JP7567339B2 - Packaging Bag - Google Patents

Description

The present invention relates to a packaging bag. In particular, the packaging bag is made of a laminate with a plastic film as a base material and a sealant layer, and is capable of being easily opened by hand and having an opening for removing the contents.

Packaging bags are not only made of a single layer of plastic film, but also laminated with other plastic films, resin layers, metal foils, etc. One of the features of packaging bags is that the layer structure and material design can be tailored to the quality required by the contents, and they are used widely for a variety of purposes. In terms of both performance and cost, packaging bags are often more advantageous than glass bottles and cans.

In particular, there has been a growing movement to stop using disposable plastic and glass bottles in recent years. In addition to cost considerations, there has been a noticeable movement to reduce waste by using refillable containers from an environmental protection perspective.

For example, liquid packaging bags with a sealant layer and a plastic film base can be made into various shapes using the sealant layer, are highly flexible, and can be folded flat after use to reduce the volume. They can also be incinerated as waste.

With these advantages as a backdrop, packaging bags formed from laminates with a plastic film as a base material and a sealant layer have been highly evaluated for their functionality and convenience, and demand for them has been particularly high in recent years.

When opening such a packaging bag, one side or part of the bag can be cut with scissors or a blade to form an opening and remove the contents, but packaging bags that can be easily opened by hand without using a blade or the like are also in practical use.

For example, Patent Document 1 proposes a packaging container in which the contour of the opening is formed by a half-cut line on the side opposite the seam seal of the pillow packaging bag. However, because the protruding part of the contour of the opening is used as a trigger for the opening operation, pinching this part to create the opening is not easy and involves difficulties.

JP 2019-189291 A

The present invention was made in consideration of such circumstances, and aims to provide an inexpensive packaging bag in which an opening for removing the contents can be easily formed using fingers.

As a means for solving the above problem, the invention described in claim 1 is:
A packaging bag made of a laminate having a plastic film as a base material and a sealant layer,
The packaging bag has a longitudinally extending seam portion formed therein,
The bag is made into a pillow packaging bag by forming seals at both top and bottom ends with the joint seal portion as the bottom.
A half-cut line is provided on the top surface opposite the bottom surface from the outside of the packaging bag,
The half-cut lines are provided in a U-shape at the top of the upper packaging bag, below the upper end seal and equidistant from the left and right side ends, and extend diagonally downward to the left and right.
Furthermore, the half-cut line is characterized in that before reaching the left and right side edges, it changes direction downward and runs parallel to the side edges so as to reach the lower part of the packaging bag on the upper surface.

The invention described in claim 2 is as follows:
The packaging bag according to claim 1, wherein the half-cut line is in a V-shape with a concave apex at the apex of the V-shape.

The invention described in claim 3 is as follows:
The packaging bag according to claim 1 or 2, wherein the half-cut line changes direction downwardly of the packaging bag and then continues laterally in the left and right directions at the lower end thereof.

The invention described in claim 4 is as follows:
The packaging bag according to claim 1 or 2, wherein the half-cut line changes direction downwardly of the packaging bag, and then ends at a lower end where the left and right sides are inverted.

The invention described in claim 5 is as follows:
The packaging bag according to any one of claims 1 to 4, characterized in that the half-cut line is formed by irradiating with laser light.

The invention described in claim 6 is as follows:
The packaging bag according to any one of claims 1 to 5, wherein the left and right side edges of the packaging bag are provided with gussets formed by folding the laminate.

The invention described in claim 7 is as follows:
The packaging bag according to any one of claims 1 to 6, wherein the laminate constituting the packaging bag is provided with a gas barrier layer.

The invention described in claim 8 is as follows:
The packaging bag according to any one of claims 1 to 7, wherein a thermoplastic resin layer is provided on the outermost layer of the laminate.

The present invention provides a packaging bag at low cost that allows an opening for removing the contents to be easily formed using fingers.

The packaging bag of the present invention can be manufactured more productively by forming a pillow packaging bag shape with the joint seal portion as the bottom and seal portions at both the top and bottom ends.

In other words, this method allows pillow packaging bags to be produced continuously from a long length of film, which is advantageous in terms of cost and makes it possible to supply inexpensive packaging bags.

In addition, a half-cut line is provided on the top surface from the outside of the packaging bag, and the half-cut line is provided in a U-shape diagonally downward to the left and right, with its apex below the seal at the top end of the upper part of the packaging bag on the top surface and approximately equidistant from the left and right side ends. This makes it easier to open the packaging bag from the start of opening to the initial stage of opening, as it follows the half-cut line.

The half-cut line is a weak point, and opening the package is smooth with a moderate resistance. Once opened, it is difficult to reseal, which is expected to provide a tamper-proof effect.

In addition, the half-cut lines change direction downward before reaching the left and right side edges, and are set parallel to the side edges so that they reach the bottom of the upper surface of the packaging bag, making it easy to use your fingers to create an accurate opening along the half-cut lines.

In addition, because the half-cut line is continuous, it is possible to instantly form an opening and open the packaging bag in one motion.

In addition, the opening is located in the center of the top surface and has a large area that extends from top to bottom, making it very convenient to take out the contents.

In particular, according to the invention described in claim 2, the half-cut line has a V-shaped apex that is recessed, which has the effect of making it easier to form a slit that serves as a trigger for pinching with the fingers to form an opening.

In particular, according to the invention described in claim 3, the half-cut line changes direction downwards in the packaging bag and then continues laterally at its lower end, so that the laminate covering the opening can be cut off, separated, and removed, and the laminate at the opening does not get in the way of removing the contents, which is effective in improving convenience.

In particular, according to the invention described in claim 4, the half-cut line changes direction downwards on the packaging bag, and then ends at its lower end, where it is inverted on both the left and right sides, so it functions as a stopper to prevent tearing downwards, and can be used as the end point for opening. It is effective in determining the size and shape of the opening in advance, and it is possible to prevent unexpected tearing.

In particular, according to the invention described in claim 5, the half-cut line is formed by irradiating it with laser light, which allows for more excellent productivity and the formation of the half-cut line with greater precision.

In particular, according to the invention described in claim 6, the left and right side edges of the packaging bag are provided with gussets formed by folding the laminate, making the side edges expandable, which is effective in increasing the content volume of the packaging bag.

In particular, according to the invention described in claim 7, the laminate constituting the packaging bag is provided with a gas barrier layer, which is effective in improving the long-term preservation of the contents, making them unaffected by environmental conditions, and is therefore more suitable when the contents are food, and is also effective in preventing the leakage of volatile components of the contents.

In particular, according to the invention described in claim 8, a thermoplastic resin layer is provided on the outermost layer of the laminate, which makes it possible to heat seal the seam seal portion and the seal portions at both the upper and lower ends to the outer surface of the packaging bag and overlap them, which has advantages in terms of appearance, such as making the packaging bag more compact, and since the overlapped portions have increased rigidity, they serve as the framework of the packaging bag and are also effective in improving shape retention.

FIG. 1 is a schematic plan view (partially see-through) for explaining one embodiment of a packaging bag according to the present invention. FIG. 2 is a schematic plan view (partially see-through) illustrating another embodiment of the apex of the half-cut line in one embodiment of the packaging bag according to the present invention. FIG. 3 is a schematic perspective view for explaining a state of a packaging bag before being opened in one embodiment of the packaging bag according to the present invention. FIG. 4 is a schematic perspective view illustrating a state in which the packaging bag according to one embodiment of the present invention is opened. FIG. 5 is a schematic plan view (partially see-through) illustrating another embodiment of the half-cut line in one embodiment of the packaging bag according to the present invention. FIG. 6 is a schematic plan view (partially see-through) illustrating still another embodiment of the half-cut line in an embodiment of the packaging bag according to the present invention.

The present invention will be described in more detail below with reference to Figures 1 to 6. However, the present invention is not limited to the examples shown here. The present invention is defined by the claims.

Figure 1 is a schematic plan view (partially see-through) illustrating one embodiment of a packaging bag according to the present invention.

The present invention is a packaging bag made of a laminate with a plastic film as a base material and a sealant layer.

The packaging bag (100) is made by sealing the sealant layers facing each other, and in FIG. 1, a seam seal portion (1) is formed in the vertical direction. However, in FIG. 1, the side with the seam seal portion (1) is the bottom surface (10), which is the back surface of the packaging bag (100) and therefore is not visible, and part of the seam seal portion (1) is shown by a dashed line in the vertical direction in the center.

In the example shown in FIG. 1, the upper and lower ends are formed with an upper seal portion (2) and a lower seal portion (3) to produce a packaging bag (100), and the example shown in FIG. 1 is in the form of a pillow packaging bag. In this state, the innermost surface of the packaging bag (100) that comes into contact with the contents is a sealant layer.

On the other hand, the top surface (20) that is opposite the bottom surface (10) and faces the bottom surface (10) is shown as the front surface in FIG. 1, and this top surface (20) has a half-cut line (4) and a vertical half-cut line (5) on the outside of the packaging bag (100).

As shown by the dashed line in Figure 1, the half-cut line (4) has its apex (9) located below the upper seal portion (2) of the upper end portion (7) at the upper portion of the packaging bag (16) and equidistant from the left and right side ends (8).

That is, the half-cut lines (4) are formed from the apex (9) diagonally downward to the left and right, but before reaching the left and right side ends (8), they change direction downward of the packaging bag (100), become parallel to the side ends (8), become vertical half-cut lines (5), and reach the bottom of the packaging bag (17) to become the bottom end (6).

By providing the half-cut line (4) and the vertical half-cut line (5) in the shape shown in Figure 1, it is possible to form a large opening on the top surface (20) of the packaging bag (100). This is very convenient when removing the contents, especially when pinching or pulling them out with your fingers.

The packaging bag (100) can be opened by pinching part A and part B, which are close to the apex (9) of the half-cut line (4) in Figure 1, with the fingers, for example part A with the pad of the thumb and part B with the pad of the index finger, and pulling downward. This part acts as an opening trigger, and the bag can be opened along the half-cut line (4).

The half-cut line (4) and the vertical half-cut line (5) are scratched to a depth that does not penetrate all the way through the laminate that constitutes the packaging bag (100), and this portion becomes a mechanically weak part, making it possible to easily open the bag along the half-cut line (4) and the vertical half-cut line (5). In other words, the half-cut line (4) is a planned opening line, and is effective in forming an opening in the planned, precise shape.

The half-cut line acts as a mechanically weak point, so opening the package is smooth and provides a moderate amount of resistance. Once opened, the package is difficult to reseal, providing a tamper-proof effect.

The half-cut line (4) and the vertical half-cut line (5) can be formed, for example, by using a blade, or by irradiating with laser light. In particular, when formed by irradiating with laser light, the half-cut line (4) can be formed with higher productivity and precision.

The laser light may be, for example, a carbon dioxide laser. The half-cut line (4) and the vertical half-cut line (5) may be continuous lines or may be dashed lines.

Figure 2 is a schematic plan view (partially see-through) illustrating another embodiment of the apex of the half-cut line in one embodiment of the packaging bag according to the present invention.

In another embodiment of the apex (9) of the half-cut line (4) shown in FIG. 2, the half-cut line (4) is characterized in that the apex (9) of the U-shape is recessed to form a V-shape (11).

In the course of our intensive research into the present invention, we discovered that by forming a V-shape (11) at the apex (9) of the U-shape, this apex (9) is indented with the fingers to fold it in half, which serves as an opening for opening the bag, and then cutting along the half-cut line (4) provided as a mechanically weakened portion to form an opening in the top surface (20) of the packaging bag (100) is more effective in opening the bag.

As mentioned above, when the opening operation is performed by pinching part A and part B, which are close to the apex (9) of the half-cut line (4), with the fingers, for example part A with the pad of the thumb and part B with the pad of the index finger, and pulling downward, the V-shape (11) makes it easier to create an opening trigger.

Here, we will explain the material composition of the packaging bag (100) according to the present invention. As mentioned above, the present invention is a packaging bag (100) made of a laminate having a plastic film as a base material and a sealant layer.

The plastic film is a film made of a polymer resin composition, such as polyolefin (polyethylene, polypropylene, etc.), polyester (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyamide (nylon-6, nylon-66, etc.), polyimide, etc., and is selected appropriately depending on the application and contents of the packaging bag (100).

In particular, polypropylene and polyethylene terephthalate are more preferable in terms of film strength and cost when used as plastic films. In addition, when using oriented polyamide film, it is possible to impart toughness to the laminate against punctures and impacts.

The plastic film can also be laminated with other layers via an adhesive layer to form a laminate. The layer structure, material composition, thickness, etc. of the laminate can be designed appropriately according to the required quality of the packaging bag.

For example, in order to improve the long-term storage stability of the contents, an opaque layer that blocks ultraviolet light, such as a colored film, can be provided in the laminate that constitutes the packaging bag (100). Alternatively, a gas barrier layer can be provided in the laminate. For example, a gas barrier film can be used, which is made by providing a gas barrier layer on the surface of a plastic film.

Metal foils such as aluminum are also effective as gas barrier layers, but are unsuitable for cooking in a microwave oven because of the generation of high-frequency sparks. These can be selected appropriately depending on the application of the packaging bag (100).

In addition, when a gas barrier layer is provided, the processing of the half-cut line (4) and the vertical half-cut line (5) must be done in such a way that it does not damage or penetrate the gas barrier layer. If the gas barrier layer is damaged or penetrated, the gas barrier performance will inevitably be reduced.

In the case of gas barrier films, the plastic film used is a film made of a polymer resin composition, such as polyolefin (polyethylene, polypropylene, etc.), polyester (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyamide (nylon-6, nylon-66, etc.), polyimide, etc., and is selected appropriately depending on the application.

In particular, polypropylene and polyethylene terephthalate are more preferable in terms of film strength and price when used as the plastic film substrate.

In the case of gas barrier films, the gas barrier layer can be composed of a vapor deposition layer and a coating layer of an inorganic compound, and after providing an anchor coat on the plastic film, the vapor deposition layer and the coating layer are provided in that order.

For example, urethane acrylate can be used for the anchor coat layer of the gas barrier film. The anchor coat layer can be formed by using a coating method that applies a printing technique such as gravure coating with a paint in which a resin is dissolved in a solvent, or by using a commonly known coating method to form a coating film.

The deposition layer can be formed by coating an inorganic compound such as SiO or AlO onto a plastic film with an anchor coat layer using a vacuum deposition method, forming an inorganic compound layer by the vacuum deposition method. The thickness of the deposition layer should be 15 nm to 30 nm.

The coating layer can be formed by applying a coating agent based on a water-soluble polymer and an aqueous solution or a water/alcohol mixed aqueous solution containing at least one of (a) one or more alkoxides or their hydrolysates, or both, or (b) tin chloride, onto the film, and then heating and drying to form an inorganic compound layer by the coating method, which serves as the coating layer. In this case, a silane monomer can be added to the coating agent to improve adhesion with the anchor coat layer.

The inorganic compound layer has gas barrier properties even when it is only a coating film formed by the vacuum deposition method, but a gas barrier layer can also be formed by overlaying a coating layer, which is an inorganic compound layer formed by the coating method, on a deposition layer, which is an inorganic compound layer formed by the vacuum deposition method.

By combining these two layers, a reaction layer between the inorganic compound layer formed by the vacuum deposition method and the inorganic compound layer formed by the coating method is generated at the interface between the two layers, or the inorganic compound layer formed by the coating method fills and reinforces defects or micropores such as pinholes, cracks, and grain boundaries that occur in the inorganic compound layer formed by the vacuum deposition method, forming a dense structure.

As a result, it achieves high gas barrier properties, moisture resistance, and water resistance as a gas barrier film, and has the flexibility to withstand deformation caused by external forces, making it suitable for use as a packaging material.

In addition, when SiO, for example, is used as the gas barrier layer, the coating is transparent, so the contents can be seen from the outside of the packaging bag. These can be used appropriately depending on the application and required quality.

The sealant layer allows two laminates to be stacked with the sealant layers facing each other, and then bonded together by applying heat and pressure to heat seal, allowing the bags to be made into a packaging bag (100).

The packaging bag of the present invention can be manufactured more productively by forming a pillow packaging bag shape with the joint seal portion as the bottom and seal portions at both the top and bottom ends.

In other words, this method allows pillow packaging bags to be produced continuously from a long length of film, which is advantageous in terms of cost and makes it possible to supply inexpensive packaging bags.

The material for the sealant layer is generally a polyolefin-based thermoplastic resin, specifically low-density polyethylene resin (LDPE), medium-density polyethylene resin (MDPE), or linear low-density polyethylene resin (LLDPE).

In addition, ethylene-based resins such as ethylene-vinyl acetate copolymer (EVA), ethylene-α-olefin copolymer, and ethylene-methacrylic acid resin copolymer; blend resins of polyethylene and polybutene; and polypropylene-based resins such as homopolypropylene resin (PP), propylene-ethylene random copolymer, propylene-ethylene block copolymer, and propylene-α-olefin copolymer can be used.

To form the sealant layer, a film of molten resin can be formed using an extruder or the like to form a layer on the laminate. Alternatively, a sealant layer can be formed on the surface of the laminate by laminating a material that has already been formed into a film.

Figure 3 is a schematic perspective view of one embodiment of the packaging bag according to the present invention, illustrating the state of the packaging bag before it is opened.

The packaging bag (100) according to the present invention has a half-cut line (4) on the top surface (20), and the half-cut line (4) is provided from the outside of the packaging bag (100) with the apex (9) below the upper seal portion (2) and equidistant from the left and right side ends (8) at the top of the packaging bag (100).

The half-cut lines (4) are formed diagonally downward to the left and right, but before they reach the left and right side ends (8), they change direction downward on the packaging bag (100) and then become vertical half-cut lines (5) that run parallel to the side ends (8) before reaching the bottom end (6).

In the example shown in FIG. 3, gussets (12) are provided on the left and right side ends (8) of the packaging bag (100). The gussets (12) are folded flat between the bottom surface (10) and top surface (20) of the left and right side ends (8) before the contents are filled, and can expand to form the sides of the packaging bag (100) after the contents are filled.

The packaging bag (100) has gussets (12) at the left and right side ends (8), which allows the capacity of the packaging bag (100) to be increased.

Figure 4 is a schematic perspective view illustrating the appearance of a packaging bag opened in one embodiment of the present invention.

As mentioned above, the packaging bag (100) can be opened by pinching the area near the apex (9) of the half-cut line (4) shown in FIG. 2, for example by pinching part A with the pad of the thumb and part B with the pad of the index finger, and pulling in the direction of the arrow (13) to tear along the half-cut line (4) and the vertical half-cut line (5), forming an opening (14) on the top surface (20) of the packaging bag (100).

Opening the packaging bag (100), i.e., forming the opening (14), can be done easily and instantly with this one action, making it highly convenient.

As mentioned above, the half-cut line (4) is a scratch that does not penetrate the laminate that constitutes the packaging bag (100) completely, and therefore this part is mechanically weak, making it easy to open along the half-cut line (4) and the vertical half-cut line (5).

In other words, the half-cut line (4) and the vertical half-cut line (5) are intended opening lines, and an opening can be formed on the top surface (20) of the packaging bag (100) in the exact shape planned.

The half-cut line (4) and the vertical half-cut line (5) are mechanically weak points, so that the opening operation can be carried out smoothly with a moderate resistance. Also, once opened, it is difficult to reseal, making it tamper-proof.

As can be seen from the example shown in Figure 4, by forming the opening (14) in this shape, it is possible to form a large opening (14) on the top surface (20) of the packaging bag (100). This is extremely convenient when removing the contents, especially when pinching or pulling them out with fingers.

Figure 5 is a schematic plan view (partially see-through) illustrating another embodiment of the half-cut line in one embodiment of the packaging bag according to the present invention.

In the example shown in FIG. 5, the half-cut line (4) and the vertical half-cut line (5) continuing from it are connected in the left and right horizontal directions at their bottom ends (6). As a result, the half-cut line (4), the vertical half-cut line (5) continuing from it, and the horizontal half-cut line (15) continue to form a closed loop in an approximately pentagon.

That is, the laminate of the opening (14) formed by the half-cut lines (15) in the left and right horizontal directions at the lower end (6) can be cut off and separated and removed from the main body of the packaging bag (100). This has the effect of facilitating removal of the contents without the laminate of the opening (14) getting in the way.

Figure 6 is a schematic plan view (partially see-through) illustrating yet another embodiment of the half-cut line in one embodiment of the packaging bag according to the present invention.

In the example shown in Figure 6, the half-cut line (4) becomes a continuous vertical half-cut line (5), which changes direction downward in the packaging bag (100), and then ends at the lower end (6) where it is inverted on both the left and right sides.

At the bottom end (6), the left and right vertical half-cut lines (5) are inverted and end at this point, so the cutting along the vertical half-cut lines (5) stops here, and the shape of the opening (14) is determined.

In other words, the inverted portion can be the end point of the opening, and it is effective to determine the size and shape of the opening (14) in advance, thus enabling a stable and accurate opening operation.

In addition, the outermost layers of the laminate constituting the packaging bag (100) according to the present invention can be heat-sealed. In other words, a thermoplastic resin layer can be laminated on the outermost layer of the laminate.

Because the outermost layers of the laminate can be heat sealed, the joint seal portion (1) and the seal portions at both the top and bottom ends can be heat sealed to the outer surface of the packaging bag (100), which is advantageous in terms of appearance and also serves as a framework for the packaging bag (100), effectively increasing the rigidity of the entire packaging bag (100) and improving its shape retention.

If necessary, a printed layer can be provided on a layer of the laminate based on a plastic film that is visible from the outside of the packaging bag in order to improve the product's image, display necessary information about the contents, and improve the design. The printed layer may also be provided on the outermost layer of the packaging bag.

In addition, by printing along the half-cut line (4) and the vertical half-cut line (5) on the top surface (20) of the packaging bag, the half-cut line as the intended opening line can be made more clearly visible, and in this case, it can be used as a guideline for tearing during the opening process.

The printed layer may be provided on a part of the packaging bag (100), or may be provided over the entire surface of the packaging bag (100). Alternatively, a display unit may be provided without using a printed layer, for example by attaching a printed sticker to the surface of the packaging bag.

There are no particular restrictions on the printing method and printing ink, but any known printing method and printing ink may be appropriately selected, taking into consideration printability on plastic films, design such as color tone, adhesion, and, in the case where the contents are food, safety as a food container.

For example, a printing method can be selected from known printing methods such as gravure printing, offset printing, gravure offset printing, flexographic printing, silk screen printing, and inkjet printing. In general, gravure printing is preferred in terms of productivity, suitability for printing on plastic films, and high definition of the image.

In this way, the present invention makes it possible to provide a packaging bag at low cost, in which the opening for removing the contents can be easily formed using fingers, which is the objective of the present invention.

1: Joint seal portion 2: Upper seal portion 3: Lower seal portion 4: Half-cut line 5: Vertical half-cut line 6: Lower end 7: Upper end 8: Side end 9: Vertex 10: Bottom 11: V-shape 12: Gusset 13: Arrow 14: Opening 15: Left and right horizontal half-cut lines 16: Upper part of packaging bag 17: Lower part of packaging bag 20: Upper surface 100: Packaging bag

Claims (7)

A packaging bag made of a laminate having a plastic film as a base material and a sealant layer,
The packaging bag has a longitudinally extending seam portion formed therein,
The bag is made into a pillow packaging bag by forming seals at both top and bottom ends with the joint seal portion as the bottom.
A half-cut line is provided on the top surface opposite the bottom surface from the outside of the packaging bag,
The half-cut lines are provided in a U-shape at the top of the upper packaging bag, below the upper end seal and equidistant from the left and right side ends, and extend diagonally downward to the left and right.
Furthermore, the half-cut lines are provided so that before reaching the left and right side edges, they change direction downward and reach the lower part of the upper surface of the packaging bag in parallel with the side edges,
The packaging bag is characterized in that the half-cut line has a V-shape formed by concaving an apex of the V-shape . 2. The packaging bag according to claim 1 , wherein the half-cut line changes direction downwardly of the packaging bag and then continues laterally at its lower end. 2. The packaging bag according to claim 1 , wherein the half-cut line changes direction downwardly of the packaging bag, and then ends at a lower end where the left and right sides are inverted. The packaging bag according to any one of claims 1 to 3, characterized in that the half-cut line is formed by irradiating with laser light. The packaging bag according to any one of claims 1 to 4 , wherein the left and right side edges of the packaging bag are provided with gussets formed by folding the laminate. The packaging bag according to any one of claims 1 to 5 , wherein the laminate constituting the packaging bag is provided with a gas barrier layer. The packaging bag according to any one of claims 1 to 6 , wherein a thermoplastic resin layer is provided on an outermost layer of the laminate.

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