JP2022002983A - Bag container using non-stretchable pet film - Google Patents

Abstract

To provide a highly-transparent bag container comprising a desired film thickness and optimal stiffness (flexibility), namely a bag container giving a sense of high quality as compared with the conventional bag container, by easily performing bag-making processing such as heat sealing and folding.SOLUTION: A bag container 100 according to the present invention is formed from at least one sheet. The sheet includes a non-stretchable PET film layer in which at least one surface is exposed as either one of at least a base-material layer and an adhesion layer, and has a joined portion at which the non-stretchable PET film layers are joined together. In the bag container, the bag container is formed by folding and joining at least one sheet including the non-stretchable PET film layer. In the bag container, the non-stretchable PET film has appropriate stiffness (flexibility) and high transparency, so that it is possible to achieve functions of the bag container not achieved by other synthetic resin-material films, i.e., featuring functions such as high toughness, self-supporting, folding and use for advertisement.SELECTED DRAWING: Figure 1

Description

The present invention relates to a flexible packaging container using a sheet having at least a non-stretched PET film layer, that is, a bag container. Regarding bag containers to which etc. are applied.

As is well known in the past, there are bag containers using synthetic resin films such as polyethylene (PE) film, polypropylene (PP) film, and polyvinyl chloride (PVC). Such bag containers are used for various purposes by utilizing the characteristics of each film such as flexibility and transparency.

For example, a PE bag made of a PE film or a PP bag made of a PP film is generally called a plastic bag, which is an inexpensive and highly flexible bag (see, for example, Patent Document 1). Such PE bags or PP bags are used, for example, for food packaging bags, garbage bags, and the like. There are two types of PVC bags made from PVC film, soft and hard. Soft PVC bags are used as stretch films for wrapping food trays, and hard PVC bags are used for packaging miscellaneous goods and clothing. .. In the bag container using these synthetic resin films, the material is selected in consideration of transparency and flexibility according to the purpose of use.

By the way, the flexibility of a film mainly depends on the film thickness of the film, and if the materials are the same, naturally, the thinner the film, the more flexible it becomes. In other words, by making the film thicker, it is possible to form a highly rigid bag container. However, if the film is made thick, it becomes difficult to apply the conventional bag making process, the amount of material used increases, and the cost of bag making becomes high. Therefore, a bag container made of a film classified as a soft plastic such as a PP film or a PE film is highly flexible, but is not suitable for making a bag container that requires a certain degree of rigidity or higher.

On the other hand, there is a PET film as a transparent film having higher rigidity than a soft plastic film such as a PP film and a PE film, and some of them are used as a bag container. For such a PET film, stretched PET is used because of the film thickness control, particularly the ease of thinning.

However, due to its characteristics, the stretched PET has poor low-temperature heat welding property, and it is difficult to perform heat welding because it forms a bag container, and further, it is difficult to perform crease processing because the crystals are oriented. Therefore, it is not possible to manufacture a bag container with a stretched PET film alone, but by creating a multi-layer sheet in which other synthetic resin films with excellent workability are laminated, it is possible to perform heat welding and crease processing as a sheet. (See, for example, Patent Document 2 and Patent Document 3). That is, the stretched PET film cannot be heat-welded or crease-processed by itself, and is therefore unsuitable for producing a bag container.

By the way, as the PET film, in addition to the stretched PET film, there is a non-stretched PET film. Unlike the stretched PET film, the unstretched PET film can be heat-welded in a wide temperature range, and further, since the crystals are not oriented, crease processing is possible. However, it is difficult to control the film thickness of the conventional unstretched PET film, especially to make it thinner, and the film thickness cannot be reduced to a certain level or less. Therefore, even if the container is manufactured from the unstretched PET, the flexibility is insufficient and the box It had become a hard packaging container like a container. That is, it was unthinkable to manufacture a bag container from an unstretched PET film.

Japanese Unexamined Patent Publication No. 2014-118177 Japanese Unexamined Patent Publication No. 2001-55243 JP-A-2015-134491

As described above, some conventional synthetic resin films cannot easily achieve a certain level of rigidity, or some are difficult to process such as heat welding and creases, and are further formed to a desired film thickness. There was something I couldn't do. Therefore, it was not possible to manufacture a highly transparent bag container having the optimum rigidity (flexibility) with a desired film thickness.

The present invention has been made to solve the above-mentioned problems of bag making using a synthetic resin film, and can easily perform bag making such as heat welding and crease processing to obtain a desired film thickness. It is an object of the present invention to provide a highly transparent bag container having optimum rigidity (flexibility), that is, a bag container that gives a high-class feeling as compared with a conventional bag container.

The bag container according to the present invention is formed from at least one sheet. The sheet includes a non-stretched PET film layer as at least one of a base material layer and an adhesive layer, and has a joint portion to which the non-stretched PET film layers are bonded to each other.

In the bag container according to the present invention, at least one sheet containing the unstretched PET film layer is folded or joined to form a bag container. In this bag container, the non-stretched PET film has appropriate rigidity (flexibility) and high transparency, so that the bag container functions that could not be achieved by the film of other synthetic resin materials, that is, high toughness, self-supporting, folding It can achieve characteristic functions such as tatami mats and the use of advertisements.

In the bag container, the unstretched PET film may expose at least one surface, and the bonded portion may be bonded to the exposed surfaces of the unstretched PET film by heat welding. According to this bag container, the sheets are joined and made into a bag by heat welding such as a heat press method, a heat impulse method, and an ultrasonic heating method. Although heat welding was difficult with the stretched PET film, heat welding is possible at a low temperature for the unstretched PET film, which facilitates bag making. Further, the exposed surfaces of the non-stretched PET film layer are welded to each other, so that the bonded portion is firmly bonded.

The bag container includes a pair of facing front portions and a bottom surface portion that is continuous from the lower end of each front portion and connects the lower ends of the facing front portions, and the bottom surface portion includes the joint portion. According to this bag container, at least the bottom surface portion functions as a gusset portion, and the storage space of the bag container is greatly increased. Further, since the bottom surface portion contains a non-stretched PET film layer having high toughness, deformation and breakage of the bottom portion of the bag container that receives the most load of the contents are prevented.

The bag container is continuous from the side end of each front portion and includes a side surface portion connecting the side ends of the facing front portions, and the side surface portion has an inwardly foldable fold. According to this bag container, the side surface portion functions as a gusset portion, and the storage space of the bag container is greatly increased. On the other hand, when the bag container is not used, the bag container can be folded by folding the side surface portion inward along the crease.

In the conventional bag container using the stretched PET film, in order to provide a crease, it is necessary to have a multilayer of the stretched PET film and another film capable of crease processing. However, this bag container has a single layer. Even in the desired direction, it is possible to form creases and fold the sides inward in a V-shape without having to multi-layer with other crease-processable films. Can form extended creases.

The bag container may be formed from a single sheet, and the joint portion of the bottom surface portion may be joined by overlapping the sheet surfaces of the folded sheets. According to this bag container, unstretched PET films are joined to each other by heat welding on the bottom surface. In the bag container using the stretched PET film, it was necessary to laminate another film on the stretched PET film for heat welding processing, but this bag container is capable of heat welding between unstretched PET films. , Can be easily heat welded on the bottom surface. This makes it possible to manufacture a bottom gusset bag using an unstretched PET film. Further, since the bottom surface portion contains a non-stretched PET film layer having high toughness, deformation and breakage of the bottom portion of the bag container that receives the most load of the contents are prevented.

On the other hand, the front portion may have the joint portion extending from the upper end to the lower end. This bag container is a so-called gassho bag having a joint portion extending from the upper end to the lower end of the front portion. Since the sheet provided with the unstretched PET film layer is easier to perform heat welding and crease processing than the sheet provided with the stretched PET film layer, the gassho bag can be easily manufactured according to this bag body.

The joint portion of the bottom surface portion may be heat-welded by an ultrasonic heating method. Examples of the heat welding method include a heat pressing method, a fusing sealing method, and an ultrasonic heating method. In general, the hot press method makes it easy to control the welding temperature and the cost for welding is low. On the other hand, in the ultrasonic heating method, it is possible to pinpoint a portion or the like that is difficult to heat by the hot press method due to the shape of the non-heated material or the like.

The bag container may include a pair of facing front portions, and the front portions may have the joints at both ends. This bag container is a so-called flat bag, and has a joint portion in which the exposed surfaces of the unstretched PET film are joined to each other around the bag container, so that the bag can be easily manufactured.

The unstretched PET film layer may have a film thickness of 30 μm to 150 μm. By setting the unstretched PET film layer to a film thickness of 30 μm to 150 μm, a bag container having a desired rigidity can be manufactured. For example, by setting the non-stretched PET film layer to 30 μm to 150 μm, it has a certain degree of rigidity while having a desired toughness to the extent that it can be elastically deformed. As a result, the bag container 100 can ensure independence in a state where no contained material is contained, which was difficult to achieve with the conventional PP bag or PE bag.

The bag container according to the present invention is a bag container formed of at least one sheet, and the sheet includes a non-stretched PET film layer as a base material layer.

In the bag container according to the present invention, at least one sheet containing the unstretched PET film layer is folded or joined to form a bag container. In this bag container, the non-stretched PET film is used as the base material layer, and because it has appropriate rigidity (flexibility) and high transparency, the function of the bag container, which could not be achieved by the film of other synthetic resin materials, That is, it is possible to achieve characteristic functions such as high toughness, independence, folding, and use of advertisements.

The bag container may have an opening for taking in and out an container, and a closed structure may be formed by sealing the opening. The non-stretched PET film layer has excellent properties in oxygen permeability, water vapor permeability, and fragrance retention as compared with polyethylene film, polypropylene film and the like. Therefore, if the bag container is formed in a closed structure, even if the contained material is food or drink, the contained material can be kept for a long period of time without deteriorating the quality as compared with the polyethylene film, polypropylene film, or the like. Can be saved.

The bag container according to the present invention is a highly transparent bag container that can be easily heat-welded, crease-processed, etc., and has optimum rigidity (flexibility) with a desired film thickness, that is, a conventional bag container. It is possible to provide a bag container that gives a feeling of luxury as compared with a bag container.

It is a perspective view which shows the bag container (square bottom bag) which concerns on 1st Embodiment of this invention. It is a perspective view which shows the bag container shown in FIG. 1 from the bottom side. It is a development view which developed the bag container shown in FIG. It is a perspective view which shows the folded state of the bag container shown in FIG. It is a perspective view which shows the bag container (box pouch (registered trademark)) which concerns on 2nd Embodiment of this invention, (A) is the perspective view which shows the bag container from the top side, (B) is from the bottom side. be. It is a development view which developed the bag container shown in FIG. It is sectional drawing which shows the layer structure of the sheet of the bag container shown in FIG. It is sectional drawing which shows the layer structure which concerns on the modification of the sheet of the bag container shown in FIG. It is a perspective view which shows the bag container (stand bag) which concerns on 3rd Embodiment of this invention. It is a perspective view which shows the bag container (gassho bag) which concerns on 4th Embodiment of this invention. It is a perspective view which shows the bag container (two-way bag) which concerns on 5th Embodiment of this invention. It is a perspective view which shows the bag container (three-way bag) which concerns on the 6th Embodiment of this invention. It is a perspective view which shows the bag container (side seal bag) which concerns on 7th Embodiment of this invention.

The bag container 100 according to the first embodiment of the present invention will be described in detail with reference to FIGS. 1 to 4. The bag container 100 is a so-called square bottom bag provided with gussets (gusset portions) on the sides and the bottom. The square bottom bag forms a storage space for a substantially rectangular parallelepiped, and although it has a larger storage volume than other bags such as flat bags, it can be folded when it does not store the contents, that is, when it is not in use. It has characteristics. In addition, the square bottom bag has stable independence in use.

As shown in FIGS. 1 and 2, the bag container 100 is formed in a substantially rectangular parallelepiped, and has a pair of front portions 120 forming the front and back surfaces of the rectangular parallelepiped and a pair of side surface portions 140 forming both side portions of the rectangular parallelepiped. And a bottom surface portion 160 forming the bottom portion of the rectangular parallelepiped. As a result, the bag container 100 is formed with an opening that opens upward in FIG. The bag container 100 can take in and out the contents from the opening.

Each surface portion of the bag container 100 has a different aspect ratio, but is formed in a rectangular shape. However, each surface portion may have a trapezoidal shape or other shape as long as it functions as a bag container. As such a bag container, for example, a container having a rectangular front surface and a bottom surface and a trapezoidal side surface, a container having a rectangular bottom surface and a trapezoidal front surface and a side surface, and the like can be considered.

The bag container 100 is formed by bending one sheet shown in FIG. The seat has a first front seat portion 120a forming one front portion 120, a first side surface seat portion 140a forming one side surface portion 140, and a second front surface forming the other front portion 120. The sheet portion 120b, the second side surface sheet portion 140b forming the other side surface portion 140, and the joint sheet portion 180 are provided so as to be continuously arranged in order. The first and second front sheet portions 120a and 120b, the first and second side surface sheet portions 140a and 140b, and the joint sheet portion 180 are formed in a rectangular shape, although they have different aspect ratios. In the present specification, the rectangular or quadrangular term for specifying the shape of the sheet also includes a so-called corner R having a rounded corner portion.

Further, on the sheet, the first, second, third and fourth bottom sheet portions forming the bottom surface portion 160 continuously below each front surface portion 120 and each side surface portion 140 (lower side in FIG. 3). 160a, 160b, 160c, 160d are formed. Each of the bottom sheet portions 160a to 160d is formed in a substantially trapezoidal shape. As will be described later, the bottom sheet portions 160a to 160d are overlapped with each other to form the bottom surface portion 160. However, other shapes may be used as long as the bottom surface portion 160 can be formed. That is, the shape is not limited to a quadrangle such as a trapezoid, but may be a convex or concave shape.

Each front sheet portion 120a, 120b includes holes 122a, 122b cut out in an oval shape. The holes 122a and 122b are provided at opposite positions with the bag container 100 formed from the sheet. As a result, by passing a finger through the holes 122a and 122b, the holes 122a and 122b function as the handbag portion 122 (see FIGS. 1 and 2). However, the handbag may be achieved by other configurations. For example, it is also possible to make a handbag by making two desired holes in the bag container, passing both ends of one string through the holes, fixing each end with caulking or the like, and forming a ring with the string. ..

Each of the side surface sheet portions 140a and 140b has a first crease 142 extending in the vertical direction, and one obliquely downward portion and another obliquely downward portion extending from the middle of the lower portion of the first crease 142, respectively. It has two folds 144, and an inverted Y-shaped fold is formed by the first fold 142 and the second fold 144. Each fold is subjected to so-called ruled line processing, which is a kind of crease processing, and for example, a V-shaped groove is formed in a cross-sectional view of the sheet. This allows the sheet to be easily bent along the creases. The groove may be formed in a dotted line or a continuous line. However, the folds 142 and 144 may be bent without being processed into ruled lines.

The first fold 142 extends downward from the upper end in the longitudinal direction of each side sheet portion 140a, 140b and at the center position in the lateral direction of the side sheet portions 140a, 140b, and the second fold 144 extends. Extends from the middle of the first fold 142 to one lower end (left lower end) of the side sheet portions 140a and 140b and the other lower end (right lower end).

By bending the side sheet portions 140a and 140b along the first and second folds 142 and 144, the side surface portions 140 are formed in a V shape so as to be foldable inside the bag container, and are in an unused state. Sometimes the bag container 100 is foldable (see FIG. 4). As will be described later, the sheet is formed as a thin film sheet having an unstretched PET film as a base material layer, and can be crease-processed by the same method as that of a conventional plastic film. In the stretched PET film, the crystals were oriented by stretching, and crease processing could not be performed in the desired direction. However, in the non-stretched PET film, since the crystals are not oriented by stretching, crease processing can be performed in a desired direction.

By bending each face sheet portion at a right angle at the boundary line of each face sheet portion of the sheet, the sheet becomes a substantially rectangular parallelepiped bag container 100 as shown in FIGS. 1 and 2. The boundary line of each surface sheet portion may be formed by the same ruled line processing as the first and second folds 142 and 144.

An auxiliary sheet 100A having the same shape as the bottom surface portion 160 is placed in the bag container 100 in a state where the first to fourth bottom surface sheet portions 160a to 160d are overlapped with each other (see FIG. 1). With the auxiliary sheets 100A superposed on the first to fourth bottom sheet portions 160a to 160d, a plurality of portions of the bottom surface portion 160 are heat-welded by an ultrasonic method to form a plurality of first joint portions 162. (See Figure 2).

In the present embodiment, the bottom surface portion 160 is heat-welded by an ultrasonic method, but may be welded by a heat press method or a heat impulse method. However, in the bag making of square bottom bags, the bottom part is joined after forming the shape of the bag container, so it is necessary to insert a heater inside the bag container for heat welding processing of the hot press method and the heat impulse method. Yes, it is not suitable for heat welding.

Further, the bag container 100 includes a first front sheet portion 120a, while the front portion 120 includes a second joint portion 182. The second joint portion 182 is formed by superimposing the joint sheet portion 180 on a part of the side end of the first front sheet portion 120a and heat-welding the overlapped portion by a hot press method to join them. To. As a result, the unstretched PET film layers are bonded to each other. The hot press method is cheaper than other heat welding methods. Therefore, if there is no difficulty in processing, the hot press method is generally used for welding the plastic film. Although the first and second joint portions 162 and 182 are joined by heat welding, they may be joined by adhesion using an adhesive or the like. However, bonding by adhesive requires an adhesive, and the cost of bag making is high.

The sheet forming the bag container 100 has a single-layer structure consisting of only a non-stretched PET film layer. That is, both sides of the non-stretched PET film layer of the sheet are exposed. As a result, the unstretched PET film is a single layer and functions as a base material layer and an adhesive layer. Here, the base material layer means the layer having the highest rigidity among the plurality of layers of one sheet, and generally controls the rigidity and toughness of the sheet. Further, the adhesive layer means a layer in which one surface is joined to a surface of another sheet or the like. Therefore, the bag container 100 according to the present embodiment includes a non-stretched PET film layer in which the sheet functions as a base material layer or an adhesive layer, and has a joint portion in which the non-stretched PET film layers are bonded to each other.

The bag container 100 is used in the shape of a substantially rectangular parallelepiped shown in FIG. 1 in a used state, that is, when accommodating an contained object. On the other hand, when not in use, that is, when the contained material is not stored, the side surface portion is folded inward in a V shape and folded into the sheet shape shown in FIG.

Each front portion 120 is formed in a quadrangle having the same shape, and the sides face each other so as to correspond to each other. That is, the lower ends of the quadrangle of the front portion 120 correspond to each other, and the bottom surface portion 160 is formed so as to connect the lower ends. Further, the side ends of the quadrangle of the front surface portion 120 correspond to each other, and each side surface portion 140 is formed so as to connect these two side ends.

In the present embodiment, the unstretched PET film layer has a film thickness of 80 μm. The unstretched PET film having a film thickness of 80 μm has a certain degree of rigidity while having a desired toughness to the extent that it can be elastically deformed. As a result, the bag container 100 secures independence in a state where no contained material is contained, which was difficult to achieve with the conventional PP bag or PE bag.

However, the unstretched PET film layer may have a film thickness of 30 μm to 150 μm. If the thickness is within that range, the toughness is maintained to the extent that it can be elastically deformed, and the flexibility is such that it does not become a box container. Further, the non-stretched PET film layer may have a film thickness of 80 μm to 120 μm. If the thickness is within that range, the toughness is maintained to the extent that it is self-supporting, and it has the flexibility to be appropriately deformed according to the contents. The relationship between these film thickness and toughness depends on the thickness of other film layers when a synthetic resin film is laminated in addition to the unstretched PET film layer, but when the unstretched PET layer forms a substrate layer, , The generally unstretched PET layer dominates the toughness.

The bag container 100 according to the embodiment of the present invention is formed of one sheet in which the unstretched PET film layer functions as a base material layer and an adhesive layer. The unstretched PET film has high transparency, gloss, and toughness (so-called stiffness), and the bag container made of a sheet having the unstretched PET film as a base material is compared with the conventional sheet made of synthetic resin. Arouse a sense of luxury.

The bag container 100 according to the present embodiment is formed by cutting a sheet cut into a quadrangle of a predetermined size, a so-called cut sheet, into a predetermined shape. However, the sheet may be formed by cutting out a long sheet wound in a roll shape, that is, a so-called roll sheet.

Next, the bag container 200 according to another embodiment of the present invention will be described with reference to FIGS. 5 to 7. The bag container 200 is a box pouch (registered trademark) which is a form of a square bottom bag. Similar to the bag container 100, the bag container 200 is provided with a gusset (gusset portion) on the side portion and the bottom portion. However, the bag container 200 is formed by a manufacturing method different from that of the bag container 100.

The box pouch can be formed, for example, by cutting, bending and heat welding two roll sheets. The front part of the box pouch may be formed in another shape. For example, by forming the front part in the shape of the character and joining the periphery of the front part, the impression that the character stands upright. Can form a bag container that evokes.

As shown in FIGS. 5 and 6, the bag container 200 is formed in a substantially rectangular parallelepiped like the bag container 100, and has a pair of substantially quadrangular front portions 220, a pair of substantially quadrangular side surface portions 240, and a substantially quadrangular bottom surface. A unit 260 is provided. However, the bag container 200 is formed of a plurality of sheets, whereas the bag container 100 is formed of one sheet. Further, the bag container 200 has a joint portion 280 for joining the front surface portion 220 and the side surface portion 240, a joint portion 282 for joining the front surface portion 220 and the bottom surface portion 260, and a joint portion for joining the side surface portion 240 and the bottom surface portion 260. A unit 284 is provided.

The joint portion 280 is formed at both side ends of the front surface portion 220 and both side ends of the side surface portion 240. Further, the joint portion 282 is provided at the lower end of the front portion 220 and the front and rear ends of the bottom surface portion 260. Further, the joint portion 284 is provided at the lower end of the side surface portion 240 and the left and right ends of the bottom surface portion 260.

Unlike the sheet of the bag container 100, the sheet 200S of each surface portion constituting the bag container 200 has a two-layer structure in which the stretched PET film layer 200b is laminated on the non-stretched PET film layer 200a as shown in FIG. ing. The stretched PET film layer functions as a decorative layer, and the non-stretched PET film layer functions as a base material layer and an adhesive layer. Here, the decorative layer means a layer for decorating a sheet by forming decorative portions such as characters, figures, and patterns and laminating them on another layer.

The stretched PET film is produced by a conventionally well-known molding method by uniaxial stretching or biaxial stretching. On the other hand, the non-stretched PET film is produced by a film forming method using a conventionally well-known roll device. (For example, see JP-A No. 11-235747). That is, in the present specification, the stretched PET film is intentionally stretched and the crystal orientation is aligned, and the unstretched PET is not intentionally stretched.

The stretched PET film layer 200b has a partial opaque portion (for example, the portion of “ABC” in FIG. 5) 202 and is a decorative layer. That is, in the sheet 200S, the stretched PET film layer 200b having the opaque portion 202 is laminated on the transparent non-stretched PET film layer 200a, and the opaque portion has a display function of displaying characters, figures, patterns and the like.

The opaque portion 202 was printed with desired characters, figures, patterns, etc. on the stretched PET film, and the printed stretched PET film was laminated on the non-stretched PET film, so that the desired characters, figures, patterns, etc. were displayed. The sheet is manufactured. The unstretched PET film 200a and the stretched PET film 200b are laminated by a conventionally well-known laminating device.

In the bag container 200, the unstretched PET film layer is exposed on the surface of each surface located inside the bag. Therefore, the exposed surfaces of the unstretched PET film layer are directly bonded to each other in the bonded portions 280, 282, and 284. Here, the non-stretched PET film layer and the stretched PET film layer or another synthetic resin film layer may be difficult to perform heat welding due to the difference in melting temperature and the action of intermolecular bonding. Therefore, the exposed surfaces of the non-stretched PET film layer are directly bonded to each other, so that the bonded portion is firmly bonded.

Since each joint portion of the bag container 200 is formed around each surface portion, heat welding is performed from the outside of the bag container 200 by a hot press method. As an apparatus capable of making such a bag container, for example, there is a bag making machine described in Japanese Patent Application Laid-Open No. 2011-67997. However, each joint may be heat welded by another method.

By joining the bag container 200 in this way, the pair of front portions 220 of the bag container 200 face each other, the bottom surface portion 260 is continuous from the lower ends of both front portions 220, and the lower ends of both front portions 220 are connected. , The side surface portion 240 is formed so as to be continuous from the side ends of both front surface portions 220 and to connect the side ends of both front surface portions 220.

The side surface portion 240 of the bag container 200 branches from the middle of the first fold 242 extending in the vertical direction and the first fold 242, similarly to the side surface portion 140 of the bag container 100 according to the first embodiment. The first fold 242 and the second fold 244 form an inverted Y-shaped fold so as to have a second fold 244 extending diagonally downward and the other diagonally downward. There is. Further, the bottom surface portion 260 has a third fold 246. Each fold is so-called ruled line processing. However, the folds 242, 244 and 246 may be bent without being ruled.

This allows the sheet to be easily bent along the creases. The side surface portion 240 is bent along the first to third folds 242, 244 and 246 so that the side surface portion 240 and the bottom surface portion 260 can be folded into the inside of the bag container in a V shape. The bag container 200 can be folded when not in use.

The sheet 200S has a two-layer structure in which a stretched PET film layer is laminated on a non-stretched PET film layer, but may have a single-layer structure consisting of only a non-stretched PET film layer, or may be a non-stretched PET film layer. As long as one surface is exposed, another layer structure having a multi-layer structure may be used.

Further, in the bag container 200, the unstretched PET film functions as a base material layer and an adhesive layer, but may function as at least one of the base material layer and the adhesive layer. That is, either one of the base material layer and the adhesive layer may be formed from the non-stretched PET film layer, and the other one may be formed from the other synthetic resin film layer or the stretched PET film layer.

The bag container 200 is all formed of sheets having the same layer structure, but each sheet may have a different layer structure. For example, the front surface portion 220 is formed from a sheet having a two-layer structure of an unstretched PET film layer and a stretched PET film layer, and the side surface portion 240 and the bottom surface portion 260 are formed from a single-layer structure sheet containing only the unstretched PET film layer. You may do it.

As a modification of the sheet 200S of the bag container 200, for example, there is the sheet 200T shown in FIG. The sheet 200T has a three-layer structure, whereas the sheet 200S has a two-layer structure. The sheet 200T includes a PE film layer 200c that functions as a base material layer, a non-stretched PET film layer 200d that functions as an adhesive layer, and a stretched PET film layer 200e that functions as a decorative layer.

Even with such a sheet 200T, since one surface of the unstretched PET film layer 200d is exposed, if the bag is made so that the surface is arranged inside the bag container 200, the unstretched PET film layer is formed. You can join them together.

Next, the bag containers 300, 400, 500, 600, 700 will be described with reference to FIGS. 9 to 13. These bag containers can be made by a conventionally well-known bag making method.

The bag container 300 shown in FIG. 9 is referred to as a stand bag, and includes a pair of substantially quadrangular front portions 320 and a substantially circular bottom portion 360. The bag container 300 is formed of a plurality of sheets. For example, a stand bag can be formed by bending, cutting, heat welding, etc., two roll-shaped sheets. The front portion of the stand bag may be formed in another shape. For example, by forming the front portion in the shape of the character and joining the periphery of the front portion, the impression that the character stands upright. Can form a bag container that evokes.

Similar to the sheet 200S, the sheet forming the front portion 320 has a two-layer structure composed of a non-stretched PET film layer and a stretched PET film layer. Further, the non-stretched PET film layer functions as a base material layer and an adhesive layer, and the stretched PET film layer functions as a decorative layer. As a result, the front portion 320 of the bag container 300 is displayed with the “ABC” character as the opaque portion 302, similarly to the bag container 200.

Each sheet forming the bag container 300 may have another layer structure as long as at least one surface of the unstretched PET film layer is exposed. Therefore, for example, the front surface portion 320 is formed from a sheet having a two-layer structure of an unstretched PET film layer and a stretched PET film layer, and the bottom surface portion 360 is formed from a single-layer structure sheet containing only an unstretched PET film layer. May be good. Further, when each sheet forming the bag container 300 has two or more layers, the non-stretched PET film layer may function as at least a base material layer or an adhesive layer.

Each surface of the bag container 300 is joined by heat welding. That is, the front portion 320 includes a joint portion 380 in which both sides are joined to each other by heat welding, and the front portion 320 and the bottom portion 360 are joined by heat welding in which their peripheral edges are overlapped with each other. It is equipped with 382. In the joint portion 380, the exposed surfaces of the unstretched PET film layer are directly bonded to each other. Since each joint portion of the bag container 300 is formed around each surface portion, heat welding is performed from the outside of the bag container 300 by a hot press method. However, each joint may be heat welded by another method.

By joining the bag container 300 in this way, the pair of front portions 320 of the bag container 300 face each other, and the bottom surface portion 360 is continuous from the lower ends of both front portions 320 and connects the lower ends of both front portions 320. Is formed like this.

A crease 362 extending in one direction is formed on the bottom surface 360 portion of the bag container 300. The crease 362 is so-called ruled line processing, and for example, a V-shaped groove is formed in the thickness direction of the sheet. This allows the sheet to be easily bent along the creases. By bending the bottom surface along the fold 362, the bag container 300 is formed so as to be foldable inside the bag container in a V shape, and the bag container 300 can be folded when not in use. However, the fold 362 may be bent without being processed into a ruled line.

In the present embodiment, the bag container 300, which is a stand bag, includes a front portion 320 formed in a quadrangle shape, but the front portion may be formed in another shape. For example, by forming a front portion in the shape of a character and joining the periphery of the front portion, it is possible to form a bag container that evokes the impression that the character is upright.

The bag container 400 shown in FIG. 10 is referred to as a gassho bag and includes a pair of substantially square front portions 420. The bag container 400 is a so-called flat bag, but may be formed as a gusset bag provided with a gusset portion. The bag container 400 is made of one sheet. That is, one quadrangular sheet is bent at a position of approximately 1/4 on both the left and right sides, and both ends of the sheet are overlapped and joined.

The sheet forming the bag container 400 has a single-layer structure consisting of only a non-stretched PET film layer. However, as long as at least one surface of the unstretched PET film layer is exposed, another layer structure may be used. Therefore, for example, the bag container 400 may be formed from a sheet having a two-layer structure of a non-stretched PET film layer and a stretched PET film layer. Further, when each sheet forming the bag container 400 has two or more layers, the non-stretched PET film layer may function as at least a base material layer or an adhesive layer. For example, if the sheet of the bag container 400 has a two-layer structure in which the non-stretched PET film layer is used as the base material layer and the adhesive layer and the stretched PET film layer is used as the decorative layer, as in the sheet 200S, the bag container 200 is used. Similarly, characters, figures, patterns, etc. can be displayed as opaque portions.

The bag container 400 includes a joint portion 480 extending from the upper end to the lower end in the center of one front portion 420 in the left-right direction and a joint portion 482 extending in the left-right direction at the bottom portion. That is, one front portion 420 includes a joint portion 480 in which both ends of the above-mentioned one quadrangular sheet are overlapped and joined by heat welding, and both front portions 420 are heat-welded to the bottom thereof. It is provided with a joint portion 482 joined by. In the bonded portions 480 and 482, the exposed surfaces of the unstretched PET film layer are directly bonded to each other. Each joint portion of the bag container 400 is heat-welded from the outside of the bag container 400 by a hot press method. However, each joint may be heat welded by another method.

In the bag container 400, the joint portion 480 is provided in the substantially center of the front portion 420 by bending the above-mentioned one quadrangular sheet at two positions of the left and right 1/4, but by changing the bending position, the joint portion 480 is provided. The joint portion 480 can be provided at a desired position.

In the present embodiment, the bag container 400, which is a gassho bag, includes a front portion 420 formed in a quadrangle shape, but the front portion may be formed in another shape. For example, by forming a front portion in the shape of a character, a bag container having that character shape can be formed.

The bag container 500 shown in FIG. 11 is referred to as a two-way bag and includes a pair of substantially square front portions 520. The bag container 500 is made of one sheet. That is, both front portions 520 of the bag container 500 are formed by bending one rectangular sheet at the center and superimposing the sheets. The folds of the bag container 500 may function as the bottom of the bag container, and the folds may be formed by the same ruled line processing as the first and second folds 142 and 144.

The sheet forming the front portion 520 has a single-layer structure consisting of only a non-stretched PET film layer. However, as long as at least one surface of the unstretched PET film layer is exposed, another layer structure may be used. Therefore, for example, the bag container 500 may be formed from a sheet having a two-layer structure of a non-stretched PET film layer and a stretched PET film layer. Further, when each sheet forming the bag container 500 has two or more layers, the non-stretched PET film layer may function as at least one of a base material layer and an adhesive layer. For example, if the sheet of the bag container 500 has a two-layer structure in which the non-stretched PET film layer is used as the base material layer and the stretched PET film layer is used as the decorative layer as in the sheet 200S, the same as in the bag container 200. Characters, figures, patterns, etc. can be displayed as opaque parts.

Further, the bag container 500 has a joint portion 580 in which both sides of the overlapped front portions 520 are joined to each other by heat welding. In the joint portion 580, the exposed surfaces of the unstretched PET film layers are directly bonded to each other. Since each joint portion 580 of the bag container 500 is formed around each surface portion, heat welding is performed from the outside of the bag container 500 by a hot press method. However, each joint portion 580 may be heat-welded by another method.

In the present embodiment, the bag container 500, which is a two-sided bag, includes a pair of substantially quadrangular front portions 520, but the front portions may be formed in another shape. For example, by forming a pair of front parts in the shape of a character, folding back a common side of both front parts, and joining the other periphery of the front part except for a part that becomes an opening, the character shape is formed. A bag container can be formed.

The bag container 600 shown in FIG. 12 is referred to as a three-way bag and includes a pair of substantially square front portions 620. The bag container 600 is formed of two sheets having the same shape.

Each sheet forming the bag container 600 has a single-layer structure consisting of only a non-stretched PET film layer. However, as long as at least one surface of the unstretched PET film layer is exposed, another layer structure may be used. Therefore, for example, one front portion 620 is formed from a sheet having a two-layer structure of an unstretched PET film layer and a stretched PET film layer, and the other front portion 620 is formed from a single-layer structure sheet containing only an unstretched PET film layer. You may try to do it.

Further, when each sheet forming the bag container 600 has two or more layers, the non-stretched PET film layer may function as at least one of a base material layer and an adhesive layer. For example, if the sheet of the bag container 600 has a two-layer structure in which the non-stretched PET film layer is used as the base material layer and the stretched PET film layer is used as the decorative layer as in the sheet 200S, the same as in the bag container 200. Characters, figures, patterns, etc. can be displayed as opaque parts.

The bag container 600 has joints 680,682 in which both sides and bottoms of the overlapped front portions 620 are joined to each other by heat welding. In the bonded portions 680 and 682, the exposed surfaces of the unstretched PET film layer are directly bonded to each other. Since each of the joint portions 680 and 682 of the bag container 600 is formed around the front portion 620, heat welding is performed from the outside of the bag container 600 by a hot press method. However, each joint may be heat welded by another method.

In the present embodiment, the bag container 600, which is a three-sided bag, includes a pair of substantially quadrangular front portions 620, but the front portions may be formed in another shape. For example, by forming a pair of front parts in the shape of a character and joining the periphery of the front parts in a state where both front parts are overlapped with each other except for a part that becomes an opening, a bag container having that character shape is formed. can.

The bag container 700 shown in FIG. 13 is referred to as a side seal bag and includes a pair of substantially square front portions 720. The bag container 700 is made of one sheet. That is, both front portions 720 of the bag container 700 are formed by bending one rectangular sheet at the center and superimposing the sheets. This crease may be lined.

Further, the bag container 700 has a joint portion 780 in which the side sides of the overlapped front portions 720 are joined to each other by heat welding. In the bonded portion 780, the non-stretched PET film layers are directly bonded to each other. Each joint portion 780 of the bag container 700 is heat-welded from the outside of the bag container 700 by a heat welding method. According to the heat fusing method, the sheet can be cut at the same time as heat welding, so that a desired joint can be easily formed.

The sheet forming the bag container 700 has a single-layer structure consisting of only a non-stretched PET film layer. However, as long as at least one surface of the unstretched PET film layer is exposed, another layer structure may be used. Therefore, for example, the bag container 700 may be formed from a sheet having a two-layer structure of a non-stretched PET film layer and a stretched PET film layer.

Further, when each sheet forming the bag container 700 has two or more layers, the non-stretched PET film layer may function as at least a base material layer or an adhesive layer. For example, if the sheet of the bag container 700 has a two-layer structure in which the non-stretched PET film layer is used as the base material layer and the adhesive layer and the stretched PET film layer is used as the decorative layer, as in the sheet 200S, the bag container 200 is used. Similarly, characters, figures, patterns, etc. can be displayed as opaque portions.

In the present embodiment, the bag container 700, which is a side seal, includes a pair of substantially quadrangular front portions 720, but the front portions may be formed in another shape. For example, by forming a pair of front parts in the shape of a character and joining the periphery of the front parts in a state where both front parts are overlapped with each other except for a part that becomes an opening, a bag container having that character shape is formed. can.

Further, in the bag container according to the present embodiment, the opening for taking in and out the contents may be sealed by a chuck or heat welding. As a result, the bag container is formed into a closed structure. Here, the unstretched PET film layer used for the bag container according to the embodiment of the present invention is superior in oxygen permeability, water vapor permeability, and fragrance retention as compared with conventional polyethylene films, polypropylene films, and the like. It has other characteristics.

Therefore, when the bag container according to the present embodiment is formed in a closed structure, the quality is not deteriorated as compared with the polyethylene film, polypropylene film, etc., even when the contained food or the like is food or drink. , The contents can be stored for a long time.

The bag container according to the embodiment of the present invention may be manually produced without using a bag making machine. One of the features of the bag container according to the embodiment of the present invention is that the unstretched PET film layer is used for at least one of the base material layer and the adhesive layer. This makes it possible to provide a bag container utilizing the physical characteristics of the unstretched PET film.

The embodiment of the present invention has been described above. However, the present invention is not limited to these descriptions. The above-mentioned embodiments which have been appropriately designed by those skilled in the art are also included in the scope of the present invention as long as they have the features of the present invention.

The present invention can be used for bag making of a bag container made of synthetic resin.

100,200,300,400,500,600,700 Bag container 200S Sheet 200a Unstretched PET film layer 200b Stretched PET film layer 120, 220, 320, 420, 520, 620, 720 Front part 140, 240, Side part 142 , 144,242,244,246,342,442,562,762 Folds 160,260,360 Bottom part 162,182,280,282,284,380,382,480,482,580,680,682,780 Joint

Claims (11)

A bag container made of at least one sheet.
The sheet contains a non-stretched PET film layer as at least one of a base material layer and an adhesive layer, and has a joint portion to which the non-stretched PET film layers are bonded to each other.
The bag container according to claim 1, wherein the unstretched PET film layer exposes at least one surface, and the joint portion joins the exposed surfaces of the unstretched PET film by heat welding.
A pair of facing front parts and
It is provided with a bottom portion that is continuous from the lower end of each front portion and connects the lower ends of the facing front portions.
The bag container according to claim 2, wherein the bottom surface portion includes the joint portion.
It is provided with a side surface portion that is continuous from the side end of each front portion and connects the side ends of the facing front portions.
The bag container according to claim 3, wherein the side surface portion has a fold that can be folded inward.
Formed from a single sheet,
The bag container according to claim 3 or 4, wherein the joint portion of the bottom surface portion is joined by superimposing the bent sheets.
The bag container according to any one of claims 2 to 5, wherein the front portion has the joint portion extending from the upper end to the lower end.
The bag container according to any one of claims 3 to 5, wherein the joint portion of the bottom surface portion is heat-welded by an ultrasonic heating method.
With a pair of facing front parts
The bag container according to claim 2, wherein the front portion has the joint portions at both ends.
The bag container according to any one of claims 1 to 8, wherein the unstretched PET film layer has a film thickness of 30 μm to 150 μm.
A bag container made of at least one sheet.
The sheet is a bag container containing a non-stretched PET film layer as at least one of a base material layer and an adhesive layer.
It has an opening to put in and take out the contents,
The bag container according to any one of claims 1 to 10, wherein a closed structure is formed by sealing the opening.

Images