Multilayer body and hot-formed molding

Abstract

To provide a multilayer body having an acrylic resin layer, excellent toughness and reduced whitening and to provide a hot-formed molding.SOLUTION: A multilayer body of the present invention includes: an acrylic resin layer containing a (meth)acryl resin; and a polycarbonate resin layer containing a polycarbonate resin. The acrylic resin layer contains 1 to 50 mass% of elastomer. The multilayer body has a haze of less than or equal to 3%. The acrylic resin layer has a thickness of 20 to 80 μm. An expression (1) is satisfied where PCt is a thickness of the polycarbonate resin layer and Act is the thickness of the acrylic resin layer: 0.1≤Act / PCt≤0.8 ...Ex (1).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a multilayer body and a heat-molded body, and in particular to a multilayer body having a polycarbonate resin layer and an acrylic resin layer. [Background technology]

[0002] Acrylic resins, such as polymethyl methacrylate (PMMA), are widely used as materials with high surface hardness and high transparency, but they suffer from poor toughness. Therefore, studies have been conducted on resin compositions in which the toughness of acrylic resins has been improved (Patent Document 1, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-132705 Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, a layer containing an acrylic resin (acrylic resin layer) has high surface hardness but tends to have poor toughness. To improve toughness, it is conceivable to blend an elastomer into the acrylic resin layer. However, when a small amount of elastomer is blended into the acrylic resin layer, sufficient improvement in toughness cannot be obtained, and when the amount is increased, the acrylic resin layer tends to whiten. The present invention aims to solve such problems and to provide a multilayer body having an acrylic resin layer, which has excellent toughness and suppresses whitening, and a heat-molded body. [Means for solving the problem]

[0005] In view of the above problems, the present inventors have conducted research and found that the above problems can be solved by the following means. [1] A multilayer body comprising an acrylic resin layer containing a (meth)acrylic resin and a polycarbonate resin layer containing a polycarbonate resin, the acrylic resin layer contains 1 to 50% by mass of an elastomer, A multilayer body, wherein the haze of the multilayer body is 3% or less. [2] The multilayer body according to [1], wherein the thickness of the acrylic resin layer is 20 to 80 μm. [3] The multilayer body according to [1] or [2], wherein the acrylic resin layer has a pencil hardness of F or more. [4] The multilayer body according to any one of [1] to [3], wherein when the thickness of the polycarbonate resin layer is PCt and the thickness of the acrylic resin layer is Act, formula (1) is satisfied. Formula (1): 0.1≦Act / PCt≦0.8 [5] The multilayer body according to any one of [1] to [4], wherein the multilayer body has a haze of 2% or less. [6] The thickness of the acrylic resin layer is 20 to 80 μm, The acrylic resin layer has a pencil hardness of F or more, When the thickness of the polycarbonate resin layer is PCt and the thickness of the acrylic resin layer is Act, formula (1) is satisfied, The multilayer body according to [1], wherein the haze of the multilayer body is 2% or less. Formula (1): 0.1≦Act / PCt≦0.8 [7] The multilayer body according to any one of [1] to [6], wherein the elastomer comprises a block copolymer having a hard segment and a soft segment. [8] The multilayer body according to any one of [1] to [6], wherein the elastomer comprises an acrylic block copolymer and / or a thermoplastic polyurethane elastomer. [9] The multilayer body according to any one of [1] to [8], wherein the multilayer body has a breaking elongation at 23°C of 15% or more.

[10] The multilayer body according to any one of [1] to [9], which does not have a polarizer and / or a polyester resin layer.

[11] A heat-molded article obtained by heat-processing the multilayer article according to any one of [1] to [9]. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a multilayer body and a hot-molded body that are excellent in toughness and suppressed in whitening. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram schematically illustrating the layer structure of the multilayer body of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. In this specification, the symbol "to" is used to mean that the numerical values ​​before and after it are included as upper and lower limits. "A to B" means that the range is A or more and B or less. In addition, any combination of the upper and lower limit values ​​of the numerical values ​​in this specification is an example of this embodiment. In this specification, unless otherwise specified, the weight average molecular weight and number average molecular weight are values ​​measured by GPC (gel permeation chromatography) in terms of polystyrene. In this specification, "(meth)acrylate" refers to both or either of acrylate and methacrylate. The term "multilayer body" as used herein is intended to include a flat molded body in the form of a film or a sheet. "Film" and "sheet" refer to a molded article that is thin relative to its length and width, and is generally flat. In addition, the "film" and "sheet" as used herein may be single-layer or multi-layer. If the measurement methods, etc. described in the standards shown in this specification change depending on the year, they will be based on the standards in effect as of January 1, 2024, unless otherwise specified. If the measurement methods, etc. described in the standards shown in this specification are abolished as of January 1, 2024, they will be based on the standards in effect at the time of abolition. The scale of Figure 1 may not be consistent with reality.

[0009] The multilayer body of the present embodiment is a multilayer body including an acrylic resin layer containing a (meth)acrylic resin (sometimes simply referred to as an "acrylic resin layer" in this specification) and a polycarbonate resin layer containing a polycarbonate resin (sometimes simply referred to as a "polycarbonate resin layer" in this specification), and is characterized in that the acrylic resin layer contains 1 to 50 mass % of an elastomer, and the haze of the multilayer body is 3% or less. By adopting such a configuration, it is possible to provide a multilayer body that is excellent in toughness and suppresses whitening. As described above, one approach to improving the elongation at break of the acrylic resin layer is to incorporate an elastomer into the acrylic resin layer. However, incorporating an elastomer into the acrylic resin layer tends to cause the acrylic resin layer to whiten. This is thought to be due to the high amount of elastomer incorporated and the large dispersion diameter of the elastomer. To prevent whitening, it has been considered to reduce the amount of elastomer incorporated or to use an elastomer that is finely dispersed. However, when attempting to make such improvements, the effect of the elastomer, i.e., the effect of improving the elongation at break, may not be fully achieved. Under these circumstances, in this embodiment, a multilayer structure of an acrylic resin layer and a polycarbonate resin layer is used. That is, by overlaying a polycarbonate resin layer on an acrylic resin layer, even when the elastomer in the acrylic resin layer is in the above-mentioned state, it is possible to improve the breaking elongation of the multilayer structure and suppress whitening. Furthermore, the improved breaking elongation also improved formability, and it was found to be useful for heat-processed products and even heat-bent products.

[0010] Hereinafter, the embodiments of the present invention will be described in detail. However, the explanation of the constituent elements described below is an example of an embodiment of the present invention, and the present invention is not limited to these contents.

[0011] <Acrylic resin layer containing (meth)acrylic resin> The multilayer body of this embodiment includes an acrylic resin layer containing a (meth)acrylic resin and an elastomer. By including the acrylic resin layer, a multilayer body having high surface hardness can be obtained.

[0012] As described above, the acrylic resin layer in this embodiment contains an acrylic resin. An example of the acrylic resin is preferably a polymer containing alkyl (meth)acrylate units (preferably alkyl methacrylate units) in an amount of 50% by mass or more (preferably 90% by mass or more, and preferably 100% by mass or less) of all structural units, and more preferably a polymer containing methyl (meth)acrylate units (preferably methyl methacrylate units) in an amount of 50% by mass or more (preferably 90% by mass or more, and preferably 100% by mass or less) of all structural units. Examples of structural units other than alkyl (meth)acrylate units include other (meth)acrylate units, styrene units, cyclic acid anhydride units, N-substituted maleimide units, and lactone ring units.

[0013] Examples of acrylic resins include resin (A) described in paragraphs 0010 to 0020 and resin (B) described in paragraphs 0022 to 0034 of JP 2021-80345 A, the descriptions in paragraphs 0010 to 0027 and 0029 to 0041 of WO 2021 / 100660, copolymer resin (A) described in paragraphs 0010 to 0028 and copolymer resin (B) described in paragraphs 0029 to 0042 of WO 2021 / 100661, and the descriptions in paragraphs 0024 to 0029 of JP 2022-158929 A, the contents of which are incorporated herein by reference.

[0014] The acrylic resin layer may be made of only an acrylic resin and an elastomer, or may contain other thermoplastic resins (excluding those corresponding to elastomers) in addition to the acrylic resin and the elastomer. The other thermoplastic resin preferably includes at least one thermoplastic resin selected from a styrene-based resin, a fluorine-based resin such as polyvinylidene fluoride, and an aromatic polyether resin such as polyphenylene ether, and more preferably includes a styrene-based resin.

[0015] An example of an acrylic resin layer is a layer whose 90% by mass or more (preferably 95% by mass or more, more preferably 97% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more) is composed of acrylic resin and elastomer.

[0016] The weight-average molecular weight of the acrylic resin is not particularly limited, but is preferably 10,000 or more, more preferably 30,000 or more, even more preferably 50,000 or more, even more preferably 60,000 or more, and even more preferably 70,000 or more. The weight-average molecular weight of the acrylic resin is preferably 250,000 or less, more preferably 200,000 or less, even more preferably 150,000 or less, even more preferably 100,000 or less, and even more preferably 90,000 or less.

[0017] The glass transition temperature of the acrylic resin layer used in this embodiment is preferably 80° C. or higher, more preferably 90° C. or higher, even more preferably 95° C. or higher, even more preferably 100° C. or higher, and even more preferably 105° C. or higher. There is no particular upper limit, but a practical value is, for example, 200° C. or lower. The glass transition temperature of the acrylic resin layer is measured according to the description in paragraph 0056 of JP 2022-080270 A.

[0018] The acrylic resin layer in this embodiment contains an elastomer, which can increase the elongation at break of the resulting multilayer body. The elastomer preferably comprises a block copolymer having hard and soft segments. The elastomer preferably contains at least one selected from the group consisting of a styrene-based thermoplastic elastomer, an acrylic block copolymer, a thermoplastic polyurethane elastomer, and an olefin-based thermoplastic elastomer, and more preferably contains an acrylic block copolymer and / or a thermoplastic polyurethane elastomer.

[0019] The acrylic block copolymer preferably contains a polymer block containing an acrylic acid ester monomer unit and / or a polymer block containing a methacrylic acid ester monomer unit, and may further contain other polymer blocks.

[0020] A polymer block containing an acrylic acid ester monomer unit is a polymer block in which the acrylic acid ester monomer unit is the largest among all monomer units. A polymer block containing an acrylic acid ester monomer unit may contain a unit of a monomer (another monomer) other than an acrylic acid ester monomer, as necessary. It is preferable that a polymer block containing an acrylic acid ester monomer unit does not contain a methacrylic acid ester monomer unit. Examples of the acrylic acid ester monomer include acrylic acid esters such as methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, phenyl acrylate, dimethylaminoethyl acrylate, etc. Among these, alkyl acrylates are preferred, and n-butyl acrylate is more preferred. These acrylic acid ester monomers may be used alone or in combination of two or more.

[0021] The other monomer that can be contained in the polymer block containing an acrylic acid ester monomer unit is not particularly limited as long as it is copolymerizable with the acrylic acid ester monomer, and examples thereof include (meth)acrylic acid, glycidyl (meth)acrylate, allyl (meth)acrylate, aromatic vinyl monomers, and vinyl cyanide monomers. These other monomers may be used alone or in combination of two or more.

[0022] The proportion of the acrylic acid ester monomer units relative to the total mass of all monomer units constituting the polymer block containing the acrylic acid ester monomer units is preferably 60 to 100 mass%, more preferably 80 to 100 mass%, even more preferably 90 to 100 mass%, and particularly preferably 95 to 100 mass%. The proportion of other monomer units relative to the total mass of all monomer units constituting the polymer block containing the acrylate monomer units is preferably 0 to 40 mass%, more preferably 0 to 20 mass%, even more preferably 0 to 10 mass%, and particularly preferably 0 to 5 mass%.

[0023] The methacrylic acid ester monomer unit is a polymer block in which the methacrylic acid ester monomer unit is the most abundant among all the monomer units. The methacrylic acid ester monomer unit may contain a unit of a monomer (another monomer) other than the methacrylic acid ester monomer, as necessary. It is preferable that the methacrylic acid ester monomer unit does not contain an acrylic acid ester monomer unit. Examples of methacrylic acid ester monomers include methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, octyl methacrylate, nonyl methacrylate, octadecyl methacrylate, dodecyl methacrylate, and 2-ethylhexyl methacrylate. Among these, alkyl methacrylates are preferred, and methyl methacrylate is more preferred. These methacrylic acid ester monomers may be used alone or in combination of two or more.

[0024] The other monomer that can be contained in the methacrylic acid ester monomer unit is not particularly limited as long as it is copolymerizable with the methacrylic acid ester monomer, and examples thereof include (meth)acrylic acid, glycidyl (meth)acrylate, allyl (meth)acrylate, aromatic vinyl monomers, and vinyl cyanide monomers. These other monomers may be used alone or in combination of two or more.

[0025] The proportion of the methacrylic acid ester monomer units relative to the total mass of all monomer units constituting the methacrylic acid ester monomer units is preferably 60 to 100 mass%, more preferably 80 to 100 mass%, even more preferably 90 to 100 mass%, and particularly preferably 95 to 100 mass%. The proportion of other monomer units relative to the total mass of all monomer units constituting the methacrylic acid ester monomer units is preferably 0 to 40 mass%, more preferably 0 to 20 mass%, even more preferably 0 to 10 mass%, and still more preferably 0 to 5 mass%.

[0026] The polymer blocks other than the polymer block containing an acrylic acid ester monomer unit and / or the polymer block containing a methacrylic acid ester monomer unit contain units of a monomer (other monomer) other than an acrylic acid ester monomer unit and a methacrylic acid ester monomer unit. Examples of other monomers include (meth)acrylic acid, glycidyl (meth)acrylate, allyl (meth)acrylate, aromatic vinyl monomers, and vinyl cyanide monomers. These other monomers may be used alone or in combination of two or more. The elastomer used in this embodiment may be configured to be substantially free of a core-shell elastomer. "Substantially free" means that the content of the core-shell elastomer is less than 5% by mass, preferably less than 3% by mass, more preferably less than 1% by mass, and even more preferably less than 0.1% by mass of the total elastomer content of the resin composition of this embodiment.

[0027] The thermoplastic polyurethane elastomer is synthesized from an isocyanate and a compound having a hydroxyl group, and preferably has hard and soft segments. The use of a thermoplastic polyurethane elastomer enables a more balanced improvement in both TD and MD elongation at break. The hard segment is a segment composed of an isocyanate (preferably a diisocyanate) and a polyol (preferably a diol) having 1 to 5 carbon atoms. The isocyanate may be any of aromatic isocyanate, aliphatic isocyanate, and alicyclic isocyanate, but aliphatic isocyanate and / or alicyclic isocyanate are preferred, and alicyclic isocyanate is more preferred. The soft segment is a segment composed of an isocyanate (preferably a diisocyanate) and a long-chain polyol (preferably a long-chain diol). Examples of long-chain polyols include polyester polyols, polyether polyols, and polycarbonate polyols.

[0028] In addition to the above, the elastomers may be referred to in paragraph 0021 of JP 2015-151483 A, paragraph 0026 of JP 2014-040540 A, paragraph 0026 of JP 2024-024789 A, paragraphs 0055 to 0058 of JP 2024-019126 A, and paragraphs 0042 to 0045 of JP 2023-037520 A, the contents of which are incorporated herein by reference.

[0029] The acrylic resin layer in this embodiment contains 1 to 50% by mass of elastomer, relative to 100% by mass of the acrylic resin layer. The lower limit is preferably 3% by mass or more, more preferably 5% by mass or more, even more preferably 7% by mass or more, even more preferably 9% by mass or more, and even more preferably 11% by mass or more depending on the intended use. The upper limit is preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less, even more preferably 15% by mass or less, and even more preferably 14% by mass or less depending on the intended use. By setting the content at or above the lower limit, the breaking elongation of the resulting multilayer body tends to be further improved. Furthermore, by setting the content at or below the upper limit, the transparency of the acrylic resin layer tends to be further improved. The acrylic resin layer in the present embodiment may contain only one type of elastomer, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0030] In addition to the above components, the acrylic resin layer may contain flame retardants, antioxidants, release agents, UV absorbers, heat stabilizers, flame retardants, flame retardant aids, colorants, antistatic agents, fluorescent brighteners, antifogging agents, flow improvers, plasticizers, dispersants, antibacterial agents, antiblocking agents, impact improvers, sliding improvers, color improvers, acid trapping agents, etc. These components may be used alone or in combination of two or more. The total content of the above components is preferably 0 to 5% by mass of the polycarbonate resin layer, more preferably 0 to 3% by mass, even more preferably 0 to 1% by mass, even more preferably 0 to 0.5% by mass, even more preferably 0 to 0.3% by mass, and even more preferably 0 to 0.1% by mass.

[0031] Examples of antioxidants that may be contained in the acrylic resin layer include phenol-based antioxidants, amine-based antioxidants, phosphorus-based antioxidants, and thioether-based antioxidants. Among these, phosphorus-based antioxidants and phenol-based antioxidants (more preferably hindered phenol-based antioxidants) are preferred in the present invention. Phosphorus-based antioxidants are particularly preferred because they provide excellent color to the molded product.

[0032] The phosphorus-based antioxidant is preferably a phosphite-based antioxidant, and more preferably a phosphite-based antioxidant represented by the following formula (P1) or (P2). Formula (P1) [ka] (In formula (P1), R 11 and R 12 each independently represents an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms. Formula (P2) [ka] (In formula (P2), R 13 ~R 17 each independently represents a hydrogen atom, an aryl group having 6 to 20 carbon atoms, or an alkyl group having 1 to 20 carbon atoms.

[0033] In the above formula (P1), R 11 , R 12 Each of the alkyl groups represented by R is preferably a linear or branched alkyl group having 1 to 10 carbon atoms. 11 , R 12 When is an aryl group, it is preferably an aryl group represented by any one of the following formulae (1-a), (1-b), and (1-c): In the formula, * represents the bonding position.

[0034] [ka] (In formula (1-a), R Aeach independently represents an alkyl group having 1 to 10 carbon atoms. B each independently represents an alkyl group having 1 to 10 carbon atoms.

[0035] For the hindered phenol-based antioxidant, reference can be made to the descriptions in paragraph 0063 of JP-A-2018-090677 and paragraph 0076 of JP-A-2018-188496, the contents of which are incorporated herein by reference.

[0036] In addition to the above, the antioxidants can be found in paragraphs 0057 to 0061 of JP 2017-031313 A, the contents of which are incorporated herein by reference.

[0037] Examples of release agents that may be contained in the acrylic resin layer include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, polyethers having a number average molecular weight of 100 to 5,000, and polysiloxane-based silicone oils. In addition to the above, the release agent may be described in paragraphs 0035 to 0039 of WO 2015 / 190162, the contents of which are incorporated herein by reference.

[0038] The thickness of the acrylic resin layer in this embodiment is preferably 20 μm or more, more preferably 24 μm or more, even more preferably 25 μm or more, even more preferably 35 μm or more, even more preferably 45 μm or more, even more preferably 50 μm or more, and is preferably 80 μm or less, more preferably 75 μm or less, even more preferably 70 μm or less, even more preferably 65 μm or less, and even more preferably 60 μm or less. The multilayer body of the present embodiment may have only one acrylic resin layer, or may have two or more acrylic resin layers. When having two or more layers, it is preferable that the total thickness is within the above range.

[0039] The pencil hardness of the acrylic resin layer in this embodiment is preferably F or more, more preferably H or more, and even more preferably 2H or more. There is no particular upper limit to the pencil hardness of the acrylic resin layer, but even if it is 3H or less, the required performance is sufficiently satisfied. In this embodiment, the content of the elastomer in the acrylic resin layer can be reduced, so that a high pencil hardness can be achieved.

[0040] <Polycarbonate resin layer containing polycarbonate resin> The multilayer body of this embodiment includes a polycarbonate resin layer containing a polycarbonate resin. By providing the polycarbonate resin layer, the breaking elongation of the multilayer body can be improved.

[0041] The polycarbonate resin is not particularly limited as long as it contains an -[OR-OCO]- structural unit (R is a hydrocarbon group (for example, an aliphatic group, an aromatic group, or one containing both an aliphatic group and an aromatic group, and further one having a linear or branched structure)) that contains a carbonate ester bond in the molecular main chain, and various polycarbonate resins can be used.

[0042] In this embodiment, the polycarbonate resin preferably contains a bisphenol-type polycarbonate resin. A bisphenol-type polycarbonate resin is one in which 80 mol % or more, preferably 90 mol % or more, and more preferably 95 mol % or more of the structural units constituting the polycarbonate resin are carbonate structural units derived from bisphenol and / or its derivatives. The bisphenol here is preferably bisphenol A and / or bisphenol AP, and more preferably bisphenol A. The bisphenol polycarbonate resin is preferably a bisphenol A polycarbonate resin and / or a bisphenol AP polycarbonate resin, and more preferably a bisphenol A polycarbonate resin.

[0043] The polycarbonate resin used in this embodiment may contain a polycarbonate resin having a terminal structure represented by formula (PC1). By having such a terminal structure, the glass transition temperature is lowered while maintaining the toughness of the material, and a multilayer body having excellent thermal processability (particularly, thermal bending property) can be obtained. Note that a polycarbonate resin having a terminal structure represented by formula (PC1) means that at least one of its terminals has the terminal structure represented by formula (PC1). As an example of this embodiment, it is preferable that 50 mol % or more of the polycarbonate resin contained in the polycarbonate resin layer has at least one of the above terminal structures. Formula (PC1) [ka] (In formula (PC1), R 1 represents an alkyl group having 8 to 36 carbon atoms or an alkenyl group having 8 to 36 carbon atoms, and R 2 represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and n is an integer of 0 to 4.

[0044] R 1 is preferably an alkyl or alkenyl group having 12 or more carbon atoms, and more preferably an alkyl or alkenyl group having 14 or more carbon atoms. 1 R is preferably an alkyl or alkenyl group having 22 or less carbon atoms, and more preferably an alkyl or alkenyl group having 18 or less carbon atoms. 1 is preferably an alkyl group. R 2 is preferably a fluorine atom, a chlorine atom, a methyl group, an ethyl group, or a phenyl group, and more preferably a fluorine atom, a chlorine atom, or a methyl group. n is preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.

[0045] The terminal structure represented by formula (PC1) can be added to a polycarbonate resin by using a terminal terminator. For details, see paragraphs 0022 to 0030 of JP 2019-2023 A, the contents of which are incorporated herein by reference.

[0046] The molecular weight of the polycarbonate resin is not particularly limited, but is preferably 20,000 or more, more preferably 22,000 or more, in terms of viscosity average molecular weight calculated from the solution viscosity measured at 25°C using methylene chloride as a solvent. The viscosity average molecular weight is preferably 35,000 or less, more preferably 32,000 or less, and even more preferably 30,000 or less. By setting the viscosity average molecular weight at or above the lower limit, the strength of the resulting flat-plate molded article can be increased. By setting the viscosity average molecular weight at or below the upper limit, moldability tends to be improved. Here, the viscosity average molecular weight [Mv] is determined by using methylene chloride as a solvent and an Ubbelohde viscometer to determine the intrinsic viscosity [η] (unit: dL / g) at a temperature of 25°C, and then calculating it using the Schnell viscosity formula, i.e., η = 1.23 × 10 -4 Mv 0.83 The intrinsic viscosity [η] is the specific viscosity [η] at each solution concentration [C] (g / dL). sp ] was measured and the value was calculated according to the following formula.

number

[0047] The onset glass transition temperature (Tg) of the polycarbonate resin used in this embodiment is preferably 160° C. or lower, more preferably 155° C. or lower, even more preferably 154° C. or lower, even more preferably 153° C. or lower, even more preferably 152° C. or lower, and even more preferably 151° C. or lower. The onset glass transition temperature (Tg) of the polycarbonate resin used in this embodiment is, for example, 120° C. or higher, and may be 130° C. or higher, 140° C. or higher, 143° C. or higher, 145° C. or higher, 147° C. or higher, or 148° C. or higher. The glass transition temperature of the polycarbonate resin is measured according to the description in paragraph 0056 of JP-A-2022-080270.

[0048] For details of the polycarbonate resin, reference can be made to paragraphs 0011 to 0020 of JP-A-2012-144604 and paragraphs 0014 to 0035 of JP-A-2019-002023, the contents of which are incorporated herein by reference, as long as they do not deviate from the spirit of this embodiment.

[0049] The content of polycarbonate resin in the polycarbonate resin layer in this embodiment is preferably 90% by mass or more, more preferably 92% by mass or more, even more preferably 94% by mass or more, still more preferably 96% by mass or more, and even more preferably 97% by mass or more, and may be 98% by mass or more, or 100% by mass or less, based on 100% by mass of the polycarbonate resin layer. When the polycarbonate resin layer in this embodiment contains two or more types of polycarbonate resins, the total amount thereof preferably falls within the above range.

[0050] In addition to the above components, the polycarbonate resin layer in this embodiment may contain antioxidants, release agents, UV absorbers, flame retardants, flame retardant aids, heat stabilizers, colorants, antistatic agents, fluorescent brighteners, antifogging agents, flow improvers, plasticizers, dispersants, antibacterial agents, antiblocking agents, impact improvers, sliding improvers, color improvers, acid trapping agents, etc. These components may be used alone or in combination of two or more. The total content of the above components is preferably 0 to 5% by mass of the polycarbonate resin layer, more preferably 0 to 3% by mass, even more preferably 0 to 1% by mass, even more preferably 0 to 0.5% by mass, even more preferably 0 to 0.3% by mass, and even more preferably 0 to 0.1% by mass.

[0051] Examples of antioxidants include phenol-based antioxidants, amine-based antioxidants, phosphorus-based antioxidants, and thioether-based antioxidants. Among these, in the present embodiment, phosphorus-based antioxidants and phenol-based antioxidants (more preferably hindered phenol-based antioxidants) are preferred.

[0052] For the hindered phenol-based antioxidant, reference can be made to the descriptions in paragraph 0063 of JP-A-2018-090677 and paragraph 0076 of JP-A-2018-188496, the contents of which are incorporated herein by reference.

[0053] In addition to the above, the antioxidants can be found in paragraphs 0057 to 0061 of JP 2017-031313 A, the contents of which are incorporated herein by reference.

[0054] For details about the release agent, please refer to paragraphs 0035 to 0039 of WO 2015 / 190162, the contents of which are incorporated herein by reference.

[0055] The thickness of the polycarbonate resin layer is preferably 50 μm or more, more preferably 100 μm or more, even more preferably 150 μm or more, and even more preferably 180 μm or more. By making the thickness equal to or greater than the lower limit, molding becomes easier. Furthermore, the upper limit of the thickness of the polycarbonate resin layer is preferably 1000 μm or less, more preferably 750 μm or less, even more preferably 500 μm or less, and even more preferably 300 μm or less.

[0056] The multilayer body of this embodiment preferably satisfies formula (1) when the thickness of the polycarbonate resin layer is PCt (unit: μm) and the thickness of the acrylic resin layer is Act (unit: μm). Formula (1): 0.1≦Act / PCt≦0.8 When Act / PCt is 0.1 or more, the surface hardness of the multilayer body tends to be further improved, and when Act / PCt is 0.8 or less, the formability of the multilayer body tends to be further improved. The Act / PCt ratio is preferably 0.15 or more, and is preferably 0.6 or less, more preferably 0.5 or less, even more preferably 0.4 or less, and even more preferably 0.3 or less.

[0057] <Physical properties of multilayer bodies> The multilayer body of this embodiment has excellent transparency. Specifically, the multilayer body of this embodiment has a haze of 3% or less, preferably 2% or less, more preferably 1% or less, even more preferably 0.8% or less, and even more preferably 0.4% or less. The lower limit of the haze of the multilayer body is ideally 0%, but practically 0.001% or more. Such a low haze can be achieved by reducing the amount of elastomer used in the acrylic resin layer or by using an elastomer with a relatively small dispersion diameter. In this embodiment, the haze is measured by the method described in the examples.

[0058] The multilayer body of this embodiment preferably has a breaking elongation at 23°C of 15% or more, more preferably 20% or more, and even more preferably 30% or more. There is no particular upper limit to the breaking elongation, but for example, 90% or less, even 80% or less, and particularly 75% or less is a sufficient practical level. Such a high breaking elongation can be achieved by blending an elastomer in the acrylic resin layer or by forming a multilayer body of an acrylic resin layer and a polycarbonate resin layer. In this embodiment, the breaking elongation is measured by the method described in the Examples. The multilayer body of this embodiment also preferably has a small difference in breaking elongation between MD (machine direction) and TD (transverse direction). This small difference in breaking elongation between MD and TD tends to further improve the formability of the multilayer body. Specifically, the difference in breaking elongation between MD and TD is preferably 60% or less, more preferably 50% or less, even more preferably 40% or less, even more preferably 30% or less, and even more preferably 20% or less.

[0059] The thickness (total thickness) of the multilayer body is not particularly limited, but is preferably 30 μm or more, more preferably 100 μm or more. The thickness of the multilayer body is preferably 10,000 μm or less, more preferably 5,000 μm or less, and even more preferably 2,000 μm or less, and may be 1,000 μm or less, or 500 μm or less.

[0060] <Other layers> The multilayer body of this embodiment may further include a hard coat layer. The hard coat layer is preferably provided on at least one surface of the multilayer body. The hard coat layer may be the outermost layer of the multilayer body. By providing a hard coat layer, the surface hardness of the multilayer body tends to be further improved. The hard coat layer is preferably formed by laminating a polycarbonate resin layer, an acrylic resin layer, and a hard coat layer in this order. 1 is a schematic diagram showing an example of the multilayer body of this embodiment, and as described above, 1 indicates the multilayer body, 2 indicates the polycarbonate resin layer, 3 indicates the acrylic resin layer, and 4 indicates the hard coat layer. The polycarbonate resin layer 2, the acrylic resin layer 3, and the hard coat layer 4 may have other layers as long as they are laminated in the above order without departing from the spirit of this embodiment, but it is preferable that they do not have other layers, i.e., they are adjacent to each other. The other layer is preferably not a polarizer (also called a polarizing film). The other layer is preferably not a polyester resin layer. That is, the multilayer body of the present embodiment preferably does not have a polarizer and / or a polyester resin layer.Furthermore, the multilayer body of the present embodiment preferably is not used in applications in which it is laminated together with a polarizer and / or a polyester resin layer.

[0061] The hard coat layer that may be included in the multilayer body of the present embodiment is preferably a layer having a surface hardness higher than that of the polycarbonate resin layer. By including such a hard coat layer, the surface hardness of the multilayer body or molded article can be further increased. The thickness of the hard coat layer is preferably 0.5 μm or more, more preferably 1 μm or more, even more preferably 2 μm or more, and even more preferably 3 μm or more. By making the thickness equal to or greater than the lower limit, the pencil hardness of the entire multilayer body due to the hard coat layer tends to be further improved. The upper limit of the thickness of the hard coat layer is preferably 20 μm or less, more preferably 15 μm or less, even more preferably 12 μm or less, even more preferably 10 μm or less, even more preferably 8 μm or less, and may be 5 μm or less.

[0062] The hard coat layer is preferably obtained by applying a hard coat material that can be cured by heat or active energy rays, and then curing it before molding (preferably before thermoforming) and / or after molding (preferably after thermoforming). Examples of coating materials that can be cured using active energy rays include resin compositions composed of one or more monofunctional or polyfunctional (preferably di- to deca-functional) (meth)acrylate monomers or oligomers, and preferably resin compositions containing monofunctional or polyfunctional (preferably di- to deca-functional) urethane (meth)acrylate oligomers. These resin compositions preferably contain a photopolymerization initiator as a curing catalyst. Examples of thermosetting resin coatings include polyorganosiloxane-based and crosslinked acrylic-based coatings. Some of these resin compositions are commercially available as hard coating agents for acrylic or polycarbonate resin films or sheets, and an appropriate coating material may be selected taking into consideration suitability for the coating line. For the hard coat layer, the descriptions in paragraphs 0045 to 0055 of JP 2013-020130 A, paragraphs 0073 to 0076 of JP 2018-103518 A, and paragraphs 0062 to 0082 of JP 2017-213771 A can be referred to, the contents of which are incorporated herein by reference.

[0063] The multilayer body of the present embodiment may have other layers in addition to those described above, such as an adhesive layer, a pressure-sensitive adhesive layer, an antifouling layer, and the like.

[0064] The multilayer body may be subjected to one or more of anti-fingerprint treatment, anti-glare treatment, weather resistance treatment, antistatic treatment, anti-fouling treatment, and anti-blocking treatment on at least one surface thereof. An example of the outermost surface of the multilayer body in this case is a hard coat layer. The anti-blocking treatment refers to a treatment that allows films to be easily peeled even when they are in close contact with each other, and examples of such treatment include adding an anti-blocking agent and providing irregularities on the surface of the multilayer body.

[0065] <Method of manufacturing a multilayer body> The multilayer body of the present embodiment can be formed by using a main extruder that extrudes the polycarbonate resin layer-forming composition and a sub-extruder that extrudes the acrylic resin layer-forming composition, melting the resins under the conditions of the resins used, introducing them into an extrusion die, laminating them inside the die and forming them into a sheet, or by forming them into a sheet and then laminating them.

[0066] The multilayer body of the present embodiment may be used as it is, but can also be processed, particularly by heat processing, to form a heat-molded body. Furthermore, it can also be heat-bent to form a heat-molded body. An example of heat molding is film insert molding.

[0067] <Application> The multilayer body or molded body of this embodiment can be suitably used for optical parts, decorative products, anti-reflection molded bodies, and the like. The multilayer body of this embodiment is suitable for use in components for display devices, electrical and electronic devices, office automation equipment, portable information terminals, machine parts, home appliances, vehicle parts, various containers, lighting equipment, etc. Among these, it is particularly suitable for use in housings for various displays, electrical and electronic devices, office automation equipment, portable information terminals and home appliances, lighting equipment and vehicle parts (particularly vehicle interior parts), surface films for smartphones and touch panels, etc., optical materials, and optical discs. The multilayer body of this embodiment is preferably not a retardation film. [Example]

[0068] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be performed using other instruments with equivalent performance.

[0069] 1.Raw materials <Polycarbonate resin> PC-1500S: Mitsubishi Gas Chemical Company, Inc., bisphenol A (BPA) polycarbonate resin, glass transition temperature: 150°C T-1380: Mitsubishi Gas Chemical Company, Inc., bisphenol A (BPA) polycarbonate resin using parahydroxybenzoic acid hexadecyl ester (p-HBAHE) as the end-capping agent, viscosity average molecular weight: 25,500, glass transition temperature: 126°C

[0070] <Acrylic resin> 80HD: PMMA, manufactured by Asahi Kasei Corporation, polymethyl methacrylate, weight average molecular weight 114,000, glass transition temperature 105°C LP-1: Manufacturer: PMMA, manufactured by Asahi Kasei Corporation, polymethyl methacrylate, weight average molecular weight 175,000, glass transition temperature 105°C

[0071] <Elastomer> M65ST: Acrylic block copolymer, manufactured by ARKEMA, Nanostrength (registered trademark) XCT-A1095: Thermoplastic polyurethane, manufactured by Mitsui Chemicals, Inc., FORTIMO (registered trademark) W-377: Acrylic rubber particles, manufactured by Mitsubishi Chemical Corporation, Metablen (registered trademark) SR8501: PMMA with acrylic rubber, manufactured by Asahi Kasei, Delpet (registered trademark)

[0072] 2. Examples 1 to 7 and Comparative Examples 1 to 4 <Manufacturing of multilayer bodies> Multilayer bodies were molded using a multilayer extrusion device equipped with a single-screw extruder with a 32 mm shaft diameter, a single-screw extruder with a 65 mm shaft diameter, a feed block connected to all extruders, and a 650 mm-wide T-die connected to the feed block. The resin composition (pellets) used to form the acrylic resin layer in each Example and Comparative Example listed in Table 1 or Table 2 was continuously introduced into the single-screw extruder with a 32 mm shaft diameter at a cylinder temperature of 240°C and extruded. The resin composition (pellets) used to form the polycarbonate resin layer in each Example and Comparative Example listed in Table 1 or Table 2 was continuously introduced into the single-screw extruder with a 65 mm shaft diameter at a cylinder temperature of 280°C and extruded. The feed block connected to all extruders was equipped with two-type, two-layer distributor pins, and extruded and laminated. The extruded material was extruded into a sheet form through a T-die connected to the extruder, and cooled while transferring a mirror finish using three mirror-finish rolls heated to 100°C, 100°C, and 125°C from the upstream side, to obtain each multilayer body.

[0073] <Pencil hardness> The pencil hardness of the acrylic resin layer side of the multilayer body prepared above was measured using a pencil hardness tester under a load of 750 g in accordance with JIS K5600-5-4:1999. Evaluation was carried out by five experts, and judged by majority vote.

[0074] <Haze> The haze (unit: %) of the obtained multilayer body was measured under the conditions of a D65 light source and a 10° visual field. For the measurement, a haze meter ("HM-150" manufactured by Murakami Color Research Laboratory Co., Ltd.) was used.

[0075] <Elongation at break> The resulting multilayer body was subjected to a tensile test in accordance with JIS K-7127, with a tensile speed of 10 mm / min and a chuck distance of 115 mm, and the elongation (%) was measured on the stress-strain curve obtained from the tensile test. When conducting a tensile test in the machine direction (MD) of the film, the MD of the film was the measurement direction of the test piece, and when conducting a tensile test in the cross direction (TD) of the film, the TD of the film was the measurement direction of the test piece. A bench-top precision universal testing machine (Shimadzu Corporation: Autograph AGS-X, 10 kN load cell) was used as the tensile tester.

[0076] <Moldability> The obtained multilayer body was preheated at 190°C for about 40 seconds, and immediately thereafter, shaped using compressed air at 1.5 MPa. For the compressed air molding, a rectangular mold measuring 60 mm in length and 150 mm in width was used, with a radius R of 2 mm and a height of 10 mm in the area in contact with the rectangular part of the mold. The shaped laminate was placed on the cavity surface of an injection mold with a radius R of 0.5 mm in the area in contact with the right-angled portion, and a molten thermoplastic resin was injected to produce a film insert molded product. Polycarbonate resin (Iupilon H-3000, manufactured by Mitsubishi Engineering Plastics Corporation) was used as the injected resin. The mold temperature was set to 50°C, and the injection speed was set to 100 m / s. The laminate of the obtained molded product was checked for the presence or absence of cracks. The check was performed by five experts, and the judgment was made by majority vote. A: No cracks were observed. B: A very small number of tiny cracks were observed. C: Minor cracks occurred. D: Numerous cracks occurred.

[0077] <Stress whitening> The multilayer molded articles obtained in the above <Moldability> section were visually inspected for the presence or absence of whitening by five experts, who made a majority decision. A: No bleaching was observed. B: Very slight whitening. C: Clearly bleached.

[0078] [Table 1]

[0079] [Table 2]

[0080] The proportions of each component in Tables 1 and 2 above are in parts by mass. The room temperature in Tables 1 and 2 above is 23°C. As is clear from the above results, the multilayer bodies of the present invention had high elongation at break and were able to effectively suppress whitening (Examples 1 to 7). In contrast, when no elastomer was included (Comparative Example 1), the elongation at break was significantly lower. Furthermore, even when an elastomer was included, if the blending amount was large or an elastomer with a large dispersion diameter was used, the haze increased and whitening could not be suppressed (Comparative Examples 2 to 4). Furthermore, even when an elastomer was contained, the elongation at break was significantly low when it was not laminated with a polycarbonate resin layer (Reference Examples 1 and 2).

[0081] Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various modifications can be made without departing from the spirit and scope of the invention. [Explanation of symbols]

[0082] 1 Multilayer body 2 Polycarbonate resin layer 3 Acrylic resin layer 4 Hard Coat Layer

Claims

1. A multilayer body comprising an acrylic resin layer containing a (meth)acrylic resin and a polycarbonate resin layer containing a polycarbonate resin, the acrylic resin layer contains 1 to 50% by mass of an elastomer, the haze of the multilayer body is 3% or less; The thickness of the acrylic resin layer is 20 to 80 μm, A multilayer body satisfying formula (1) when the thickness of the polycarbonate resin layer is PCt and the thickness of the acrylic resin layer is Act. Formula (1): 0.1≦Act / PCt≦0.8

2. The multilayer body according to claim 1 , wherein the acrylic resin layer has a pencil hardness of F or more.

3. 3. The multilayer body according to claim 1, wherein the haze of the multilayer body is 2% or less.

4. 3. The multilayer body according to claim 1, wherein the elastomer comprises a block copolymer having hard segments and soft segments.

5. The multilayer body according to claim 1 or 2, wherein the elastomer comprises an acrylic block copolymer and / or a thermoplastic polyurethane elastomer.

6. 3. The multilayer body according to claim 1, wherein the multilayer body has a breaking elongation at 23°C of 15% or more.

7. The multilayer body according to claim 1 or 2, which does not have a polarizer and / or a polyester resin layer.

8. The acrylic resin layer has a pencil hardness of F or more, the haze of the multilayer body is 2% or less; the elastomer comprises a block copolymer having a hard segment and a soft segment, 2. The multilayer body according to claim 1, wherein the multilayer body has a breaking elongation at 23°C of 15% or more.

9. A heat-molded product obtained by heat-processing the multilayer product according to claim 1, 2 or 8.

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