Packaging bag and method for manufacturing the same

Abstract

The packaging bag allows for the arbitrary designation of sections that serve as easily removable pathways. [Solution] A packaging bag having a laminate material comprising a first packaging film 2, a first ink layer 30 of a laser-printable ink composition laminated on the first packaging film 2, and an adhesive layer 310 in contact with the first ink layer 30, wherein a channel portion 32 is provided in a part of the first ink layer 30 that partially peels off to form a channel.

Description

Technical Field

[0001] The present invention relates to a packaging bag having a portion with adjusted adhesiveness. It also relates to a method for manufacturing such a packaging bag.

Background Art

[0002] Packaging bags are used as a means for packaging various items. Packaging bags are appropriately sealed with the contents contained therein for storage, transportation, etc. On the other hand, at the time of use, the adhesiveness and the like are also designed so that they can be opened to take out the contents.

[0003] This adhesiveness may also be designed step by step at the time of use. For example, in the case of retort foods, etc., when heating in a microwave oven, a portion for venting steam may be provided. Also, in some cases, reactive components are separated and stored in a plurality of storage parts, and when in use, a conduction part for connecting each storage part is formed, and a two-chamber separation or the like in which these are mixed and used is carried out. For example, the following documents are disclosed.

[0004] Patent Document 1 discloses an automatic ventilation packaging bag characterized in that a part or all of the upper part of the bottom seal part 4 is adhered with an adhesive strength smaller than the adhesive strength between the inner surface of the packaging bag body 1 and the bottom seal part to form an opening seal part 5, and a ventilation hole 3 is formed in the packaging bag body at a position where the upper part of the ventilation hole contacts the upper end edge of the bottom seal part or at a position above this position and is normally blocked by a bottom member 2, and when the pressure inside the packaging bag becomes a predetermined pressure or more, the opening seal part of the bottom member peels off from the packaging bag body to open the ventilation hole.

[0005] Patent Document 2 discloses a packaging bag in which a pair of sheets (1a, 1b) are joined together and their periphery is sealed, and a weak seal portion (1d) is formed at the boundary between them in order to form a pair of adjacent storage chambers (2, 3), characterized in that in one storage chamber (3), a gas vent hole (3a) is formed in one sheet (1a), and a lid piece (4) made of a breathable film is adhered to cover the gas vent hole (3a).

[0006] Patent Document 3 discloses a packaging bag in which the space of a bag, which is sealed by fusing the periphery of films together, is divided into multiple sections by a divided seal section, characterized in that the outer seal section uses a resin layer made of a material that has affinity with the fusing resin layer of the film constituting the bag, and a part of the divided seal is made into an opening, with a resin layer that does not have affinity with the fusing resin provided at the opening. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2000-159276 [Patent Document 2] Published Utility Model Gazette No. 4-38951 [Patent Document 3] Japanese Patent Publication No. 2013-166579 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] As shown in Patent Documents 1-3, etc., packaging sometimes requires the provision of areas with adjusted adhesive properties. Such adhesive strength is adjusted by the materials used, etc. Adjusting such adhesive properties requires the use of special seal shapes and delicate adjustment of sealing conditions. Furthermore, while it is possible to partially reduce adhesive properties by changing the material, seal shape, and sealing conditions according to the packaging specifications, it is difficult to further adjust the strength of the adhesive properties. However, in some cases, it is necessary to adjust the adhesive properties as appropriate due to changes in the contents or method of use, in which case it is necessary to review the entire design, and it may not be possible to find suitable conditions. Under these circumstances, the present invention aims to provide a packaging bag and a method for manufacturing the same in which areas that become easily peelable flow channels can be arbitrarily set. [Means for solving the problem]

[0009] The inventors of this invention have conducted extensive research to solve the above problems and have found that the following invention is suitable for the above purpose, leading to the present invention. That is, the present invention relates to the following invention.

[0010] <1> The first packaging film, The first ink layer of the laser-printable ink composition laminated on the first packaging film, A method for manufacturing a packaging bag using a laminate material having an adhesive layer in contact with the first ink layer, A method for manufacturing a packaging bag, comprising the step of providing a channel portion in the first ink layer, which becomes a channel when the first ink layer is peeled off by irradiating it with a laser to reduce its adhesiveness. <2> The laser-printable ink composition contains titanium dioxide and a colorant, and the laser is an ultraviolet laser. <1> The method for manufacturing the packaging bags described above. <3> The laminate material comprises a first packaging film, a first ink layer of a laser-printable ink composition laminated on the first packaging film, and an adhesive layer in contact with the first ink layer, wherein a portion of the first ink layer When the adhesive properties are reduced by laser irradiation and partially peeled off.A packaging bag having a flow path portion that serves as a flow path.

Advantages of the Invention

[0011] According to the present invention, a portion that serves as an easily peelable flow path can be arbitrarily set in the packaging bag.

Brief Description of the Drawings

[0012] [Figure 1] It is a schematic view of a laminate according to an embodiment. [Figure 2] It is a schematic view of another laminate according to an embodiment. [Figure 3] It is a schematic view of another laminate according to an embodiment. [Figure 4] It is a manufacturing flow chart of a packaging bag according to an embodiment. [Figure 5] It is a partial cross-sectional view for explaining a packaged state according to an embodiment. [Figure 6] It is a schematic view of a packaging bag according to an embodiment. [Figure 7] It is a schematic view of another packaging bag according to an embodiment. [Figure 8] It is a schematic view of a packaging bag for explaining a test method of an example. [Figure 9] It is a graph showing test results of an example.

Modes for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described in detail. However, the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention, and the present invention is not limited to the following contents unless the gist thereof is changed. In this specification, when the expression "~" is used, it is used as an expression including the numerical values before and after it.

[0014] [The Packaging Bag of the Present Invention] The packaging bag of the present invention has a laminate material including a first packaging film, a first ink layer of a laser-printable ink composition laminated on the first packaging film, and an adhesive layer contacting the first ink layer, and has a channel-forming portion that serves as a channel when the adhesiveness of a part of the first ink layer is reduced and peeled off.

[0015] [Manufacturing Method of the Present Invention] The manufacturing method of the packaging bag of the present invention is a manufacturing method of a packaging bag using a laminate material including a first packaging film, a first ink layer of a laser-printable ink composition laminated on the first packaging film, and an adhesive layer contacting the first ink layer, and includes a step of providing a channel-forming portion that serves as a channel when the adhesiveness is reduced by irradiating the first ink layer with a laser and peeled off. The manufacturing method of the packaging bag of the present invention may be simply referred to as "the manufacturing method of the present invention".

[0016] In the packaging bag of the present invention and the manufacturing method of the present invention, the formed channel-forming portion easily peels off partially and becomes a portion that forms a channel through which gas, liquid, etc. can pass. In the present application, the packaging bag of the present invention can also be obtained by the manufacturing method of the present invention, and the corresponding configurations can be used mutually.

[0017] The inventors have found that the adhesiveness of the adhesive portion of a packaging bag can be easily changed by using an ink layer for printing by UV laser irradiation, which has been conventionally used as a technique for printing on a packaging bag. The present invention is based on such experimental findings.

[0018] [Laminate Material] FIG. 1 is a schematic view of a laminate material according to an embodiment. FIG. 2 is a schematic view of another laminate material according to an embodiment. FIG. 三 is a schematic view of another laminate material according to an embodiment. FIG. 4 is a manufacturing flowchart of a packaging bag according to an embodiment. FIG. 5 is a partial cross-sectional view for explaining a packaging state according to an embodiment. FIGS. 6 and 7 are schematic views of a packaging bag according to an embodiment.

[0019] The packaging bag of the present invention uses a laminate material. The laminate material comprises a first packaging film, a first ink layer, and an adhesive layer. In Figures 1 to 3, the first packaging film, the first ink layer, and the adhesive layer are laminated in that order. However, the laminate material used in the packaging bag of the present invention also includes variations in which the adhesive layer and the first ink layer are laminated in the order of first packaging film, adhesive layer, and first ink layer. The first packaging film and the first ink layer are laminated directly and / or indirectly, and the first ink layer is in contact with the laminated adhesive layer. The adhesive layer and the first ink layer are laminated with a second packaging film, etc., to create a sealed state by bonding during storage, etc. It is preferable that the adhesive layer be positioned to cover the first ink layer in order to ensure sufficient adhesion. A flow channel section is provided in the layer between the first ink layer and the adhesive layer. This flow channel section has reduced adhesion and is easy to peel off, allowing for easy formation of a flow channel when the packaging bag is used.

[0020] [First packaging film] The first packaging film is a packaging film that serves as a base material for the laminate. The packaging film can be a thermoplastic resin film, etc. As thermoplastic resins, films such as polyethylene, polypropylene, polyester, nylon, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polycarbonate, ethylene-vinyl acetate copolymer, and ethylene-vinyl alcohol copolymer can be used. Preferably, it is preferable to use a film that includes stretched polypropylene, polyester, or nylon. The film may be a single thermoplastic resin film, or a laminated film which is a composite of multiple thermoplastic resins or other materials may be used.

[0021] In the present invention, laser irradiation of the laminate material can be performed from any direction relative to the position where the flow channel section is to be provided, after the laminate material has been appropriately bonded or otherwise assembled. Depending on the shape of the packaging bag and the manufacturing process, the laser for providing the flow channel section may be irradiated from the side of the first packaging film, or from the opposite side of the first packaging film, such as a second packaging film. Since the laser may also be irradiated from the side of the first packaging film, it is preferable that the first packaging film is transparent to the laser. The thickness and shape of the first packaging film are designed as appropriate depending on the purpose of packaging and the materials used. The thickness can be, for example, 5 μm to 1000 μm, 10 to 500 μm, or 20 to 300 μm.

[0022] [First ink layer] The first ink layer is a layer of laser-printable ink composition laminated on the first packaging film. The laser-printable ink composition is an ink composition that can be printed on by irradiating it with a laser. Such ink compositions are commonly used for packaging, and examples of such compositions are disclosed in Japanese Patent Publication No. 2005-186507, which contains a resin that develops color when irradiated with a laser beam, Japanese Patent Publication No. 2015-189008, which is an ink composition that changes color when irradiated with a laser, and Japanese Patent Publication No. 2007-168847, which is a date printing ink layer in which a color-developing agent-containing ink layer and a white ink layer are laminated.

[0023] In the present invention, the first ink layer is a layer formed by laminating a laser-printable ink composition by printing, coating, or the like. The ink layer may be a single layer or a multilayer structure consisting of two or more layers.

[0024] Ink compositions that change color upon laser irradiation include colored inks such as white ink, and laser-developable inks containing a color-developing agent that produces color upon laser irradiation. The ink layer may consist solely of a colored ink such as white ink.

[0025] Suitable colored inks include ink compositions containing inorganic oxides and binder resins. Suitable inorganic oxides include titanium dioxide, magnesium oxide, zinc oxide, aluminum oxide, silicon dioxide, and mixtures thereof. In particular, white inks containing titanium dioxide, a white pigment, are preferred.

[0026] The ink composition may optionally contain a binder resin. Any conventionally known resin can be used as the binder resin. For example, acrylic resins, vinyl chloride-vinyl acetate copolymers, polyester resins, cellulose resins, polyurethane resins, chlorinated polypropylene resins, etc., can be used individually or in combination of two or more.

[0027] The ink composition can suitably use any white ink conventionally used as a printing substrate. For example, the composition can have a mass ratio of inorganic oxide to binder resin of 70:30 to 90:10, more preferably 75:25 to 85:15.

[0028] These components can be mixed with a solvent as needed and printed or coated onto a first packaging film or the like to form a first ink layer. Examples of solvents that can be used in the ink composition include organic solvents such as ethanol, isopropyl alcohol, methyl acetate, n-propyl acetate, methyl ethyl ketone, methyl isobutyl ketone, 1-methoxy-2-propanol, toluene, and xylene.

[0029] In addition to inorganic oxides and binder resins, colored inks may also contain color-developing agents that develop color upon laser irradiation. Examples of such color-developing agents include leuco dyes such as fluorane, phenothiazine, spiropyran, triphenylmetaphthalide, and rhodamine lactam. Specific examples of leuco dyes include 3,3-bis(p-dimethylaminophenyl)phthalide, 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide, 3,3-bis(p-dimethylaminophenyl)-6-aminophthalide, 3,3-bis(p-dimethylaminophenyl)-6-nitrophthalide, 3,3-bis(p-dimethylaminophenyl)phthalide, 3,3-bis(3-dimethylamino)-7-methylfluorane, 3-diethylamino-7-chlorofuran, 3-diethylamino-6-chloro-7-methylfluorane, 3-diethylamino-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, and 3-piperidino-6-methyl-7-anilinofluorane.

[0030] In addition, examples of colorants include molybdenum and inorganic compounds containing metals such as iron, copper, nickel, chromium, zirconium, antimony, and bismuth, such as bismuth oxide.

[0031] If the ink composition contains a coloring agent, its content is in the range of 0.1 to 95.0% by mass in terms of solid content relative to the total mass of the ink layer. In the present invention, the content of the coloring material is preferably 1 to 30% by mass. If the content is low, the adhesiveness adjustment effect may not be easily achieved. There is little need to increase the content excessively, and an upper limit may be set due to the effect on surrounding layers and the effect of laser irradiation.

[0032] The ink composition may contain any additives as needed. For example, anti-blocking agents and curing agents may be added to reduce the laminate strength. Silane coupling agents may also be added to increase the laminate strength. Other additives such as pigment dispersants, defoamers, leveling agents, waxes, preservatives, rust inhibitors, plasticizers, flame retardants, and color developers may also be added. The type and amount of these additives can be appropriately selected depending on the printing method, application conditions, substrate, printing conditions, application conditions, etc.

[0033] The thickness of the ink layer can be adjusted as needed, but for example, the amount of ink composition applied, as a dry coating amount, is 1.0 to 10.0 g / m². 2 Yes, 1.5~8.0g / m 2 Yes. If the ink layer is too thick, it may have a significant impact on the surrounding layers. If the ink layer is too thin, the effect of adjusting adhesion may be insufficient.

[0034] The method for laminating the ink layers is not particularly limited, but methods such as inkjet, immersion, spin coating, and printing can be used. In the present invention, lamination by printing is preferred.

[0035] [Adhesive layer] The adhesive layer is a layer containing adhesive components that comes into contact with the first ink layer. The adhesive layer is for bonding the first packaging film to a second packaging film, etc., and can be formed using a laminating adhesive used for laminating packaging films. The adhesive layer can also be formed so as to cover the periphery of the first ink layer.

[0036] Suitable laminating adhesives for use in lamination include ester-based adhesives, urethane-based adhesives, vinyl-based adhesives, acrylic-based adhesives, epoxy-based adhesives, and the like. Any heat-sealable resin may also be used.

[0037] The laminate material may have layers other than the first packaging film, the first ink layer, and the adhesive layer, such as an optional masking layer, barrier layer, printing layer, or printed layer. The first ink layer of the present invention uses a laser-printable ink composition, but in order to form a flow channel, it may also have layers that are part of which are printed with various information, or layers for general labeling of the packaging, or layers for masking to appropriately emphasize or block various parts, or a barrier layer to adjust transparency.

[0038] [Second type of packaging film] The second type of packaging film is a film laminated to a laminating material. The second type of packaging film can be pre-laminated to the laminating material to form a packaging bag or a sealing component for packaging, or it can be laminated during the sealing of the packaging bag.

[0039] [Adhesive part] The adhesive section is the part used to bond the laminate material to a second packaging film or packaging container. Typically, the adhesive section ensures that the ink composition and adhesive layer are firmly attached to the film, resulting in sufficient bonding strength. Furthermore, it is a section with stronger adhesive strength than the flow channel section.

[0040] [Flow channel section] The channel section is provided in a part of the first ink layer and selectively reduces its adhesion compared to the surrounding adhesive area, forming a channel when peeled off. This channel section is formed by utilizing a low-adhesion area created by irradiating at least a portion of the first ink layer of the laminate film with a laser to reduce the adhesion of the adhesive layer. The channel section is a part that is provided so as to form a channel from the inside of the packaging bag. The channel section can be sealed during normal storage of the packaging bag because it retains its adhesive properties.

[0041] The delamination of the channel section to create a channel occurs due to pressure applied to the surrounding area where the channel section is located. For example, when a packaging bag is pressurized or heated, vapor pressure is generated, the contents move, or tension is applied to separate the film around the channel section. Due to the low adhesion, the channel section selectively delaminates. This is based on the finding that when laser printing, such as with a UV laser, is used to change the ink color, the discolored ink area selectively loses its adhesive strength to the film, and this decrease in adhesive strength leads to a decrease in heat seal strength.

[0042] The channel portion can be formed by a process in which the first ink layer is irradiated with a laser to reduce its adhesion, thereby creating a channel portion that becomes a channel when the layer is peeled off. The laser irradiation for creating the channel portion can be the same as the conditions used when printing on a laser-printable ink composition with laser irradiation. By irradiating with a laser at an intensity and duration equivalent to or greater than that used when printing, the adhesion can be reduced.

[0043] The laser irradiation conditions can be appropriately set based on the design of the first ink layer and the ease of peeling of the flow channel section. For laser irradiation for printing, YVO4 (yttrium vanadate) laser beams (wavelength peaks around 1060 nm and 1064 nm), green lasers (wavelength peak around 532 nm), and fiber lasers (wavelength peak around 1090 nm) are widely used because they allow for fine control of the energy amount and have high transmittance to transparent films.

[0044] Laser irradiation, especially in single-mode where the power peak is concentrated at the center of the beam, can efficiently reduce adhesion. These lasers have the property of penetrating transparent materials, suppressing the generation of smoke during printing, and allowing for adjustment of color density and the effect on the film. As a result, it is possible to form a channel without holes or other defects.

[0045] The flow channel section is a part formed by laser irradiation in a linear, strip-like, or dot-like shape to serve as a flow channel. Flow channels are provided in areas such as flow channels from inside the packaging bag to the outside, or sections that connect adjacent compartments of packaging via adhesive joints.

[0046] [Using laminating film] The packaging bag of the present invention can be used to contain any contents, such as food, pharmaceuticals, clothing, cosmetics, daily necessities, home appliances, precision machinery, electronic equipment, and industrial products.

[0047] [Packaging bag] The packaging bag can be any form of packaging using laminate material. For example, it can be a bag shape or a tray sealed with laminate material. If it is a bag shape, it can be appropriately laminated with a second packaging film or other film to create a shape that can hold the contents according to its intended use, such as a flat bag, gusseted bag, pillow packaging bag, or standing pouch.

[0048] The packaging bag of the present invention can be used, for example, as a packaging bag for microwave ovens or as a two-compartment separate container that is separated during storage and mixed before use. Such packaging bags require a partial reduction in seal strength. Microwave oven packaging materials are provided with vents to allow steam generated when heated in a microwave oven to escape, and the flow channel portion of the packaging bag of the present invention can be designed to serve as these vents. In the case of a two-compartment separate container, it can be used for packaging in which the contents of each compartment, which are separated during storage, are moved through a flow channel and mixed before use.

[0049] Figure 5 is a partial cross-sectional view illustrating the packaging state according to the embodiment. The present invention relates to a laminate material comprising a first packaging film 2, a first ink layer 30, an adhesive layer 310, and a second packaging film 4. By irradiating at least a portion of the area where the first ink layer 30 and the adhesive layer 310 are laminated with a laser, a channel portion 32 can be formed. Since the adhesion is selectively reduced in the laser-irradiated area, the entire area where the first ink layer 30 is provided may be irradiated with a laser to form a channel portion 32, or the channel portion 32 may be formed by partially irradiating with a laser to modify the adhesion for design purposes. In the area where the adhesive layer 310 is not laminated with the first ink layer 30, and the first packaging film 2 and the second packaging film 4 are laminated together, this becomes an adhesive portion that directly bonds the first packaging film 2 and the second packaging film 4.

[0050] Figure 6 shows an example of a packaging bag using laminate material. Figure 6(a) is a schematic diagram of the packaging in plan view, and Figure 6(b) is a schematic cross-sectional view in the side view. The packaging bag 11 can be used as a packaging bag for microwave ovens, etc. A first packaging film 2 and a second packaging film 4 are bonded together at an adhesive portion 31. A channel portion 32 is provided in a part of this adhesive portion 31, which is formed by irradiating a laser onto the portion where a first ink layer of a laser-printable ink composition and an adhesive layer are laminated. In this packaging bag 11, the portion of the channel portion 32 provided inside the adhesive portion 31 uses a laminate material having a first ink layer of a laser-printable ink composition laminated on the first packaging film 11 and an adhesive layer in contact with the first ink layer. Furthermore, by providing another backing film 6 on the back side and sealing the perimeter, it can be used as packaging for containing contents.

[0051] The packaging bag 11 is sealed during storage by providing a strip-shaped adhesive section 31 at the overlapping portion of the first packaging film 2 and the second packaging film 4. The flow channel section 32 is provided as a flow channel at the top and bottom of a portion where the adhesiveness has been reduced. Because the adhesiveness of the flow channel section 32 is reduced, when contents that generate steam due to heating are placed inside, the air pressure generated when processed in a microwave oven, etc., and the fluidity of the gas selectively separate the top and bottom of the flow channel section 32 within the adhesive section 31, forming a flow channel. Steam is released from this flow channel, preventing the packaging bag 11 from bursting.

[0052] Figure 7 shows an example of a packaging bag using laminate material. Figure 7(a) is a schematic diagram of the packaging in plan view, and Figure 7(b) is a schematic cross-sectional view in the front view. The packaging bag 12 can be used for two-compartment packaging. The packaging bag 12 has a first packaging film 2 on the front surface and a second packaging film 4 on the back surface, and the perimeter is sealed. An adhesive section 33 is provided in the center of the packaging bag 12, and the first packaging film 2 and the second packaging film 4 are also bonded in the center. As a result, the inside of the packaging bag 12 is separated into two compartments, with the first compartment 51 formed on the left side of Figure 7 and the second compartment 52 formed on the right side. A first ink layer is laminated on a part of the inside of the adhesive layer 33, and a flow channel section 34 is formed by laser irradiation of the first ink layer.

[0053] In the packaging bag 12, the first chamber 51 and the second chamber 52 are separated by the adhesive portion 33 during storage, so the contents of each chamber do not come into contact with each other, and reactions can be prevented. On the other hand, the packaging bag 12 has reduced adhesive strength at the flow channel portion 34, making it easy to peel off. Therefore, when the first chamber 51 and / or the second chamber 52 are compressed during use, pressurizing the contents of each chamber to flow into the other chamber causes the area around the flow channel portion 34 to selectively peel off, creating a flow channel between the chambers. This allows the contents of each chamber to be mixed and reacted within the packaging bag 12. [Examples]

[0054] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples unless its essence is changed.

[0055] [Manufacturing of laminate materials] A laminate material was manufactured having a portion laminated in the following order: film (A1), adhesive (1), film (A2), white ink, adhesive (2), and film (B1). First, film (A1), adhesive (1), and film (A2) were pre-laminated to form a front-side laminate film. A portion between this front-side laminate film and film (B1) was coated with white ink and adhesive (2), and the bonded portion was used for the adhesion test described later. • Film (A1): "Barrier NY #15 (Transparent)" Unitika Ltd. "HG (Transparent)" Thickness 15 μm • Adhesive (1): Rock Paint Co., Ltd. “RU40 (main component) / H-4S (hardener)” Film (A2): "NY#15 (Transparent)" Kojin Film & Chemicals Co., Ltd. "Bonil W (Transparent)" Thickness 15μm • White ink: Sakata Inx Co., Ltd. "Bellcolor" containing titanium dioxide • Adhesive (2): Rock Paint Co., Ltd. “RU40 (main component) / H-4S (hardener)” Film (B1): "CPP#50 (Transparent)" Toray Film Processing Co., Ltd. "ZK207 (Transparent)" Thickness 50μm

[0056] [Formation of the channel section] Using Keyence Corporation's "FP1000" as the processing machine, the areas coated with white ink / adhesive (2) were irradiated with a UV laser under the following processing conditions. • Frequency 60kHz 90% • Scan speed: 2000 mm / s • Irradiation from the Barrier NY side ·Irradiation distance: 30mm It should be noted that these conditions are assumed to have a higher frequency and energy intensity than typical printing conditions, and all other conditions are also assumed to involve stronger irradiation.

[0057] Figure 8 is a schematic diagram of a packaging bag used to illustrate the test method of the embodiment. As shown in the upper part of Figure 8(a), the sample for the comparative test was laminated without laser irradiation, as the part for measuring adhesive strength. Also, as shown in the upper part of Figure 8(b), the sample for this embodiment was processed to create a flow channel section by intermittently irradiating the portion with a vertical laser in the area having the white ink layer and the adhesive (2) layer with a low-adhesion section.

[0058] Furthermore, without a white ink layer, a laminate film for the front side and a film laminated with film (B1) using only adhesive (2) were prepared for comparative testing (Figure 8(a) bottom). In this comparative test film, similar to the sample for this embodiment described above, areas with adhesive (2) layer were intermittently subjected to vertical laser irradiation (Figure 8(b) bottom).

[0059] [Measuring adhesive strength] Using a Shimadzu Corporation "Autograph" test strip, the peel force was measured when pulling the front-side laminate film and film (B1) in the direction of separation, using a test piece with a width of 15 mm and a test length of approximately 60-70 mm.

[0060] Figure 9 is a graph showing the test results of the example. In Figure 9, the horizontal axis represents stroke (mm), and the vertical axis represents peeling force (N). Graph A in the upper section shows the result with a white ink layer. When laser irradiation is not performed (no UV irradiation), the adhesive strength is equivalent. On the other hand, in the sample used in this implementation example, it was confirmed that the adhesive strength was selectively reduced along the areas where intermittent vertical laser irradiation was performed (with UV irradiation). Graph B in the lower section shows a sample without a white ink layer. There was no difference in adhesion regardless of whether laser irradiation was used or not (with UV irradiation, without UV irradiation).

[0061] Furthermore, the areas irradiated with the white ink changed to a color close to black. If it is necessary to make this black area invisible, printing in a color close to black can be done on the front side after laser irradiation. In this way, by irradiating a packaging bag that has been pre-printed with white ink with a UV laser and designing the irradiation area, the adhesive strength and seal strength can be partially controlled. [Industrial applicability]

[0062] This invention can be used in packaging and is industrially useful. [Explanation of Symbols]

[0063] 11, 12 Packaging bag 2. First packaging film 30 First ink layer 310 Adhesive layer 31, 33 Adhesive part 32, 34 Flow channel section 4. Second packaging film 51 Room 1 52 Second room 6. Backside film

Claims

1. The first packaging film, The first ink layer of the laser-printable ink composition laminated on the first packaging film, A method for manufacturing a packaging bag using a laminate material having an adhesive layer in contact with the first ink layer, A method for manufacturing a packaging bag, comprising the step of providing a channel portion in the first ink layer, which becomes a channel when the first ink layer is partially peeled off by irradiating it with a laser to reduce its adhesiveness.

2. The method for manufacturing a packaging bag according to claim 1, wherein the laser-printable ink composition contains titanium dioxide and a colorant, and the laser is an ultraviolet laser for printing.

3. A packaging bag comprising a laminate material having a first packaging film, a first ink layer of a laser-printable ink composition laminated on the first packaging film, and an adhesive layer in contact with the first ink layer, wherein a portion of the first ink layer has a channel portion that becomes a channel when its adhesiveness is reduced by laser irradiation and it is partially peeled off.

Images