JP6998704B2 - Transparent resin laminate - Google Patents

Description

The present invention relates to a transparent resin laminate provided with a transparent resin sheet and a composite interlayer film.

Acrylic resin has high transparency and is excellent in weather resistance, scratch resistance and rigidity, so that it is being studied as a substitute for glass. However, acrylic resin is a resin that exhibits brittle fracture behavior, is inferior in impact resistance, and may cause human damage because the debris when cracked is sharp. Therefore, it is difficult to use acrylic resin as it is as a substitute for glass.

As a method for improving the above-mentioned problems, a method of adding a rubber component to improve the impact resistance of acrylic is generally known. With this method, it is possible to improve the impact resistance as the amount of the rubber component increases, but on the other hand, the elastic modulus tends to decrease. The vehicle glazing material, which is one of the main uses as a substitute for glass, is desired to have high rigidity from the viewpoint of deflection due to wind pressure during traveling. Therefore, the improvement of impact resistance by adding the rubber component remains a problem in the case of the glazing material.

As another method for improving the above-mentioned problems, a method is known in which a transparent interlayer film is laminated between acrylic resins to prevent scattering of debris when the acrylic resin is broken. For example, Patent Documents 1 to 3 propose that a transparent interlayer film containing PVB, TPU, EVA, etc. is laminated between transparent resin sheets made of acrylic or polycarbonate.

JP-A-59-78852 Special Table 2009-541099 JP-A-2017-114028

However, in the configuration of Patent Document 1, the plasticizer added in the PVB layer, which is an interlayer film, bleeds out, the adhesive force with the acrylic resin sheet is lowered, and the obtained laminate is whitened. There was a problem.

Further, in the configurations of Patent Documents 2 and 3, since the rigidity of the interlayer films TPU and EVA is low, there is a problem that the rigidity of the obtained laminate is also low.

The present invention has been made in view of the above circumstances, and provides a transparent resin laminate having excellent impact resistance and shatterproofness while maintaining the excellent transparency, weather resistance and rigidity inherent in acrylic resin. With the goal.

The present inventor has conducted extensive research, and by providing a composite interlayer film containing an ionomer interlayer film and an ethylene copolymer interlayer film, and laminating the adhesive strength between the transparent resin sheet and the composite interlayer film within a specific range. , It was found that the anti-scattering property was good, and the present invention was completed based on this finding. That is, the present invention provides the following laminates [1] to [4].
[1]; A composite interlayer film sandwiched between at least two transparent resin sheets and the transparent resin sheet is included, and the composite interlayer film contains at least one ionomer intermediate film and at least one ethylene copolymer interlayer film. A transparent resin laminate having an adhesive strength between the transparent resin sheet and the composite interlayer film of 25 N / 25 mm or more and 50 N / 25 mm or less.
[2]; The transparent resin laminate according to [1], wherein the ethylene copolymer is an ethylene vinyl acetate copolymer.
[3]; The transparent resin laminate according to [1], wherein the ethylene copolymer is a styrene-ethylene block copolymer.
[4]; The transparent resin laminate according to any one of [1] to [3], wherein the transparent resin sheet is an acrylic resin sheet.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a transparent resin laminate having good weather resistance, high transparency, high rigidity, light weight, and excellent impact resistance and shatterproofness.

It is a schematic cross-sectional view of the transparent resin laminate of one Embodiment which concerns on this invention. It is a schematic sectional drawing of the transparent resin laminated body of another embodiment which concerns on this invention.

1A Transparent resin sheet 1B Transparent resin sheet 2A Ethylene copolymer intermediate film 2B Ethylene copolymer intermediate film 2C Ethylene copolymer intermediate film 2D Ethylene copolymer intermediate film 3 Ionomer intermediate film 3A Ionomer intermediate film 3B Ionomer intermediate film 3C Ionomer Intermediate film 10X Composite interlayer film 10Y Composite interlayer film 11X Transparent resin laminate 11Y Transparent resin laminate

Hereinafter, the present invention will be described in detail. In the present specification, any numerical range A to B indicates a numerical range of A or more and B or less.

"Transparent resin laminate"
The laminate of the present invention includes a transparent resin sheet, at least a composite interlayer film containing an ionomer interlayer film and an ethylene copolymer interlayer film, and the transparent resin sheet and the composite interlayer film are in close contact with each other. It is preferable that at least one transparent resin sheet is in close contact with the ethylene copolymer interlayer, the outermost layer of the composite interlayer is the ethylene copolymer interlayer, and all the transparent resin sheets are in close contact with the ethylene copolymer interlayer. It is more preferable to do so. The laminate of the present invention has good transparency, rigidity, sound insulation, weather resistance, impact resistance, and shatterproofness, and can be made lighter than glass. Therefore, vehicle glazing, building material window materials, and display windows. It can be suitably used as a protective plate or the like.

FIG. 1 shows a schematic cross-sectional view of the laminated body of one embodiment according to the present invention.
In the figure, reference numeral 10X is an interlayer film laminate, reference numeral 11X is a transparent resin laminate of the present invention, reference numerals 1A and 1B are transparent resin sheets, reference numerals 2A and 2B are ethylene copolymer intermediate films, and reference numeral 3 is an ionomer interlayer film. Each is shown.

The laminated body 11X of the illustrated example is a laminated body having a five-layer structure composed of a two-layer transparent resin sheet and a three-layer composite interlayer film.

The laminated body of the present invention is not limited to the five-layer structure. The laminate of the present invention may contain any other layer.

FIG. 2 shows a schematic cross-sectional view of the transparent resin laminate of another embodiment according to the present invention.
In the figure, reference numeral 10Y indicates a composite interlayer film, reference numeral 11Y indicates a transparent resin laminate of the present invention, reference numerals 2A to 2D indicate an ethylene copolymer intermediate film, and reference numerals 3A to 3C indicate an ionomer interlayer film.

The laminated body 11Y of the illustrated example is a laminated body having a nine-layer structure composed of a two-layer transparent resin sheet and a seven-layer composite interlayer film.

The transparent resin laminate of the present invention is excellent in anti-scattering property by laminating the adhesive strength between the transparent resin sheet and the composite interlayer film including the ethylene copolymer interlayer film within a specific range. The ethylene copolymer interlayer film has a relatively low rigidity (elastic modulus), and therefore the rigidity of the obtained laminate tends to be relatively low. The present inventor can suppress a decrease in the rigidity of the transparent resin laminate by using a composite interlayer film in which an ionomer interlayer film is laminated in addition to the ethylene copolymer interlayer film, and further impact resistance and shatterproof prevention. It was found that the sex was good. As a result, when the transparent resin laminate of the present invention is used as a vehicle glazing material, which is one of the main uses as a substitute for glass, it is possible to provide a laminate in which deflection due to wind pressure during traveling is suppressed.

The adhesive strength between the transparent resin sheet and the composite interlayer film in the transparent resin laminate of the present invention is preferably 25 N / 25 mm or more and 50 N / 25 mm or less, and more preferably 30 N / 25 mm or more and 45 N / 25 mm or less. , 35N / 25mm or more and 40N / 25mm or less is more preferable. When the adhesive strength between the transparent resin sheet and the composite interlayer film is 25 N / 25 mm or more and 50 N / 25 mm or less, interface peeling does not occur between the transparent resin sheet and the composite interlayer film in a high temperature and high humidity environment, and impact resistance is achieved. When the laminate is broken in the test, the fragments of the transparent resin sheet can be held by adhesion with the composite interlayer film and are not scattered, which is preferable. The two outer surfaces of the composite interlayer are preferably ethylene copolymer interlayers, and in this case, the adhesive strength is the adhesive strength between the transparent resin sheet and the ethylene copolymer interlayer.

The transparent resin laminate has at least two transparent resin sheets, preferably two to four, more preferably two or three, and even more preferably two. When there are three transparent resin sheets, the configuration is (transparent resin sheet)-(composite interlayer film)-(transparent resin sheet)-(composite interlayer film)-(transparent resin sheet), and when there are four transparent resin sheets, The composition is (transparent resin sheet)-(composite interlayer film)-(transparent resin sheet)-(composite interlayer film)-(transparent resin sheet)-(composite interlayer film)-(transparent resin sheet).

As a method for setting the adhesive strength to 25 N / 25 mm or more, the adhesive strength can also be changed by adjusting the molding time at the time of molding. Further, as will be described later, the adhesive strength between the composite interlayer film and the transparent resin sheet is obtained by adding silane coupling or the like to the interlayer film, or applying surface treatment to at least one of the adhesive surfaces by an atmospheric pressure plasma treatment device. Can be adjusted.

Various atmospheric pressure plasma devices can be used for the plasma irradiation. For example, a device capable of generating low-temperature plasma by performing intermittent discharge while passing an inert gas having a pressure near atmospheric pressure between electrodes covered with a dielectric is preferable, and any device can be used. Various variants can be selected according to the purpose of use and the like.

As the discharge gas used when generating the atmospheric pressure plasma, any gas of nitrogen, oxygen, hydrogen, carbon dioxide, helium, and argon, or a mixed gas of two or more of these can be used. It is preferable to use a rare gas such as argon or helium which is an inert gas, or a nitrogen gas, and a rare gas such as argon or helium is particularly preferable.

The transparent resin laminate of the present invention can be produced by a conventionally known method, and examples thereof include a heat press, an autoclave, and a co-extrusion bonding method. The bonding method using a hot press is to insert a composite interlayer film that has been made into a sheet in advance between the transparent resin sheets and temporarily fix it, then heat the laminated composite film to soften the composite interlayer film and then pressurize it with a press. It is integrated with. The method of bonding by autoclave is to insert a composite interlayer film that has been made into a sheet in advance between transparent resin sheets and temporarily fix it, then enclose the overlapped material in a vacuum bag and reduce the pressure with a vacuum pump, or this overlapped method. Is preheated with hot air, an infrared heater, etc., and then pressurized using a nip roll. After the prelamination process, the pressure and heating are performed with an autoclave to integrate the particles. In the coextrusion method, the resin used as the raw material for the composite interlayer film and the transparent resin sheet is heated and melt-plasticized in an extruder and laminated inside the T-die or before the inflow of the T-die to integrate them.

In order to facilitate the removal of air bubbles that have entered between the laminates, it is preferable to create a vacuum between the press plates of a hot press or to bond by an autoclave using a vacuum bag.

[Transparent resin sheet]
Examples of the transparent resin used in the transparent resin sheet according to the present invention include acrylic resin, polycarbonate resin, acrylonitrile styrene copolymer resin, acrylonitrile butadiene styrene copolymer resin, polyester resin, fluororesin, polyvinyl chloride resin, and chlorinated polychloride. Examples thereof include vinyl resin, polypropylene resin, cycloolefin polymer resin, cycloolefin copolymer resin, polystyrene resin, polysulfone resin, epoxy resin, phenol resin, unsaturated polyester resin, polyimide resin, etc., and these may be used alone or in combination of two. A transparent resin sheet can be obtained by using the above in combination. The transparent resin is preferably an acrylic resin from the viewpoint of transparency, rigidity and weather resistance.

The acrylic resin is polymethyl methacrylate (PMMA), which is a homopolymer of methyl methacrylate (MMA), or a copolymer of MMA and one or more other monomers. One type or two or more types of acrylic resin can be used.

The content of the MMA unit in the acrylic resin is not particularly limited, and since the transparent resin sheet is excellent in heat resistance and scratch resistance, it is preferably 60% by mass or more, more preferably 80% by mass or more, still more preferably 90. It is by mass or more, particularly preferably 99% by mass or more, and most preferably 100% by mass.

The MMA content in the acrylic resin is purified by reprecipitating the acrylic resin in methanol, and then pyrolysis and separation of volatile components are performed using pyrolysis gas chromatography to obtain MMA and a copolymer component. It can be calculated from the ratio of the peak areas of.

The acrylic resin can contain structural units other than MMA units. Structural units other than the MMA unit include methyl acrylate (MA), ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, and 2-butyl acrylate. Acrylic acid alkyl ester such as ethyl hexyl; Acrylic acid aryl ester such as phenyl acrylate; Acrylic acid cycloalkyl ester such as cyclohexyl acrylate and norbornenyl acrylate; Aromatic vinyl compounds such as styrene and α-methyl styrene; A structural unit derived from a vinyl-based monomer having only one polymerizable carbon-carbon double bond in one molecule such as unsaturated dicarboxylic acid such as maleic acid; acrylamide; methacrylic acid; acrylic nitrile; methacrylic nitrile; Can be mentioned. MA or the like is preferable from the viewpoint of availability.

The content of the structural unit other than the MMA unit in the acrylic resin is preferably 40% by mass or less, more preferably 20% by mass or less, particularly preferably 10% by mass or less, most preferably 1% or less, and even 0%. good.

The acrylic resin is obtained by polymerizing one or more kinds of monomers containing MMA. When a plurality of types of monomers are used in the polymerization, usually, the plurality of types of monomers are mixed to prepare a monomer mixture, which is then subjected to the polymerization. The polymerization method is not particularly limited, and radical polymerization, anionic polymerization and the like are preferable from the viewpoint of productivity and heat resistance.

From the viewpoint of heat resistance and moldability, the acrylic resin preferably has a triplet-displayed syndiotacticity (rr) (hereinafter, also referred to as “rr ratio”) of 50 to 85%. From the viewpoint of heat resistance, the lower limit of the rr ratio is more preferably 53%, further preferably 55%, particularly preferably 58%, and most preferably 60%. From the viewpoint of moldability, the upper limit of the rr ratio is more preferably 77%, particularly preferably 65%.

The rr ratio is a ratio in which two chains (double element, diad) possessed by a chain of three consecutive structural units (triplet, triad) are both racemo (denoted as rr). In the chain of structural units (double element, diad) in the polymer molecule, those having the same configuration are referred to as meso, and the opposite ones are referred to as racemo, which are referred to as m and r, respectively.

The rr ratio of the acrylic resin is 0.6 to 0.95 ppm when ¹ H-NMR spectrum is measured in deuterated chloroform at 30 ° C. and tetramethylsilane (TMS) is 0 ppm from the spectrum. The area (X) of the region of 0.6 to 1.35 ppm and the area (Y) of the region of 0.6 to 1.35 ppm can be measured and calculated by the formula: (X / Y) × 100.

The acrylic resin preferably has a glass transition temperature (Tg) of 110 ° C. or higher, more preferably 120 ° C. or higher, and even more preferably 130 ° C. or higher. When the Tg is 110 ° C. or higher, the hard resin sheet has excellent heat resistance.

The glass transition temperature in the present specification is a temperature measured by a differential scanning calorimeter at a heating rate of 10 ° C./min and calculated by the midpoint method.

The method for producing the transparent resin sheet according to the present invention is not particularly limited, and the transparent resin sheet of the present invention is obtained by molding by, for example, a melt molding method such as a T-die method, a compression molding method, an injection molding method, or a solution casting method. be able to. Further, the transparent resin sheet of the present invention can be obtained by simultaneously performing a reaction molding method such as a cell cast polymerization method, that is, a polymerization reaction and molding of a monomer mixture. Among these molding methods, the T-die method, the inflation method, the injection molding method, and the cell cast polymerization method are preferable from the viewpoints of high productivity, cost, and the like.

The surface of the transparent resin sheet according to the present invention is coated with an acrylic, silicone, or inorganic (particle) -based hard coat for the purpose of improving abrasion resistance, scratch resistance, chemical resistance, weather resistance, anti-fog resistance, and the like. A surface protective layer such as may be provided.

The surface protective layer can usually be formed by applying a fluid curable composition composed of a monomer, an oligomer, a resin, or the like to the surface of a transparent resin sheet and curing the surface protective layer. These curable compositions are, for example, thermosetting compositions that are cured by heat and energy ray-curable compositions that are cured by energy rays such as electron beams, radiation, and ultraviolet rays. Further, the surface protective layer may be formed by a vapor deposition method such as chemical vapor deposition or physical vapor deposition. Further, the surface protective layer may be formed in advance on the base film by these methods, and then the surface protective layer may be formed by a transfer method in which the surface protective layer is transferred to the surface layer of the transparent resin sheet via the adhesive layer.

Further, a resin film or the like may be attached to further enhance the shatterproof performance.

A primer layer may be provided on the surface of the transparent resin sheet according to the present invention for the purpose of controlling the adhesiveness with the interlayer film. As the primer layer, a resin composition having a high chemical affinity with the resin component of the interlayer film or a resin composition portion having a reactive functional group can be used. Further, the polar group may be introduced into the sheet surface by corona treatment, plasma treatment or the like.

The transparent resin sheet according to the present invention includes an ultraviolet absorber for improving weather resistance, a light stabilizer, an antioxidant, a plasticizer for improving moldability, a heat stabilizer, other heat ray absorbers, and coloring. It may contain an agent, a light diffusing agent, a flame retardant, an antistatic agent and the like.

Inorganic compounds such as silica fine particles, glass flakes, glass fibers, crystalline or solid silicate compounds can be added to the transparent resin sheet to improve dimensional stability. These compounds may be added at the time of polymerization of the composition of the transparent resin sheet or at the time of molding.

The thickness, shape, and size of the transparent resin sheet may be appropriately selected depending on the intended use, and are not particularly limited. Further, since the transparent resin sheet has hygroscopicity, the adsorbed water may become bubbles during heating, which may impair the transparency and appearance of the laminate of the present invention. Therefore, it is desirable to perform a drying treatment to remove the moisture in the sheet before adhering the transparent resin sheet and the interlayer film. The drying treatment conditions may be appropriately set, but it is preferable to carry out the drying treatment at 80 to 125 ° C. for about 1 to 10 hours.

The thickness of the transparent resin sheet can be 1 to 20 mm, preferably 2 to 10 mm.

[Composite interlayer]
The composite interlayer film of the transparent resin laminate of the present invention includes an ionomer interlayer film and an ethylene copolymer interlayer film. Each interlayer film has an ultraviolet absorber, a light stabilizer, an antioxidant, a heat stabilizer, a heat ray absorber, a colorant, a flame retardant, a decorative layer, a light diffuser, and an antistatic agent for improving weather resistance. It may contain an inhibitor or the like.

The composite interlayer film of the present invention contains at least one ionomer interlayer film and at least one ethylene copolymer interlayer film. Since it is preferable that the ethylene copolymer interlayer film is in close contact with the transparent resin sheet, it is preferable to include at least two of them.

The composite interlayer film of the transparent resin laminate of the present invention may contain an ionomer interlayer film and an ethylene copolymer interlayer film, as well as a resin interlayer film having other structural units, if necessary. The resin having other structural units is not particularly limited as long as it is a resin that exhibits adhesiveness by heating and melting, and can be appropriately selected depending on the intended purpose. For example, it is preferably at least one selected from plasticized polyvinyl butyral, thermoplastic polyurethane, cyclic polyolefin and the like.

In the present specification, the ionomer interlayer film contains more than 50% by mass of ionomer, preferably 60% or more, more preferably 70% or more, still more preferably 80% or more, particularly preferably 90% or more, and most preferably 95%. With the above, the ionomer may be 100%. Examples of the component other than the ionomer contained in the ionomer interlayer include plasticized polyvinyl butyral, thermoplastic polyurethane, cyclic polyolefin, ethylene copolymer and the like.

In the present specification, the ethylene copolymer interlayer has an ethylene copolymer of more than 50% by mass, preferably 60% or more, more preferably 70% or more, still more preferably 80% or more, and particularly preferably 90% or more. Most preferably, it is 95% or more, and the ethylene copolymer may be 100%. Examples of the components other than the ethylene copolymer contained in the ethylene copolymer interlayer include plasticized polyvinyl butyral, thermoplastic polyurethane, cyclic polyolefin, ionomer copolymer and the like.

For example, the composite interlayer film of the present invention has three layers of (100% ethylene copolymer interlayer film)-(5% ethylene copolymer + 95% ionomer interlayer film)-(100% ethylene copolymer interlayer film) by mass. It may be a configuration.

The resin having the other structural units exhibits transparency and viscoelasticity due to entanglement of molecular chains even after adhesion as compared with a general adhesive that solidifies after adhesion. Therefore, the laminated body in which the interlayer film made of these transparent resins is sandwiched and integrated exhibits high transparency and excellent anti-scattering performance.

The interlayer film according to the present invention, particularly the interlayer film on the outer surface, may contain an adhesive force adjusting agent such as a silane coupling agent for the purpose of controlling the adhesiveness with the transparent resin sheet and other layers. Further, a polar group may be introduced into the surface of the interlayer film by corona treatment, plasma treatment or the like.

The ionomer according to the present invention is not particularly limited, but has a structural unit derived from ethylene and a structural unit derived from α, β-unsaturated carboxylic acid, and at least a part of the α, β-unsaturated carboxylic acid is contained. Examples include resins neutralized by metal ions. Examples of the metal ion include sodium ion, zinc ion and the like. In the ethylene / α, β-unsaturated carboxylic acid copolymer as the base polymer, the content ratio of the structural unit of α, β-unsaturated carboxylic acid is preferably 2% by mass or more, preferably 5% by mass or more. It is more preferable to have. The content ratio of the constituent units of α, β-unsaturated carboxylic acid is preferably 30% by mass or less, and more preferably 20% by mass or less. In the present invention, from the viewpoint of easy availability, an ionomer of an ethylene / acrylic acid copolymer and an ionomer of an ethylene / methacrylic acid copolymer are preferable. As an example of the ethylene-based ionomer, a sodium ionomer of an ethylene / acrylic acid copolymer and a sodium ionomer of an ethylene / methacrylic acid copolymer can be mentioned as particularly preferable examples.

Examples of the α, β-unsaturated carboxylic acid constituting the ionomer according to the present invention include acrylic acid, methacrylic acid, maleic acid, monomethyl maleate, monoethyl maleate, maleic anhydride and the like, but acrylic acid or methacrylic acid. Acids are particularly preferred.

The ethylene copolymer according to the present invention includes an ethylene-α-olefin copolymer; an ethylene-alkyl (meth) acrylate copolymer; an ethylene-vinyl acetate copolymer (EVA); a styrene-ethylene copolymer; and a polystyrene. -Poly (ethylene-butylene) -polystyrene block copolymer, styrene-ethylene block copolymer such as polystyrene-poly (ethylene-propylene) -polystyrene block copolymer and the like.

The content of the ethylene structural unit in the ethylene copolymer according to the present invention is preferably in the range of 8 to 80% by mass, more preferably in the range of 10 to 78% by mass, and 12 to 76% by mass. It is more preferably in the range. If the ethylene structural unit is less than 8% by mass, the impact resistance of the laminate may be insufficient, and if the ethylene structural unit exceeds 80% by mass, the adhesiveness between the transparent resin sheet and the interlayer film tends to decrease.

The ethylene-α-olefin copolymer is a copolymer containing several mol% or more of α-olefin, and the α-olefin is propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-. 1-Penten and the like can be mentioned.

Examples of the ethylene-alkyl (meth) acrylate copolymer include an ethylene-methyl acrylate copolymer, an ethylene-methyl methacrylate copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-ethyl methacrylate copolymer, and an ethylene-butyl acrylate. Examples thereof include copolymers, ethylene-butyl methacrylate copolymers, ethylene-hexyl acrylate copolymers, ethylene-hexyl methacrylate copolymers, ethylene-lauryl acrylate copolymers, and ethylene-lauryl methacrylate copolymers. Of these, ethylene-methylmethacrylate copolymers are preferably used.

As the ethylene-vinyl acetate copolymer, those having a vinyl acetate structural unit content of 20% by mass or more and 40% by mass or less are preferably used, and those having a content of 22% by mass or more and 38% by mass or less are more preferable. Those having a mass% or more and 36% by mass or less are more preferably used. If the vinyl acetate structural unit is less than 20% by mass, the adhesiveness between the transparent resin sheet and other layers and the interlayer film tends to decrease, and if it exceeds 40% by mass, the impact resistance of the laminate may be insufficient.

As the styrene-ethylene block copolymer, a polymer obtained by hydrogenating a part or all of a styrene-butadiene-styrene block copolymer and a styrene-isoprene-styrene block copolymer is preferable. Specifically, a styrene-ethylene-butylene-styrene block copolymer (SEBS) and a styrene-isoprene-styrene block copolymer resin obtained by hydrogenating the butadiene portion of the styrene-butadiene-styrene block copolymer resin. It is obtained by hydrogenating the styrene-ethylene / propylene-styrene block copolymer (SEPS) obtained by hydrogenating the isoprene portion of the above, and hydrogenating the butadiene portion of the styrene polymer block and the random copolymer block of styrene and butadiene. Examples thereof include a block polymer resin, a block polymer resin obtained by hydrogenating the isoprene portion of a random copolymer block of a styrene polymer block and styrene and isoprene, and the like. The styrene may be an alkyl substituted styrene such as α-methylstyrene.
Examples of commercially available hydrogenated products (SEBS) of XYX type block copolymers of styrene and 1,3-butadiene include Clayton G manufactured by Clayton Co., Ltd. and Tough Tech manufactured by Asahi Kasei Co., Ltd. Further, among the copolymers of styrene and 1,3-butadiene, those having high randomness are generally abbreviated as HSBR, and examples of commercially available products thereof include Dynaron manufactured by JSR Corporation. Examples of commercially available hydrogenated products (SEPS) of XYX type block copolymers of styrene and isoprene include Kuraray Co., Ltd. Hybler and Septon. These block copolymers may be XY type diblock copolymers and include XY type diblock copolymers and XYX type triblock copolymers. It may be a composition.

The composite interlayer film according to the present invention has at least two interlayer films including an ionomer intermediate film and an ethylene copolymer intermediate film. Further, the A layer / B layer / A layer and the A layer / B layer / A layer / B layer in which the ionomer intermediate film layer (B) is laminated between at least two ethylene copolymer intermediate film layers (A). , A layer / B layer / A layer / B layer / A layer may be used. Among the above, it is preferable to have a laminated structure in which the B layer is laminated between at least two A layers. Further, the A layer constitutes at least one layer, preferably two layers, of the outermost layer.

Further, one or more layers other than the A layer and the B layer (referred to as the C layer) may be included, for example, A layer / B layer / C layer / A layer, A layer / B layer / A layer /. C layer, A layer / C layer / B layer / C layer / A layer, A layer / C layer / B layer / A layer / C layer, A layer / B layer / C layer / A layer / C layer, C layer / A layer / B layer / A layer / C layer, C layer / A layer / B layer / C layer / A layer / C layer, C layer / A layer / C layer / B layer / C layer / A layer / C A laminated structure such as a layer may be used. The resin constituting the C layer is preferably at least one selected from, for example, plasticized polyvinyl butyral, thermoplastic polyurethane, and cyclic polyolefin. Further, in the above laminated structure, the components in the C layer may be the same or different. This also applies to the components in the A layer or the B layer. Among the above, it is preferable to have a laminated structure in which the B layer is laminated between at least two A layers. Further, it is preferable that the A layer constitutes at least one layer of the outermost layer.

The thickness of the composite interlayer can be 0.5 to 5 mm, preferably 1 to 2 mm. The total thickness of the A layer can be 0.05 to 1 mm, preferably 0.1 to 0.5 mm. The total thickness of the B layer can be 0.4 to 3 mm, preferably 0.8 to 2 mm.

The method for producing the composite interlayer film according to the present invention is not particularly limited, and for example, a T-die method (lamination method, coextrusion method, etc.), coextrusion method, compression molding method, vacuum forming method, injection molding method (insert method, two). A composite interlayer can be formed by molding by a melt molding method such as a color method, a pressing method, a core back method, a sandwich method, etc., or a solution casting method.

Hereinafter, examples and comparative examples according to the present invention will be described.

[Evaluation items and evaluation methods]
The evaluation items and evaluation methods are as follows.

(Adhesive strength)
When the end of the intermediate layer laminated with the transparent resin sheet was peeled off, fixed with a gripping jig using "Autograph AG-1S" manufactured by Shimadzu Corporation, and peeled off at a test speed of 200 mm / min in the 180 ° direction. The load was measured. The width of the interlayer film was 25 mm.

(rigidity)
A transparent resin sheet and a test piece obtained by cutting each interlayer film into strips having a width of 10 mm and a length of 150 mm were prepared. The tensile elastic modulus of this test piece was measured at 23 ° C. using a universal testing machine RTC-1310A manufactured by Orientec Co., Ltd. by a method according to ASTM D 882: 2012. The ratio of the tensile elastic modulus of the composite interlayer film to the transparent resin sheet (E (composite interlayer film) / E (transparent resin sheet)) was determined. (The tensile elastic modulus of the composite interlayer film is referred to as E (composite interlayer film), and the tensile elastic modulus of the transparent resin sheet is referred to as E (transparent resin sheet).)
"○" when E (composite interlayer film) / E (transparent resin sheet) is 0.03 or more, and "x" when E (composite interlayer film) / E (transparent resin sheet) is smaller than 0.03. And said.

(Weatherability)
Using the Suga Test Instruments Sunshine Weather Meter S80 in accordance with JIS B7753 (2007), irradiate with a sunshine carbon arc (4 pairs of ultra long life carbon) light source with a discharge voltage of 50V and a discharge current of 60A. The surface was sprayed (rained) for 12 minutes per hour, and the transparent resin laminate was irradiated for 5000 hours under the conditions of a black panel temperature of 63 ° C. and a relative humidity of 50%. The glass filter used was A type.

After the irradiation test, the presence or absence of bubbles and peeling in the transparent resin laminate was confirmed, and the case where bubbles and peeling occurred was marked with "x", and the case where no bubbles and peeling occurred was marked with "○".

(Impact resistance)
A transparent laminate having a length of 1000 × 2000 mm fixed with a four-sided frame was installed in a direction perpendicular to the ground, and its short side was fixed to a support column using bolts. When a 300 kg steel ball was dropped from a height of 95 cm by a pendulum and collided with the central part of the sample, the state of destruction of the sample was observed. For the load, bolts were attached to the parts that collide with the sample so that the stress was concentrated. In other words, the sample was destroyed from the contact point with the bolt. The case where the sample debris did not scatter 1 m or more from the fixed portion of the transparent resin laminate was evaluated as “◯”, and the case where the sample debris scattered 1 m or more was evaluated as “x”.

(Example 1)
EVA film (length 1000 x width 2000 x thickness 0.15 mm, Mercen G7055) and length 1000 x width 2000 x thickness 1.0 mm ionomer film (DuPont, CenturyGlas (R) Interlayer) Was laminated in the order of EVA / ionomer / EVA to prepare an interlayer film, and then dried at 80 ° C. of length 1000 × width 2000 × thickness 5 mm for 24 hours with two methacrylic resin transparent sheets (comoglass manufactured by Kuraray Co., Ltd.). A laminate having a structure of methacrylic resin / EVA / ionomer / EVA / methacrylic resin was prepared by sandwiching the film.

Next, the laminate was sandwiched between two glass plates (length 1000 x width 2000 x thickness 5 mm), transferred into a microwave irradiation device, vacuum-sucked, and the entire surface of the laminate was covered and crimped with a diaphragm rubber sheet. .. Next, microwaves were irradiated with an output of 0 to 100 W, the output was adjusted so that the side surface temperature of the methacrylic resin sheet in the laminated body was 70 ° C., and the pressure was 0.5 MPa for 30 minutes while being held at 70 ° C. The transparent resin laminate of the present invention was obtained by heating under pressure under the above conditions and adhering while removing air bubbles existing on the interface between the methacrylic resin sheet and the EVA layer. The obtained transparent resin laminate was evaluated for adhesive strength, rigidity, weather resistance, and impact resistance. The test results are shown in Table 1.

(Example 2)
50 parts by mass of a styrene-ethylene block copolymer (Kurare Co., Ltd., Hybler 7311F) and 50 parts by mass (Kurare Co., Ltd., Hybler 7125F) were supplied to the hopper of a 65 mmφ vent type single-screw extruder. Extruded in a molten state at a cylinder temperature of 140 to 230 ° C., introduced into a T-die set at 210 ° C., and the extruded product is niped by two embossed rolls set at 15 ° C. to form a film. By extrusion molding, a film made of a styrene-ethylene block copolymer having a length of 1000 × width of 2000 × thickness of 150 μm was produced.

A transparent resin laminate was obtained in the same manner as in Example 1 except that a film made of the styrene-ethylene block copolymer was used instead of the EVA film as the interlayer film. The obtained transparent resin laminate was evaluated for adhesive strength, rigidity, weather resistance, and impact resistance. The test results are shown in Table 1.

(Comparative Example 1)
A transparent resin laminate was obtained in the same manner as in Example 1 except that an EVA film (length 1000 × width 2000 × thickness 400 μm) was used as the interlayer film. The obtained transparent resin laminate was evaluated for adhesive strength, rigidity, weather resistance, and impact resistance. The test results are shown in Table 1.

(Comparative Example 2)
A transparent resin laminate was obtained in the same manner as in Example 1 except that a 1.0 mm thick TPU film (Highgres TEND50601 manufactured by Seadam Co., Ltd.) was used instead of the ionomer film as the interlayer film. The obtained transparent resin laminate was evaluated for adhesive strength, rigidity, weather resistance, and impact resistance. The test results are shown in Table 1.

(Comparative Example 3)
A transparent resin laminate was obtained in the same manner as in Example 1 except that an EMMA film having a thickness of 1.0 mm (TA270717-171, manufactured by Sanbic Co., Ltd.) was used instead of the ionomer film as the interlayer film. The obtained transparent resin laminate was evaluated for adhesive strength, rigidity, weather resistance, and impact resistance. The test results are shown in Table 1.

(Comparative Example 4)
A transparent resin laminate was obtained in the same manner as in Example 1 except that a PVB film having a thickness of 1.0 mm (Trosifol Clear, manufactured by Kuraray Co., Ltd.) was used instead of the ionomer film as the interlayer film. The obtained transparent resin laminate was evaluated for adhesive strength, rigidity, weather resistance, and impact resistance. The test results are shown in Table 1.

The transparent laminate of the present invention (Examples 1 and 2) has a specific adhesive strength, and is excellent in rigidity, weather resistance, and impact resistance.

On the other hand, the transparent laminate in which the EVA layer alone (Comparative Example 1) or TPU, EMAA, or PVB was used instead of the ionomer as the interlayer film (Comparative Examples 2 to 4) is the transparent laminate of the present invention (Example). Compared with 1 and 2), the rigidity and weather resistance are greatly reduced.

The transparent laminate of the present invention has good impact resistance and anti-scattering properties, and has the characteristics of high rigidity, and is suitable for use in vehicle glazing and the like.

Claims (2)

The composite interlayer contains at least two transparent resin sheets and a composite interlayer sandwiched between the transparent resin sheets, wherein the composite interlayer contains at least one ionomer interlayer and at least two ethylene copolymer interlayers, and is an ethylene copolymer. The interlayer film and the transparent resin sheet are in close contact with each other, and the adhesive strength between the transparent resin sheet and the composite interlayer film is 25 N / 25 mm or more and 50 N / 25 mm or less . A transparent resin laminate that is a polymer . The transparent resin laminate according to claim 1, wherein the transparent resin sheet is an acrylic resin sheet.

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