JP2016107468A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate which is excellent in economical efficiency obtained by using a general-purpose material as a main raw material, is used for a substrate material or a protective material and is excellent in impact resistance, surface hardness and shape stability in a high-temperature or high-humidity environment.SOLUTION: There is provided a laminate which has at least one intermediate layer (M) between a resin layer (B) containing a polycarbonate-based resin (b1) and a resin layer (A) containing an acrylic resin (a1) and has the following characteristics (i) and (ii), in which the intermediate layer (M) is a mixture of the acrylic resin and a copolymer of an aromatic vinyl monomer, an acrylic acid ester monomer and an unsaturated dicarboxylic acid anhydride monomer. (i) The water absorption rate of the resin layer (A) and the water absorption rate of the intermediate layer after left to stand for 120 hours under a high temperature and high humidity environment of 85°C and 85%RH are defined as Wand W, respectively, W<W. (ii) The pencil hardness of the resin layer (B) and the pencil hardness of the intermediate layer determined according to JISK5600-5-4 are defined as Hand H, respectively, H<H.SELECTED DRAWING: None

Description

  The present invention relates to a laminate, and more specifically, is used as a substrate material or a protective material, and can be suitably used as a cover material for a surface protective panel of an image display device, a mobile phone, a smartphone, a tablet device, or the like. It relates to a laminate.

  Conventionally, glass has been mainly used as a cover material for image display devices. However, since glass is easily broken by impact and is heavy, substitution with a resin material has been studied. Here, the resin material is mainly required to have impact resistance, surface hardness, and shape stability in a high temperature and high humidity environment.

  Polycarbonate resin plates are transparent and have excellent impact resistance and heat resistance, so they are used for soundproofing partitions, carports, signboards, glazing materials, lighting equipment, etc. There is a drawback that it is easy to stick, and its use is limited.

  For example, Patent Document 1 discloses a resin film made of an aromatic (meth) acrylate copolymer and a polycarbonate in order to improve this drawback.

  For example, Patent Document 2 discloses a resin laminate in which a hard coat treatment is performed on a laminate in which an acrylic resin is coextruded on one surface of a polycarbonate resin.

  For example, Patent Document 3 discloses a resin plate including a methacrylic resin containing a methacrylic resin on one surface of a polycarbonate resin and an acrylic rubber particle on the other surface.

JP 2014-1267 A JP 2006-103169 A JP 2013-169693 A

  However, the resin film disclosed in Patent Document 1 is not sufficient although the surface hardness is improved to some extent. Further, the copolymerized polycarbonate used in the specific examples is a special raw material and has a problem in economical efficiency.

  In the laminate disclosed in Patent Document 2, although the surface hardness is improved to some extent, in applications in which environmental changes such as high temperature and high humidity occur, heat resistance and water absorption characteristics represented mainly by the glass transition temperature of polycarbonate resin and acrylic resin As a result, a difference in dimensional change occurs, resulting in a large warp on one surface, and there is a problem in shape stability.

  The resin plate disclosed in Patent Document 3 has improved shape stability and is effective for light weight impact, but is not impact resistant enough for practical use.

  Therefore, the object of the present invention is to improve the economics by using a general-purpose material as a main raw material, and to provide impact resistance, surface hardness, and shape stability in high-temperature and high-humidity environments used for substrate materials and protective materials. The object is to provide an excellent laminate.

The laminate of the present invention has at least one intermediate layer (M) between a resin layer (B) containing a polycarbonate resin (b1) and a resin layer (A) containing an acrylic resin (a1). The laminate is characterized by having the following characteristics (i) and (ii).
(I) When the water absorption rate of the resin layer (A) after being left in a high temperature and high humidity environment of 85 ° C. and 85% RH for 120 hours is W _A , and the water absorption rate of the intermediate layer is W _M , W _M <W _A.
When the pencil hardness _{H B} of (ii) the resin layer was measured according to JIS K5600-5-4 (B), the pencil hardness of the intermediate layer was changed to _{H M,} is _H B <H _M.

  ADVANTAGE OF THE INVENTION According to this invention, the laminated body which is excellent in impact resistance, surface hardness, and shape stability in high temperature and a humid environment can be provided, and this laminated body can be used as various board | substrate materials, protective materials, etc. Specifically, portable display devices (mobile phone terminals, smartphones, portable electronic playground equipment, personal digital assistants, tablet devices, mobile PCs, etc.) and stationary display devices (LCD TVs, LCD monitors, desktop PCs, car navigation systems, It can be suitably used for automobile instruments and the like.

  The present invention will be described in detail below.

The laminate of the present invention has at least one intermediate layer (M) between a resin layer (B) containing a polycarbonate resin (b1) and a resin layer (A) containing an acrylic resin (a1). A laminate having the following characteristics (i) and (ii):
(I) When the water absorption rate of the resin layer (A) after being left in a high temperature and high humidity environment of 85 ° C. and 85% RH for 120 hours is W _A and the water absorption rate of the intermediate layer (M) is W _M , W _M <W _A.
(Ii) The pencil hardness _{H B} of the resin layer was measured according to JIS K5600-5-4 (B), when the pencil hardness of the intermediate layer was changed to _{H M,} is _H B <H _M.

(Water absorption rate)
In the present invention, the water absorption rate is evaluated as follows. That is, after the composition constituting each layer was formed to a thickness of 1 mm, a 100 mm square test piece (n = 3) was cut out, and was first left in a temperature 23 ° C., humidity 50% RH environment for 24 hours, and then the weight was measured. then, was its value as _{W 1.} Next, each test piece was allowed to stand for 120 hours in an environment of temperature 85 ° C. and humidity 85% RH, the weight after water absorption was measured, and the value was defined as W ₂ . And the water absorption (%) was calculated | required with the following formula | equation.
(Water absorption) = (W ₂ −W ₁ ) / W ₁ × 100

In the present invention, when the water absorption rate of the resin layer (A) containing the acrylic resin (a1) is W _A and the water absorption rate of the intermediate layer (M) is W _M , it is important that W _M <W _A It is. If the water absorption W _M of the intermediate layer (M) is smaller than the water absorption W _{A of the} resin layer (A), the influence of the resin layer (A) that is susceptible to moisture in a high temperature and high humidity environment is reduced. And good shape stability can be expressed. The water absorption rate of each layer is not particularly limited, but is preferably 1.0% or less, more preferably 0.8% or less, further preferably 0.6% or less, and 0.4% or less. Particularly preferred.

(Pencil hardness)
As one index of surface hardness, it can be evaluated using pencil hardness. In the present invention, the pencil hardness was measured with a load of 750 g according to JIS K5600-5-4 on the surface to be measured.

In the present invention, when the pencil hardness _{H B} of the resin layer containing a polycarbonate-based resin (b1) (B), the pencil hardness of the intermediate layer (M) was _{H M,} important that a H B _{<H M} It is. Pencil hardness H _M of the intermediate layer (M) is greater than the pencil hardness H _B of the resin layer (B), the lower resin layer hardness (B), impaired properties of high resin layer hardness (A) And good surface hardness can be expressed as a laminate.

  About the surface at the side of the resin layer (A) of the laminated body of the present invention, the pencil hardness is preferably H or higher, more preferably 2H or higher, and particularly preferably 3H or higher. Moreover, about the surface of the hard-coat layer (C) applied to an outer surface side, it is preferable that pencil hardness is 4H or more, It is more preferable that it is 5H or more, It is especially preferable that it is 7H or more. When the pencil hardness is 4H or more, a laminate having excellent surface hardness can be provided. As for the surface of the hard coat layer (C) applied to the inner surface side, the pencil hardness is preferably F or more, and more preferably H or more. If the pencil hardness is F or more, it can function as a scratch-preventing layer for preventing the layered product from being scratched during transportation and processing within the process.

<Resin layer (A)>
The resin layer (A) is a layer containing an acrylic resin (a1).
The resin layer (A) shares the function of developing the surface hardness, heat resistance, etc., among the functions of the laminate. For this reason, although this resin layer (A) may be laminated | stacked on both surfaces of the resin layer (B) mentioned later, it is required to be laminated | stacked at least on one side. In the case of a display panel or the like, the resin layer (A) is preferably laminated on the outer surface side.

<Acrylic resin (a1)>
The acrylic resin (a1) is a resin containing as a main component a (co) polymer obtained by polymerizing a (meth) acrylic acid ester monomer unit as a main component and a derivative thereof. In the present specification, the (meth) acrylic acid ester monomer unit means an acrylic acid ester monomer unit or a methacrylic acid ester monomer unit. The monomer units configured here include methyl methacrylate, methacrylic acid, acrylic acid, benzyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, and t-butyl (meth) acrylate. 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, glycidyl (meth) acrylate, hydroxypropyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2 -Ethoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, norbornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate Rate, dicyclopentenyloxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, acrylic (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinate, maleic acid 2 -(Meth) acryloyloxyethyl, 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl hexahydrophthalate, pentamethylpiperidyl (meth) acrylate, tetramethylpiperidyl (meth) acrylate Examples thereof include dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate. These can be used alone or in combination of two or more. Examples of other monomer units that can be polymerized with these acrylic monomer units include olefin monomer units and vinyl monomer units.

Here, in the present invention, a homopolymer of methyl methacrylate or a copolymer of methyl methacrylate and methyl acrylate or ethyl acrylate can be suitably used because of its industrial availability. The stereoregularity is not particularly limited, but the three-dimensional structure of the (meth) acrylic acid ester monomer unit is preferably a syndiotactic structure because the glass transition temperature becomes higher and the heat resistance is improved. Specifically, among the triad fractions of mm, mr, and rr, those having the highest molar ratio of the rr structure can be suitably used. The triad fraction can be measured by a known method using a nuclear magnetic resonance measuring apparatus ( ¹ H-NMR).

The glass transition temperature of the resin layer (A) used in the present invention is preferably 100 to 140 ° C, more preferably 105 to 140 ° C, still more preferably 110 to 140 ° C, and 115 to 140. It is particularly preferable that the temperature is C. If the minimum of glass transition temperature is the said range, it is preferable from a heat resistant viewpoint. Moreover, if an upper limit is the said range, it is preferable from a viewpoint of the thermoformability at the time of providing a shape to a laminated body.
In the present invention, the glass transition temperature is measured using a differential scanning calorimeter at a heating rate of 10 ° C./min according to JIS K7121, but other known instrumental analyzers, for example, dynamic viscoelasticity It can also be measured with an apparatus.

  Commercially available products may be used as the acrylic resin (a1) used in the present invention. Specific examples include the product names “Acrypet” manufactured by Mitsubishi Rayon Co., Ltd., and products manufactured by Sumitomo Chemical Co., Ltd. Examples include the name “SUMIPEX” and the product name “PARAPET” manufactured by Kuraray Co., Ltd.

  Various additives and other resins can be appropriately blended in the resin layer (A) of the present invention as long as the effects of the present invention are not impaired. Examples of the additive include an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, a flame retardant, and a colorant. Examples of the other resin include methyl methacrylate-maleic anhydride copolymer.

(Antioxidant)
As the antioxidant, various commercially available products can be applied, and various types such as monophenol type, bisphenol type, polymer type phenol type, sulfur type and phosphite type can be exemplified.
Examples of monophenols include 2,6-di-tert-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-tert-butyl-4-ethylphenol, and the like. Examples of bisphenols include 2,2′-methylene-bis- (4-methyl-6-tert-butylphenol), 2,2′-methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4 '-Thiobis- (3-methyl-6-tert-butylphenol), 4,4'-butylidene-bis- (3-methyl-6-tert-butylphenol), 3,9-bis [{1,1-dimethyl- 2- {β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl} 2,4,9,10-tetraoxaspiro] 5,5-undecane and the like can be exemplified.

  Examples of the high molecular phenolic compound include 1,1,3-tris- (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris ( 3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis- {methylene-3- (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate} methane, bis { (3,3'-bis-4'-hydroxy-3'-tert-butylphenyl) butyric acid} glycol ester, 1,3,5-tris (3 ', 5'-di-tert-butyl-4 '-Hydroxybenzyl) -s-triazine-2,4,6- (1H, 3H, 5H) trione, tocopherol (vitamin E) and the like can be exemplified.

  Examples of sulfur-based compounds include dilauryl thiodipropionate, dimyristyl thiodipropionate, and distearyl thiopropionate.

Examples of the phosphite system include triphenyl phosphite, diphenylisodecyl phosphite, phenyl diisodecyl phosphite, 4,4′-butylidene-bis (3-methyl-6-tert-butylphenyl-di-tridecyl) phosphite, Crick neopentanetetrayl bis (octadecyl phosphite), tris (mono and / or di) phenyl phosphite, diisodecyl pentaerythritol diphosphite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10- Oxide, 10- (3,5-di-tert-butyl-4-hydroxybenzyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10 -Dihydro-9-oxa-10-fo Phaphenanthrene, cyclic neopentanetetraylbis (2,4-di-tert-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,6-di-tert-methylphenyl) phosphite, 2 , 2-methylenebis (4,6-tert-butylphenyl) octyl phosphite.
The said antioxidant can be used individually by 1 type or in combination of 2 or more types.

In the present invention, phenolic and phosphite-based antioxidants such as high-molecular-weight phenols are preferred in view of the effect of antioxidants, thermal stability, economy, etc. Among them, phosphite-based ones having excellent thermal decomposition resistance are preferred. Antioxidants are more preferred.
The addition amount of the antioxidant is in the range of 0.001 to 0.5 parts by mass and 0.05 to 0.3 parts by mass with respect to 100 parts by mass of the resin composition constituting the resin layer (A). It is preferable to add.

(UV absorber)
As the ultraviolet absorber, various commercially available products can be applied, and various types such as benzophenone, benzotriazole, triazine, and salicylic acid ester can be exemplified.
Examples of the benzophenone ultraviolet absorber include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-2′-carboxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-n-dodecyl. Oxybenzophenone, 2-hydroxy-4-n-octadecyloxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, 2-hydroxy-5-chlorobenzophenone, 2,4 Examples include -dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone.

Benzotriazole-based UV absorbers include hydroxyphenyl-substituted benzotriazole compounds, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-t-butylphenyl) benzotriazole 2- (2-hydroxy-3,5-dimethylphenyl) benzotriazole, 2- (2-methyl-4-hydroxyphenyl) benzotriazole, 2- (2-hydroxy-3-methyl-5-t-butylphenyl) ) Benzotriazole, 2- (2-hydroxy-3,5-di-t-amylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-t-butylphenyl) benzotriazole and the like.
Examples of the triazine ultraviolet absorber include 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol, 2- (4 , 6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyloxy) phenol and the like.
Examples of salicylic acid esters include phenyl salicylate and p-octylphenyl salicylate.
The said ultraviolet absorber can be used individually by 1 type or in combination of 2 or more types.
The addition amount of the ultraviolet absorber is in the range of 0.3 to 5.0 parts by mass and 0.5 to 2.0 parts by mass with respect to 100 parts by mass of the resin composition constituting the resin layer (A). It is preferable to add.

(Light stabilizer)
In addition to the above UV absorbers, hindered amine light stabilizers can be suitably used as light stabilizers that impart weather resistance. The hindered amine light stabilizer does not absorb ultraviolet rays like the ultraviolet absorber, but exhibits a remarkable synergistic effect when used together with the ultraviolet absorber.

(Hindered amine light stabilizer)
Examples of hindered amine light stabilizers include dimethyl succinate-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly [{6- (1,1 , 3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {{2, 2,6,6-tetramethyl-4-piperidyl} imino}], N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl-N- (1,2,2, 6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, 2- (3 , 5-Di-tert-4- Mud alkoxybenzylacetic) -2-n-butyl malonic acid bis (1,2,2,6,6-pentamethyl-4-piperidyl), and others.
The amount of the hindered amine light stabilizer added is in the range of 0.01 to 0.5 parts by mass with respect to 100 parts by mass of the resin composition constituting the resin layer (A), and 0.05 to 0.3. It is preferable to add part by mass.

<Resin layer (B)>
The resin layer (B) is a layer containing a polycarbonate resin (b1).
The resin layer (B) shares the function of developing the impact resistance, heat resistance, etc., among the functions of the laminate.

(Polycarbonate resin (b1))
As the polycarbonate resin (b1), an aromatic polycarbonate resin can be preferably used, but an aliphatic polycarbonate resin may be used. Moreover, either a homopolymer or a copolymer with another copolymerizable monomer may be used. Furthermore, the structure may be a branched structure, a linear structure, or a mixture of a branched structure and a linear structure.
As a method for producing the polycarbonate resin (b1) used in the present invention, any known method such as a phosgene method, a transesterification method, or a pyridine method may be used.

  The weight-average molecular weight of the polycarbonate resin (b1) used in the present invention is usually in the range of 10,000 to 100,000, preferably 20,000 to 40,000, particularly preferably 22,000 to 28,000. Can be used. Polycarbonate-type resin (b1) can be used individually by 1 type or in combination of 2 or more types. Here, if the weight average molecular weight is in the above range, impact resistance is ensured and extrusion moldability is also good, which is preferable.

  A commercially available product can be used as the polycarbonate resin (b1) used in the present invention. Specific examples of the aromatic polycarbonate resin include trade names “CALIBER” manufactured by Sumika Stylon Polycarbonate Co., Ltd., “ “SD POLYCA”, trade names “Iupilon” made by Mitsubishi Engineering Plastics, “NOVAREX”, trade names “Panlite” made by Teijin Limited, etc. Can be illustrated. Moreover, as a specific example of the aliphatic polycarbonate resin, a trade name “DURABIO” manufactured by Mitsubishi Chemical Corporation can be exemplified.

(Modifier)
In the present invention, the modifier used by mixing with the polycarbonate resin (b1) is used for the purpose of adjusting the glass transition temperature and melt viscosity and improving the hardness, and specifically, a specific polyester resin (p1). ) Can be exemplified.

(Specific polyester resin (p1))
The specific polyester resin (p1) has an aromatic dicarboxylic acid of 80 mol% or more as a carboxylic acid monomer (I) unit, and 40 of 1,4-cyclohexanedimethanol as a glycol monomer (B) unit. It is a polyester resin composed of structural units containing at least mol%.

Here, the carboxylic acid monomer (A) unit of the polyester resin (p1) contains 80 mol% or more of aromatic dicarboxylic acid. Here, it is preferable that the aromatic dicarboxylic acid is 80 mol% or more in the carboxylic acid monomer (A) unit because the resulting polyester resin (p1) has sufficient heat resistance and mechanical strength. From such a viewpoint, the aromatic dicarboxylic acid is more preferably contained in the carboxylic acid monomer (a) unit with a lower limit of 85 mol% or more, and an upper limit of 100 mol% or less. preferable.
The aromatic dicarboxylic acid is not particularly limited, and includes terephthalic acid, isophthalic acid, naphthalene-1,4 or 2,6-dicarboxylic acid, anthracene dicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4,4′- Examples include diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid, sodium 3-sulfoisophthalate, and the like. The aromatic dicarboxylic acid may be subjected to polymerization as its ester. There is no restriction | limiting in particular as aromatic dicarboxylic acid ester, The ester of said aromatic dicarboxylic acid is preferable, and lower alkyl ester, aryl ester, carbonate ester, acid halide, etc. are mentioned. The carboxylic acid monomer (a) unit may contain a small amount of an aliphatic dicarboxylic acid (usually in a range of less than 20 mol%). The aliphatic dicarboxylic acid is not particularly limited, and oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, sebacic acid, azelaic acid, dodecanedioic acid, dimer acid, 1,3 or 1,4-cyclohexanedicarboxylic acid An acid, cyclopentane dicarboxylic acid, 4,4'-dicyclohexyl dicarboxylic acid, etc. are mentioned. These carboxylic acid monomers (I) can be used alone or in combination of two or more.

  Next, the glycol monomer (B) unit of the polyester resin (p1) contains 40 mol% or more of 1,4-cyclohexanedimethanol. There are no particular limitations on the glycol used in the glycol monomer (b) other than the above-described components. Ethylene glycol, diethylene glycol (including by-product components), 1,2-propylene glycol, 1,3- Propanediol, 2,2-dimethyl-1,3-propanediol, trans- or -2,2,4,4-tetramethyl-1,3-cyclobutanediol, 1,4-butanediol, neopentyl glycol, 1 , 5-pentanediol, 1,6-hexanediol, 1,3-cyclohexanedimethanol, decamethylene glycol, cyclohexanediol, p-xylenediol, bisphenol A, tetrabromobisphenol A, tetrabromobisphenol A-bis (2- Hydroxyethyl ether) and the like. These glycol monomers (b) can be used alone or in combination of two or more, and can appropriately impart color tone, transparency, heat resistance, impact resistance, etc. to the polyester resin. However, ethylene glycol can be preferably used because it can provide thermal stability during molding of the resulting polyester resin and is inexpensive and easily available industrially.

  1,4-Cyclohexanedimethanol used for glycol monomer (b) mainly gives impact resistance to the resulting polyester resin (p1) and improves compatibility with polycarbonate resin (b1). It is something to be made. In addition, 1,4-cyclohexanedimethanol has two isomers, a cis type and a trans type, which may be either. Here, if content in a glycol monomer (b) unit is 40 mol% or more, the polyester resin (p1) to be obtained has a sufficient effect of imparting impact resistance, and a polycarbonate resin ( The compatibility with b1) is improved, and the transparency is hardly lowered, which is preferable. From this point of view, 1,4-cyclohexanedimethanol further preferably includes a lower limit value of 50 mol% or more in the glycol monomer (b) unit, and an upper limit value of 100 mol% or less. Is more preferable, and 80 mol% or less is more preferable.

  The polyester-based resin (p1) may be a commercially available product. Specific examples include a product name “SKYGREEN J2003” manufactured by SK Chemical Co., Ltd., a product manufactured by Eastman Chemical Co., Ltd. The name “Easter” PCTG Copolyester 24635 can be exemplified.

  The mixing mass ratio of the polycarbonate resin (b1) and the polyester resin (p1) is not particularly limited, but is preferably (b1) / (p1) = 99 to 1/1 to 99, 95 More preferably, it is -5 / 5-95, and it is still more preferable that it is 90-10 / 10-90. Since the mixed composition of both is compatible, it can be arbitrarily adjusted between the glass transition temperature of the polycarbonate-based resin (b1) and the glass transition temperature of the polyester-based resin (p1), which is preferable.

  The glass transition temperature of the resin layer (B) used in the present invention is preferably 100 to 160 ° C, more preferably 110 to 155 ° C, and further preferably 120 to 150 ° C. If the minimum of glass transition temperature is the said range, it is preferable from a heat resistant viewpoint. Moreover, if an upper limit is the said range, it is preferable from a viewpoint of the thermoformability at the time of providing a shape to a laminated body.

  In the resin composition constituting the resin layer (B) of the present invention, the above-described various additives and other resins can be appropriately blended within a range that does not impair the effects of the present invention. Examples of the additive include an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, a flame retardant, a colorant, and a hydrolysis inhibitor.

(Hydrolysis inhibitor)
Examples of hydrolysis inhibitors include phenolic compounds, carbodiimide compound monomers or polymers, and oxazoline compound monomers or polymers. In the present invention, a monomer or polymer of a carbodiimide compound can be preferably used.

  Examples of the carbodiimide compound include those having a basic structure represented by the following general formula (1).

In the general formula (1), n is an integer of 1 or more, and R represents an organic bond unit. For example, R can be either aliphatic, alicyclic, or aromatic. Moreover, n is generally selected from an appropriate integer between 1 and 50. When n is an integer of 2 or more, R of 2 or more may be the same or different.
Specific examples include bis (propylphenyl) carbodiimide, bis (dipropylphenyl) carbodiimide, poly (4,4′-diphenylmethanecarbodiimide), poly (p-phenylenecarbodiimide), poly (m-phenylenecarbodiimide), poly (tolyl). Carbodiimide), poly (diisopropylphenylenecarbodiimide), poly (methyl-diisopropylphenylenecarbodiimide), poly (triisopropylphenylenecarbodiimide), aromatic polycarbodiimide, and the like, and carbodiimide compounds can be exemplified. The said carbodiimide compound can be used individually by 1 type or in combination of 2 or more types. The polymer of the carbodiimide compound preferably has a molecular weight of 2,000 to 50,000.

  The carbodiimide compound may be a commercially available product. Specific examples thereof include trade names “Stabaxol P”, “Stabaxol P100” manufactured by Rhein Chemie GmbH, and products manufactured by Nisshinbo Chemical Co., Ltd. Names such as “Carbodilite HMV-8CA” and “Carbodilite LA-1” can be exemplified.

  The addition amount of the hydrolysis inhibitor is in the range of 0.001 to 1.0 parts by mass and 0.05 to 0.5 parts by mass with respect to 100 parts by mass of the resin composition constituting the resin layer (B). It is preferable to add a part.

<Intermediate layer (M)>
The intermediate layer (M) is a layer provided between the resin layer (B) and the resin layer (A), and controls the surface hardness, water absorption, and heat resistance in the laminate of the present invention. It plays a role.
In one embodiment, the intermediate layer (M) comprises the acrylic resin (a1), an aromatic vinyl monomer unit, a (meth) acrylic acid ester monomer unit, and an unsaturated dicarboxylic anhydride monomer unit. Is a layer containing a copolymer (a2) having a mixing mass ratio of (a1) / (a2) = 80-20 / 20-80.
Moreover, as another aspect, this intermediate | middle layer (M) is 5-80 mass% of said polycarbonate-type resin (b1), an aromatic (meth) acrylate monomer unit, and 95-20 mass% of methyl methacrylate monomer units. It is a layer which contains the copolymer (b2) which consists of and the mixing mass ratio is (b1) / (b2) = 99-65 / 1-35.

<Copolymer (a2)>
The copolymer (a2) is a copolymer having an aromatic vinyl monomer unit, a (meth) acrylic acid ester monomer unit, and an unsaturated dicarboxylic anhydride monomer unit.

  Here, as the aromatic vinyl monomer unit, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, ethylstyrene, p-tert-butylstyrene, α-methyl Examples include units derived from styrene monomers such as styrene and α-methyl-p-methylstyrene. These aromatic vinyl monomer units can be used alone or in combination of two or more. In the present invention, styrene units and α-methylstyrene units are preferred. Styrene units are preferred because they are easily available industrially and are economical, and α-methylstyrene units are preferred because they can improve the glass transition temperature.

  (Meth) acrylic acid ester monomer units include methyl methacrylate monomers such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, dicyclopentanyl methacrylate, and isobornyl methacrylate. And units derived from acrylic acid ester monomers such as methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-methylhexyl acrylate, 2-ethylhexyl acrylate, and decyl acrylate. These (meth) acrylic acid ester monomer units can be used alone or in combination of two or more. Here, in this invention, a methyl methacrylate unit can be used suitably from compatibility with an acrylic resin (a1), an external appearance, etc.

  Examples of the unsaturated dicarboxylic acid anhydride monomer unit include units derived from respective anhydride monomers such as maleic acid anhydride, itaconic acid anhydride, citraconic acid anhydride, and aconitic acid anhydride. These unsaturated dicarboxylic acid anhydride monomer units can be used alone or in combination of two or more. Here, in the present invention, a maleic anhydride unit can be preferably used in view of compatibility with the acrylic resin (a1) and transparency.

The constituent unit of the copolymer (a2) used in the present invention is preferably 45 to 85% by mass of an aromatic vinyl monomer unit, 4 to 45% by mass of a (meth) acrylic acid ester monomer unit, and an unsaturated dicarboxylic acid. Anhydride unit is 8 to 20% by mass, more preferably aromatic vinyl monomer unit is 55 to 85% by mass, (meth) acrylic acid ester monomer unit is 5 to 30% by mass, and unsaturated dicarboxylic acid anhydride is 10%. It is the range of -18 mass%.
Here, the structural unit of the copolymer (a2) can be qualitatively and quantitatively analyzed by a known method, for example, a nuclear magnetic resonance (NMR) measuring device or other instrumental analyzer.

  Here, if the aromatic vinyl monomer unit is preferably 45% by mass or more, more preferably 55% by mass or more, the thermal stability is improved, and a good appearance when mixed with the acrylic resin (a1). Is preferable, and water absorption can be reduced. The (meth) acrylic acid ester monomer unit is preferably 4% by mass or more, and more preferably 5% by mass or more, since the compatibility with the acrylic resin (a1) is improved and the transparency is improved. If the unsaturated dicarboxylic acid anhydride monomer unit is preferably 8% by mass or more, more preferably 10% by mass or more, compatibility with the acrylic resin (a1) is improved, and transparency and heat resistance are improved. Therefore, it is preferable.

  On the other hand, if the aromatic vinyl monomer unit is preferably 85% by mass or less, it is preferable because the heat resistance can be improved and the water absorption can be reduced while maintaining the miscibility with the acrylic resin (a1). If the (meth) acrylic acid ester monomer unit is preferably 45% by mass or less, more preferably 30% by mass or less, water absorption can be suppressed while ensuring compatibility with the acrylic resin (a1). preferable. Further, if the unsaturated dicarboxylic acid anhydride unit is preferably 20% by mass or less, more preferably 18% by mass or less, improvement in thermal stability and water absorption can be ensured while ensuring compatibility with the acrylic resin (a1). It is preferable because the property can be suppressed.

  The copolymer (a2) used in the present invention is a copolymerizable unit other than an aromatic vinyl monomer unit, a (meth) acrylate monomer unit, and an unsaturated dicarboxylic anhydride monomer unit. May be contained in the copolymer as long as the effect of the present invention is not impaired, and is preferably 5% by mass or less. Examples of copolymerizable units include vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, vinyl carboxylic acid monomers such as acrylic acid and methacrylic acid, N-methylmaleimide, N-ethylmaleimide, and N-butylmaleimide. Units derived from monomers such as N-alkylmaleimide monomers such as N-cyclohexylmaleimide, N-arylmaleimide monomers such as N-phenylmaleimide, N-methylphenylmaleimide and N-chlorophenylmaleimide Is mentioned. These copolymerizable units can be used alone or in combination of two or more.

  The copolymer (a2) used in the present invention preferably has a polystyrene-equivalent weight average molecular weight (Mw) of 100,000 to 200,000 as measured by gel permeation chromatography (GPC). Here, it is preferable that the weight average molecular weight (Mw) is in this range because the intermediate layer (M) obtained by mixing with the acrylic resin (a1) is excellent in moldability and appearance. From this viewpoint, a more preferable range of weight average molecular weight (Mw) is 110,000 to 180,000.

  The method for producing the copolymer (a2) used in the present invention can be produced by a known polymerization method and is not particularly limited. For example, solution polymerization, bulk polymerization, and the like can be applied, and batch, semi-batch, and continuous methods can be appropriately employed as the polymerization process. In the present invention, a batch polymerization process can be suitably used in solution polymerization because there are few by-products and molecular weight adjustment and transparency can be easily controlled.

  As the copolymer (a2) used in the present invention, a commercially available product can be used. Specific examples include trade names “Regisphi R-100”, “Regisphi R-200” and “Regisphi R-200” manufactured by Denki Kagaku Kogyo Co., Ltd. “Regisfi R-300” can be exemplified.

  The mixing mass ratio of the acrylic resin (a1) and the copolymer (a2) is (a1) / (a2) = 80-20 / 20-80. Here, if the mixing ratio of the acrylic resin (a1) and the copolymer (a2) is within the above range, the interlayer adhesion with the resin layer (A) and the resin layer (B) is excellent, and the acrylic resin While maintaining the characteristic surface hardness and transparency, it is preferable because heat resistance is improved and water absorption is suppressed. Further, when importance is attached to the surface hardness, it is preferable that (a1) / (a2) = 80 to 55/20 to 45. When importance is attached to improvement in heat resistance and suppression of water absorption, (a1) ) / (A2) = 50-20 / 50-80.

(Copolymer (b2))
The copolymer (b2) is a copolymer composed of 5 to 80% by mass of aromatic (meth) acrylate monomer units and 95 to 20% by mass of methyl methacrylate monomer units.

Here, examples of the aromatic (meth) acrylate monomer unit include phenyl (meth) acrylate and benzyl (meth) acrylate. These can be used alone or in combination of two or more. Here, in the present invention, phenyl methacrylate and benzyl methacrylate are preferable, and phenyl methacrylate is more preferable because of compatibility with the polycarbonate resin (b1).
The copolymer (b2) can contain other copolymerizable monomer units other than the aromatic (meth) acrylate monomer unit and the methyl methacrylate monomer unit, if necessary. When other monomer units are contained, it is preferably 0.1 to 10% by mass in the copolymer (b2).

  It is preferable that the aromatic (meth) acrylate monomer unit and the methyl methacrylate monomer unit are in the above ranges because compatibility with the polycarbonate resin (b1) and an effect of improving the surface hardness can be expressed. From this viewpoint, the aromatic (meth) acrylate monomer unit is more preferably 10 to 70% by mass and the methyl methacrylate monomer unit 90 to 30% by mass, and the aromatic (meth) acrylate monomer unit 25 to 25%. More preferably, it is 60 mass% and methyl methacrylate monomer unit 75-40 mass%.

  The copolymer (b2) preferably has a polystyrene-reduced weight average molecular weight (Mw) of 5,000 to 30,000 as measured by gel permeation chromatography (GPC). If the weight average molecular weight (Mw) is in this range, the compatibility with the polycarbonate resin (b1) is good, and the resulting intermediate layer (M) is excellent in moldability, surface hardness improvement effect and appearance. preferable. From this viewpoint, the range of the weight average molecular weight (Mw) is more preferably 10,000 to 28,000.

  As the copolymer (b2), a commercially available product can be used. As a specific example, a trade name “MATEBLEN H-880” manufactured by Mitsubishi Rayon Co., Ltd. can be exemplified.

  The mixing mass ratio of the polycarbonate resin (b1) and the copolymer (b2) is (b1) / (b2) = 99 to 65/1 to 35. Here, it is preferable if the mixing mass ratio is within this range because the resin layer (B) obtained is excellent in moldability, surface hardness improvement effect and appearance. From this viewpoint, it is more preferable that (b1) / (b2) = 95 to 70/5 to 30.

<Laminate>
The laminate of the present invention comprises a resin layer (A) on at least one surface of the resin layer (B), and at least one intermediate layer (M) is provided between the system resin layer (B) and the resin layer (A). It has a layer. In the present invention, a hard coat layer (C) described later can be further laminated on each layer.
Specific examples of the layer structure include (A) / (M) / (B), (A) / (M) / (B) / (M) / (A), and a hard coat layer (C). , (C) / (A) / (M) / (B), (C) / (A) / (M) / (B) / (C), (C) / (A) / (M) / ( Examples thereof include B) / (M) / (A) and (C) / (A) / (M) / (B) / (M) / (A) / (C). Here, when two or more identical classification layers are included in the layer structure, the layers may have the same composition or different compositions. In the present invention, (A) / (M) / (B), (C) / (A) / (M) / (B) and (C) / (A) / (M) / (B) / ( C) Configuration is preferred. In the case of a display panel or the like, (outer side) (C) / (A) / (M) / (B) / (C) (inner side) or (outer side) (C) / (A) / It is more preferable to arrange on (M) / (B) (inner surface side).

(Thickness of laminate)
The thickness of the laminate of the present invention is not particularly limited, but is usually 0.1 to 3.0 mm. The laminate thickness is preferably 0.1 to 1.5 mm, more preferably 0.15 to 1.2 mm.
Moreover, there exists a preferable range for this laminated body thickness also with the application use of the laminated body of this invention. For example, when applied to the front cover material of various image display devices, it is preferably 0.5 to 1.5 mm, more preferably 0.6 to 1.2 mm, and 0.7 to 1. More preferably, it is 1 mm. If it is in this range, it is preferable because it is excellent in lightness and rigidity and shape stability in a high temperature and high humidity environment. In addition, when an adhesive layer or the like is laminated on the laminate of the present invention, it is protected from dirt or scratches on the surface of glass or the like, or applied to applications that prevent scattering of broken pieces, etc. It is preferable that it is 0.6 mm, and it is more preferable that it is 0.15-0.5 mm.

  Moreover, when the total thickness of the resin layer (A), the intermediate layer (M), and the resin layer (B) is (T), the two layers obtained by adding the resin layer (A) and the intermediate layer (M) together The total thickness ratio [(A) + (M)] / (T) is preferably 0.01 or more, more preferably 0.05 or more, and further preferably 0.10 or more. preferable. When the ratio of the total thickness of the two layers is 0.01 or more, excellent surface hardness can be imparted to the laminate of the present invention. On the other hand, the upper limit is preferably 0.30 or less, more preferably 0.25 or less, and further preferably 0.20 or less. When the ratio of the total thickness of the two layers is 0.30 or less, the laminate of the present invention can be sufficiently imparted with impact resistance and shape stability in a high temperature or high humidity environment.

  Furthermore, the thickness of the resin layer (A) can be appropriately adjusted according to the thickness of the laminate of the present invention. Especially, it is preferable that it is 0.01 mm or more, it is more preferable that it is 0.02 mm or more, and it is further more preferable that it is 0.03 mm or more. If the thickness of the resin layer (A) is 0.01 mm or more, excellent surface hardness can be imparted to the laminate of the present invention. On the other hand, the upper limit is preferably 0.10 mm or less, more preferably 0.08 mm or less, and preferably 0.05 mm or less. If the thickness of the resin layer (A) is 0.10 mm or less, impact resistance and shape stability in a high temperature or high humidity environment can be sufficiently imparted to the laminate of the present invention.

(Total light transmittance)
When the total light transmittance is used as an index of transparency of the laminate of the present invention, it is preferably 85% or more, and more preferably 89% or more. The total light transmittance in the present invention is measured according to JIS K7361-1.

(Warp evaluation)
The warpage evaluation of the laminate of the present invention is performed as follows. That is, a 100 mm square test piece (n = 3) was cut out from the obtained laminate, and first left for 24 hours in a temperature 23 ° C., humidity 50% RH environment. Next, each test piece was allowed to stand for 120 hours in a temperature of 85 ° C. and a humidity of 85% RH, and then left for 24 hours in a temperature of 23 ° C. and a humidity of 50% RH. Then, the test piece was allowed to stand on a surface plate. The height from the platen at the four corners was measured as the amount of warpage, and the average value of the absolute values was evaluated. By making the environmental conditions the same before and after leaving in a high temperature and high humidity environment, only the influence under the high temperature and high humidity environment can be measured.
In the present invention, the amount of warpage is preferably 1.5 mm or less, more preferably 1.0 mm or less, further preferably 0.5 mm or less, and most preferably 0 mm. If it is in the said range, since a laminated body can be used in a wider use and environment, it is preferable.

The warpage evaluation was performed in the present invention under the conditions of a temperature of 85 ° C. and a humidity of 85% RH. However, as a high temperature and high humidity environment, conditions such as a temperature of 60 ° C., a humidity of 90% RH, a temperature of 70 ° C., a humidity of 90% RH, etc. May be used.
Examples of the method for reducing warpage include a method of forming a film so as not to impart a strain that adversely affects the production of a laminate, or a method of relaxing strain by annealing for several hours to several days in the vicinity of Tg. Specifically, it may be adjusted so as to reduce the thermal shrinkage rate under the environmental condition to be evaluated. Furthermore, it can also adjust with the application | coating thickness and kind to the front and back of the hard-coat layer (C) mentioned later.

(Impact resistance)
The impact resistance evaluation of the laminate of the present invention is performed as follows. That is, a test piece having a width of 50 mm and a length of 120 mm was cut out from the obtained laminate, and the resin layer (A) was faced upward, and a metal holder was used to hold both ends 10 mm so that the test piece was in a hollow state. did. Next, a metal ball having a weight of 133 g from a distance of 5 cm from the test piece is dropped on the center of the test piece to measure whether the test piece is broken or not. If no breakage occurs, the distance is increased by 5 cm and the same test is performed. The distance until destruction occurs is measured.

(Laminate manufacturing method)
Next, although the manufacturing method of the laminated body of this invention is demonstrated, it does not specifically limit. As a film forming method, a known method, for example, a single-screw extruder, a multi-screw extruder, a Banbury mixer, a kneader or the like has melt mixing equipment, and an extrusion casting method using a T die is a surface such as handleability and productivity. Can be suitably used. As a method for forming the laminate, a method in which a melt-kneaded resin is co-extruded with a T-die having a feed block or a multi-manifold can be suitably used. Moreover, in order to make the external appearance of a laminated body favorable, it is preferable to use the shaping | molding roll (metal elastic roll, polishing roll, etc.) by which the surface was mirror-finished.
The molding temperature in the extrusion casting method using a T die is appropriately adjusted depending on the flow characteristics and film-forming properties of the resin composition to be used, but is generally 300 ° C. or lower, preferably 230 to 270 ° C. The forming roll is generally 90 to 130 ° C, preferably 95 to 115 ° C.

  In the present invention, a single-screw extruder or a multi-screw extruder can be suitably used, but each layer extruder preferably has a vent function and a filter function. The vent function is preferable because it can be used for drying the resin composition used for each layer, removing a small amount of volatile components, and the like, and a laminate having few defects such as bubbles can be obtained. Further, there are various types of filter functions, and specific examples include a leaf disc filter, a back disc filter, a cone type filter, a candle filter, and a cylindrical filter. Among them, a leaf disk filter that can easily secure an effective filtration area is preferable. The filter function can remove foreign matters, minute gels, and the like, and a laminated body with few appearance defects can be obtained.

  The resin composition used in the present invention may be used by mixing each component in advance using a mixer such as a tumbler, V-type blender, Banbury mixer, or extruder, and each component measured at the supply port of the extruder may be used. The components may be directly supplied, or the components weighed separately may be supplied to each supply port of an extruder having two or more supply ports. Furthermore, the mixing method of various additives can use a well-known method. For example, a masterbatch in which various additives are mixed in a suitable base resin at a high concentration (typically about 3 to 60% by mass) is prepared separately, and the concentration is adjusted to the resin used. And a method of mixing various additives directly into the resin to be used.

<Hard coat layer (C)>
The hard coat layer (C) is a layer that imparts excellent surface hardness and scratch resistance to the laminate of the present invention.

(Hard coat agent)
The hard coating agent is not particularly limited in the present invention, but a hard coating agent that cures by irradiating energy beams such as an electron beam, radiation, or ultraviolet rays, or that cures by heating can be applied. In the present invention, it is preferably made of an ultraviolet curable resin from the viewpoint of molding time and productivity.
Here, specific examples of the curable resin include acrylate compounds, urethane acrylate compounds, epoxy acrylate compounds, carboxyl group-modified epoxy acrylate compounds, polyester acrylate compounds, copolymer acrylates, alicyclic epoxy resins, glycidyl ether epoxy resins, Examples include vinyl ether compounds and oxetane compounds. These curable resins can be used alone or in combination of two or more. Examples of curable resins that impart superior surface hardness include radical polymerization curable compounds such as polyfunctional acrylate compounds, polyfunctional urethane acrylate compounds, and polyfunctional epoxy acrylate compounds, and heat such as alkoxysilanes and alkylalkoxysilanes. Polymerizable curable compounds can be mentioned, and further, an organic / inorganic composite curable resin composition obtained by adding an inorganic component to the curable resin can also be used.

An organic / inorganic hybrid curable resin composition can be exemplified as a curable resin composition that imparts particularly excellent surface hardness. Examples of the organic / inorganic hybrid curable resin composition include those composed of a curable resin composition containing an inorganic component having a reactive functional group in the curable resin.
Utilizing such an inorganic component having a reactive functional group, for example, an organic / inorganic composite in which this inorganic component is copolymerized and crosslinked with a radical polymerizable monomer, so that the organic binder simply contains the inorganic component. Compared to the system curable resin composition, it is preferable because curing shrinkage hardly occurs and high surface hardness can be expressed. Furthermore, from the viewpoint of reducing curing shrinkage, an organic / inorganic hybrid curable resin composition containing ultraviolet-reactive colloidal silica as an inorganic component having a reactive functional group can be mentioned as a more preferable example.

  Examples of means for imparting particularly excellent surface hardness include a method of adjusting the concentration of the inorganic component and / or the inorganic component having a reactive functional group contained in the hard coat layer (C). A preferable concentration range of the inorganic component and / or the inorganic component having a reactive functional group contained in the hard coat layer (C) is 10% by mass or more and 65% by mass or less. The lower limit of the preferred concentration is preferably 10% by mass or more, more preferably 20% by mass or more, and particularly preferably 40% by mass or more. A concentration of 10% by mass or more is preferable because an effect of imparting excellent surface hardness to the hard coat layer (C) can be obtained. On the other hand, the upper limit value of the preferred concentration is preferably 65% by mass or less, more preferably 60% by mass or less, and particularly preferably 55% by mass or less. If the concentration is 65% by mass or less, the hard coat layer (C) can be filled with an inorganic component and / or an inorganic component having a reactive functional group most closely, and an excellent surface hardness can be obtained. It is preferable because it can be applied to the target.

As a method for forming the hard coat layer (C), for example, by coating the surface of the resin layer as a paint obtained by dissolving or dispersing the curable resin composition in an organic solvent, a cured film is obtained. Although there is a method of forming and laminating on the surface of the resin layer, it is not limited to this method.
A known method is used as a method of laminating with the resin layer. For example, laminating method using cover film, dip coating method, natural coating method, reverse coating method, comma coater method, roll coating method, spin coating method, wire bar method, extrusion method, curtain coating method, spray coating method, The gravure coat method etc. are mentioned. In addition, for example, a method of laminating the hard coat layer (C) on the resin layer using a transfer sheet in which the hard coat layer (C) is formed on the release layer may be employed.
In addition, various surface treatments such as corona treatment, plasma treatment and primer treatment can be performed on the surface of the resin layer for the purpose of improving the adhesion between the hard coat layer (C) and the resin layer.

The curable resin composition for forming the hard coat layer (C) is preferably made of an ultraviolet curable resin from the viewpoint of molding time and productivity, that is, one that is cured by irradiation with ultraviolet rays. Here, as a light source that emits ultraviolet rays, an electrodeless high-pressure mercury lamp, an electroded high-pressure mercury lamp, an electrodeless metal halide lamp, an electroded metal halide lamp, a xenon lamp, an ultra-high pressure mercury lamp, a mercury xenon lamp, or the like can be used. Among these, an electrodeless high-pressure mercury lamp is preferable because it is easy to obtain ultraviolet rays with high illuminance and is advantageous for curing an ultraviolet curable resin.
Further, in the ultraviolet curable resin, the added photopolymerization initiator absorbs ultraviolet rays and is excited and activated to cause a polymerization reaction, and a curing reaction of the ultraviolet curable resin occurs. Therefore, it is preferable to select a light source according to the photopolymerization initiator added to the ultraviolet curable resin, that is, according to the excitation wavelength of the photopolymerization initiator, which is advantageous for curing the ultraviolet curable resin.

(Photopolymerization initiator)
When the curable resin composition is made of an ultraviolet curable resin and is cured by irradiation with ultraviolet rays, a photopolymerization initiator is used as a curing agent. Examples of the photopolymerization initiator include benzyl, benzophenone and derivatives thereof, thioxanthones, benzyldimethyl ketals, α-hydroxyalkylphenones, α-hydroxyacetophenones, hydroxyketones, aminoalkylphenones, acylphosphine oxides. Etc. Among these, α-hydroxyalkylphenones are preferable because they hardly cause yellowing during curing and a transparent cured product is obtained. In addition, aminoalkylphenones are preferable because they have very high reactivity and a cured product having excellent hardness can be obtained. The said photoinitiator can be used individually by 1 type or in combination of 2 or more types. In addition, it is preferable to add 0.1-5 mass parts of addition amount of a photoinitiator with respect to 100 mass parts of curable resin.

  Commercially available photopolymerization initiators can be used. Specific examples include “IRGACURE651”, “IRGACURE184”, “IRGACURE500”, “IRGACURE1000”, “IRGACURE2959”, “DAROCUR1173”, “IRGACURE127”, “IRGACURE907”. ”,“ IRGACURE 369 ”,“ IRGACURE 379 ”,“ IRGACURE 1700 ”,“ IRGACURE 1800 ”,“ IRGACURE 819 ”,“ IRGACURE 784 ”[The above IRGACURE (IRGACURE) series and DAROCUR (Darocur) series are BASF Japan products) Name], “KAYACUREITX”, “KAYACUREDETX-S”, “KAYAC REBP-100 "," KAYACUREBMS "," KAYACURE2-EAQ "[more KAYACURE (Kayacure) series, manufactured by Nippon Kayaku Co., Ltd. under the trade name], and others. Among these, examples of the above-mentioned α-hydroxyalkylphenones include “IRGACURE184”, while examples of the aminoalkylphenones include “IRGACURE907”, “IRGACURE369”, “IRGACURE379”. Can be mentioned.

(Surface conditioning component)
The curable resin composition forming the hard coat layer (C) can contain a leveling agent as a surface conditioning component. Examples of the leveling agent include silicone leveling agents and acrylic leveling agents. In particular, those having a reactive functional group at the terminal are preferable, and those having a reactive functional group having two or more functionalities are more preferable. preferable.
Specifically, polyether-modified polydimethylsiloxane having an acrylic group having a double bond at both ends (for example, trade names “BYK-UV 3500” and “BYK-UV 3530” manufactured by Big Chemie Japan Co., Ltd.)) And polyester-modified polydimethylsiloxane having an acrylic group having a total of four double bonds at the end (trade name “BYK-UV 3570” manufactured by Big Chemie Japan Co., Ltd.). Among these, polyester-modified polydimethylsiloxane having an acrylic group that has a stable haze value and contributes to improvement of scratch resistance is particularly preferable.

(Other ingredients)
In addition to the curable resin component, the curable resin composition for forming the hard coat layer (C) includes, for example, a lubricant such as a silicon compound, a fluorine compound, or a mixed compound thereof, an antioxidant, and an ultraviolet absorber. Various additives such as an agent, an antistatic agent, a flame retardant such as a silicone compound, a filler, glass fiber, and an impact modifier can be contained within a range that does not impair the effects of the present invention.

  When the curable resin composition is made of an ultraviolet curable resin and is cured by irradiating with ultraviolet rays, the resin composition has a high degree of transparency with respect to the ultraviolet rays. Because of the oxygen disorder), curing may be delayed on the surface of the resin composition. For this oxygen disorder, it is preferable to irradiate the resin composition with a nitrogen gas atmosphere by supplying nitrogen gas and then irradiate with ultraviolet rays, since the curing of the surface can proceed rapidly together with the inside of the resin composition. .

  The thickness of the hard coat layer (C) is not particularly limited, but is preferably in the range of 1 to 30 μm, more preferably in the range of 3 to 25 μm, and in the range of 5 to 20 μm. More preferably, it is particularly preferably in the range of 7 to 15 μm. Here, it is preferable if the thickness of the hard coat layer (C) is in the above range because scratch resistance can be imparted and cracks due to stress are unlikely to occur. Moreover, when it has a hard-coat layer (C) on both surfaces, the thickness of each hard-coat layer may be the same or different, but both are the range of 7-15 micrometers, and the surface of the resin layer (A) The thickness of the hard coat layer is preferably equal to or greater than the thickness of the hard coat layer on the surface of the polycarbonate resin layer (B).

  One or more of antireflection treatment, antifouling treatment, antistatic treatment, weather resistance treatment and antiglare treatment is applied to one or both sides of the laminate having the hard coat layer (C) according to the present invention. be able to. Each processing method is not particularly limited, and a known method can be used. For example, a method of applying a reflection reducing coating, a method of depositing a dielectric thin film, a method of applying an antistatic coating, and the like can be exemplified.

(Abrasion resistance)
The steel wool test can be evaluated as one index for the scratch resistance of the surface of the hard coat layer (C) applied to the outer surface side. Here, it is preferable that the number of reciprocations until scratching is 20 times or more when rubbing with a load of 1000 gf using # 0000 steel wool. When the number of reciprocations until the surface is scratched when rubbed with the steel wool is 20 times or more, it is possible to provide a scratch-resistant laminate having excellent scratch resistance. From this point of view, the number of reciprocations until the surface is scratched is preferably 20 times or more, more preferably 300 times or more, and particularly preferably 500 times or more.

(Assumed use)
As described above, the laminate of the present invention is excellent in economy by using a general-purpose material as a main raw material, and has transparency, impact resistance, surface hardness, high temperature and high used for a substrate material and a protective material. Since it is a laminate excellent in shape stability in a humid environment, it can be applied to various applications and is not particularly limited.
In particular, the laminate can be used as various substrate materials and protective materials. Specifically, portable display devices (mobile phone terminals, smartphones, portable electronic playground equipment, personal digital assistants, tablet devices, mobile PCs, etc.) and stationary display devices (LCD TVs, LCD monitors, desktop PCs, car navigation systems, It can be suitably used for automobile instruments and the like.
Furthermore, the laminate having other layers such as the laminate of the present invention and the hard coat layer (C) may be given a shape by various processing methods. Specific examples include a method of heating and pressurizing using a mold, a pressure forming method, a vacuum forming method, a roll forming method, and the like. By applying the shape, application to an image display device having a curved surface and various flexible devices can be expected.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. Various measured values and evaluations displayed in this specification were performed as follows.

(1) Glass transition temperature (Tg)
Using a differential scanning calorimeter manufactured by PerkinElmer, Inc., under the trade name “Pyris1 DSC”, according to JIS K7121, about 10 mg of the sample was heated from −40 ° C. to 200 ° C. at a heating rate of 10 ° C./min. After holding at 200 ° C. for 1 minute, the temperature was lowered to −40 ° C. at a cooling rate of 10 ° C./min, and again from the thermogram measured when the temperature was raised to 200 ° C. at a heating rate of 10 ° C./min, the glass transition temperature (Tg ) (° C). In addition, the value of Tg was rounded off to the first decimal place.

(2) Water absorption rate
After molding the composition constituting each layer to a thickness of 1 mm, a 100 mm square test piece (n = 3) was cut out, first left in an environment of temperature 23 ° C. and humidity 50% RH for 24 hours, and the weight was measured. the value was defined as _{W 1.} Next, each test piece was allowed to stand for 120 hours in an environment of temperature 85 ° C. and humidity 85% RH, the weight after water absorption was measured, and the value was defined as W ₂ . And the water absorption (%) was calculated | required with the following formula | equation.
(Water absorption) = (W ₂ −W ₁ ) / W ₁ × 100

(3) Pencil hardness
The pencil hardness was measured with a load of 750 g according to JIS K5600-5-4 on the surface to be measured. The pencil hardness on the surface of the resin layer (A) was H or higher, and the pencil hardness on the surface of the polycarbonate resin layer (B) having the hard coat layer (C) was F or higher (O).

(3) Total light transmittance A 50 mm square test piece was cut out from the obtained laminate, the total light transmittance was measured according to JIS K7361-1, and the value was evaluated according to the following criteria.
(◎) Total light transmittance is 89% or more (○) Total light transmittance is 85% or more and less than 89% (×) Total light transmittance is less than 85%

(4) Warpage evaluation
A 100 mm square test piece (n = 3) was cut out from the obtained laminate, and first left in a temperature 23 ° C., humidity 50% RH environment for 24 hours. Next, each test piece was allowed to stand for 120 hours in a temperature of 85 ° C. and a humidity of 85% RH, and then left for 24 hours in a temperature of 23 ° C. and a humidity of 50% RH. Then, the test piece was allowed to stand on a surface plate. The height from the surface plate at the four corners was measured as the amount of warpage, and the average absolute value was evaluated according to the following criteria. However, the symbol “Δ” is also above the practical level.
(◎) Warpage amount is 0.5 mm or less (◯) Warpage amount is more than 0.5 mm, 1.0 mm or less (Δ) Warpage amount is more than 1.0 mm, and 1.5 mm or less (×) Warpage amount is 1. Over 5mm

(5) Impact resistance
A test piece having a width of 50 mm and a length of 120 mm was cut out from the obtained laminate, and both ends of the test piece were held 10 mm each using a metal holder with the resin layer (A) facing upward. Next, a metal ball having a weight of 133 g from a distance of 5 cm from the test piece is dropped on the center of the test piece to measure whether the test piece is broken or not. If no breakage occurs, the distance is increased by 5 cm and the same test is performed. The distance until destruction occurred was measured and evaluated according to the following criteria. However, the symbol “Δ” is also above the practical level.
(○) Distance until destruction occurs 30 cm or more (△) Distance until destruction occurs 5 cm or more, less than 30 cm (×) Distance until destruction occurs less than 5 cm

(6) Adhesiveness Regarding the adhesiveness between the hard coat layer (C) and the laminate surface, a cross-cut test was conducted in accordance with JIS K5600-5-6, and the hard coat layer was not peeled off. It was set as a pass (◯).

(7) Evaluation of scratch resistance The scratch resistance of the hard coat layer (C) is measured with the following apparatus and conditions. Those less than the number of times were determined to be rejected (x).
・ Equipment: Friction fastness tester Gakushin type (manufactured by Daiei Scientific Instruments)
・ Steel wool count: # 0000
・ Test load: 1000gf
・ Test speed: 30 reciprocations / minute ・ Test stroke: 120 mm

The main raw materials used in Examples and Comparative Examples are described below.
(Acrylic resin (a1))
(A1-1); acrylic resin (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Acrypet VH001, density: 1.19 g / cm ³ , methyl methacrylate / methyl acrylate = 99/1% by mass, stereoregularity (Triad fraction): mm (9.2 mol%), mr (41.8 mol%), rr (49.0 mol%), Tg: 111 ° C., MFR (temperature: 230 ° C., load: 37.3 N) ): 2.0 g / 10 min)

(Copolymer (a2))
(A2-1); Copolymer (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name: Regisphi R-100, density: 1.14 g / cm ³ , styrene / methyl methacrylate / maleic anhydride = 75/15 / 10% by mass, Tg: 127 ° C., MFR (temperature: 230 ° C., load: 37.3 N): 4.2 g / 10 min)

(Polycarbonate resin (b1))

(B1-1); polycarbonate resin (manufactured by Sumika Stylon Polycarbonate Co., Ltd., trade name: Caliber 301-10, density: 1.20 g / cm ³ , Tg: 149 ° C., MFR (temperature: 300 ° C., load: 11.8N): 10.0 g / 10 min

(Copolymer (b2))
(B2-1): Copolymer (manufactured by Mitsubishi Rayon Co., Ltd., trade name: methabrene H-880, phenyl methacrylate / methyl methacrylate = 34/66 mass%, weight average molecular weight: 14,000)

<Examples 1-5>
The resin composition mixed in the ratio shown in Table 1 is supplied to separate extruders having a vent function and a filter function, melt-kneaded at a resin temperature of 240 to 265 ° C., and (A) layer / (M ) Layer / (B) layer was coextruded with a 260 ° C. T-die and cast-cooled with a mirror roll at 95 ° C. to obtain a laminate having the thickness structure shown in Table 1. . The resulting laminate had good appearance and excellent flatness. The results of evaluation using the laminate are shown in Table 1.

<Comparative Example 1>
As shown in Table 1, a laminate having excellent appearance and flatness was obtained in the same manner as in Example 1 except that the (M) layer was not provided. The results of evaluation using the laminate are shown in Table 1.

<Comparative Example 2>
As shown in Table 1, a laminate having excellent appearance and flatness was obtained in the same manner as in Comparative Example 1 except that the thickness of the (A) layer was changed. The results of evaluation using the laminate are shown in Table 1.

<Comparative Example 3>
As shown in Table 1, a laminate having excellent appearance and flatness was obtained in the same manner as in Comparative Example 1 except that the configuration was changed to be (A) layer / (B) layer / (A) layer. . The results of evaluation using the laminate are shown in Table 1.

<Comparative example 4>
As shown in Table 1, a laminate having excellent appearance and flatness was obtained in the same manner as in Example 2 except that the layer (A) was not provided. The results of evaluation using the laminate are shown in Table 1.

From Table 1, it can confirm that the resin laminated body prescribed | regulated by this invention is excellent in transparency, surface hardness, shape stability in high temperature, high humidity environment, and impact resistance (Examples 1-5).
On the other hand, it can confirm that the laminated body outside the range prescribed | regulated by this invention has one or more malfunctions (comparative examples 1-4). When the intermediate layer (M) is not provided, the surface hardness or the shape stability under high temperature and high humidity environment is insufficient (Comparative Examples 1 and 2), and the structure having the resin layer (A) on both sides is shock resistant. The properties are insufficient (Comparative Example 3). Moreover, when it does not have a resin layer (A), pencil hardness becomes inadequate (comparative example 4).

<Examples 6 to 8>
As shown in Table 2, an organic / inorganic hybrid ultraviolet curable resin composition (manufactured by MOMENTIVE, trade name: SilFORT UVHC7800G, inorganic silica having a reactive functional group) on the surface of the laminate obtained in Examples 1 and 2 (Content: 30 to 40% by mass) was applied using a metal bar coater, dried at 90 ° C. for 1 minute, and then exposed to an exposure amount of 500 mJ / cm ² using an ultraviolet irradiation device, and a hard coat layer ( A laminate having C) was obtained. Table 2 shows the results of evaluating the hard coat layer of the laminate. In addition, when apply | coating to both surfaces, the hard-coat layer was formed for each surface, and ultraviolet irradiation was similarly performed to each surface.

  From Table 2, it can be confirmed that the surface hardness can be improved and scratch resistance can be imparted by applying the hard coat layer (C) to the surface of the laminate of the present invention. Moreover, it can confirm that it is excellent also in the adhesiveness of the surface of the laminated body of this invention, and a hard-coat layer (C) (Examples 6-8). The hard coat layer (C) applied to the outer surface side of the laminate of the present invention shares the function of developing excellent surface hardness, while the hard coat layer (C) applied to the inner surface side is used in the process. The function can be shared as an anti-scratch layer for preventing frictional scratches from entering the laminate during transportation or processing.

Claims (9)

A laminate having at least one intermediate layer (M) between a resin layer (B) containing a polycarbonate resin (b1) and a resin layer (A) containing an acrylic resin (a1), and A laminate having the following properties (i) and (ii):
(I) When the water absorption rate of the resin layer (A) after being left in a high temperature and high humidity environment of 85 ° C. and 85% RH for 120 hours is W _A , and the water absorption rate of the intermediate layer is W _M , W _M <W _A.
When the pencil hardness _{H B} of (ii) the resin layer was measured according to JIS K5600-5-4 (B), the pencil hardness of the intermediate layer was changed to _{H M,} is _H B <H _M.   The intermediate layer (M) is a copolymer having the acrylic resin (a1), an aromatic vinyl monomer unit, a (meth) acrylic acid ester monomer unit, and an unsaturated dicarboxylic anhydride monomer unit. The laminate according to claim 1, comprising (a2), wherein the mixing mass ratio is (a1) / (a2) = 80 to 20/20 to 80.   The intermediate layer (M) is a copolymer (b2) comprising the polycarbonate resin (b1), aromatic (meth) acrylate monomer units 5 to 80% by mass and methyl methacrylate monomer units 95 to 20% by mass. ), And the mixing mass ratio thereof is (b1) / (b2) = 99 to 65/1 to 35. The laminate according to claim 1, wherein   When the total thickness of the resin layer (A), the intermediate layer (M), and the resin layer (B) is (T), the resin layer (A) and the intermediate layer (M) are added together 2 4. The laminate according to claim 1, wherein the ratio [(A) + (M)] / (T) of the total thickness of the layers is in a range of 0.01 to 0.30. body.   The laminate according to any one of claims 1 to 4, wherein the thickness of the resin layer (A) is in the range of 0.01 to 0.1 mm.   The laminate according to any one of claims 1 to 5, wherein a hard coat layer (C) is laminated on at least one surface of the laminate.   The board | substrate material using the laminated body of any one of Claims 1-6.   The protective material using the laminated body of any one of Claims 1-6.   The image display apparatus containing the laminated body of any one of Claims 1-6.