Laminate for lid material, lid material, and container

Abstract

To provide a laminate for a lid material, and a lid material or the like, which have low environmental impact and easy peelability to enable easy peeling without causing damage or the like to a container body during peeling even when the container body has low strength.SOLUTION: A laminate for a lid material is provided with a paper base material and a heat seal layer. The heat seal layer has a dry weight of 1 g / m2 to 10 g / m2 inclusive. When heat seal surfaces of the laminate are sealed under conditions of 150°C (single-side heating), heat plate width of 10 mm, for 2 seconds, at 1.5 kgf / cm2, the peel strength measured the method described in JIS Z 0238 is 4.0 N / 15 mm or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a laminate for a lid material, a lid material, and a container provided with the lid material.

Background Art

[0002] In the field of food packaging, as a method of packaging cooked frozen foods, instant noodles, yogurt, etc., a method is known in which food is placed in a formed container body, a lid material having a heat-sealing layer is heat-bonded, and the container opening is sealed. As a lid material used for such packaging, from the viewpoints of simplicity and hygiene, it is required to have so-called easy-peelability, which can be easily opened by hand, does not cause breakage of the container body, and can be opened cleanly.

[0003] Moreover, recently, reduction of the usage amount of petroleum-derived plastics has been demanded, and the demand for packaging materials using paper materials as materials that can reduce the environmental load has been increasing, and it has been demanded to use paper materials also for food container bodies and their lid materials.

[0004] As a container in which a lid material is heat-sealed to a container body using a paper material, for example, Patent Document 1 discloses a container in which a film composed of polyethylene terephthalate and linear low-density polyethylene is heat-sealed to a pulp-molded container body.

[0005] Further, as a lid material having easy-peelability and using a paper base material, for example, Patent Document 2 discloses a lid material composed of a laminate in which a biaxially stretched polybutylene terephthalate film and an easy-peelable film are sequentially laminated on a paper base material.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

[0007] As mentioned above, in order to reduce the environmental impact, there is a demand for laminates that use a paper base material and can be used as lid materials with reduced plastic usage. Similarly, there is a demand for container bodies for holding food that are made of paper, such as pulp molds and paper cups. However, because paper container bodies generally have lower strength than plastic container bodies, even when a lid material using an easy-peel film is used, there is a problem that the heat seal strength is excessive and the container body breaks when opened. Breaking the container body is undesirable because there is a risk that paper fragments, etc., generated from the broken area may be mixed into food, etc.

[0008] In addition, in order to reduce breakage of the container body, one method is to reinforce the strength of the container body by, for example, laminating a resin film inside the container body, but this is not desirable from the perspective of environmental impact because the proportion of resin in the container body becomes too large.

[0009] The present invention aims to provide a laminate and a lid material that have a low environmental impact, can be opened cleanly without causing tearing of the container body or lid, whether the container body is made of a plastic material or a paper material, and have easy-peel properties and can be used as a lid material. [Means for solving the problem]

[0010] A first aspect of the present invention is a laminate for a lid material, A paper substrate; Heat seal layer At least The dry weight of the heat seal layer is 1 g / m 2 More than 10g / m 2 is as follows: Heat seal surfaces of laminated body are heated to 150℃ (one side heating), hot plate width 10mm, 2 seconds, 1.5kgf / cm 2It is a laminate for a lid material that is sealed under the following conditions and has a peel strength of 4.0 N / 15 mm or less as measured by the method described in JIS Z 0238 (1998).

[0011] It is preferable that the heat-sealing layer mainly comprises a thermoplastic resin.

[0012] It is preferable that the thermoplastic resin is an acrylic resin.

[0013] It is preferable that the thermoplastic resin has a melting point or glass transition point of 110°C or higher.

[0014] It is preferable that the heat-sealing layer contains a wax component.

[0015] It is preferable that the heat-sealing layer is a coating layer or a printing layer.

[0016] The heat-sealing layer may be a discontinuous layer that occupies only a part of the surface of the laminate.

[0017] The lid material is a lid material for a container body having an opening, It is preferable that the container body is made of paper or pulp mold.

[0018] It is preferable that the container body does not contain a thermoplastic resin film.

[0019] It is preferable that at least one intermediate layer is included between the paper base material and the heat-sealing layer.

[0020] A second aspect of the present invention is a lid material comprising the laminate of the present invention.

[0021] A third aspect of the present invention is a container comprising the lid material of the present invention and a container body having an opening, wherein the lid material is heat-sealed to the container body, and the opening is sealed.

Advantages of the Invention

[0022] The laminate of the present invention can be thermally adhered to the container body through a heat-sealing layer. Therefore, the laminate of the present invention can be suitably used as a lid material for containers.

[0023] The laminate of the present invention is paper-based and environmentally friendly.

[0024] The laminate of the present invention has easy peelability. Therefore, even if the container body is made of a plastic material or a paper material, the container body and the lid can be cleanly opened without causing breakage.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0026] The laminate of the present invention a paper base material, a heat-sealing layer and at least includes the dry weight of the heat-sealing layer is 1 g / m 2 or more and 10 g / m 2 or less, the heat-sealing surfaces of the laminate are sealed under the conditions of 150 °C (one-sided heating), a hot plate width of 10 mm, 2 seconds, and 1.5 kgf / cm 2 and the peel strength measured by the method described in JIS Z 0238 (1998) is 4.0 N / 15 mm or less, and it is a laminate for a lid material.

[0027] [Paper base material] The laminate of the present invention includes a paper base material. There may be a plurality of paper base materials, but in order to suppress the overall layer thickness, it is preferable that there is one paper base material.

[0028] The paper base material is a base material made of paper and has a sheet shape. The paper base material forms the base material layer of the laminate of the present invention.

[0029] The basis weight of the paper base material (measurement method: JIS P 8124

[2011] ) is 120 g / m 2 The following is preferable, 110 g / m 2 The following is more preferable, 100 g / m 2 The following is even more preferable. By suppressing the basis weight of the paper base material, the thickness of the paper base material can be suppressed. And thereby, the thermal conductivity of the paper base material can be increased, and thus, the heat seal suitability of the laminate of the present invention can also be increased.

[0030] On the other hand, the basis weight of the paper base material is 30 g / m 2 The above is preferable, 40 g / m 2 The above is more preferable, 50 g / m 2 The above is even more preferable. By setting the basis weight of the paper base material to a certain level or more, the amount of plastic used in the laminate can be reduced, and thus the environmental load can be reduced. Therefore, the basis weight of the paper base material is 30 g / m 2 ~120 g / m 2 The following is preferable, 40 g / m 2 ~110 g / m 2 The following is more preferable, 50 g / m 2 ~100 g / m 2 The following is even more preferable.

[0031] The thickness of the paper base material (measurement method: JIS P 8118

[2014] ) is preferably 160 μm or less, more preferably 140 μm or less, and even more preferably 120 μm or less. Also, the thickness of the paper base material is preferably 30 μm or more, more preferably 40 μm or more, and even more preferably 50 μm or more. Therefore, the thickness of the paper base material is preferably 30 μm to 160 μm, more preferably 40 μm to 140 μm, and even more preferably 50 μm to 120 μm.

[0032] The raw materials for the paper base material are not particularly limited, and examples include wood pulp such as softwood pulp and hardwood pulp. The wood pulp can be chemical pulp such as bleached pulp or unbleached pulp, groundwood pulp, thermomechanical pulp, chemithermomechanical pulp, etc., and recycled pulp. In addition, a small amount of non-wood pulp such as hemp, bamboo, straw, kenaf, paulownia, paper mulberry, cotton, etc., and non-cellulose fibers such as rayon fiber, polyethylene fiber, cotton fiber, etc. may be mixed with the wood pulp.

[0033] The type of the paper base material is not particularly limited, and various types of paper can be used. Examples include high-quality paper, medium-quality paper, one-sided coated paper, unbleached kraft paper, bleached kraft paper, etc.

[0034] [Heat-sealing layer] The laminate of the present invention includes a heat-sealing layer. The heat-sealing layer may be one layer or a plurality of layers.

[0035] The dry weight of the heat-sealing layer is 1 g / m 2 to 10 g / m 2 or less. Also, the dry weight of the heat-sealing layer is more preferably 2 g / m 2 to 9 g / m 2 or less, and even more preferably 3 g / m 2 to 8 g / m 2 or less. By setting the weight of the heat-sealing layer within this range, a laminate having easy peelability can be obtained while maintaining the required heat-sealing strength.

[0036] The heat-sealing layer seals the heat-sealing surfaces of the laminate at 150 °C (one-sided heating), a hot plate width of 10 mm, for 2 seconds, and a pressure of 1.5 kgf / cm 2 under the conditions, and the peel strength measured by the method described in JIS Z 0238 (1998) is 4.0 N / 15 mm or less, more preferably 3.8 N / 15 mm or less, and even more preferably 3.6 N / 15 mm or less. Thereby, the laminate of the present invention can exhibit easy peelability.

[0037] On the other hand, the peel strength is preferably 1.5 N / 15 mm or more, more preferably 2.0 N / 15 mm or more, and even more preferably 2.5 N / 15 mm or more in order to protect the contents during transportation etc.

[0038] The heat-sealing layer is mainly composed of a thermoplastic resin. The main component means that the weight fraction of the component is 50% or more. The type of the thermoplastic resin is not particularly limited, and examples thereof include polyolefins (such as polyethylene and polypropylene), ethylene / vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, acrylic polymers such as acrylate esters, polyacrylonitrile, acrylonitrile / butadiene copolymer, ABS resin, polyurethane, polyvinylidene fluoride, fluororesin, polycarbonate, polyamide, polyacetal, polyphenylene oxide, polyesters (such as polyethylene terephthalate and polybutylene terephthalate), polyphenylene sulfide, polyimide, polysulfone, polyethersulfone, polyarylate, olefin / unsaturated carboxylic acid copolymer, and the like.

[0039] In terms of the strength after heat-sealing etc., the type of the thermoplastic resin is preferably mainly composed of an acrylic resin. As the acrylic resin, an acrylate ester copolymer, polyacrylonitrile, acrylonitrile / butadiene copolymer, and ABS resin are preferable, and a styrene acrylate ester copolymer is more preferable.

[0040] The melting point or glass transition point of the resin which is the main component of the heat-sealing layer is preferably 110°C or more, more preferably 115°C or more, and even more preferably 120°C or more. By setting the melting point or glass transition point to this temperature, the heat resistance of the lid material can be enhanced, and it can be suitably used without causing denaturation etc. of the heat-sealing layer even when heating the food together with the container in a microwave oven in a food container.

[0041] On the other hand, from the perspective of productivity, the melting point or glass transition point of the resin, which is the main component of the heat-sealing layer, is preferably 180°C or lower, more preferably 175°C or lower, and even more preferably 170°C or lower.

[0042] The peel strength after heat-sealing can be adjusted by adjusting the dry weight of the heat-sealing layer. However, for further adjustment of the peel strength, a wax component can be added to the heat-sealing layer. The wax component is not particularly limited, and examples thereof include polyethylene, polypropylene, poly-α-olefin, silicone, carnauba wax, candelilla wax, beeswax, wood wax, rice wax, and the like. By adding the wax component, the peel strength of the heat-sealing layer can be reduced, and a heat-sealing layer with stable peel strength can be provided even in a coating machine that is difficult to coat with a thin film such as a blade coater or an air knife coater.

[0043] The addition amount of the wax component is not particularly limited, but when the entire heat-sealing layer is 100 parts by weight, it is preferably 0.1 part by weight or more and 10.0 parts by weight or less, more preferably 0.2 part by weight or more and 7.5 parts by weight or less, and even more preferably 0.5 part by weight or more and 5.0 parts by weight or less.

[0044] The heat-sealing layer is preferably a coating layer or a printing layer obtained by applying and drying a dispersion of a thermoplastic resin on a paper substrate, rather than a layer formed by lamination or extrusion lamination of a molten resin. From the perspective of further reducing the environmental load, the coating layer is preferably an aqueous coating layer obtained from an aqueous dispersion.

[0045] It is difficult to form a layer with a thickness below a certain level for a layer provided by lamination or extrusion of a molten resin. Therefore, the peel strength after heat-sealing tends to be excessively large. However, a heat-sealing layer formed by coating or printing is easily thinned, and the peel strength after heat-sealing is less likely to become excessively large. In addition, by thinning the heat-sealing layer, the amount of plastic used can be further reduced, and the environmental load can be further reduced.

[0046] The heat-sealing layer may be a discontinuous layer that occupies only a part of the surface of the laminate. That is, the heat-sealing layer may be present only in a part of the surface of the laminate. By making the heat-sealing layer a discontinuous layer, it becomes easier to adjust the peel strength, and the environmental load can be further reduced.

[0047] When the heat-sealing layer is a discontinuous layer that occupies only a part of the surface of the laminate, for example, the heat-sealing layer can be provided only on the part of the surface of the laminate that is adhered to the container body during use, or the heat-sealing layer can be provided on the surface of the laminate in a pattern such as dots or stripes.

[0048] [Intermediate layer] The laminate of the present invention preferably includes an intermediate layer between the paper base material and the heat-sealing layer. The material of the intermediate layer is not particularly limited and can be appropriately selected according to the use and required functions, such as a thermoplastic resin film or a metal foil. The intermediate layer may be present on the entire surface between the paper base material and the heat-sealing layer, or may be present in a part.

[0049] The intermediate layer is preferably a thermoplastic resin film. The type of thermoplastic resin is not particularly limited, and examples thereof include polyolefin (such as polyethylene and polypropylene), polyester, nylon, polyvinyl alcohol, ethylene-vinyl alcohol copolymer resin, and polyacrylonitrile. By using a thermoplastic resin film, the oil resistance and mechanical strength of the laminate can be enhanced.

[0050] The thermoplastic resin film is preferably a film containing nylon. By using a film containing nylon, the mechanical strength of the laminate can be further enhanced. The nylon film may be an unstretched film or a stretched film.

[0051] Regarding the thickness of the nylon film, 10 μm or more is preferable, 12 μm or more is more preferable, and 15 μm or more is even more preferable. By setting the thickness of the nylon film to a certain level or more, the mechanical strength of the laminate can be increased.

[0052] Regarding the thickness of the nylon film, 50 μm or less is preferable, 40 μm or less is more preferable, and 30 μm or less is even more preferable. By suppressing the thickness of the nylon film, the amount of plastic used can be reduced, and the environmental load can be decreased.

[0053] [Manufacturing Method] The laminate of the present invention can be manufactured by a method including a step of coating a dispersion of a thermoplastic resin on at least one surface of a paper substrate, and a step of drying the paper substrate after the coating to form a heat-seal layer.

[0054] Regarding the type of the dispersion medium of the dispersion of the thermoplastic resin, water is preferable from the viewpoint of reducing the environmental load, but organic solvents such as ethanol, isopropyl alcohol, methyl ethyl ketone, and toluene may be included.

[0055] The compounding amount of the thermoplastic resin in the dispersion is not particularly limited, but 3% by weight or more is preferable, 5% by weight or more is more preferable, and 10% by weight or more is even more preferable. On the other hand, from the viewpoint of coatability, 80% by weight or less is preferable, 70% by weight or less is more preferable, and 60% by weight or less is even more preferable. Therefore, the amount of the thermoplastic resin in the dispersion is preferably 3% by weight to 80% by weight, more preferably 5% by weight to 70% by weight, and even more preferably 10% by weight to 60% by weight.

[0056] The step of coating the dispersion liquid on the paper substrate can be carried out using known equipment. Such known coating equipment includes blade coaters, bar coaters, air knife coaters, slit die coaters, gravure coaters, micro gravure coaters, roll coaters, size presses, gate roll coaters, sim sizeers, and the like. Further, the dispersion liquid may be coated entirely or partially on the paper substrate by gravure printing, offset printing, flexographic printing, or the like.

[0057] The drying step of the paper substrate after coating can also be carried out using known equipment. Such known drying equipment includes hot air dryers, infrared dryers, and the like. The drying temperature and drying time can be appropriately set in consideration of the type of thermoplastic resin, the type of dispersion medium of the dispersion liquid, the blending amount of thermoplastic resin particles in the dispersion liquid, and the like.

[0058] In the production of the laminate of the present invention, an intermediate layer may be laminated on at least one surface of the paper substrate, and a heat seal layer may be provided on the intermediate layer. As a method of laminating the intermediate layer, known methods such as dry lamination method, wet lamination method, solventless lamination method, and extrusion lamination method can be used. For example, a known dry laminating agent can be applied as an adhesive layer to laminate the intermediate layer to the paper substrate. The coating amount of the dry laminating agent is not particularly limited, but is preferably 1 g / m 2 ~8 g / m 2 is preferable, and 2~6 g / m 2 is more preferable.

[0059] [Use] The laminate of the present invention can be suitably used as a lid material that is heat-sealed to a container body. In particular, it is preferably used as a lid material for food containers.

[0060] The present invention also relates to a lid material comprising the laminate, and a container provided with the lid material.

[0061] The laminate and the lid material of the present invention have a heat-sealing layer, and the opening of the container can be sealed by thermocompression bonding to a part such as the flange of the container body.

[0062] The container of the present invention is a container including the lid material of the present invention and a container body having an opening, wherein the lid material is heat-sealed to the container body, and the opening is sealed.

[0063] The container of the present invention can be manufactured by heat-sealing the laminate or the lid material of the present invention to the container body having an opening to seal the opening.

[0064] For the container body, known materials such as paper and plastic can be used. However, from the viewpoint of reducing the environmental load, it is preferable to use paper materials such as paper cups and pulp molds, and it is more preferable not to include a film of a thermoplastic resin.

[0065] FIG. 1 is a cross-sectional view showing an example of the laminate of the present invention and an example of a container using the laminate as a lid material, and the container corresponds to the container of the present invention.

[0066] In FIG. 1, 4 is a lid material made of the laminate of the present invention, and 5 is a container body.

[0067] The lid material 4 includes a paper base material 1, an intermediate layer 2, and a heat-sealing layer 3 in this order, and is adhered to the flange portion around the opening of the container body 5 via the heat-sealing layer 3 to seal the opening.

[0068] FIG. 2 is an enlarged cross-sectional view of an example of the laminate of the present invention shown in FIG. 1. In FIG. 2, 6 is the interface between the intermediate layer and the heat-sealing layer, and 7 is the interface between the heat-sealing layer and the container body.

[0069] When peeling off the lid material having a heat-sealing layer and an intermediate layer from the container body, if the breaking strength of the intermediate layer is greater than that of the container body, any of the following patterns may occur: A: peeling at the interface (6) between the intermediate layer and the heat-sealing layer, B: cohesive failure of the heat-sealing layer (3), C: peeling at the interface (7) between the heat-sealing layer and the container body, D: breakage of the container body (5). Among these, for C: peeling at the interface (7) between the heat-sealing layer and the container body and D: breakage of the container body (5), they can vary depending on the heat-sealing conditions with the container body, the material of the container body, the manufacturing method, etc. Note that when using a container body with low strength, D: breakage of the container body (5), that is, breakage of the container, is likely to occur.

[0070] On the other hand, according to the measurement method of heat-sealing the heat-sealing layers of the lid material and examining the peel strength, when the lid material has an intermediate layer, the lower strength of either A: peeling at the interface (6) between the intermediate layer and the heat-sealing layer or B: cohesive failure of the heat-sealing layer (3) can be measured. By adjusting the peel strength measured by the above measurement method within the above range, even when the breaking strength of D: the container body (5) is low, the lid material can be peeled off and used without damaging the container body.

[0071] In the laminate of the present invention shown in FIG. 2, the peel strength measured by the above measurement method is 4.0 N / 15 mm or less. Thus, since the peel strength of the laminate of the present invention is suppressed, good easy-peelability can be exhibited.

Industrial Applicability

[0072] The laminate of the present invention can be suitably used for packaging applications as a laminate for a lid material with reduced environmental impact.

[0073] Also, since the laminate of the present invention has easy-peelability, it can be suitably used without damaging the container body during opening even when used as a lid material for a container body with low strength.

Examples

[0074] [Example 1] Grammage 80 g / m 2 On the non-smooth surface of the bright kraft paper with a grammage of 80 g / m, a heat-sealing layer was formed by applying 6.1 g / m of Heat Seal Niss (manufactured by Daiichi Paint Industry Co., Ltd., Harbil HS-1), which is an acrylic ester copolymer resin, using a bar coater, and a laminate for a lid material was produced. 2

[0075] [Example 2] Grammage 28.3 g / m 2 On the corona-treated surface of a nylon film (manufactured by Unitika Ltd., Emblem ONU-25) with a grammage of 28.3 g / m, a dry laminating agent was applied using a bar coater to form an adhesive layer. As the dry laminating agent, a mixture of 15 parts by weight of TM-250HV, 2 parts by weight of CAT-RT86L-60, and 10 parts by weight of ethyl acetate, all manufactured by Toyo Morton Co., Ltd., was used. The application amount of the dry laminating agent was about 4 g / m 2 . Next, on this adhesive layer, the non-smooth surface of bright kraft paper with a grammage of 80 g / m as a paper base material was laminated and aged at 40°C. Then, on the surface of the nylon film that was not laminated with the bright kraft paper, Heat Seal Niss (manufactured by Daiichi Paint Industry Co., Ltd., Harbil HS-1) was applied at an application amount of 6.2 g / m 2 using a bar coater to form a heat-sealing layer, and a laminate for a lid material was produced. 2

[0076] [Example 3] A laminate for a lid material was produced in the same manner as in Example 2, except that the application amount of Heat Seal Niss (manufactured by Daiichi Paint Industry Co., Ltd., Harbil HS-1) was 9.4 g / m 2 .

[0077] [Example 4] As the heat-sealing layer, a mixture of 2 parts by weight of wax (manufactured by Mitsui Chemicals, Inc., Chem Pearl W-100) and 100 parts by weight of Heat Seal Niss (manufactured by Daiichi Paint Industry Co., Ltd., Harbil HS-1) was applied at an application amount of 6.2 g / m 2 . A laminate for a lid material was produced in the same manner as in Example 2.

[0078] [Comparative Example 1] As a heat-sealing layer, a laminate for a lid material was produced in the same manner as in Example 2, except that an easy-peel film (manufactured by DIC Corporation, E7800PET) was dry-laminated.

[0079] [Comparative Example 2] As a heat-sealing layer, a laminate for a lid material was produced in the same manner as in Example 2, except that the coating amount of a heat-sealing varnish (manufactured by Daiichi Paint Industry Co., Ltd., Harbil HS-1) was 12.2 g / m 2 The above.

[0080] [Evaluation Method] (Dry Weight of Heat-Sealing Layer) In accordance with the method described in JIS P 8124, the basis weight of the paper substrate or the laminate of the paper substrate and other layers before and after the formation of the heat-sealing layer was measured, and the difference was taken as the dry weight of the heat-sealing layer per unit area. The results are shown in Table 1.

[0081] (Heat-Sealing Strength) After conditioning the laminate test piece in accordance with the method described in JIS P 8111 (1998), the heat-sealing surfaces of the laminate were sealed at 150 °C (one-sided heating), for 2 seconds, under the condition of 1.5 kgf / cm 2 The heat-sealing hot plate had a sealing width of 10 mm and a flat sealing surface shape. Further, the peel strength of the test piece after heat-sealing was measured in accordance with the method described in JIS Z 0238 (1998). The results are shown in Table 1.

[0082] (Melting Point or Glass Transition Point) The melting point or glass transition point of the sample obtained by peeling or scraping off the resin of the heat-sealing layer from the laminate was measured by a method using a differential thermal analyzer defined in JIS K 7121 (2012). The results are shown in Table 1.

[0083] (Peelability from Container Body) A test piece with a width of 15 mm and a length of 50 mm was cut out from the laminate so that the MD direction became the long side. On the other hand, a pulp mold food container was prepared as the container body, and a test piece with a bottom width of 15 mm and a length of 50 mm of the container body was cut out. Then, the inner side of the container body and the heat-sealing layer of the laminate were overlapped facing each other and heat-sealed. The sealing conditions were 150 °C (one-sided heating from the laminate side for the lid material), a hot plate width of 10 mm, 2 seconds, and 1.5 kgf / cm 2 was used. Then, the end of the non-bonded part of the laminate was grasped, folded back 180 degrees as shown in Figure 3, and pulled at a speed of 50 mm / min in the direction parallel to the heat-sealed surface to peel it from the container body. The surface of the container body after peeling was observed, and those without fluffing or tearing were marked as ○, those with fluffing but no tearing were marked as △, and those with tearing were marked as ×. The results are shown in Table 1.

[0084]

Table 1

[0085] From the results in Table 1, the laminates (lid materials) of Examples 1 to 4 had good peelability from the container body and no tearing of the container body was observed. In particular, in Example 4, there was no fluffing on the container body after peeling. On the other hand, the laminates (lid materials) of Comparative Example 1 and Comparative Example 2 had poor peelability from the container body, and there was tearing of the container body during peeling.

Explanation of symbols

[0086] 1 Paper base material 2 Intermediate layer 3 Heat-sealing layer 4 Lid material 5 Container body 6 Interface between the intermediate layer and the heat-sealing layer 7 Interface between the heat-sealing layer and the container body

Claims

1. A laminate for a lid material, comprising: a paper base material, a heat-sealing layer and at least including The dry weight of the heat-sealing layer is 1 g / m ２ or more and 10 g / m ２ or less, and The heat-sealed surfaces of the laminate were heated at 150°C (one side heating), with a hot plate width of 10 mm, for 2 seconds, and at 1.5 kgf / cm ２ and a peel strength measured by the method described in JIS Z 0238 (1998) of 4.0 N / 15 mm or less.

2. The laminate for a lid material according to Claim 1, wherein the heat-sealing layer is mainly composed of a thermoplastic resin.

3. The laminate for a lid material according to Claim 2, wherein the thermoplastic resin is an acrylic resin.

4. The laminate for a lid material according to Claim 2 or 3, wherein the thermoplastic resin has a melting point or glass transition point of 110°C or higher.

5. The laminate for a lid material according to any one of Claims 1 to 3, wherein the heat-sealing layer contains a wax component.

6. The laminate for a lid material according to any one of Claims 1 to 3, wherein the heat-sealing layer is a coating layer or a printing layer.

7. The laminate for a lid material according to Claim 6, wherein the heat-sealing layer is a discontinuous layer that occupies only a part of the surface of the laminate.

8. The lid material is a lid material for a container body having an opening, The laminate for a lid material according to any one of Claims 1 to 3, wherein the container body is made of paper or pulp mold.

9. The laminate for a lid material according to Claim 8, wherein the container body does not contain a thermoplastic resin film.

10. The laminate for a lid material according to any one of Claims 1 to 3, including at least one intermediate layer between the paper base material and the heat-sealing layer.

11. A lid material made of the laminate according to any one of Claims 1 to 3.

12. A container comprising the lid material according to Claim 11 and a container body having an opening wherein the lid material is heat-sealed to the container body, and the opening is sealed. ​

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