Laminated and rolled materials

Abstract

A laminate comprising a paper substrate, a coating layer comprising a polyolefin resin, and a plurality of particles fixed in the coating layer, the particle size being greater than the thickness of the coating layer.

Description

Technical Field

[0001] This disclosure relates to laminates and rolls having a paper substrate and a coating layer comprising a polyolefin resin. Background Technology

[0002] In recent years, due to increased environmental awareness, starting with issues such as marine plastic waste, the opportunity to reduce plastic use has been rising, and the use of paper to replace plastic materials has been studied in various fields. The packaging materials field is one of them, and Patent Document 1 describes packaging paper having at least one heat-sealing layer on at least one side of a paper substrate.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2020 / 152753 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] According to the researchers of this invention, when the packaging paper is rolled into a roll and the resulting product is pulled out in the next process, a phenomenon easily occurs where paper fibers of the paper substrate are drawn into the heat-sealing layer, that is, paper fibers of the paper substrate peel off and adhere to the surface of the heat-sealing layer (hereinafter referred to as "fiber peeling"). This phenomenon leads to poor appearance of the packaging paper and a reduction in heat-sealing strength. The peeling off of a portion of the substrate and its adhesion to the coating layer is a problem that does not occur when using conventional plastic substrates; it can be considered a new problem arising from setting the substrate to paper.

[0008] Fiber delamination is particularly likely to occur when rolled products are exposed to temperatures of 40°C or higher. According to the researchers of this invention, in order to further reduce the plastic ratio in packaging materials, when a heat-sealable layer is formed by coating, if this heat-sealable layer is exposed to temperatures above 40°C in contact with the paper substrate, the adhesion to the paper substrate increases, making fiber delamination more likely. It should be noted that when rolled products are packed into containers for export by ship, temperatures inside the container may reach approximately 60°C depending on the ship's route.

[0009] This disclosure provides laminates and rolls with minimal fiber delamination even after exposure to temperatures of 40°C or higher.

[0010] Methods for solving problems

[0011] One aspect of the laminate disclosed herein comprises a paper substrate, a coating layer containing a polyolefin resin, and a plurality of particles fixed in the coating layer, the particle size of which is larger than the thickness of the coating layer. According to the laminate described above, since the substrate is made of paper, the amount of plastic material used can be reduced. Furthermore, according to the laminate described above, the contact area between the paper substrate and the coating layer is reduced due to the protruding particles, thus suppressing an increase in the adhesion between the coating layer and the paper substrate even when the laminate is overlapped or rolled into a roll. Therefore, even after exposure to temperatures of 40°C or higher, fiber peeling can be suppressed, resulting in the suppression of poor appearance and a decrease in heat-sealing strength. The laminate of this disclosure is useful in applications such as pillowcases, stand-up pouches, and other packaging bags.

[0012] The peel strength of the above-mentioned laminate, measured by the following process, is preferably 0.1 N / 15 mm or less.

[0013] <Determination of peel strength>

[0014] (a1) The process of placing the sample in a constant temperature bath set at 40°C for 3 days under a load of 100 kgf on a sample formed by stacking 5 of the laminates in the same direction.

[0015] (b1) The process of peeling the two laminates together from the sample after the process (a1) above.

[0016] (c1) The procedure of performing a T-type peel test on the two laminates at a peeling speed of 300 mm / min.

[0017] The peel strength measured in the above (c1) process is such that the laminate within the above range is not prone to fiber peeling even after a heat treatment at 40°C. As a result, it is possible to further suppress appearance defects and the reduction in heat seal strength.

[0018] The heat seal strength of the above-mentioned laminate, measured by the following process, is preferably 2.1 N / 15 mm or higher.

[0019] <Determination of heat seal strength>

[0020] (a2) The process of placing the sample in a constant temperature bath set at 40°C for 3 days under a load of 100 kgf on a sample formed by stacking 5 of the laminates in the same direction.

[0021] (b2) The process of peeling the two laminates from the sample after the process (a2) above.

[0022] (c2) A process of heat-sealing the coating layers of the two laminates together under conditions of pressure of 0.2 MPa, temperature of 120°C and time of 1 second.

[0023] (d2) The process of performing a T-type peel test on the sample obtained in the above (c2) process at a peeling speed of 300 mm / min.

[0024] The heat-sealing strength of the laminate measured after the above process is within the above range. Even after a heat treatment process of 40°C, it can sufficiently suppress fiber peeling and has sufficient heat-sealing strength.

[0025] The material of the aforementioned particles is, for example, selected from the group consisting of polyolefins and their partially modified forms, and alkanes. Because the aforementioned material has good compatibility with the coating layer containing the polyolefin resin, it is less likely to reduce the gas barrier properties of the coating layer. The aforementioned laminate may also further include a vapor-deposited layer between the paper substrate and the coating layer.

[0026] The ratio A / B of the mass A of the coating layer to the mass B of the particles is preferably 100 / 20 to 100 / 0.2. When this ratio is 100 / 20 or higher, the coating layer tends to have sufficient heat-sealing strength; on the other hand, when it is 100 / 0.2 or lower, the occurrence of fiber peeling tends to be sufficiently suppressed.

[0027] One aspect of this disclosure is a roll material formed by winding the aforementioned laminate. According to this roll material, even after exposure to temperatures of 40°C or higher, fiber delamination can be suppressed, resulting in the suppression of poor appearance and reduction in heat-sealing strength.

[0028] Invention Effects

[0029] According to this disclosure, laminates and rolls with minimal fiber delamination can be provided even after exposure to temperatures of 40°C or higher. Attached Figure Description

[0030] Figure 1 This is a cross-sectional view schematically representing one embodiment of the laminate of the present disclosure.

[0031] Figure 2 This is a cross-sectional view schematically illustrating other embodiments of the laminate of this disclosure.

[0032] Figure 3 (a) is a schematic cross-sectional view of a specimen housed in a constant temperature bath during the peel strength test and heat seal strength test in this disclosure. Figure 3 (b) is a cross-sectional view schematically representing the state of the peel strength test.

[0033] Figure 4 (a) is a schematic cross-sectional view of a specimen used for determining heat seal strength in this disclosure. Figure 4 (b) is a cross-sectional view schematically representing the state of performing the heat seal strength test.

[0034] Figure 5 This is a cross-sectional view schematically illustrating other embodiments of the laminate of this disclosure. Detailed Implementation

[0035] The embodiments of this disclosure will be described with reference to the accompanying drawings as needed. However, the present invention is not limited to the following embodiments.

[0036] [Layered Body]

[0037] Figure 1 This is a schematic cross-sectional view of the laminate according to this embodiment. The laminate 10 shown in the figure includes a paper substrate 1, a coating layer 2 containing a polyolefin resin, and a plurality of particles 5 fixed in the coating layer 2. The particle size of the particles 5 is larger than the thickness of the coating layer 2. For the coating layer 2, for example, it is formed by applying a coating liquid containing a polyolefin resin, particles 5, and a solvent, and then removing the solvent by heating. One surface of the laminate 10 is composed of the paper substrate 1, and the other surface is composed of the coating layer 2 and the plurality of particles 5 fixed therein.

[0038] According to laminate 10, since the substrate is made of paper, the amount of plastic material used can be reduced compared to laminates with a plastic substrate. Furthermore, according to laminate 10, such as Figure 1 As shown, particles 5 protrude to the surface of coating layer 2, thus reducing the contact area between coating layer 2 and paper substrate 1. Therefore, even when the paper substrate 1 and coating layer 2 are facing each other due to being overlapped by the laminate 10 or rolled into a roll, the increase in the adhesion between coating layer 2 and paper substrate 1 can be suppressed, and fiber peeling can be highly suppressed. The various components of the laminate 10 will be described below.

[0039] (Paper substrate)

[0040] Specific examples of paper that can be used as paper substrate 1 include fully soluble pulp paper, specialty fully soluble pulp paper, coated paper, art paper, cast coated paper, molding paper, kraft paper, and cellophane. The weight per unit area (mass per unit area) of paper substrate 1 is, for example, 10 to 1000 g / m². 2 Packaging paper with high barrier, water, and oil resistance properties, suitable for flexible packaging, has a unit area weight of, for example, 20–500 g / m². 2 It can also be 25-120 g / m 2 Or 30~95g / m 2 To prevent the coating layer 2 containing polyolefin resin from penetrating into the paper substrate 1, a clay coating layer may also be provided on the paper substrate 1. Figure 2 The laminate 20 shown has a clay coating layer 3 sandwiched between the paper substrate 1 and the coating layer 2.

[0041] (Coating layer)

[0042] The coating layer 2, for example, is a heat-sealing layer in the laminate 10 that imparts sealing properties and contains a polyolefin resin. Examples of polyolefin resins include copolymers or modified forms of ethylene, propylene, acrylic acid, methacrylic acid, maleic anhydride, vinyl acetate, styrene, urethane compounds, and fluorinated compounds. From the viewpoint of improving adhesion to the paper substrate 1, a polyolefin resin containing polar functional groups is preferred; from the viewpoints of water resistance, oil resistance, heat sealing properties, and metal adhesion, an ionomer is preferred.

[0043] In this embodiment, the term "ionomer" refers to a general term for synthetic resins obtained by using the cohesive force generated by metal ions to form polymer aggregates. It is a resin obtained by combining acrylic acid or methacrylic acid with ethylene, etc. Specifically, metal salts of ethylene-methacrylic acid copolymers, metal salts of ethylene-acrylic acid copolymers, metal salts of ethylene-carbamate copolymers, and metal salts of ethylene-fluorine polymer copolymers are all referred to as ionomers. The metals forming the salts are, for example, alkali metal ions, alkaline earth metal ions, specifically sodium, potassium, calcium, magnesium, and zinc ions. Ionomers are preferably metal salts of ethylene-acrylic acid copolymers or ethylene-methacrylic acid copolymers, i.e., self-emulsifying emulsions.

[0044] The thickness T of coating layer 2 Figure 1 The thickness T shown is preferably 0.1 to 10 μm, more preferably 1 to 5 μm. The thickness T of the coating layer 2 can be determined by observing the cross-section of the laminate 10 using an optical microscope or SEM. When the thickness of the coating layer 2 is 0.1 μm or more, compared to cases with a thickness of less than 0.1 μm, the coating layer 2 tends to exhibit sufficient heat-sealing strength. On the other hand, when the thickness is 10 μm or less, compared to cases with a thickness of more than 10 μm, there is a tendency to reduce the amount of plastic material (polyolefin resin) used.

[0045] (particle)

[0046] Particle 5 has the following characteristics: multiple particles are fixed in coating layer 2, and their particle size is larger than the thickness of coating layer 2. The particle size of particle 5 can be determined by the Coulter counting method. The particle size R of particle 5 is... Figure 1 The particle size R shown is preferably 0.2 to 12 μm, more preferably 1.2 to 6.5 μm, provided that it is greater than the thickness T of the dried coating layer 2. With a particle size R of 0.2 μm or more, the thickness of the coating layer 2 can also be relatively thick, thus ensuring sufficient heat-sealing properties of the coating layer 2. On the other hand, with a particle size R of 12 μm or less, there is a tendency to suppress, for example, the undesirable situation of particles 5 clogging in the printing plate used for coating.

[0047] The ratio R / T of the particle size R of particle 5 to the thickness T of coating layer 2 is, for example, 1.05 to 2.0, or possibly 1.1 to 1.5 or 1.1 to 1.3. A value of 1.05 or higher tends to suppress fiber peeling, while a value of 2.0 or lower tends to suppress the peeling of particle 5 from coating layer 2. It should be noted that if coating layer 2 contains particles smaller than this thickness T, these particles do not conform to particle 5.

[0048] The material of particle 5 is selected from the group consisting of polyolefins and their partially modified forms, and alkanes. To reduce adhesion to the paper substrate 1, particle 5 preferably has few polar functional groups on its surface. The same polyolefin used in coating layer 2 can also be used as the polyolefin. From the viewpoint of improving the barrier properties of the laminate 10, the material of particle 5 is preferably high-density polyethylene. Particle 5 may contain constituent units of the same monomers as coating layer 2, or it may contain constituent units of monomers different from those in coating layer 2.

[0049] Particle 5 can also be made of synthetic waxes such as polyolefin wax (polyethylene-based, polypropylene-based) or natural waxes such as paraffin wax. Polyolefin wax has a smaller molecular weight and lower viscosity compared to the polyolefin used in coating layer 2, thus further inhibiting fiber peeling.

[0050] The ratio A / B of the mass A of the coating layer 2 to the mass B of the particles 5 is preferably 100 / 20 to 100 / 0.2, more preferably 100 / 20 to 100 / 0.3. When the ratio is 100 / 20 or higher, the coating layer 2 tends to have sufficient heat-sealing strength; on the other hand, when the ratio is 100 / 0.2 or lower, the occurrence of fiber peeling is sufficiently suppressed.

[0051] [Manufacturing method of laminated bodies]

[0052] A coating layer 2 can be formed by coating one side of a paper substrate 1 with a coating liquid containing polyolefin resin, particles 5, and solvent and then drying it. Specific examples of coating apparatus used in forming the coating layer 2 include air knife coating machines, doctor blade coating machines, gravure coating machines, bar knife coating machines, roller coating machines, reverse roller coating machines, bar coating machines, curtain coating machines, die slot coaters, champlex coaters, metering doctor blade sizing press coating machines, short-stay coating machines, spray coating machines, gate roller coating machines, and lip coating machines.

[0053] [Characteristics of laminates]

[0054] The laminate 10 has the following characteristics: even after being exposed to temperatures of 40°C or higher in an overlapped and wound state, it can suppress fiber peeling, thereby suppressing poor appearance and a decrease in heat seal strength. These characteristics can be confirmed by performing a peel strength test or a heat seal strength test.

[0055] (Peel strength test)

[0056] The peel strength of the laminate 10, measured through the following process, is preferably 0.1 N / 15 mm or less, but may also be 0.08 N / 15 mm or less or 0.05 N / 15 mm or less. The lower limit of this value is, for example, 0.01 N / 15 mm.

[0057] <Determination of peel strength>

[0058] (a1) The process of storing the sample S1 in a constant temperature bath set at 40°C for 3 days under a load of 100 kgf on the sample S formed by stacking 5 laminates 10 in the same direction.

[0059] (b1) The process of peeling the two laminates together from the sample S1 after the above (a1) process.

[0060] (c1) The procedure of performing a T-type peel test on the two laminates at a peeling speed of 300 mm / min.

[0061] Figure 3 (a) is a schematic cross-sectional view of the specimen S1. Figure 3 (b) is a cross-sectional view schematically representing the state of performing the above-described (c1) process. For example... Figure 3 As shown in (b), in step (c1), the paper substrate 1 of one laminate 10 of the laminate S2 is peeled off at the interface with the coating layer 2 of the other laminate 10. A peel strength of 0.1 N / 15 mm or less means that even after step (a1), the adhesion of the coating layer 2 to the paper substrate 1 is sufficiently low. As long as the peel strength is 0.1 N / 15 mm or less, fiber peeling can be sufficiently suppressed.

[0062] In step (a1), the temperature of the constant temperature bath can be set to 60°C instead of 40°C. In this case, the peel strength measured in step (c1) is preferably maintained below 0.1 N / 15 mm, or below 0.08 N / 15 mm or 0.03 N / 15 mm. The lower limit of this value is, for example, 0.01 N / 15 mm. A peel strength of 0.1 N / 15 mm or less means that even after a 3-day thermal process at 60°C, the adhesion of the coating layer 2 to the paper substrate 1 is sufficiently low.

[0063] (Heat seal strength test)

[0064] The heat-sealing strength of the laminate 10, measured through the following processes, is preferably 2.1 N / 15 mm or higher, but may also be 2.5 N / 15 mm or higher, or 2.9 N / 15 mm or higher. An upper limit for this value is, for example, 7.0 N / 15 mm.

[0065] <Determination of heat seal strength>

[0066] (a2) The process of placing the sample S1, which is formed by stacking 5 laminates 10 in the same direction, under a load of 100 kgf, in a constant temperature bath set at 40°C for 3 days.

[0067] (b2) The process of peeling the two laminates from the sample S1 after the above (a2) process.

[0068] (c2) A process of heat-sealing the coating layers of the two laminates together under conditions of pressure of 0.2 MPa, temperature of 120°C and time of 1 second.

[0069] (d2) The process of performing a T-type peel test on the sample S3 obtained in the above (c2) process at a peeling speed of 300 mm / min.

[0070] Figure 4 (a) is a schematic cross-sectional view of the specimen S3. The specimen S3 has a heat-sealed portion 8 in which the coating layer 2 of one layer of the stack 10 is fused together with the coating layer 2 of another layer of the stack 10 by heat. Figure 4 (b) is a cross-sectional view schematically representing the state of performing the above-described (d2) process. For example... Figure 4 As shown in (b), in step (d2), the heat-sealed portion 8 of sample S3 is peeled off. A heat-sealing strength of 2.1 N / 15 mm or more means that even after steps (a2) and (b2), the adhesion of paper fibers due to fiber peeling on the surface of coating layer 2 is sufficiently minimal.

[0071] In step (a2) above, the temperature of the constant temperature bath can be set to 60°C instead of 40°C. In this case, the measured heat seal strength is preferably 1.5 N / 15 mm or more, or 1.8 N / 15 mm or more, or 2.4 N / 15 mm or more. The upper limit of this value is, for example, 5.0 N / 15 mm. A heat seal strength of 1.5 N / 15 mm or more means that even after a 3-day heat treatment at 60°C, fiber delamination can be sufficiently suppressed, ensuring sufficient heat seal strength.

[0072] [Roll Material]

[0073] The roll material can also be made by winding the laminate 10. When making the roll material, it can be wound with the paper substrate 1 facing outwards or with the coating layer 2 facing outwards. The particles 5 contained in the laminate 10 can also be deformed due to the winding pressure.

[0074] The embodiments of this disclosure have been described in detail above, but the present invention is not limited to the above embodiments. For example, the laminate of this disclosure may further include layers other than those described above. Figure 5 The laminate 30 shown has a vapor-deposited layer 4 between the clay coating layer 3 and the coating layer 2.

[0075] Examples of vapor-deposited layer 4 include metal foil, inorganic oxide, or metal vapor-deposited layer. For example, aluminum foil can be used as a metal foil. Examples of inorganic oxides include aluminum oxide, silicon oxide, magnesium oxide, and tin oxide. Examples of metals include aluminum. Vapor-deposited layer 4 can be formed, for example, by physical vapor deposition, chemical vapor deposition, or the like.

[0076] The water vapor permeability of the laminate 30 is, for example, 5 g / m³. 2 For days or less, it can also be 2.5 / m. 2 • Less than 2.1g / m² 2 • Days or less. The oxygen permeability of the laminate 20 is, for example, 1 cc / m³. 2 For amounts below atm / day, 0.5cc / m is also acceptable. 2 • atm • day or less or 0.2cc / m 2 •atm·day and below. By including the vapor-deposited layer 4 in the laminate 30, it becomes easier to protect the contents from deterioration caused by water vapor or oxygen, thus maintaining quality over a long period.

[0077] The laminate disclosed herein may, for example, further include a printing layer (not shown) on the side of the paper substrate 1 opposite to the coating layer 2. From the viewpoint of preventing the printing layer from discoloring or producing an odor upon remelting, it is preferable to use chlorine-free inks when a printing layer is provided. Furthermore, from an environmental perspective, it is preferable to use biomass materials for the compounds contained in the printing ink.

[0078] Example

[0079] The present disclosure will now be described in more detail based on the embodiments, but the present invention is not limited to the following embodiments.

[0080] (Example 1)

[0081] Use the following materials to create the laminate.

[0082] • Paper substrate: Clay-coated paper (weight per unit area: 55g / m²) 2 Thickness: 50μm

[0083] • Coating layer: Aqueous polyolefin dispersion (CHEMIPEARL S100, manufactured by Mitsui Chemicals Co., Ltd.)

[0084] • Particles: Polyethylene particles (CHEMIPEARL W300, manufactured by Mitsui Chemicals, average particle size: 3μm)

[0085] By mixing CHEMIPEARL S100 and CHEMIPEARL W300 in a 100 / 2 ratio (solids component ratio) and coating the mixture onto clay-coated paper to achieve a dried thickness of 2.5 μm, the following was obtained: Figure 2 The structure shown is a stacked body.

[0086] (Example 2)

[0087] Except for the use of the following materials in the coating layer, the laminate of Example 2 is obtained by following the same steps as in Example 1.

[0088] • Coating layer: Ethylene-vinyl acetate dispersion (CHEMIPEARL V200, manufactured by Mitsui Chemicals Co., Ltd.)

[0089] (Example 3)

[0090] Except that CHEMIPEARL S100 and CHEMIPEARL W300 were combined in a solids ratio of 100 / 0.3 and coated onto clay-coated paper, the laminate of Example 3 was obtained by following the same steps as in Example 1.

[0091] (Example 4)

[0092] Except that CHEMIPEARL S100 and CHEMIPEARL W300 were combined in a solids ratio of 100 / 1.5 and coated onto clay-coated paper, the laminate of Example 4 was obtained by following the same steps as in Example 1.

[0093] (Example 5)

[0094] Except that CHEMIPEARL S100 and CHEMIPEARL W300 were combined in a solids ratio of 100 / 3.5 and coated onto clay-coated paper, the laminate of Example 5 was obtained by following the same steps as in Example 1.

[0095] (Example 6)

[0096] Except that CHEMIPEARL S100 and CHEMIPEARL W300 were combined in a solids ratio of 100 / 7.5 and coated onto clay-coated paper, the laminate of Example 6 was obtained by following the same steps as in Example 1.

[0097] (Example 7)

[0098] Except that CHEMIPEARL S100 and CHEMIPEARL W300 are combined in a solids ratio of 100 / 20 and coated onto clay-coated paper, the laminate of Example 7 is obtained by following the same steps as in Example 1.

[0099] (Example 8)

[0100] Use the following materials to create the laminate.

[0101] • Paper substrate: Clay-coated paper (weight per unit area: 55g / m²) 2 Thickness: 50μm

[0102] • Tackifying coating: Aqueous polyolefin dispersion (CHEMIPEARL S100, manufactured by Mitsui Chemicals Co., Ltd.)

[0103] • Evaporated coating: Aluminum (thickness: 50nm)

[0104] • Coating layer: Aqueous polyolefin dispersion (CHEMIPEARL S100, manufactured by Mitsui Chemicals Co., Ltd.)

[0105] • Particles: Polyethylene particles (CHEMIPEARL W300, manufactured by Mitsui Chemicals, average particle size: 3μm)

[0106] (Comparative Example 1)

[0107] Except that no particles were used, the same steps as in Example 1 were followed to obtain the laminate of Comparative Example 1.

[0108] (Comparative Example 2)

[0109] Except for coating the aqueous polyolefin dispersion onto the clay-coated paper to a thickness of 5.0 μm after drying, the laminate of Comparative Example 2 was obtained by following the same steps as in Example 1.

[0110] <Sample Preparation>

[0111] Under a load of 100 kgf, samples were obtained by stacking five laminates obtained in each embodiment and comparative example in the same direction and then placing them in a constant temperature bath set at 40°C or 60°C for 3 days.

[0112] The samples obtained above were evaluated using the methods shown below. The results are shown in Tables 1 and 2.

[0113] <Determination of peel strength>

[0114] The specimens obtained from the laminates of each embodiment and comparative example were cut into pieces with a width of 15 mm and a length of 100 mm to serve as test pieces. The peel strength between the paper substrate and the coating layer was measured on these test pieces. The T-peel test was performed using a tensile testing machine (manufactured by Shimadzu Corporation) at a peel speed of 300 mm / min.

[0115] <Evaluation of Fiber Delamination>

[0116] The amount of paper fibers adhering to the coating layer peeled off in the above-mentioned peel strength test is determined visually. The evaluation is conducted according to the following criteria.

[0117] A: No paper fibers were observed adhering to the surface of the coating layer.

[0118] B: Paper fibers are thinly attached to the surface of the coating layer.

[0119] C: The coating layer has more paper fibers attached to its surface than B above.

[0120] D: Damaged paper substrate is attached to the surface of the coating layer.

[0121] It should be noted that a 3-day thermal process at 60°C is a very harsh condition. Even if the fiber peeling rating after 3 days at 60°C is "C" or "D", as long as the fiber peeling rating after 3 days at 40°C is "B", it can still be judged as a level suitable for full commercialization.

[0122] <Determination of heat seal strength>

[0123] Two laminates were overlapped with the paper substrate facing outwards, and heat-sealed using a heat sealer at 0.2 MPa, 120°C, and 1 second. A T-peel test was then conducted using a tensile testing machine (manufactured by Shimadzu Corporation) at a peel speed of 300 mm / min.

[0124]

[0125]

[0126] Symbol Explanation

[0127] 1: Paper substrate, 2: Coating layer, 3: Clay coating layer, 4: Evaporated layer, 5: Particles, 10, 20, 30: Laminate, S1, S3: Sample, S2: Laminate.

Claims

1. A laminated body, comprising: Paper substrate, Coating layer containing polyolefin resin, Multiple particles fixed in the coating layer, and The vapor-deposited layer located between the paper substrate and the coating layer. The particle size is larger than the thickness of the coating layer. The particles are made of the same polyolefin resin as the coating layer. The particle size R is 0.2–6.5 μm. The ratio R / T of the particle size R to the coating thickness T is 1.05 to 2.

0. The ratio A / B of the mass A of the coating layer to the mass B of the particles is 100 / 20 to 100 / 0.

2. The paper substrate is any one of the following: fully soluble pulp paper, special fully soluble pulp paper, coated paper, art paper, cast coated paper, molding paper, kraft paper, and glassine paper.

2. The laminate according to claim 1, wherein the peel strength, measured after the following process, is 0.1 N / 15 mm or less, <Determination of peel strength> (a1) The process of placing the sample in a constant temperature bath set at 40°C for 3 days under a load of 100 kgf on a sample formed by stacking 5 of the laminates in the same direction. (b1) The process of peeling the two laminates together from the sample after the process described in (a1); (c1) The procedure of performing a T-type peel test on the two laminates at a peeling speed of 300 mm / min.

3. The laminate according to claim 1, wherein the heat-sealing strength, measured after the following process, is 2.1 N / 15 mm or higher. <Determination of heat seal strength> (a2) The process of placing the sample in a constant temperature bath set at 40°C for 3 days under a load of 100 kgf on a sample formed by stacking 5 of the laminates in the same direction. (b2) The process of peeling the two laminates from the sample after the process described in (a2); (c2) A process of heat-sealing the coating layers of the two laminates together under conditions of pressure 0.2 MPa, temperature 120°C and time 1 second; (d2) The process of performing a T-type peel test on the sample obtained in step (c2) at a peeling speed of 300 mm / min.

4. The laminate according to any one of claims 1 to 3, wherein, The ratio A / B of the mass A of the coating layer to the mass B of the particles is 100 / 20 to 100 / 7.

5.

5. The roll of the laminate according to any one of claims 1 to 4.

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