognize that the sealing jaw herein may be used on an autopacking machine.
In an alternate embodiment (not shown) a single curved seal having the same center and radius also forms both the curved seal of the leading edge and the trailing edge.
In an embodiment herein the invention is combined with additional techniques known in the art, such as a laser-cut, a half-cut, a score line, embossing, etc. and the known methods and machinery therefor. In an embodiment herein, a reclosing technology is combined with the invention herein, to allow easy and efficient reclosing of the pouch after opening. Such reclosing technologies are also especially beneficial with larger-sized pouches. Typical reclosing technologies are known in the art and include plastic pressure-sensitive zippers, hook and loop fastening systems, zipper systems, adhesive strips and patches, clips and snaps, locking systems, etc. For additional technologies useful in combination with the present invention, see, EP Patent No. 1 409 366 B1 to Camargo-Parodi, et al., granted on Jun. 21, 2006; and EP Patent Application No. 07119454.2 To Rogers, filed on Oct. 29, 2007.
Example 1Pouches according to
Comparative pouches according to
Bursting was tested by dropping individual bags from a height of 1.2 m 3 times on three different sides and then also by dropping then from a height of 1.2 m 3 times packed in poly woven bags on 3 different faces. The bag was also dropped on another bag keeping the corner landing on the face of the other bag lying on ground. The observations were also made when one bag free falls from conveyer belt height to the Poly woven bag at the end of line.
The number of ruptures at the volume corners of the bags were counted, and divided by the number of total bags to determine the defect rates shown below:
The ability of the pouches of the invention to reduce quality defects during shipping was also tested. Here, the pillow pouches of
The pouches of the invention demonstrated reduced quality defects during shipment in comparison to the standard pouches with substantially 90° angles volume corners.
One skilled in the art would understand that the minor differences in the materials between the Example and the comparative pouches would not significantly affect the results of these tests. Given the unexpectedly significant reduction in rupturing.
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.”
All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. 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
1. A pouch comprising:
- a. a sheet comprising at least one layer of a film material, the sheet forming a tube; and
- b. a seal forming the tube into a volume,
- wherein the seal comprises a first edge, wherein the sheet comprises a second edge in connected relation to the first edge, and wherein a curved seal joins the first edge with the second edge.
2. The pouch according to claim 1, wherein the curved seal forms a volume corner, and wherein the pouch comprises a plurality of volume corners.
3. The pouch according to claim 1, wherein the pouch is formed by an autopacking machine.
4. The pouch according to claim 1, comprising a granular product therein.
5. The pouch according to claim 1, comprising a liquid product therein.
6. The pouch according to claim 1, wherein the film material is from about 15 μm to about 220 μm thick.
7. The pouch according to claim 1, wherein the curved seal has a radius of curvature of greater than about 3 mm, preferably from about 10 mm to about 30 mm.
8. The pouch according to claim 1, wherein the volume is substantially airtight.
9. The pouch according to claim 4, wherein the granular product is a granular laundry detergent.
10. A sealing jaw comprising:
- a. a sealing arm comprising a sealing area, the sealing area comprising: i. a first edge-forming element; and ii. a curved seal-forming element adjoining the first edge forming element; and
- b. a receiving arm,
- wherein the sealing arm and the receiving arm are complementary and wherein the sealing arm and the receiving arm may interact to seal a sheet therebetween.
11. The sealing jaw of claim 10, wherein the sealing arm comprises a heating element.
12. The sealing jaw of claim 10, wherein the receiving arm comprises a heating element.
13. An autopacking machine comprising the sealing jaw according to claim 10.
14. A method for sealing a pouch comprising the steps of:
- a. providing a sheet;
- b. forming a tube from the sheet having a leading edge;
- c. sealing the leading edge to form a leading edge seal;
- d. filling the tube with a predetermined amount of a product;
- e. sealing the tube to form a trailing edge seal; and
- f. cutting the tube after the trailing edge seal to form a pouch comprising a volume between the leading edge seal and the trailing edge seal, wherein the volume comprises the product,
- wherein at least one of the first seal or the second seal comprises a first edge and a curved seal adjoining the first edge.
Type: Application
Filed: Jan 10, 2012
Publication Date: Jul 11, 2013
Inventors: Gautam BHATTACHARJEE (Beijing), Zhe Ma (Beijing)
Application Number: 13/346,990
International Classification: B65D 30/10 (20060101);