Laminates and packaging bags

Abstract

The present invention provides laminates and packaging bags that offer excellent tearability and reduce the amount of dissimilar materials other than polyethylene resins used. [Solution] A laminate 10 having a half-cut portion 11 formed thereon, the laminate 10 having in this order a base layer 12 made of polyethylene resin, an extruded resin layer 13 made of polyethylene resin, and a sealant layer 14 made of polyethylene resin, the half-cut portion 11 is formed by removing at least a part of the thickness direction of the base layer 12 by laser irradiation without penetrating the laminate 10 in the thickness direction, an anchor coat layer 15 with a thickness of 10 nm to 2.5 μm is provided on the surface of the extruded resin layer 13 on the base layer 12 side, and the half-cut portion 11 does not reach the anchor coat layer 15, the extruded resin layer 13, and the sealant layer 14.

Description

Technical Field

[0001] The present invention relates to a laminate and a packaging bag.

Background Art

[0002] Regarding the collection of plastic containers and packaging after use, packaging bags containing two or more types of resins have a problem that they are difficult to recycle as plastic containers and packaging. To facilitate recycling, monomaterial containers and packaging using a single resin have been proposed. For example, Patent Document 1 describes a packaging bag in which half-cut lines are formed by laser irradiation on a monomaterial of a polyolefin-based resin (preferably a polyethylene-based resin).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a laminate and a packaging bag that have excellent hand tearability and can reduce the amount of different materials other than polyethylene-based resins used.

Means for Solving the Problems

[0005] The present invention includes the following aspects. [1] A laminate having a half-cut portion, wherein the laminate comprises, in this order, a base layer formed from a polyethylene resin, an extruded resin layer formed from a polyethylene resin, and a sealant layer formed from a polyethylene resin, the half-cut portion being formed by removing at least a portion of the base layer in the thickness direction by laser irradiation without penetrating the laminate in the thickness direction, an anchor coat layer with a thickness of 10 nm to 2.5 μm provided on the surface of the extruded resin layer facing the base layer, and the half-cut portion not reaching the anchor coat layer, the extruded resin layer, and the sealant layer. [2] The laminate according to [1], characterized in that the base material layer includes an stretched polyethylene resin layer. [3] The laminate according to [1] or [2], wherein the laminate comprises an intermediate layer made of polyethylene resin between the base material layer and the anchor coat layer, and the half-cut portion is formed to a part in the thickness direction of the intermediate layer. [4] The laminate according to [3], characterized in that the laminate comprises at least one selected from the group consisting of an adhesive layer and a printed layer between the base material layer and the intermediate layer. [5] The laminate according to [3] or [4], characterized in that the intermediate layer includes an stretched polyethylene resin layer. [6] A packaging bag having a half-cut portion formed in the opening portion, wherein the laminate having the half-cut portion in the opening portion is made of the laminate described in any one of [1] to [5]. [7] The packaging bag according to [6], characterized in that it is a refill pouch. [8] The packaging bag according to [6] or [7], characterized in that it is a standing pouch. [Effects of the Invention]

[0006] According to the present invention, it is possible to achieve excellent tearability by hand and reduce the amount of dissimilar materials other than polyethylene resin used. [Brief explanation of the drawing]

[0007] [Figure 1] This is a cross-sectional view showing an example of a laminate having a half-cut section. [Figure 2] This is a front view showing an example of a packaging bag. [Modes for carrying out the invention]

[0008] The present invention will be described below based on preferred embodiments. Figure 1 is a cross-sectional view showing an example of a laminate having a half-cut portion. Figure 2 is a front view showing an example of a packaging bag. The drawings are for illustrative purposes only, and the dimensions, proportions, etc. of the components may differ from those of the actual product.

[0009] The laminate 10 of this embodiment has a half-cut portion 11. In addition, the packaging bag 20 of this embodiment has a half-cut portion 11 (see Figure 1) formed on the laminate (specifically the body member 21) used in the opening portion 24 (see Figure 2). In the laminate 10 (body member 21 of the packaging bag 20) having a half-cut portion 11, a part of the laminate 10 is removed by laser irradiation to form the half-cut portion 11.

[0010] The laminate 10 has a base layer 12 made of polyethylene resin. At least a portion of the base layer 12 in the thickness direction is removed by a half-cut portion 11 that does not penetrate the laminate 10 in the thickness direction. Furthermore, the laminate 10 has an extruded resin layer 13 made of polyethylene resin and a sealant layer 14 made of polyethylene resin. The extruded resin layer 13 is laminated on the surface of the sealant layer 14 that faces the base layer 12.

[0011] The laminate 10 has, in the thickness direction, a base layer 12, an extruded resin layer 13, and a sealant layer 14 in this order. Before the half-cut portion 11 is formed, the base layer 12, the extruded resin layer 13, and the sealant layer 14 may be laminated with substantially uniform thickness over the entire surface of the laminate 10. The half-cut portion 11 is formed only on a part of the base layer 12 side, without penetrating the laminate 10 in the thickness direction.

[0012] In the laminate 10 of this embodiment, not only are the base layer 12 and the sealant layer 14 polyethylene resin layers, but the extruded resin layer 13 is also a polyethylene resin layer. This increases the proportion of polyethylene resin contained in the laminate 10, thereby reducing the amount of other materials used (by weight ratio in the laminate 10) other than polyethylene resin.

[0013] As described above, the half-cut portion 11 is formed to remove at least a portion of the base material layer 12 in the thickness direction by laser irradiation. By providing the half-cut portion 11, it is possible to provide easy cutting by tearing and tearing by hand without using a blade.

[0014] The laser used is not particularly limited as long as it is used for processing resins such as films, but examples include solid-state lasers, gas lasers, fiber lasers, semiconductor lasers, and excimer lasers. The wavelength of the laser can be in the infrared region, the visible light region, or the ultraviolet region. For example, a CO2 laser is preferred because its output wavelength is in the infrared region, which is a relatively long wavelength of about 9 to 11 μm, and it has excellent resin processing properties.

[0015] When a long-wavelength laser is irradiated onto the film, the film heats up locally at the irradiated area, and a portion of the resin is removed. By removing the resin in a narrow width, a linear half-cut section 11 is formed. The half-cut section 11 may be a continuous line in the length direction, or it may be a broken or dotted line that is discontinuous in the length direction. The length direction of the half-cut section 11 may be straight, curved, or bent.

[0016] Since polyethylene-based resins have a relatively simple molecular structure, their infrared absorption wavelength bands are limited, and they are less likely to absorb laser energy. However, polyethylene-based resins have a relatively low melting point, so once energy is absorbed by the material, processes such as melting and cutting can be performed relatively easily. Therefore, by disposing a laser-absorbing material in or near the polyethylene-based resin layer, the polyethylene-based resin layer can be easily processed.

[0017] Conventional laminated films compatible with monomaterials use a polyester-based resin film such as polyethylene terephthalate (PET) as the base material layer. For this reason, the half-cut portion can be easily formed as the polyester absorbs the laser. However, in the case of a monomaterial material mainly composed of a polyethylene-based resin layer, it is necessary to dispose the laser-absorbing material according to the position and depth of the half-cut portion.

[0018] In the laminate 10 of the present embodiment, the anchor coat layer 15 is provided on the surface of the extruded resin layer 13 on the base material layer 12 side, with a thickness of 10 nm or more and 2.5 μm or less. Further, it is preferable that the laser absorbing layer 16 is provided on the base material layer 12 side. The base material layer 12 itself may be the laser absorbing layer 16, but from the viewpoint of reducing the proportion of different materials used, it is preferable to provide the laser absorbing layer 16 separately from the base material layer 12.

[0019] Examples of the laser absorbing layer 16 include at least one selected from the group consisting of a resin layer, an adhesive layer, and a printed layer. Even when the anchor coat layer 16 has laser absorbency, it is preferable to suppress the laser absorption of the anchor coat layer 15. For this reason, it is preferable that the intermediate layer 17 formed of a polyethylene-based resin is laminated between the anchor coat layer 15 and the laser absorbing layer 16. The anchor coat layer 15 and the laser absorbing layer 16 are different materials in the polyethylene-based monomaterial material.

[0020] In the laminate 10 before the half-cut portion 11 is formed, the anchor coat layer 15 and the laser absorbing layer 16 may be laminated over the entire surface of the laminate 10 with a substantially uniform thickness. Furthermore, the intermediate layer 17 may also be laminated over the entire surface of the laminate 10 with a substantially uniform thickness. After the half-cut portion 11 is formed, part of the laser absorbing layer 16 may be removed by the half-cut portion 11. Furthermore, part of the intermediate layer 17 may also be removed by the half-cut portion 11.

[0021] By suppressing laser absorption of the anchor coat layer 15, the half-cut portion 11 does not reach the anchor coat layer 15. Furthermore, since the half-cut portion 11 is formed from the base material layer 12 side, it does not reach the sealant layer 14 and the extruded resin layer 13 either. The half-cut portion 11 preferably does not penetrate through the intermediate layer 17, and may be formed up to a part in the thickness direction of the intermediate layer 17. The half-cut portion 11 may penetrate through the base material layer 12 in the thickness direction. Furthermore, the half-cut portion 11 may be open to the outer surface of the base material layer 12.

[0022] The half-cut portion 11 of the present embodiment does not have improved hand tearability as the depth from the base material layer 12 side increases, and it is desirable that the half-cut portion 11 is formed within an appropriate depth range from the base material layer 12 side. Although the reason for this is not necessarily clear, it is considered to be because the extruded resin layer 13 is formed as an unstretched layer. From this point of view, it is desirable that not only the base material layer 12 but also the intermediate layer 17 have physical properties different from those of the extruded resin layer.

[0023] For example, it is preferable that at least one layer in the group consisting of the base material layer 12 and the intermediate layer 17 includes a stretched polyethylene-based resin layer. Furthermore, both the base material layer 12 and the intermediate layer 17 may be stretched polyethylene-based resin layers. The stretching direction is not particularly limited, and may be the machine direction (MD) or the transverse direction (TD). Biaxial stretching in the MD direction and the TD direction is also acceptable. In the case of biaxial stretching, the degree of freedom in the tearing direction is higher than that of uniaxial stretching. Examples of the stretching ratio include about 2 to 10 times.

[0024] Although not specifically shown in the figures, the laminate 10 may optionally include layers of barrier resins such as ethylene-vinyl alcohol copolymer (EVOH), metals such as aluminum, and inorganic compounds such as silica and alumina. These barrier materials are not limited to metals and inorganic compounds, but also include EVOH. Since they are dissimilar materials in polyethylene monomaterials, it is preferable to form them into thin layers by vapor deposition, co-extrusion, etc. For example, EVOH may be co-extruded into the base layer 12, the intermediate layer 17, or the sealant layer 14. Depending on the application, these barrier layers made of dissimilar materials may be omitted. Examples of barrier properties include oxygen barrier properties and water vapor barrier properties.

[0025] Examples of materials for the base layer 12 include polyethylene resins with relatively high density, such as medium-density polyethylene (MDPE) and high-density polyethylene (HDPE). The base layer 12 may be formed from one type of polyethylene resin, or it may contain two or more types of polyethylene resins. The thickness of the base layer 12 is not particularly limited, but for example, it may be about 10 to 50 μm. If the base layer 12 is a stretched resin layer, it may be uniaxially stretched or biaxially stretched. The base layer 12 is not limited to a single-layer film, but may also be a multilayer film produced by co-extrusion or the like.

[0026] Examples of materials for the intermediate layer 17 include polyethylene resins with relatively high density, such as medium-density polyethylene (MDPE) and high-density polyethylene (HDPE). The intermediate layer 17 may be formed from one type of polyethylene resin, or it may contain two or more types of polyethylene resins. The thickness of the intermediate layer 17 is not particularly limited, but for example, it may be about 10 to 50 μm. If the intermediate layer 17 is a stretched resin layer, it may be uniaxially stretched or biaxially stretched. The intermediate layer 17 is not limited to a single-layer film, but may also be a multilayer film produced by co-extrusion or the like.

[0027] Examples of materials for the extruded resin layer 13 include polyethylene-based resins such as linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), and high-density polyethylene (HDPE), or unstretched polyethylene-based resins. The extruded resin layer 13 may be formed from one type of polyethylene-based resin, or it may contain two or more types of polyethylene-based resins. The thickness of the extruded resin layer 13 is not particularly limited, but for example, it may be about 10 to 50 μm.

[0028] The material of the sealant layer 14 may be a relatively low-density polyethylene resin such as linear low-density polyethylene (LLDPE) or low-density polyethylene (LDPE), or an unstretched polyethylene resin. The sealant layer 14 may be formed from one type of polyethylene resin, or it may contain two or more types of polyethylene resins. It may also be a multilayer structure such as a three-layer structure in which high-density polyethylene (HDPE) is sandwiched between relatively low-density polyethylene resins.

[0029] The thickness of the sealant layer 14 is not particularly limited, but for example, it can be about 50 to 180 μm. The sealant layer 14 may be a single-layer sealant film or a multi-layer sealant film. A multi-layer sealant film can be formed by laminating two or more layers of film-like sealant resin using methods such as co-extrusion, extrusion lamination, sandwich lamination, or heat lamination.

[0030] The polyethylene resin used in the laminate 10 may be an ethylene homopolymer or an ethylene copolymer. Examples of monomers other than ethylene (comonomers) include one or more α-olefins such as 1-butene, 1-hexene, and 1-octene, cyclic olefins such as norbornene, and vinyl monomers such as vinyl acetate, vinyl chloride, and acrylic acid. When comonomers are used in the polyethylene resin, there may be one or more comonomers.

[0031] The proportion of ethylene in the constituent monomers of the polyethylene resin is preferably 50% by weight or more, and may be, for example, 80 to 100% by weight. The polyethylene resin may include resins derived from fossil resources such as petroleum, resins derived from biomass such as plants, or resins obtained through recycling. The material forming the polyethylene resin layer may be one type of polyethylene resin or a blend of two or more types of polyethylene resins.

[0032] The polyethylene resin layer may contain resins or additives other than polyethylene resins. Additives are not particularly limited, but examples include antioxidants, lubricants, antiblocking agents, flame retardants, UV absorbers, light stabilizers, antistatic agents, colorants, crosslinking agents, and compatibilizers. Other resins and additives besides polyethylene resins are considered dissimilar materials in polyethylene monomaterials.

[0033] The material used to form the anchor coat layer 15 is not particularly limited, but examples include urethane compounds, epoxy compounds, isocyanate compounds, polyethyleneimine, and organotitanium compounds such as titanium alkoxide. The thickness of the anchor coat layer 15 is as described above.

[0034] If the laser absorption layer 16 includes an adhesive layer, the adhesive layer may be formed from an adhesive, or from a composite (lamination, etc.) of the adhesive and an anchor coating agent. The material used to form the adhesive layer is not particularly limited, but examples include urethane compounds, epoxy compounds, isocyanate compounds, polyethyleneimine, and organotitanium compounds such as titanium alkoxide. The thickness of the adhesive layer can be, for example, about 0.1 to 10 μm, about 1 to 6 μm, or about 3 to 4 μm.

[0035] If the laser absorption layer 16 includes a printed layer, the printed layer can be formed by printing ink in a solid or patterned manner using printing methods such as gravure printing, letterpress printing, offset printing, screen printing, or inkjet printing. The thickness of the printed layer is not particularly limited, but examples include approximately 0.5 to 10 μm, 1 to 6 μm, or 1 to 4 μm. The printed layer may be formed on the entire surface or a part of the surface of the substrate layer 12 or the intermediate layer 17. Two or more printed layers may be stacked on top of each other. The printed layer may be omitted from the laminate 10.

[0036] The ink used to form the printed layer may contain a coloring agent such as a pigment or dye, and a binder. The binder is not particularly limited, but examples include polyamide, polyurethane, polyester, polyvinyl chloride, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, acrylic polymer, polybutadiene, and cyclocompound rubber. The ink may also contain a solvent such as water, organic solvent, or vegetable oil. After printing, the ink can be dried by the evaporation of the solvent or curing of the ink. Heating, ultraviolet irradiation, electron beam irradiation, etc., may be used to accelerate the drying or curing of the ink.

[0037] The laser absorption layer can also be formed as a solid coating using methods such as die coating or air knife coating. When a resin layer (a different resin other than polyethylene-based resin) is used as the laser absorption layer, it is preferable to form the resin layer thinly, unlike conventional PET substrate films. Examples of laser absorption layer thicknesses include approximately 0.1 to 10 μm, 1 to 6 μm, and 3 to 4 μm.

[0038] It is preferable that the total weight of polyethylene-based resin is 80% or more by weight of the total weight of the laminate 10, and the total weight of dissimilar materials is 20% or less by weight. Furthermore, it is more preferable that the total weight of polyethylene-based resin is 90% or more by weight, and the total weight of dissimilar materials is 10% or less by weight.

[0039] The manufacturing method for the laminate 10 is not particularly limited, but an anchor coat layer 15 may be applied on the intermediate layer 17, the anchor coat agent may be dried, then the extruded resin layer 13 may be laminated, and then it may be laminated with the sealant layer 14. If the intermediate layer 17 is omitted, an anchor coat layer 15 may be applied on the base layer 12, the anchor coat agent may be dried, then the extruded resin layer 13 may be laminated, and then it may be laminated with the sealant layer 14. In extruded lamination, it is preferable to overlap the sealant layer 14 with the extruded resin layer 13 while it is heated and flexible, and then pressurize while cooling. Furthermore, the half-cut portion 11 is formed by laser irradiation after each layer of the laminate 10 has been laminated.

[0040] The laminate 10 of the embodiment can be used to manufacture a packaging bag. It is sufficient that at least the part of the packaging bag that includes an opening portion is formed from the laminate of the embodiment. If the packaging bag has a part that does not include an opening portion, the part that does not include an opening portion may be made of a different laminate than the laminate of the embodiment. It is preferable that the part that does not include an opening portion is also made of a polyethylene monomaterial and is configured in the same way as the laminate 10 of the embodiment. The part that does not include an opening portion does not need to have a half-cut portion 11.

[0041] The packaging bag 20 shown in Figure 2 is a standing pouch formed from a pair of body members 21 and a bottom member 22 folded in half along a fold line 22a. Above the fold line 22a, the front and rear body members 21 are joined by the left and right body seal portions 21a and 21b. The bottom member 22 is sandwiched between the front and rear body members 21 with the fold line 22a facing upwards. Below the fold line 22a, the bottom member 22 is joined to the body member 21 to form the bottom seal portion 22b.

[0042] At least one of the pair of body members 21 is formed from a laminate 10 having a half-cut portion 11 (see Figure 1). If only one of the body members 21 has a half-cut portion 11, the other body member 21 may be formed from a laminate 10 without a half-cut portion 11. The bottom member 22 can also be formed from a laminate 10 without a half-cut portion 11.

[0043] A laminate 10 without a half-cut section 11 may be a laminate 10 in which the material, thickness, etc., of each layer are the same, except for the presence or absence of the half-cut section 11. In addition to the presence or absence of the half-cut section 11, there may also be a laminate 10 in which at least one of the materials, thickness, etc., of each layer is different.

[0044] The illustrated packaging bag 20 has an upper seal portion 23 that closes the space between the front and rear body members 21 at the top of the packaging bag 20. The left and right sides of the storage portion 27 are sealed by the body seal portions 21a and 21b, and the top of the storage portion 27 is left open when the contents C is filled into the storage portion 27. In this case, after the contents C is filled, the filling opening at the top of the storage portion 27 is sealed by the upper seal portion 23.

[0045] The illustrated packaging bag 20 has an opening section 24. The opening section 24 may also have a spout. The spout of the opening section 24 has a flow path 25 formed from the unsealed portion between the body members 21 at the top of the packaging bag 20, and flow path forming seal sections 25a and 25b formed along the flow path 25 on both sides in the width direction of the flow path 25. Furthermore, the tip of the flow path 25 is sealed by a flow path sealing seal section 25c formed from the seal section between the body members 21.

[0046] When opening the packaging bag 20, the body member 21 can be torn across the flow path 25 and the flow path forming seal portions 25a and 25b to open the flow path 25. For example, an opening start portion 26, such as a notch, may be formed at least one location in the flow path forming seal portions 25a, 25b or the flow path sealing seal portion 25c.

[0047] To facilitate tearing from the opening start portion 26, it is preferable to provide a cut that penetrates the body member 21 or a half-cut portion (not shown in Figure 2) that does not penetrate the body member 21 at an appropriate position and shape. For example, the opening start portion 26 may be provided at the top of the opening portion 24, and a cut may be provided in the flow path forming seal portion 25a to form a tab. The half-cut portion 11 shown in Figure 1 is formed at an appropriate position on the flow path 25. The half-cut portion 11 may traverse the flow path 25 between the flow path forming seal portions 25a and 25b.

[0048] The illustrated packaging bag 20 has a storage section 27 for containing contents C and a bottom section 28 that can stand on its own by opening the bottom member 22. The storage section 27 and the opening section 24 are integrally formed from the body member 21. When the packaging bag 20 is made to stand on its own with the bottom section 28 facing downwards, the storage section 27 is positioned on the bottom section 28, and the opening section 24 is positioned above the storage section 27.

[0049] Specific examples of packaging bags are not limited to the illustrated packaging bag 20, but include three-side sealed bags, four-side sealed bags, pillow bags, gusset bags, standing pouches, etc. If the laminate is a flexible laminated film, a flexible packaging bag can be formed. Because it is easy to refill and dispose of, it can be suitably used as a refillable packaging bag such as a refill pouch. The packaging bag may have a filling opening, a pouring spout, etc. The pouring spout may be formed in a shape that protrudes thinly from the top or corner of the packaging bag.

[0050] The dimensions of the packaging bag are not particularly limited, but for example, for use as a refillable container, the height in the vertical direction is about 100-500 mm, the width in the horizontal direction is about 70-300 mm, and the filling volume is about 100 cm. 3 ~5000cm 3 The degree can be mentioned. The state of the contents can be fluids such as liquids, powders, and granules. The type of contents is not particularly limited, but can be detergents, chemicals, cosmetics, pharmaceuticals, beverages, seasonings, inks, paints, fuels, etc.

[0051] Although the present invention has been described above based on preferred embodiments, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention. [Examples]

[0052] The present invention will be specifically described below with reference to examples.

[0053] <Materials used> MDOPE1: MD-oriented uniaxially oriented film co-extruded from HDPE / adhesive resin / EVOH / adhesive resin / HDPE (total thickness 25 μm, of which HDPE is 16 μm) MDOPE2: HDPE uniaxially oriented film in the MD direction BOPE: Biaxially oriented film with LLDPE ratio AC: Two-component urethane anchor coat AD: Two-component urethane adhesive LLDPE: Extruded resin layer of LLDPE Sealant 1: Co-extruded film of LLDPE / HDPE / LLDPE Sealant 2: LLDPE film

[0054] (Example 1) A first laminate having a base layer and an intermediate layer was fabricated by bonding MDOPE1 (thickness 25 μm) and BOPE (thickness 25 μm) with dry lamination (using AD). An anchor coat layer (using AC) was applied to the intermediate layer side of the first laminate and dried. An extruded resin layer (LLDPE, thickness 20 μm) was then laminated on top of the anchor coat layer and sandwich laminated with sealant 1 (thickness 70 μm).

[0055] In Example 1, the thickness of the anchor coat layer (AC thickness) was set to 10 nm. A laser was irradiated from the substrate layer side of the laminated structure to form a half-cut section, and the test laminate of Example 1 was fabricated. In the test laminate, the half-cut section was formed in a straight line at a 45° angle with respect to the MD direction.

[0056] (Comparative Example 1) A test laminate of Comparative Example 1 was prepared in the same manner as in Example 1, except that the first laminate and sealant 1 were sandwich-laminated with an extruded resin layer without applying an anchor coat. In Table 1, the AC thickness is shown as 0 nm.

[0057] (Examples 2-5 and Comparative Examples 2-3) Test laminates for Examples 2-5 and Comparative Examples 2-3 were prepared in the same manner as in Example 1, except that the AC thickness was set to 600 nm in Example 2, 1 μm in Example 3, 1.6 μm in Example 4, 2.3 μm in Example 5, 3.3 μm in Comparative Example 2, and 4.9 μm in Comparative Example 3.

[0058] (Example 6) The test laminate of Example 6 was prepared in the same manner as in Example 1, except that MDOPE2 was used instead of MDOPE1 and sealant 2 was used instead of sealant 1.

[0059] (severe) The tearability of the test laminate was evaluated subjectively according to the following criteria. Excellent (○): Cuts easily without applying force. • Good (△): Can be cut with a little force. • No (×): It won't cut unless you apply a lot of force.

[0060] (Laser reactivity) The laser reactivity when forming half-cut sections in the test laminate was evaluated by observing the cross-section of the laminate after laser processing, according to the following criteria. • Excellent (○): The laser does not react to the anchor coat layer, and a half-cut portion is formed without reaching the anchor coat layer. • No (×): The laser reacts with the anchor coat layer, and a half-cut section is formed before it reaches the anchor coat layer.

[0061] (Opening strength) The opening strength of the test laminate was evaluated by creating a packaging bag as shown in Figure 1 using two test laminates, and by gripping one side of the half-cut section (one side straddling the half-cut section) with the chucks of a tensile testing machine and pulling at a speed of 500 mm / min until the half-cut section was opened, so as to open the flow channel along the half-cut section formed in a straight line at a 45° angle on both sides of the flow channel 25, and measuring the maximum load (N) until the half-cut section was opened. The evaluation was then performed according to the following criteria. • Excellent (○): The opening strength is 20N or less. • Good (△): The opening strength is greater than 20N but less than 25N. • No (×): The opening strength is 25N or higher.

[0062] (Environmentally compliant) The environmental performance of the test laminate was evaluated according to the following criteria, based on the polyethylene content (weight %). • Excellent (○): Polyethylene content is greater than 91% by weight. • Good (△): Polyethylene content is more than 90% by weight and 91% or less by weight. • No (×): The polyethylene content is 90% by weight or less.

[0063] [Table 1]

[0064] As shown in Table 1, it was confirmed that when the anchor coat layer thickness (AC thickness) is between 10 nm and 2.5 μm, excellent tearability is achieved, and the amount of dissimilar materials other than polyethylene resin can be reduced. [Explanation of Symbols]

[0065] C...Contents, 10...Laminate, 11...Half-cut section, 12...Base layer, 13...Extruded resin layer, 14...Sealant layer, 15...Anchor coat layer, 16...Laser absorption layer, 17...Intermediate layer, 20...Packaging bag, 21...Body member, 21a, 21b...Body seal section, 22...Bottom member, 22a...Fold line, 22b...Bottom seal section, 23...Top seal section, 24...Opening section, 25...Flow channel, 25a, 25b...Flow channel forming seal section, 25c...Flow channel sealing seal section, 26...Opening start section, 27...Storage section, 28...Bottom section.

Claims

1. A laminate in which a half-cut portion is formed, The laminate comprises, in this order, a base layer formed from polyethylene resin, an extruded resin layer formed from polyethylene resin, and a sealant layer formed from polyethylene resin. The aforementioned half-cut portion is formed by removing at least a portion of the substrate layer in the thickness direction by laser irradiation without penetrating the laminate in the thickness direction. An anchor coat layer is provided on the surface of the extruded resin layer facing the substrate layer, with a thickness of 10 nm to 2.5 μm. The laminate is characterized in that the half-cut portion does not reach the anchor coat layer, the extruded resin layer, and the sealant layer.

2. The laminate according to claim 1, characterized in that the base layer includes an stretched polyethylene resin layer.

3. The laminate according to claim 1, wherein the laminate comprises an intermediate layer made of polyethylene resin between the base material layer and the anchor coat layer, and the half-cut portion is formed to a part of the thickness direction of the intermediate layer.

4. The laminate according to claim 3, characterized in that the laminate comprises at least one selected from the group consisting of an adhesive layer and a printed layer between the base material layer and the intermediate layer.

5. The laminate according to claim 3, characterized in that the intermediate layer includes an stretched polyethylene resin layer.

6. A packaging bag having a half-cut portion formed in the opening portion, characterized in that the laminate having the half-cut portion in the opening portion is made of the laminate described in any one of claims 1 to 5.

7. The packaging bag according to claim 6, characterized in that it is a refill pouch.

8. The packaging bag according to claim 6, characterized in that it is a standing pouch.

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