Laminate, roll body, sheet body, and method for producing adhesive film

Abstract

A laminate (25) according to the present invention comprises a first base material (21), a second base material (22), and an adhesive layer (20) that is provided between the first base material (21) and the second base material (22) and contains a thermoplastic resin. The first base material (21) and the second base material (22) are each composed of a material different from that of the adhesive layer (20). At least one of the first base material (21) and the second base material (22) has a water vapor transmission rate of 50 g / m2 / day or more at a temperature of 70°C and a humidity of 90% RH. A roll body according to the present invention comprises a winding core and a laminate (25) according to the present invention, which is wound around the outer circumference of the winding core. In a sheet body according to the present invention, two or more laminates according to the present invention are layered. A method for producing an adhesive film according to the present invention includes: a step for producing a laminate (25) by bonding a first base material (21) and a second base material (22) to an adhesive layer (20) that contains a thermoplastic resin; and a step for removing, from the laminate (25), the first base material (21) and / or the second base material (22). At least one of the first base material (21) and the second base material (22) is composed of a material different from that of the adhesive layer (20). At least one of the first base material (21) and the second base material (22) has a water vapor transmission rate of 50 g / m2 / day or more at a temperature of 70°C and a humidity of 90% RH. The present invention can provide a laminate capable of suppressing a decrease in adhesive force of an adhesive layer due to lamination of base materials, a roll body formed from the laminate, a sheet body formed from the laminate, and a method for producing an adhesive film that can be obtained from the laminate.

Description

Methods for manufacturing laminates, rolls, sheets, and adhesive films

[0001] The present invention relates to a method for manufacturing laminates, rolls, sheets, and adhesive films.

[0002] In recent years, adhesive sheets have been used in electronic devices such as display devices and touch panels, as well as in laminated glass incorporating electrical components such as dimmable films (electronically equipped laminated glass). For example, it is known that an adhesive sheet containing polyvinyl acetal resin is placed between the dimmable film and each glass plate to integrate the two glass plates and the dimmable film via the adhesive sheet (see, for example, Patent Document 1). Furthermore, in the manufacturing processes of electronic devices and electronically equipped laminated glass, adhesive films with separators are used to prevent the adhesion of foreign matter (see, for example, Patent Document 2).

[0003] International Publication No. 2019 / 066042, JP 2023-543283

[0004] Incidentally, when a substrate such as a separator is laminated onto an adhesive film, the adhesive strength of the resulting adhesive film sometimes decreases and becomes insufficient.

[0005] Therefore, the object of the present invention is to provide a laminate that can suppress the decrease in adhesive strength of the adhesive layer due to the lamination of substrates, a roll of the laminate, a sheet of the laminate, and a method for producing an adhesive film obtained from the laminate.

[0006] As a result of diligent research, the inventors have found that even if they try to adjust the moisture content of the adhesive film under storage conditions or during manufacturing, if the water vapor permeability of the substrate is low, the moisture absorption of the adhesive film by the substrate is inhibited, resulting in insufficient adhesion of the resulting adhesive film. Based on this, they have completed the present invention. The present invention provides the following [1] to

[13] . [1] A first substrate, a second substrate, and an adhesive layer containing a thermoplastic resin provided between the first substrate and the second substrate, wherein the first substrate and the second substrate are made of a different material from the adhesive layer, and the water vapor permeability of at least one of the first substrate and the second substrate at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２[2] A laminate having a water vapor transmission rate of 50 g / m² at a temperature of 70°C and a humidity of 90% RH for the first substrate and the second substrate. ２ The laminate described in [1] above, wherein the water vapor transmission rate of at least one of the first substrate and the second substrate at a temperature of 23°C and a humidity of 90% RH is 4 g / m². [3] ２[1] or [2] above, wherein the density is 1 / day or more. [4] The laminate according to any one of [1] to [3] above, wherein the thermoplastic resin is an ethylene-vinyl acetate copolymer or a polyvinyl acetal resin. [5] The laminate according to [4] above, wherein the blockiness of the constituent units having hydroxyl groups in the polyvinyl acetal resin is 0.25 or more and 0.38 or less. [6] The laminate according to [4] above, wherein the amount of hydroxyl groups in the polyvinyl acetal resin is 26 mol% or more and 33 mol% or less. [7] The laminate according to any one of [1] to [6] above, wherein the adhesive layer has a multilayer structure of two or more layers. [8] The laminate according to any one of [1] to [7] above, wherein the resin constituting the first substrate and the second substrate is at least one resin selected from the group consisting of polyester resin, polymethylpentene resin, triacetylcellulose resin (TAC), and polyamide resin, and the thickness of the first substrate and the second substrate is 10 μm or more and 200 μm or less, respectively. [9] The laminate according to any one of [1] to [8] above, wherein at least one of the first substrate and the second substrate is provided with an adhesion strength adjusting layer on the surface facing the adhesive layer, and the thickness of the adhesion strength adjusting layer is 10 μm or less.

[10] The laminate according to any one of [1] to [9] above, wherein the adhesion strength of at least one of the first substrate and the second substrate to the adhesive layer is 0.03 N / 25 mm or more.

[11] A roll body comprising a winding core and the laminate according to any one of [1] to

[10] above wound around the outer circumference of the winding core.

[12] A single-sheet body having two or more laminates according to any one of [1] to

[10] above.

[13] A method for manufacturing a laminate comprising the steps of: bonding a first substrate to one side of an adhesive layer containing a thermoplastic resin, and bonding a second substrate to the other side of the adhesive layer; and peeling off at least one of the first substrate and the second substrate from the laminate, wherein the first substrate and the second substrate are made of a different material from the adhesive layer, and the water vapor transmission rate of at least one of the first substrate and the second substrate at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２A method for manufacturing adhesive films with a lifespan of at least one day.

[0007] According to the present invention, it is possible to provide a laminate that can suppress the decrease in adhesive strength of the adhesive layer due to the lamination of substrates, a roll of the laminate, a sheet of the laminate, and a method for manufacturing an adhesive film obtained from the laminate.

[0008] Figure 1 is a diagram illustrating one embodiment of the method for manufacturing the laminate according to the present invention. Figure 2 is a diagram illustrating one embodiment of the method for manufacturing the laminate according to the present invention. Figure 3 is a diagram showing the manufacturing apparatus used to manufacture the laminate of Example 4. Figure 4 is a diagram showing the manufacturing apparatus used to manufacture the laminate of Example 4.

[0009] The present invention will now be described in detail. The laminate of the present invention comprises a first substrate, a second substrate, and an adhesive layer containing a thermoplastic resin provided between the first substrate and the second substrate.

[0010] <First Substrate and Second Substrate> The first substrate and the second substrate are not particularly limited as long as they are made of a different material from the adhesive layer. Examples of the first substrate and the second substrate include resin film, release paper, mesh material, metal, and prepreg. The first and second substrates are preferably release substrates that can be easily peeled off from the adhesive layer. These substrates can be used individually or in combination of two or more. For example, a resin film laminated with mesh material or metal can also be used. From the viewpoint of providing good handling while maintaining high water vapor permeability, resin film is more preferable as the first and second substrates. At least one of the first and second substrates may have an adhesive strength adjusting layer as needed. Therefore, when using resin film as the first and second substrates, at least one of the first and second substrates may consist of a resin film substrate alone, or an adhesive strength adjusting layer may be provided on at least one side of the resin film. The adhesive strength adjusting layer is preferably provided on the adhesive layer side of at least one of the first and second substrates.

[0011] The first and second substrates, i.e., the film substrates constituting the resin film, are not particularly limited as long as their water vapor transmission rate is within a predetermined range as described below. Examples include polyester resin, polymethylpentene resin (PMP), triacetylcellulose resin (TAC), polyamide resin (PA), polyimide resin, fluororesins such as tetrafluoroethylene, silicone resin, liquid crystal polymer, polysulfone resin, polyether ether ketone resin, polyether ketone ketone resin, modified polyphenylene ether, polyphenylene sulfide resin, polycarbonate resin, or polybenzimidazole resin. Among these, polyester resin, polymethylpentene resin (PMP), triacetylcellulose resin, and polyamide resin are preferred from the viewpoint of achieving both heat resistance during laminate manufacturing and high water vapor transmission rate.

[0012] Examples of polyester resins include polyethylene terephthalate resin (PET), polyethylene terephthalate glycol resin (PETG), polybutylene naphthalate resin (PBN), polybutylene terephthalate resin (PBT), polytrimethylene terephthalate resin (PTT), polyhexamethylene terephthalate resin (PHT), copolymer polyethylene terephthalate / isophthalate resin (PET / PEI), polyethylene naphthalate resin (PEN), and polylactic acid resin. PET and PEN are preferred among the polyester resins, with PET being more preferred.

[0013] Examples of polyamide resins include nylon 6, nylon 66, nylon 610, nylon 9, nylon 11, nylon 12, nylon 13, Q2 nylon, ultra-high polymerization nylon, transparent nylon, and microcrystalline nylon. Among these, nylon 6 is more preferred. In the first and second substrates, the resin constituting the resin film may be used alone or in combination of two or more types.

[0014] Among the above, PET, TAC, and PA are preferred, and TAC and PA are more preferred. Therefore, the film substrate constituting the resin film is preferably a polyester resin film, PMP film, TAC film, and PA film. Among these, TAC film and PA film are more preferred from the viewpoint of increasing water vapor permeability, and PET film and PMP film are more preferred from the viewpoint of preventing excessively high water vapor permeability in a normal temperature environment and from the viewpoint of handling, with PET film being even more preferred. These resins may be used individually or in combination of two or more. The resin film may also consist of a single layer or have a multilayer structure of two or more layers. In the case of a multilayer structure of two or more layers, the resins constituting each layer may be the same or different.

[0015] In at least one of the first and second substrates, the adhesion adjustment layer may be formed with a release agent, a silicone-based release agent, or a non-silicone-based release agent. In the case of a silicone-based release agent, it is preferable to use a silicone resin as the resin in the release agent. Examples of resins used in non-silicone-based release agents include fluororesins, melamine resins, epoxy resins, phenolic resins, and acrylic resins. Among these, silicone-based release agents are preferred. In addition, in at least one of the first and second substrates, the adhesion adjustment layer may be formed with a primer such as a urethane resin or polyethylene resin. This makes it possible to increase the adhesion strength (peel strength) of the substrate to the adhesive layer if the adhesion of the substrate to the adhesive layer is insufficient. When the substrate has an adhesion adjustment layer, it is preferable that both the first and second substrates have an adhesion adjustment layer. Furthermore, the adhesion adjustment layer may have functions other than adhesion adjustment added, such as an antistatic agent. The thickness of the adhesion adjustment layer is not particularly limited, but is preferably 10 μm or less, more preferably 5 μm or less, even more preferably 3 μm or less, preferably 0.01 μm or more, more preferably 0.05 μm or more, and even more preferably 0.08 μm or more.

[0016] As the release paper, any known release paper may be used, preferably one in which a release layer is provided on at least one side of the paper substrate. The adhesion adjustment layer is preferably provided on the side on which the adhesive layer is laminated. The adhesion adjustment layer is preferably formed with a release agent, and specific examples of release agents are as described above. Furthermore, as the paper substrate used for the release paper, it is preferable to use one that has been processed to prevent the release agent from immersing in the base paper, for example, glassine paper, smear-coated paper, PE laminate paper, or PET laminate paper may be used.

[0017] Further, examples of the mesh material include resin meshes, metal meshes and the like. The resin mesh may be a woven fabric, a knitted fabric or the like composed of resin fibers, or may be a non-woven fabric or the like. As the resin used for the resin mesh, those listed as the resins used for the base film described above can be appropriately used. Further, examples of the metal mesh include aluminum meshes, stainless steel meshes, copper meshes and the like. Further, the metal may be a metal foil such as an aluminum foil, a stainless steel foil, or a copper foil, or a metal plate. The metal plate only needs to have a reduced thickness to exhibit flexibility, and examples thereof include an aluminum plate, a stainless steel plate, a copper plate and the like. Examples of the prepreg include those obtained by impregnating reinforcing fibers such as glass fibers and carbon fibers with a matrix resin such as an epoxy resin, a modified polyphenylene ether resin, a polyimide resin, or a polybenzoxazole resin.

[0018] The water vapor transmission rate of at least one of the first base material and the second base material at a temperature of 70°C and a humidity of 90% RH is 50 g / m ２ / day or more. The water vapor transmission rate of both the first base material and the second base material at a temperature of 70°C and a humidity of 90% RH is 50 g / m ２ / day or less, even if an attempt is made to adjust the moisture content in the adhesive layer depending on the storage environment or before winding during production, the moisture absorption of the adhesive layer by the base material becomes insufficient, and the adhesive force of the adhesive layer may be significantly reduced compared to the adhesive force of the adhesive layer in a case where no base material is laminated. From such a viewpoint, the water vapor transmission rate of at least one of the first base material and the second base material at a temperature of 70°C and a humidity of 90% RH is preferably 70 g / m ２ / day or more, more preferably 200 g / m ２ / day or more, even more preferably 500 g / m ２ / day or more, still more preferably 1000 g / m ２ / day or more, still even more preferably 2000 g / m ２It is 1 / day or more. The upper limit of the range of water vapor transmission rate at a temperature of 70°C and a humidity of 90%RH for at least one of the first and second substrates is not particularly limited, but from the viewpoint of suppressing foaming of the adhesive layer, it is 8000 g / m². ２ It is preferable that the water vapor transmission rate is less than or equal to / day. From the viewpoint of moisture absorption of the adhesive layer, it is preferable that the range of water vapor transmission rates of both the first and second substrates at a temperature of 70°C and a humidity of 90% RH is within the above range. The water vapor transmission rate of the substrate at a temperature of 70°C and a humidity of 90% RH can be measured in accordance with JIS K7129. Furthermore, the water vapor transmission rate of the substrate at a temperature of 70°C and a humidity of 90% RH can be adjusted by the type of resin constituting the substrate, the thickness of the substrate, etc. Note that the water vapor transmission rates of the first and second substrates at a temperature of 70°C and a humidity of 90% RH may be the same or different from each other.

[0019] The water vapor transmission rate of at least one of the first and second substrates at a temperature of 23°C and a humidity of 90% RH is preferably 4 g / m³. ２ The value is 4 g / m³ or more. The water vapor transmission rate of at least one of the first and second substrates at a temperature of 23°C and a humidity of 90% RH is 4 g / m³. ２ If the humidity is 1 / day or more, the adhesive layer will absorb moisture during storage of the laminate or during manufacturing, which can suppress changes in the adhesive strength of the adhesive layer compared to the adhesive strength of the adhesive layer when the substrate is not laminated. In addition, it can suppress deterioration of the water vapor dissipation ability of the substrate. From this viewpoint, the water vapor transmission rate of at least one of the first and second substrates at a temperature of 23°C and a humidity of 90% RH is more preferably 10 g / m². ２ The amount is 50 g / m² or more per day, and more preferably 50 g / m². ２ The amount is 80 g / m² or more per day, and more preferably 80 g / m². ２ It is 100 g / m² or more per day, and more preferably 100 g / m². ２It is 1000 g / m² or more. The upper limit of the range of water vapor transmission rate at a temperature of 23°C and a humidity of 90% RH for at least one of the first and second substrates is not particularly limited, but is usually 1000 g / m². ２ It is less than or equal to / day. This suppresses deterioration of the penetration of the substrate. From the viewpoint of moisture absorption of the adhesive layer, it is preferable that the range of water vapor transmission rates of both the first and second substrates at a temperature of 23°C and a humidity of 90% RH is within the above range. The water vapor transmission rate of the substrate at a temperature of 23°C and a humidity of 90% RH can be measured in accordance with JIS K7129. Furthermore, the water vapor transmission rate of the substrate at a temperature of 23°C and a humidity of 90% RH can be adjusted by the type of resin constituting the substrate, the thickness of the substrate, etc. Note that the water vapor transmission rates of the first and second substrates at a temperature of 23°C and a humidity of 90% RH may be the same or different from each other.

[0020] The adhesive strength of at least one of the first and second substrates to the adhesive layer is preferably 0.03 N / 25 mm or more. When the adhesive strength of at least one of the first and second substrates to the adhesive layer is 0.03 N / 25 mm or more, it is possible to suppress the peeling of one of the first and second substrates from the adhesive layer when the laminate is not in use. From this viewpoint, the adhesive strength of at least one of the first and second substrates to the adhesive layer is more preferably 0.05 N / 25 mm or more, even more preferably 0.1 N / 25 mm or more, and even more preferably 0.3 N / 25 mm or more. Furthermore, the adhesive strength of at least one of the first and second substrates to the adhesive layer is preferably 2.0 N / 25 mm or less. If the adhesive strength of at least one of the first and second substrates to the adhesive layer is 2.0 N / 25 mm or less, then at least one of the first and second substrates can be easily peeled off the adhesive layer when the laminate is in use. From this viewpoint, the adhesive strength of at least one of the first and second substrates to the adhesive layer is more preferably 5.0 N / 25 mm or less, even more preferably 4.0 N / 25 mm or less, and even more preferably 3.0 N / 25 mm or less. From the viewpoint of suppressing the peeling of the first and second substrates from the adhesive layer when the laminate is not in use, and from the viewpoint of being able to easily peel the first and second substrates from the adhesive layer when the laminate is in use, it is preferable that the adhesive strength of both the first and second substrates to the adhesive layer be within the above range. The adhesive strength of the substrate to the adhesive layer can be determined by measuring the 180° peel adhesion of the substrate to the adhesive layer by a method in accordance with JIS Z 0237. Furthermore, the adhesive strength of the substrate to the adhesive layer can be adjusted by the type of resin constituting the substrate, the type of resin constituting the adhesive strength adjustment layer provided on the surface of the substrate, the thickness of the adhesive strength adjustment layer, the composition of the adhesive layer, the thickness of the adhesive layer, etc. Note that the adhesive strength of the first substrate and the second substrate to the adhesive layer may be the same or different.

[0021] The thickness of the first substrate and the second substrate is preferably 10 μm or more and 200 μm or less. When the thickness of the first substrate and the second substrate is 10 μm or more and 200 μm or less, the handling of the laminate becomes easier and the water vapor transmission rate can be easily adjusted to a desired range. From this viewpoint, the thickness of the first substrate and the second substrate is more preferably 15 μm or more and 150 μm or less, and even more preferably 20 μm or more and 130 μm or less. The thicknesses of the first substrate and the second substrate may be the same or different.

[0022] The second base material may be the same as the first base material, or it may be different. However, it is preferable that the second base material is the same as the first base material.

[0023] In this invention, by setting the water vapor permeability of the first substrate and the second substrate to a predetermined level or higher, the decrease in adhesive strength of the adhesive layer due to the lamination of substrates can be suppressed more effectively. Even if the water vapor permeability of one of the first and second substrates is not above the predetermined level, the adhesive layer can be allowed to absorb moisture through the substrate with a water vapor permeability of the predetermined level or higher, thus suppressing the decrease in adhesive strength of the adhesive layer due to the lamination of substrates.

[0024] <Adhesive layer> As mentioned above, the adhesive layer contains a thermoplastic resin.

[0025] [Thermoplastic Resin] The adhesive layer in the laminate of the present invention contains a thermoplastic resin, and more specifically, it is preferably made of a thermoplastic resin composition containing a thermoplastic resin. Examples of thermoplastic resins include polyvinyl acetal resin, polyvinyl alcohol resin (PVA), polyurethane resin (PU), ethylene-vinyl acetate copolymer resin (EVA), ethylene-vinyl acetate copolymer saponified product (EVOH), ethylene-methacrylic acid copolymer resin, (meth)acrylic resin, ionomer resin, isobutylene resin, styrene-isoprene copolymer resin, and styrene-butadiene copolymer resin. These thermoplastic resins may be used individually or in combination of two or more. Among these thermoplastic resins, ethylene-vinyl acetate copolymer resin, polyvinyl acetal resin, polyurethane resin, and ionomer resin are preferred from the viewpoint of adhesion, ethylene-vinyl acetate copolymer resin (EVA) and polyvinyl acetal resin are more preferred, polyvinyl acetal resin is even more preferred from the viewpoint of adhesion to glass and ease of improving the adhesion of the adhesive layer by moisture absorption, and polyvinyl butyral resin (PVB) is even more preferred.

[0026] (Polyvinyl acetal resin) The polyvinyl acetal resin used as the thermoplastic resin in the thermoplastic resin composition may be a modified polyvinyl acetal resin or an unmodified polyvinyl acetal resin. As described later, the modified polyvinyl acetal resin only needs to have structures other than acetal groups, hydroxyl groups, and acetyl groups (modified groups), and preferably has modified groups in its side chains. Polyvinyl acetal resin is obtained by acetalizing polyvinyl alcohol with an aldehyde and further reacting it with a modifying agent as needed. In addition, to obtain a modified polyvinyl acetal resin, modified polyvinyl alcohol may be used as the raw material polyvinyl alcohol.

[0027] <Degree of Acetalization> The degree of acetalization of polyvinyl acetal resin is preferably 65 mol% or more and 75 mol% or less. When the degree of acetalization of polyvinyl acetal resin is 65 mol% or more, the number of hydroxyl groups in the polyvinyl acetal resin decreases, and the adhesive film becomes sufficiently flexible. Furthermore, when the degree of acetalization of polyvinyl acetal resin is 75 mol% or less, the adhesion to substrates such as inorganic glass becomes good. From this viewpoint, the degree of acetalization of polyvinyl acetal resin is more preferably 67 mol% or more and 74 mol%, even more preferably 68 mol% or more and 73 mol%, and even more preferably 69 mol% or more and 72 mol% or less. Note that when the acetal group is a butyral group and the polyvinyl acetal resin is a polyvinyl butyral resin, the degree of acetalization refers to the degree of butyralization.

[0028] The degree of acetalization described above is a value expressed as a percentage of the mole fraction obtained by dividing the total amount of ethylene groups in the main chain (the difference between the amount of ethylene groups to which hydroxyl groups and the amount of ethylene groups to which acetyl groups are attached) by the total amount of ethylene groups in the main chain. The degree of acetalization (degree of butyralization) can be measured, for example, by NMR. The NMR measurement conditions are as follows: A 1H-NMR measurement is performed using a 400 MHz spectrometer with a nuclear magnetic resonance (NMR) spectrometer (Bruker, product name "AVANCE III HD"). PVB is dissolved in deuterated dimethyl sulfoxide (DMSO) to a concentration of 1% by mass, and the x-axis represents the chemical shift in ppm. The chemical shift reference is set to DMSO-d6 at 2.49 ppm for measurement.

[0029] <Weight Average Molecular Weight> The weight average molecular weight (Mw) of the polyvinyl acetal resin is preferably 220000 or more. When the weight average molecular weight (Mw) of the polyvinyl acetal resin is 220000 or more, the impact resistance of the polyvinyl acetal resin can be improved. From such a viewpoint, the weight average molecular weight (Mw) of the polyvinyl acetal resin is more preferably 230000 or more, further preferably 240000 or more, and even more preferably 260000 or more. In addition, the weight average molecular weight (Mw) of the polyvinyl acetal resin is preferably 310000 or less. When the weight average molecular weight (Mw) of the polyvinyl acetal resin is 310000 or less, the resin film can have sufficient flexibility. Moreover, when the adherend is glass, scattering of glass can be more effectively suppressed. From such a viewpoint, the weight average molecular weight (Mw) of the polyvinyl acetal resin is more preferably 305000 or less, further preferably 300000 or less, and even more preferably 290000 or less.

[0030] The weight average molecular weight (Mw) of the polyvinyl acetal resin is measured by gel permeation chromatography. The above weight average molecular weight can be measured by the following measurement method. A measurement sample is dissolved at a concentration of 0.05 mass% in an N-methyl-2-pyrrolidone solution to which lithium bromide is added so as to be 10 mM, and filtered using a syringe filter (manufactured by Merck, Millex-LH 0.45 μm). After filtration, measurement is performed using gel permeation chromatography (manufactured by Waters, e2690), and calculation is performed using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample. In addition, Shodex GPC KF-806L (manufactured by Showa Denko KK) is used as the column, and an N-methyl-2-pyrrolidone solution to which lithium bromide is added so as to be 10 mM is used as the eluent.

[0031] <Aldehydes> The polyvinyl acetal resin is preferably a polyvinyl acetal resin obtained by acetalizing polyvinyl alcohol (PVA) with an aldehyde. The aldehyde is not particularly limited, but generally, aldehydes having 1 to 10 carbon atoms are preferably used. The aldehydes having 1 to 10 carbon atoms are not particularly limited, and examples include n-butyraldehyde, isobutyraldehyde, n-valeraldehyde, 2-ethylbutyraldehyde, n-hexylaldehyde, n-octylaldehyde, n-nonylaldehyde, n-decylaldehyde, formaldehyde, acetaldehyde, and benzaldehyde. These aldehydes may be used alone or in combination of two or more. Among the above, n-butyraldehyde, n-hexylaldehyde, and n-valeraldehyde are preferred, and n-butyraldehyde is more preferred. Therefore, polyvinyl butyral resin (PVB) is preferred as the polyvinyl acetal resin.

[0032] <Polyvinyl Alcohol (PVA)> Polyvinyl alcohol (PVA), used as a raw material for polyvinyl acetal resin, is obtained by saponifying polyvinyl esters such as polyvinyl acetate. The degree of saponification of polyvinyl alcohol is generally 70 to 99.9 mol%. The average degree of polymerization of PVA is preferably 200 or higher, more preferably 500 or higher, even more preferably 1000 or higher, and even more preferably 1500 or higher. Setting the average degree of polymerization above the above lower limit increases the penetration resistance of laminated glass when used in laminated glass. Furthermore, the average degree of polymerization of PVA is preferably 5000 or lower, more preferably 4000 or lower, even more preferably 3500 or lower, and even more preferably 2500 or lower. The average degree of polymerization of polyvinyl alcohol is determined by a method in accordance with JIS K6726 "Test Method for Polyvinyl Alcohol". Furthermore, when two or more types of polyvinyl alcohol are used as raw materials, the average degree of polymerization of the polyvinyl alcohol can be estimated by calculation from the average degree of polymerization of each polyvinyl alcohol. Furthermore, two or more types of polyvinyl alcohol with different average degrees of polymerization may be used as the raw material for the polyvinyl acetal resin.

[0033] <Hydroxyl group content> The hydroxyl group content of the polyvinyl acetal resin is preferably 35 mol% or less. By setting the hydroxyl group content to 35 mol% or less, the flexibility of the adhesive layer can be further improved. From such a viewpoint, the hydroxyl group content is more preferably 34 mol% or less, and still more preferably 33 mol% or less. The hydroxyl group content of the polyvinyl acetal resin is preferably 15 mol% or more. By setting the hydroxyl group content to 15 mol% or more, the adhesive layer tends to absorb moisture easily, and the adhesive force is easily improved. From such a viewpoint, the hydroxyl group content is more preferably 20 mol% or more, and still more preferably 25 mol% or more. Also when a polyvinyl butyral resin is used as the polyvinyl acetal resin, from the same viewpoint, the hydroxyl group content is preferably 35 mol% or less, more preferably 34 mol% or less, still more preferably 33 mol% or less, and is preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, and even more preferably 26 mol% or more. The hydroxyl group content of the polyvinyl acetal resin is a value expressed as a percentage of the mole fraction obtained by dividing the amount of ethylene groups to which hydroxyl groups are bonded by the total amount of ethylene groups in the main chain. The hydroxyl group content is calculated, for example, from the degree of acetalization [%] and the degree of acetylation [%] measured by NMR, using the formula: Hydroxyl group content [%] = 100 - (degree of acetalization [%] + degree of acetylation [%]).

[0034] <Degree of Acetylation> The degree of acetylation of the polyvinyl acetal resin is preferably 30 mol% or less, more preferably 20 mol% or less, even more preferably 10 mol% or less, and even more preferably 2 mol% or less. When the degree of acetylation is below the above upper limit, the moisture resistance of the thermoplastic resin composition is increased. Furthermore, the degree of acetylation is not particularly limited, but is preferably 0.01 mol% or more, and more preferably 0.1 mol% or more. The degree of acetylation is a value expressed as a percentage of the mole fraction obtained by dividing the amount of ethylene groups to which acetyl groups are bonded by the total amount of ethylene groups in the main chain. The degree of acetylation can be measured, for example, by NMR. The NMR measurement conditions are as follows: A nuclear magnetic resonance (NMR) spectrometer (manufactured by Bruker, trade name "AVANCE III HD") is used to perform 1H-NMR measurement using a 400 MHz spectrometer. PVB is dissolved in deuterated dimethyl sulfoxide (DMSO) to a concentration of 1% by mass. The x-axis represents the chemical shift in ppm, and the chemical shift reference is set to 2.49 ppm for DMSO-d6.

[0035] <Blocking properties of constituent units having hydroxyl groups> The blocking properties of constituent units having hydroxyl groups in polyvinyl acetal resin are preferably 0.20 or more and 0.40 or less. When the blocking properties of constituent units having hydroxyl groups in polyvinyl acetal resin are 0.20 or more, it becomes easier to allow the adhesive layer to absorb a certain amount of water, further improving the adhesion to the adherend. When the blocking properties of constituent units having hydroxyl groups in polyvinyl acetal resin are 0.40 or less, it is possible to suppress the hardening of the adhesive layer. From this viewpoint, the blocking properties of constituent units having hydroxyl groups in polyvinyl acetal resin are more preferably 0.25 or more and 0.38 or less, even more preferably 0.26 or more and 0.35 or less, and particularly preferably 0.30 or more and 0.33 or less. The blocking properties of the above-mentioned constituent units having hydroxyl groups were determined by the following formula, using the peak intensity around 43.8 ppm, which originates from two types of structures indicating the randomness of the hydroxyl groups as measured by NMR, and the peak intensity around 45.3 ppm, which indicates the degree of blocking of the hydroxyl groups: Blocking properties of constituent units having hydroxyl groups = (Peak intensity around 45.3 ppm / Peak intensity around 43.8 ppm, which originates from two types of structures)). Note that NMR can be measured by the method described in the examples below. Furthermore, the blocking properties of constituent units having hydroxyl groups can be adjusted by the aging temperature and aging time in the aging process of the polyvinyl acetal resin manufacturing method described later.

[0036] <Modified Polyvinyl Acetal Resin> The polyvinyl acetal resin used as the thermoplastic resin in a thermoplastic resin composition is preferably an unmodified polyvinyl acetal resin, but it may also be a modified polyvinyl acetal resin. A modified polyvinyl acetal resin has structures other than acetal groups, hydroxyl groups, and acetyl groups (modified groups), and preferably has modified groups in its side chains. Examples of modified groups include those having a polyalkylene oxide structure in the side chain, and those having alkyl groups other than acetal groups and acetyl groups (for example, with about 2 to 30 carbon atoms) in the side chain. A preferred modified polyvinyl acetal resin is a polyalkylene oxide modified polyvinyl acetal resin, and a more preferred modified polyvinyl acetal resin is a polyethylene oxide modified polyvinyl acetal resin. The amount of modification is not particularly limited, but for example, it is about 0.1 mol% to 10 mol%. The amount of modification represents the ratio of functional groups to the total vinyl monomer units constituting the polyvinyl acetal resin.

[0037] (Method for producing polyvinyl acetal resin) Polyvinyl acetal resin is preferably produced by a manufacturing method that includes a mixing step of mixing the above-mentioned polyvinyl alcohol and the above-mentioned aldehyde, and a maturation step of maturing the mixture obtained in the mixing step.

[0038] In the mixing step, polyvinyl alcohol and aldehyde should be mixed according to the conventional method. In addition to polyvinyl alcohol and aldehyde, catalysts such as acid catalysts to promote the acetalization reaction may be added. For example, the aldehyde can be added to a mixture of polyvinyl alcohol and an acid catalyst under low temperature conditions of about 0 to 40°C. A solvent such as water is also usually added. Furthermore, when using two or more types of polyvinyl alcohol (for example, when using two or more types of polyvinyl alcohol with different molecular weights), it is best to mix the two or more types of polyvinyl alcohol with the aldehyde.

[0039] The above-mentioned aging process is not particularly limited, but for example, a catalyst such as an acid catalyst may be added to the mixture (reaction mixture) obtained in the mixing process, heated to the aging temperature, and held at the aging temperature for a certain period of time. In this manufacturing method, the acetalization of polyvinyl alcohol proceeds in the mixing and aging processes, and polyvinyl acetal resin is obtained. After the reaction mixture is held at the aging temperature for a certain period of time, it may be cooled as appropriate and neutralized, and then washed with water, dried, etc. as needed.

[0040] Examples of acid catalysts added in the mixing and maturation processes include inorganic acids such as hydrochloric acid, nitric acid, phosphoric acid, sulfuric acid, and boric acid. In the maturation process, the concentration of the acid catalyst should be adjusted to, for example, 0.5% by mass or more and 5% by mass or less, preferably 1% by mass or more and 2.5% by mass or less.

[0041] The maturation temperature in the maturation process is preferably relatively low, for example, 30°C to 70°C, preferably 30°C to 68°C, more preferably 35°C to 66°C, and even more preferably 40°C to 64°C. The time for holding at the above maturation temperature (maturation time) can be longer than a certain period, for example, 75 minutes to 180 minutes, preferably 90 minutes to 150 minutes, and more preferably 100 minutes to 140 minutes. By adjusting the maturation temperature and maturation time within the predetermined range as described above, it becomes easier to adjust the blockiness of the constituent units having hydroxyl groups within the desired range.

[0042] (Ethylene-vinyl acetate copolymer resin (EVA)) The ethylene-vinyl acetate copolymer resin may be a non-crosslinked type ethylene-vinyl acetate copolymer resin, or a high-temperature crosslinked type ethylene-vinyl acetate copolymer resin. In addition, ethylene-vinyl acetate modified resins such as ethylene-vinyl acetate copolymer saponified products and hydrolyzed products of ethylene-vinyl acetate can also be used as the ethylene-vinyl acetate copolymer resin.

[0043] The ethylene-vinyl acetate copolymer resin preferably has a vinyl acetate content of 10% to 50% by mass, more preferably 20% to 40% by mass, as measured in accordance with JIS K6924-2:1997. By setting the vinyl acetate content above these lower limits, the adhesion of the resin film to the substrate is improved. Furthermore, by setting the vinyl acetate content below these upper limits, the tensile strength of the resin film is increased.

[0044] (Plasticizer) The thermoplastic resin composition preferably contains a plasticizer in addition to the thermoplastic resin. By containing a plasticizer, the adhesive film becomes more flexible and its shock absorption properties can be further improved. The plasticizer is more preferably included in the thermoplastic resin composition when the thermoplastic resin is a polyvinyl acetal resin.

[0045] Examples of plasticizers include organic ester plasticizers, organophosphorus plasticizers such as organic phosphate ester plasticizers and organic phosphite ester plasticizers, organic ether plasticizers such as polyalkylene glycol plasticizers and polyoxyalkylene ether plasticizers, and alcohol plasticizers. Plasticizers may be used individually or in combination of two or more. Among the above, organic ester plasticizers and organic ether plasticizers are preferred.

[0046] Preferred organic ester plasticizers include monobasic organic acid esters and polybasic organic acid esters. Examples of monobasic organic acid esters include esters of glycol and monobasic organic acid. Examples of glycols include polyalkylene glycols in which each alkylene unit has 2 to 4 carbon atoms, preferably 2 or 3 carbon atoms, and the number of repeating alkylene units is 2 to 10, preferably 2 to 4. Alternatively, the glycol may be a monoalkylene glycol with 2 to 4 carbon atoms, preferably 2 or 3 carbon atoms (i.e., 1 repeating unit). Specific examples of glycols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, and butylene glycol. Examples of monobasic organic acids include organic acids having 3 to 10 carbon atoms, specifically butyric acid, isobutyric acid, caproic acid, 2-ethylbutyric acid, heptylic acid, n-octylic acid, 2-ethylhexylic acid, n-nonylic acid, and decylic acid.

[0047] Specific examples of monobasic organic acid esters include triethylene glycol di-2-ethyl butyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethylene glycol di-n-octanoate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, tetraethylene glycol di-2-ethylhexanoate, diethylene glycol di-2-ethyl butyrate, diethylene glycol di-2-ethylhexanoate, dipropylene glycol di-2-ethyl butyrate, and triethylene glycol Examples include di-2-ethylpentanoate, tetraethylene glycol di-2-ethyl butyrate, diethylene glycol dicapriate, triethylene glycol di-n-heptanoate, tetraethylene glycol di-n-heptanoate, triethylene glycol di-2-ethyl butyrate, ethylene glycol di-2-ethyl butyrate, 1,2-propylene glycol di-2-ethyl butyrate, 1,3-propylene glycol di-2-ethyl butyrate, 1,4-butylene glycol di-2-ethyl butyrate, and 1,2-butylene glycol di-2-ethyl butyrate.

[0048] Furthermore, examples of polybasic organic acid esters include ester compounds of dibasic organic acids having 4 to 12 carbon atoms, such as adipic acid, sebacic acid, and azelaic acid, and alcohols having 4 to 10 carbon atoms. The alcohols having 4 to 10 carbon atoms may be linear, branched, or cyclic. Specifically, examples include dibutyl sebacate, dioctyl azelaate, dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, diisononyl adipate, heptylnonyl adipate, dibutylcarbitol adipate, and mixed adipic acid esters. Oil-modified alkyd sebacate may also be used. Examples of mixed adipic acid esters include adipic acid esters made from two or more alcohols selected from alkyl alcohols having 4 to 9 carbon atoms and cyclic alcohols having 4 to 9 carbon atoms.

[0049] The organic ester plasticizer is not limited to the complete esters of the esters described above, but may also be a partial ester. For example, it may be a partial ester of a glycol and a monobasic organic acid, or a partial ester of a dibasic organic acid and an alcohol. Specifically, examples include triethylene glycol-mono-2-ethylhexanoate. Furthermore, it may be a partial ester of a trivalent or higher alcohol, such as glycerin, and a monobasic organic acid. Examples of monobasic organic acids include those having 3 to 24 carbon atoms, preferably 6 to 18 carbon atoms. Specific examples of partial esters of trivalent or higher alcohols and monobasic organic acids include mono or diesters of glycerin and stearic acid, and mono or diesters of glycerin and 2-ethylhexyl acid. Among the above, triethylene glycol-di-2-ethylhexanoate (3GO) is particularly preferred as the organic ester plasticizer.

[0050] Examples of organophosphorus plasticizers include phosphate esters such as tributoxyethyl phosphate, isodecylphenyl phosphate, and triisopropyl phosphate. Examples of polyalkylene glycol plasticizers include polyethylene glycol, polypropylene glycol (PPG), poly(ethylene oxide / propylene oxide) block copolymer, poly(ethylene oxide / propylene oxide) random copolymer, and polytetramethylene glycol, among which polypropylene glycol (PPG) is preferred.

[0051] Polyoxyalkylene ether plasticizers are ether compounds of a monohydric or polyhydric alcohol and a polyoxyalkylene. Specific examples of polyoxyalkylene ether plasticizers include polyoxyethylene hexyl ether, polyoxyethylene heptyl ether, polyoxyethylene octyl ether, polyoxyethylene-2-ethylhexyl ether, polyoxyethylene nonyl ether, polyoxyethylene decyl ether, polyoxyethylene allyl ether, polyoxyethylene allyl ether, polyoxyethylene glyceryl ether, polyoxypropylene glyceryl ether, polyoxyethylene diglyceryl ether, polyoxypropylene diglyceryl ether (DGP), and polyoxyalkylene pentaerythritol ether. Among these, polyoxypropylene diglyceryl ether (DGP) is preferred. The polyoxyalkylene ether plasticizer is preferably an ether compound of a polyhydric alcohol and a polyoxyalkylene, more preferably an ether compound of glycerin or diglycerin and a polyoxyalkylene, and even more preferably an ether compound of glycerin or diglycerin and a polyoxypropylene. Examples of alcohol-based plasticizers include various polyhydric alcohols such as butanediol, hexanediol, trimethylolpropane, and pentaerythritol. Among these, trimethylolpropane is preferred.

[0052] The above plasticizers can be used individually or in combination of two or more. Among the above plasticizers, triethylene glycol-di-2-ethylhexanoate (3GO), polyoxypropylene diglyceryl ether (DGP), and polypropylene glycol (PPG) are preferred, and triethylene glycol-di-2-ethylhexanoate (3GO) is more preferred.

[0053] The content of plasticizer in the thermoplastic resin composition is not particularly limited, but is preferably 20 parts by mass or more and 70 parts by mass or less per 100 parts by mass of thermoplastic resin. When the plasticizer content is 20 parts by mass or more, the resin film becomes moderately flexible and the adhesion of the resin film to glass plates and the like becomes good. On the other hand, when the plasticizer content is 70 parts by mass or less, separation of the plasticizer from the adhesive film is prevented. The above content of plasticizer is more preferably 25 parts by mass or more, even more preferably 30 parts by mass or more, and more preferably 65 parts by mass or less, even more preferably 60 parts by mass or less, even more preferably 55 parts by mass or less, and even more preferably 50 parts by mass or less.

[0054] The thermoplastic resin composition may contain, in addition to plasticizers, known additives used in combination with thermoplastic resins as appropriate. That is, the thermoplastic resin composition may consist of a thermoplastic resin alone, such as polyvinyl acetal resin, or it may consist of a thermoplastic resin and a plasticizer, but it may also contain additives other than plasticizers as needed. Specifically, additives other than plasticizers include ultraviolet absorbers, infrared absorbers, antioxidants, light stabilizers, adhesion modifiers, colorants (pigments or dyes), fluorescent whitening agents, crystal nucleating agents, etc. However, even when other components are blended into the thermoplastic resin composition, the thermoplastic resin composition is mainly composed of a thermoplastic resin, or the sum of the thermoplastic resin and plasticizer, and the total amount of thermoplastic resin and plasticizer is usually 70% by mass or more, preferably 80% by mass or more and 100% by mass or less, and more preferably 90% by mass or more and 100% by mass or less, based on the total amount of the resin layer.

[0055] The thickness of the adhesive layer is preferably 50 μm or more and 1 mm or less, more preferably 100 μm or more and 760 μm or less, and even more preferably 100 μm or more and 500 μm or less. A thickness of the adhesive layer greater than or equal to the lower limit enhances impact resistance and makes it easier to ensure adhesion to glass components and the like. On the other hand, a thickness of less than or equal to the upper limit prevents the laminate from becoming unnecessarily thick.

[0056] Irregularities may be formed on one or both of the surfaces of the adhesive layer on the first substrate side or the second substrate side. Furthermore, the surface roughness Rzjis94 of at least one surface of the adhesive layer is preferably 30 μm or less. When the surface roughness Rzjis94 of at least one surface of the adhesive layer is 30 μm or less, the pressure and temperature when bonding the adhesive layer to the adherend can be reduced. From this viewpoint, the surface roughness Rzjis94 of at least one surface of the adhesive layer is more preferably 10 μm or less, and even more preferably 7 μm or less. Furthermore, the surface roughness Rzjis94 of at least one surface of the adhesive layer is preferably 3 μm or more. When the surface roughness Rzjis94 of at least one surface of the adhesive layer is 3 μm or more, the bonding position of the adhesive layer can be adjusted, and the retention of air between the adhesive layer and the adherend can be suppressed when bonding the adhesive layer to the adherend. From this viewpoint, the surface roughness Rzjis94 of at least one surface of the adhesive layer is more preferably 4 μm or more, and even more preferably 5 μm or more. The surface roughness Rzjis94 of at least one surface of the adhesive layer can be measured by the method described in the examples below. The surface shape of the adhesive layer is transferred to the surface of the first and second substrates when manufactured by the manufacturing method described below, so that irregularities are formed on the surface of the substrate and the surface roughness can be adjusted to the desired range by appropriately adjusting the shape of these irregularities.

[0057] The adhesive layer may have a single-layer structure. When the adhesive layer consists of a single layer, the single-layer adhesive layer may have the composition described above for the thermoplastic resin composition. That is, the layer constituting the single-layer adhesive layer contains the thermoplastic resin described above, and may also contain a plasticizer if necessary, and may contain additives other than plasticizers as appropriate.

[0058] The adhesive layer may have a multilayer structure of two or more layers. Preferably, each resin layer of the adhesive layer has the composition described in the thermoplastic resin composition described above. That is, each resin layer preferably contains a thermoplastic resin as described in the thermoplastic resin composition described above, and may also contain a plasticizer as needed, and may be appropriately blended with additives other than plasticizers, and it is more preferable that each resin layer contains the polyvinyl acetal resin described above as the thermoplastic resin. Details of the thermoplastic resin, plasticizer, and additives in each resin layer of the multilayer adhesive layer, and details of the content of each component are as described in the thermoplastic resin composition described above. However, the thermoplastic resin that serves as the basis for the content is the thermoplastic resin contained in each layer. In a multilayer adhesive layer, each resin layer may have the same composition or different compositions. Furthermore, in a multilayer adhesive layer, it is preferable that at least the surface layer in contact with the first substrate has the composition described in the thermoplastic resin composition described above, and it is also preferable that the resin layer constituting the surface layer in contact with the first substrate contains the polyvinyl acetal resin described above as the thermoplastic resin. The details of each component in the surface layer are as described in the thermoplastic resin composition above.

[0059] [Rolls and Sheets] The rolls of the present invention comprise a winding core and a laminate of the present invention wound around the outer circumference of the winding core. The sheet is formed by laminating two or more of the laminate of the present invention. In the rolls and sheet, it is preferable that the first base material is wound or laminated so as to be in contact with the second base material.

[0060] [Method for Manufacturing a Laminate] An embodiment of the method for manufacturing a laminate according to the present invention will be described below. In the embodiment of the method for manufacturing a laminate described below, a laminate is obtained by laminating a first substrate and a second substrate onto an adhesive layer obtained by extruding a molten thermoplastic resin composition.

[0061] The manufacturing method according to this embodiment is carried out, for example, using the manufacturing apparatus shown in Figure 1. The manufacturing apparatus 10 in this embodiment includes an extruder 11, a mold 12, a feeding mechanism 13, a substrate heating mechanism 14, a laminating mechanism 15, an annealing section 16, a cooling mechanism 17, and a winding mechanism 18. In the manufacturing apparatus 10 in this embodiment, a laminate 25 obtained by laminating the first and second substrates 21 and 22 fed out from the feeding mechanism 13 with an adhesive layer 20 is wound into a roll shape by the winding mechanism 18 to obtain a roll-shaped laminate.

[0062] In this embodiment, the manufacturing method from unwinding the first and second base materials 21 and 22 to winding them by the winding mechanism 18 is performed between rolls, in a so-called roll-to-roll manner. When the base materials, laminates, etc. are conveyed by the roll-to-roll method, the base materials and laminates are not particularly limited, but for example, they may be conveyed by pinch rolls 41 and guided by guide rolls 42, 43, etc. However, the pinch rolls 41 and guide rolls 42, 43 shown in Figure 1 are merely examples and are not particularly limited.

[0063] The extruder 11 is not particularly limited as long as it can melt and knead the thermoplastic resin composition, and may be a single-screw extruder with one screw inside the cylinder, or a twin-screw extruder with two screws in parallel. The thermoplastic resin and other components to be added as needed are fed into the extruder 11 from the raw material supply port on the upstream side of the cylinder, and are melted and kneaded by the screws inside the cylinder as they are sent downstream. The melted and kneaded thermoplastic resin composition is supplied to a mold 12 connected to the extruder 11. In the mold 12, the thermoplastic resin composition is extruded in a sheet-like form as an adhesive layer 20 from a die provided in the mold 12 and supplied to the laminating mechanism 15. The temperature at which the thermoplastic resin composition is extruded from the mold 12 (i.e., the temperature of the thermoplastic resin composition at the mold exit) can be appropriately adjusted according to the type of thermoplastic resin, and specifically, it is preferable to set it to a temperature higher than the softening temperature of the thermoplastic resin. For example, when polyvinyl butyral is used as the thermoplastic resin, the extrusion temperature can be set to, for example, 180 to 220°C.

[0064] In the above description, the thermoplastic resin composition extruded from the mold 12 was described on the premise that a single-layer adhesive layer is extruded. However, a co-extrusion method may be employed to extrude multiple layers of adhesive. When multiple layers of adhesive are extruded, it is preferable to provide multiple extruders, connect the multiple extruders to the mold 12, and extrude the thermoplastic resin composition from the mold 12 in such a way that it forms multiple layers of adhesive. In this case, the thermoplastic resin compositions constituting each adhesive layer may be the same or different from one another.

[0065] The dispensing mechanism 13 comprises first and second dispensing mechanisms 31 and 32. Each of the first and second dispensing mechanisms 31 and 32 is fitted with a winding body in which the first base material 21 and the second base material 22 are wound in a roll shape. The first dispensing mechanism 31 dispenses the first base material 21 from the winding body and supplies the first base material 21 to the laminating mechanism 15. The second dispensing mechanism 32 dispenses the second base material 22 from the winding body and supplies the second base material 22 to the laminating mechanism 15. Typically, the first and second base materials 21 and 22 are supplied to the laminating mechanism 15 while being guided by one or more guide rolls (not shown) from the dispensing mechanism 13.

[0066] Furthermore, the first substrate 21 may undergo surface modification treatment before being laminated onto the adhesive layer 20, for example, plasma modification treatment or corona treatment. Similarly, the second substrate 22 may undergo surface modification treatment before being laminated onto the adhesive layer 20, for example, plasma modification treatment or corona treatment.

[0067] The plasma modification treatment is preferably performed on the surfaces of the first and second substrates 21 and 22 that are laminated onto the adhesive layer 20. Plasma modification treatment is performed on the first substrate 21, the second substrate 22, or both, which modifies the surface and makes it easier to adhere to the adhesive layer 20. For example, oxygen plasma can be used for the plasma treatment. The surface modification treatment is not particularly limited and may be performed, for example, after being fed out from the feeding mechanism 13 but before the adhesive layer 20 is laminated, but it is preferable to perform it after being fed out from the feeding mechanism 13 but before being heated by the substrate heating mechanism 14. The surface modification treatment may be performed while the substrate is being conveyed by roll-to-roll as described above, and for example, the plasma treatment may be performed using a known plasma processing device.

[0068] In this embodiment, the first and second substrates 21 and 22, which are dispensed from the first and second dispensing mechanisms 31 and 32, respectively, are preferably heated by the substrate heating mechanism 14 before being supplied to the laminating mechanism 15. Specifically, it is preferable that the first substrate 21 is heated by the substrate heating mechanism 14 (i.e., before laminating the first substrate 21 onto the adhesive layer 20) to a temperature above the softening temperature of the adhesive layer 20, which will be described later. By preheating the first substrate 21 to a temperature above the softening temperature, the first substrate 21 will shrink due to heat before being laminated onto the adhesive layer 20. Therefore, when the first substrate 21 is laminated onto the extruded adhesive layer 20, it is possible to prevent the first substrate 21 from shrinking due to the heat of the adhesive layer 20 and causing wrinkles.

[0069] The substrate heating mechanism 14 is not particularly limited, but examples include a heating roll and a heating space. The substrate heating mechanism 14 may heat the first and second substrates 21 and 22 in one of the paths supplied from the feeding mechanism 13 to the laminating mechanism 15. In Figure 1, for convenience, a configuration is shown in which both the first and second substrates 21 and 22 are heated by one substrate heating mechanism 14, but two or more substrate heating mechanisms 14 may be provided to heat the first and second substrates 21 and 22 independently. Furthermore, the substrate heating mechanism 14 may be omitted, and the substrates 21 and 22 may be laminated to the adhesive layer 20 without heating.

[0070] The laminating mechanism 15 laminates the first and second substrates 21 and 22 supplied from the dispensing mechanism 13 onto the thermoplastic resin composition (adhesive layer 20) extruded from the mold 12. The laminating mechanism 15 includes, for example, first and second rolls 35 and 36 as shown in Figure 2. The first roll 35 is a cast roll, on which the first and second substrates 21 and 22 are laminated onto the adhesive layer 20. The second roll 36 is a nip roll, positioned at a certain distance from the first roll 35, and can be used to press the first substrate 21, adhesive layer 20, and second substrate 22 supplied between the first roll 35 and the nip roll together. The first and second rolls 35 and 36 may both be metal rolls or rubber rolls with rubber wrapped around a metal core, but it is preferable to have one metal roll and the other rubber roll. By using a metal roll on one side and a rubber roll on the other, uneven pressing is eliminated, allowing for stable lamination of the substrates 21 and 22 onto the adhesive layer 20. Furthermore, the first and second rolls 35 and 36 may each have a temperature control mechanism, such as flowing a fluid like steam, oil, or water inside, or introducing a heater or electromagnetic induction. The first and second substrates 21 and 22 and the adhesive layer 20 may be heated by the temperature control mechanism. Having a temperature control mechanism makes it easier to adjust the temperature of the first and second substrates 21 and 22 and the adhesive layer 20 during lamination to a desired range.

[0071] In this embodiment, the first base material 21 supplied from the feeding mechanism 13 is supplied to the first roll 35 as shown in Figure 2, conveyed along the first roll 35, and supplied between the first and second rolls 35 and 36. The second base material 22 supplied from the feeding mechanism 13 is supplied to the second roll 36, conveyed along the second roll 36, and supplied between the first and second rolls 35 and 36. It is preferable that the first and second rolls 35 and 36 rotate in opposite directions while the first and second base materials 21 and 22 are being supplied.

[0072] Meanwhile, the thermoplastic resin composition (adhesive layer 20) extruded from the mold 12 and melted is supplied between the first and second rolls 35 and 36. Between the first and second rolls 35 and 36, the first substrate 21 and the second substrate 22 are laminated onto each of the supplied adhesive layer 20, respectively, to obtain a laminate 25. In this embodiment, the temperature R1 of the adhesive layer 20 when the first and second substrates 21 and 22 are laminated onto the adhesive layer 20 is preferably above the softening temperature of the adhesive layer 20. However, the temperature R1 is not particularly limited, but it is preferable to keep it below a certain level from the viewpoint of preventing the adhesive layer 20 from softening or melting more than necessary when it is laminated onto the first substrate 21 and the second substrate 22.

[0073] The first substrate 21 may have an uneven surface on the surface in contact with the adhesive layer 20. This may form an uneven surface on the surface of the adhesive layer 20 that is on the side of the first substrate 21. Alternatively, an uneven surface may be formed on the surface of the second substrate 22 that is in contact with the adhesive layer 20, thereby forming an uneven surface on the surface of the adhesive layer 20 that is on the side of the second substrate 22.

[0074] In the lamination mechanism 15, the laminate 25 obtained by laminating the first and second substrates 21 and 22 is sent to the annealing section 16. In the annealing section 16, the laminate 25 is maintained at a temperature above the softening temperature of the thermoplastic resin composition (adhesive layer 20) and annealed. The laminate 25 is then cooled by the cooling mechanism 17 and then wound into a roll in the winding mechanism 18 to obtain a roll body, which is a roll-shaped laminate. In the winding mechanism 18, the roll body is preferably wound around the outer circumference of a winding core. Here, in the annealing section 16, the laminate 25 may be kept warm or heated by the heating mechanism, or it may be slowly cooled in a room temperature environment. The cooling mechanism 17 is not particularly limited, but examples include a cooling roll and a cooling space. Furthermore, the winding mechanism 18 is not particularly limited, and a known winding machine may be used. The laminate 25 is annealed to promote stress relaxation, remove the strain generated in the adhesive layer 20 during extrusion, and prevent the adhesive layer 20 (resin film 50) from shrinking due to subsequent cooling. The width of the ends of the laminate 25 may be adjusted before it is wound up by the winding mechanism 18, and inspections may be performed as appropriate. The annealing section 16 and the cooling mechanism 17 may be omitted as appropriate.

[0075] It should be noted that the above manufacturing method is just one example, and the product can be manufactured using various other methods. For example, in the laminating mechanism 15 described above, the first and second base materials 21 and 22 are laminated on both sides of the adhesive layer 20 on a pair of rolls, but it is not necessary for the base materials 21 and 22 to be laminated on a pair of rolls. For example, two sets of rolls may be prepared, and one of the base materials, the first or second, may be laminated onto the adhesive layer between the rolls of the first set, and the other base material may be laminated onto the adhesive layer between the rolls of the second set.

[0076] Furthermore, although the above description shows the obtained laminate being wound up by the winding mechanism 18, the obtained laminate does not need to be wound up by the winding mechanism 18. In this case, the obtained laminate may be cooled by the cooling mechanism 17 and then cut or punched out to form individual sheets. Then, two or more of these individual sheets of laminate can be stacked to form a single sheet.

[0077] Furthermore, humidity control may be performed as appropriate. Humidity control may be performed by providing a humidity control section between the annealing section 16 and the cooling mechanism 17. For example, humidity control may be performed by passing the laminate through a space in an environment with a temperature of 50°C to 120°C, preferably 60°C to 100°C, and a humidity of, for example, 10% RH or higher, preferably 50% RH to 95% RH. In the present invention, since at least one of the first substrate and the second substrate has a high water vapor permeability at a temperature of 70°C and a humidity of 90% RH, the adhesive layer can be appropriately moistened to improve adhesive strength.

[0078] [Method for Manufacturing Adhesive Film] The method for manufacturing an adhesive film of the present invention includes the steps of: manufacturing a laminate by laminating a first substrate to one side of an adhesive layer containing a thermoplastic resin and laminating a second substrate to the other side of the adhesive layer; and peeling off at least one of the first and second substrates from the laminate. The first and second substrates are made of materials different from the adhesive layer, and the water vapor transmission rate of at least one of the first and second substrates at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２The adhesive strength is 1 / day or more. The adhesive layer obtained by peeling off at least one of the first and second substrates becomes the adhesive film. The manufacturing methods for the adhesive layer, the first substrate, the second substrate, and the laminate have already been explained in the section on the laminate, so the explanation of the manufacturing methods for the adhesive layer, the first substrate, and the laminate will be omitted. According to the manufacturing method for the adhesive film of the present invention, an adhesive film can be obtained that can suppress the decrease in adhesive strength of the adhesive layer due to the lamination of substrates. It is preferable to peel off both the first and second substrates from the laminate. It is preferable to peel off one of the first and second substrates before it is bonded to the adherend. The peeling off of the other substrate may be done after it is bonded to the adherend or before it is bonded to the adherend. If the peeling off of the substrate is done before it is bonded to the adherend, it is preferable to do so immediately before bonding.

[0079] [Method of Use of Laminate] The laminate of the present invention is not particularly limited, and it is preferable that the adhesive layer (adhesive film) be bonded to another adherend for use. The laminate of the present invention is preferable to be used by peeling off at least one of the substrates and then bonding the adhesive layer to the other adherend. In this case, both substrates may be peeled off before bonding the adhesive layer to the adherend, or one of the substrates may be bonded to the adherend while still laminated to the adhesive layer. When the first substrate is bonded to the adherend while still laminated to the adhesive layer, the first substrate may be peeled off from the adhesive layer after the adhesive film has been bonded to the adherend. Also, when the second substrate is bonded to the adherend while still laminated to the adhesive layer, the second substrate may be peeled off from the adhesive layer after the adhesive film has been bonded to the adherend.

[0080] The substrate to which the adhesive layer is bonded is not particularly limited, but examples include organic material substrates and inorganic material substrates. Examples of organic material substrates include organic resin plates and resin films. Organic resin plates are also called organic glass. Examples of organic glass are not particularly limited, but examples include polycarbonate plates and (meth)acrylic plates such as polymethyl methacrylate plates. The thickness of the organic glass and the inorganic glass described later (collectively referred to as glass members) is not particularly limited, but is preferably 0.1 mm or more, more preferably 1.0 mm or more, and also preferably 5.0 mm or less, and even more preferably 3.2 mm or less.

[0081] The resin film is not particularly limited, but examples include polyester resin films such as (meth)acrylic resin film, polycarbonate film, polyethylene terephthalate (PET) film, polyethylene naphthalate (PEN) film, polyolefin resin films such as polyethylene film, polypropylene film, cyclic polyolefin (COP) film, triacetylcellulose (TAC) film, polyethersulfone (PES) resin film, and polyimide resin film. Furthermore, the surface of the resin film may be provided with a surface layer, such as a hard coat layer made of (meth)acrylic resin or a coating layer containing a heat-shielding substance. The adhesive layer of the present invention may also be bonded to an adhesive layer made of the thermoplastic resin composition described above. Therefore, the adhesive layer of the present invention may use the adhesive layer of the present invention as the adherend. The thickness of the resin film is not particularly limited, but is preferably 30 μm or more and 2 mm or less, more preferably 40 μm or more and 1 mm or less, and even more preferably 50 μm or more and 500 μm or less. While materials that are relatively thick, have low flexibility, and are generally not bendable are called organic resin sheets, materials that are relatively thin and generally bendable are generally called resin films, these are not clearly distinguished from each other.

[0082] Inorganic glass is an example of an inorganic material substrate. Inorganic glass is not particularly limited, but examples include various glass sheets such as float glass, tempered glass, colored glass, polished glass, patterned glass, wired glass, reinforced glass, ultraviolet absorbing glass, infrared reflective glass, infrared absorbing glass, and green glass. Inorganic glass may be subjected to surface treatment, and a surface layer consisting of a coating layer containing a heat-shielding substance may be provided.

[0083] Furthermore, the laminate of the present invention is preferably used for electronic equipment applications. More specifically, the laminate of the present invention is preferably used for functional elements. The functional element is preferably electrically controllable. In that case, it is equipped with an electrical circuit, and its operation can be switched by the flow of current or by a change in the amount of current flowing. Specific examples of electrically controllable functional elements include electrically controllable films and electrically controllable flexible printed circuit boards. More specifically, examples include films or flexible printed circuit boards equipped with devices such as dimming elements, coils, antennas, piezoelectric elements, LED elements, batteries, sensors such as touch sensors, switches, integrated circuits such as memory, processors, and communication ICs, and display elements such as organic EL display elements and liquid crystal display elements. Furthermore, the functional element may be a glass panel on which these devices are mounted on a glass member, an image display panel in which a display element is incorporated into a glass member, or a touch panel in which a touch sensor is incorporated into a resin film or glass member. As a functional element, a dimming element equipped with a dimming element is preferred. Examples of dimming elements include polymer-dispersed liquid crystals (PDLCs), electrochromic (EC) devices, suspended particle devices (SPDs), electrophoretic devices, and guest-host liquid crystals (GHLCs). Functional elements that include display elements such as organic EL displays and liquid crystal displays are also preferred.

[0084] An electrically controllable film may include at least a base film and a device provided on the base film, but it may also be a film in which the device is placed between two base films. Examples of base films include polyester resin films such as polyethylene terephthalate and polyethylene naphthalate, acrylic resin films, cellulose derivative films such as triacetylcellulose (TAC), polyethersulfone (PES) resin films, and polyimide resin films. In addition, in an electrically controllable film, it is preferable to provide an electrode layer on the device-side surface of the base film. The electrode layer can be any conventionally known electrode material without particular limitations, but a transparent electrode layer is preferred.

[0085] The functional element is more preferably a dimmable film in which the device is a dimming element. An example of a dimmable film is one comprising two base films and a dimming element (dimming layer) disposed between the two base films. The functional element may not be electrically controlled. Specifically, examples include a heat-shielding film (heat-absorbing, reflective), a color film, a polarizing plate, an optical compensation plate, or a composite thereof. The thickness of the functional element is not particularly limited, but for example, it is about 20 μm to 2000 μm, preferably 100 μm to 1000 μm, and more preferably 200 μm to 800 μm. Note that the thickness of the functional element may change depending on the position, but if the thickness changes, it means the maximum thickness.

[0086] The laminate of the present invention is preferably used to bond two members together by placing the adhesive layer between them, and more preferably used as an interlayer for laminated glass, which is placed between two glass members to bond them together.

[0087] Furthermore, the adhesive layer of the present invention is also preferably used in image display devices, for example, for bonding together components constituting an image display device such as cover glass, touch panels, and image display panels. When the laminate of the present invention is used in a functional element, the adhesive layer may be used to bond the functional element to other components. Alternatively, a functional element such as a dimming element may be fitted into a frame of the adhesive layer, which has been molded into a frame shape to match the functional element, and then bonded to other components such as a resin film.

[0088] As described above, the water vapor transmission rate of at least one of the first and second substrates at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２ Since the humidity level is 1 / day or more, even though the first and second substrates are bonded together, humidity control is possible during storage, making it easier to increase the adhesive strength of the bonding layer when they are bonded together.

[0089] The present invention will be described in more detail by reference to examples, but the present invention is not limited in any way by these examples. The methods for measuring and evaluating each physical property in the present invention are as follows.

[0090] [Hydroxyl Group Amount in Polyvinyl Acetal Resin] The hydroxyl group amount in polyvinyl acetal resin is the value expressed as a percentage of the mole fraction obtained by dividing the amount of ethylene groups to which hydroxyl groups are attached by the total amount of ethylene groups in the main chain. The above hydroxyl group amount was calculated from the degree of acetalization [%] and degree of acetylation [%] measured by NMR using the formula: Hydroxyl group amount [%] = 100 - (Degree of acetalization [%] + Degree of acetylation [%]).

[0091] [Degree of Acetylation of Polyvinyl Acetal Resin] The degree of acetylation of polyvinyl acetal resin is the value expressed as a percentage of the mole fraction obtained by dividing the amount of ethylene groups to which acetyl groups are attached by the total amount of ethylene groups in the main chain. The above degree of acetylation was measured by NMR. The NMR measurement conditions were as follows: A nuclear magnetic resonance (NMR) spectrometer (Bruker, product name "AVANCE III HD") was used to perform 1H-NMR measurements using a 400 MHz spectrometer. PVB was dissolved in deuterated dimethyl sulfoxide (DMSO) to a concentration of 1% by mass. The horizontal axis represents the chemical shift in ppm, and the reference for the chemical shift was DMSO-d6 at 2.49 ppm.

[0092] [Degree of Acetalization of Polyvinyl Acetal Resin] The degree of acetalization of polyvinyl acetal resin was measured by NMR. The NMR measurement conditions were as follows: A nuclear magnetic resonance (NMR) spectrometer (Bruker, product name "AVANCE III HD") was used to perform 1H-NMR measurements using a 400 MHz spectrometer. PVB was dissolved in deuterated dimethyl sulfoxide (DMSO) to a concentration of 1 mass%. The horizontal axis represents the chemical shift in ppm, with DMSO-d6 set as the reference for the chemical shift at 2.49 ppm.

[0093] [Blocking properties of hydroxyl group-containing structural units] The blocking properties of hydroxyl group-containing structural units in polyvinyl acetal resin were determined by the following formula, using the peak intensity around 43.8 ppm, which originates from two structures indicating the randomness of hydroxyl groups as measured by NMR, and the peak intensity around 45.3 ppm, which indicates the degree of blocking of hydroxyl groups: Blocking properties of hydroxyl group-containing structural units = (Peak intensity around 45.3 ppm / (Peak intensity around 43.8 ppm, which originates from two structures)) The NMR measurement conditions were as follows: A nuclear magnetic resonance (NMR) spectrometer (Bruker, product name "AVANCE III HD") was used to perform 13C-NMR measurements using a 400 MHz spectrometer. PVB was dissolved in deuterated dimethyl sulfoxide (DMSO) to a concentration of 12% by mass. NMR measurements were performed using the inverse gate decoupling method at a temperature of 80°C. The horizontal axis represents the chemical shift in ppm, with DMSO-d6 set as the baseline for the chemical shift at 39.5 ppm.

[0094] [Water Vapor Permeability of Substrate] The water vapor permeability of the substrate was measured in accordance with JIS K7129. Specifically, a water vapor permeability meter (Lyssy, product name "L80-4000") was used to sandwich the sample into a standard sample card (product number "PN211113"), and the water vapor permeability was measured under the specified measurement temperature and humidity conditions. For measurement samples with high water vapor permeability, such as triacetylcellulose resin (TAC) film and polyamide resin (PA) film, aluminum tape with pre-cut openings (3M, product name "3M Aluminum Foil Tape 427") was attached to both sides of the sample to limit the permeable area during measurement. The opening area was 5 × 10 －３ I understand ２ However, when the substrate is PA, the opening area is 7.9 × 10 －５ I understand ２ When the substrate is TAC, the opening area is 2.0 × 10 －５ I understand ２ That's what I decided.

[0095] [Adhesion strength of substrate to adhesive layer] The laminate was cut to a width of 25 mm and a length of 300 mm, and the adhesive layer of the laminate was attached to a glass plate using double-sided tape. In accordance with JIS K 6854-2: 1999 (ISO 8510-2: 1990), a tensile testing machine (e.g., Instron 5965 universal material testing machine) was used as the measuring instrument. The sample substrate was held with the other end holding the glass, double-sided tape, and adhesive layer, and the substrate was peeled from the laminate attached to the glass plate in a 180° direction at a measurement temperature of 23°C and a tensile speed of 5 mm / sec. The adhesive strength (N / 25 mm) between the adhesive layer and the substrate at 23°C was measured. The peel length was set to 125 mm or more, and the average peel force over 100 mm excluding the first 25 mm was taken as the adhesive strength.

[0096] [Adjustment of Adhesion Strength] (1) Measurement of Initial Adhesion Strength (Adhesion Strength 1) Immediately after opening the aluminum bag containing the laminate, it was cut into strips 25 mm wide and 300 mm long. After peeling the substrate from the cut laminate to obtain the adhesive film, a glass plate (25 mm x 300 mm), adhesive film (25 mm x 300 mm), polyimide Kapton film (25 mm x 300 mm, thickness 50 μm, no release treatment on both sides), and glass plate 550 (25 mm x 300 mm) were stacked in order from the bottom to create a laminate. The obtained laminate was placed in a rubber bag and subjected to reduced pressure suction to remove air remaining between each layer, and then pre-bonded at 80°C to obtain a pre-compressed laminate. Next, the pre-compressed laminate was placed in an autoclave and compressed at 140°C and 1.3 MPa to create a laminate for peel strength measurement. Since the top glass plate does not adhere to the adhesive layer, the top glass plate was removed from the laminate to obtain a sample for measurement. The glass plate used was soda-lime glass manufactured by Central Glass Co., Ltd., size: 25 mm x 300 mm, thickness: 2.5 mm. The obtained sample for measurement was measured in accordance with JIS K6854-2:1999 (ISO8510-2:1990). A tensile testing machine (Instron Co., Ltd., Model 5965 universal material testing machine, or an equivalent) was used for the measurement. The edge of the portion of the sample that was not adhered to the bottom glass plate was grasped with one jig, and the bottom glass plate, which was the adherend, was grasped with the other jig. In this state, the sample was peeled in the 180° direction at a tensile speed of 100 mm / min, and the adhesive strength (N / 25 mm) between the interlayer filler and the glass surface at 23°C was measured. For convenience, the obtained adhesive strength is defined as adhesive strength 1. (2) The aluminum bag containing the laminate for measuring the standard adhesive strength (adhesion strength 2) was opened and cut into strips 25 mm wide and 300 mm long. After peeling the substrate from the cut laminate to obtain an adhesive film, the adhesive film was suspended and stored for 24 hours in an environment with a temperature of 22°C and a humidity of 23% RH. After that, the adhesive strength was measured using the same procedure as in (1) for measuring the initial adhesive strength. For convenience, the obtained adhesive strength will be referred to as adhesive strength 2. After that, it was checked whether the following formula (1) was satisfied and it was found to be 23%.20% ≤ |(adhesion strength 1 - adhesion strength 2) / adhesion strength 2| ≤ 25% (1) If the above formula (1) is not satisfied, the temperature and / or humidity is changed until the above formula (1) is satisfied, and adhesion strength 2 is measured again. (3) The aluminum bag containing the evaluation measurement laminate was opened and cut into three strips 25 mm wide and 300 mm long to obtain the laminate for evaluation criterion A, the laminate for evaluation criterion B, and the laminate for evaluation criterion C. The laminate for evaluation criterion A, the laminate for evaluation criterion B, and the laminate for evaluation criterion C were stored in an environment of 95°C and 95% RH for 1, 2, and 3 minutes, respectively. After that, the adhesion strength was measured using the same procedure as in (1) for measuring the initial adhesion strength. For convenience, the obtained adhesion strength is referred to as adhesion strength 3. It was evaluated whether adhesion strength 3 reached within ±10% of the standard adhesion strength (|(adhesion strength 3 - adhesion strength 2) / adhesion strength 2| is within 10%). (Evaluation Criteria) A: All laminates for evaluation criteria reached ±10% of the standard adhesive strength. B: Only the laminates for evaluation criteria B and C reached ±10% of the standard adhesive strength. C: Only the laminate for evaluation criterion C reached ±10% of the standard adhesive strength. D: None of the laminates for evaluation criteria reached ±10% of the standard adhesive strength.

[0097] The following materials were used in the examples and comparative examples.

[0098] The thermoplastic resins used in the examples and comparative examples were prepared as follows: (Polyvinyl butyral resin 1 (PVB1)) 1800 ml of deionized water and 200 g of polyvinyl alcohol (average degree of polymerization 1700, degree of saponification 99 mol%) were added to a reactor equipped with a stirring device, and heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, 30% hydrochloric acid was added to this solution as a catalyst to a hydrochloric acid concentration of 0.2 mass%, and the temperature was adjusted to 15°C. Then, n-butyraldehyde was added while stirring to a total of 10 mol%. After that, when n-butyraldehyde was added to a total of 70 mol%, white particulate polyvinyl butyral resin precipitated. Ten minutes after precipitation, 30% hydrochloric acid was added to a hydrochloric acid concentration of 1.8 mass%, and then the temperature was raised to 58°C and aged at a maturation temperature of 58°C for 2 hours. Next, the solution was cooled and neutralized, and then the polyvinyl butyral resin was washed with water and dried to obtain a resin (polyvinyl butyral resin 1 (PVB1), hydroxyl group content 30.3 mol%, degree of acetalization 68.5 mol%, degree of acetylation 1.2 mol%, blockability of constituent units having hydroxyl groups 0.32).

[0099] (Polyvinyl butyral resin 2 (PVB2)) In a reactor equipped with a stirring device, 1800 ml of deionized water and 200 g of polyvinyl alcohol (average degree of polymerization 1700, degree of saponification 99 mol%) were added and heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, 30% hydrochloric acid was added to this solution as a catalyst to a hydrochloric acid concentration of 0.2 mass%, and after adjusting the temperature to 15°C, n-butyraldehyde was added while stirring to a total of 10 mol%. After that, when n-butyraldehyde was added to a total of 68 mol%, white particulate polyvinyl butyral resin precipitated. Ten minutes after precipitation, 30% hydrochloric acid was added to a hydrochloric acid concentration of 1.8 mass%, and then the temperature was raised to 58°C and aged at a maturation temperature of 58°C for 2 hours. Next, the solution was cooled and neutralized, and then the polyvinyl butyral resin was washed with water and dried to obtain a resin (polyvinyl butyral resin 2 (PVB2), hydroxyl group content 32.9 mol%, degree of acetalization 66.3 mol%, degree of acetylation 0.8 mol%, blockability of constituent units having hydroxyl groups 0.35).

[0100] (Polyvinyl butyral resin 3 (PVB3)) In a reactor equipped with a stirring device, 1800 ml of deionized water and 200 g of polyvinyl alcohol (average degree of polymerization 1700, degree of saponification 99 mol%) were added and heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, 30% hydrochloric acid was added to this solution as a catalyst to a hydrochloric acid concentration of 0.2 mass%, and after adjusting the temperature to 15°C, n-butyraldehyde was added while stirring to a total of 10 mol%. After that, when n-butyraldehyde was added to a total of 71 mol%, white particulate polyvinyl butyral resin precipitated. Ten minutes after precipitation, 30% hydrochloric acid was added to a hydrochloric acid concentration of 1.8 mass%, and then the temperature was raised to 58°C and aged at a maturation temperature of 58°C for 2 hours. Next, the solution was cooled and neutralized, and then the polyvinyl butyral resin was washed with water and dried to obtain a resin (polyvinyl butyral resin 3 (PVB3), hydroxyl group content 30.0 mol%, degree of acetalization 69.2 mol%, degree of acetylation 0.8 mol%, blockability of constituent units having hydroxyl groups 0.32).

[0101] (Polyvinyl butyral resin 4 (PVB4)) In a reactor equipped with a stirring device, 1800 ml of deionized water and 200 g of polyvinyl alcohol (average degree of polymerization 1700, degree of saponification 99 mol%) were added and heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, 30% hydrochloric acid was added to this solution as a catalyst to a hydrochloric acid concentration of 0.2 mass%, and after adjusting the temperature to 15°C, n-butyraldehyde was added while stirring to a total of 10 mol%. After that, n-butyraldehyde was added to a total of 75 mol%, and white particulate polyvinyl butyral resin precipitated. Ten minutes after precipitation, 30% hydrochloric acid was added to a hydrochloric acid concentration of 1.8 mass%, and then the temperature was raised to 58°C and aged at a maturation temperature of 58°C for 2 hours. Next, the solution was cooled and neutralized, and then the polyvinyl butyral resin was washed with water and dried to obtain a resin (polyvinyl butyral resin 4 (PVB4), hydroxyl group content 26.8 mol%, degree of acetalization 72.4 mol%, degree of acetylation 0.8 mol%, blockability of constituent units having hydroxyl groups 0.26).

[0102] (Polyvinyl butyral resin 5 (PVB5)) In a reactor equipped with a stirring device, 1800 ml of deionized water and 200 g of polyvinyl alcohol (average degree of polymerization 1700, degree of saponification 99 mol%) were added and heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, 30% hydrochloric acid was added to this solution as a catalyst to a hydrochloric acid concentration of 0.2 mass%, and after adjusting the temperature to 15°C, n-butyraldehyde was added while stirring to a total of 10 mol%. After that, when n-butyraldehyde was added to a total of 65 mol%, white particulate polyvinyl butyral resin precipitated. Ten minutes after precipitation, 30% hydrochloric acid was added to a hydrochloric acid concentration of 1.8 mass%, and then the temperature was raised to 58°C and aged at a maturation temperature of 58°C for 2 hours. Next, the solution was cooled and neutralized, and then the polyvinyl butyral resin was washed with water and dried to obtain a resin (polyvinyl butyral resin 5 (PVB5), hydroxyl group content 35.1 mol%, degree of acetalization 64.1 mol%, degree of acetylation 0.8 mol%, blockability of constituent units having hydroxyl groups 0.36).

[0103] (Polyvinyl butyral resin 6 (PVB6)) In a reactor equipped with a stirring device, 1800 ml of deionized water and 200 g of polyvinyl alcohol (average degree of polymerization 1700, degree of saponification 99 mol%) were added and heated and dissolved while stirring to obtain a polyvinyl alcohol solution. Next, 30% hydrochloric acid was added to this solution as a catalyst to a hydrochloric acid concentration of 0.2 mass%, and after adjusting the temperature to 15°C, n-butyraldehyde was added while stirring to a total of 10 mol%. After that, when n-butyraldehyde was added to a total of 79 mol%, white particulate polyvinyl butyral resin precipitated. Ten minutes after precipitation, 30% hydrochloric acid was added to a hydrochloric acid concentration of 1.8 mass%, and then the temperature was raised to 58°C and aged at a maturation temperature of 58°C for 2 hours. Next, the solution was cooled and neutralized, and then the polyvinyl butyral resin was washed with water and dried to obtain a resin (polyvinyl butyral resin 6 (PVB6), hydroxyl group content 25.0 mol%, degree of acetalization 72.4 mol%, degree of acetylation 0.8 mol%, blockability of constituent units having hydroxyl groups 0.22).

[0104] Table 1 shows the amount of hydroxyl groups, degree of acetalization, degree of acetylation, and blockability of constituent units having hydroxyl groups for polyvinyl butyral resins 1 to 6 (PVB1 to 6).

[0105] The release substrates used in the examples and comparative examples were as follows: ・PET1: PET (polyethylene terephthalate) film, manufactured by Toyobo Co., Ltd., product name "E5000", thickness 75 μm ・PET2: PET (polyethylene terephthalate) film, manufactured by Toyobo Co., Ltd., product name "E5000", thickness 50 μm ・PET3: PET (polyethylene terephthalate) film, manufactured by Toyobo Co., Ltd., product name "Cosmopeel E7004", thickness 50 μm ・PEN: PEN (polyethylene naphthalate resin) film, manufactured by Toyobo Co., Ltd., product name "Teonex Q51 series", thickness 50 μm ・OPP: OPP (biaxially oriented polypropylene resin) film, manufactured by Toray Industries, Inc., product name "Trefan(R)", thickness 50 μm ・PMP: PMP (polymethylpentene resin) film, manufactured by Mitsui Chemicals, Inc., product name "Opulan(R) X-44B", thickness 50 μm - TAC: TAC (triacetylcellulose resin) film, manufactured by IPI, product name "CTAFilm50um SAB", thickness 50 μm - PA: PA (polyamide resin) film (nylon 6 resin film), manufactured by Toyobo, product name "Harden N1102", thickness 25 μm

[0106] (Example 1) A laminate was manufactured using the manufacturing apparatus 10 shown in Figure 1. Specifically, a resin composition was prepared by supplying 100 parts by mass of resin and 35 parts by mass of a plasticizer (triethylene glycol-di-2-ethylhexanoate: 3GO) to an extruder 11 and melt-kneading them together. The resin composition was then extruded from a mold 12 at 209°C. Meanwhile, the first and second substrates 21 and 22 were fed out from the first and second feeding mechanisms 31 and 32. In Example 1, PET1 was used as the first substrate 21 and the second substrate 22. The extruded resin composition (adhesive layer 20) was sandwiched between two heated substrates 21 and 22 in the manner shown in Figure 2 to produce a laminate with an adhesive layer thickness of 380 μm. When laminating the first and second substrates 21 and 22, the temperature of the cast roll 35 was set to 80°C and the temperature of the nip roll 36 was set to 40°C. The laminate was formed by laminating the first substrate, adhesive layer, and second substrate in that order, and the types of the first and second substrates in the laminate are as shown in Table 1. The laminate was wound into a roll using the winding mechanism 18 to form a roll-shaped laminate. The obtained laminate was unwound, cut to the size required for each test, and then stored for 168 hours at a temperature of 23°C and a humidity of 9% RH to conditioned the adhesive layer. After that, it was placed in an aluminum bag to protect it from the influence of atmospheric humidity. After exhausting as much air as possible from inside the aluminum bag, the opening of the aluminum bag was sealed.

[0107] (Example 2) PET2 was used as the first substrate 21 and the second substrate 22. Otherwise, a laminate was obtained in the same manner as in Example 1.

[0108] (Example 3) PET3 was used as the first substrate 21 and the second substrate 22. Otherwise, a laminate was obtained in the same manner as in Example 1.

[0109] (Example 4) A laminate was manufactured using the manufacturing apparatus shown in Figures 3 and 4. Specifically, a resin composition was prepared by supplying 100 parts by mass of thermoplastic resin and 35 parts by mass of a plasticizer (triethylene glycol-di-2-ethylhexanoate: 3GO) to an extruder 61 and melt-kneading them together, and the resin composition was extruded from a mold 62. The resin temperature at the mold exit was 210°C. The obtained adhesive layer was cooled by immersion in a water bath as shown in Figure 4, and then the obtained adhesive layer was wound up to form a wound body. The thickness of the adhesive layer was 380 μm. Subsequently, the laminate was laminated using the manufacturing apparatus shown in Figure 3. Specifically, the adhesive layer (resin film) was unwound from the wound body in a room temperature environment and heated at 80°C for 5 seconds in a resin layer heating mechanism 51 consisting of a heating roll. Furthermore, two substrates 21 and 22 were fed out from the first and second feeding mechanisms 31 and 32, and each substrate 21 and 22 was heated to 80°C in a substrate heating mechanism 14 consisting of a heating roll. PMP was used as the substrates 21 and 22. Next, the fed-out resin film (adhesive layer 20) was sandwiched between the two heated release substrates 21 and 22 in the manner shown in Figure 2 to produce a laminated sheet with an adhesive layer thickness of 380 μm. The temperature of the cast roll 35 and the nip roll 36 when laminating the first and second substrates 21 and 22 was set to 90°C. After that, the laminate was slowly cooled in an air-cooling tank until it reached room temperature, and then wound into a roll shape in the winding mechanism 18 to form a roll-shaped laminate. The obtained laminate was unwound, cut to the size required for each test, and then stored for 168 hours at a temperature of 22°C and a humidity of 9% RH to conditioned the adhesive layer. After that, it was stored in an aluminum bag to protect it from the influence of atmospheric humidity. Then, after exhausting as much air as possible from inside the aluminum bag, the opening of the aluminum bag was sealed.

[0110] (Example 5) TAC was used as the first substrate 21 and the second substrate 22. Otherwise, a laminate was obtained in the same manner as in Example 4.

[0111] (Example 6) PA was used as the first substrate 21 and the second substrate 22. Otherwise, a laminate was obtained in the same manner as in Example 4.

[0112] (Example 7) The thickness of the adhesive layer was set to 200 μm. Otherwise, the laminate was obtained in the same manner as in Example 2.

[0113] (Example 8) A laminate was obtained using PVB2 resin in the same manner as in Example 2.

[0114] (Example 9) A laminate was obtained using PVB3 resin in the same manner as in Example 2.

[0115] (Example 10) A laminate was obtained using PVB4 resin in the same manner as in Example 2.

[0116] (Example 11) A laminate was obtained using PVB5 resin in the same manner as in Example 2.

[0117] (Example 12) A laminate was obtained using PVB6 resin in the same manner as in Example 2.

[0118] (Comparative Example 1) PEN was used as the first substrate 21 and the second substrate 22. Otherwise, a laminate was obtained in the same manner as in Example 4.

[0119] (Comparative Example 2) OPP was used as the first substrate 21 and the second substrate 22. Otherwise, the laminate was obtained in the same manner as in Example 4.

[0120] Table 2 shows the evaluation results for Examples 1 to 12 and Comparative Examples 1 to 2.

[0121]

[0122] In each of the above embodiments, the water vapor transmission rate of at least one of the first and second substrates at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２ Since the value was 1 / day or more, the adhesive strength of the adhesive layer was high even when the first substrate and the second substrate were laminated. In contrast, in Comparative Examples 1 and 2, the water vapor transmission rate of both the first substrate and the second substrate at a temperature of 70°C and a humidity of 90% RH was 70 g / m². ２ Because it was smaller than / day, the adhesive strength of the adhesive layer when the first substrate and the second substrate were laminated was low.

[0123] 10 Manufacturing equipment 11 Extruder 12 Mold 13 Feed mechanism 14 Substrate heating mechanism 15 Laminating mechanism 16 Annealing section 17 Cooling mechanism 18 Winding mechanism 20 Adhesive layer 21, 22 Substrate 25 Laminate 31 First feed mechanism 32 Second feed mechanism 35 First roll 36 Second roll 41 Pinch roll 42, 43 Guide roll 50A Winding body 51 Resin layer heating mechanism 64 Cooling water tank 65 Guide roll

Claims

1. The apparatus comprises a first substrate, a second substrate, and an adhesive layer containing a thermoplastic resin provided between the first and second substrates, wherein the first and second substrates are made of materials different from the adhesive layer, and the water vapor transmission rate of at least one of the first and second substrates at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２ A laminate that is / day or larger.

2. The water vapor transmission rate of the first and second substrates at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２ The laminate according to claim 1, wherein the density is / day or greater.

3. The water vapor transmission rate of at least one of the first and second substrates at a temperature of 23°C and a humidity of 90% RH is 4 g / m². ２ The laminate according to claim 1 or 2, wherein the density is / day or greater.

4. The laminate according to any one of claims 1 to 3, wherein the thermoplastic resin is an ethylene-vinyl acetate copolymer or a polyvinyl acetal resin.

5. The laminate according to claim 4, wherein the blockability of the constituent units having hydroxyl groups in the polyvinyl acetal resin is 0.25 or more and 0.38 or less.

6. The laminate according to claim 4, wherein the amount of hydroxyl groups in the polyvinyl acetal resin is 26 mol% or more and 33 mol% or less.

7. The laminate according to any one of claims 1 to 6, wherein the adhesive layer has a multilayer structure of two or more layers.

8. The laminate according to any one of claims 1 to 7, wherein the resin constituting the first substrate and the second substrate is at least one resin selected from the group consisting of polyester resin, polymethylpentene resin, triacetylcellulose resin (TAC), and polyamide resin, and the thickness of the first substrate and the second substrate is 10 μm or more and 200 μm or less.

9. The laminate according to any one of claims 1 to 8, wherein at least one of the first substrate and the second substrate is provided with an adhesion strength adjusting layer on the surface facing the adhesive layer, and the thickness of the adhesion strength adjusting layer is 10 μm or less.

10. The laminate according to any one of claims 1 to 9, wherein the adhesive strength of at least one of the first substrate and the second substrate to the adhesive layer is 0.03 N / 25 mm or more.

11. A roll body comprising a winding core and a laminate according to any one of claims 1 to 10 wound around the outer circumference of the winding core.

12. A single-sheet body comprising two or more laminates according to any one of claims 1 to 10.

13. A process for manufacturing a laminate comprising: a step of bonding a first substrate to one side of an adhesive layer containing a thermoplastic resin, and a step of bonding a second substrate to the other side of the adhesive layer; and a step of peeling off at least one of the first and second substrates from the laminate, wherein the first and second substrates are made of materials different from the adhesive layer, and the water vapor transmission rate of at least one of the first and second substrates at a temperature of 70°C and a humidity of 90% RH is 50 g / m². ２ A method for manufacturing adhesive films that has a lifespan of at least one day.

Images