Packaging

Abstract

The present invention provides a packaging material that allows for the acquisition of images suitable for individual identification, even when the contents are filled. [Solution] In a package in which contents are filled into a flexible packaging container formed by heat-sealing a laminate 1, the laminate has a resin base material 10, a printed layer 20 formed on the base material, and a heat-seal layer 30 that covers at least a part of the printed layer. The resolution of the printed layer 20 is 100 or less as LPI, and the index calculated based on a predetermined formula is less than 1.4.

Description

Technical Field

[0001] The present invention relates to a package, and more particularly to a package in which a packaging container formed of a flexible packaging material is filled with contents.

Background Art

[0002] A packaging container formed of a flexible plastic film, also referred to as a pouch, is widely used as a container for toiletries, foods, etc. as described in Patent Document 1. In many such packaging bags, barcodes such as JAN codes are printed on the surface for purposes such as logistics management.

[0003] Barcodes, characters, designs, etc. printed on articles are slightly different from one another in detail, even though their appearances are generally the same, and there are no completely identical ones. Focusing on this point, a technique called artifact metrics for identifying an article based on a database that stores feature points included in an image obtained by imaging an identifier using a barcode, character, design, etc. as the identifier has been studied. Artifact metrics is expected to be applied to authenticity determination of articles, traceability, sales promotion campaigns linked to article purchases, etc.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In artifact metrics, a database is indispensable. As the timing of creating the database, there are roughly two patterns: one is that the manufacturer creates it before shipment, and the other is that it is created after shipment. In the latter case in particular, whether the image is taken by the seller or the buyer, the image will be of the packaging with its contents filled. However, the outer surface of a package filled with contents is often not flat, making it more difficult to maintain consistent image quality compared to when imaging a flat packaging bag. Therefore, the accuracy of individual identification may not be stable.

[0006] In view of the above circumstances, the present invention aims to provide a packaging that can acquire images that allow for suitable individual identification even when the contents are filled. [Means for solving the problem]

[0007] The present invention relates to a package in which contents are filled into a flexible packaging container formed by heat-sealing a laminate. The laminate comprises a resin substrate, a printed layer formed on the substrate, and a heat-seal layer covering at least a portion of the printed layer. The resolution of the printed layer is 100 or less as LPI, and the index calculated based on the following formula is less than 1.4. (Formula) ... Index = Volume of contents (mL) / (Dimensions of the packaging container in the left-right direction excluding the heat-sealed area (mm) × 2 + Dimensions of the packaging container in the up-down direction excluding the heat-sealed area (mm)) [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a packaging that can acquire images that allow for suitable individual identification even when the contents are filled. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view showing the layer structure of a laminate according to one embodiment of the present invention. [Figure 2] This figure shows a standing pouch formed using the same laminate. [Figure 3] This is a diagram showing the standing pouch disassembled. [Modes for carrying out the invention]

[0010] The following describes one embodiment of the present invention with reference to Figures 1 to 3. First, the laminate constituting the packaging bag according to this embodiment will be described. Figure 1 is a schematic cross-sectional view showing the layer structure of the laminate 1 according to this embodiment. As shown in Figure 1, the laminate 1 comprises a base material 10, a printed layer 20 formed on the base material 10, and a heat-seal layer 30 formed on the printed layer 20.

[0011] The base material 10 is formed in the form of a film or sheet using a resin material. The base material 10 shown in Figure 1 is a single layer, but it may have multiple layers. Examples of resin materials constituting the base material 10 include polyethylene terephthalate (PET), stretched polypropylene (OPP), and stretched polyamide (Ony).

[0012] A gas barrier layer may be provided on the base material 10 for purposes such as extending the shelf life of the contents. The gas barrier layer can block oxygen, water vapor, etc. The gas barrier layer can be a vapor-deposited film of a metal such as aluminum, or a metal oxide such as silica or alumina, but metal foil is not used. This point will be discussed later.

[0013] The printed layer 20 is formed on the first surface 10a of the substrate 10 and constitutes an identifier used for artifact metrics. In one example, the identifier is a code, a character, or a graphic. The code can be a one-dimensional code or a two-dimensional code. Examples of one-dimensional codes include JAN codes, while examples of two-dimensional codes include QR codes (registered trademark) and data matrices.

[0014] The heat-seal layer 30 is bonded to the substrate 10 so as to generally cover the first surface 10a side of the substrate 10, which includes the printed layer 20. The heat-seal layer 30 can be formed using a film made of various polyethylenes such as low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE), or unoriented polypropylene (CPP), or using a heat-seal varnish.

[0015] The laminate according to this embodiment may include an intermediate layer between the base material 10 and the heat-sealing layer 30. In this case, the above-described printing layer 20, gas barrier layer, etc. may be provided in the intermediate layer.

[0016] FIG. 2 shows a standing pouch 51 which is an example of the packaging container according to this embodiment. As shown in an exploded view in FIG. 3, the standing pouch 51 is formed of two laminates 1 constituting the front and rear surfaces and a bottom film 2 disposed therebetween, and its basic structure is known. The standing pouch 51 can be formed by heat-sealing three sides while sandwiching the bottom film 2 between two laminates 1. After the interior is filled with the contents through the unsealed opening Op and then the opening Op is sealed, a package using the standing pouch 51 is completed.

[0017] The packaging container according to this embodiment is not limited to the standing pouch 51, and there is no particular limitation on its shape and structure. Some examples of other cases are as follows, and other aspects may also be possible. · A side gusset pouch formed by sandwiching a folding film similar to the bottom film 2 on the side · A non-self-standing pouch made using only two laminates 1 · A pouch formed by folding back a single laminate 1 and joining it by heat-sealing · A pouch having a tubular or half-pipe-shaped member (including a spout) attached to the pouring outlet

[0018] In the completed packaging container, the base material 10 constitutes the outer surface, and the printing layer 20 is present at a predetermined position. The printing layer 20 can be visually recognized through the transparent base material 10. Since the printing layer may be provided on at least one of the front and rear surfaces, for example, in the case of the standing pouch 51, a structure excluding the printing layer 20 from the laminate 1 may be used for one of the front and rear surfaces.

[0019] The identifiers formed on multiple packaging containers by the printed layer 20 have the same basic appearance, but possess subtle differences that are not easily recognizable by the human eye or code readers such as scanners. Examples include edge linearity at the edges, contrast between light and dark areas, differences in patterns (extra dark areas), partial blurring or defects in printing, fine patterns due to the printing method, aspect ratio of the outer shape, and inconsistencies in placement and pattern size. Artifact metrics use these differences as feature points for individual identification, enabling individual identification of packaging containers and packaging bodies.

[0020] Incidentally, since the packaging container according to this embodiment is formed using a flexible laminate 1, when contents are filled, the laminate 1 deforms according to the amount and shape of the contents, regardless of the manner in which the contents are filled. Depending on how the laminate 1 deforms, the part on which the printed layer 20 is formed may bend, and in this case, the appearance of the printed layer 20 changes, which may cause the characteristic points in the image of the captured printed layer 20 to be lost or changed.

[0021] This could affect the accuracy of artifact metric identification, whether the matching database is created before or after shipment. Firstly, if the database is created after shipment, there is a possibility that the database itself may not be properly constructed due to reasons such as the reference images stored in the database not adequately retaining feature points, which could lead to poor identification. On the other hand, if a database is created before shipment, it is possible to build an appropriate database by imaging the packaging container in its flat state before filling. However, if the feature points are not properly captured in the matching images taken by the purchaser or others, the identification accuracy may still decrease.

[0022] The inventors focused on this point and investigated the conditions for a packaging container and packaging body in which the characteristic points of the identifier made up of the printed layer 20 are suitably retained even when imaged with the contents filled. Sample packaging was created by preparing various types of packaging, filling them with a predetermined amount of tap water through the opening, and then sealing the opening with a heat seal. The identifier formed by the printed layer was a predetermined JAN code formed on the laminate constituting the rear surface.

[0023] The fabricated packaging was placed on a stage, and a reference image of each sample was obtained by imaging from behind to include the entire printed layer. Then, the packaging bag was lifted and separated from the stage, and then placed back down, and a matching image of each sample was obtained in the same manner. For each sample, a comparison was performed using a reference image and a matching image to determine if they were identical, and the probability of them not being identified as identical (False-Negative Identification-Error Rate (FNIR)) was calculated. This calculation was performed in accordance with the "Guidance on Individual Management Technology Using Artifact Metrics," [online], January 11, 2022, National Institute of Advanced Industrial Science and Technology (AIST), [Accessed October 30, 2023], Internet (URL: https: / / www.cpsec.aist.go.jp / achievements / artmet / artmet-guidance-1_0_0.pdf). In this study, five samples were prepared for each type of packaging. One image for comparison was obtained for each sample, and 20 comparisons were performed.

[0024] The inventors hypothesized the following four factors as likely to affect identification accuracy and examined their relationship with the aforementioned FNIR. • Ratio of container volume to filling volume (volume of contents) • The German structure of the middle class • Fineness of print layer formation (lines per inch (LPI)) • Percentage of heat-sealable area in the printed layer Table 1 shows the characteristics and FNIR values ​​of each sample used for the study.

[0025] [Table 1]

[0026] In Table 1, "Index" refers to a value calculated based on the following formula, indicating the approximate ratio of the amount of contents filled to the container's volume. Note that the seal area is excluded from the calculation for each dimension, as no contents enter that area. Index = Contents / (Width-to-width dimension × 2) + Height-to-depth dimension Among the samples examined, samples 1, 2, 6, and 7 had an FNIR (log) of -3 or less, confirming that they possess sufficient identification accuracy for practical use. As the LPI value increased, the FNIR(log) tended to decrease. This is thought to be because as the print quality improves, the amount of information that can be extracted as feature points decreases. However, by setting the index to less than 1.0, it was shown that sufficient identification accuracy could be ensured even when the LPI exceeded 100 (Samples 6 and 7). When the index exceeded 1.4, it was observed that the identification accuracy deteriorated sharply even when the LPI value was small (below 100) (Sample 3). This was thought to be due to an increased degree of deformation caused by the contents.

[0027] Regarding the configuration that enhances barrier properties in the intermediate layer, no adverse effects were observed in samples using a transparent barrier layer made of inorganic oxide (Samples 2, 6, and 7). However, in samples using aluminum foil, sufficient identification accuracy could not be obtained regardless of the index or LPI (Sample 4). This was presumed to be because once metal foil is bent, plastic deformation occurs at that point, making it prone to deadholds and resulting in partial information loss in the acquired identifier image.

[0028] Based on the above findings, it was concluded that, in packaging using packaging containers made of flexible packaging materials, individual identification using artificial object metrics can be suitably performed even when using images after the contents have been filled, provided the following conditions are met. • Index less than 1.4 and LPI less than 100 • Index less than 1.0 and LPI less than or equal to 200

[0029] In this study, no clear relationship was found between the proportion of heat-sealed areas in the printed layer and FNIR. As mentioned above, the filled contents do not enter the heat-sealed areas and remain flat after filling, while the unsealed areas curve after filling. Therefore, if both heat-sealed and unsealed areas are present in the printed layer, the laminate 1 may bend strongly at the boundary between them, potentially affecting the identifier image. From this perspective, it is preferable that the entire printed layer consists of either heat-sealed or unsealed areas, or, if both are present, that the proportion of the smaller area is 10% or less.

[0030] An example of the procedure for individual identification using the packaging bag according to this embodiment is shown below. As a prerequisite, it is assumed that feature point information (information indicating feature points) extracted from a reference image is stored in a feature point storage unit provided in a predetermined information processing device. The reference image here is the image used as a reference when performing individual identification.

[0031] As mentioned above, the reference image may be acquired either before or after shipment. Furthermore, the method for extracting feature points from the reference image is arbitrary. For example, image processing techniques to extract contours from an image can be used, and machine learning methods such as deep learning can also be used to extract feature points from the reference image. The feature points extracted from the reference image are stored as numerical feature point data in the feature point storage unit.

[0032] When a user purchases a package, an identifier consisting of the printed layer 20 is captured in an image, and this image (identifier image) is transmitted to an information processing device, allowing for actions such as entering a campaign. In such cases, the individual identification unit provided in the information processing device performs individual identification of the identifier image. If feature point information corresponding to an identifier image is stored in the feature point storage unit, it can be determined, for example, that the item purchased by the user was shipped through a legitimate distribution route and that the user is eligible to participate in the campaign.

[0033] Alternatively, as an entry for a product campaign, the user who purchased the product captures an image of the identifier attached to the product using their smartphone or other device, and transmits it to the information processing device. The feature points of the identifier extracted from the first entry image are stored in the feature point storage unit as registered feature point data. Subsequently, if it is found that the entry image used for the entry (referred to as the second entry image) has the same feature points as the registered feature point data, it can be considered that the entry for the first entry image has already been submitted, and the entry for the second entry image can be rejected. In this case, the first entry image functions as a reference image, and the database in the feature point storage unit is gradually built up by user entries, while artificial object metrics can prevent fraud such as duplicate entries.

[0034] Of course, the individual identification method according to this embodiment can be used for purposes other than campaign entries, and can also be applied, for example, to determining the authenticity of high-end goods where counterfeiting is known or suspected. Individual identification can be performed based on the similarity of feature points, and the threshold can be set appropriately depending on the purpose.

[0035] Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and modifications and combinations of the configuration that do not depart from the spirit of the present invention are also included. For example, in the laminate according to the present invention, it is easier to manufacture if the heat seal layer is provided over the entire surface, but this is not essential, and it may be formed only on the parts that are heat-sealed when the packaging bag is formed. In this case, a part of the printed layer may not be covered by the heat seal layer. [Explanation of Symbols]

[0036] 1. Laminate 10 Base material 20 printing layer 30 Heat seal layer 51. Standing pouch (packaging container)

Claims

1. A package in which contents are filled into a flexible packaging container formed by heat-sealing a laminate, The laminated body is A resin base material, A printed layer formed on the substrate, It has a heat seal layer that covers at least a portion of the printed layer, The resolution of the aforementioned printing layer is 100 or less as LPI, and the index calculated based on the following formula is less than 1.

4. packaging. (Formula) ... Index = Volume of contents (mL) / (Dimensions of the packaging container in the left-right direction excluding the heat-sealed area (mm) × 2 + Dimensions of the packaging container in the up-down direction excluding the heat-sealed area (mm))

2. A package in which contents are filled into a flexible packaging container formed by heat-sealing a laminate, The laminated body is A resin base material, A printed layer formed on the substrate, It has a heat seal layer that covers at least a portion of the printed layer, The resolution of the aforementioned printing layer is 200 or less as LPI, and the index calculated based on the following formula is less than 1.

0. packaging. (Formula) ... Index = Volume of contents (mL) / (Dimensions of the packaging container in the left-right direction excluding the heat-sealed area (mm) × 2 + Dimensions of the packaging container in the up-down direction excluding the heat-sealed area (mm))

3. The laminate further comprises an intermediate layer between the substrate and the heat seal layer, etc. The intermediate layer has a gas barrier layer made of an inorganic oxide, The packaging according to claim 1 or 2.

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