CN108973281B

CN108973281B - Resin laminate

Info

Publication number: CN108973281B
Application number: CN201810503273.6A
Authority: CN
Inventors: 大松一喜; 山下恭弘; 花冈秀典
Original assignee: Sumitomo Chemical Co Ltd
Current assignee: Sumitomo Chemical Co Ltd
Priority date: 2017-05-26
Filing date: 2018-05-23
Publication date: 2020-01-03
Anticipated expiration: 2038-05-23
Also published as: JP2018199329A; CN108973281A; KR102008464B1; KR20180129675A; JP6420924B1

Abstract

The purpose of the present invention is to provide a resin laminate which can effectively suppress the occurrence of appearance defects such as cracking, wrinkling, and cloudiness during bending. A resin laminate comprising a resin layer having a dielectric constant of 3.5 or more and a hard coat layer laminated on at least one surface of the resin layer, wherein the pencil hardness on the hard coat layer side is 4B or more and satisfies the following relationships (1) to (3): l is more than or equal to 20_PET≤130 (1)，0.4≤L_HC/L_PMMA≤1.5 (2)，1≤T_HC≤30 (3)。

Description

Resin laminate

Technical Field

The present invention relates to a resin laminate applicable to a front panel of an image display device or the like.

Background

In recent years, smart phones, portable game machines, audio players, tablet terminals, and the like, which have characteristics in terms of design, have been actively developed, and studies have been made to provide a curved surface shape to an originally flat display device. As the front panel of such a display device, a glass sheet is generally used, but a resin sheet as a substitute for the glass sheet has been studied because of problems such as poor yield (for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2014-688

Disclosure of Invention

Problems to be solved by the invention

However, the inventors of the present application have found that when a resin laminate is bent, appearance defects such as cracks, wrinkles, and white turbidity may occur, and particularly when the resin laminate is bent into a shape having a large curvature, the appearance defects become conspicuous, and therefore, the resin laminate cannot be used as a front panel of a display device.

Accordingly, an object of the present invention is to provide a resin laminate capable of effectively suppressing the occurrence of appearance defects such as cracking, wrinkling, and white turbidity at the time of bending.

Means for solving the problems

The present inventors have repeatedly conducted detailed studies to solve the above problems and have completed the present invention, wherein a resin laminate capable of suppressing the occurrence of appearance defects is obtained.

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

[1] A resin laminate comprising a resin layer having a dielectric constant of 3.5 or more and a hard coat layer laminated on at least one surface of the resin layer,

the pencil hardness on the hard coating layer side is 4B or more, and satisfies the following relations of (1) to (3):

20≤L_PET≤130 (1)，

0.4≤L_HC/L_PMMA≤1.5 (2)，

1≤T_HC≤30 (3)，

[ in the formula, L_PETThe ultimate elongation (%) L, at 140 ℃ and 50mm/min, of a laminate comprising a substrate of 75 μm polyethylene terephthalate and the hard coat layer on one side of the substrate_HCThe maximum elongation (%) L at 100 ℃ and 50mm/min, when a laminate comprising a substrate of polymethyl methacrylate having a thickness of 500 μm and the hard coat layer on one surface of the substrate was stretched_PMMAThe maximum elongation (%) at 100 ℃ and at a rate of 50mm/min, T, when a substrate of polymethyl methacrylate having a thickness of 500 μm was stretched_HCFilm thickness (. mu.m) of the hard coat layer]。

[2] The resin laminate according to [1], which comprises a curved surface portion having a radius of curvature R of 0.1 mm. ltoreq.R.ltoreq.14 mm.

[3] The resin laminate according to [1] or [2], wherein the resin layer has a main layer (a) containing a (meth) acrylic resin and a thermoplastic resin layer (B) laminated on at least one surface of the main layer (a), and satisfies a relationship of the following formula (4):

0.2≤Y/X≤15 (4)

[ wherein X represents the ultimate elongation (%) when the main layer (A) having a thickness of 500 μm is stretched at 23 ℃ at a rate of 50mm/min, and Y represents the ultimate elongation (%) when the thermoplastic resin layer (B) having a thickness of 500 μm is stretched at 23 ℃ at a rate of 50mm/min ].

[4] The resin laminate according to any one of [1] to [3], wherein the resin layer has a main layer (A) containing a (meth) acrylic resin and a thermoplastic resin layer (B) laminated on at least one surface of the main layer (A), and the main layer (A) contains a (meth) acrylic resin and a vinylidene fluoride resin.

ADVANTAGEOUS EFFECTS OF INVENTION

The resin laminate of the present invention can effectively suppress the occurrence of appearance defects such as cracking, wrinkling, and cloudiness during bending.

Drawings

FIG. 1 is a schematic cross-sectional view showing an example of a resin laminate of the present invention.

Fig. 2 is a schematic cross-sectional view showing an example of a resin laminate obtained by bending the resin laminate of the present invention.

FIG. 3 is a view showing an inscribed circle formed by a curved surface portion in a cross section of a curved resin laminate of the present invention.

Fig. 4 is a schematic view showing an example of an apparatus for producing a resin layer of the resin laminate of the present invention.

Description of the reference numerals

1 … resin laminate

2 … resin layer

3 … Main layer

4. 5 … thermoplastic resin layer

6.7 … hard coating

8 … flat part

9 … curved surface part

Detailed Description

The resin laminate of the present invention includes a resin layer having a dielectric constant of 3.5 or more and a hard coat layer laminated on at least one surface of the resin layer.

[ resin layer ]

The resin layer has a high dielectric constant (preferably a dielectric constant of 3.5 or more, more preferably 3.6 or more, and further preferably 3.7 or more) from the viewpoint of obtaining a function sufficient for use in a display device such as a touch panel. The upper limit of the dielectric constant is not particularly limited, and is usually 20. The dielectric constant is a value measured by: the resin laminate of the present invention was left to stand at 23 ℃ for 24 hours in an environment of 50% relative humidity in accordance with JIS K6911: 1995, and measured at 3V and 100kHz by the self-equilibrium bridge method in this environment. For the measurement, a commercially available apparatus such as "precision LCR meter HP 4284A" manufactured by Agilent Technologies may be used.

The resin contained in the resin layer is not particularly limited as long as it is a resin capable of forming a resin layer having a dielectric constant of 3.5 or more, and examples thereof include (meth) acrylic resins, vinylidene fluoride resins, polycarbonate resins, polyamide resins, polystyrene resins, acrylonitrile-styrene copolymers, methyl methacrylate-styrene copolymers, polyethylene terephthalate, polyether sulfone, cycloolefin resins, and the like. Among these, a (meth) acrylic resin and a vinylidene fluoride resin are preferable. These resins may be used alone or in combination of two or more. When two or more resins are used, the amounts of the resin having a high dielectric constant and the resin having a low dielectric constant can be appropriately adjusted so that the dielectric constant is adjusted to 3.5 or more.

Examples of the (meth) acrylic resin [ sometimes referred to as a (meth) acrylic resin (M) ] contained in the resin layer include homopolymers of (meth) acrylic monomers such as (meth) acrylate and (meth) acrylonitrile, copolymers of 2 or more (meth) acrylic monomers, and copolymers of (meth) acrylic monomers and monomers other than (meth) acrylic monomers. In the present specification, the term "(meth) acryl-" means "acryl-" or "methacryl-".

The (meth) acrylic resin is preferably a methacrylic resin from the viewpoint of easily improving the molding processability, hardness, weather resistance, transparency, and the like of the resin laminate. The methacrylic resin is a polymer of a monomer mainly composed of a methacrylic acid ester (alkyl methacrylate), and examples thereof include a homopolymer of a methacrylic acid ester (polyalkylmethacrylate), a copolymer of 2 or more methacrylic acid esters, a copolymer of 50 mass% or more of a methacrylic acid ester and 50 mass% or less of a monomer other than a methacrylic acid ester, and the like. The copolymer of a methacrylate ester and a monomer other than a methacrylate ester is preferably a copolymer of a methacrylate ester in an amount of 70 mass% or more and another monomer in an amount of 30 mass% or less, more preferably a copolymer of a methacrylate ester in an amount of 90 mass% or more and another monomer in an amount of 10 mass% or less, with respect to the total amount of monomers, from the viewpoint of easily improving optical properties and weatherability.

Examples of the monomer other than the methacrylate ester include acrylate esters and monofunctional monomers having 1 polymerizable carbon-carbon double bond in the molecule.

Examples of the monofunctional monomer include styrene monomers such as styrene, α -methylstyrene and vinyltoluene; alkenyl cyanides such as acrylonitrile and methacrylonitrile; acrylic acid; methacrylic acid; maleic anhydride; n-substituted maleimides, and the like.

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

From the viewpoint of easily improving the molding processability, hardness, weather resistance, transparency, and the like of the resin laminate, (meth) acrylic resins are particularly preferably:

(a1) homopolymers of methyl methacrylate; or

(a2) A copolymer comprising 50 to 99.9 mass% (preferably 70.0 to 99.8 mass%, more preferably 80.0 to 99.7 mass%) of a structural unit derived from methyl methacrylate and 0.1 to 50 mass% (preferably 0.2 to 30 mass%, more preferably 0.3 to 20 mass%) of at least 1 structural unit derived from a (meth) acrylate represented by formula (1) based on the total structural units constituting the copolymer,

[ chemical formula 1]

[ in the formula, R₁Represents a hydrogen atom or a methyl group, R₁When it is a hydrogen atom, R₂Represents an alkyl group having 1 to 8 carbon atoms, R₁When it is methyl, R₂Represents an alkyl group having 2 to 8 carbon atoms.](ii) a Or a mixture of (a1) and (a 2).

Here, the content of each structural unit can be calculated by analyzing the obtained polymer by pyrolysis gas chromatography and measuring a peak area corresponding to each monomer.

In the formula (1), R₁Represents a hydrogen atom or a methyl group, R₁When it is a hydrogen atom, R₂Represents an alkyl group having 1 to 8 carbon atoms, R₁When it is methyl, R₂Represents an alkyl group having 2 to 8 carbon atoms. Examples of the alkyl group having 2 to 8 carbon atoms include an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. From the viewpoint of heat resistance, R₂Preferably an alkyl group having 2 to 4 carbon atoms, and more preferably an ethyl group.

The weight average molecular weight (hereinafter, sometimes referred to as Mw) of the (meth) acrylic resin contained in the resin layer is 50,000 to 300,000. When Mw is less than the lower limit, transparency when exposed to a high-temperature or high-temperature and high-humidity environment is insufficient, and when Mw is more than the upper limit, film formability in the production of a resin laminate cannot be obtained. The Mw of the (meth) acrylic resin is preferably 100,000 or more, more preferably 120,000 or more, and even more preferably 150,000 or more, from the viewpoint of easily improving the transparency when exposed to a high-temperature or high-temperature and high-humidity environment. From the viewpoint of film formability in the production of the 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 can be measured by Gel Permeation Chromatography (GPC) measurement.

The (meth) acrylic resin has a melt mass flow rate (hereinafter sometimes referred to as MFR.) of usually 0.1 to 20g/10 min, preferably 0.2 to 5g/10min, more preferably 0.5 to 3g/10 min, as measured at 230 ℃ under a load of 3.8 kg. When the MFR is not more than the above upper limit, the strength of the obtained film is easily improved, and therefore, it is preferably not less than the above lower limit, from the viewpoint of film forming property of the resin laminate. MFR can be measured in accordance with the method defined in JIS K7210: 1999 "test method for melt Mass Flow Rate (MFR) and melt volume flow Rate (MVR) of Plastic-thermoplastic". The poly (methyl methacrylate) -based material was measured at a temperature of 230 ℃ and under a load of 3.80kg (37.3N) as specified in JIS.

From the viewpoint of heat resistance, the (meth) acrylic resin has a glass transition temperature (Tmg) of preferably 90 ℃ or higher, more preferably 95 ℃ or higher, and still more preferably 100 ℃ or higher. The glass transition temperature can be obtained by measuring using a Differential Scanning Calorimeter (DSC) "EXSTAR DSC 6100" manufactured by SIINanotechnology Corporation under a nitrogen atmosphere at a temperature rising rate of 10 ℃/min. In the present specification, the glass transition temperature refers to the glass transition temperature (Tmg) at the midpoint.

The (meth) acrylic resin can be prepared by polymerizing the above-mentioned monomers by a known method such as suspension polymerization, emulsion polymerization, solution polymerization, bulk polymerization, or the like. At this time, MFR, Mw, VST, etc. can be adjusted to a preferable range by adding an appropriate chain transfer agent. As the chain transfer agent, a commercially available product can be suitably used. The amount of the chain transfer agent to be added may be determined as appropriate depending on the kind and ratio of the monomers, the desired characteristics, and the like.

Examples of the vinylidene fluoride resin [ which may be referred to as a vinylidene fluoride resin (F) ] contained in the resin layer include a homopolymer of vinylidene fluoride and a copolymer of vinylidene fluoride and another monomer. From the viewpoint of easily improving the transparency of the resin laminate, the vinylidene fluoride resin is preferably a copolymer of at least 1 monomer selected from the group consisting of trifluoroethylene, tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, perfluoroalkyl vinyl ether, and ethylene, and vinylidene fluoride, and/or a homopolymer of vinylidene fluoride (polyvinylidene fluoride), and more preferably polyvinylidene fluoride.

The weight average molecular weight (Mw) of the vinylidene fluoride resin is preferably 100,000 to 500,000, more preferably 130,000 to 450,000, still more preferably 150,000 to 450,000, and particularly preferably 170,000 to 400,000. When Mw is not less than the above lower limit, the transparency of the resin laminate is easily improved when the resin laminate is exposed to a high-temperature or high-temperature and high-humidity environment, and therefore, it is preferable. When Mw is not more than the above upper limit, the film forming property is easily improved, and therefore, Mw is preferable. The weight average molecular weight can be measured by Gel Permeation Chromatography (GPC) measurement.

The vinylidene fluoride resin has a melt Mass Flow Rate (MFR) of preferably 0.1 to 50g/10 min, more preferably 1 to 50g/10 min, and still more preferably 5 to 45g/10 min, as measured at 230 ℃ under a load of 3.8 kg. When the MFR is not more than the upper limit, it is preferable because the decrease in transparency is easily suppressed when the resin laminate is used for a long period of time. An MFR of not less than the above lower limit is preferable because the film forming property is easily improved. MFR can be measured in accordance with the method defined in JIS K7210: 1999 "test method for melt Mass Flow Rate (MFR) and melt volume flow Rate (MVR) of Plastic-thermoplastic".

Vinylidene fluoride resins can be industrially produced by suspension polymerization or emulsion polymerization. In the suspension polymerization method, the monomer is dispersed in the form of droplets in a medium of water using a dispersant, and the dispersion is carried out by polymerizing an organic peroxide dissolved in the monomer as a polymerization initiator, thereby obtaining a polymer in the form of particles of 100 to 300. mu.m. The suspension polymer is preferred because it is simpler in production process and superior in handling property of powder as compared with the emulsion polymer, and it does not contain an alkali metal-containing emulsifier or salting-out agent as in the case of the emulsion polymer.

The vinylidene fluoride resin may be a commercially available one. Examples of preferable commercially available products include "KF Polymer (registered trademark)" T #1300, T #1100, T #1000, T #850, W #1000, W #1100 and W #1300 "of KUREHA CORPORATION," sollef (registered trademark) 6012, 6010 and 6008 ".

The resin layer may have a single-layer or multilayer structure, and a multilayer structure is preferable from the viewpoint of multifunctionality.

In a preferred embodiment, the resin layer has a main layer (a) and a thermoplastic resin layer (B) on at least one surface of the main layer (a). The main layer (a) preferably contains the (meth) acrylic resin (M) and the vinylidene fluoride resin (F).

In a more preferred embodiment, the resin layer contains 10 to 90 mass% of a (meth) acrylic resin and 90 to 10 mass% of a vinylidene fluoride resin based on the total resin contained in the main layer (a). When the amount of the (meth) acrylic resin is less than the lower limit, sufficient transparency cannot be obtained, and when the amount of the (meth) acrylic resin is more than the upper limit, sufficient dielectric constant cannot be obtained. When the amount of the vinylidene fluoride resin is less than the lower limit, a sufficient dielectric constant cannot be obtained, and when the amount of the vinylidene fluoride resin is more than the upper limit, durability and sufficient transparency cannot be obtained.

In the main layer (a), from the viewpoint of easily improving the dielectric constant and improving the transparency of the resin laminate, the resin laminate preferably contains 30 to 60 mass% of a (meth) acrylic resin and 70 to 40 mass% of a vinylidene fluoride resin, more preferably contains 35 to 45 mass% of a (meth) acrylic resin and 65 to 55 mass% of a vinylidene fluoride resin, even more preferably contains 37 to 45 mass% of a (meth) acrylic resin and 63 to 55 mass% of a vinylidene fluoride resin, particularly preferably contains 38 to 45 mass% of a (meth) acrylic resin and 62 to 55 mass% of a vinylidene fluoride resin, and very preferably contains 38 to 43 mass% of a (meth) acrylic resin and 62 to 57 mass% of a vinylidene fluoride resin, based on the total resin contained in the main layer (a).

The main layer (a) may further contain another resin different from the (meth) acrylic resin and the vinylidene fluoride resin. When other resin is contained, the kind thereof is not particularly limited as long as the transparency of the resin laminate is not significantly impaired. From the viewpoint of the hardness and the weatherability of the resin laminate, the amount of the other resin is preferably 15% by mass or less, more preferably 10% by mass or less, and still more preferably 5% by mass or less, based on the total resin contained in the main layer (a). Examples of the other resin include polycarbonate resin, polyamide resin, acrylonitrile-styrene copolymer, methyl methacrylate-styrene copolymer, and polyethylene terephthalate. The main layer (a) may further contain another resin, but the amount of the other resin is preferably 1 mass% or less from the viewpoint of transparency, and the resin contained in the main layer (a) is more preferably only a (meth) acrylic resin and a vinylidene fluoride resin.

The content of the alkali metal in the main layer (a) is preferably 50ppm or less, more preferably 30ppm or less, further more preferably 10ppm or less, and particularly preferably 1ppm or less, based on the total resin contained in the main layer (a). When the content of the alkali metal in the main layer (a) is not more than the above upper limit, the decrease in transparency when the resin laminate is used under high temperature or high temperature and high humidity conditions for a long period of time is easily suppressed, and therefore, it is preferable. The lower limit of the content of the alkali metal in the main layer (a) is 0, and it is very preferable that the resin laminate contains substantially no alkali metal from the viewpoint of easily suppressing the decrease in transparency of the resin laminate. Here, a trace amount of an emulsifier and the like used in the production process remains in the (meth) acrylic resin and/or the vinylidene fluoride resin contained in the main layer (a). Therefore, the main layer (a) contains, for example, 0.05ppm or more of an alkali metal such as sodium or potassium derived from the remaining emulsifier. In particular, when the (meth) acrylic resin and/or vinylidene fluoride resin contained in the main layer (a) is a product obtained by emulsion polymerization, the amount of the emulsifier remaining in the resin increases, and the content of the alkali metal in the main layer (a) also increases. 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 the vinylidene fluoride resin contained in the main layer (a).

In order to control the content of the alkali metal in the resin within the above range, the amount of the compound containing the alkali metal may be reduced when the resin is polymerized, or the compound containing the alkali metal may be removed by increasing a washing step after the polymerization. The content of the alkali metal can be determined by inductively coupled plasma mass spectrometry (ICP/MS), for example. As the inductively coupled plasma mass spectrometry, for example, a sample to be measured is ashed by an appropriate method such as a high-temperature ashing melting method, a high-temperature ashing acid dissolution method, a Ca-addition ashing acid dissolution method, a combustion absorption method, a low-temperature ashing acid dissolution method, or the like, and is dissolved in an acid, and the alkali metal content is measured by inductively coupled plasma mass spectrometry while the volume of the solution is constant.

The glass transition temperature (Tmg) of the main layer (A) is preferably 50 to 100 ℃, more preferably 55 to 80 ℃, and still more preferably 55 to 70 ℃. The Tmg of the main layer (a) can be measured using a Differential Scanning Calorimeter (DSC). For example, "EXSTAR DSC 6100" manufactured by SIINANOTECOLOGY Corporation may be used as the differential scanning calorimeter, and the measurement may be performed under a nitrogen atmosphere at a temperature rising rate of 10 ℃/min to obtain the glass transition temperature. When the main layer (a) contains 1 kind of resin, the glass transition temperature of the resin is obtained, and when the main layer (a) contains 2 or more kinds of resins, the glass transition temperature of a mixture of a plurality of resins is obtained.

The thermoplastic resin layer (B) contains at least 1 thermoplastic resin. The thermoplastic resin layer (B) contains preferably 60 mass% or more, more preferably 70 mass% or more, and still more preferably 80 mass% or more of the thermoplastic resin based on the total resin contained in each thermoplastic resin layer, from the viewpoint of maintaining transparency and molding processability. The upper limit of the amount of the thermoplastic resin is 100 mass%.

The resin layer preferably satisfies the relationship of the following formula (4).

0.2≤Y/X≤15(4)

[ wherein X represents the ultimate elongation (%) at 23 ℃ and stretching of the 500 μm main layer (A) at a rate of 50mm/min, and Y represents the ultimate elongation (%) at 23 ℃ and stretching of the 500 μm thermoplastic resin layer (B) at a rate of 50mm/min ]

The above formula (4) is more preferably 0.3. ltoreq. Y/X. ltoreq.10, still more preferably 0.4. ltoreq. Y/X. ltoreq.5, and particularly preferably 0.5. ltoreq. Y/X. ltoreq.3. When the ultimate elongation of the main layer (a) and the ultimate elongation of the thermoplastic resin layer (B) satisfy the relationship of the above formula (4), the followability is improved, and the occurrence of appearance defects such as cracking, wrinkling, cloudiness, and the like at the time of bending the resin laminate can be more effectively suppressed. The formula (4) can be adjusted to a predetermined range by adjusting the types and contents of the resin and the additive contained in the main layer (a) and the thermoplastic resin layer (B), for example, by adding the same or similar resins to each other to the main layer (a) and the thermoplastic resin layer (B).

The ultimate elongations X and Y (%) can be calculated by: the tensile test was carried out under the following conditions in accordance with JIS K-7161, and the distance (mm) between chucks at the time of occurrence of cracks or fractures in the resin sheet constituting the main layer (a) or the thermoplastic resin layer (B) was read and calculated by using the following formula (a). The tensile test under the following conditions can be carried out, for example, by measuring a resin sheet having a width of 1cm, a length of 10cm and a thickness of 500 μm using a tensile tester manufactured by Instron corporation as an apparatus.

Ultimate elongation (%) (distance between chucks at the time of occurrence of crack/fracture-distance between chucks initially)/distance between chucks initially × 100 (a)

(Condition)

The device comprises the following steps: tensile testing machine

Test temperature: 23 deg.C

Stretching speed: 50mm/min

Resin sheet material: the thickness is 500 μm

Examples of the thermoplastic resin contained in the thermoplastic resin layer (B) include the (meth) acrylic resin (M), polycarbonate resin, and cycloolefin resin. These thermoplastic resins may be used alone or in combination of two or more. When the thermoplastic resin layer (B) contains the (meth) acrylic resin (M), the relationship of the formula (3) is easily satisfied, and the thermoplastic resin layer (B) preferably has good adhesion to the main layer (a). Further, the polycarbonate resin may not satisfy the relationship of the above formula (4) because of its large ultimate elongation. Therefore, when a polycarbonate resin is used, it is preferable to use a polymer alloy of a resin capable of reducing the tensile elongation Y and a polycarbonate resin (hereinafter referred to as a PC alloy), for example, an alloy of a polycarbonate resin and a (meth) acrylic resin, a polystyrene resin, or the like.

Examples of the polycarbonate resin include polymers obtained by a phosgene method in which various dihydroxy diaryl compounds are reacted with phosgene, or a transesterification method in which a dihydroxy diaryl compound is reacted with a carbonate ester such as diphenyl carbonate, and specifically, a polycarbonate resin produced from 2, 2-bis (4-hydroxyphenyl) propane (generally referred to as bisphenol a).

Examples of the dihydroxydiaryl compound include bis (hydroxyaryl) alkanes such as bis (4-hydroxyphenyl) methane, 1-bis (4-hydroxyphenyl) ethane, 2-bis (4-hydroxyphenyl) butane, 2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2-bis (4-hydroxyphenyl-3-methylphenyl) propane, 1-bis (4-hydroxy-3-tert-butylphenyl) propane, 2-bis (4-hydroxy-3-bromophenyl) propane, 2-bis (4-hydroxy-3, 5-dibromophenyl) propane and 2, 2-bis (4-hydroxy-3, 5-dichlorophenyl) propane, in addition to bisphenol A, Bis (hydroxyaryl) cycloalkanes such as 1, 1-bis (4-hydroxyphenyl) cyclopentane and 1, 1-bis (4-hydroxyphenyl) cyclohexane, dihydroxydiaryl ethers such as 4,4 '-dihydroxydiphenyl ether and 4, 4' -dihydroxy-3, 3 '-dimethyldiphenyl ether, dihydroxydiaryl sulfides such as 4, 4' -dihydroxydiphenyl sulfide, dihydroxydiaryl sulfoxides such as 4,4 '-dihydroxydiphenyl sulfoxide and 4, 4' -dihydroxy-3, 3 '-dimethyldiphenyl sulfoxide, dihydroxydiaryl sulfones such as 4, 4' -dihydroxydiphenyl sulfone and 4,4 '-dihydroxy-3, 3' -dimethyldiphenyl sulfone.

These may be used alone or in combination of 2 or more, and piperazine, dipiperidinohydroquinone, resorcinol, 4 '-dihydroxybiphenyl (4, 4' -dihydroxydiphenyl) and the like may be mixed and used.

The dihydroxyaryl compound may be used in combination with a 3-or more-membered phenol compound as shown below. Examples of the 3-or more-membered phenol include phloroglucinol, 4, 6-dimethyl-2, 4, 6-tris- (4-hydroxyphenyl) -heptene, 2,4, 6-dimethyl-2, 4, 6-tris- (4-hydroxyphenyl) -heptane, 1,3, 5-tris- (4-hydroxyphenyl) -benzene, 1,1, 1-tris- (4-hydroxyphenyl) -ethane, and 2, 2-bis- [4, 4- (4, 4' -dihydroxydiphenyl) -cyclohexyl ] -propane.

Examples of the polycarbonate resin other than the above-mentioned polycarbonate resin include polycarbonates synthesized from isosorbide and an aromatic diol. An example of the polycarbonate is DURABIO (trademark registered) manufactured by Mitsubishi chemical corporation.

As the Polycarbonate resin, commercially available products can be used, and examples thereof include "CALIBER (registered trademark) 301-4, 301-10, 301-15, 301-22, 301-30, 301-40, SD2221W, SD2201W, TR 2201" manufactured by Sumika Styron Polycarbonate Limited.

The PC alloy can be formed from such a polycarbonate resin and a resin having compatibility with the polycarbonate resin.

Examples of the preferable commercially available PC alloy include SD POLYCA (registered trademark) manufactured by Sumika Styron Polycarbonate Limited, PCX-6648, PCX-6630, PCX-6684, PCX-6680, Iupilon (registered trademark) manufactured by Mitsubishi Engineering-Plastics Corporation, KH4210UR, KH3310UR, KH3410UR, KH3520UR, KS3410UR and KS 0 2410 UR.

The glass transition temperature of the thermoplastic resin layer (B) is preferably 80 to 180 ℃, more preferably 90 to 150 ℃, and further preferably 100 to 140 ℃. When the thermoplastic resin layer (B) contains 1 kind of thermoplastic resin, the glass transition temperature of the resin is obtained, and when the thermoplastic resin layer (B) contains 2 or more kinds of thermoplastic resins, the glass transition temperature of a mixture of a plurality of kinds of resins is obtained. The glass transition temperature can be measured using a Differential Scanning Calorimeter (DSC).

In a preferred embodiment, the thickness of the main layer (a) is larger than the thickness of the thermoplastic resin layer (B). In this case, if the Tmg of the main layer (a) is higher than the Tmg of the thermoplastic resin layer (B), the flexibility of the main layer (a) having a large thickness with respect to the molding temperature becomes better, and the resin laminate becomes easy to be molded into a curved surface, which is preferable.

The thermoplastic resin layer (B) may contain other resins (for example, thermosetting resins such as fillers and resin particles) other than the thermoplastic resin in order to improve the strength, elasticity, and the like of the thermoplastic resin layer. In this case, the amount of the other resin is preferably 40% by mass or less, more preferably 30% by mass or less, and further more preferably 20% by mass or less, based on the total resin contained in each thermoplastic resin layer. The lower limit of the amount of the other resin is 0 mass%.

In a preferred embodiment, the resin layer has a main layer containing a (meth) acrylic resin and thermoplastic resin layers (B-1) and (B-2) laminated on both surfaces of the main layer. The thermoplastic resin layers (B-1) and (B-2) may contain the same thermoplastic resin or different thermoplastic resins. From the viewpoint of preventing appearance defects from occurring during bending, it is preferable that the thermoplastic resin layers (B-1) and (B-2) contain the same thermoplastic resin.

The thermoplastic resin layers (B-1) and (B-2) are preferably (meth) acrylic resin layers or PC alloy layers, because the resin laminate is excellent in transparency, surface hardness, and molding processability, and the occurrence of appearance defects is easily suppressed even when molded into a shape having a large curvature (a small curvature radius of a curved portion).

Hereinafter, one embodiment of the present invention in which the thermoplastic resin layers (B-1) and (B-2) are (meth) acrylic resin layers will be described. In this embodiment, the thermoplastic resin layers (B-1) and (B-2) contain 1 or more kinds of (meth) acrylic resins. The thermoplastic resin layers (B-1) and (B-2) contain preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more of a (meth) acrylic resin based on the total resin contained in each thermoplastic resin layer, from the viewpoint of molding processability.

Examples of the (meth) acrylic resin include the (meth) acrylic resin (M). The (meth) acrylic resin contained in the thermoplastic resin layers (B-1) and (B-2) may be the same as or different from the (meth) acrylic resin contained in the main layer (A).

The weight average molecular weight (Mw) of the (meth) acrylic resin is preferably 50,000 to 300,000, more preferably 70,000 to 250,000, from the viewpoint of good moldability and easy improvement of mechanical strength. The weight average molecular weight can be measured by Gel Permeation Chromatography (GPC) measurement.

In this embodiment, the thermoplastic resin layers (B-1) and (B-2) may further contain 1 or more kinds of thermoplastic resins other than the (meth) acrylic resin. As the thermoplastic resin other than the (meth) acrylic resin, a thermoplastic resin compatible with the (meth) acrylic resin is preferable. Specifically, a methyl methacrylate-styrene-maleic anhydride copolymer (for example, "RESISFY" manufactured by the electrochemical industry) and a methyl methacrylate-methacrylic acid copolymer (for example, "ALTUMALS HT 121" manufactured by Arkema) may be mentioned. From the viewpoint of heat resistance, the glass transition temperature of the thermoplastic resin other than the (meth) acrylic resin is preferably 80 to 180 ℃, more preferably 90 to 150 ℃, and still more preferably 100 to 140 ℃. From the viewpoint of heat resistance and surface hardness, it is preferable that the thermoplastic resin layers (B-1) and (B-2) do not substantially contain a vinylidene fluoride resin.

Next, another embodiment of the present invention in which the thermoplastic resin layers (B-1) and (B-2) are PC alloy layers will be described below. In this embodiment, the thermoplastic resin layers (B-1) and (B-2) contain 1 or more kinds of PC alloys. From the viewpoint of impact resistance, the thermoplastic resin layers (B-1) and (B-2) contain preferably 60 mass% or more, more preferably 70 mass% or more, and still more preferably 80 mass% or more of the PC alloy based on the total resin contained in each thermoplastic resin layer.

In this embodiment, the weight average molecular weight (Mw) of the PC alloy is preferably 25,000 to 60,000, more preferably 30,000 to 50,000, from the viewpoint of easily improving impact resistance and moldability. The weight average molecular weight can be measured by Gel Permeation Chromatography (GPC) measurement.

In this embodiment, the PC alloy contained in the thermoplastic resin layers (B-1) and (B-2) preferably has a thickness of 1 to 100cm when measured at a temperature of 275 ℃ and a load of 1.2kg³10 minutes, more preferably 2 to 80cm³A time of 10 minutes, more preferably 3 to 40cm³10 minutes, particularly preferably 4 to 20cm³Melt volume flow rate (hereinafter, also referred to as MVR.) of 10 minutes. When the MVR is not less than the above lower limit, the fluidity is sufficiently high, and molding processing is easy in melt coextrusion molding or the like, and appearance defects are less likely to occur, which is preferable. When the MVR is not more than the upper limit, mechanical properties such as strength of the PC alloy layer are easily improved, and therefore, it is preferable.

MVR can be measured under a load of 1.2kg at 275 ℃ in accordance with JIS K7210.

In this embodiment, the thermoplastic resin layers (B-1) and (B-2) may further contain 1 or more kinds of thermoplastic resins other than the PC alloy. As the thermoplastic resin other than the PC alloy, a thermoplastic resin compatible with the resin contained in the PC alloy is preferable.

At least 1 of the main layer (a) and the thermoplastic resin layer (B) in the resin laminate of the present invention may further contain various additives that are generally used, within a range that does not inhibit the effects of the present invention. Examples of the additives include colorants such as stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, foaming agents, lubricants, mold release agents, antistatic agents, flame retardants, polymerization inhibitors, flame retardant aids, reinforcing agents, nucleating agents, and bluing agents.

Examples of the colorant include a compound having an anthraquinone skeleton, a compound having a phthalocyanine skeleton, and the like. Among these, compounds having an anthraquinone skeleton are preferable from the viewpoint of heat resistance.

When at least 1 of the main layer (a) and the thermoplastic resin layer (B) further contains a colorant, the content of the colorant in each layer can be appropriately selected depending on the purpose, the kind of the colorant, and the like. When a bluing agent is used as the colorant, the content thereof may be about 0.01 to 10ppm based on the total resin contained in each layer containing the bluing agent. The content is preferably 0.01ppm or more, more preferably 0.05ppm or more, further preferably 0.1ppm or more, and further preferably 7ppm or less, more preferably 5ppm or less, further preferably 4ppm or less, and particularly preferably 3ppm or less. As the bluing agent, known substances can be suitably used, and examples thereof include MACROLEX (registered trademark) Blue RR (manufactured by Bayer), MACROLEX (registered trademark) Blue3R (manufactured by Bayer), Sumiplast (registered trademark) Violet B (Sumika Chemtex co., ltd.) and Polysynthren (registered trademark) Blue RLS (manufactured by Clariant), dialesin Violet D, dialesin Blue G and dialesin Blue N (manufactured by mitsubishi chemical corporation) (trade names, respectively).

The ultraviolet absorber is not particularly limited, and various conventionally known ultraviolet absorbers can be used. For example, an ultraviolet absorber having a maximum absorption at 200 to 320nm or 320 to 400nm is mentioned. Specific examples thereof include triazine-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzoate-based ultraviolet absorbers and cyanoacrylate-based ultraviolet absorbers. As the ultraviolet absorber, 1 kind of these ultraviolet absorbers may be used alone, or 2 or more kinds may be used in combination. From the viewpoint of more effectively protecting against damage caused by ultraviolet rays, it is also preferable to use at least 1 ultraviolet absorber having a maximum absorption at 200 to 320nm and at least 1 ultraviolet absorber having a maximum absorption at 320 to 400nm in combination. As the ultraviolet absorber, commercially available products can be used, and examples thereof include "Kemisorb 102" (2, 4-bis (2, 4-dimethylphenyl) -6- (2-hydroxy-4-N-octyloxyphenyl) -1,3, 5-triazine manufactured by CHEMICPRO KASEI KAISHA, LTD.) (absorbance of 0.1), "ADK STAB LA-F70" (2,4, 6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3, 5-triazine manufactured by ADEKA (absorbance of 0.6), "ADK STABLA-31, LA-31RG, LA-31G" (2, 2' -methylenebis (4- (1,1,3, 3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol) (absorbance of 0.2); and "C, "ADK STAB LA-46" (2- (4, 6-diphenyl-1, 3, 5-triazin-2-yl) -5- (2- (2-ethylhexanoyloxy) ethoxy) phenol, manufactured by ADEKA K.) (absorbance: 0.05) or "Tinuvin 1577" (2, 4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -1,3, 5-triazine, manufactured by BASF Japan) (absorbance: 0.1) may be used. The absorbance of the exemplified ultraviolet absorber was the absorbance at 380 nm. The absorbance can be determined by: the ultraviolet absorber was dissolved in chloroform at a concentration of 10mg/L, and the concentration was measured using a spectrophotometer (e.g., spectrophotometer U-4100 manufactured by HITACHI).

When at least 1 of the main layer (a) and the thermoplastic resin layer (B) further contains an ultraviolet absorber, the content of the ultraviolet absorber in each layer can be appropriately selected depending on the purpose, the kind of the ultraviolet absorber, and the like. For example, the content of the ultraviolet absorber can be about 0.005 to 2.0 mass% based on the total resin contained in each layer containing the ultraviolet absorber. 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 of easily improving the ultraviolet absorption effect, it is preferable that the content of the ultraviolet absorber is not less than the lower limit and not more than the upper limit, because a change in the color tone (for example, the yellow index YI) of the resin laminate is easily prevented. For example, the above-mentioned commercially available products "ADK STAB LA-31, LA-31RG and LA-31G" are preferably used in the above-mentioned amounts.

In another embodiment of the present invention, when the thermoplastic resin layers (B-1) and (B-2) are PC alloy layers and the ultraviolet absorber is contained in an amount of 0.005 to 2.0 mass% based on the total resin contained in each thermoplastic resin layer, a resin laminate excellent in light resistance can be easily obtained, which is preferable.

From the viewpoint of durability of the resin laminate, the thickness of the resin layer 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 and molding processability, the thickness of the resin layer is preferably 2000 μm or less, more preferably 1500 μm or less, and still more preferably 1000 μm or less. The thickness of the resin layer can be measured by a digital micrometer (digital micrometer).

The thickness of the main layer (a) is preferably 100 μm or more, more preferably 200 μm or more, and even more preferably 300 μm or more, from the viewpoint of the durability and dielectric constant of the resin laminate. From the viewpoint of transparency and moldability, the thickness of the main layer (a) is preferably 1500 μm or less, more preferably 1200 μm or less, and still more preferably 1000 μm or less. The thickness of the main layer (a) can be determined using a digital microscope.

The thickness of the thermoplastic resin layer (B) is preferably 10 μm or more, more preferably 30 μm or more, and still more preferably 50 μm or more, from the viewpoint of durability of the resin laminate. From the viewpoint of moldability and dielectric constant, each of the particle sizes is preferably 200 μm or less, more preferably 175 μm or less, and still more preferably 150 μm or less. The thickness of the thermoplastic resin layer can be measured using a digital microscope.

The resin layer can be produced by a conventional method. For example, a resin layer having a main layer (a) containing a (meth) acrylic resin and a vinylidene fluoride resin, and thermoplastic resin layers (B-1) and (B-2) laminated on both surfaces of the main layer (a) can be produced by the following method.

The main layer (A) can be produced from a resin composition (A) comprising a (meth) acrylic resin and a vinylidene fluoride resin, and the thermoplastic resin layers (B-1) and (B-2) can be produced from the resin compositions (B-1) and (B-2), respectively. The resin compositions (B-1) and (B-2) may contain at least the resins forming the thermoplastic resin layers (B-1) and (B-2), and may contain 2 or more components such as a resin and an optional additive, or may be 1 resin alone.

The resin composition (a) can be obtained by kneading a (meth) acrylic resin and a vinylidene fluoride resin. The kneading can be carried out, for example, by a method comprising a step of melt-kneading at a temperature of 150 to 350 ℃ and a shear rate of 10 to 1000/sec.

The temperature at the time of melt kneading is preferably 150 ℃ or higher because the resin can be sufficiently melted, and is preferably 350 ℃ or lower because pyrolysis of the resin is easily suppressed. Further, when the shear rate in the melt kneading is 10/sec or more, the resin is easily sufficiently kneaded, and therefore, it is preferable that the shear rate is 1000/sec or less, since the decomposition of the resin is easily suppressed.

In order to obtain a resin composition in which the respective components are more uniformly mixed, the melt kneading is carried out at a temperature of preferably 180 to 300 ℃, more preferably 200 to 300 ℃, and at a shear rate of preferably 20 to 700/sec, more preferably 30 to 500/sec.

As the apparatus for melt kneading, a usual mixer or kneader can be used. Specific examples thereof include a single-screw kneader, a twin-screw kneader, a multi-screw extruder, a Henschel mixer, a banbury mixer, a kneader, and a roll mill. When the shearing rate is increased within the above range, a high shearing apparatus or the like may be used.

The resin compositions (B-1) and (B-2) can be produced by, for example, melt kneading at the above-mentioned temperature and shear rate, in the same manner as the resin composition (A). For example, when the thermoplastic resin layers (B-1) and (B-2) contain 1 type of thermoplastic resin, the resin layer can be obtained by melt extrusion as described later without melt kneading in advance.

The resin layer having the main layer (a) and the thermoplastic resin layers (B-1) and (B-2) respectively present on both sides of the main layer (a) as a preferred embodiment of the present invention can be produced by producing each of the layers (a), (B-1) and (B-2) from the resin compositions (a), (B-1) and (B-2) by, for example, melt extrusion molding, solution casting film forming method, hot press method, injection molding method, etc., and bonding them together through, for example, an adhesive or bonding agent; the resin compositions (A), (B-1) and (B-2) may be produced by laminating and integrating them by melt coextrusion molding. In the case of producing a resin layer by lamination, in the production of each layer, an injection molding method and a melt extrusion molding method are preferably used, and a melt extrusion molding method is more preferably used.

The melt coextrusion molding is, for example, the following molding method: the resin composition (a) and the resin compositions (B-1) and (B-2) are fed into 2 or 3 single-screw or twin-screw extruders, respectively, and melt-kneaded, and then the main layer (a) formed from the resin composition (a) and the thermoplastic resin layers (B-1) and (B-2) are laminated and integrated via a feed block die, a multi-manifold die, and the like, and extruded. When the resin compositions (B-1) and (B-2) are the same, the thermoplastic resin layers (B-1) and (B-2) can be formed by dividing 1 composition obtained by melt-kneading in 1 extruder into 2 parts via a feedblock die or the like. The obtained resin layer is preferably cooled and cured by, for example, a roller unit.

[ hard coating layer ]

The resin laminate of the present invention includes a hard coat layer laminated on at least one surface (front surface or back surface) of the resin layer. From the viewpoint of durability and surface hardness of the resin laminate, the hard coat layer is preferably laminated on at least the surface side of the resin layer, more preferably on both surfaces of the resin layer. In addition, the surface of the resin layer refers to the viewing side of the image display device.

The hard coat layer satisfies the following relationships (1) to (3).

20≤L_PET≤130 (1)

0.4≤L_HC/L_PMMA≤1.5 (2)

1≤T_HC≤30 (3)

[ in the formula, L_PETThe ultimate elongation (%) L, at 140 ℃ and 50mm/min, of a laminate comprising a substrate of 75 μm polyethylene terephthalate and the hard coat layer on one side of the substrate_HCThe maximum elongation (%) L, when a laminate comprising a substrate of 500 μm polymethyl methacrylate and the hard coat layer on one surface of the substrate was stretched at 100 ℃ and 50mm/min_PMMAThe maximum elongation (%) T of a 500 μm substrate made of polymethyl methacrylate at 100 ℃ and at a rate of 50mm/min is shown_HCThe film thickness of the hard coat layer is shown.]

In the resin laminate of the present invention, since the hard coat layer satisfies the relationships of the above-described formulae (1) to (3), the occurrence of appearance defects such as cracking, wrinkles, and white turbidity can be effectively suppressed or prevented when the resin laminate is subjected to bending processing. In particular, even when the molded article is formed into a shape having a large curvature (a shape having a small radius of curvature of the curved surface portion), the occurrence of appearance defects can be effectively suppressed or prevented.

The aforementioned formula (1) is preferably 25. ltoreq.L_PET110, more preferably 30L_PET100 or less, more preferably 30 or less L_PETLess than or equal to 80. When the lower limit is not less than the above-described lower limit, the occurrence of cracking and clouding during bending can be more effectively suppressed, and when the upper limit is not more than the above-described upper limit, the occurrence of wrinkles during bending can be more effectively suppressed.

In the above formula (1), L_PETCan be calculated by the following way: the tensile test was carried out according to JIS K-7161 under the following conditions, and the distance (mm) between chucks at the time of occurrence of cracks or fractures in the hard coat layer was measured and calculated by using the following formula (B). In the tensile test under the following conditions, for example, a tensile tester manufactured by Instron corporation can be used as the apparatus. Further, as the laminate, a 75 μm easy adhesion treated PET film [ LUMIRROR (registered trademark) U34#100 manufactured by TORAY K.K. ]]A5 μm hard coat layer was laminated on one surface of the substrate to obtain a sheet.

Ultimate elongation (%) (distance between chucks at the time of occurrence of crack/fracture-distance between chucks initially)/distance between chucks initially × 100 (B)

(Condition)

The device comprises the following steps: tensile testing machine

Test temperature: 140 deg.C

Stretching speed: 50mm/min

A laminate: a sheet comprising a 75 μm easy adhesion treated PET film substrate and a hard coat layer laminated on one surface of the substrate and having a thickness of 1 to 30 μm

The ultimate elongation L is_PETThe time point at which cracks or fractures occur in the hard coat layer of the laminate can be calculated as a reference, and cracks or fractures may not occur in the PET film as the base material at this time point.

The aforementioned formula (2) is preferably 0.6. ltoreq.L_HC/L_PMMA1.4 or less, more preferably 0.8 or less L_HC/L_PMMA1.3 or less, and more preferably 0.9 or less L_HC/L_PMMALess than or equal to 1.3. When the formula (2) is in the above range, the occurrence of appearance defects such as cracking, wrinkling, and white turbidity of the resin laminate during bending can be more effectively suppressed.

In the above formula (2), for L_HCFor L, the following laminate (HC) was used_PMMAThe following laminate (PMMA) was used, and a tensile test was performed under the following conditions in accordance with JIS K-7161, and the distance (mm) between chucks at the time point when the resin laminate itself was broken was read and calculated by using the following formula (C). In the tensile test under the following conditions, for example, a tensile tester manufactured by Instron corporation can be used as the apparatus. As the laminate (HC), PMMA having a thickness of 500 μm [ e carbon Sheet co., ltd., technollloy (registered trademark) S000 can be used, for example]As the laminate (PMMA), for example, PMMA [ Escorbo Sheet Co., Ltd., TECHNOLOY S000 (registered trademark) manufactured by Ltd., having a thickness of 500 μm can be used]A sheet.

Maximum elongation (%) - (distance between chucks at break-distance between chucks)/distance between chucks x 100 (C)

(Condition)

The device comprises the following steps: tensile testing machine

Test temperature: 100 deg.C

Stretching speed: 50mm/min

Laminate (HC): a sheet obtained by laminating a hard coating layer with the thickness of 1-30 mu m on one surface of a PMMA substrate with the thickness of 500 mu m

Laminate (PMMA): PMMA sheet with thickness of 500 μm

Note that, for the maximum elongation L_HCThe time point at which the laminate itself breaks can be calculated as a reference, and before the PMMA substrate breaks, cracks or fractures may occur in the hard coat layer or the hard coat layer may also break.

The hard coat layer may be laminated on at least one surface of the resin layer, but is preferably laminated on both surfaces of the resin layer from the viewpoint that the resin laminate is likely to exhibit shape stability even when exposed to a severe environment.

Hard coatingThickness of layer (T)_HC) Is 1 to 30 μm, preferably 2 to 25 μm, more preferably 2 to 20 μm, and further preferably 3 to 10 μm. When the thickness of the hard coat layer is not less than the above lower limit, the surface hardness can be increased, and when the thickness is not more than the above upper limit, the occurrence of appearance defects such as cracking of the hard coat layer during bending can be suppressed. When the hard coat layers are laminated on both surfaces of the resin laminate, the thickness of each hard coat layer may be different or the same.

The hard coat layer is formed from a cured product of the curable composition. The curable composition is not particularly limited as long as it can form a hard coat layer satisfying the above formulas (1) to (3), and it contains a curable compound as an essential component and may contain, for example, additives such as a curing catalyst, conductive particles, a solvent, a leveling agent, a stabilizer, an antioxidant, and a colorant as needed. When the hard coat layers are laminated on both sides of the resin layer, the curable compositions constituting the hard coat layers may be the same or different. The types and contents of the compounds and additives contained in the curable composition constituting the hard coat layer can be adjusted to the ranges shown by the respective formulae (1) to (3) by appropriately adjusting the types and contents.

Examples of the curable compound include acrylate compounds such as polyfunctional acrylate compounds; urethane acrylate compounds such as polyfunctional urethane acrylate compounds; epoxy acrylate compounds such as polyfunctional epoxy acrylate compounds; and alkoxysilane compounds such as carboxyl-modified epoxy acrylate compounds, polyester acrylate compounds, copolymer acrylate compounds, alicyclic epoxy resins, glycidyl ether epoxy resins, vinyl ether compounds, oxetane compounds, alkoxysilanes, and alkylalkoxysilanes. Among these, from the viewpoint of easy formation of a hard coat layer satisfying the above formulas (1) to (3), a radical polymerization type curable compound such as a multifunctional acrylate compound, a multifunctional urethane acrylate compound, a multifunctional epoxy acrylate compound, or the like; and thermally polymerizable curable compounds such as alkoxysilanes and alkylalkoxysilanes. These curable compounds are, for example, curable compounds that are cured by irradiation with energy rays such as electron beams, radiation, ultraviolet rays, and/or curable compounds that are cured by heating, and preferably curable compounds that are cured by irradiation with at least energy rays such as electron beams, radiation, ultraviolet rays, and the like are preferred. These curable compounds may be used alone or in combination of two or more.

A compound having at least 3 (meth) acryloyloxy groups in the molecule may also be used. The (meth) acryloyloxy group means an acryloyloxy group or a methacryloyloxy group.

Examples of the compound having at least 3 (meth) acryloyloxy groups in the molecule include poly (meth) acrylates of a polyhydric alcohol having 3 or more members such as trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, glycerol tri (meth) acrylate, pentaglycerol tri (meth) acrylate, pentaerythritol tri-or tetra- (meth) acrylate, dipentaerythritol tri-, tetra-, penta-, or hexa- (meth) acrylate, tripentaerythritol tetra-, penta-, hexa-, or hepta- (meth) acrylate; a urethane (meth) acrylate having 3 or more (meth) acryloyloxy groups in a molecule, which is obtained by reacting a compound having at least 2 isocyanate groups in a molecule with a (meth) acrylate having a hydroxyl group at a ratio of the hydroxyl group to the isocyanate group being equimolar or more [ for example, a 6-functional urethane (meth) acrylate is obtained by reacting a diisocyanate with pentaerythritol tri (meth) acrylate ]; tri (meth) acrylate of tris (2-hydroxyethyl) isocyanuric acid, and the like. Although the monomers are exemplified here, these monomers may be used as they are, or those in the form of oligomers such as dimers and trimers may be used. In addition, both monomers and oligomers may also be used. These (meth) acrylate compounds may be used alone or in combination of 2 or more.

When a compound having at least 3 (meth) acryloyloxy groups in the molecule is used as the curable compound, other curable compounds such as ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and the like having 2 (meth) acryloyloxy groups in the molecule may be used in combination as necessary. The amount of the other curable compound used is usually not more than 20 parts by mass relative to 100 parts by mass of the compound having at least 3 (meth) acryloyloxy groups in the molecule.

When the curable composition is cured by ultraviolet rays, a photopolymerization initiator is preferably used as a curing catalyst. Examples of the photopolymerization initiator include benzil, benzophenone and derivatives thereof, thioxanthone, benzil dimethyl ketal, α -hydroxyalkylbenzone, hydroxyketone, aminoalkylbenzophenone, and acylphosphine oxide, and 2 or more of them may be used as necessary. The amount of the photopolymerization initiator used is usually 0.1 to 5 parts by mass per 100 parts by mass of the curable compound.

The curable composition may contain other additives. Examples of the additives include an ion scavenger, an antioxidant, a chain transfer agent, a polymerization accelerator, a sensitizer, a sensitizing aid, a light stabilizer, an adhesion promoter, a filler, a flow control agent, a plasticizer, a defoaming agent, a leveling agent, an antistatic agent, an ultraviolet absorber, and a solvent.

Examples of the filler include organic fine particles and inorganic fine particles, and inorganic fine particles are particularly preferable. Examples of the inorganic fine particles include fine particles of metal oxides such as silica, zirconia, alumina, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, Indium Tin Oxide (ITO), antimony oxide, and cerium oxide, and fine particles of metal fluorides such as magnesium fluoride and sodium fluoride, and among these, silica, zirconia, and alumina are preferably used. The hollow silica fine particles can be suitably used, and Indium Tin Oxide (ITO), tin oxide, or the like can be suitably used when antistatic property and conductivity are to be imparted.

In one embodiment, the inorganic particulate is colloidal silica. The method for synthesizing colloidal silica includes a gas phase synthesis method such as AEROSIL synthesis by pyrolysis of silicon tetrachloride, a method using water glass as a raw material, a liquid phase synthesis method such as hydrolysis of an alkoxide, and the like, and any of them can be used. Examples of commercially available products of colloidal silica include products of "organic silica sol" (organic solvent-dispersed silica sol) of Nissan chemical industry Co., Ltd and products of "high-purity organic sol" of Hibiscus chemical industry Co., Ltd. They are obtained by dispersing colloidal silica in an organic solvent.

The curable composition may contain a small amount of the above-mentioned filler from the viewpoint of surface hardness. On the other hand, from the viewpoint of curved surface formability, it is preferable not to contain a filler. That is, the content of the filler in the curable composition may be, for example, 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, further preferably 1% by mass or less, and particularly preferably 0% by mass, based on 100% by mass of the total amount of the curable composition.

The curable composition may contain a solvent for adjusting the viscosity of the curable composition, and when the curable composition contains the inorganic particles, the curable composition may contain a solvent for dispersing the inorganic particles. In the case of preparing a curable composition containing inorganic particles and a solvent, for example, the inorganic particles and the solvent are mixed, the inorganic particles are dispersed in the solvent, and then the dispersion liquid is mixed with the curable composition. In this case, commercially available inorganic particles dispersed in an organic solvent may be mixed with the curable composition. Alternatively, the curable compound and the solvent may be mixed, and then the inorganic particles may be dispersed in the mixed solution. The solvent is not particularly limited as long as it can dissolve the curable compound and can be easily volatilized after application, and when the curable composition contains inorganic particles, a solvent capable of dispersing the inorganic particles is preferable. Examples of such solvents include alcohols such as diacetone alcohol, methanol, ethanol, isopropanol, isobutanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, and 1-methoxy-2-propanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diacetone alcohol and the like; aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; water, and the like. The amount of the solvent used may be appropriately adjusted depending on the properties of the curable compound and the like.

The curable composition for forming a hard coat layer may be a commercially available composition. Examples of commercially available products include aicaautron (registered trademark) "Z-850" manufactured by AICA Kogyo co., ltd.; lioduras (registered trademark) "MOL 5000", "MOL 5100", "MOL 5200", "MOL 2112", manufactured by Toyo Ink co., ltd.; UNIDIC "ERS-958", "ESS-177", "ESS-107", "ERS-830" manufactured by DIC corporation; NEW FRONTIER "RST-402", TAISEIFINE CHEMICAL CO., manufactured by first Industrial pharmaceutical Co., Ltd., "8 KY-012C", "8 KY-052C", "8 KY-056C", "8 KY-058", "8 KY-077" and "8 KY-078" manufactured by LTD.; "UA-122P" manufactured by Ningzhou chemical industries, Ltd.

The resin laminate of the present invention can be produced by: the curable composition is applied to at least one surface of the resin layer to form a curable coating film, and then cured.

Examples of the coating method of the curable composition include a bar coating method, a microgravure coating method, a roll coating method, a flow coating method, a dip coating method, a spin coating method, a die coating method, and a spray coating method. When the curable coating film is to be cured, irradiation with energy rays, heating, and the like may be performed depending on the type of the curable composition.

Examples of the energy ray used when the curable coating film is cured by irradiation with an energy ray include ultraviolet rays, electron beams, and radiation, and conditions such as the intensity and the irradiation time thereof can be appropriately selected depending on the type of the curable composition. When the curable coating film is cured by heating, conditions such as temperature and time may be appropriately selected depending on the type of the curable composition. The heating temperature is usually 100 ℃ or lower, preferably 80 ℃ or lower, and more preferably 60 ℃ or lower so as not to deform the resin layer. When the curable composition contains a solvent, the curable coating film may be cured after application and after evaporation of the solvent, or evaporation of the solvent and curing of the curable coating film may be performed simultaneously.

[ resin laminate ]

Fig. 1 is a schematic cross-sectional view showing an example of the resin laminate of the present invention. The resin laminate 1 includes a resin layer 2, a hard coat layer 6 laminated on a front surface of the resin layer 2, and a hard coat layer 7 laminated on a rear surface of the resin layer 2. The resin layer 2 includes a main layer 3, a thermoplastic resin layer 4 laminated on the front surface side of the main layer 3, and a thermoplastic resin layer 5 laminated on the back surface side of the main layer 3.

The resin laminate of the present invention has a high dielectric constant, preferably 3.5 or more, more preferably 3.6 or more, and even more preferably 3.7 or more, and therefore can sufficiently function even when a resin laminate subjected to bending processing (sometimes referred to as a curved resin laminate) is used in a display device such as a touch panel. The dielectric constant of the resin laminate can be measured by the method described in the description of the dielectric constant of the resin layer.

In the resin laminate of the present invention, the pencil hardness on the hard coat layer side is preferably 4B or more, more preferably F or more, further preferably H or more, and particularly preferably 2H or more, and since the surface hardness is good, the scratch resistance of the surface can be improved, and even when the curved resin laminate is used as a front panel of a display device, the scratch of the screen can be effectively suppressed or prevented. The pencil hardness was measured in accordance with JIS K5600-5-4.

The resin laminate of the present invention can effectively suppress or prevent the occurrence of appearance defects such as cracking, wrinkling, and cloudiness during bending, and particularly, can effectively suppress the occurrence of appearance defects even when molded into a shape having a large curvature (a small curvature radius of a curved surface portion). Therefore, the resin laminate of the present invention can be molded even with a resin laminate having a small radius of curvature R of the curved surface portion, for example, a resin laminate having a R of 13mm or less, 10mm or less, 7mm or less, 5mm or less, 4mm or less, 3mm or less, or 2mm or less. The radius of curvature R of the curved surface portion in the resin laminate after bending is preferably 0.1mm R15 mm, more preferably 0.5mm R14 mm, still more preferably 1mm R13 mm, yet more preferably 1mm R12, particularly preferably 1mm R10 mm, and particularly preferably 1mm R7 mm. The radius of curvature R of the curved surface portion means, for example, as shown in fig. 3, the radius R of an inscribed circle 21 formed along the curved surface portion 3 in the cross section of the curved resin laminate 1. The curved surface portion may be curved in a direction (front surface direction) toward a viewing side (front surface side) of the display device, may be curved in a direction (back surface direction) toward a side (back surface side) opposite to the viewing side, and is preferably curved in a back surface direction.

The resin laminate of the present invention can effectively suppress or prevent appearance defects such as cracking, wrinkling, cloudiness, and the like during bending, and can effectively suppress appearance defects even when formed into a shape having a large curvature in a curved surface portion. Therefore, when the resin laminate of the present invention is used, even a laminate having a large bending angle (bending angle) of the curved surface portion, a resin laminate having a bending angle of preferably 10 ° or more, more preferably 30 ° or more, further preferably 60 ° or more, further more preferably 70 ° or more, and particularly preferably 80 ° or more can be molded. The curved angle of the curved surface portion means, for example, as shown in fig. 3, a central angle α of a sector formed by an end point (or start point) 22 and an end point (or end point) 23 of the curved surface portion 3 and a center point 24 of an inscribed circle in an inscribed circle 21 formed along the curved surface portion 3.

Examples of the method of bending the resin laminate include a method of performing hot press molding using a three-dimensional bending die having a predetermined radius of curvature, a hot bending method, and a vacuum molding method.

The molding processing temperature of the resin laminate of the present invention may be a temperature not lower than Tmg of the layer having the highest Tmg among the layers constituting the resin layer. In a preferred embodiment, the glass transition temperature of the main layer (A) is represented by Tmg_AAnd the glass transition temperature of the thermoplastic resin layer (B) is represented by Tmg_BThe molding temperature (T) satisfies the following relationship: tmg_A+40<T<Tmg_A+90，Tmg_B<And T. For example, the molding temperature may be 100 to 160 ℃, and more preferably 120 to 140 ℃.

Fig. 2 is a schematic cross-sectional view showing an example of the resin laminate after bending. The curved resin laminate 1 has a flat portion 8 and a curved portion 9 curved from both ends of the flat portion 8 in the back surface direction (downward in fig. 2). The curved surface portion 9 is curved so that the radius of curvature R is 0.1. ltoreq. R.ltoreq.14.

The resin laminate of the present invention has good surface hardness while suppressing appearance defects during bending, and therefore can be used as a front panel of various display devices, for example, a liquid crystal display device, an organic Electroluminescence (EL) display device, and a touch panel display device, even after bending. Further, since the curved surface shape is provided, the display device can be used as a front panel of a display device having high design, unlike a conventional flat display device.

The resin laminate of the present invention is preferably transparent when visually observed. Specifically, the resin laminate of the present invention has a total light transmittance (Tt) of preferably 85% or more, more preferably 88% or more, and still more preferably 90% or more, as measured in accordance with JIS K7361-1: 1997. The upper limit of the total light transmittance is 100%. Preferably, the resin laminate of the present invention has a total light transmittance within the above range even after exposure to a severe environment such as high temperature or high temperature and high humidity.

The thickness of the resin laminate of the present invention is preferably 100 to 1500. mu.m, more preferably 150 to 1300. mu.m, and still more preferably 200 to 1000. mu.m. When the thickness of the resin laminate is equal to or more than the above lower limit, the sheet has good rigidity and can be prevented from being deformed during pressing, and when the thickness is equal to or less than the above upper limit, the distance to the touch sensor (touchsensor) becomes short when the resin laminate is used for the front panel, and good sensitivity can be exhibited.

The resin laminate of the present invention may have at least 1 functional layer in addition to the aforementioned resin layer and the aforementioned hard coat layer. Examples of the functional layer include an antireflection layer, an antiglare layer, an antistatic layer, and an anti-fingerprint layer. These functional layers may preferably be disposed on the side of the hard coat layer opposite to the resin layer. The functional layer may be laminated via an adhesive layer, or may be a coating layer laminated by coating. As the functional layer, for example, a cured coating as described in japanese patent application laid-open No. 2013-86273 can be used.

The thickness of the functional layer may be appropriately selected depending on the purpose of each functional layer, and is preferably 1 μm or more, more preferably 3 μm or more, and even more preferably 5 μm or more from the viewpoint of easily developing the function, and is preferably 100 μm or less, more preferably 80 μm or less, and even more preferably 70 μm or less from the viewpoint of easily preventing cracking of the functional layer.

Examples

The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[ glass transition temperature (Tmg) ]

The glass transition temperature (Tmg) was measured using a Differential Scanning Calorimeter (DSC) "EXSTAR DSC 6100" manufactured by SII Nanotechnology Corporation under a nitrogen atmosphere at a temperature rising rate of 10 ℃/min.

[ content of alkali Metal ]

And (3) carrying out determination by using inductively coupled plasma mass spectrometry.

〔MFR〕

The measurement was carried out in accordance with JIS K7210: 1999 "test methods for melt Mass Flow Rate (MFR) and melt volume flow Rate (MVR) of Plastic-thermoplastic". The poly (methyl methacrylate) -based material was measured at a temperature of 230 ℃ and under a load of 3.80kg (37.3N) as specified in JIS.

〔MVR〕

The measurement was carried out under a load of 1.2kg and at 275 ℃ in accordance with JIS K7210 using "Semi-automatic Melt index apparatus 2A (Semi-auto Melt index apparatus 2A)" manufactured by Toyo Seiki Seisaku-Sho Seiki K.K.K..

[ dielectric constant ]

The resin layer or the curved resin laminate was left to stand at 23 ℃ for 24 hours in an environment with a relative humidity of 50%, and the resin layer or the resin laminate was measured at 3V and 100kHz by the self-equilibrium bridge method in this environment. For the measurement, "precision LCR meter HP 4284A" manufactured by Agilent Technologies was used.

Production example 1

98.5 parts by mass of methyl methacrylate and 1.5 parts by mass of methyl acrylate were mixed, and 0.16 part by mass of a chain transfer agent (octyl mercaptan) and 0.1 part by mass of a release agent (stearyl alcohol) were added to obtain a monomer mixture. Further, 0.036 part by mass of a polymerization initiator [1, 1-bis (t-butylperoxy) 3,3, 5-trimethylcyclohexane ] was added to 100 parts by mass of methyl methacrylate to obtain an initiator mixture. The mixture was continuously supplied to a complete mixing type polymerization reactor so that the flow ratio of the monomer mixture to the initiator mixture became 8.8:1, and polymerization was carried out under conditions of an average residence time of 20 minutes and a temperature of 175 ℃ until the average polymerization rate became 54%, to obtain a partial polymer. The obtained partial polymer was heated to 200 ℃ and introduced into a devolatilizing extruder with a vent (vent), unreacted monomers were devolatilized from the vent at 240 ℃, and the devolatilized polymer was extruded in a molten state, cooled with water, and cut to obtain a granular methacrylic resin (i).

The obtained granular methacrylic resin (i) was analyzed by pyrolysis gas chromatography under the conditions shown below, and the respective peak areas corresponding to methyl methacrylate and acrylic ester were measured. As a result, the structural unit derived from methyl methacrylate in the methacrylic resin (i) was 97.5 mass%, and the structural unit derived from methyl acrylate was 2.5 mass%.

(pyrolysis conditions)

Sample preparation: the methacrylic resin composition (target amount is 2 to 3mg) was precisely weighed, and the composition was put into the center of a cylindrical metal chamber (cell), the metal chamber was closed, and both ends were lightly pressed with a pincer to perform sealing.

A pyrolysis device: CURIE POINT PYROLYZER JHP-22 (manufactured by JASCO ANALYSIS INDUSTRY Co., Ltd.)

A metal chamber: pyrofoil F590 (manufactured by Japan analytical Industrial Co., Ltd.)

Set temperature of thermostatic bath: 200 deg.C

Setting temperature of the heat preservation pipe: 250 deg.C

Pyrolysis temperature: 590 deg.C

Pyrolysis time: 5 seconds

(analysis conditions for gas chromatography)

Gas chromatography analysis apparatus: GC-14B [ (manufactured by Shimadzu Kabushiki Kaisha ]

The detection method comprises the following steps: FID

Column: 7G 3.2 m.times.phi.3.1 mm [ (manufactured by Shimadzu corporation) ]

Filling agent: FAL-M [ (manufactured by Shimadzu Kabushiki Kaisha ]

Carrier gas: air/N₂/H₂50/100/50(kPa), 80 ml/min

Temperature rise conditions of the column: holding at 100 deg.C for 15 min, heating to 150 deg.C at 10 deg.C/min, and holding at 150 deg.C for 14 min

INJ temperature: 200 deg.C

DET temperature: 200 deg.C

The methacrylic resin composition was pyrolyzed under the above pyrolysis conditions, the generated decomposition product was measured under the above gas chromatography analysis conditions, and the peak area corresponding to methyl methacrylate (a1) and the peak area corresponding to acrylic ester (b1) detected at that time were measured. Then, from these peak areas, a peak area ratio a (═ b1/a1) was determined. On the other hand, the mass ratio of the acrylate ester unit to the methyl methacrylate unit is W under the above pyrolysis conditions₀(known) a standard of a methacrylic resin was pyrolyzed, the generated decomposition product was measured under the above-mentioned gas chromatography analysis conditions, and the peak area (a) corresponding to methyl methacrylate detected at that time was measured₀) And the peak area corresponding to the acrylate (b)₀) The peak area ratio A was determined from these peak areas₀(＝b₀/a₀). Then, the peak area ratio A is determined from the above₀And the aforementioned mass ratio W₀The coefficient f (═ W) is obtained₀/A₀)。

The peak area ratio a is multiplied by the coefficient f to obtain a mass ratio W of the acrylate ester unit to the methyl methacrylate unit in the copolymer contained in the methacrylic resin composition, and from the mass ratio W, a ratio (mass%) of the methyl methacrylate unit to a total of the methyl methacrylate unit and the acrylate ester unit and a ratio (mass%) of the acrylate ester unit to a total of the methyl methacrylate unit and the acrylate ester unit are calculated.

The resulting methacrylic resin (i) had a methyl acrylate unit ratio of 2.5 wt%, an MFR of 2g/10min, an Mw of 120,000, a glass transition temperature (Tmg) of 109 ℃, a Na content of less than 0.01ppm, and a K content of less than 0.01 ppm.

The weight average molecular weight (Mw) of the (meth) acrylic resin was measured by Gel Permeation Chromatography (GPC). In order to prepare a GPC calibration curve, a calibration curve was prepared from the elution time and the molecular weight using a methacrylic resin of Showa Denko K.K. having a narrow molecular weight distribution and a known molecular weight as a calibration reagent, and the weight average molecular weight of each resin composition was measured. Specifically, 40mg of the resin was dissolved in 20ml of Tetrahydrofuran (THF) solvent to prepare a measurement sample. As the measuring apparatus, the following measuring apparatuses were used: 2 columns "TSKgel SuperHM-H" and 1 column "SuperH 2500" manufactured by Tosoh Corporation were arranged in a serial arrangement, and an RI detector was used as a detector. The measured molecular weight distribution curve was fitted using a normal distribution function by taking the logarithm of the molecular weight on the horizontal axis, and was fitted using a normal distribution function of the following formula.

[ mathematical formula 1]

Production example 2

A granular methacrylic resin (ii) was obtained in the same manner as in production example 1 except that the amount of methyl methacrylate was changed to 97.7 parts by mass, the amount of methyl acrylate was changed to 2.3 parts by mass, and the amount of chain transfer agent was changed to 0.05 part by mass, and the content of the structural unit was measured. The structural unit derived from methyl methacrylate in the methacrylic resin (ii) was 97.0 mass%, and the structural unit derived from methyl acrylate was 3.0 mass%.

The resulting methacrylic resin (ii) had a methyl acrylate unit ratio of 3 wt%, an MFR of 0.5g/10min, an Mw of 180,000, a glass transition temperature (Tmg) of 106 ℃, a Na content of less than 0.01ppm, and a K content of less than 0.01 ppm.

In the examples, a vinylidene fluoride resin (i) having an MFR of 30g/10min, an Mw of 200,000, a Na content of 0.3ppm and a K content of 0.05ppm was used.

The weight average molecular weight (Mw) of the vinylidene fluoride resin was measured by Gel Permeation Chromatography (GPC). In order to prepare a calibration curve for GPC, a calibration curve was prepared from elution time and molecular weight using polystyrene as a standard reagent, and the weight average molecular weight of each resin was measured. Specifically, 40mg of the resin was dissolved in 20ml of an N-methylpyrrolidone (NMP) solvent to prepare a measurement sample. As the measuring apparatus, the following measuring apparatuses were used: 2 columns "TSKgel SuperHM-H" and 1 column "SuperH 2500" manufactured by Tosoh Corporation were arranged in a serial arrangement, and an RI detector was used as a detector.

Production example 3

In order to form the bluing agent into a Master Batch (MB), the methacrylic resin (ii) and the colorant are dry-blended at a ratio of 99.99:0.01, and melt-mixed at a set temperature of 250 to 260 ℃ using a single screw extruder (manufactured by Takeda plastic industries, Ltd.) having a diameter of 40mm to obtain colored master batch particles. As the colorant, a bluing agent ("Sumiplast (registered trademark) Violet B" manufactured by sutka Chemtex co., ltd.) was used.

Production example 4

First, as a material for forming the main layer (a) (intermediate layer), the methacrylic resin (ii) and the vinylidene fluoride resin (i) obtained in production example 2 and the master batch pellets prepared in production example 3 were melt-kneaded at a ratio of 39:60:1 at 250 ℃ using a 32mm twin-screw kneader (manufactured by toshiba corporation), to obtain a resin composition for the main layer (a) of the present invention. Next, a resin layer was manufactured using the apparatus shown in fig. 4. Specifically, the resin composition was melted by a 65mm single screw extruder 12 (manufactured by Toshiba machine Co., Ltd.), and 100 parts by mass of the methacrylic resin (i) as a material for forming the thermoplastic resin layers (B-1) and (B-2) were melted by 45mm single screw extruders 11 and 13 (manufactured by Hitachi Takara Shuzo Co., Ltd.). Then, they were laminated via a supply block 14 having a set temperature of 250 to 270 [ manufactured by Hitachi Takara Shuzo ], so as to have a structure represented by the above thermoplastic resin layer (B-1)/main layer (A)/thermoplastic resin layer (B-2), and extruded from a manifold die 15 [ manufactured by Hitachi Takara Shuzo, 2-3-layer distribution ] to obtain a film-shaped molten resin 16. Then, the obtained molten resin 16 in the form of a film was sandwiched between a1 st cooling roll 17 (roll temperature 100 ℃ C.) and a2 nd cooling roll 18 (roll temperature 97 ℃ C.) which were disposed to face each other, and then, while being wound around the 2 nd cooling roll 18, sandwiched between the 2 nd cooling roll 18 and a 3 rd cooling roll 19 (roll temperature 95 ℃ C.), and then, wound around the 3 rd cooling roll 19, and molded and cooled, thereby obtaining a resin layer 1 having a 3-layer structure in which the film thickness of the main layer was 300 μm and the film thickness of the thermoplastic resin layer was 100 μm. The total film thickness of the obtained resin layer 1 was 500 μm, and was visually observed to be colorless and transparent. The amount of alkali metal (Na + K) contained in the main layer (A) was determined, and found to be 0.21 ppm. The glass transition temperature (Tmg) of the midpoint of the resin used in the main layer (a) was 60 ℃. The dielectric constant of the resin layer 1 was 4.0.

Production example 5

A resin layer 2 having a 3-layer structure in which the film thickness of the main layer was 300 μm and the film thickness of the thermoplastic resin layer was 100 μm was obtained in the same manner except that the resin used for the thermoplastic resin layer in production example 4 was changed to PCX-6648 manufactured by Sumika Styron Polycarbonate Limited. MVR of PCX-6648 is 6.7cm³Mw was 54,000, a glass transition temperature (Tmg) was 121 ℃, a Na content was 0.2ppm, a K content was 0.2ppm, and a dielectric constant of resin layer 2 was 4.0 in 10 minutes.

[ ratio (Y/X) of ultimate elongation X of the main layer to ultimate elongation Y of the thermoplastic resin layer ]

(ultimate elongation X of the Main layer (A))

The resin composition for the main layer (A) was press-molded at 220 ℃ to obtain a resin sheet having a width of 1cm, a length of 10cm and a thickness of 500. mu.m, and the resin sheet was stretched at 23 ℃ and 50mm/min using a tensile tester manufactured by Instron corporation in accordance with JIS K-7161, and the distance (mm) between chucks at the time point when cracks or breaks occurred in the resin sheet was read, and the ultimate elongation X (%) of the main layer (A) was calculated by the following formula (A).

As a result, the ultimate elongation X (%) of the main layer (A) was 5.

(ultimate elongation Y of thermoplastic resin layers (B-1) and (B-2))

The ultimate elongation Y (%) of the thermoplastic resin layer was calculated in the same manner as the ultimate elongation X of the main layer (a) except that the methacrylic resin (i) or PCX-6648 manufactured by Sumika Styron Polycarbonate Limited was used instead of the resin composition used for the main layer (a). As a result, the ultimate elongation Y (%) of the thermoplastic resin layer formed from the methacrylic resin (i) was 4, and the ultimate elongation Y (%) of the thermoplastic resin layer formed from PCX-6648 was 3.

In resin layer 1, Y/X was 0.8, and in resin layer 2, Y/X was 0.6.

Production example 6

The hard coat materials described in Table 2 were applied to 75 μm PET film LUMIRROR (registered trademark) U34#100 (manufactured by TORAY K.K.) to a film thickness shown in Table 2 (5 μm, 7 μm or 36 μm), and the resultant was left to stand in an oven at 80 ℃ for 3 minutes to remove the solvent, and then UV-cured using a UV irradiation apparatus manufactured by Eye graphics as a high-pressure mercury lamp to obtain a PET film with a hard coat layer. After the UV curing, Lioduras (registered trademark) MOL5000, MOL5100, and MOL5200 were put into an oven at 140 ℃ for 10 minutes to perform post-curing.

[ Table 1]

Production example 7

A PMMA Sheet with a hard coat layer was obtained in the same manner as in production example 6, except that lumiror (registered trademark) U34#100 was replaced with 500 μm Esbar Sheet co., product Technolloy (registered trademark) S000(PMMA Sheet) manufactured by Ltd.

[ ultimate elongation L_PETMeasurement of (2)]

The hard coat layer-attached PET films obtained in production example 6 were stretched at 140 ℃ and 50mm/min in accordance with JIS K-7161 using a tensile tester manufactured by Instron, and the distance (mm) between chucks at the time of occurrence of cracks and fractures in the hard coat layer was measured to calculate the ultimate elongation L of each hard coat layer-attached PET film obtained in production example 6 using the following formula (B)_PET. The results are shown in Table 2. In Table 2, the thickness (T) of the hard coat layer is shown_HC) Described in the column of "HC thickness".

[ maximum elongation L_HCMeasurement of (2)]

The hard-coated PMMA sheets obtained in production example 7 were stretched at 100 ℃ and 50mm/min in a tensile tester manufactured by Instron corporation according to JIS K-7161, the distance (mm) between the chucks at the time point when the hard-coated PMMA sheets broke was read, and the maximum elongation L of each hard-coated PMMA sheet obtained in production example 7 was calculated from the following formula (C)_HC(%). The results are shown in Table 2.

[ maximum elongation L_PMMAMeasurement of (2)]

The PMMA Sheet with a hard coat layer of 500 μm obtained in production example 7 was replaced with a PMMA Sheet of 500 μm Esbabo Sheet Co., Ltd., TECHNOLLOY (registered trademark) S000(PMMA Sheet), and the maximum elongation L was used_HCIn the same manner, the maximum elongation L was calculated_PMMA(%). As a result, L_PMMAThe content was 250%.

[ Table 2]

[ example 1]

One surface of the resin layer 1 obtained in production example 4 was coated with AICA Kogyo co., ltd. aicaautron (registered trademark) Z-850 so that the hard coat layer became 5 μm, and the resultant was left to stand in an oven at 50 ℃ for 10 minutes to remove the solvent, and then UV-cured using a UV irradiation apparatus made by Eye graphics as a high-pressure mercury lamp, and then the other surface was coated with AICA Kogyo co., ltd. aigatron (registered trademark) Z-850 also in the same manner, thereby obtaining a resin laminate. When a bending test in which the resin laminate is bent by hot pressing at 90 ° (bending angle 90 °) at 120 to 130 ℃ using a three-dimensional bending die having a predetermined radius of curvature R is performed, the resin laminate with a hard coat layer to which a curved surface shape is imparted has an appearance including a curved surface portion and a flat portion and has no appearance defects such as cracks and wrinkles until the radius of curvature R becomes 13 mm.

[ example 2]

A resin laminate (hard coat thickness: 5 μm) was obtained in the same manner as in example 1, except that a Lioduras (registered trademark) MOL5000 manufactured by Toyo Ink co., ltd. was used in place of aicatotron (registered trademark), and after UV curing, the laminate was put into an oven at 140 ℃. As a result of the thermal bending test of the obtained resin laminate by the same method as in example 1, even when the curvature radius R was 2mm, the appearance of the resin laminate with a hard coat layer having a curved surface shape included a curved surface portion and a flat portion, and appearance defects such as cracks and wrinkles were not present.

[ example 3]

A resin laminate (hard coat thickness 5 μm) was obtained in the same manner as in example 2, except that Toyo Ink co., ltd, Lioduras (registered trademark) MOL5000 was used instead of Toyo Ink co., ltd, Lioduras (registered trademark) MOL 5100. As a result of the thermal bending test of the obtained resin laminate by the same method as in example 1, even when the curvature radius R was 2mm, the appearance of the resin laminate with a hard coat layer having a curved surface shape included a curved surface portion and a flat portion, and appearance defects such as cracks and wrinkles were not present.

[ example 4]

A resin laminate (hard coat thickness 5 μm) was obtained in the same manner as in example 2, except that Toyo Ink co., ltd, Lioduras (registered trademark) MOL5200 was used instead of Toyo Ink co., ltd, Lioduras (registered trademark) MOL 5000. As a result of the thermal bending test of the obtained resin laminate by the same method as in example 1, even when the curvature radius R was 2mm, the appearance of the resin laminate with a hard coat layer having a curved surface shape included a curved surface portion and a flat portion, and appearance defects such as cracks and wrinkles were not present.

[ example 5]

A resin laminate (hard coat thickness: 5 μm) was obtained in the same manner as in example 1, except that Lioduras (registered trademark) MOL2112 manufactured by Toyo Ink co. As a result of the thermal bending test of the obtained resin laminate by the same method as in example 1, even when the curvature radius R was 7mm, the appearance of the resin laminate with a hard coat layer having a curved surface shape included a curved surface portion and a flat portion, and appearance defects such as cracks and wrinkles were not present.

[ example 6]

A resin laminate (hard coat layer thickness: 5 μm) was obtained in the same manner as in example 1, except that the resin layer 1 was replaced with the resin layer 2. As a result of the thermal bending test of the obtained resin laminate by the same method as in example 1, even when the curvature radius R was 13mm, the appearance of the resin laminate with a hard coat layer having a curved surface shape included a curved surface portion and a flat portion, and appearance defects such as cracks and wrinkles were not present.

[ example 7]

A resin laminate (hard coat layer thickness: 5 μm) was obtained in the same manner as in example 2, except that the resin layer 1 was replaced with the resin layer 2. As a result of the thermal bending test of the obtained resin laminate by the same method as in example 1, even when the curvature radius R was 2mm, the appearance of the resin laminate with a hard coat layer having a curved surface shape included a curved surface portion and a flat portion, and appearance defects such as cracks and wrinkles were not present.

[ example 8]

A resin laminate was obtained in the same manner as in example 3, except that the film thickness of the hard coat layer was changed to 7 μm. The resin laminate with a hard coat layer, which has been given a curved surface shape until the radius of curvature R becomes 13mm, has an appearance including a curved surface portion and a flat portion, and is free from appearance defects such as cracks and wrinkles.

Comparative example 1

A resin laminate (hard coat layer thickness 5 μm) was obtained in the same manner as in example 1, except that SilFORT (registered trademark) UVHC7800FS was used in place of aicaatron (registered trademark) Z-850. When a bending test is performed under the condition that the curvature radius R is 15mm or less, appearance defects such as wrinkles and white turbidity are generated at any position of a curved surface portion and a flat portion.

Comparative example 2

A resin laminate was obtained in the same manner as in example 1 except that SilFORT (registered trademark) UVHC7800FS and ACRIT (registered trademark) 8BR-500 were mixed so that the solid content mass ratio was 60:40, instead of aicaitron (registered trademark) Z-850. When a bending test is performed under the condition that the curvature radius R is 15mm or less, appearance defects such as wrinkles and white turbidity are generated at any position of a curved surface portion and a flat portion.

Comparative example 3

A resin laminate was obtained in the same manner as in example 1, except that aiton (registered trademark) Z-850 (manufactured by ltd., ltd.) was coated on the hard coat layer so as to have a thickness of 36 μm. When a bending test is performed under the condition that the curvature radius R is 15mm or less, appearance defects such as wrinkles and white turbidity are generated at any position of a curved surface portion and a flat portion.

The pencil hardness of the resin laminates subjected to the curving treatment obtained in examples 1 to 7 and comparative examples 1 and 2 was measured in accordance with JIS K5600-5-4, and the results of the bending test are shown in table 3. In the bending test, a value of "o" indicates that the resin laminate includes a curved portion and a flat portion and that no appearance defect such as a crack or wrinkle is present, and a value of "x" indicates that an appearance defect such as a crack, wrinkle, or white turbidity is present at any portion of the curved portion and the flat portion of the resin laminate.

[ Table 3]

The resin laminates obtained in examples 1 to 7 and comparative examples 1 and 2 did not cause appearance defects such as cracking, wrinkles, and white turbidity even when the curvature radius R was small, as compared with comparative examples 1 and 2. Therefore, it was confirmed that the resin laminate of the present invention can effectively suppress or prevent the occurrence of appearance defects during molding.

Claims

1. A resin laminate comprising a resin layer having a dielectric constant of 3.5 or more and a hard coat layer laminated on at least one surface of the resin layer,

35≤L_PET≤75 (1)，

0.4≤L_HC/L_PMMA≤1.5 (2)，

1≤T_HC≤30 (3)，

in the formula, L_PETThe ultimate elongation (%) L, at 140 ℃ and at a rate of 50mm/min, when a laminate comprising a substrate of 75 μm thick comprising polyethylene terephthalate and the hard coat layer on one side of the substrate was stretched_HCThe maximum elongation (%) L at 100 ℃ and 50mm/min of a laminate comprising a substrate of polymethyl methacrylate having a thickness of 500 μm and the hard coat layer on one side of the substrate, L_PMMAThe maximum elongation (%) at 100 ℃ and at a rate of 50mm/min, T, when a substrate of polymethyl methacrylate having a thickness of 500 μm was stretched_HCRepresents a film thickness (μm) of the hard coat layer;

the resin layer has a main layer (A) and thermoplastic resin layers (B) laminated on both surfaces of the main layer (A), the main layer (A) contains a (meth) acrylic resin and a vinylidene fluoride resin,

the content of alkali metal in the main layer (A) is 50ppm or less based on the total resin contained in the main layer (A).

2. The resin laminate as set forth in claim 1, comprising a curved surface portion having a radius of curvature R of 0.1mm ≦ R ≦ 14 mm.

3. The resin laminate according to claim 1 or 2, wherein the resin layer has a main layer (a) and thermoplastic resin layers (B) laminated on both sides of the main layer (a), and satisfies the relationship of the following formula (4):

0.2≤Y/X≤15 (4)

wherein X represents the ultimate elongation (%) at 23 ℃ and stretching the main layer (A) having a thickness of 500 μm at a rate of 50mm/min, and Y represents the ultimate elongation (%) at 23 ℃ and stretching the thermoplastic resin layer (B) having a thickness of 500 μm at a rate of 50 mm/min.