Laminate and molded article comprising the same

Abstract

To provide a laminate including a resin layer comprising a thermoplastic acrylic resin and a resin layer comprising a polycarbonate resin, exhibiting good transparency, and capable of reducing occurrence of cracking, fracture, and whitening of the laminate in secondary molding over a broad temperature range, and a molded article including the same.SOLUTION: A laminate comprises a resin layer (A) and a resin layer (B), wherein the resin layer (A) is composed of a resin composition (A) containing a thermoplastic acrylic resin (a) comprising 50 wt.% or more of methyl methacrylate units, the resin layer (B) is composed of a resin composition (B) containing a polycarbonate resin (b), the thickness of the laminate is 350 μm or less, the haze in the thickness direction of the laminate is less than 2%, the tensile breaking elongation at 130°C to 160°C is 200% or more when the elongation before stretching of the laminate is set to 0%, and the haze of the region uniformly stretched at an elongation of 150% at 130°C to 160°C is less than 3%.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a laminate including a resin layer containing a thermoplastic acrylic resin and a resin layer containing a polycarbonate resin, and a molded article including the same.

Background Art

[0002] Acrylic resins represented by polymethyl methacrylate are used and developed for various applications by taking advantage of excellent properties such as transparency, hardness, and weather resistance. As applications of acrylic resins, for example, decorative and protective applications in which a film is laminated on interior and exterior automotive parts, decorative and protective applications of exterior members of electronic devices such as mobile electronic devices, personal computers, and home appliances, protection of the display surface part, and applications for weather resistance protection of the surfaces of building materials and the like can be mentioned. In such applications, the acrylic resin is processed into a film shape and laminated on the surface of the molded article by various methods.

[0003] Since acrylic resins are relatively brittle materials, as one method for enabling handling as a film, core-shell type rubber particles, an elastomer component, etc. are added to the acrylic resin to impart flexibility in the film shape and secondary moldability during heat processing while maintaining transparency. Such a method has become common.

[0004] As another method for using an acrylic resin material as a transparent decorative / protective film, there is a method of laminating a resin layer made of a polycarbonate resin having excellent toughness on a resin layer made of an acrylic resin (for example, Patent Documents 1 and 2). As uses of a film material having a multilayer structure composed of an acrylic resin layer and a polycarbonate resin layer (hereinafter, also referred to as an acrylic / PC multilayer film), in addition to use as a protective material for a flat surface of a display device or a base material of the protective material, for example, by using any of molding methods such as vacuum forming, film insert molding, in-mold injection molding, and three-dimensional lamination molding, by laminating on a surface having a curved or three-dimensional shape portion of a molded body such as a transparent cover of a display device, the entire molded body is decorated and / or protected, the display display surface is protected, and it is also used as a molding film or a base material of a molding film for imparting characteristics such as optical functions (for example, Patent Documents 3 and 4).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0006] When applying a film material to a lamination application on a surface having a curved shape or a three-dimensional shape portion, it may be necessary to subject the film material to a secondary forming process of shaping it into a shape along the surface of the molded body as needed. However, since conventional acrylic / PC multilayer films laminate two resin materials with different properties, for example, during stretching associated with secondary forming, the interface between the acrylic resin and the polycarbonate resin peels off, and the interface or the inside of the polycarbonate resin layer becomes cloudy or whitened, and there are problems such as the film cracking and / or breaking. For this reason, conventional acrylic / PC multilayer films do not necessarily have sufficient performance from the viewpoints of secondary formability, stretchability, or followability to the surface shape required for lamination on a surface having a curved surface or a three-dimensional shape.

[0007] The present invention has been made in view of the above problems, and includes a resin layer containing a thermoplastic acrylic resin and a resin layer containing a polycarbonate resin, has good transparency, improved secondary formability in a wide temperature range, and can suppress cracking, breaking, and whitening of the laminate during secondary forming. The present invention provides a laminate and a molded body including the same.

Means for Solving the Problems

[0008] One or more embodiments of the present invention are laminates including a resin layer (A) and a resin layer (B), wherein the resin layer (A) is composed of a resin composition (A) containing a thermoplastic acrylic resin (a) containing 50% by weight or more of methyl methacrylate units, the resin layer (B) is composed of a resin composition (B) containing a polycarbonate resin (b), the thickness of the laminate is 350 μm or less, the haze in the thickness direction of the laminate is less than 2%, when the elongation before stretching of the laminate is set to 0%, the tensile fracture elongation at 130°C to 160°C is 200% or more, and the haze of the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C is less than 3%.

[0009] One or more embodiments of the present invention relate to a laminate and a molded body substrate, wherein the laminate is laminated on the surface of the molded body substrate.

Advantages of the Invention

[0010] According to the present invention, there is provided a laminate including a resin layer containing a thermoplastic acrylic resin and a resin layer containing a polycarbonate resin, which has improved secondary moldability in a wide temperature range and can suppress cracking, breakage, and whitening of the laminate during secondary molding, and a molded body including the same.

Embodiments for Carrying Out the Invention

[0011] The inventors of the present invention have intensively studied to solve the above problems. As a result, in a laminate including a resin layer made of a resin composition containing a thermoplastic acrylic resin and a resin layer made of a resin composition containing a polycarbonate resin, when the thickness of the laminate is set to 350 μm or less, which is suitable as a molding film used for decoration and protection of the surface of the molded body, the haze in the thickness direction is less than 2%, the tensile elongation at break during stretching at 130 to 160 ° C is 200% or more, and the haze of the stretched portion uniformly stretched at an elongation of 150% at 130 to 160 ° C is less than 3%, a laminate having high transparency and improved secondary moldability in a wide temperature range can be obtained, and it has been found that cracking, breakage, and whitening of the laminate during secondary molding can be suppressed.

[0012] In this specification, when a numerical range is indicated by "~", the numerical range includes both end values (upper limit and lower limit). For example, the numerical range of "X~Y" is a range including both end values of X and Y, and is the same range as "X or more and Y or less". Also, any number within the range and any range included within the range are specifically disclosed. Further, in this specification, when a plurality of numerical ranges are described, it is assumed to include numerical ranges obtained by appropriately combining the upper and lower limits of different numerical ranges.

[0013] (Resin Layer A) The resin layer (A) is composed of a resin composition (A) containing a thermoplastic acrylic resin (a) containing 50% by weight or more of methyl methacrylate units. The resin composition (A) preferably contains 50% by weight or more of the thermoplastic acrylic resin (a), more preferably 80% by weight or more. The resin composition (A) may contain no resin components other than the thermoplastic acrylic resin.

[0014] As the thermoplastic acrylic resin (a), a known thermoplastic acrylic resin containing 50% by weight or more of methyl methacrylate units can be appropriately used. For example, from the viewpoints of hardness and moldability, when the total amount of the constituent units of the thermoplastic acrylic resin (a) is 100% by weight, a thermoplastic acrylic resin (a) containing 50 to 100% by weight of methyl methacrylate units and 0 to 50% by weight of other constituent units is preferable, and a thermoplastic acrylic resin (a) containing 80 to 100% by weight of methyl methacrylate units and 0 to 20% by weight of other constituent units is more preferable. Note that the total amount of the methyl methacrylate units and other constituent units in the thermoplastic acrylic resin (a) is 100% by weight.

[0015] Examples of the other constituent units include constituent units derived from acrylic acid, acrylic acid derivatives, methacrylic acid, methacrylic acid derivatives, aromatic vinyl derivatives, vinyl cyanide derivatives, etc. The other constituent units may include a glutarimide structure, a lactone ring structure, an N-substituted maleimide structure, an unsubstituted maleimide structure, etc., which will be described later. The other constituent units contained in the thermoplastic acrylic resin (a) may be of one kind or a combination of two or more kinds.

[0016] Examples of the acrylic acid derivatives include acrylic acid esters such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, 2-phenoxyethyl acrylate, benzyl acrylate, and glycidyl acrylate, but are not limited thereto.

[0017] Examples of the methacrylic acid derivative include, but are not limited to, methacrylic acid esters such as ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, phenyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, 2-phenoxyethyl methacrylate, and isobornyl methacrylate, and reactive ultraviolet absorbers such as 2-(2'-hydroxy-5'-(meth)acryloyloxyethylphenyl)-2H-benzotriazoles.

[0018] Examples of the aromatic vinyl derivative include, but are not limited to, styrene, vinyltoluene, and α-methylstyrene.

[0019] Examples of the vinyl cyanide derivative include, but are not limited to, acrylonitrile and methacrylonitrile.

[0020] The thermoplastic acrylic resin (a) is not particularly limited. For example, in order to improve heat resistance, rigidity, surface hardness, etc., at the time of polymerization of the thermoplastic acrylic resin, the stereoregularity of the main chain is controlled, and syndiotactic PMMA (hereinafter also referred to as PMMA) having a higher ratio of a syndiotactic structure with higher heat resistance than that in the case of general radical polymerization of polymethyl methacrylate may be used. Examples of such syndiotactic PMMA include those described in JP-A No. 2017-048344, WO 2014 / 185508, WO 2014 / 185509, and WO 2023 / 238885.

[0021] As the thermoplastic acrylic resin (a), a thermoplastic acrylic resin having a structural unit with a specific structure introduced by copolymerization, functional group modification, modification, etc. may be used in order to improve heat resistance, rigidity, surface hardness, etc. Examples of such a specific structure include a glutarimide structure as shown in JP-A-62-89705, JP-A-02-178310, and WO 2005 / 54311, a lactone ring structure as shown in JP-A-2004-168882 and JP-A-2006-171464, a glutaric anhydride structure obtained by thermally condensing a (meth)acrylic acid unit as shown in JP-A-2004-307834, a maleic anhydride structure as shown in JP-A-5-119217, and an N-substituted maleimide structure and an unsubstituted maleimide structure as shown in WO 2009 / 84541. For example, when these structures are introduced into the thermoplastic acrylic resin, the molecular chain becomes rigid. As a result, effects such as improvement in heat resistance, improvement in surface hardness, reduction in heat shrinkage, and improvement in chemical resistance can be expected. In this specification, (meth)acrylic acid is a general term for acrylic acid and methacrylic acid.

[0022] The production method of the thermoplastic acrylic resin (a) is not particularly limited, and for example, known polymerization methods such as suspension polymerization, bulk polymerization, solution polymerization, and emulsion polymerization can be applied. Also, any of known radical polymerization, living radical polymerization, anionic polymerization, and cationic polymerization can be applied.

[0023] The resin composition (A) may contain a rubber component in addition to the thermoplastic acrylic resin (a). The resin composition (A) is not particularly limited. For example, it may contain 0 to 50% by weight of the rubber component, or it may contain 0 to 20% by weight. The rubber component may be graft copolymer particles, preferably graft copolymer particles having an average particle diameter of 20 to 250 nm. In this case, it is preferable that the resin composition (A) has the graft copolymer particles dispersed in a hard matrix resin layer containing the thermoplastic acrylic resin (a). Further, the resin composition (A) may contain a plurality of graft copolymer particles having different average particle diameters and structures and dispersed in the thermoplastic acrylic resin (a). Examples of such a resin composition containing a thermoplastic acrylic resin and a rubber component (for example, graft copolymer particles having an average particle diameter of 20 to 250 nm) include, but are not limited to, those described in, for example, Japanese Patent Publication No. 55-27576, Patent No. 3960631, Patent No. 4291994, Patent No. 7219753, and Patent No. 7245082, etc.

[0024] The resin composition (A) may contain, as necessary and within a range not impairing the object of the present invention, a thermoplastic acrylic resin (a) and other thermoplastic resins that are at least partially compatible therewith. Examples of the other thermoplastic resins include styrenic resins, polycarbonate resins, amorphous saturated polyester resins, olefin-methacrylic acid derivative resins, olefin-acrylic acid derivative resins, polyimide resins, polylactic acid resins, and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) resins. Examples of the styrenic resins include styrene-acrylonitrile resins, styrene-(meth)acrylic acid resins, styrene-maleic anhydride resins, styrene-N-substituted or unsubstituted maleimide resins, styrene-acrylonitrile-butadiene resins, and styrene-acrylonitrile-acrylic ester resins. Among them, one or more thermoplastic resins selected from the group consisting of styrenic resins, polycarbonate resins, and polyimide resins are preferable because they are excellent in compatibility with the thermoplastic acrylic resin (a) and may improve the flexural crack resistance, solvent resistance, chemical resistance, and low hygroscopicity of the resin layer (A). The resin composition (A) is not particularly limited, but for example, it may contain 0 to 50% by weight, or 0 to 20% by weight, of the other thermoplastic resins.

[0025] The resin composition (A) may also contain, as necessary and within a range not impairing the object of the present invention, conventionally known additives. Examples of such additives include antioxidants, ultraviolet absorbers, light stabilizers, light diffusing agents, matting agents, lubricants, coloring agents such as pigments and dyes, fibrous fillers, antiblocking agents composed of organic particles and / or inorganic particles, infrared reflectors composed of metals and / or metal oxides, plasticizers, and antistatic agents, but are not limited thereto. These additives can be used in any amount according to the type of additive, as long as they do not inhibit the object of the present invention or enhance the effect of one embodiment of the present invention. The resin composition (A) is not particularly limited, but for example, it may contain 0 to 30 parts by weight, or 0 to 20 parts by weight, of the additives based on 100 parts by weight of the resin components (the total of the thermoplastic acrylic resin (a), the rubber component, and the other thermoplastic resins).

[0026] The glass transition temperature of the resin composition (A) is not particularly limited. For example, from the viewpoint of the balance between the heat resistance and secondary moldability of the laminate, it may be 85 to 140°C, may be 90 to 135°C, or may be 95 to 130°C. In this specification, the glass transition temperature can be determined using a known method such as a differential scanning calorimeter (DSC).

[0027] (Resin layer B) The resin layer (B) is composed of a resin composition (B) containing a polycarbonate resin (b). The resin composition (B) preferably contains 50 to 99% by weight of the polycarbonate resin (b). Further, the resin composition (B) more preferably contains 50 to 99% by weight of the polycarbonate resin (b) and has a glass transition temperature of 140°C or lower, still more preferably a glass transition temperature of 135°C or lower, and even more preferably a glass transition temperature of 130°C or lower. When the glass transition temperature of the resin composition (B) is within the above-described range, the tensile elongation at break of the laminate at 130°C to 160°C is 200% or more, and the haze of the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C is likely to be less than 3%, and it is easy to suppress the occurrence of breakage, cracking, and whitening during stretching accompanying the secondary molding of the laminate. The lower limit of the glass transition temperature of the resin composition (B) is not particularly limited, but when the glass transition temperature of the resin composition (A) is TgA, it is preferably [TgA - 10°C] or higher, [TgA - 8°C] or higher, or [TgA - 6°C] or higher from the viewpoint of not excessively reducing the heat resistance.

[0028] The polycarbonate resin (b) preferably contains 80% by weight or more of a structural unit composed of a carbonate ester of a dihydric phenol compound.

[0029] Examples of the diphenol compound include, but are not limited to, bis(4-hydroxyphenyl)methane (also referred to as bisphenol F), 2,2-bis(4-hydroxyphenyl)propane (also referred to as bisphenol A), 1,1-bis(4-hydroxyphenyl)cyclohexane, 9,9-bis(4-hydroxyphenyl)fluorene, hydroquinone, resorcinol, and 4,4'-dihydroxydiphenyl, or aromatic nucleus-substituted products thereof by an alkyl group, aryl group, halogen group, alkoxy group, etc.

[0030] As the polycarbonate resin (b), bisphenol A type polycarbonate in which the diphenol compound is bisphenol A can be preferably used. A polycarbonate polymerized using other diphenol compounds other than bisphenol A may also be used, or a polycarbonate polymerized by using bisphenol A and other diphenol compounds in combination may be used.

[0031] The polycarbonate resin (b) may be a copolymer of a diphenol compound and an aliphatic diol and / or an alicyclic diol. Examples of the alicyclic diol include, but are not limited to, 2,2-bis(4-hydroxycyclohexyl)propane, isosorbide, cyclohexanediol, and cyclohexanedimethanol.

[0032] The polycarbonate resin (b) can be produced by appropriately using a known polymerization method without limitation. Examples of the polymerization method of the polycarbonate resin (b) include, but are not limited to, an interfacial polycondensation method using a diphenol compound and a carbonylating agent, a melt transesterification method, a transesterification method between carbonate prepolymers, and a ring-opening polymerization method of a cyclic carbonate compound.

[0033] The polycarbonate resin (b) is not particularly limited. For example, the weight-average molecular weight is preferably 14,000 to 35,000, more preferably 15,000 to 32,000, and even more preferably 18,000 to 31,000. When the weight-average molecular weight of the polycarbonate resin (b) is 14,000 or more, the toughness of the polycarbonate resin is high and the laminate is less likely to crack. When the weight-average molecular weight of the polycarbonate resin (b) is 35,000 or less, the melt viscosity does not become too high, the melt molding of the laminate becomes easy, the residual stress in the laminate is low, and the occurrence of cracks and warpage is easily suppressed. The weight-average molecular weight of the polycarbonate resin (b) can be measured, for example, by gel permeation chromatography (GPC).

[0034] In addition to the polycarbonate resin (b), the resin composition (B) may further contain a transparent thermoplastic resin (b2). The resin composition (B) may contain 1 to 50% by weight of the transparent thermoplastic resin (b2). The transparent thermoplastic resin (b2) has compatibility with the polycarbonate resin (b) and has the effect of lowering the glass transition temperature of the polycarbonate resin (b) when mixed. Preferably, it has the effect of lowering the glass transition temperature of the polycarbonate resin (b) while maintaining the transparency, toughness, affinity and adhesion with the thermoplastic acrylic resin (a) or the resin composition (A) of the polycarbonate resin (b). Such resins include polycarbonate resins having the above-mentioned dihydric phenols, etc. as structural units (however, excluding those used as the main component of the resin composition (B) as the polycarbonate resin (b)), those having a glass transition temperature lower than that of the polycarbonate resin (b), and one or more selected from the group consisting of amorphous polyester resins are preferred.

[0035] Examples of the amorphous polyester resin include polyester resins such as polyalkylene terephthalate, polyalkylene naphthalate, polyarylate, polyhydroxyalkylene carboxylate, polyalkylene succinate, polylactic acid, polyalkylene adipate, polycaprolactone, or modified polyesters obtained by partially introducing and / or completely substituting other components while using these as the basic skeleton, and those in which crystallinity is suppressed by some method or those having no crystallinity.

[0036] Preferred examples of the amorphous polyester resin include polyethylene terephthalate, polytrimethylene terephthalate, polytetraethylene terephthalate, polyethylene naphthalate, or those having a basic skeleton such as polyarylate obtained by polycondensing or addition-condensing the above-described dihydric phenol compound and a dicarboxylic acid derivative such as terephthalic acid and / or isophthalic acid. Further, for the purpose of suppressing the crystallinity of these polyester resins, two or more different polyester resins may be used in combination, or modification may be appropriately performed by partially introducing a diol component or a dicarboxylic acid component having a different structure into the polyester resin and / or completely substituting these components.

[0037] Examples of preferred modifications of the polyester resin include, for example, a structure in which some or all of the terephthalic acid units and / or ethylene glycol units, which are the constituent units of polyethylene terephthalate, are replaced with isophthalic acid units and / or 1,4-cyclohexanedimethanol units. Among these, a modified polyester in which the structure is replaced by copolymerization of one or more components selected from the group consisting of 1,4-cyclohexanedimethanol and isophthalic acid with respect to polyethylene terephthalate having ethylene glycol units and terephthalic acid units as constituent units is preferable in terms of excellent crystalinity suppression, transparency, and mechanical properties. Furthermore, a modified polyester in which the structure is replaced by copolymerization of 1,4-cyclohexanedimethanol with polyethylene terephthalate having ethylene glycol units and terephthalic acid units as constituent units is particularly preferable because it is excellent in maintaining transparency and toughness when mixed with a polycarbonate resin. More specifically, the transparent thermoplastic resin (b2) is a polyester resin containing ethylene glycol units and terephthalic acid units as constituent units, and is an amorphous polyester resin further containing one or more constituent units selected from the group consisting of cyclohexanedimethanol units and isophthalic acid units, and a polyester resin containing cyclohexanedimethanol units and terephthalic acid units as constituent units, and may further contain one or more constituent units selected from the group consisting of ethylene glycol units and isophthalic acid units, and is preferably 1 or more selected from the group consisting of amorphous polyester resins.

[0038] As the resin composition (B), a commercially available resin composition containing a polycarbonate resin may also be used. The glass transition temperature is preferably lower than that of bisphenol A polycarbonate resin, more preferably 140 °C or lower, still more preferably 135 °C or lower, and even more preferably 130 °C or lower. Examples of the resin composition having transparency include those having, as the main component (containing 50 to 99% by weight), bisphenol A polycarbonate resin as the polycarbonate resin (b) and containing an amorphous polyester resin as the transparent thermoplastic resin (b2), and having a glass transition temperature of 140 °C or lower. More preferably, the glass transition temperature is 135 °C or lower, and even more preferably 130 °C or lower. Examples of such commercially available products include "SP3002" and "SP3012" manufactured by Sumitomo Chemical Polycarbonate Co., Ltd.

[0039] The resin composition (B) may contain, as necessary, conventionally known additives as long as the object of the present invention is not impaired. Examples of such additives include the same ones as the conventionally known additives that can be used in the resin composition (A). The same additives as those in the resin composition (A) may be added, or different additives from those in the resin composition (A) may be used. The resin composition (B) is not particularly limited. For example, it may contain 0 to 10 parts by weight, or 0 to 5 parts by weight of additives based on 100 parts by weight of the total resin components (the total of the polycarbonate resin (b) and the transparent thermoplastic resin (b2)).

[0040] (Laminate) In one or more embodiments of the present invention, the laminate includes the above-described resin layer (A) and resin layer (B). In the laminate, the resin layer (A) and the resin layer (B) may be directly laminated, and within the range that does not inhibit the effects of the present invention, other functional layers laminated between the resin layer (A) and the resin layer (B) may be included as necessary. The other functional layers may be laminated on one or both sides of the resin layer (A) and / or the resin layer (B).

[0041] The other functional layers are not particularly limited, and conventionally known ones can be widely applied. For example, a printing layer, a decorative layer, an adhesive layer, an antistatic layer, a thermoplastic resin layer, and an optical functional layer can be mentioned. The decorative layer may include a coloring layer, a design layer, a surface uneven layer, an emboss layer, etc. The adhesive layer may include a primer layer, etc. The thermoplastic resin layer may include an antifouling layer, an antiglare layer, a fingerprint-resistant layer, a hard coat layer, a scratch-resistant layer, a gas barrier layer, and a gas absorption layer, etc. Examples of the optical functional layer include an antireflection layer (a low refractive index layer, a high refractive index layer, an ultraviolet ray shielding layer, an infrared ray shielding layer, etc.), a light diffusion layer, an antiglare layer, a matte layer, a retardation adjustment layer, a viewing angle adjustment layer, and a polarizing layer, etc. The laminate may be provided with two or more combinations of other functional layers. Also, one functional layer may have two or more functions. The other functional layer may be one or more selected from the group consisting of a hard coat layer, an antireflection layer, an antiglare layer, an antifouling layer, an antistatic layer, a conductive layer, an adhesive layer, a printing layer, and a decorative layer.

[0042] The thickness of the laminate is 350 μm or less, preferably 30 to 350 μm, more preferably 50 to 300 μm, and even more preferably 75 to 250 μm. When the thickness of the laminate is 350 μm or less, production and management as a film roll are easy, the time required for heating during secondary molding can be shortened, and uniform and smooth molding is easy, so the secondary moldability is improved and the cost can be reduced. When the thickness of the laminate is 30 μm or more, it is easy to produce the laminate, and breakage of the laminate is less likely to occur.

[0043] When the laminate includes other functional layers, the thickness of the other functional layers is not particularly limited as long as the intended functionality can be exhibited. For example, it may be 0.1 to 15 μm or 0.5 to 10 μm.

[0044] The thickness ratio of resin layer (A) to resin layer (B) (resin layer (A) / resin layer (B)) is preferably from 97 / 3 to 5 / 95, more preferably from 90 / 10 to 10 / 90, still more preferably from 20 / 80 to 80 / 20, and even more preferably from 30 / 70 to 80 / 20. When the thickness ratio of resin layer (A) is 5% or more, it is easy to exhibit physical properties such as weather resistance, surface hardness, and low retardation, which are characteristics of thermoplastic acrylic resins. When the thickness ratio of resin layer (B) is 3% or more, toughness, which is a characteristic of polycarbonate resins, is easily exhibited, and it becomes easy to impart crack resistance to the laminate.

[0045] The laminate has a haze in the thickness direction of less than 2.0%. Thereby, the transparency becomes good. The haze in the thickness direction of the laminate is preferably 1.5% or less, more preferably 1.0% or less, still more preferably 0.8% or less, even more preferably 0.6% or less, even more preferably 0.4% or less, and particularly preferably 0.3% or less. However, depending on the use of the laminate, when a matting agent, an antiglare agent, a colorant, a filler, etc. are blended in resin layer (A) and / or resin layer (B), or when the surface or interface is processed with an uneven shape, a pattern, printing decoration, etc., this is not the case, and the appearance and haze characteristics according to the use can be achieved. In this specification, the haze can be measured by the method described in the examples.

[0046] From the viewpoint of transparency, the total light transmittance of the laminate is preferably 90.0% or more, more preferably 91.0% or more. However, depending on the use of the laminate, when a matting agent, an antiglare agent, a coloring agent, a filler, etc. are blended in resin layer (A) and / or resin layer (B), or when the surface or interface is processed with an uneven shape, a pattern, printing decoration, etc., this is not the case. In this specification, the total light transmittance can be measured by the method described in the examples.

[0047] When the elongation of the laminate before stretching is 0%, the laminate has an elongation at break of 200% or more at 130°C to 160°C, and the haze of the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C is less than 3%. Thereby, the secondary formability in a wide temperature range is improved, the formability into a curved surface shape or a three-dimensional shape is excellent, and the occurrence of breakage, cracking, and whitening during stretching accompanying the secondary forming of the laminate is suppressed. The laminate preferably has a haze of 2.8% or less, more preferably 2.5% or less, and even more preferably 2.3% or less in the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C when the elongation of the laminate before stretching is 0% from the viewpoint of further improving the secondary formability in a wide temperature range. In the present specification, the elongation at break at a predetermined temperature and the haze of the stretched portion uniformly stretched at a predetermined elongation at a predetermined temperature can be measured by the method described in the examples.

[0048] From the viewpoint of further improving the secondary formability of the laminate in a wide temperature range, when the elongation of the laminate before stretching is 0%, the laminate preferably has a haze of less than 3%, more preferably 2.8% or less, even more preferably 2.5% or less, even more preferably 2.3% or less, and even more preferably 2.1% or less in the stretched portion uniformly stretched at an elongation of 200% at 140°C to 160°C.

[0049] Known methods can be used for laminating the resin layer (A) and the resin layer (B). For example, a method of laminating and molding the resin layer (A) and the resin layer (B) into a film by coextrusion, a method of molding the resin layer (A) and the resin layer (B) into films separately and then laminating them using a joining method such as adhesion and / or heat fusion after appropriately applying printing decoration, uneven shapes, etc. as required, a coating method in which the resin composition (A) is dissolved in a solvent and then coated on the surface of the resin layer (B) formed into a film to form the resin layer (A), or the resin composition (B) is dissolved in a solvent and then coated on the surface of the resin layer (A) formed into a film to form the resin layer (B), etc. can be mentioned. Among these, the coextrusion method, which is a melt processing method that does not use a solvent, is preferable in terms of productivity, control of the thickness of the laminate, environmental load, and cost, etc.

[0050] In the coextrusion method, the resin composition (A) and the resin composition (B) are extruded by separate extruders, the resin composition (A) and the resin composition (B) are made into a molten state, and the resin composition (A) and the resin composition (B) are laminated by a known method such as a feed block method or a multi-manifold method, introduced into a film forming die such as a T-die, formed into a film, and appropriately contacted with a polishing roll, a cooling roll, and / or a cooling belt, etc. to cool while forming a surface shape, whereby a film-like laminate can be obtained.

[0051] The laminate can be used as a decorative and / or protective film for decorating and / or protecting a molded body. The laminate may have a smooth surface, and within a range that does not inhibit the effects of the present invention, depending on the requirements of the application, on one or both sides of the film-like laminate, any surface shape such as a hairline, prism, uneven shape, three-dimensional decoration, matte surface, rough surface having a certain surface roughness, nailing at the film end, etc. may be provided. The provision of such a surface shape can be carried out by a known method. For example, a method of transferring the surface shape of a roll by sandwiching both sides of the film-like laminate immediately after extrusion or the molded film-like laminate fed out from a feeding device between two rolls or belts having a surface shape on at least one surface can be mentioned.

[0052] (Formed body) In one or more embodiments of the present invention, the formed body includes the laminate of one or more embodiments of the present invention described above, and the laminate is laminated on the surface of the formed body substrate. The laminate has an elongation at break of 200% or more at 130°C to 160°C, and the haze of the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C is less than 3%. By coating the formed body substrate having a non-planar curved surface shape or three-dimensional shape at least in part with the laminate, a resin formed body having a three-dimensional shape can be suitably obtained. Further, in the surface coating application of the formed body substrate having at least a part of a deep drawing shape that requires a high elongation rate, it can be preferably used without causing whitening or cracking of the coated portion. The laminate can protect and decorate the formed body by coating the formed body substrate in formed bodies having various shapes.

[0053] The formed body substrate is not particularly limited, but a thermoplastic resin substrate can be preferably used. The thermoplastic resin substrate may be composed of, for example, polycarbonate resin having a bisphenol skeleton, fluorene skeleton or isosorbide skeleton, acrylic resin, styrene resin (AS resin, ABS resin, MAS resin, styrene maleimide resin, styrene maleic anhydride resin, etc.), saturated polyester resin, polyvinyl chloride resin, polyarylate resin, PPS-based resin, POM-based resin, polyamide resin, polylactic acid resin, cellulose acylate-based resin, and polyolefin-based resin. Among them, one or more selected from the group consisting of polycarbonate resin, acrylic resin, styrene resin, and amorphous polyolefin-based resin are preferable because of their excellent transparency, and polycarbonate resin and / or acrylic resin are more preferable because of their good adhesion to the laminate. Polycarbonate resin is more preferable from the viewpoints of high rigidity, high heat resistance, high impact resistance, adhesion to the laminate during film insert injection molding or in-mold injection molding, and suppression of cloudiness at the interface between the laminate and the resin of the formed body substrate.

[0054] The molded body can be used, for example, as vehicle interior materials such as automobile interior materials, vehicle exterior materials such as automobile exterior materials, housings and exterior members of portable electronic devices and personal computers, and home appliance exterior materials. Specifically, the molded body may include a display portion of a display device or a cover member for the display portion, a sensor portion of a sensor device based on an optical, electromagnetic wave, ultrasonic, resistive film, or capacitance method, or a member covering the sensor portion.

[0055] The manufacturing method of the molded body is not particularly limited as long as it is a molding method capable of covering at least a part of the molded body base material, preferably a thermoplastic resin base material, with a laminate. Using a laminate, for example, an in-mold molding, a film insert injection molding, etc., a molded body with a laminate disposed on its surface can be manufactured. Also, before in-mold molding or film insert injection molding, if necessary, pre-forming of the laminate may be performed by methods such as vacuum molding, pressure-air molding, compression molding, etc. Alternatively, a so-called three-dimensional lamination molding may be performed in which the laminate is placed on the surface of a thermoplastic resin base material having a non-planar curved surface shape or three-dimensional shape in at least a part thereof by applying reduced pressure and / or pressure conditions to the laminate under heating. Furthermore, the laminate may be heated and laminated on the surface of the thermoplastic resin base material by hand while appropriately stretching to produce a resin molded body.

Example

[0056] Hereinafter, the present invention will be described in more detail based on examples. The present invention is not limited to these examples.

[0057] The measurement methods and evaluation methods used in the examples and comparative examples will be described.

[0058] (Glass transition temperature) A differential scanning calorimeter (DSC) SSC-5200 manufactured by Seiko Instruments was used. After the sample was once heated to 200°C at a rate of 25°C / min and then held for 10 minutes, After preliminary adjustment to lower the temperature to 50 °C at a rate of 25 °C / min, measurements were taken while raising the temperature to 200 °C at a heating rate of 10 °C / min. The differential value was obtained from the resulting DSC curve (SS DC), and the glass transition temperature was determined from its peak point.

[0059] (Gloss) The specular gloss at 60° was measured using a gloss meter VG7000 (manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS Z 8741.

[0060] (Thickness) The thickness (film thickness) of the laminate was measured using a PEACOCK dial gauge No25 (manufactured by Ozaki Seisakusho Co., Ltd.). Also, the ratio of the thickness of each layer of the laminate was determined by microscopic observation of the cross-section.

[0061] (Tensile test) The laminate was cut into pieces of 10 mm (width) × 100 mm (length) to obtain test specimens. For these test specimens, in a constant temperature room at 23 ± 0.5 °C, a tensile test was conducted using a Tensilon tensile testing machine (Shimadzu Corporation, AG-2000D) under the conditions of a chuck distance of 40 mm and a tensile speed of 200 mm / min, and the upper and lower yield point stresses, tensile fracture stress, and tensile fracture elongation in the MD direction were measured. The values of the upper and lower yield point stresses, tensile fracture stress, and tensile fracture elongation are the arithmetic mean values of three values excluding the highest and lowest values among the measurement results obtained using five test specimens, respectively.

[0062] (High-temperature tensile test) The laminate was cut into pieces measuring 10 mm (width) × 100 mm (length) to obtain test specimens. For these test specimens, using a tensilon tensile testing machine (Shimadzu Corporation, AG-2000D) equipped with a high-temperature bath set at a predetermined temperature, the test specimens were stretched to a predetermined elongation under the conditions of a preheating time of 2 minutes, a chuck distance of 40 mm, and a tensile speed of 200 mm / min. In accordance with the above-described method for measuring the tensile breaking elongation, stretching to elongations of 100%, 150%, and 200% was performed at a predetermined temperature using two test specimens for each elongation. The elongation was defined as 0% for no stretching, 100% when the chuck distance became twice the initial chuck distance (40 mm) (80 mm), 150% when it became 2.5 times (100 mm), and 200% when it became 3 times (120 mm). (Judgment of shape) Regarding the state of the stretched portion of the test specimen after stretching, the shape after stretching was judged according to the following judgment criteria A to D, and A was regarded as passing. A: No breakage. The stretching is uniform, and there is no non-uniform stretching (stretching unevenness) such as partial necking or whitening. B: No breakage. The stretching is not uniform, and there is stretching unevenness in one or more places in the stretched portion. C: One test specimen breaks. D: All test specimens break. (Haze after stretching) For those that were judged as A (pass) in the above shape judgment, the haze was measured at the center of the uniformly stretched portion.

[0063] (Total light transmittance and haze) The total light transmittance of the laminate, and the haze of the laminate and the laminate after stretching at a predetermined elongation were measured using a haze meter NDH4000 (manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS K 7375:2008 and JIS K 7136:2000, respectively.

[0064] (Crack resistance) At room temperature (23 °C), the presence or absence of cracks was observed when the laminate was bent 180° with the resin layer (A) on the inside, and the crack resistance was evaluated according to the following criteria. Good: No cracks Defective: Cracks are present

[0065] (Shape of the molded body after film insert injection molding) The laminate was cut into a size of 50 mm × 100 mm (width × length). On the surface of the movable side (the side opposite to the injection gate side) of a test mold in a flat plate shape of 50 mm × 150 mm × 5 mm (width × length × thickness) with an injection gate in the center of the plate, which was attached to an injection molding machine (「FNX180ECOJECT」manufactured by Nissei Plastic Industrial Co., Ltd.), two sides in the longitudinal direction of the cut laminate were fixed with Scotch (TM) mending tape so that the resin layer A was on the mold side. Polycarbonate resin (「H2000」manufactured by Mitsubishi Engineering Plastics) was injection molded here under the conditions of a cylinder temperature of 260°C to 300°C and a mold temperature of 80°C to obtain a flat plate-shaped molded body. The side surface of the obtained molded body on the side opposite to the injection gate side was observed, and the determination was made based on the following criteria. Good: The laminate and the injection resin are in good adhesion, and at the interface between the laminate and the injection resin, no appearance abnormalities such as cloudiness due to partial melting and flow of the laminate are observed. Defective: Cloudiness is observed at the interface between the laminate and the injection resin.

[0066] [Raw materials used] <Resin composition (A)> (A-1) Parapet HM (polymethyl methacrylate, manufactured by Kuraray Co., Ltd., 100% by weight of methyl methacrylate, glass transition temperature 119°C), which is a thermoplastic acrylic resin (a)-1, was used as resin composition A-1. (A-2) A glutarimide acrylic resin (imidation rate 13%, glass transition temperature 124°C) obtained by the method described in Production Example 5 of International Publication No. 2022 / 137768, which is a thermoplastic acrylic resin (a)-2, was used as resin composition A-2. <Resin composition (B)> (B-1) A commercially available polycarbonate resin composition (manufactured by Sumika Polycarbonate Ltd., product name "SP3002", glass transition temperature 123.5°C), which has bisphenol A polycarbonate resin (b) (weight average molecular weight of about 30,000) as the main component and contains an amorphous modified polyester resin (b2), was used as resin composition B-1. (B-2) A commercially available bisphenol A polycarbonate resin (manufactured by Mitsubishi Engineering-Plastics Corporation, product name "S2000", weight average molecular weight of about 30,000, glass transition temperature 149.4°C) was used as resin composition B-2. (B-3) A commercially available bisphenol A polycarbonate resin (manufactured by Sumika Polycarbonate Ltd., product name "TR1201A", weight average molecular weight of about 13,000, glass transition temperature 133.5°C) was used as resin composition B-3.

[0067] (Example 1) Using the resin composition (A) and resin composition (B) shown in Table 1 below, a laminate was produced by a coextrusion method. As the T-die used for coextruding the laminate, a 300 mm wide two-layer two-kind T-die (feed block method) was used. As the extruder for the resin composition (A) side, a 30 mmφ single-screw extruder was used, and melt-kneaded at a cylinder set temperature of 260 to 270°C. On the other hand, as the extruder for the resin composition (B) side, a 25 mmφ single-screw extruder was used, and melt-kneaded at a cylinder set temperature of 260°C. The molten resin composition (A) and resin composition (B) were introduced into the above die set at a die temperature of 260°C to discharge a laminated film, which was contacted with a casting roll set at 125°C and taken up to obtain a laminate (film roll) with a width of 250 mm, a thickness of the resin layer (A) made of the resin composition (A) of 40 μm, a thickness of the resin layer (B) made of the resin composition (B) of 160 μm, and a total thickness of the resin layer (A) and the resin layer (B) of 200 μm.

[0068] (Examples 2 to 3) A laminate was produced by the coextrusion method in the same manner as in Example 1, except that the resin layer (A) made of the resin composition (A) and the resin layer (B) made of the resin composition (B) had the thicknesses shown in Table 1 below.

[0069] (Examples 4 to 6) A laminate was produced by the coextrusion method in the same manner as in Example 1, except that the resin composition (A) shown in Table 1 below was used and the resin layer (A) made of the resin composition (A) and the resin layer (B) made of the resin composition (B) had the thicknesses shown in Table 1 below.

[0070] (Comparative Examples 1 to 4) A laminate was produced by the coextrusion method in the same manner as in Example 1, except that the resin composition (B) shown in Table 1 below was used and the resin layer (A) made of the resin composition (A) and the resin layer (B) made of the resin composition (B) had the thicknesses shown in Table 1 below.

[0071] For the laminates obtained in the examples and comparative examples, the optical properties, tensile properties, and high-temperature tensile properties were measured as described above, and the results are shown in Table 1 below. In Table 1 below, "-" means not measured.

[0072]

Table 1

[0073] As can be seen from Table 1 above, the laminate of the example has a haze in the thickness direction of less than 2%, a tensile elongation at break at 130°C to 160°C of 200% or more when the elongation before stretching is set to 0%, and a haze of the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C of less than 3%. It has good transparency, improved secondary moldability in a wide temperature range, and can suppress cracking, breaking, and whitening of the laminate during secondary molding.

[0074] On the other hand, the laminate of Comparative Example 1 has a tensile elongation at break of less than 200% at 130°C and 150°C, a haze of 3% or more in the stretched portion uniformly stretched at an elongation of 150% at 140°C and 160°C, and poor secondary moldability at 130°C to 160°C. The laminates of Comparative Examples 2 and 3 have a tensile elongation at break of less than 200% at 130°C, 140°C and 150°C, and poor secondary moldability at 130°C to 160°C. The laminate of Comparative Example 4 has a tensile elongation at break of less than 200% at 130°C and 140°C, and poor secondary moldability at 130°C to 160°C. Further, the laminate of Comparative Example 4 has poor crack resistance.

[0075] The present invention is not particularly limited, and may include, for example, the following embodiments.

[0076] [1] A laminate comprising a resin layer (A) and a resin layer (B), wherein the resin layer (A) is composed of a resin composition (A) containing a thermoplastic acrylic resin (a) containing 50% by weight or more of methyl methacrylate units, the resin layer (B) is composed of a resin composition (B) containing a polycarbonate resin (b), the thickness of the laminate is 350 μm or less, the haze in the thickness direction of the laminate is less than 2%, when the elongation of the laminate before stretching is set to 0%, the tensile elongation at break at 130°C to 160°C is 200% or more, and the haze of the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C is less than 3%. [2] The laminate according to [1], wherein the polycarbonate resin (b) contains 80% by weight or more of a structural unit composed of a carbonate ester of a dihydric phenol compound. [3] The laminate according to [1] or [2], wherein the content of the polycarbonate resin (b) in the resin composition (B) is 50 to 99% by weight. [4] The laminate according to any one of [1] to [3], wherein the glass transition temperature of the resin composition (B) is 130°C or lower. [5] The laminate according to any one of [1] to [4], wherein the content of methyl methacrylate units in the thermoplastic acrylic resin (a) is 80% by weight or more. [6] The laminate according to any one of [1] to [5], wherein the content of the thermoplastic acrylic resin (a) in the resin composition (A) is 50% by weight or more. [7] The laminate according to [6], wherein the content of the thermoplastic acrylic resin (a) in the resin composition (A) is 80% by weight or more. [8] The laminate according to any one of [1] to [7], wherein the thickness ratio of the resin layer (A) to the resin layer (B) (resin layer (A) / resin layer (B)) is from 97 / 3 to 5 / 95. [9] The laminate according to any one of [1] to [8], wherein the resin composition (B) further contains a transparent thermoplastic resin (b2) in addition to the polycarbonate resin (b).

[10] The laminate according to [9], wherein the transparent thermoplastic resin (b2) is at least one selected from the group consisting of polyester resins and polycarbonate resins (excluding the polycarbonate resin (b)).

[11] The laminate according to

[10] , wherein the transparent thermoplastic resin (b2) is an amorphous polyester resin.

[12] The transparent thermoplastic resin (b2) is an amorphous polyester resin containing ethylene glycol units and terephthalic acid units as constituent units, and further containing one or more constituent units selected from the group consisting of cyclohexanedimethanol units and isophthalic acid units; an amorphous polyester resin containing cyclohexanedimethanol units and terephthalic acid units as constituent units; and an amorphous polyester resin containing cyclohexanedimethanol units and terephthalic acid units as constituent units and further containing one or more constituent units selected from the group consisting of ethylene glycol units and isophthalic acid units, and is one or more selected from the group consisting of the above. The laminate according to

[11] .

[13] The laminate according to any one of [1] to

[12] , further comprising one or more functional layers selected from the group consisting of a hard coat layer, an antireflection layer, an antiglare layer, an antifouling layer, an antistatic layer, a conductive layer, an adhesive layer, a printing layer, and a decorative layer.

[14] A molded article comprising the laminate according to any one of [1] to

[13] and a molded article substrate. The laminate is laminated on the surface of the molded article substrate.

[15] The molded article according to

[14] , wherein at least a part of the surface of the molded article substrate on which the laminate is laminated has a curved surface shape or a three-dimensional shape.

[16] The molded article according to any one of

[14] to

[15] , including a display part of a display device or a cover member of the display part.

[17] The molded article according to any one of

[14] to

[16] , including a sensor part of a sensor device based on an optical, electromagnetic wave, ultrasonic, resistive film, or capacitance method, or a member covering the sensor part.

[0077] Each of the embodiments described above is not independent, and it goes without saying that excessive explanation is unnecessary. Those skilled in the art can appropriately combine them. Furthermore, components from different embodiments may be appropriately combined.

Claims

1. A laminate comprising a resin layer (A) and a resin layer (B), wherein the resin layer (A) is composed of a resin composition (A) containing a thermoplastic acrylic resin (a) containing 50% by weight or more of methyl methacrylate units, the resin layer (B) is composed of a resin composition (B) containing a polycarbonate resin (b), the thickness of the laminate is 350 μm or less, the haze in the thickness direction of the laminate is less than 2%, when the elongation before stretching of the laminate is set to 0%, the tensile fracture elongation at 130°C to 160°C is 200% or more, and the haze of the stretched portion uniformly stretched at an elongation of 150% at 130°C to 160°C is less than 3%, the laminate.

2. The laminate according to claim 1, wherein the polycarbonate resin (b) contains 80% by weight or more of a structural unit composed of a carbonate ester of a dihydric phenol compound.

3. The laminate according to claim 1, wherein the content of the polycarbonate resin (b) in the resin composition (B) is 50 to 99% by weight.

4. The laminate according to claim 1, wherein the glass transition temperature of the resin composition (B) is 130°C or lower.

5. The laminate according to claim 1, wherein the content of methyl methacrylate units in the thermoplastic acrylic resin (a) is 80% by weight or more.

6. The laminate according to claim 1, wherein the content of the thermoplastic acrylic resin (a) in the resin composition (A) is 50% by weight or more.

7. The laminate according to claim 6, wherein the content of the thermoplastic acrylic resin (a) in the resin composition (A) is 80% by weight or more.

8. The laminate according to claim 1, wherein the thickness ratio of the resin layer (A) to the resin layer (B) (resin layer (A) / resin layer (B)) is 97 / 3 to 5 / 95.

9. The laminate according to claim 1, wherein the resin composition (B) further contains a transparent thermoplastic resin (b2) in addition to the polycarbonate resin (b).

10. The laminate according to claim 9, wherein the transparent thermoplastic resin (b2) is at least one selected from the group consisting of a polyester resin and a polycarbonate resin (excluding the polycarbonate resin (b)).

11. The laminate according to claim 10, wherein the transparent thermoplastic resin (b2) is an amorphous polyester resin.

12. The transparent thermoplastic resin (b2) is A polyester resin containing ethylene glycol units and terephthalic acid units as constituent units, further comprising one or more constituent units selected from the group consisting of cyclohexanedimethanol units and isophthalic acid units, an amorphous polyester resin An amorphous polyester resin containing cyclohexanedimethanol units and terephthalic acid units as constituent units, and A polyester resin containing cyclohexanedimethanol units and terephthalic acid units as constituent units, further comprising one or more constituent units selected from the group consisting of ethylene glycol units and isophthalic acid units, an amorphous polyester resin, wherein the laminate according to claim 11 is one or more selected from the group consisting of

13. The laminate according to claim 1, further comprising one or more functional layers selected from the group consisting of a hard coat layer, an antireflection layer, an antiglare layer, an antifouling layer, an antistatic layer, a conductive layer, an adhesive layer, a printing layer, and a decorative layer

14. A laminate according to any one of claims 1 to 13, and a molded body substrate, wherein The laminate is laminated on the surface of the molded body substrate, a molded body

15. In the molded body substrate, at least a part of the surface on which the laminate is laminated has a curved surface shape or a three-dimensional shape, the molded body according to claim 14

16. A molded body according to claim 14, including a display portion of a display device or a cover member of the display portion

17. A sensor portion of a sensor device based on an optical, electromagnetic wave, ultrasonic, resistive film, or capacitance method, or a member covering the sensor portion, the molded body according to claim 14

Images