TW201808638A - Resin laminate, display device and polarizer - Google Patents

Abstract

Provided is a resin laminate which is suitably used in a display device and is resistant to warpage. The present invention provides a resin laminate having at least an intermediate layer (A) and thermoplastic resin layers (B) and (C) present on both sides of the intermediate layer (A). The intermediate layer (A) contains 10 to 90% by mass of a (meth) acrylic resin and 90 to 10% by mass of a vinylidene fluoride resin based on the total resin contained in the intermediate layer (A), and the weight average molecular weight (Mw) of the (meth) acrylic resin is 100,000 to 300,000, wherein the thermoplastic resin layers (B) and (C) satisfy the following relationship. [Delta] L=|LB-LC| ≤ 20 [mu] m [Delta] [lambda] BC=|[Delta] [lambda] B- [Delta] [lambda] C| ≤ 0.19*10<SP>-4</SP> [Delta] T=|TB-TC| ≤ 4 DEG C [In the formula, LB and LC each represent the average values of film thicknesses of the thermoplastic resin layers (B) and (C), and [Delta] [lambda] B and [Delta] [lambda] C are respectively represented by the following formulas. [Delta] [lambda] B=|[lambda] 'B- [lambda] B| [Delta] [lambda] C=|[lambda] 'C- [lambda] C| In the above formula, [lambda] 'B and [lambda] 'C respectively represent the birefringences (I) measured for the thermoplastic resin layers (B) and (C) in the resin laminate, and [lambda] B and [lambda] C respectively reprecsent the birefringences (II) measured for the thermoplastic resin layers (B) and (C) in the resin laminate after an annealing treatment at a temperature lower than the Vicat softening temperature of the resin layers (B) and (C) by 25 DEG C for 4 hours, and TB and TC respectively represent Vicat softening temperatures of the thermoplastic resin layers (B) and (C).].

Description

Resin laminate, display device and polarizing plate

The present invention relates to a resin laminated body suitable for use in, for example, a display device, a display device containing the resin laminated body, and a resin laminated body with the resin laminated body laminated with the resin laminated body and polarizing plate.

In recent years, the number of people with touch screens in display devices such as smart phones, portable game consoles, audio players, and tablet terminals is increasing. The surface of such a display device generally uses a glass sheet, but from the viewpoint of weight reduction and processability of the display device, development of a plastic sheet as a substitute for a glass sheet is underway. For example, Patent Document 1 has disclosed a transparent sheet containing a methacrylic resin and a vinylidene fluoride resin as a plastic sheet instead of a glass sheet.

[Prior technical literature] [Patent Literature]

Patent Document 1: Japanese Patent Application Laid-Open No. 2013-244604.

The display device is used in various environments due to its high versatility. If a display device containing a plastic sheet is used in a severe environment such as high temperature and high humidity, the resin will swell due to expansion and contraction of the resin. In recent years, thinner display devices have been required, and warping has become a greater problem. An object of the present invention is to provide a resin laminate suitable for a display device and less prone to warping.

In order to solve the above-mentioned problems, the present inventors have reviewed the resin laminate suitable for a display device in detail, and completed the present invention.

That is, the present invention includes the following preferred aspects.

[1] A resin laminate having at least an intermediate layer (A) and thermoplastic resin layers (B) and (C) that are respectively present on both sides of the intermediate layer (A); Containing all resins, the intermediate layer (A) contains 10 to 90% by mass of (meth) acrylic resin and 90 to 10% by mass of vinylidene fluoride resin. The weight average molecular weight (Mw) of the (meth) acrylic resin ) Is 100,000 to 300,000; the thermoplastic resin layers (B) and (C) satisfy the following relationship: △ L = ｜ L _B -L _C ｜ ≦ 20 μm

△ λ _BC = ｜ △ λ _B- △ λ _C ｜ ≦ 0.19 × 10 ^-4

△ T = ｜ T _B -T _C ｜ ≦ 4 ℃

[In the formula, L _B and L _C respectively represent the average film thickness of the thermoplastic resin layers (B) and (C), and Δλ _B and Δλ _C are expressed by the following formulas, respectively, Δλ _B = ｜ λ ' _B -λ _B ｜

△ λ _C = ｜ λ ' _C -λ _C ｜

In the above formula, λ ' _B and λ' _C respectively indicate the birefringence (I) measured for the thermoplastic resin layers (B) and (C) in the resin laminate, and λ _B and λ _C are respectively expressed in the specific thermoplastic resin layer ( B) and (C) After annealing at a temperature lower than 25 ° C for 4 hours, the birefringences (II), T _B, and T _B of the thermoplastic resin layers (B) and (C) in the resin laminate were measured. T _C represents the Feika softening temperature of the thermoplastic resin layers (B) and (C), respectively].

[2] The resin laminate according to the above [1], wherein the intermediate layer (A) contains 35 to 45% by mass of a (meth) acrylic resin and a total resin contained in the intermediate layer (A); 65 to 55 mass% of vinylidene fluoride resin.

[3] The resin laminate according to the above [1] or [2], wherein the content of the alkali metal in the intermediate layer (A) is 50 ppm or less based on the total resin contained in the intermediate layer (A).

[4] The resin laminate according to any one of the above [1] to [3], wherein the (meth) acrylic resin is the following (a1) and / or (a2); (a1) methyl methacrylate A homopolymer of an ester; (a2) 50 to 99.9% by mass of a structural unit derived from methyl methacrylate and 0.1 to 50% by mass of a structural unit derived from the following formula with respect to the total structural unit constituting the polymer; (1) a copolymer of at least one structural unit of the (meth) acrylate shown; [Wherein, R ₁ represents a hydrogen atom or a methyl group, R ₁ is R ₂ represents an alkyl group having 1 to 8 carbon atoms of hydrogen atom, ₂ carbon atoms, represents alkyl of 2-8 R R ₁ is a methyl group].

[5] The resin laminate according to any one of the above [1] to [4], wherein the vinylidene fluoride resin is polyvinylidene fluoride.

[6] The resin laminate according to any one of the above [1] to [5], wherein the melt mass flow rate of the vinylidene fluoride resin is measured under conditions of a load of 3.8 kg and a temperature of 230 ° C. 0.1 to 40 g / 10 minutes.

[7] The resin laminate according to any one of the above [1] to [6], wherein the average film thickness of the resin laminate is 100 to 2000 μm, and the films of the thermoplastic resin layers (B) and (C) The average thickness is 10 to 200 μm, respectively.

[8] The resin laminate according to any one of the above [1] to [7], in which the Fica softening temperatures of the thermoplastic resins contained in the thermoplastic resin layers (B) and (C) are 100 to 160 ° C, respectively .

[9] The resin laminate according to any one of the above [1] to [8], wherein the thermoplastic resin layers (B) and (C) are (meth) acrylic resin layers or polycarbonate resin layers.

[10] The resin laminate according to any one of the above [1] to [9], wherein the thermoplastic resin layers (B) and (C) are polycarbonate resin layers, and It contains all resins and contains 0.005 to 2.0% by mass of ultraviolet absorber.

[11] The resin laminate according to any one of the above [1] to [9], wherein the thermoplastic resin layers (B) and (C) contain 50 masses with respect to the entire resin contained in each thermoplastic resin layer. % (Meth) acrylic resin.

[12] The resin laminate according to [11], wherein the weight average molecular weight of the (meth) acrylic resin contained in the thermoplastic resin layers (B) and (C) is 50,000 to 300,000.

[13] A display device comprising the resin laminate according to any one of [1] to [12].

[14] A polarizing plate with a resin laminate, which is obtained by laminating the resin laminate and the polarizing plate according to any one of [1] to [12].

[15] A display device including the polarizing plate with a resin laminate according to [14].

The resin laminate of the present invention is less likely to warp even when used in environments such as high temperature and high humidity, and is suitable for use in display devices and the like.

1‧‧‧Single-screw extruder (extrusion of melt of resin composition B)

2‧‧‧Single-screw extruder (extrusion of melt of resin composition A)

3‧‧‧Single-screw extruder (extrusion of melt of resin composition C)

4‧‧‧feeding port

5‧‧‧Multi-manifold mould

6‧‧‧ film-like molten resin

7‧‧‧The first cooling roller

8‧‧‧ 2nd cooling roller

9‧‧‧3rd cooling roller

10‧‧‧Resin laminate

10A‧‧‧Intermediate Level (A)

10B‧‧‧Thermoplastic resin layer (B)

10C‧‧‧Thermoplastic resin layer (C)

11‧‧‧ polarizing plate

12‧‧‧ Optical Adhesive Layer

13‧‧‧LCD cell

14‧‧‧ Liquid crystal display device

Fig. 1 is a schematic diagram of a manufacturing apparatus of a resin laminate of the present invention used in the embodiment.

FIG. 2 is a schematic cross-sectional view showing a preferred form of a liquid crystal display device including the resin laminate of the present invention.

The resin laminated system of the present invention has at least an intermediate layer (A) and thermoplastic resin layers (B) and (C) that are respectively present on both sides of the intermediate layer (A). In other words, the resin laminated body of this invention has a structure which laminated | stacked at least the thermoplastic resin layer (B) / intermediate layer (A) / thermoplastic resin layer (C) in this order.

The intermediate layer (A) contains 10 to 90% by mass of a (meth) acrylic resin and 90 to 10% by mass of a vinylidene fluoride resin with respect to the entire resin contained in the intermediate layer (A). When the amount of the (meth) acrylic resin is lower than the above lower limit, sufficient transparency cannot be obtained, and the amount of the (meth) acrylic resin is higher than the upper limit. When the upper limit is mentioned, a sufficient dielectric constant cannot be obtained. When the amount of the vinylidene fluoride resin is below the above-mentioned lower limit, a sufficient dielectric constant cannot be obtained, and when the amount of the vinylidene fluoride resin is above the above-mentioned upper limit, durability and sufficient transparency cannot be obtained.

From the viewpoint of easily improving the dielectric constant and improving the transparency of the resin laminate, the intermediate layer (A) preferably contains 30 to 60% by mass of the (methyl group) with respect to the entire resin contained in the intermediate layer (A). ) Acrylic resin and 70 to 40 mass% of vinylidene fluoride resin, more preferably 35 to 45 mass% of (meth) acrylic resin and 65 to 55 mass% of vinylidene fluoride resin, and more preferably 37 to 45% by mass of (meth) acrylic resin and 63 to 55% by mass of vinylidene fluoride resin, particularly preferred is 38 to 45% by mass of (meth) acrylic resin and 62 to 55% by mass of second The fluoroethylene resin is preferably a (meth) acrylic resin containing from 38 to 43% by mass and a vinylidene fluoride resin from 62 to 57% by mass.

Examples of the (meth) acrylic resin contained in the intermediate layer (A) of the resin laminate of the present invention include homopolymers of (meth) acrylic monomers such as (meth) acrylate and (meth) acrylonitrile, Copolymers of two or more (meth) acrylic monomers, copolymers of (meth) acrylic monomers and monomers other than (meth) acrylic monomers, and the like. In this specification, the term "(meth) acrylic acid" means "acrylic acid" or "methacrylic acid".

The (meth) acrylic resin is preferably a methacrylic resin from the viewpoint of easily improving the hardness, weather resistance, and transparency of the resin laminate. The methacrylic resin is a polymer of monomers mainly composed of methacrylate (also known as alkyl methacrylate). For example, a homopolymer of methacrylate (also known as polyalkyl methacrylate) ), 2 or more types of methacrylate A copolymer, a copolymer of 50% by mass or more of a methacrylate and a monomer other than 50% by mass of a methacrylate, and the like. From the viewpoint of easily improving optical characteristics and weather resistance, the copolymer of methacrylate and monomers other than methacrylate is preferably 70% by mass or more of methacrylate and A copolymer of 30% by mass or less of other monomers is more preferably a copolymer of 90% by mass or more of methacrylate and 10% by mass or less of other monomers.

Examples of the monomer other than the methacrylate include an acrylate and a monofunctional monomer containing one polymerizable carbon-carbon double bond in the molecule.

Examples of the monofunctional monomer include styrene monomers such as styrene, α-methylstyrene, and vinyl toluene; cyanide olefins such as acrylonitrile and methacrylonitrile; acrylic acid; methacrylic acid; maleic anhydride; N- Replace maleimidine and so on.

From the viewpoint of heat resistance, the (meth) acrylic resin can be copolymerized with N-substituted maleimide, such as phenylmaleimide, cyclohexylmaleimide, and methylmaleimide, It is also possible to introduce a lactone ring structure, a glutaric anhydride structure, or a glutarimide structure into a molecular chain (also referred to as a main skeleton or a main chain in a polymer).

From the viewpoint of easily improving the hardness, weather resistance, and transparency of the resin laminate, the (meth) acrylic resin is preferably the following (a1) and / or (a2): (a1) methyl methacrylate The homopolymer of the ester contains (a2) 50 to 99.9% by mass, preferably 70.0 to 99.8% by mass, and more preferably 80.0 to 99.7% by mass relative to the total structural unit constituting the copolymer. The amount of the structural unit derived from methyl methacrylate and the content of 0.1 to 50% by mass, preferably 0.2 to 30% by mass, and more preferably 0.3 to 20% by mass are derived from the following formula (1) A copolymer of at least one structural unit of (meth) acrylate. Here, the content of each structural unit can be calculated by analyzing the obtained polymer by thermal decomposition gas chromatography and measuring the peak area corresponding to each monomer.

[Wherein, R ₁ represents a hydrogen atom or a methyl group, R ₁ is R ₂ represents an alkyl group having 1 to 8 carbon atoms of hydrogen atom, ₂ carbon atoms, represents alkyl of 2-8 R R ₁ is a methyl group].

In formula (1), R ₁ represents a hydrogen atom or a methyl group, when R ₁ is a hydrogen atom, R ₂ represents an alkyl group having 1 to 8 carbon atoms, and when R ₁ is a methyl group, R ₂ represents an alkyl group having 2 to 8 carbon atoms. . Examples of the alkyl group having 2 to 8 carbon atoms include ethyl, propyl, isopropyl, butyl, second butyl, third butyl, pentyl, hexyl, heptyl, octyl and the like. From the viewpoint of heat resistance, R _{2 is} preferably an alkyl group having 2 to 4 carbon atoms, and more preferably an ethyl group.

The weight average molecular weight (hereinafter referred to as Mw) of the (meth) acrylic resin contained in the intermediate layer (A) is 100,000 to 300,000. If Mw is lower than the lower limit described above, the transparency when exposed to a high temperature and high humidity environment is insufficient. If Mw is higher than the upper limit described above, the film-forming properties when producing a resin laminate cannot be obtained. From the viewpoint of easily improving the transparency when exposed to a high temperature and high humidity environment, the Mw of the (meth) acrylic resin is preferably 120,000 or more, and more preferably 150,000 or more. From the viewpoint of the film-forming property when manufacturing a resin laminate The Mw of the (meth) acrylic resin is preferably 250,000 or less, and more preferably 200,000 or less. The weight average molecular weight was measured by a colloidal permeation chromatography (GPC) method.

The (meth) acrylic resin is measured under the conditions of a load of 3.8 kg and 230 ° C, and usually has a melt mass flow rate (hereinafter referred to as MFR) of 0.1 to 20 g / 10 minutes, preferably 0.2 to 5 g / 10 minutes, and more preferably 0.5 to 3 g / 10 minutes. If the MFR is below the above upper limit, the strength of the obtained film can be increased, so it is preferable, and from the viewpoint of the film-forming property of the resin laminate, it is preferably above the above lower limit. MFR can be measured according to the method specified in JIS K 7210: 1999 "Test methods for the melt mass flow rate (MFR) and melt volume flow rate (MVR) of plastics-thermoplastics". This JIS stipulates that poly (methyl methacrylate) -based materials are measured under conditions of a temperature of 230 ° C and a load of 3.80 kg (37.3 N).

From the viewpoint of heat resistance, the (meth) acrylic resin preferably has a Ficca softening temperature (hereinafter referred to as VST) of 90 ° C or higher, more preferably 100 ° C or higher, and still more preferably 102 ° C or higher. The upper limit of VST is not particularly limited, but it is usually 150 ° C or lower. VST can be measured according to JIS K 7206: 1999 and the B50 method described therein. VST can be adjusted to the above range by adjusting the type of monomer and its ratio.

The (meth) acrylic resin system can be prepared by polymerizing the monomers by a known method such as suspension polymerization or block polymerization. At this time, MFR, Mw, VST, etc. can be adjusted to a better range by adding an appropriate chain transfer agent. As a chain transfer agent, a suitable commercial item can be used. The amount of the chain transfer agent to be added may be appropriately determined according to the type of monomer, its ratio, and required characteristics.

Examples of the vinylidene fluoride resin contained in the intermediate layer (A) of the resin laminate of the present invention include homopolymers of vinylidene fluoride and copolymers of vinylidene fluoride and other monomers. From the viewpoint of easily improving the transparency of the obtained resin laminate, the vinylidene fluoride resin is preferably composed of trifluoroethylene, tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, perfluoroalkyl vinyl ether, and ethylene. A copolymer of at least one monomer and vinylidene fluoride, and / or a homopolymer of polyvinylidene fluoride (polyvinylidene fluoride) selected by the formed group, more preferably polyvinylidene fluoride.

The weight average molecular weight (Mw) of the vinylidene fluoride resin contained in the intermediate layer (A) is preferably 100,000 to 500,000, more preferably 150,000 to 450,000, still more preferably 200,000 to 450,000, and particularly preferably 350,000 to 450,000. If Mw is above the lower limit, it is preferable that the resin laminate of the present invention is easily exposed to a high temperature and high humidity environment (for example, 60 ° C. and a relative humidity of 90%) to improve the transparency of the resin laminate. Moreover, if Mw is below the said upper limit, since it is easy to improve the film-forming property of a resin laminated body, it is preferable. The weight average molecular weight was measured by a colloidal permeation chromatography (GPC) method.

The vinylidene fluoride resin is measured under the conditions of a load of 3.8 kg and 230 ° C, and preferably has a melt mass flow rate (MFR) of 0.1 to 40 g / 10 minutes, more preferably 0.1 to 30 g / 10 minutes, and more preferably It is 0.1 to 25 g / 10 minutes. The MFR is more preferably 0.2 g / 10 minutes or more, and still more preferably 0.5 g / 10 minutes or more. The MFR is more preferably 20 g / 10 minutes or less, still more preferably 5 g / 10 minutes or less, and particularly preferably 2 g / 10 minutes or less. If the MFR is equal to or less than the above upper limit, it is easy to suppress a decrease in transparency when the resin laminate is used for a long period of time, so it is preferable. If MFR is more than the said lower limit, since the film-forming property of a resin laminated body is easy to improve, it is preferable. MFR can be according to JIS K 7210: 1999 "Plastic-thermoplastic plastic melt mass flow rate (MFR) and melt volume flow rate (MVR) test method" specified in the method.

The vinylidene fluoride resin is industrially produced by a suspension polymerization method or an emulsion polymerization method. The suspension polymerization method uses water as a medium and uses a dispersant to disperse a monomer as droplets in the medium, and polymerizes an organic peroxide dissolved in the monomer as a polymerization initiator to obtain 100. To 300 μm granular polymer. Compared with the emulsified polymer, the suspension polymer is simpler in manufacturing steps and has superior powder handling properties, and does not contain an alkali metal-containing emulsifier or salting-out agent such as the emulsified polymer, so it is preferable.

A commercially available vinylidene fluoride resin can be used. Examples of preferred commercial products include "KF polymer (registered trademark) T # 1300, T # 1100, T # 1000, T # 850, W # 850, W # 1000, W # 1100, and W" of Kureha Co., Ltd. # 1300 "," SOLEF (registered trademark) 6012, 6010, and 6008 "manufactured by Solvay.

The intermediate layer (A) may further contain another resin different from a (meth) acrylic resin and a vinylidene fluoride resin. When other resins are contained, the type is not particularly limited as long as it does not significantly impair the transparency of the resin laminate. From the viewpoint of the hardness and weather resistance of the resin laminate, the amount of other resins is preferably 15% by mass or less, more preferably 10% by mass or less, and more preferably relative to the total resin contained in the intermediate layer (A). It is 5 mass% or less. Other resins include, for example, polycarbonate resin, polyamide resin, acrylonitrile / styrene copolymer, methyl methacrylate / styrene copolymer, polyethylene terephthalate, and the like. The intermediate layer (A) may further contain other resins. From the viewpoint of transparency, the amount of other resins is preferably 1% by mass or less. The intermediate layer (A) The resin contained is more preferably only (meth) acrylic resin and vinylidene fluoride resin.

The content of the alkali metal in the intermediate layer (A) is preferably 50 ppm or less, more preferably 30 ppm or less, still more preferably 10 ppm or less, and particularly preferably 1 ppm or less with respect to the total resin contained in the intermediate layer (A). If the content of the alkali metal in the intermediate layer (A) is equal to or less than the above-mentioned upper limit, it is easy to suppress a decrease in transparency when the resin laminate is used for a long period of time in a high-temperature and high-humidity environment. The lower limit of the content of the alkali metal in the intermediate layer (A) is 0, and from the viewpoint of easily suppressing the decrease in the transparency of the resin laminate, it is extremely preferable that it is substantially not contained. Here, the (meth) acrylic resin and / or vinylidene fluoride resin contained in the intermediate layer (A) contains trace emulsifiers and the like used in the production process. Therefore, the intermediate layer (A) contains alkali metals such as sodium and potassium derived from the residual emulsifier, for example, at least 0.05 ppm. In particular, when the (meth) acrylic resin and / or vinylidene fluoride resin contained in the intermediate layer (A) are obtained by emulsion polymerization, the amount of emulsifier remaining in the resin increases, and the alkali metal in the intermediate layer (A) Its content has also increased. From the viewpoint of easily suppressing the decrease in transparency of the resin laminate, it is preferable to use a resin having a small alkali metal content as the (meth) acrylic resin and vinylidene fluoride resin contained in the intermediate layer (A).

In order to make the content of the alkali metal in the resin within the above range, the amount of the compound containing the alkali metal can be reduced during the polymerization of the resin, or the washing step after the polymerization can be increased to remove the compound containing the alkali metal. The content of the alkali metal can be obtained, for example, by inductively coupled plasma mass spectrometry (ICP / MS). Inductively coupled plasma mass spectrometry can be used, for example, to dissolve the measured sample pellets by a high-temperature ash melting method, a high-temperature ash acid dissolution method, or Ca-added ash acid. Method, combustion absorption method, low-temperature ashing acid dissolving method and other suitable methods to ash the sample, dissolve it in acid, dilute the solution, and determine the content of alkali metal by inductively coupled plasma mass spectrometry.

The resin laminate of the present invention has at least thermoplastic resin layers (B) and (C) existing on both sides of the intermediate layer (A). The thermoplastic resin layer (B) and the thermoplastic resin layer (C) may be the same layer or different layers.

The thermoplastic resin layers (B) and (C) contain at least one thermoplastic resin. From the viewpoint of easily improving molding processability, the thermoplastic resin layers (B) and (C) preferably contain a thermoplastic resin of 60% by mass or more, and more preferably 70% by mass, with respect to the entire resin contained in each thermoplastic resin layer. The above is more preferably 80% by mass or more. The upper limit of the amount of the thermoplastic resin is 100% by mass. Examples of the thermoplastic resin include (meth) acrylic resin, polycarbonate resin, and cycloolefin resin. From the viewpoint of easily improving the adhesion between the thermoplastic resin layers (B) and (C) and the intermediate layer (A), the thermoplastic resin is preferably a (meth) acrylic resin or a polycarbonate resin. The thermoplastic resin layers (B) and (C) may contain the same thermoplastic resin or different thermoplastic resins. The thermoplastic resin layers (B) and (C) preferably contain the same thermoplastic resin from the viewpoint of easily suppressing warpage of the resin laminate.

From the viewpoint of the heat resistance of the resin laminate, the thermoplastic resin contained in the thermoplastic resin layers (B) and (C) is preferably measured in accordance with JIS K 7206: 1999, and preferably has a Ficca softening temperature of 100 to 160 ° C. The temperature is preferably 102 to 155 ° C, and more preferably 102 to 152 ° C. Here, when the thermoplastic resin layer contains one type of thermoplastic resin, the above-mentioned Ficca softening temperature is the Ficca softening temperature of the resin, and the thermoplastic resin layer contains two or more types of thermoplastic resins. In this case, the above-mentioned Ficca softening temperature is the Ficca softening temperature of the plurality of thermoplastic resin mixtures.

For the purpose of improving the strength and elasticity of the thermoplastic resin layer, the thermoplastic resin layers (B) and (C) may further contain resins other than the thermoplastic resin (for example, thermosetting resins such as fillers and resin particles). At this time, the amount of other resins is preferably 40% by mass or less, more preferably 30% by mass or less, and still more preferably 20% by mass or less with respect to the total resin contained in each thermoplastic resin layer. The lower limit of the amount of other resins is 0% by mass.

The thermoplastic resin layers (B) and (C) in the resin laminate of the present invention satisfy the following relationship.

ΔL = | L _B -L _C | ≦ 20 μm [wherein L _B and L _C represent the average film thickness of the thermoplastic resin layers (B) and (C)].

From the viewpoint of easily suppressing the warpage of the resin laminate of the present invention, ΔL is preferably 17 μm or less, and more preferably 15 μm or less. ΔL is the difference between the average film thicknesses of the thermoplastic resin layers (B) and (C), and ΔL can be adjusted within the above range by adjusting the respective film thicknesses of the thermoplastic resin layers (B) and (C). Here, the film thickness of the thermoplastic resin layer is measured using a microscope (for example, a microscope manufactured by Micro Square Co., Ltd.). The above measurement was performed at any 10 points of the thermoplastic resin layer, and the average value of the obtained values was used as the average film thickness. Since ΔL is an absolute value, its lower limit is 0 μm.

In the resin laminate of the present invention, the thermoplastic resin layers (B) and (C) further satisfy the following relationship.

△ λ _BC = ｜ △ λ _B- △ λ _C | ≦ 0.19 × 10 ^-4 [In the formula, △ λ _B and △ λ _C are expressed by the following formulas, respectively. In the following formula, λ ' _B and λ' _C represent resins. The birefringences (I), λ _B and λ _C measured in the thermoplastic resin layers (B) and (C) in the laminate are respectively expressed at 25 ° C lower than the Fica softening temperature of the thermoplastic resin layers (B) and (C). After performing the annealing treatment at a temperature for 4 hours, the birefringence (II) measured on the thermoplastic resin layers (B) and (C) in the resin laminated body].

△ λ _B = ｜ λ ' _B -λ _B ｜

△ λ _C = ｜ λ ' _C -λ _C ｜

Regarding λ ' _B and λ' _{C in} this specification, the birefringence (I) measured for the thermoplastic resin layers (B) and (C) in the resin laminate is an automatic birefringence meter (for example, manufactured by Oji Measurement Co., Ltd.) "KOBRA-CCD") measures the phase difference (R) of the thermoplastic resin layer (B) or (C) at a wavelength of 590 nm in the resin laminate, and calculates the birefringence (λ) from the obtained phase difference by the following formula.

λ = R / L [wherein λ represents birefringence, R represents a phase difference at a wavelength of 590 nm, and L represents a short side length (nm) of a sample for measuring a phase difference].

Regarding λ _B and λ _C in this specification, the thermoplastic resin layer (B) in the resin laminate is annealed at a temperature 25 ° C lower than the Ficca softening temperature of the thermoplastic resin layers (B) and (C). The birefringence (II) measured in (C) is a thermoplastic resin layer (B) measured by using an annealed resin laminate and an automatic birefringence meter (for example, "KOBRA-CCD" manufactured by Oji Measurement Co., Ltd.) or (C) The phase difference (R) at a wavelength of 590 nm, and the birefringence (λ) calculated from the obtained phase difference by the following formula. The annealing treatment is a treatment in which the resin laminate is left at a temperature 25 ° C lower than the Ficah softening temperature of the thermoplastic resin layers (B) and (C) for 4 hours. The phenanthrene of the thermoplastic resin layers (B) and (C) When the card softening temperature is different, the annealing treatment is performed at a temperature 25 ° C lower than the high Ficca softening temperature.

λ = R / L [where λ is birefringence, R is a phase difference at a wavelength of 590 nm, and L is a short side length (nm) of a sample for measuring a phase difference. ]

In one aspect of the present invention in which the thermoplastic resin layers (B) and (C) are (meth) acrylic resin layers, from the viewpoint of easily suppressing warpage of the resin laminate of the present invention, Δλ _B and Δλ _C It is preferably 0.16 × 10 ^-4 or less, and more preferably 0.15 × 10 ^-4 or less. In another aspect of the present invention in which the thermoplastic resin layers (B) and (C) are polycarbonate resin layers, from the same viewpoint, Δλ _B and Δλ _{C are} preferably 0.61 × 10 ^-4 or less, respectively. , More preferably 0.60 × 10 ^-4 or less. △ λ _B and △ λ _C refer to the difference between birefringence (I) and birefringence (II). The birefringence (I) is the birefringence of the thermoplastic resin layers (B) and (C) in the resin laminate. The birefringence (II) refers to the thermoplastic resin layers (B) and (C) measured after the resin laminate is subjected to the above-mentioned annealing treatment to remove the orientation inherent birefringence generated during molding in the thermoplastic resin layers (B) and (C). ) Of birefringence. The larger the difference is, the larger the strain of the polymer arrangement of the resin generated when the layers are formed. Δλ _B and Δλ _C are within the above range by adjusting the cooling rate during the production of the resin laminate. Since Δλ _B and Δλ _C are absolute values, their lower limit values are 0.

From the viewpoint of easily suppressing warpage of the resin laminate of the present invention, Δλ _{BC is} preferably 0.18 × 10 ^-4 or less. △ λ _BC is the absolute value of the difference between the birefringence (II) and the birefringence (I) of the thermoplastic resin layer (B) minus the difference between the birefringence (II) and the birefringence (I) of the thermoplastic resin layer (C), A larger value indicates that the degree of strain generated during the molding process is significantly different between the thermoplastic resin layer (B) and the thermoplastic resin layer (C). Δλ _BC can be adjusted to the above range by adjusting the type, amount, and cooling rate of the resin contained in the thermoplastic resin layers (B) and (C). Δλ _BC is an absolute value, so its lower limit value is 0.

The thermoplastic resin layers (B) and (C) having strains in the polymer arrangement of the resin laminate within a specific range are considered to be the resin laminates of the present invention that are less prone to warp even when used under conditions such as high temperature and humidity. One reason.

The thermoplastic resin layers (B) and (C) in the resin laminate of the present invention further satisfy the following relationship.

△ T = | T _B -T _C | ≦ 4 ° C [wherein, T _B and T _C represent the Ficca softening temperatures of the thermoplastic resin layers (B) and (C), respectively].

From the viewpoint of easily suppressing the warpage of the resin laminate of the present invention, ΔT is preferably 3 ° C or lower, more preferably 2 ° C or lower, still more preferably 1 ° C or lower, and most preferably 0 ° C. △ T refers to the difference between the Fica softening temperatures of the thermoplastic resin layers (B) and (C). A larger difference indicates a larger difference in strain relaxation rate. △ T can be adjusted to the above range by adjusting the type and composition of the resin contained in the thermoplastic resin layers (B) and (C). Here, the Feika softening temperature of the thermoplastic resin layer is measured in accordance with the B50 method specified in JIS K 7206: 1999 "Plastic-Thermoplastic-Feika Softening Temperature (VST) Test Method". The Ficca softening temperature can be measured using a thermal deformation tester (for example, "148-6 type" manufactured by Yasuda Seiki Seisakusho Co., Ltd.). The measurement can be performed using a test piece having a thickness of 3 mm for each raw material. Also, △ T is an absolute value, so its The lower limit is 0.

The thermoplastic resin layers (B) and (C) are preferably a (meth) acrylic resin layer or a polycarbonate resin layer from the viewpoint of good moldability and easy adhesion to the intermediate layer (A).

Hereinafter, one aspect of the present invention in which the thermoplastic resin layers (B) and (C) are (meth) acrylic resin layers will be described. In this aspect, the thermoplastic resin layers (B) and (C) contain one or more (meth) acrylic resins. From the viewpoint of surface hardness, the thermoplastic resin layers (B) and (C) preferably contain 50% by mass or more of (meth) acrylic resin, and more preferably 60% by mass, with respect to the entire resin contained in each thermoplastic resin layer. % Or more, and more preferably 70% by mass or more.

Examples of the (meth) acrylic resin include those described in the (meth) acrylic resin contained in the intermediate layer (A). Unless otherwise specified, the preferred (meth) acrylic resin described in the intermediate layer (A) is also preferably the (meth) acrylic resin contained in the thermoplastic resin layers (B) and (C). The (meth) acrylic resin contained in the thermoplastic resin layers (B) and (C) may be the same as or different from the (meth) acrylic resin contained in the intermediate layer (A).

From the viewpoint of good forming processability and easy improvement of mechanical strength, the weight average molecular weight (Mw) of the (meth) acrylic resin is preferably 50,000 to 300,000, and more preferably 70,000 to 250,000. The weight average molecular weight was measured by a colloidal permeation chromatography (GPC) method.

In this aspect, the thermoplastic resin layers (B) and (C) may further contain a thermoplastic resin other than one (meth) acrylic resin. The thermoplastic resin other than the (meth) acrylic resin is preferably a thermoplastic resin compatible with the (meth) acrylic resin. Specific examples include methyl methacrylate / phenethyl Ene / maleic anhydride copolymer (for example, “RESISFY” manufactured by Denki Chemical Industries), methyl methacrylate / methacrylic acid copolymer (for example, “ALTUGLAS HT121” manufactured by Arkema), and polycarbonate resin. From the viewpoint of heat resistance, thermoplastic resins other than (meth) acrylic resins have a Ficca softening temperature of 115 ° C or higher as measured in accordance with JIS K 7206: 1999, more preferably 117 ° C or higher, and even more preferably Above 120 ° C. From the viewpoints of heat resistance and surface hardness, the thermoplastic resin layers (B) and (C) are preferably free of a vinylidene fluoride resin.

In this aspect, from the viewpoint of improving the scratch resistance, the pencil hardness of the thermoplastic resin layers (B) and (C) is preferably HB or higher, more preferably F or higher, and still more preferably H or higher.

Next, another aspect of the present invention in which the thermoplastic resin layers (B) and (C) are polycarbonate resin layers will be described. In this aspect, the thermoplastic resin layers (B) and (C) contain one or more polycarbonate resins. From the standpoint of impact resistance, the thermoplastic resin layers (B) and (C) preferably contain 60% by mass or more of a polycarbonate resin, and more preferably 70% by mass, with respect to the entire resin contained in each thermoplastic resin layer. The above is more preferably 80% by mass or more.

The polycarbonate resin can be polymerized by, for example, a phosgene method in which various dihydroxy diaryl compounds are reacted with phosgene, or a transesterification method in which dihydroxy diaryl compounds are reacted with carbonates such as diphenyl carbonate. Specific examples include polycarbonate resins produced from 2,2-bis (4-hydroxyphenyl) propane (commonly referred to as bisphenol A).

Examples of the dihydroxydiaryl compound other than bisphenol A include bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4- Hydroxyphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-third butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) Propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane bis (hydroxyaryl) ) Alkanes; 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxyphenyl) cyclohexane bis (hydroxyaryl) cycloalkanes; 4,4 Dihydroxydiaryl ethers of '-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether; 4,4'-dihydroxydiphenylsulfide Dihydroxydiaryl sulfides of ethers; 4,4'-dihydroxydiphenylsulfinium, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfinium Diaryl subfluorenes; 4,4'-dihydroxydiphenylfluorene, 4,4'-dihydroxy-3,3'-dimethyldiphenylfluorene, dihydroxydiarylfluorenes.

These are used alone or in combination of two or more kinds, but other than these, piperazine, dipiperidinyl hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, and the like can be used in combination.

The dihydroxyaryl compound may be used in combination with a trivalent or higher phenol compound as shown below. Examples of trivalent or higher phenols include resorcinol, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene, and 2,4,6-dimethyl-2 , 4,6-tri- (4-hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzene, 1,1,1-tri- (4-hydroxyphenyl ) -Ethane and 2,2-bis- [4,4- (4,4'-dihydroxydiphenyl) -cyclohexyl] -propane and the like.

Examples of the polycarbonate resin other than the polycarbonate resin include polycarbonates synthesized from isosorbide and an aromatic diol. Examples of the polycarbonate include "DURABIO (registered trademark)" manufactured by Mitsubishi Chemical Corporation.

As the polycarbonate resin, commercially available products can be used, and examples thereof include "CALIBRE (registered trademark) 301-4, 301-10, 301-15, 301-22, 301-30, 301-40, manufactured by Sumika Styron Polycarbonate Co., Ltd." SD2221W, SD2201W, TR2201 ", etc.

From the viewpoint of easily improving impact resistance and molding processability, the weight average molecular weight (Mw) of the polycarbonate resin in this aspect is preferably 20,000 to 70,000, and more preferably 25,000 to 60,000. The weight average molecular weight was measured by a colloidal permeation chromatography (GPC) method.

In this aspect, the thermoplastic resin layer (B) and (C) is preferably contained in the polycarbonate resin measured at a temperature of 300 deg.] C and a load of 1.2kg, having a melt volume rate of 3 to 120cm ^3/10 minutes ( hereinafter referred to as the MVR), more preferably 3 to 80cm ^3/10 min and more preferably from 4 to 40cm ^3/10 minutes and particularly preferably 10 to 40cm ^3/10 min. If the MVR is higher than the lower limit described above, it is preferable that the fluidity is sufficiently high and the molding process is easy in melt coextrusion molding and the like, and appearance defects are unlikely to occur. If the MVR is lower than the above upper limit, mechanical properties such as the strength of the polycarbonate resin layer are likely to be improved, so it is preferable. MVR can be measured according to JIS K 7210 under a load of 1.2 kg at 300 ° C.

In this aspect, the thermoplastic resin layers (B) and (C) may further contain a thermoplastic resin other than one or more polycarbonate resins. The thermoplastic resin other than the polycarbonate resin is preferably a thermoplastic resin compatible with the polycarbonate resin, more preferably a (meth) acrylic resin, and even more preferably a methacrylic resin having an aromatic ring or a cycloolefin in the structure. . The thermoplastic resin layers (B) and (C) contain a polycarbonate resin and the above (meth) acrylic resin, and can make the surface hardness of the thermoplastic resin layers (B) and (C) higher than those containing only the polycarbonate resin Is better.

As long as the effect of the present invention is not inhibited, at least one of the intermediate layer (A), the thermoplastic resin layers (B), and (C) of the resin laminate of the present invention may further contain various additives generally used. Examples of the additives include stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, foaming agents, slip agents, release agents, antistatic agents, flame retardants, release agents, polymerization inhibitors, flame retardant additives, Colorants such as reinforcing agents, nucleating agents, and bluing agents.

Examples of the colorant include a compound having an anthraquinone skeleton and a compound having a phthalocyanine skeleton. Among these, a compound having an anthraquinone skeleton is preferred from the viewpoint of heat resistance.

When at least one of the intermediate layer (A), the thermoplastic resin layers (B), and (C) further contains a colorant, the content of the colorant in each layer can be appropriately selected depending on the purpose, the type of the colorant, and the like. When the bluing agent is used as the coloring agent, the content may be about 0.01 to 10 ppm relative to the total resin contained in each layer containing the bluing agent. The content is preferably 0.01 ppm or more, more preferably 0.05 ppm or more, still more preferably 0.1 ppm or more, more preferably 7 ppm or less, still more preferably 5 ppm or less, still more preferably 4 ppm or less, and particularly preferably 3 ppm or less. The bluing agent can be suitably used by a publicly known agent. Examples of the bluing agent include: Macrolex (registered trademark) Blue RR (manufactured by Bayer), Macrolex (registered trademark) BLUE 3R (manufactured by Bayer), Sumiplast (registered trademark) ViloetB (Sumika (Manufactured by Chemtex) and POLYSYNTHREN (registered trademark) BLUE RLS (manufactured by CLARIANT), Diaresin Violet D, Diaresin Blue G, and Diaresin Blue N (the above are made by Mitsubishi Chemical Corporation).

The ultraviolet absorber is not particularly limited, and various conventionally known ultraviolet absorbers can be used. For example, an ultraviolet absorber having an absorption maximum at 200 to 320 nm or 320 to 400 nm can be mentioned. Specific examples thereof include a triazine-based ultraviolet absorber, a diphenylketone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, a benzoate-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber. The ultraviolet absorbent may be used singly or in combination of two or more kinds. From the viewpoint of more effectively protecting against damage caused by ultraviolet rays, it is preferable to use at least one ultraviolet absorber having an absorption maximum at 200 to 320 nm and at least one ultraviolet absorbent having an absorption maximum at 320 to 400 nm. As the ultraviolet absorber, a commercially available product can be used. For example, "Kemisorb 102" (2,4-bis (2,4-dimethylphenyl) -6- (2-hydroxy-4-N- Octyloxyphenyl) -1,3,5-triazine) (absorbance 0.1), "ADEKASTAB LA-F70" (2,4,6-tris (2-hydroxy-4-hexyloxy) manufactured by ADEKA Corporation -3-methylphenyl) -1,3,5-triazine) (absorbance 0.6), `` ADEKASTAB LA-31, LA-31RG, LA-31G '' (2,2'-methylenebis (4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol) (absorbance 0.2), "ADEKASTAB LA-46" (2 -(4,6-diphenyl-1,3,5-triazin-2-yl) -5- (2- (2-ethylhexyloxy) ethoxy) phenol) (absorbance 0.05), Or "Tinuvin 1577" (2,4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -1,3,5-triazine) (absorbance 0.1) manufactured by BASF Japan Co., Ltd. The illustrated absorbance of the ultraviolet absorbent is 380 nm. The ultraviolet absorbent can be dissolved in chloroform at a concentration of 10 mg / L and measured using a spectrophotometer (for example, spectrophotometer U-4100 manufactured by HITACHI).

When at least one of the intermediate layer (A), the thermoplastic resin layers (B), and (C) further contains an ultraviolet absorber, the content of the ultraviolet absorber in each layer can be appropriately selected according to the purpose, the type of the ultraviolet absorber, and the like. For example, the content of the ultraviolet absorbent may be about 0.005 to 2.0% by mass based on the total resin contained in each layer containing the ultraviolet absorbent. The content of the ultraviolet absorber is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and still more preferably 0.03% by mass or more. The content of the ultraviolet absorber is preferably 1.5% by mass or less, and more preferably 1.0% by mass or less. From the viewpoint that the ultraviolet absorption effect is easily improved, the content of the ultraviolet absorber is preferably at least the above lower limit, and if it is below the above upper limit, it is easy to prevent the color (for example, yellowness YI) of the resin laminate from changing, so . For example, it is preferable to use the said commercial item "ADEKASTAB LA-31, LA-31RG, LA-31G" in the said quantity.

In another aspect of the present invention, the thermoplastic resin layers (B) and (C) are polycarbonate resin layers, and contain an ultraviolet absorber in an amount of 0.005 to 2.0% by mass based on the total resin contained in each thermoplastic resin layer. On the other hand, it is preferable to obtain a resin laminate having excellent light resistance.

From the viewpoint of easily suppressing the warp of the resin laminated body of the present invention, the average film thickness of the resin laminated system resin laminated body of the present invention is preferably 100 to 2000 μm, and the films of the thermoplastic resin layers (B) and (C) The thickness average is preferably 10 to 200 μm, respectively.

From the viewpoint of the rigidity of the resin laminate, the average film thickness of the resin laminate of the present invention is preferably 100 μm or more, more preferably 200 μm or more, and still more preferably 300 μm or more. From the perspective of transparency From a viewpoint, it is preferably 2000 μm or less, more preferably 1500 μm or less, and still more preferably 1000 μm or less. The film thickness of the resin laminate was measured with a digital micrometer. The average value of the above measurement at 10 points of the resin laminate was taken as the average film thickness.

From the viewpoint of easily improving the surface hardness, the average film thickness of the thermoplastic resin layers (B) and (C) in the resin laminate of the present invention is preferably 10 μm or more, more preferably 30 μm or more, and even more preferably 50 μm. the above. From the viewpoint of the dielectric constant, it is preferably 200 μm or less, more preferably 175 μm or less, and still more preferably 150 μm or less. The method for measuring the average film thickness of the thermoplastic resin layer is as described above.

From the viewpoint of the dielectric constant, the average film thickness of the intermediate layer (A) in the resin laminate of the present invention is preferably 100 μm or more, more preferably 200 μm or more, and still more preferably 300 μm or more. From the viewpoint of transparency, the thickness is preferably 1500 μm or less, more preferably 1200 μm or less, and still more preferably 1000 μm or less. The average film thickness of the intermediate layer (A) can be measured in the same manner as the average film thickness of the thermoplastic resin layer.

From the viewpoint of obtaining sufficient functions when used in a display device such as a touch panel, the resin laminate of the present invention preferably has a dielectric constant of 3.5 or more, more preferably 4.0 or more, and even more preferably 4.1 or more. The upper limit of the dielectric constant is not particularly limited, but is usually 20. The dielectric can be adjusted by adjusting the type or amount of vinylidene fluoride resin contained in the intermediate layer (A) of the resin laminate of the present invention, or by adding a high dielectric constant compound such as ethylene carbonate or propylene carbonate. The electric coefficient is adjusted to the above range. The dielectric constant is based on JIS K 6911: 1995. Let it stand for 24 hours in an environment with a humidity of 50%, and measure the value at 3V, 100kHz by the automatic balance bridge method under this environment. A commercially available apparatus can be used for the measurement, and for example, "precision LCR meter HP4284A" manufactured by Agilent Technologies, Inc. can be used.

The resin laminate of the present invention is preferably transparent when visually observed. Specifically, the resin laminate of the present invention preferably has a total light transmittance (Tt) of 85% or more as measured in accordance with JIS K 7361-1: 1997, more preferably 88% or more, and still more preferably 90% or more. . The upper limit of total light transmittance is 100%. It is preferable that the resin laminated body after being exposed to an environment of 60 ° C. and a relative humidity of 90% for 120 hours has a total light transmittance in the above range.

The resin laminated body of the present invention preferably has the following haze: The resin laminated body is used after being exposed to an environment of 60 ° C. and a relative humidity of 90% for 120 hours, and measured in accordance with JIS K 7136: 2000, which has 2.0%. The following haze is more preferably 1.8% or less, and still more preferably 1.5% or less. The resin laminate of the present invention preferably has the following yellowness (Yellow Index: YI value): The resin laminate is used in accordance with JIS Z 8722 after being exposed for 120 hours in an environment of 60 ° C and a relative humidity of 90%: As measured in 2009, it has a yellowness of 1.5 or less, more preferably 1.4 or less, and even more preferably 1.3 or less. The resin laminate of the present invention having the above-mentioned haze and yellowness is preferably less prone to warp even when used in an environment such as high temperature and high humidity, and also maintains transparency and easily suppresses yellowing. Therefore, it is preferable.

The resin laminate of the present invention may further include at least one functional layer in addition to the intermediate layer (A), the thermoplastic resin layers (B), and (C). The functional layer is preferably present in the thermoplastic resin layer (B) and / or (C) and the intermediate layer (A). The surface on the opposite side. Examples of the functional layer include a hard coating layer, an anti-reflection layer, an anti-glare layer, an anti-static layer, and an anti-fingerprint layer. These functional layers may be laminated on the resin laminate of the present invention through an adhesive, or may be a coating layer by coating. As the functional layer, for example, a hardened film described in Japanese Patent Application Laid-Open No. 2013-86273 can be used. The functional layer may be, for example, a coating method, a sputtering method, or a vacuum evaporation method on one or both sides of at least one functional layer selected from the group consisting of a hard coating layer, an anti-glare layer, an antistatic layer, and an anti-fingerprint layer. The layer further coated with the anti-reflection layer may be a layer in which an anti-reflection sheet is bonded to one or both sides of the at least one functional layer.

The thickness of the functional layer may be appropriately selected according to the purpose of each functional layer, but from the viewpoint of easily displaying functions, it is preferably 1 μm or more, more preferably 3 μm or more, and still more preferably 5 μm or more in order to prevent the functional layer from cracking From a viewpoint, it is preferably 100 μm or less, more preferably 80 μm or less, and still more preferably 70 μm or less.

The resin laminate of the present invention can be produced from a resin composition (A) provided to the intermediate layer (A), and resin compositions (B) and (C) provided to the thermoplastic resin layers (B) and (C), respectively. In this specification, the resin compositions (B) and (C) may be resins containing at least the thermoplastic resin layers (B) and (C), and may be a composition containing two or more components such as resins and optional additives. The resin may be a single type of resin.

The resin composition (A) is usually obtained by kneading a (meth) acrylic resin and a vinylidene fluoride resin. The kneading can be performed, for example, by a method including the following steps, which are melt-kneading at a temperature of 150 to 350 ° C and a shear rate of 10 to 1000 / second.

The temperature at the time of performing the melt-kneading is preferably 150 ° C or higher, so that the resin can be sufficiently melted, so it is preferable. If it is 350 ° C or lower, it is easy to suppress the thermal decomposition of the resin, which is preferable. In addition, when the shear rate during melt-kneading is 10 / second or more, it is preferable that the resin is sufficiently kneaded, and if it is 1000 / second or less, decomposition of the resin is easily suppressed, so it is preferable.

In order to obtain a resin composition in which the components are more uniformly mixed, the melt-kneading is preferably performed at a temperature of 180 to 300 ° C, more preferably 200 to 300 ° C, preferably a shear rate of 20 to 700 / second, and more It is preferably 30 to 500 / second.

As the machine used for the melt-kneading, a general mixer or kneader can be used. Specific examples include a single-shaft kneader, a double-shaft kneader, a multi-shaft extruder, a Henschel mixer, a Banbury mixer, a kneader, and a roll mill. In order to increase the shear rate within the above range, a high-shear processing device or the like can be used.

The resin compositions (B) and (C) can also be produced in the same manner as the resin composition (A), for example, by melt-kneading at the above-mentioned temperature and shear rate. In addition, for example, when the thermoplastic resin layers (B) and (C) contain one type of thermoplastic resin, the resin laminate can be produced by performing melt extrusion described below without prior melt-kneading.

When the intermediate layer (A), the thermoplastic resin layers (B), and (C) contain additives, the additives may be contained in the resin contained in each layer in advance, or may be added when the resin is melt-kneaded, or after the resin is melt-kneaded. It can also be added when a resin laminate is produced using a resin composition.

Has at least an intermediate layer (A), and each exists in the intermediate layer The thermoplastic resin layers (B) and (C) on both sides of the resin laminate of the present invention can be composed of a resin such as a melt extrusion molding method, a solution casting film forming method, a hot pressing method, and an injection molding method. (A) to (C) The layers (A) to (C) are made separately, and these are laminated through, for example, an adhesive and an adhesive, and the resin composition (A) to ( C) It is manufactured by lamination and integration by melt coextrusion. When manufacturing a resin laminate by lamination, it is preferable to use an injection molding method and a melt extrusion molding method for producing each layer, and it is more preferable to use a melt extrusion molding method. In the resin laminated body of the present invention, compared with the resin laminated body produced by lamination, the resin composition (A) to (C) is usually melt-coextruded, and the manufacturer usually obtains easy secondary molding. The resin laminate is preferred.

Melt co-extrusion molding is performed by, for example, putting the resin composition (A) and the resin compositions (B) and (C) into two or three uniaxial or biaxial extruders, respectively, and melt-kneading them separately. It is a molding method in which an intermediate layer (A) formed of a resin composition (A) and thermoplastic resin layers (B) and (C) are laminated and integrated into a die or a multi-manifold die. When the resin composition (B) and (C) are the same composition, the melt-kneaded one composition can be divided into two equally through a feeding die in one extruder to form a thermoplastic resin layer (B). And (C). The obtained resin laminated body is preferably cooled and solidified by, for example, a roll device.

The resin laminated body of the present invention obtained by cutting the laminated body manufactured in the above-mentioned manner is circulated in the form of a resin laminated body having a width of 500 to 3000 mm and a length of 500 to 3000 mm, for example.

The resin laminate of the present invention can be used in various display devices. A display device refers to a device having a display element and contains a light-emitting element Or a light emitting device as a light source. Examples of the display device include a liquid crystal display device, an organic electroluminescence (EL) display device, an inorganic electroluminescence (EL) display device, a touch panel display device, an electron emission display device (e.g., a field emission display device (FED), a surface Field emission display device (SED)), electronic paper (display device using electronic printing ink, electrophoretic element), plasma display device, projection display device (e.g. display device with grid light valve (GLV), digital micromirror device (DMD) display devices), and piezoelectric ceramic displays. The liquid crystal display device includes any one of a transmissive liquid crystal display device, a transflective liquid crystal display device, a reflective liquid crystal display device, a direct-view liquid crystal display device, and a projection liquid crystal display device. These display devices may be a display device that displays a two-dimensional image, or a stereoscopic display device that displays a three-dimensional image. The resin laminate of the present invention is suitably used as a front panel or a transparent electrode in such display devices, for example.

When the resin laminate of the present invention is used as a transparent electrode in a touch panel or the like, a transparent conductive film can be formed on at least one surface of the resin laminate of the present invention to produce a transparent conductive sheet, and the transparent electrode is produced from the transparent conductive sheet.

The method for forming a transparent conductive film on at least one surface of the resin laminated body of the present invention may be directly forming a transparent conductive film on the surface of the resin laminated body of the present invention, or a plastic film previously formed with a transparent conductive film may be laminated on the resin of the present invention. Laminate surface.

The film base material of the plastic film in which the transparent conductive film is formed in advance is not particularly limited as long as it is a base material that can form a transparent conductive film, and examples thereof include polyethylene terephthalate and polyethylene naphthalate. ester, Polycarbonate, acrylic resin, polyamide, mixtures or laminates of these. In addition, before forming a transparent conductive film, the film can be coated for the purposes of improving surface hardness, preventing Newton's rings, and imparting antistatic properties.

A method of forming a film of a transparent conductive film on the resin laminated body surface area layer of the present invention in advance may be any method as long as it is a method capable of obtaining a uniform transparent sheet without generating bubbles or the like. It can be laminated by using an adhesive that is hardened by normal temperature, heating, ultraviolet or visible light, or can be attached by a transparent adhesive tape.

As a method for forming a transparent conductive film, a vacuum evaporation method, a sputtering method, a CVD method, an ion plating method, and a spray method are known, and these methods can be suitably used according to the required film thickness.

In the case of the sputtering method, for example, a general sputtering method using an oxide target, a reactive sputtering method using a metal target, and the like can be used. In this case, oxygen, nitrogen, or the like may be introduced as a reactive gas, or a method such as adding ozone, plasma irradiation, or ion assist may be used in combination. In addition, a DC, AC, or high frequency bias may be applied to the substrate as needed. Examples of the transparent conductive metal oxide used in the transparent conductive film include indium oxide, tin oxide, zinc oxide, indium-tin composite oxide, tin-antimony composite oxide, zinc-aluminum composite oxide, and indium-zinc composite oxide. Things. From the viewpoints of environmental stability and circuit processability, among these, indium-tin composite oxide (ITO) is preferred.

In addition, as a method for forming a transparent conductive film, a coating agent containing various conductive polymers capable of forming a transparent conductive film can be applied to the surface of the resin laminate of the present invention and irradiated with ionizing radiation such as heat or ultraviolet rays to thereby make Coating hardening method, etc. Conductive polymer As thiophene, polyaniline, polypyrrole, etc., these conductive polymers can be used.

The thickness of the transparent conductive film is not particularly limited. When a transparent conductive metal oxide is used, it is usually 50 to 2000Å, preferably 70 to 000Å. Within this range, both the conductivity and transparency are excellent.

The thickness of the transparent conductive sheet is not particularly limited, and the optimal thickness can be selected according to the specifications of the display product.

A touch sensor panel can be manufactured by using the resin laminated body of the present invention as a display panel and using the transparent conductive sheet produced by the resin laminated body of the present invention as a transparent electrode such as a touch screen. Specifically, the resin laminate of the present invention can be used as a window side sheet for a touch screen, and a transparent conductive sheet can be used as an electrode substrate for a touch screen of a resistance film method or a capacitance method. The touch screen is arranged in front of a liquid crystal display device or an organic EL display device, thereby obtaining an external touch sensor panel with a touch screen function.

The present invention also provides a display device including the resin laminated body of the present invention. The display device of the present invention may be, for example, the display device described above.

The present invention also provides a polarizing plate with a resin laminated body laminated with the resin laminated body of the present invention and a polarizing plate, and a display device including the polarized plate with the resin laminated body. In the polarizing plate with a resin laminated body of the present invention, the resin laminated system of the present invention is laminated on the polarizing plate through, for example, an optical adhesive such as an adhesive and an adhesive. Adhesives or adhesives can be suitably known.

Figure 2 is a schematic sectional view showing a tree containing the present invention A preferred form of the lipid-laminated liquid crystal display device. The resin laminated body 10 of the present invention is laminated on the polarizing plate 11 through the optical adhesive layer 12, and the laminated body can be disposed on the visual confirmation side of the liquid crystal cell 13. The polarizing plate 11 is usually arranged on the back side of the liquid crystal cell 13. The liquid crystal display device 14 is composed of such members. The second figure is an example of a liquid crystal display device, and the display device of the present invention is not limited to this configuration.

(Example)

Examples and comparative examples are given below to describe the present invention in detail, but the present invention is not limited to these examples.

[Fica softening temperature]

Measured in accordance with B50 method specified in JIS K 7206: 1999 "Plastic-thermoplastic-fica softening temperature (VST) test method". The Ficca softening temperature was measured with a thermal deformation tester ["148-6 continuous type" manufactured by Yasuda Seiki Seisakusho Co., Ltd.]. At this time, the test piece was formed by measuring each raw material to a thickness of 3 mm.

[Content of Alkali Metal]

It was measured by inductively coupled plasma mass spectrometry.

〔MFR〕

Measured in accordance with the method specified in JIS K 7210: 1999 "Test method for the melt mass flow rate (MFR) and melt volume flow rate (MVR) of plastic-thermoplastics". In the JIS, a poly (methyl methacrylate) -based material is measured under conditions of a temperature of 230 ° C and a load of 3.80 kg (37.3 N).

〔MVR〕

Manufactured by Toyo Seiki Seisakusho Co., Ltd. in accordance with JIS K 7210 "SEMI AUTO MELT INDEXER 2A" measured a polycarbonate resin material under the conditions of a load of 1.2 kg and 300 ° C.

[Total Transmittance and Haze]

According to JIS K 7361-1: 1997 "Test method for total transmittance of plastics-transparent materials-Part 1: Single-beam method" Haze transmittance meter ("HR- 100 ").

〔YI value〕

Measured with "Spectrophotometer SQ2000" manufactured by Nippon Denshoku Industries Co., Ltd.

[Average film thickness]

The film thickness of the resin laminate was measured with a digital micrometer. The average value of the above measurements at 10 points was taken as the average film thickness of the resin laminate.

The thickness measurement of each layer of the intermediate layer (A), the thermoplastic resin layers (B), and (C) is performed by cutting the resin laminate perpendicularly to the surface direction, grinding the cross section with sandpaper, and observing with a Micro Square microscope. Determination. The average value of the above measurements at 10 points was taken as the average film thickness of each layer.

[Birefringence (Birefringence I) of the thermoplastic resin layers (B) and (C) in the resin laminate]]

The resin laminated body was cut in a direction perpendicular to the laminated surface to obtain a rectangular parallelepiped having a size of 600 μm short sides and 8 mm long sides and a film thickness of the resin laminated body on the surface of the thermoplastic resin layer. This was fixed on glass with a cross-section facing upward to obtain a sample for phase difference measurement. The fixing system is performed using an epoxy-based adhesive. The obtained sample was set on an automatic birefringence meter so that the desired measurement layer faces the measurement light incident side (Oji Measurement Co., Ltd. "KOBRA-CCD" manufactured by the company) measures the phase difference (R) at a wavelength of 590 nm at a temperature of 23 ± 2 ° C and a humidity of 50 ± 5%. Using the obtained phase difference, the birefringence (λ) was calculated by the following formula. The birefringence thus calculated is referred to as birefringence (I).

λ = R / L [where λ is birefringence, R is a phase difference, and L is the short side length (nm) of the sample for phase difference measurement. ]

[The birefringence (birefringence) of the thermoplastic resin layers (B) and (C) in the resin laminate after annealing for 4 hours at a temperature 25 ° C lower than the Fica softening temperature of the thermoplastic resin layers (B) and (C) II)]

In order to remove strain during molding, the resin laminate is placed in an oven set at a temperature lower than the Ficah softening temperature of the thermoplastic resin layers (B) and (C) by 25 ° C for 4 hours, and then annealed to obtain the removal molding time. Resin laminate for strained birefringence (II) measurement. Using the obtained resin laminate, the phase difference was measured by the same method as the above-mentioned measurement of birefringence (I), and the birefringence was calculated by substituting it into the above formula. The birefringence thus calculated is referred to as birefringence (II). In addition, when the Feika softening temperatures of the thermoplastic resin layers (B) and (C) are different, the annealing treatment is performed at a temperature which is 25 ° C lower than the high Feika softening temperature.

[Evaluation of warpage]

The produced sheet-like resin laminate was cut to a size of 100 × 56 mm, and a sample for warpage evaluation was prepared. This sample was left to stand in a constant temperature and humidity machine at a temperature of 60 ° C. and a relative humidity of 90% for 120 hours, and the change in warpage before and after the evaluation was evaluated. The evaluation was performed by observing the 4 ends of the sample with a high-precision CCD micrometer manufactured by Keyence, measuring the height of the warpage generated, and calculating the average of the warping heights of the 4 ends.

[Manufacturing example 1]

97.7 parts by mass of methyl methacrylate and 2.3 parts by mass of methyl acrylate were mixed, and 0.05 parts by mass of a chain transfer agent (octyl mercaptan) and 0.1 parts by mass of a release agent (stearyl alcohol) were added to obtain a monomer mixed solution. In addition, 100 parts by mass of methyl methacrylate was added with 0.036 parts by mass of a polymerization initiator [1,1-di (third butyl peroxide) 3,3,5-trimethylcyclohexane] to obtain Starter mixture. The monomer mixed liquid and the starter mixed liquid were continuously supplied to the completely mixed type polymerization reactor in a flow ratio of 8.8: 1, and were polymerized with an average residence time of 20 minutes and a temperature of 175 ° C to an average polymerization rate of 54%. Partial polymer. The obtained part of the polymer was heated to 200 ° C, and introduced into a devolatizing extruder with pores. At 240 ° C, the unreacted monomer was devolatized from the pores, and the polymer after the devolatization was squeezed out in a molten state It was cut out after water cooling, and pelletized methacrylic resin (i) was obtained.

The obtained pellet-like methacrylic resin composition was analyzed by thermal decomposition gas chromatography under the conditions shown below, and respective peak areas corresponding to methyl methacrylate and acrylate were measured. As a result, the structural unit derived from methyl methacrylate in the methacrylic resin (i) was 97.0% by mass, and the structural unit derived from methyl acrylate was 3.0% by mass.

[Construction unit content by thermal decomposition gas chromatography]

(Thermal decomposition conditions)

Sample preparation: Fine-scale methacrylic resin composition (about 2 to 3 mg), put it in the central part of the tube-shaped metal groove, overlap the metal groove, and tightly seal both ends with pliers.

Thermal decomposition device: CURIE POINT PYROLYZER JHP-22 (manufactured by Japan Analytical Industry Co., Ltd.).

Metal tank: Pyrofoil F590 (manufactured by Japan Analytical Industry Co., Ltd.).

Set temperature of constant temperature bath: 200 ℃.

Set temperature of insulation tube: 250 ℃.

Thermal decomposition temperature: 590 ° C.

Thermal decomposition time: 5 seconds.

(Gas chromatography analysis conditions)

Gas chromatography analysis device: GC-14B (manufactured by Shimadzu Corporation).

Detection method: FID.

String: 7G 3.2m × 3.1mm (Made by Shimadzu Corporation).

Filler: FAL-M (manufactured by Shimadzu Corporation).

Carrier gas: Air / N2 / H2 = 50/100/50 (kPa), 80ml / min.

Heating conditions of the column: After maintaining at 100 ° C for 15 minutes, the temperature was increased to 150 ° C at 10 ° C / minute, and the temperature was maintained at 150 ° C for 14 minutes.

INJ temperature: 200 ° C.

DET temperature: 200 ° C.

When the methacrylic resin composition is thermally decomposed under the above thermal decomposition conditions, and the generated decomposition products are measured under the above-mentioned gas chromatography analysis conditions, the detected peak areas (a1) of the corresponding methyl methacrylate and Corresponds to the peak area (b1) of acrylate. Then, the peak area ratio A (= b1 / a1) is obtained from the peak areas. On the other hand, a standard product of a methacrylic resin having a weight ratio of acrylate units to W ₀ (known) relative to methyl methacrylate units is thermally decomposed under the above thermal decomposition conditions, and the resulting decomposition product is When measuring by the above-mentioned gas chromatography analysis conditions, the peak area (a ₀ ) of the corresponding methyl methacrylate and the peak area (b ₀ ) of the corresponding acrylate are measured, and the peak area ratio is obtained from the peak areas. A0 (= b ₀ / a ₀ ). Then, a factor f (= W ₀ / A ₀ ) is obtained from the peak area ratio A ₀ and the weight ratio W ₀ .

Multiplying the aforementioned peak area ratio A by the aforementioned factor f, thereby obtaining the weight ratio W of the acrylate unit to the methyl methacrylate unit in the copolymer contained in the methacrylic resin composition, and the weight ratio W The ratio (mass%) of a methyl methacrylate unit with respect to the total of a methyl methacrylate unit and an acrylate unit, and the ratio (mass%) of an acrylate unit with respect to the said total are calculated.

[Manufacture example 2]

A pelletized methacrylic resin (ii) was obtained in the same manner as in Production Example 1 except that the methyl methacrylate was changed to 98.9 parts by mass, the methyl acrylate was changed to 1.1 parts by mass, and the chain transfer agent was changed to 0.16 parts by mass. , Determine the content of the structural unit. The structural unit derived from methyl methacrylate in the methacrylic resin (ii) was 97.5% by mass, and the structural unit derived from methyl acrylate was 2.5% by mass.

[Manufacture example 3]

According to Example 3 of Japanese Patent Publication No. 55-27576, an acrylic rubber pellet having a spherical three-layer structure and an average particle diameter of 0.22 μm was produced. And used as acrylic rubber particles (i). The acrylic rubber particles (i) include an innermost layer of a hard polymer obtained by polymerization of methyl methacrylate and a small amount of allyl methacrylate, butyl acrylate as a main component, and further styrene and a small amount of formic acid. An intermediate layer of an elastic polymer obtained by polymerizing allyl acrylate, and an outermost layer of a hard polymer obtained by polymerizing methyl methacrylate and a small amount of methyl acrylate. The acrylic rubber particles were mixed with a methacrylic resin and formed into a film. The elastic polymer (intermediate layer) was dyed with ruthenium oxide in the cross section of the film, and the diameter of the dyed portion was observed with an electron microscope to determine the acrylic rubber. The average particle diameter of the particles (i).

65 parts of the pellets of the methacrylic resin (i) and 35 parts of the acrylic rubber particles (i) were mixed with a super mixer, and melt-kneaded with a biaxial extruder to form pellets.

The physical properties of the methacrylic resins (i) to (iii) obtained in Production Examples 1 to 3 are shown in Table 1.

[Manufacture example 4]

In order to make the bluing agent masterbatch (MB), 99.99 parts by weight of the methacrylic resin (i) obtained in Production Example 1 and 0.01 parts by weight of the coloring agent were dry-mixed to a thickness of 40 mm. A uniaxial extruder (manufactured by Tanabe Plastic Machinery Co., Ltd.) was melt-mixed at a set temperature of 250 to 260 ° C to obtain colored masterbatch pellets (MB (i)). The coloring agent was a bluing agent ("Sumiplast (registered trademark) VioletB" manufactured by Sumika Chemtex Co., Ltd.).

In Examples and Comparative Examples, commercially available vinylidene fluoride resins having physical properties shown in Table 2 were used.

Vinylidene fluoride resin (i): polyvinylidene fluoride produced by suspension polymerization.

Vinylidene fluoride resin (ii): polyvinylidene fluoride made by emulsion polymerization.

The weight average molecular weight (Mw) of vinylidene fluoride resin is measured by colloidal permeation chromatography (GPC). Using polystyrene as a standard reagent, a calibration curve was prepared from the dissolution time and molecular weight, and the weight average molecular weight of each resin was measured. Specifically, 40 mg of resin was dissolved in 20 ml of N-methylpyrrolidone (NMP) solvent to prepare a measurement sample. The measuring device is equipped with two tubes of "TSKgel SuperHM-H" and one tube of "SuperH2500" made by TOSOH Co., Ltd. in series, and the detector is an RI detector.

In the examples and comparative examples, commercially available products shown below were used as the polycarbonate resin. The physical properties of the resin are shown in Table 3.

Polycarbonate resin (i): Sumika Styron Polycarbonate Division "CALIBRE (registered trademark) 301-30".

The weight average molecular weight of the polycarbonate resin was measured by GPC. Using a methacrylic resin manufactured by Showa Denko Corporation with a narrow molecular weight distribution and known molecular weight as a standard reagent, a calibration curve was prepared from the dissolution time and molecular weight, and the weight average molecular weight was measured. Specifically, 40 mg of a resin was dissolved in 20 ml of a tetrahydrofuran (THF) solvent to prepare a measurement sample. The measuring device is a series of two "TSKgel SuperHM-H" columns manufactured by TOSOH Co., Ltd. and one "SuperH2500" in series, and the detector is an RI detector.

[Production of resin laminated bodies of Examples 1 to 3 and Comparative Examples 1 to 6]

The methacrylic resin and vinylidene fluoride resin shown in Tables 1 and 2 and the masterbatch pellet MB (i) obtained in Production Example 4 were mixed in the ratio shown in Table 4 to obtain an intermediate layer (A). Resin composition (A). The resin compositions (B) and (C) for forming the thermoplastic resin layers (B) and (C) are those using the methacrylic resin shown in Table 1, the mixture obtained in Production Example 3, or the polycarbonate resin shown in Table 3. . A resin laminate was produced from these resin compositions using the apparatus shown in FIG. 1. Specifically, the resin composition (A) is 65 mm Uniaxial extruder 2 [manufactured by Toshiba Machinery Co., Ltd.], the resin composition (B) and (C) are 45 mm The uniaxial extruders 1 and 3 (made by Hitachi Shipbuilding Co., Ltd.) were melted separately. These are then supplied to three types of three-layer distribution-type supply ports 4 with a set temperature of 230 to 270 ° C, and are distributed in a three-layer configuration. Two types of three-layer distribution] were extruded and laminated so as to have the structure shown in layer B / A layer / C layer to obtain a film-like molten resin 6. The obtained film-like molten resin 6 was sandwiched between the first cooling roll 7 (diameter 350 mm) and the second cooling roll 8 (diameter 450 mm) arranged opposite to each other, and then sandwiched between the second roll 8 while being wound around the second roll 8 After being wound between 8 and the third roll 9 (diameter 350 mm), it is wound around the third cooling roll 9 and formed and cooled to obtain a resin laminate 10 having three layers each having an average film thickness as shown in Table 4. The obtained resin laminates 10 all had a total film thickness of about 800 μm, and were visually observed as colorless and transparent.

Table 5 shows the temperature of each cooling roller, the drawing speed, and the resin discharge temperature measured by a non-contact thermometer when the resin discharged from the mold was used when the resin laminate was produced.

For the thermoplastic resin layers (B) and (C) of the resin laminates of Examples 1 to 3 and Comparative Examples 1 to 5, the measurement results of ΔL, Δλ _B , Δλ _C , Δλ _BC, and △ T are shown in FIG. Following Table 6.

In the resin laminates of Examples 1 to 3 and Comparative Examples 1 to 5, the content of alkali metals (Na and K) in the intermediate layer (A) was 0.3 ppm in Examples 1, 2 and Comparative Examples 1 to 5, and in the examples 3 is 100 ppm.

The dielectric constants of the resin laminates of Examples 1 to 3 and Comparative Examples 1 to 5 were 5.2 in Example 1 and Comparative Examples 2, 3, and 5, 5.3 in Example 2, and 5.1 in Comparative Examples 1 and 4, In Example 3, it was 4.9. It can be confirmed that any of the resin laminates has a sufficient dielectric constant that can be used for a display device such as a touch panel.

Evaluations of total light transmittance (Tt), haze (Haze), and warpage were performed using the resin laminates of Examples 1 to 3 and Comparative Examples 1 to 5. Income knot The results are shown in Table 7. The resin laminates of Examples 1 to 3 and Comparative Examples 1 to 5 were exposed to an environment of 60 ° C. and a relative humidity of 90% for 120 hours, and the resin laminates after the endurance test were similarly evaluated for warpage. The results after the endurance test are also shown in Table 7.

It can be seen that the resin laminate system of the present invention shown in Examples 1 to 3 has high transparency and is less prone to warping. In addition, the resin laminates of the present invention shown in Examples 1 to 3 are less prone to warp even after a durability test under high temperature and high humidity conditions.

10‧‧‧Resin laminate

10A‧‧‧Intermediate Level (A)

10B‧‧‧Thermoplastic resin layer (B)

10C‧‧‧Thermoplastic resin layer (C)

11‧‧‧ polarizing plate

12‧‧‧ Optical Adhesive Layer

13‧‧‧LCD cell

14‧‧‧ Liquid crystal display device

Claims (15)

A resin laminate comprising at least an intermediate layer (A) and thermoplastic resin layers (B) and (C) respectively present on both sides of the intermediate layer (A); with respect to the entire resin contained in the intermediate layer (A) The intermediate layer (A) contains 10 to 90% by mass of (meth) acrylic resin and 90 to 10% by mass of vinylidene fluoride resin. The weight average molecular weight (Mw) of the (meth) acrylic resin is 100,000 to 300,000; The thermoplastic resin layers (B) and (C) satisfy the following relationship: △ L = ｜ L _B -L _C | ≦ 20μm; △ λ _BC = ｜ △ λ _B- △ λ _C | ≦ 0.19 × 10 ^-4 △ T = ｜ T _B -T _C ｜ ≦ 4 ℃; where L _B and L _C represent the average film thickness of the thermoplastic resin layers (B) and (C), respectively, and △ λ _B and △ λ _C are below Expression: △ λ _B = ｜ λ ' _B -λ _B ｜ △ λ _C = ｜ λ' _C -λ _C ｜; In the above formula, λ ' _B and λ' _C respectively represent the thermoplastic resin layer in the resin laminate The birefringences (I), λ _B and λ _C measured in (B) and (C) represent annealing at a temperature of 25 ° C lower than the Ficca softening temperature of the thermoplastic resin layers (B) and (C) for 4 hours. Then, the double measured for the thermoplastic resin layers (B) and (C) in the resin laminate Exit (II), T _B and T _C represent Pacifica thermoplastic resin layer (B) and (C) the softening temperature. The resin laminate according to item 1 of the scope of patent application, wherein the intermediate layer (A) contains 35 to 45% by mass of (meth) acrylic resin and 65% with respect to the entire resin contained in the intermediate layer (A). 25% to 55% by mass Fluoroethylene resin. The resin laminate according to item 1 or 2 of the scope of patent application, wherein the content of the alkali metal in the intermediate layer (A) is 50 ppm or less with respect to the entire resin contained in the intermediate layer (A). The resin laminate according to any one of claims 1 to 3, wherein the (meth) acrylic resin is the following (a1) and / or (a2); (a1) the average of methyl methacrylate Polymer; (a2) with respect to the total structural unit constituting the polymer, containing 50 to 99.9% by mass of a structural unit derived from methyl methacrylate, and 0.1 to 50% by mass of a structural unit derived from formula (1) A copolymer of at least one structural unit of (meth) acrylate; In the formula, R ₁ represents a hydrogen atom or a methyl group, R ₁ is R ₂ represents an alkyl group having 1 to 8 carbon atoms of hydrogen atom, R ₁ R ₂ represents an alkyl group having a carbon number of 2-8 is a methyl group. The resin laminate according to any one of claims 1 to 4, wherein the vinylidene fluoride resin is polyvinylidene fluoride. The resin laminate according to any one of claims 1 to 5, wherein the melt mass flow rate of the vinylidene fluoride resin is 0.1 to 40 g when measured under a load of 3.8 kg and a temperature of 230 ° C. /10 minutes. Resin laminate as described in any one of claims 1 to 6 The average film thickness of the resin laminate is 100 to 2000 μm, and the average film thickness of the thermoplastic resin layers (B) and (C) are 10 to 200 μm, respectively. The resin laminate according to any one of claims 1 to 7 of the scope of application for a patent, wherein the Feika softening temperatures of the thermoplastic resins contained in the thermoplastic resin layers (B) and (C) are 100 to 160 ° C, respectively. The resin laminate according to any one of claims 1 to 8, in which the thermoplastic resin layers (B) and (C) are (meth) acrylic resin layers or polycarbonate resin layers. The resin laminate according to any one of claims 1 to 9, in which the thermoplastic resin layers (B) and (C) are polycarbonate resin layers and are relative to all resins contained in each thermoplastic resin layer. It contains 0.005 to 2.0% by mass of UV absorber. The resin laminate according to any one of claims 1 to 9, in which the thermoplastic resin layers (B) and (C) contain 50% by mass or more of the total resin contained in each thermoplastic resin layer (Meth) acrylic resin. The resin laminate according to item 11 of the scope of patent application, wherein the weight average molecular weight of the (meth) acrylic resin contained in the thermoplastic resin layers (B) and (C) is 50,000 to 300,000. A display device includes the resin laminate according to any one of claims 1 to 12 of the scope of patent application. A polarizing plate with a resin laminated body is formed by laminating the resin laminated body and the polarizing plate as described in any one of items 1 to 12 of the scope of patent application. Become. A display device includes a polarizing plate with a resin laminate as described in item 14 of the scope of patent application.