laminate

Abstract

Provided is a laminate containing a polylactic acid polymer, which is excellent in durability and elongation properties. The laminate includes a first resin layer and a second resin layer. The first resin layer contains a polylactic acid polymer, a (meth)acrylic block copolymer, and a plasticizer. A content of the plasticizer is about 1 mass% or more and less than about 10 mass%. The second resin layer contains at least one selected from the group consisting of a (meth)acrylic resin, a resin having a urethane bond, and a vinyl chloride-vinyl acetate copolymer resin. The laminate has a portion to which the first resin layer and the second resin layer are directly applied.

Description

LAMINATETechnical Field

[0001] The present disclosure relates to a laminate containing a polylactic acid polymer.Background Art

[0002] In recent years, various laminates containing a polylactic acid polymer have been developed.

[0003] Patent Document 1 (JP 2019-513092 A) discloses a film containing: a semi-crystalline polylactic acid polymer; a polyvinyl acetate polymer having a Tg of at least 25 °C; and a plasticizer, in which the film having a structured surface, the structured surface including a base film layer and a structure disposed on a main surface of the base film layer.

[0004] Patent Document 2 (JP 2023-539733 A) discloses a film including a base material containing: polylactic acid, a primer layer disposed on the base material; a barrier layer disposed on a surface of the primer layer opposite to the base material; and an adhesive layer disposed on a surface of the barrier layer opposite to the primer layer, in which the barrier layer contains polyamide, and the polyamide is amorphous aliphatic polyamide and has a glass transition temperature of at least 40°C.

[0005] Patent Document 3 (JP 2019-528327 A) discloses an article that is a graphic film including a first film layer, the film layer containing: a semi-crystalline polylactic acid polymer; a polyvinyl acetate polymer having a Tg of at least 25 °C; and a plasticizer, in which a graphic is disposed on a main surface of the first film layer.Citation ListPatent Documents

[0006] Patent Document 1: JP 2019-513092 APatent Document 2: JP 2023-539733 APatent Document 3: JP 2019-528327 ASummary of InventionTechnical Problem

[0007] Polylactic acid polymers are typically hard resins and are biodegradable resins, and thus are poor in durability and elongation properties as compared with polyvinyl chloride resins or the like. Therefore, there has been desired a laminate containing a polylactic acid polymer, which is excellent in durability and elongation properties.

[0008] The present disclosure provides a laminate containing a polylactic acid polymer, which is excellent in durability and elongation properties.Solution to Problem

[0009] According to an embodiment of the present disclosure, there is provided a laminate including a first resin layer and a second resin layer, in which the first resin layer includes a polylactic acid polymer, a (meth)acrylic block copolymer, and a plasticizer, a content of the plasticizer is about 1 mass% or more and less than about 10 mass%, and the second resin layer contains at least one selected from the group consisting of a (meth)acrylic resin, a resin having a urethane bond, and a vinyl chloride-vinyl acetate copolymer resin, and the laminate has a portion to which the first resin layer and the second resin layer are directly applied.Advantageous Effects of Invention

[0010] According to the present disclosure, there can be provided a laminate containing a polylactic acid polymer, which is excellent in durability and elongation properties.

[0011] The foregoing description shall not be construed as a disclosure of all embodiments of the present invention and of all advantages related to the present invention.Brief Description of Drawings

[0012] FIG. 1 is a view schematically illustrating a cross section of a laminate according to an embodiment of the present disclosure.FIG. 2 is a view schematically illustrating a cross section of a laminate according to another embodiment of the present disclosure.FIG. 3 is a view schematically illustrating a cross section of a laminate according to another embodiment of the present disclosure.FIG. 4(a) is a photograph of a laminate of Comparative Example 4 after a durability test described later, and FIG. 4(b) is a photograph of a laminate of Example 2 after a durability test described later.Description of Embodiments

[0013] Hereinafter, typical embodiments of the present invention will be described in more detail for the purpose of illustration, but the present invention is not limited to these embodiments.

[0014] In the present disclosure, a word “on” as in a wording “an adhesive layer disposed on a release liner”, for example, means that the adhesive layer is disposed directly above the release liner, or that the adhesive layer is disposed indirectly above the release liner with another layer interposed therebetween.

[0015] In the present disclosure, a word “under” as in a wording “a release liner disposed under an adhesive layer”, for example, means that the release liner is disposed directly below the adhesive layer, or that the release liner is disposed indirectly below the adhesive layer with another layer interposed therebetween.

[0016] In the present disclosure, the term “transparent” refers to that an average transmittance in a visible light region (wavelength of from 400 nm to 700 nm) measured in accordance with JIS K 7375 is about 80% or higher, and the average transmittance may be desirably about 85% or higher, or about 90% or higher. The upper limit of the average transmittance is not particularly limited, but can be, for example, less than about 100%, about 99% or less, or about 98% or less.

[0017] In the present disclosure, the term “translucent” refers to that an average transmittance in a visible light region (wavelength of from 400 nm to 700 nm) measured in accordance with JIS K 7375 is about less than 80%, and the average transmittance may be desirably about 75% or less, and “translucent” is intended to mean that a substrate or the like is not completely hidden.

[0018] In the present disclosure, the term "film" also includes a member called a "sheet".

[0019] In the present disclosure, the term "(meth)acrylic" refers to acrylic or methacrylic, and the term "(meth)acrylate" refers to acrylate or methacrylate.

[0020] Hereinafter, a laminate of the present disclosure will be described with reference to the drawings, as necessary.

[0021] A laminate 100 in FIG. 1 includes a first resin layer 101 and a second resin layer 102, a laminate 200 in FIG. 2 includes a first resin layer 201, a second resin layer 202, and a third resin layer 203, and a laminate 300 in FIG. 3 includes a first resin layer 301, a second resin layer 302, and a third resin layer 303. Here, the third resin layer is an optional component, and the laminate of the present disclosure may include, or does not need to include the third resin layer.

[0022] Hereinafter, for the purpose of illustrating typical embodiments of the present disclosure, details of each component will be described with some reference numerals omitted.

[0023] A laminate according to an embodiment of the present disclosure includes a first resin layer and a second resin layer, and has a portion to which the first resin layer and the second resin layer are directly applied. In addition, the laminate of the present disclosure may include an optional layer (e.g., a third resin layer, a decorative layer, and a release liner) described later.

[0024] The laminate of the present disclosure includes a first resin layer containing: a polylactic acid polymer; a (meth)acrylic block copolymer; and a plasticizer. The first resin layer contains the (meth)acrylic block copolymer together with the polylactic acid polymer and contains the plasticizer in an amount of about 1 mass% or more and less than about 10 mass%, and hence can enhance the durability (e.g., crack resistance) and the elongation properties of the laminate containing the polylactic acid polymer. Since the (meth)acrylic block copolymer is a resin excellent in durability as compared with the polylactic acid polymer, the blending of the (meth)acrylic block copolymer can improve the durability of the first resin layer. The (meth)acrylic block copolymer is a resin more flexible as compared with the polylactic acid polymer, but the first resin layer of the present disclosure contains a predetermined amount of the plasticizer in addition to the (meth)acrylic block copolymer, and therefore the elongation properties can be further improved. Notwithstanding the usage of the plasticizer is relatively low, the first resin layer of the present disclosure exhibits excellent elongation properties, andcan also reduce or suppress deterioration of durability and elongation properties due to deterioration of the plasticizer associated with long-term use.

[0025] In some embodiments, a laminate including the first resin layer of the present disclosure exhibits appropriate flexibility, and hence, for example, when the laminate is formed into a film form, wrinkles of the film can be reduced or suppressed, and as a result, handleability (workability) can be improved.

[0026] The first resin layer containing the (meth)acrylic block copolymer can improve adhesiveness to a second resin layer described later, and as a result, the dimensional stability (deformation resistance) of the laminate is improved, and its durability performance (e.g., crack resistance) can be further improved as compared with a laminate not containing such second resin layer.

[0027] The polylactic acid polymer is a kind of aliphatic polyester, and can be produced, for example, by dehydration condensation between two molecules of lactic acid, ring-opening polymerization of lactide which is a cyclized product, or direct polymerization of lactic acid. Lactic acid has two optical isomers of L-lactic acid (also known as (S)-lactic acid) and D-lactic acid (also known as (R) -lactic acid). Lactic acid is a renewable material obtained by bacterial fermentation of com starch or cane sugar and can therefore be said to be a natural material, in other words a "biomass" material. The polylactic acid polymer (referred to as a "PLA polymer" in some cases) can be used singly, or two or more kinds thereof may be used in combination.

[0028] The crystallinity of the polylactic acid polymer may be mainly regulated, for example, by the ratio of D and / or meso-lactide to the L-cyclic lactide monomer used. Similarly, for polymers prepared by direct polyesterification of lactic acid, the crystallinity may be mainly regulated by the ratio of polymerization units derived from D-lactic acid to polymerization units derived from L-lactic acid.

[0029] The content of the polylactic acid polymer can be, for example, about 20 mass% or more, about 22 mass% or more, about 25 mass% or more, about 30 mass% or more, about 32 mass% or more, or about 35 mass% or more, and can be about 70 mass% or less, about 65 mass% or less, about 60 mass% or less, about 58 mass% or less, or about 55 mass% or less with respect to the total amount of the first resin layer.

[0030] In some embodiments, the first resin layer of the laminate of the present disclosure contains, as the polylactic acid polymer, at least one selected from the group consisting of a semi-crystalline polylactic acid polymer and an amorphous polylactic acid polymer. For example, when the laminate of the present disclosure is used as a decorative film or the like, the amorphous polylactic acid polymer is preferably used in terms of moldability, elongation properties, workability, and the like. As the polylactic acid polymer, a mixed resin of the semi-crystalline polylactic acid polymer and the amorphous polylactic acid polymer can be used, or the amorphous polylactic acid polymer can be used singly. In the case of considering heat resistance besides the performance mentioned above, the mixed resin of the semicrystalline poly lactic acid polymer and the amorphous poly lactic acid polymer is preferably used. In the present disclosure, the term "semi-crystalline polylactic acid polymer" is intended to mean a polylactic acid polymer in which a crystallized region and a non-crystalline (amorphous) region are mixed.

[0031] In some embodiments, the semi -crystalline PLA polymer typically contains L-lactic acid derived polymerization units (e.g. L-lactide) in an amount of 90 mass% or more, about 91 mass% or more, about 92 mass% or more, about 93 mass% or more, about 94 mass% or more, or about 95 mass% or more, and D-lactic acid derived polymerization units (e.g. D-lactide and / or meso-lactide) in an amount of about 10 mass% or less, about 9 mass% or less, about 8 mass% or less, about 7 mass% or less, about 6 mass% or less, or about 5 mass% or less. In other embodiments, the semi-crystalline PLA polymer contains L-lactic acid-derived polymerization units (e.g., L-lactide) in an amount of at least about 96 mass% and D-lactic acid-derived polymerization units (e.g., D-lactide and / or meso-lactide) in an amount of about 4 mass% or less, about 3 mass% or less, or 2 mass% or less. The first resin layer may contain an even lower concentration of D-lactic acid derived polymerization units (e.g., D-lactide and / or meso-lactide), depending on the concentration of the semi-crystalline PLA polymer in the first resin layer. For example, when the first resin layer contains about 15 mass% of semi -crystalline PLA including about 2 mass% of D-lactide and / or meso-lactide, the first resin layer can contain about 0.3 mass% of D-lactide and / or meso-lactide. The first resin layer may contain D-lactic acid derived polymerization units (e.g., D-lactide and / or meso-lactide) in an amount, for example, about 9 mass% or less, about 8 mass% or less, about 7 mass% or less, about 6 mass% or less, about 5 mass% or less, about 4 mass% or less, about 3 mass% or less, about 2 mass% or less, about 1.5 mass% or less, about 1.0 mass% or less, about 0.5 mass% or less, about 0.4 mass% or less, about 0.3 mass% or less, about 0.2 mass% or less, or about 0.1 mass% or less. Preferred examples of semi-crystalline PLA include Ingeo (trade name) 4042D and 4032D, each a product from NatureWorks (trade name). References describe that these polymers have a weight-average molecular weight (Mw) of about 200000 g / mol, a number average molecular weight (Mn) of about 100000 g / mol, and a polydispersity of about 2.0.

[0032] In some embodiments, the semi-crystalline PLA polymer contains D-lactic acid derived polymerization units (e.g., D-lactide) in an amount of, for example, about 90 mass% or more, about 91 mass% or more, about 92 mass% or more, about 93 mass% or more, about 94 mass% or more, or about 95 mass% or more, and L-lactic acid derived polymerization units (e.g., L-lactide and / or meso-lactide) in an amount of about 10 mass% or less, about 9 mass% or less, about 8 mass% or less, about 7 mass% or less, about 6 mass% or less, or about 5 mass% or less. In other embodiments, the semi-crystalline PLA polymer may contain D-lactic acid derived polymerization units (e.g., D-lactide) in an amount of about 96 mass% or more, and L-lactic acid derived polymerization units (e.g., L-lactide and / or mesolactide) in an amount of about 4 mass% or less, about 3 mass% or less, or about 2 mass% or less. The first resin layer may contain an even lower concentration of L-lactic acid derived polymerization units (e.g., L-lactide and / or meso-lactide), depending on the concentration of the semi-crystalline PLA polymer in the first resin layer. For example, when the first resin layer contains about 15 mass% of semi-crystalline PLA having about 2 mass% of L-lactide and / or meso-lactide, the first resin layer can contain about 0.3 mass% of L-lactide and / or meso-lactide. The first resin layer can contain L-lactic acid derived polymerization units (e.g., L-lactide and / or meso-lactide) in an amount of about 9 mass% or less, about 8 mass% or less, about 7 mass% or less, about 6 mass% or less, about 5 mass% or less,about 4 mass% or less, about 3 mass% or less, about 2 mass% or less, about 1.5 mass% or less, about 1.0 mass% or less, about 0.5 mass% or less, about 0.4 mass% or less, about 0.3 mass% or less, about 0.2 mass% or less, or about 0.1 mass% or less. An example of such semi-crystalline PLA is available as "Synterra (trade name) PDLA".

[0033] In some embodiments, the content of the semi-crystalline polylactic acid polymer can be about 50 mass% or less, about 45 mass% or less, about 40 mass% or less, about 35 mass% or less, about 30 mass% or less, or about 25 mass% or less, and can be about 0 mass% or more, more than about 0 mass%, about 2 mass% or more, about 5 mass% or more, or about 10 mass% or more, with respect to the total amount of the polylactic acid polymer.

[0034] In some embodiments, the first resin layer contains an amorphous polylactic acid polymer. In some embodiments, the amorphous PLA typically contains L-lactic acid derived polymerization units in an amount of about 90 mass% or less and D-lactic acid derived polymerization units (e.g., D-lactic acid lactide and / or meso-lactide) in an amount of about 10 mass% or more. In some embodiments, the amorphous PLA contains L-lactic acid derived polymerization units (e.g., L-lactide) in an amount of about 80 mass% or more or about 85 mass% or more. In some embodiments, the amorphous PLA contains D-lactic acid derived polymerization units (e.g., D-lactide and / or mesolactide) in an amount of about 20 mass% or less or about 15 mass% or less. Suitable amorphous PLAs include Ingeo (trade name) 4060D grade, a product from NatureWorks (trade name). References describe that this polymer has a weight-average molecular weight (Mw) of about 180000 g / mol.

[0035] Alternatively, the amorphous PLA typically contains D-lactic acid derived polymerization units in an amount of about 90 mass% or less, and L-lactic acid derived polymerization units (e.g., L-lactic acid lactide and / or meso-lactide) in an amount of more than about 10 mass%. In some embodiments, the amorphous PLA contains D-lactic acid derived polymerization units (e.g., D-lactide) in an amount of about 80 mass% or more or about 85 mass% or more. In some embodiments, the amorphous PLA contains L-lactic acid derived polymerization units (e.g., L-lactide and / or mesolactide) in an amount of about 20 mass% or less or about 15 mass% or less.

[0036] In some embodiments, the content of the amorphous polylactic acid polymer is about 50 mass% or more with respect to the total amount of the polylactic acid polymer. The content of the amorphous polylactic acid polymer can be about 60 mass% or more, about 65 mass% or more, about 70 mass% or more, or about 75 mass% or more, and can be about 100 mass% or less, less than about 100 mass%, about 98 mass% or less, about 95 mass% or less, or about 90 mass% or less with respect to the total amount of the polylactic acid polymer. The first resin layer containing the amorphous polylactic acid polymer at such proportion is excellent in performance such as elongation properties, and hence can improve performance such as moldability of a laminate including the first resin layer.

[0037] In some embodiments, the first resin layer of the present disclosure can contain the amorphous polylactic acid polymer in an amount of about 20 mass% or more, about 23 mass% or more, about 25 mass% or more, about 28 mass% or more, or about 30 mass% or more, and about 70 mass% or less, about 65 mass% or less, about 60 mass% or less, about 55 mass% or less, or about 50 mass% orless, based on the total amount of the polylactic acid polymer, the (meth)acrylic block copolymer, and the plasticizer. The first resin layer containing the amorphous polylactic acid polymer at such proportion is excellent in performance such as elongation properties, and hence can improve performance such as moldability of a laminate including the first resin layer.

[0038] In some embodiments, the semi-crystalline PLA polymer and the amorphous PLA polymer both generally contain a low concentration of D-lactic acid derived polymerization units (e.g., D-lactide), together with a high concentration of L-lactic acid derived polymerization units (e.g., L-lactide).

[0039] In other embodiments, the semi -crystalline PLA polymer and the amorphous PLA polymer both generally contain a low concentration of L-lactic acid derived polymerization units (e.g., L-lactide), together with a high concentration of D-lactic acid derived polymerization units (e.g., D-lactide).

[0040] The PLA polymer is preferably a "film grade" polymer having a melt flow rate of about 25 g / min or less, about 20 g / min or less, about 15 g / min or less, or about 10 g / min or less (measured according to ASTM D1238) at 210°C and a load of mass 2.16 kg. In some embodiments, the PLA polymer has a melt flow rate of about 10 g / min or less or about 9 g / min or less at 210°C. The melt flow rate is related to the molecular weight of the PLA polymer. In some embodiments, the PLA polymer has a weight-average molecular weight (Mw) of about 50000 g / mol or more, about 75000 g / mol or more, about 100000 g / mol or more, about 125000 g / mol or more, or about 150000 g / mol or more, as measured by gel permeation chromatography using a polystyrene standard material. In some embodiments, the weightaverage molecular weight (Mw) is about 400000 g / mol or less, about 350000 g / mol or less, or about 300000 g / mol or less.

[0041] In some embodiments, the PLA polymer has a tensile strength within a range of from about 25 to 150 MPa, a tensile modulus of elasticity within a range of from about 1000 to 7500 MPa, and a tensile elongation within a range of about 3% or more, about 4% or more, or about 5% or more, and about 15% or less, or about 10% or less. In some embodiments, the tensile strength at break of the PLA polymer is about 30 MPa or more, about 35 MPa or more, about 40 MPa or more, about 45 MPa or more, or about 50 MPa or more. In some embodiments, the tensile strength of the PLA polymer is about 125 MPa or less, about 100 MPa or less, or about 75 MPa or less. In some embodiments, the tensile modulus of elasticity of the PLA polymer is about 1500 MPa or more, about 2000 MPa or more, about 2500 MPa or more, or about 3000 MPa or more. In some embodiments, the tensile modulus of elasticity of the PLA polymer is about 7000 MPa or less, about 6500 MPa or less, about 6000 MPa or less, about 5500 MPa or less, about 5000 MPa or less, or about 4000 MPa or less. Such tensile and elongation properties can be measured by ASTM D882 and are typically reported from manufacturers or suppliers of such PLA polymers.

[0042] In some embodiments, the PLA polymer has a glass transition temperature (Tg) within a range of from about 50°C to about 65°C. In some embodiments, the Tg is about 51°C or higher, about 52°C or higher, about 53°C or higher, about 54°C or higher, or about 55°C or higher. The Tg of the PLA polymer can be determined by differential scanning calorimetry (DSC).

[0043] In some embodiments, the semi-crystalline PLA polymer has a (e.g., peak) melting point within a range of about 140°C or higher, and about 175°C or lower, about 180°C or lower, about 185°C or lower, or about 190°C or lower. In some embodiments, the (e.g., peak) melting point is about 145°C or higher, about 150°C or higher, or about 155°C or higher. The PLA polymer containing the semicrystalline PLA singly, or containing the semi-crystalline PLA in combination with the amorphous PLA polymer, can be melt processed at a temperature of about 180°C, about 190°C, about 200°C, about 210°C, about 220°C, or about 230°C.

[0044] In one embodiment, the PLA polymer can crystallize to form a stereocomplex (Macromolecules, 1987,20 (4), pp.904-906). The PLA stereocomplex may be formed by blending PLLA (a PLA homopolymer polymerized mainly from L-lactic acid or L-lactide units) with PDLA (a PLA homopolymer polymerized mainly from D-lactic acid or D-lactide units).

[0045] The (meth)acrylic block copolymer can be form of, for example, a polymer block (1) having a low glass transition temperature and polymer blocks (2a) and (2b) having a high glass transition temperature formed at both ends of the polymer block (1). The polymer block (1) may also be referred to as a soft segment, and the polymer blocks (2a) and (2b) each may also be referred to as a hard segment. In some embodiments, in terms of durability (crack resistance etc.), elongation properties and the like, as the (meth)acrylic block copolymer is preferably used a block copolymer having the polymer block (1) that is the soft segment. The (meth)acrylic block copolymer can be used singly, or two or more types thereof may be used in combination.

[0046] The polymer block (1) needs to be formed of a soft acrylic polymer having a low glass transition temperature (about 25°C or lower), and may be formed of, for example, a structural unit derived from an acrylic ester. Examples of the acrylic ester include an alkyl acrylate ester, an aryl acrylate ester, and an ester of acrylic acid and an alcohol containing a functional group having an etheric oxygen. These acrylic esters can be used singly, or two or more types thereof may be used in combination. Among these acrylic esters, an alkyl acrylate ester is preferable in terms of durability, elongation properties, and the like.

[0047] Examples of the alkyl acrylate ester include C1-12 alkyl acrylate esters such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, secbutyl acrylate, t-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, and lauryl acrylate. These alkyl acrylate esters can be used singly, or two or more types thereof may be used in combination as constituent units.

[0048] Among these alkyl acrylate esters, C2-8 alkyl acrylate esters such as ethyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate, particularly, C3-8 alkyl acrylate esters such as n-butyl acrylate are preferable in terms of durability, elongation properties, moldability, and the like.

[0049] The alkyl acrylate ester may be combined with another copolymerizable monomer to the extent that the effect of the present invention is not compromised. Examples of the other copolymerizable monomer include (meth)acrylic monomers (e.g., (meth)acrylic esters such as hydroxypropyl acrylate, butyl methacrylate, and glycidyl acrylate, (meth)acrylic acid, etc.), polymerizable nitrile compounds (e.g.,(meth)acrylonitrile etc.), unsaturated dicarboxylic acids or a derivative thereof (maleic anhydride etc.), vinyl esters (e.g., vinyl acetate, vinyl propionate, etc.), conjugated dienes (butadiene, isoprene, etc.), and olefins (e.g., ethylene, propylene, 1-butene, etc.). These copolymerizable monomers can be used singly, or two or more types thereof may be used in combination. Among these copolymerizable monomers, a (meth)acrylic acid monomer, particularly, an acrylic ester (e.g., allyl acrylate, vinyl acrylate, etc.) other than the alkyl acrylate ester described above is preferable. The proportion (mole ratio) of the alkyl acrylate ester to the copolymerizable monomer may be, for example, from about 100 / about 0 to about 80 / about 20, preferably from about 99.9 / about 0.1 to about 90 / about 10, more preferably from about 99 / about 1 to about 95 / about 5 in the alkyl acrylate ester / the copolymerizable monomer.

[0050] The polymer block (2a) and the polymer block (2b) each need to be formed of a hard methacrylic polymer having a high glass transition temperature (about 60°C or higher), and may be formed of, for example, a structural unit derived from methacrylic acid or of a methacrylic ester.Examples of the methacrylic ester include an alkyl methacrylate ester, an aryl methacrylate ester, and an ester of methacrylic acid and an alcohol containing a functional group having an etheric oxygen. These methacrylic esters can be used singly, or two or more types thereof may be used in combination. Among these methacrylic esters, alkyl esters of methacrylic acid are preferable in terms of durability and the like.

[0051] Examples of the alkyl methacrylate ester include C1-5 alkyl methacrylate esters such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, amyl methacrylate, and isoamyl methacrylate, and C5-12 cycloalkyl methacrylate esters such as cyclohexyl methacrylate. These alkyl methacrylate esters can be used singly, or two or more types thereof may be used in combination as constituent units.

[0052] Among these alkyl methacrylate esters, a C1-5 alkyl methacrylate ester is preferable, and a Ci-3 alkyl methacrylate ester (particularly methyl methacrylate) is more preferable in terms of durability, miscibility with a polylactic acid polymer, and the like.

[0053] The alkyl methacrylate ester may also be combined with another copolymerizable monomer (especially, a methacrylic monomer such as allyl methacrylate, vinyl methacrylate, or methacrylic acid) in the same manner as the alkyl acrylate ester described above to the extent that the effect of the present invention is not compromised. As for the proportion, the same proportion as that of the alkyl acrylate ester can also be employed.

[0054] The structure of the (meth)acrylic block copolymer may be, for example, a block structure in which the polymer block (2a) and the polymer block (2b) are respectively bonded to both ends of the polymer block (1), that is, a triblock structure (2a-l-2b) in which the polymer block (2a) and the polymer block (2b) are disposed at both ends of the polymer block (1) located at the center. The polymer block (2a) and the polymer block (2b) may be formed of different types of polymers (when the types and compositions of monomers as constituents of the polymer are different), but in terms of miscibility between (meth)acrylic block copolymers, the polymer blocks (2a) and (2b) are preferably formed of the same or similar polymers. Furthermore, in terms of miscibility with the polylactic acidpolymer, both the polymer block (2a) and the polymer block (2b) are more preferably formed of C1-3 alkyl methacrylate ester (particularly, methyl methacrylate) units.

[0055] In some embodiments, the glass transition temperature of the polymer block (1) can be about 25°C or lower, about 0°C or lower, or about -20°C or lower, and can be about -100°C or higher, or about -70°C or higher. In some embodiments, the glass transition temperatures of each of the polymer block (2a) and the polymer block (2b) can be about 60°C or higher, about 80°C or higher, or about 100°C or higher, and can be about 200°C or lower, or about 150°C or lower. Here, the glass transition temperature of each polymer block refers to a maximum value of a loss tangent (tan 5) obtained by a method of temperature dependence of dynamic viscoelasticity, and can be measured under the following apparatus and measurement conditions:Apparatus: Wide area dynamic viscoelasticity measuring apparatus (Forced vibration-Non-resonance method), "PVE-V4 FT-RheoSpectra" available from Rheology Co., Ltd.Measurement conditions: measurement frequency: 11 HzMeasurement mode: tensileHeating rate: 3°C / minStrain: 0.03%Sample shape: strip shape with length of 20 mm x width of 5 mm x thickness of 1 mm (press sheet)

[0056] In some embodiments, the weight-average molecular weight of the polymer block (1) (hereinafter, sometimes referred to as "Mw (1)") is greater than any of the weight-average molecular weight of the polymer block (2a) (hereinafter, sometimes referred to as "Mw (2a)") and the weightaverage molecular weight of the polymer block (2b) (hereinafter, sometimes referred to as "Mw (2b)"). For example, in terms of miscibility with the polylactic acid polymer and elongation properties, the Mw (1) of the polymer block (1) can be, for example, more than about 1 time, about 1.5 times or more, about 2 times or more, about 3 times or more, or about 4 times or more, and can be about 50 times or less, about 30 times or less, about 10 times or less, about 9 times or less, or about 8 times or less, greater than each of the Mw (2a) of the polymer block (2a) and the Mw (2b) of the polymer block (2b).

[0057] The weight-average molecular weight of the entirety of the (meth)acrylic block copolymer can be, for example, about 20000 or more, about 30000 or more, or about 50000 or more, and can be about 1000000 or less, about 500000 or less, or about 300000 or less in terms of durability, elongation properties, and the like.

[0058] The molecular weight distribution of the (meth)acrylic block copolymer, that is, the ratio (Mw / Mn) of the weight-average molecular weight (Mw) to the number average molecular weight (Mn) can be, for example, about 1.0 or more, or about 1.01 or more, and can be about 1.4 or less, about 1.3 or less, or about 1.25 or less.

[0059] The weight-average molecular weight and the number average molecular weight of the (meth)acrylic block copolymer respectively mean the weight-average molecular weight and the numberaverage molecular weight measured by a method of gel permeation chromatography in terms of polystyrene (hereinafter referred to as "GPC"), and can be measured by the following method:Apparatus: GPC apparatus "HLC-8020" available from Tosoh CorporationSeparating column: a serial connection of "TSKgel GMHXL", "G4000HXL", and "G5000HXL" available from Tosoh CorporationEluent: TetrahydrofuranEluent flow rate: 1 ml / minColumn temperature: 40°CDetection method: differential refractive index (RI)

[0060] The proportion between the polymer block (1) and the total content of the polymer block (2a) and the polymer block (2b) in the (meth)acrylic block copolymer can be appropriately set according to the intended use and the like of the laminate. For example, the proportion of the polymer block (1) can be about 25 mass% or more, about 30 mass% or more, about 40 mass% or more, about 50 mass% or more, about 60 mass% or more, or about 65 mass% or more, and can be about 90 mass% or less, about 85 mass% or less, about 80 mass% or less, about 70 mass% or less, about 65 mass% or less, or about 60 mass% or less with respect to the total mass of the (meth)acrylic block copolymer.

[0061] The melt viscosity (a melt viscosity at temperature of 200°C and shear rate of 100 sec1) of the (meth)acrylic block copolymer can be, for example, about 10 Pa • s or more, about 50 Pa • s or more, or about 100 Pa • s or more, and can be about 2000 Pa • s or less, about 1800 Pa • s or less, or about 1500 Pa • s or less.

[0062] The (meth)acrylic block copolymer can be produced by a known method, and the production method thereof is not particularly limited. As the (meth)acrylic block copolymer, a commercially available product may be used, and examples thereof include “KURARITY (trade name)” series (e.g., KURARITY (trade name) LA2250, KURARITY (trade name) LA4285, and KURARITY (trade name) LH8166) available from Kuraray Co., Ltd.

[0063] The content of the (meth)acrylic block copolymer is, for example, preferably about 10 mass% or more, about 12 mass% or more, or about 15 mass% or more, and preferably about 40 mass% or less, about 35 mass% or less, or about 30 mass% or less with respect to the total amount of the first resin layer in terms of durability (crack resistance etc.), elongation properties, moldability, and the like. When yellowing resistance is also considered, the content of the (meth)acrylic block copolymer is more preferably about 25 mass% or less, about 20 mass% or less, about 18 mass% or less, or about 15 mass% or less. The first resin layer of the present disclosure contains the (meth)acrylic block copolymer in such a proportion together with a predetermined amount of a plasticizer, and therefore can exhibits excellent durability (crack resistance etc.) and elongation properties, and can improve yellowing resistance. The content of the (meth)acrylic block copolymer is preferably about 25 mass% or less in terms of nonflammability as well.

[0064] As the plasticizer, various plasticizers capable of plasticizing PLA can be used. For example, the plasticizer is generally a liquid at 25 °C and may have a weight-average molecular weight (Mw)ranging from about 200 g / mol to about 10000 g / mol as measured by gel permeation chromatography using a polystyrene standard material. In some embodiments, the molecular weight (Mw) of the plasticizer is about 5000 g / mol or less. In other embodiments, the molecular weight of the plasticizer is about 4000 g / mol or less, about 3000 g / mol or less, about 2000 g / mol or less, or about 1000 g / mol or less. The plasticizer can be used singly, or two or more types thereof may be used in combination. Here, the "plasticizer" of the present disclosure does not include the above-mentioned (meth)acrylic block copolymer and the polyvinyl acetate polymer.

[0065] In some embodiments, the plasticizer preferably contains one or more alkyl ester groups or aliphatic ester groups or ether groups. As such plasticizer, a polyfunctional ester and / or an ether is preferable. Examples of these include alkyl phosphate esters, dialkyl ether diesters, tricarboxylate esters, epoxidized oils and esters, polyesters, polyglycol diesters, alkyl alkyl ether diesters, aliphatic diesters, alkyl ether monoesters, citrate esters, dicarboxylate esters, vegetable oils and derivatives thereof, and esters of glycerin. Such plasticizers are generally free of aromatic groups and not containing halogen atoms and are expected to be biodegradable. Such a plasticizer may further contain a linear or branched alkyl end group having a carbon chain length from C2 to Cio.

[0066] In one embodiment, the plasticizer is a biomass-derived citric acid-based plasticizer represented by Formula (I) set forth below:[Chemical Formula 1]where in the formula:R is independently an alkyl group which may be the same or different,R’ is H or a (C1-C10) acyl group.

[0067] R may independently be a linear or branched alkyl group having a carbon chain length from Ci to Cio. In some embodiments, R is a C2-C8 or C2-C4 linear alkyl group. In some embodiments, R’ is acetyl. In other embodiments, at least one R is a branched alkyl group having a carbon chain length of C5 or more. In some embodiments, the branched alkyl group has a carbon chain length of 8 or less.

[0068] Examples of typical citric acid based plasticizers include triethyl citrate, acetyl triethyl citrate, tributyl citrate, acetyl tributyl citrate, trihexyl citrate, acetyl trihexyl citrate, trioctyl citrate, acetyl trioctyl citrate, butyryl trihexyl citrate, acetyl tris-3 -methyl butyl citrate, acetyl tris-2 -methyl butyl citrate, acetyl tris-2 -ethyl hexyl citrate, and acetyl tris-2-octyl citrate. Another typical citric acidbased plasticizer is acetyl tri-n-butyl citrate available under the trade name CITROFLEX A-4 PLASTICIZER from Vertellus Specialties, Incorporated (Indianapolis, IN).

[0069] In other embodiments, the plasticizer contains a polyethylene glycol backbone and an ester alkyl end group. The weight-average molecular weight (Mw) of the polyethylene glycol moiety may be, for example, about 100 g / mol or more, about 150 g / mol or more, or about 200 g / mol or more, and about 1000 g / mol or less, as measured by gel permeation chromatography using a polystyrene standard material. In some embodiments, the polyethylene glycol moiety has a weight-average molecular weight (Mw) of about 900 g / mol or less, about 800 g / mol or less, about 700 g / mol or less, or about 600 g / mol or less. Examples of such plasticizers include polyethylene glycol (400) diethylhexanoate sold under the trade name "TegMeR (trade name) 809" from Hallstar (Chicago, IL) and tetraethylene glycol diethylhexanoate sold under the trade name "TegMeR (trade name) 804" from Hallstar (Chicago, IL).

[0070] In another embodiment, examples of the plasticizer include those commercially available as Admex (trade name) 6995 from Eastman (Kingsport, TN). Such plasticizers can be characterized as polymeric adipates (i.e., a polyester derived from adipic acid).

[0071] In another embodiment, the plasticizer is a substituted or unsubstituted aliphatic polyester, such as those described in the U.S. Patent No. 8, 158,731, which is incorporated herein by reference.

[0072] In some embodiments, the aliphatic polyester plasticizer contains repeating units that may be derived from succinic acid, glutaric acid, adipic acid, and / or sebacic acid. In some embodiments, the polyester of the polymer blend disclosed herein contains repeating units that may be derived from 1,3-propanediol and / or 1,2-propanediol. In some embodiments, the polyester of the polymer blend disclosed herein contains one or two terminator units that may be derived from 1 -octanol, 1 -decanol, and / or mixtures thereof. In some embodiments, the polyester of the polymer blend disclosed herein contains repeating units that may be derived from succinic acid, glutaric acid, adipic acid, and / or sebacic acid, repeating units that may be derived from 1,3-propanediol and / or 1,2-propanediol, and one or two terminating units that may be derived from 1 -octanol, 1 -decanol, and / or mixtures thereof.

[0073] In some embodiments, the aliphatic polyester plasticizer has Formula (II) set forth below: [Chemical Formula 2]where in the formula, n is from 1 to 1000, R1is selected from the group consisting of a covalent bond and a substituted or unsubstituted aliphatic hydrocarbon group having from 1 to 18 carbon atoms, R2is a substituted or unsubstituted aliphatic hydrocarbon group having from 1 to 20 carbon atoms, X1is selected from the group consisting of -OH, -OzC-R^COzH, and -OzC-R^COzR3, X2is selected from the group consisting of -H, -R2-OH, and R3, and R3is a substituted or unsubstituted aliphatic hydrocarbon group having from 1 to 20 carbon atoms.

[0074] In some embodiments, the polyester has Formula (II) set forth above with the proviso that, X2is R3when X1is -OH or OzC-R^COzH.

[0075] The number n of repeating units is selected such that the aliphatic polyester plasticizer has the aforementioned molecular weight.

[0076] In some embodiments, R1, R2, and / or R3is an alkyl group. The R1alkyl group may include, for example, from 1 to 18 carbon atoms, from 1 to 10 carbon atoms, from 1 to 8 carbon atoms, from 2 to 7 carbon atoms, from 2 to 6 carbon atoms, from 2 to 5 carbon atoms, from 2 to 4 carbon atoms, and / or 3 carbon atoms. For example, R1can be selected from the group consisting of -(CH2)2-, -(CFh)?-, -(CH2)4-, and -(CH2)S-. The R2alkyl group may include, for example, from 1 to 20 carbon atoms, from 1 to 10 carbon atoms, from 1 to 8 carbon atoms, from 2 to 7 carbon atoms, from 2 to 6 carbon atoms, from 2 to 5 carbon atoms, from 2 to 4 carbon atoms, and / or 3 carbon atoms. For example, R2can be selected from the group consisting of -(C ^)?-, -CFFCF^CFF)-, and -CH(CH3)CH2-. The R3alkyl group may include, for example, from 1 to 20 carbon atoms, from 1 to 18 carbon atoms, from 2 to 16 carbon atoms, from 3 to 14 carbon atoms, from 4 to 12 carbon atoms, from 6 to 12 carbon atoms, from 8 to 12 carbon atoms, and / or 8 to 10 carbon atoms. For example, R3may be a mixed type containing -(CFbkCFh and TCFELCFf.

[0077] In some embodiments, R1is an alkyl group having from 1 to 10 carbon atoms, R2is an alkyl group having from 1 to 10 carbon atoms, and R3is an alkyl group having from 1 to 20 carbon atoms. In other embodiments, R1is an alkyl group having from 2 to 6 carbon atoms, R2is an alkyl group having from 2 to 6 carbon atoms, and R3is an alkyl group having from 8 to 12 carbon atoms. In yet other embodiments, R1is an alkyl group having from 2 to 4 carbon atoms, R2is an alkyl group having from 2 to 3 carbon atoms, and R3is an alkyl group having from 8 to 10 carbon atoms. In yet other embodiments, R1is selected from the group consisting of -(C ^-, -(QL^-, -(CF^-, and -(QDs-, R2is selected from the group consisting of -(CIDs-, -CFFCF^CFF)-, and -CH(CH3)CH2-, and R3is a mixed type containing -(CFF CFF and -(CFh^CFb.

[0078] The aliphatic polyester plasticizer may have an acid value of from about 0 to about 20, or more. The acid value of the polyester can be determined by a known method that measures the number of milligrams of potassium hydroxide required to neutralize a free acid in 1 g of the polyester sample.

[0079] Plasticizers having a low acid value are typically preferred for shelflife stability and / or durability of the laminate. In some embodiments, the acid value of the plasticizer is preferably about 10 or less, about 9 or less, about 8 or less, about 7 or less, about 6 or less, about 5 or less, about 4 or less, about 3 or less, about 2 or less, or about 1 or less.

[0080] The aliphatic polyester plasticizer may have a hydroxyl value of from about 0 to about 110, for example, from about 1 to about 40, from about 10 to about 30, from about 15 to about 25, from about 30 to about 110, from about 40 to about 110, from about 50 to about 110, and / or from about 60 to about 90. The polyester may also have a hydroxyl value greater than about 110. The hydroxyl value of the polyester can be measured by a known method for measuring hydroxyl groups, such as the method described in ASTM D4274 Test Method.

[0081] One typical aliphatic polyester plasticizer is sold under the trade name HALLGREEN R-8010 (trade name) from Hallstar (Chicago, IL).

[0082] In some embodiments, the plasticizer compound typically has little or no hydroxyl groups. In some embodiments, the mass proportion mass% of the hydroxyl group to the total weight of the plasticizer compound is about 10 mass% or less, about 9 mass% or less, about 8 mass% or less, about 7 mass% or less, about 6 mass% or less, about 5 mass% or less, about 4 mass% or less, about 3 mass% or less, about 2 mass% or less, or about 1 mass% or less. In some embodiments, the plasticizer compound is free of hydroxyl groups. Thus, in the present embodiment, the plasticizer is neither glycerol nor water.

[0083] The first resin layer of the present disclosure contains the plasticizer in an amount of about 1 mass% or more and less than about 10 mass% with respect to the total amount of the first resin layer. The content of the plasticizer is preferably about 2 mass% or more, about 3 mass% or more, about 4 mass% or more, or about 5 mass% or more, and about 9 mass% or less, about 8 mass% or less, or about 7 mass% or less with respect to the total amount of the first resin layer in terms of durability (crack resistance etc.), elongation properties, moldability, and the like. The resin layer containing a plasticizer at a high concentration becomes too soft and has no firmness, and as a result, wrinkles tend to occur during handling, and defects such as poor appearance may occur. The first resin layer of the present disclosure can reduce or suppress such issues, because the blending amount of the plasticizer therein is as low as less than about 10 mass%. In some embodiments, since the first resin layer of the present disclosure contains the plasticizer at such a proportion, the above-described (meth)acrylic block copolymer can be blended at a relatively low amount of about 25 mass% or less, and as a result, there can be reduced or suppressed poor appearance such as yellowing that may occur when the (meth)acrylic block copolymer is contained at a high concentration, while excellent durability (crack resistance etc.) and elongation properties are exhibited.

[0084] In some embodiments, the content proportion of the plasticizer to the total content of the (meth)acrylic block copolymer and the plasticizer, which are components related to flexibility, in the first resin layer is about 10 mass% or more and about 50 mass% or less. Such content proportion can be about 12 mass% or more, about 13 mass% or more, about 14 mass% or more, or about 15 mass% or more, and can be about 45 mass% or less, about 43 mass% or less, or about 40 mass% or less. When the plasticizer is contained in such a proportion in the components related to flexibility, the durability and elongation properties of the laminate including the first resin layer can be further improved. In some embodiments, when the plasticizer is contained at such a proportion, there can be also reduced or suppressed poor appearance associated with yellowing and / or occurrence of wrinkles when the laminate is stuck to an adherend or the like.

[0085] The thickness of the first resin layer may be appropriately set in consideration of required performance and the like. Such a thickness can be, for example, about 1 micrometer or more, about 3 micrometers or more, about 5 micrometers or more, about 10 micrometers or more, or about 15 micrometers or more, and can be about 100 micrometers or less, or about 50 micrometers or less, about 20 micrometers or less, about 15 micrometers or less, or about 10 micrometers or less.

[0086] The first resin layer can be optionally blended with another component singly or a combination of two or more other components to the extent that the effect of the present disclosure is not adversely affected. Examples of such optional components include a conductive agent, a thermal conductivity imparting agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a dispersant, a lubricant, a surfactant, a filler, a leveling agent, a silane coupling agent, a hydrolysis inhibitor, a nucleating agent, another polymer (e.g., polyvinyl acetate), a catalyst, a pigment, and a dye.

[0087] Among such optional components, a polyvinyl acetate polymer is preferably used in terms of imparting flexibility, and an antioxidant is preferably used in terms of imparting yellowing resistance.

[0088] In some embodiments, the polyvinyl acetate polymer has a glass transition temperature (Tg) of about 25°C or higher, about 30°C or higher, about 35°C or higher, or about 40°C or higher, and about 80°C or lower, about 75°C or lower, about 70°C or lower, about 65°C or lower, about 60°C or lower, about 55°C or lower, about 50°C or lower, or about 45°C or lower. Such glass transition temperatures are values measured according to ASTM D3418-12 using a TA Instruments Differential Scanning Calorimeter unless otherwise specified.

[0089] In some embodiments, the polyvinyl acetate polymer typically has a weight-average molecular weight or a number average molecular weight (determined by size exclusion chromatography using polystyrene standard material) of about 50000 g / mol or more, about 75000 g / mol or more, about 100000 g / mol or more, about 125000 g / mol or more, about 150000 g / mol or more, about 175000 g / mol or more, about 200000 g / mol or more, about 225000 g / mol or more, or about 250000 g / mol or more. In some embodiments, the molecular weight (Mw) is about 2000000 g / mol or less, about 1500000 g / mol or less, about 1000000 g / mol or less, about 750000 g / mol or less, about 500000 g / mol or less, about 450000 g / mol or less, about 400000 g / mol or less, about 350000 g / mol or less, or about 300000 g / mol or less. In some embodiments, the molecular weight of the polyvinyl acetate polymer is greater than the molecular weight of the PLA polymer. In one embodiment, the polyvinyl acetate polymer can be characterized as having a viscosity within the range of about 10 mPa • s or more, and about 50 mPa • s or less, or about 100 mPa • s or less in a 10 mass% ethyl acetate solution at 20°C. In another embodiment, the polyvinyl acetate polymer can be characterized as having a viscosity within a range of from about 5 to about 20 mPa • s in a 5 mass% ethyl acetate solution at 20°C.

[0090] In some embodiments, the polyvinyl acetate polymer is typically a homopolymer. However, on the condition that the Tg of the polyvinyl acetate polymer is within the range set forth above, the polymer may contain a relatively low concentration of repeating units derived from another comonomer. Examples of the other comonomer include: an acrylic monomer such as acrylic acid and methyl acrylate; a vinyl monomer such as vinyl chloride and vinyl pyrrolidone; and a C2-C8 alkylene monomer such as ethylene. The total concentration of repeating units derived from the other comonomer in the polyvinyl acetate polymer is typically about 10 mass% or less, about 9 mass% or less, about 8 mass% or less, about 7 mass% or less, about 6 mass% or less, or about 5 mass% or less. In some embodiments, the concentration of repeating units derived from the other comonomer in the polyvinyl acetate polymer is typically about 4 mass% or less, about 3 mass% or less, about 2 mass% or less, about 1 mass% or less, or about 0.5 mass%or less. The polyvinyl acetate polymer is typically hydrolyzed at low levels. The polymerization units of the polyvinyl acetate polymer hydrolyzed into vinyl alcohol units are generally about 10 mol% or less, about 9 mol% or less, about 8 mol% or less, about 7 mol% or less, about 6 mol% or less, about 5 mol% or less, about 4 mol% or less, about 3 mol% or less, about 2 mol% or less, about 1 mol% or less, or about 0.5 mol% or less of the polyvinyl acetate polymer.

[0091] The polyvinyl acetate polymers are commercially available from a variety of suppliers, including under the tradename VINNAPAS (trade name) (Wacker) and the tradename VINAVIL (trade name) (Americas Corporation (West Chicago, IL)). Such polyvinyl acetate polymers, prior to combining with PLA, are often in the form of solid powders (e.g., white) or colorless beads. In some embodiments, the polyvinyl acetate polymer (e.g., powder prior to combining with the PLA polymer) is not of water redispersibility. The polyvinyl acetate polymer can be used singly, or two or more types thereof can be used in combination.

[0092] The content of the polyvinyl acetate polymer can be, for example, about 5 mass% or more, about 8 mass% or more, or about 10 mass% or more, and about 20 mass% or less, about 19 mass% or less, about 18 mass% or less, or about 17 mass% or less with respect to the total amount of the first resin layer.

[0093] The antioxidant is not particularly limited, and for example, a hindered phenolic antioxidant and a phosphorus antioxidant can be used. Examples of commercially available products of such an antioxidant include Irganox (trade name) 1010 and Irgafos (trade name) 168. The antioxidant can be used singly, or two or more types thereof can be used in combination.

[0094] The content of the antioxidant can be, for example, about 0.010 mass% or more, about 0.012 mass% or more, or about 0.015 mass% or more, and about 2.0 mass% or less, about 1.5 mass% or less, about 1.3 mass% or less, or about 1.0 mass% or less with respect to the total amount of the first resin layer.

[0095] The laminate of the present disclosure includes a second resin layer containing at least one resin selected from the group consisting of a (meth)acrylic resin, a resin having a urethane bond, and a vinyl chloride-vinyl acetate copolymer resin (sometimes referred to as "vinyl chloride -vinyl acetate resin"). Such second resin layer may be a resin layer exhibiting adhesive performance, or may be a resin layer not exhibiting adhesive performance. For example, in the configuration of FIG. 1, the second resin layer 102 can be an adhesive layer. When the second resin layer is an adhesive layer, the second resin layer can be formed using, for example, a solvent type, emulsion type, pressure-sensitive type, heat sensitive type, heat curable type, or radiation (e.g., ultraviolet ray) curable type adhesive.

[0096] The content of such resin material in the second resin layer is not particularly limited, and can be appropriately set in consideration of required performance and the like. For example, such resin material can be about 20 mass% or more, about 30 mass% or more, about 40 mass% or more, about 50 mass% or more, about 60 mass% or more, about 70 mass% or more, or about 80 mass% or more, and can be about 100 mass% or less, about 95 mass% or less, about 90 mass% or less, about 80 mass% orless, about 70 mass% or less, about 60 mass% or less, or about 50 mass% or less with respect to the entirety of the second resin layer.

[0097] Examples of the (meth)acrylic resin include acrylic polymers obtained by polymerizing or copolymerizing one type or two or more types of methacrylate monomers such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate, and acrylate monomers such as methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate. The alkyl group of these alkyl (meth) acrylates may be linear or branched. In addition, these monomers may include another monomer copolymerizable with the alkyl (meth)acrylate as long as the effects of the present invention are not compromised.

[0098] In the present disclosure, the term “resin having a urethane bond” may include, for example, a resin prepared using at least one selected from urethane (meth)acrylate and urethane (meth)acrylate oligomer, besides a urethane resin, and the urethane resin can also include a (meth)acrylic urethane resin, and the like.

[0099] The second resin layer of the present disclosure has a portion directly applied to the first resin layer described above. The portion directly applied may be the entire surface of the second resin layer or a part thereof. The second resin layer is excellent in adhesion to the first resin layer described above, and hence the laminate including these layers, according to the present disclosure, is excellent in dimensional stability (deformation resistance), and as a result, can further improve durability performance (e.g., crack resistance) as compared with a laminate not including such second resin layer.

[0100] The thickness of the second resin layer may be appropriately set in consideration of required performance and the like. Such a thickness can be, for example, about 1 micrometer or more, about 3 micrometers or more, about 5 micrometers or more, about 10 micrometers or more, or about 15 micrometers or more, and can be about 100 micrometers or less, about 50 micrometers or less, about 20 micrometers or less, about 15 micrometers or less, or about 10 micrometers or less.

[0101] The second resin layer can be optionally blended with another component singly, or a combination of two or more types of other components to the extent that the effect of the present disclosure is not adversely affected. Examples of the optional component include a conductive agent, a thermal conductivity imparting agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a dispersant, a lubricant, a surfactant, a filler, a leveling agent, a silane coupling agent, a catalyst, a pigment, and a dye.

[0102] In some embodiments, the laminate of the present disclosure optionally includes an additional layer. Examples of the additional layer include at least one selected from the group consisting of a cover layer, a decorative layer (e.g., a color layer, a pattern layer, or a relief layer), a bright layer, a bonding layer, an intermediate film layer, an adhesive layer, and a release liner. The additional layer may be applied to the entire surface of the laminate or a part thereof. The additional layer may have a three-dimensional shape on its surface, such as an embossed pattern. A laminate including a layer (e.g., a decorative layer) capable of exhibiting decorativeness may also be referred to as a "decorative laminate". When exhibiting protection performance, for example, performance capableof preventing chipping due to pebbles or the like, the laminate can also be referred to as a "protective laminate". In some embodiments, the first resin layer described above may be allowed to function as a cover layer, a decorative layer, or an intermediate film layer, and the second resin layer described above may be allowed to function as a cover layer, a decorative layer, a bonding layer, an intermediate film layer, or an adhesive layer. In the case where the first resin layer and the second resin layer function as such a layer, the following materials, thicknesses, and the like can be appropriately adopted for the first resin layer and the second resin layer to the extent that the effects of the present disclosure are not adversely affected.

[0103] The material of the cover layer is not particularly limited, and for example, a polylactic acid (PLA) resin, a (meth)acrylic resin containing polymethyl methacrylate (PMMA) and a (meth)acrylic copolymer, a resin (e.g., polyurethane) having a urethane bond, a silicone resin, polycarbonate (PC), a polyolefin such as polyethylene (PE) or polypropylene (PP), a polyester such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), a polyamide such as nylon, a copolymer such as an ethylene / acrylic acid copolymer (EAA) and its ionomer, an ethylene-ethyl acrylate copolymer, an ethylene-vinyl acetate copolymer, an ethylene -vinyl alcohol copolymer (EVOH), and the like can be used singly, or a blend of two or more types thereof can be used. The cover layer may have a multilayer structure. For example, the cover layer may have a laminated configuration of a film formed from the resin, or may be a multilayer coating of the resin. The cover layer may have a three-dimensional uneven shape such as an embossed pattern on the entirety or part of the surface thereof.

[0104] The cover layer can be formed by coating the first resin layer or the like with a resin composition directly or via a bonding layer or the like. The coating of the cover layer can be performed before application or after application of the laminate to an adherend (e.g., a support member described later). Alternatively, the cover layer may be formed by coating a release liner with a resin composition. The cover layer can be formed by, for example, coating a release liner or the like with a resin material such as a PLA resin, a curable (meth)acrylic resin composition, or a urethane composition by knife coating, bar coating, blade coating, doctor coating, roll coating, cast coating, or the like, and performing radiation (e.g., ultraviolet rays) irradiation treatment or heat treatment as necessary.

[0105] For the cover layer, there may be used a product formed into a film form in advance by extrusion, drawing, or the like. Such a film can be laminated on the first resin layer or the like via the bonding layer. When a film with high flatness is used as such a film, an appearance with higher surface flatness can be provided to an article (a structure). The cover layer can also be formed by multilayer extrusion with other layers. As the other layer, for example, a (meth)acrylic film can be used. As the (meth)acrylic film, for example, a resin containing a PLA resin, polymethyl methacrylate (PMMA), poly(butyl acrylate), a (meth)acrylic copolymer, an ethylene / acrylic copolymer, an ethylene-vinyl acetate / acrylic copolymer, or the like can be made into a film shape and used.

[0106] The cover layer of the present disclosure can contain, as an optional component, for example, a filler, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a hard coat material, a gloss imparting agent, a dispersant, a plasticizer, a flow improver, a surfactant, a levelingagent, a silane coupling agent, a catalyst, a pigment, a dye, and the like to the extent that the effect of the present disclosure is not adversely affected.

[0107] The cover layer may be overall or partially translucent or opaque. However, when the laminate includes, for example, a decorative layer or the like, the cover layer is preferably transparent in terms of visibility of such a layer or the like. The cover layer may be colored as long as the definition of "transparent" or "translucent" described above is satisfied.

[0108] The thickness of the cover layer may vary, but may be, for example, about 1 micrometer or more, about 5 micrometers or more, or about 10 micrometers or more, and may be about 200 micrometers or less, about 100 micrometers or less, or about 80 micrometers or less.

[0109] Examples of the decorative layer include, but are not limited to, a color layer that exhibits a paint color, for example, a light color, such as white and yellow, and a dark color, such as red, brown, green, blue, gray, and black; a pattern layer that imparts a design pattern (such as a wood grain, a stone grain, a geometric pattern, or a leather pattern), a logo, a pictorial pattern, or the like to an article; a relief (embossed pattern) layer having a surface provided with an uneven shape; and combinations of these layers. The decorative layer may have a single layer structure or a multilayer structure, and may be transparent, translucent, or opaque.

[0110] The decorative layer can be applied directly or via a bonding layer or the like to, but not limited to, the entire surface or part of a layer as a constituent of the laminate, such as the first resin layer and / or the second resin layer.

[0111] The material for the color layer is not limited to the following, but for example, there can be used a material in which a pigment such as an inorganic pigment (carbon black, chrome yellow, yellow iron oxide, colcothar, red iron oxide or the like) or an organic pigment (a phthalocyanine pigment such as phthalocyanine blue or phthalocyanine green, an azo lake pigment, an indigo pigment, a perinone pigment, a perylene pigment, a quinophthalone pigment, a dioxazine pigment, a quinacridone pigment such as quinacridone red, or the like) is dispersed in a binder resin such as a (meth)acrylic resin or a resin having a urethane bond.

[0112] The color layer can be formed by using such a material, and by a coating method such as gravure coating, roll coating, die coating, bar coating, or knife coating.

[0113] The pattern layer is not limited to the following, but for example, there can be adopted a layer having a pattern such as a design, a logo, or a pictorial pattern directly applied to a colored layer and / or an adhesive layer by using a printing method such as gravure direct printing, gravure offset printing, inkjet printing, laser printing, or screen printing; or there can also be used a film, a sheet, or the like having a design, a logo, a pictorial pattern, or the like formed by coating such as gravure coating, roll coating, die coating, bar coating, or knife coating, punching, etching, or the like. As the material of the pattern layer, for example, the same material as the material used in the color layer can be used.

[0114] As the relief layer, there can be used a thermoplastic resin film having a surface with uneven shape formed by a known method such as embossing, scratch processing, laser processing, dry etching,or hot pressing. A thermosetting or radiation-curable resin, such as a curable (meth)acrylic resin, is applied onto a release liner having an uneven shape, and cured by heat or radiation exposure followed by removing of the release liner and thereby enabling to form a relief layer.

[0115] The thermoplastic resin, thermosetting resin, and radiation-curable resin used in the relief layer are not particularly limited but, for example, a polyester resin such as PET or PEN, a (meth)acrylic resin, a polyolefin resin such as polyethylene or polypropylene, a thermoplastic elastomer, polycarbonate, polyamide, an ABS resin, an acrylonitrile -styrene resin, polystyrene, vinyl chloride, or a resin having a urethane bond can be used. The relief layer may contain at least one of the pigments used in the color layer.

[0116] The decorative layer of the present disclosure can contain as an optional component, for example, a filler, a reinforcing agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a dispersant, a flow improver, a surfactant, a leveling agent, a silane coupling agent, a catalyst, and the like to the extent that the effect of the present disclosure is not adversely affected.

[0117] The thickness of the decorative layer is not particularly limited as long as it is appropriately adjusted according to the required decorativeness and the like. Such a thickness can be, for example, about 1 micrometer or more, about 3 micrometers or more, or about 5 micrometers or more, and can be about 50 micrometers or less, about 40 micrometers or less, or about 30 micrometers or less.

[0118] The bright layer is not limited to the following, but may be a layer containing a metal selected from aluminum, nickel, gold, silver, copper, platinum, chromium, iron, tin, indium, titanium, lead, zinc, germanium, or the like, or an alloy or compound thereof, which is formed on the entirety or a part on a layer as a constituent of the laminate, for example, on the entire surface or a part of the first resin layer and / or the second resin layer, by vacuum deposition, sputtering, ion plating, plating, or the like. The thickness of the bright layer can be appropriately set according to the required decorativeness and the like.

[0119] The laminate of the present disclosure can use a bonding layer (sometimes referred to as a "primer layer" or the like) in order to bond an additional layer in the laminate. As the bonding layer, a generally used (meth)acrylic, polyolefin-based, polyurethane-based, polyester-based, rubber-based adhesive, or the like, solvent type, emulsion type, pressure-sensitive type, heat sensitive type, heat curable type, or radiation (e.g., ultraviolet ray) curable type adhesive can be used. The bonding layer can be applied by a known coating method or the like.

[0120] The laminate of the present disclosure may include an intermediate film layer. As the intermediate film layer, for example, a resin film of a resin having a urethane bond, polyvinyl chloride, a polyolefin such as polyethylene or polypropylene, a polyester such as polyethylene terephthalate or polybutylene terephthalate, or a (meth)acrylic polymer can be used.

[0121] The thickness of the intermediate film layer can be about 5 micrometers or more, about 10 micrometers or more, or about 15 micrometers or more, and about 200 micrometers or less, about 100 micrometers or less, or about 50 micrometers or less.

[0122] The laminate of the present disclosure may include an adhesive layer. As the adhesive layer, for example, a generally used (meth)acrylic, polyolefin-based, polyurethane -based, polyester-based, rubber-based or the like, solvent type, emulsion type, pressure -sensitive type, heat sensitive type, heat curable type, or radiation (e.g., ultraviolet ray) curable type adhesive can be used. The adhesive layer can be applied by a known coating method or the like.

[0123] The adhesive layer can contain as an optional component, for example, a filler, a conductive agent, a thermal conductivity imparting agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a dispersant, a lubricant, a surfactant, a leveling agent, a silane coupling agent, a catalyst, a colorant (e.g., a pigment and a dye), and the like to the extent that the effects of the present disclosure are not adversely affected.

[0124] The thickness of the adhesive layer of the present disclosure may be appropriately set in consideration of required adhesive force and the like. Such a thickness can be, for example, about 10 micrometers or more, about 20 micrometers or more, or about 30 micrometers or more, and can be about 300 micrometers or less, about 200 micrometers or less, or about 100 micrometers or less.

[0125] For the laminate of the present disclosure, a release liner can be typically applied to the adhesive layer. Examples of the release liner include: paper; a plastic material such as polyethylene, polypropylene, polyester (e.g., PET), and cellulose acetate; and paper coated with such a plastic material. These liners may have a surface that has been subjected to release treatment with a release agent such as silicone.

[0126] The thickness of the release liner can generally be about 5 micrometers or more, about 15 micrometers or more, or about 25 micrometers or more, and can be about 500 micrometers or less, about 300 micrometers or less, about 100 micrometers or less, or about 50 micrometers or less.

[0127] In some embodiments, the laminate of the present disclosure further includes a third resin layer containing a polylactic acid polymer, a (meth)acrylic block copolymer, and a plasticizer. These materials contained in such third resin layer and the blending amount thereof can be similar to those used in the first resin layer described above. For the thickness of the third resin layer, the same thickness as that of the first resin layer described above can be adopted. In some embodiments, the third resin layer may be allowed to function as a cover layer, a decorative layer, or an intermediate film layer in the same manner as the first resin layer described above, and in a case where the third resin layer functions as such a layer, the above-described materials, thicknesses, and the like can be appropriately adopted for the third resin layer to the extent that the effects of the present disclosure are not adversely affected. In some embodiments, the third resin layer may be disposed under the second resin layer 202, as illustrated in FIG 2, or may be disposed on the first resin layer 303, as illustrated in FIG 3.

[0128] Even if the third resin layer containing a polylactic acid polymer is provided, the laminate of the present disclosure is excellent in interlayer adhesion, and as a result, is also excellent in durability and elongation properties, because the first resin layer and the second resin layer are formed of a specific material.

[0129] The thickness of the laminate of the present disclosure is not particularly limited, and can be appropriately set according to the intended use and the like. The thickness of the laminate can be, for example, about 30 micrometers or more, about 50 micrometers or more, about 60 micrometers or more, about 80 micrometers or more, or about 100 micrometers or more, and can be about 1 mm or less, about 800 micrometers or less, about 500 micrometers or less, about 400 micrometers or less, about 300 micrometers or less, about 250 micrometers or less, about 200 micrometers or less, about 150 micrometers or less, about 130 micrometers or less, or about 120 micrometers or less. In some embodiments, even when the laminate of the present disclosure has such a thickness, particularly a relatively small thickness (e.g., about 200 micrometers or less), poor appearance such as wrinkles can be reduced or suppressed because the first resin layer contains a predetermined amount of a plasticizer and a (meth)acrylic block copolymer.

[0130] The laminate of the present disclosure may be, for example, a sheet-type product, a roll body wound in a roll shape, or a three-dimensional object.

[0131] In some embodiments, a surface of the laminate of the present disclosure after subjected to a durability test, which is, for example, 14 days of heat cycling from -30°C to 80°C, has no cracks.

[0132] In some embodiments, the laminate of the present disclosure can exhibit an elongation percentage of about 30% or more, about 40% or more, about 50% or more, or about 55% or more, and about 350% or less, about 300% or less, about 250% or less, about 200% or less, about 180% or less, or about 150% or less. In terms of reducing or suppressing poor appearance associated with the occurrence of wrinkles and in terms of workability on a cubic surface, the upper limit value of the elongation percentage is preferably about 250% or less, more preferably about 200% or less, and particularly preferably about 1800% or less.

[0133] In some embodiments, the laminate of the present disclosure can exhibit a yield strength of about 20 MPa or more, about 23 MPa or more, about 25 MPa or more, or more than about 25 MPa. The upper limit value of such yield strength is not particularly limited, and can be about 50 MPa or less, about 45 MPa or less, or about 40 MPa or less.

[0134] The following manufacturing method will be described as an example, but the manufacturing method of the laminate of the present disclosure is not limited thereto.

[0135] A master batch pellet containing a material as a constituent of the first resin layer described above is put into an extruder to form a film (a first resin layer) having a predetermined thickness. Next, to the resultant film is applied an acrylic pressure-sensitive adhesive composition by using a knife coater or the like, and if necessary, a drying step and a curing step are used to form an adhesive layer (a second resin layer). If necessary, a release liner can be applied to such an adhesive layer to produce a laminate.

[0136] In some embodiments, the laminate of the present disclosure described above is disposed on an adherend via an adhesive layer to provide an article including the laminate.

[0137] The material of the adherend to which the laminate can be applied is not particularly limited. Examples of such material include a resin material (e.g., a polyolefin resin, a polyester resin, a(meth)acrylic resin, a polycarbonate resin, a resin having a urethane bond, and an acrylonitrile-butadiene-styrene copolymer), an inorganic material (e.g., glass, ceramic, concrete, gypsum, calcium silicate, natural stone, asphalt), a rubber material, a cloth material (e.g., woven fabric, knitted fabric, and nonwoven fabric), a metal or a metal alloy material (e.g., iron, aluminum, stainless steel), and a wood-based material including paper.

[0138] The shape or configuration of the adherend is not particularly limited, and may be, for example, a planar shape (e.g., a film shape or a plate shape), a curved surface shape, an irregular shape, or a three-dimensional shape, and may be a single layer configuration, a laminated configuration, or a composite configuration in which a plurality of members having different shapes or different materials are combined.

[0139] The laminate of the present disclosure can be used in a variety of uses. Examples of such uses include signboards (e.g., internally illuminated signboards and externally illuminated signboards); signs (e.g., internally illuminated signs and externally illuminated signs); various interior or exterior articles such as interior or exterior articles for vehicles, such as automobiles, railways, aircrafts, and ships (e.g., roof members, pillar members, door trim members, instrument panel members, front members such as hoods, bumper members, fender members, side sill members, and interior panel members); and interior or exterior articles of buildings (e.g., window glass, doors, sashes, roof members such as tiling, outer wall members, and wall papers); electrical appliances, such as personal computers, smartphones, cellular phones, refrigerators, and air conditioners; stationery; furniture; desks; and various containers such as cans.

[0140] A method of applying the laminate of the present disclosure to an adherend (a support member) as a constituent of an article is not particularly limited, and a known method can be appropriately used. Examples of such method can include hand application, injection molding methods such as insert injection molding method, in-molding method, over-molding method, two-color injection molding method, core back injection molding method, and sandwich injection molding method, lamination method, and three-dimensional heat stretch blow molding method (Three dimension Overlay Method: TOM). The laminate of the present disclosure is excellent in durability (crack resistance etc.) and elongation properties, and poor appearance and the like associated with the occurrence of wrinkles can be reduced or suppressed, and hence the laminate of the present disclosure can be suitably used, for example, as a decorative laminate (a decorative film) applied to an adherend by hand application or the like.Examples

[0141] In the following examples, specific embodiments of the present disclosure are illustrated, but the present invention is not limited to these embodiments. All ‘part’ and ‘percent’ are based on mass unless otherwise specified. A numerical value essentially includes an error resulting from a measurement principle and a measuring device. The numerical value undergoes normal rounding and is indicated in significant digits.

[0142] Table 1 indicates various materials used. Note that, the "L-lactic acid" set forth in the table is intended to mean a polymerization unit derived from L-lactic acid, and the "D-lactic acid" is intended to mean a polymerization unit derived from D-lactic acid.

[0143] Table 1

[0144] Tables 2 and 3 indicate compositions of materials used when preparing the first resin layer or the third resin layer as a constituent of the laminate. Here, the "Amorphous PLA content proportion" in the table is intended to mean the proportion of the amorphous polylactic acid polymer to the total content of the polylactic acid polymer, the plasticizer, and the (meth)acrylic block copolymer, and the "Plasticizer content proportion" is intended to mean the proportion of the plasticizer to the total content of the plasticizer and the (meth)acrylic block copolymer.

[0145] Table 2

[0146] Table 3

[0147] <Test Example 1>In Test Example 1, typically, a laminate with a two-layer configuration was evaluated for durability and the like.

[0148] Example 1Pellets of pre-mixed polylactic acid polymer (PLA) having the composition of Table 2 were prepared with a twin screw extruder (zone 1: at about 149°C; zones 2 to 6: at about 177°C) and an underwater pelletizer. Note that, when a nucleating agent and a titanium dioxide white pigment were used in Examples and Comparative Examples, the following master batch pellets were used:Ecopromote (trade name) masterbatch (20 mass% in PLA4032 D)TiCE masterbatch (50 mass% in PLA4060D)

[0149] The pellets of the premixed PLA were fed into a single screw extruder and a polylactic acid polymer fdm was extruded to a polyester carrier fdm under conditions of zone 1 (at about 171°C), zone 2 (at about 177°C), and zones 3 to 5 (at about 182°C), and a die temperature of about 182°C. The thickness of such polylactic acid polymer fdm (a first resin layer) was about 75 micrometers.

[0150] Next, a monomer mixture of butyl acrylate / acrylic ester is copolymerized in ethyl acetate and thereby preparing an acrylic copolymer solution (solid content: 38 mass%) as an acrylic pressuresensitive adhesive (PSA) composition. The resultant pressure-sensitive adhesive composition was applied to the polylactic acid polymer film using a knife coater. The thickness of the adhesive layer (a second resin layer) after drying was about 38 micrometers.

[0151] Examples 2 to 9 and Comparative Examples 1 to 7Laminates of Examples 2 to 9 and Comparative Examples 1 to 7 each were obtained in the same manner as in Example 1 except that the compositions were changed to those in Table 2 or Table 3.

[0152] Evaluation test 1Each of the resultant test samples was evaluated according to the following test method. The results are listed in Tables 4 and 5.

[0153] Durability test (evaluation of crack resistance)A test sample of each laminate was bonded to an A5052P aluminum plate (available from Paltek Corporation (Hiratsuka-shi, Kanagawa, Japan)) with a roller under an environment of 23 °C, and the sample was allowed to stand for 24 hours. Thereafter, aging was performed under a thermal cycle of from -30°C to +80°C for 14 days, and the appearance was visually inspected. In the table, "Poor" is filled in for a case where a crack had occurred, and "Good" is filled in for a case where no crack had occurred.

[0154] Elongation testThe laminate was cut into a size of a width of 25 mm and a length of 100 mm to prepare a test piece. The elongation and the yield strength of the test piece were measured with a tensile tester (TENSILON universal testing machine (model: RTC-1210A), available from A&D Company, Limited (Toshima-ku, Tokyo, Japan)) under the conditions of 23°C, a gauge length of 50 mm, and a crosshead speed of 100 mm / min. Here, the elongation is defined by the following equation: Elongation percentage (%) = (Final length of test piece - Initial length of test piece) / Initial length of test piece. For the yield strength, N / 25 mm is converted to MPa based on the sizes of the thickness and the width of each film. In the table, "B" is intended to mean good, and "A" is intended to mean best. More specific evaluations are given below:• A test piece having an elongation of 50% or more was rated as "A", a test piece having an elongation percentage of 30% or more and less than 50% was rated as "B", and a test piece having an elongation percentage of less than 30% was rated as "C".• A test piece having a yield strength of 25 MPa or more was rated as "A", a test piece having a yield strength of 20 MPa or more and less than 25 MPa was rated as "B", and a test piece having a yield strength of less than 20 MPa was rated as "C".

[0155] Appearance test (evaluation of yellowing resistance)The values of L*, a*, and b* of test samples before and after the durability test were measured with a spectrophotometer (CM-3700d, available from KONICA MINOLTA, INC. (Chiyoda-ku, Tokyo, Japan)). The measured values before aging were denoted by L , af, and bi*, and the measured values after aging were denoted by L2*, a2*, and b2*. A color difference (AE) was calculated from Equation 1 set forth below:- • - Equation iHere, a sample having a AE value of 3 or less was rated as “A”, and a sample having a AE value of more than 3 was rated as“B”.

[0156] Table d

[0157] Table 5

[0158] <Test Example 2>In Test Example 2, a laminate with a three-layer configuration illustrated in FIG. 3 was evaluated for durability and the like. The layer configuration of the laminate is summarized in Table 6 below. Here, Examples or Comparative Examples set forth in the columns of “First resin layer” to “Third resin layer” in the table are intended to mean that polylactic acid polymer films of the indicated Examples or Comparative Examples were used.

[0159] Table 6

[0160] Example 10The polylactic acid polymer film obtained in Examples 3 and 4 described above were used and a film having a two-layer configuration was thermally laminated with preheat roll 1: at 135°C, preheat roll 2: at 145°C, IR heater: at 500°C, and embossing roll (satin pattern): at 60°C to afford a laminated film. Here, the surface to which the embossing roll was applied was the side of the film of Example 3 (Third resin layer).

[0161] Next, a monomer mixture of butyl acrylate / acrylic ester is copolymerized in ethyl acetate and thereby preparing an acrylic copolymer solution (solid content: 38 mass%) as an acrylic pressuresensitive adhesive (PSA) composition. The resulting pressure -sensitive adhesive composition was applied, by using a knife coat, to a surface of the laminated film opposite to the embossed surface. The thickness of the adhesive layer (a second resin layer) after drying was about 38 micrometers.

[0162] Examples 11 to 15 and Comparative Example 8Laminates of Examples 11 to 15 and Comparative Example 8 each were obtained in the same manner as in Example 10 except that First resin layer and Third resin layer were changed to polylactic acid polymer films of Examples or Comparative Examples set forth in Table 6.

[0163] Evaluation test 2Each of the resultant test samples was evaluated according to the test method (durability test and appearance test) in Evaluation Test 1 described above and the following test method. The results are listed in Table 7.

[0164] Elongation testThe laminate was cut into a size of a width of 25 mm and a length of 100 mm to prepare a test piece. The elongation and yield strength of the test piece were measured with a tensile tester (TENSILON universal testing machine (model: RTC-1210A), available from A&D Company, Limited (Toshima-ku, Tokyo, Japan)) under the conditions of 20°C, a gauge length of 50 mm, and a crosshead speed of 300 mm / min. Here, the elongation is defined by the following equation: Elongation percentage (%) = (Final length of test piece - Initial length of test piece) / Initial length of test piece. For the yield strength, N / 25mm is converted to MPa based on the sizes of the thickness and the width of each fdm. In the table, "B" is intended to mean good, and "A" is intended to mean best. More specific evaluations are given below:• A test piece having an elongation of 50% or more was rated as "A", a test piece having an elongation percentage of 30% or more and less than 50% was rated as "B", and a test piece having an elongation percentage of less than 30% was rated as "C".• A test piece having a yield strength of 25 MPa or more was rated as "A", a test piece having a yield strength of 20 MPa or more and less than 25 MPa was rated as "B", and a test piece having a yield strength of less than 20 MPa was rated as "C".

[0165] Dimensional stability testThe laminate was cut into a size of length and width of 50 mm to prepare a test piece. This test piece was bonded to an A5052P aluminum plate (available from Paltek Corporation (Hiratsuka-shi, Kanagawa, Japan)) with a roller under an environment of 23 °C, and allowed to stand under an environment of 23°C for 24 hours. A cross cut was made in the test piece with a cutter, and then the test piece was heated at 65°C for 48 hours. After aging, the shrinkage (mm) of the film was measured with a microscope, and the maximum value was recorded. A test piece having a shrinkage of less than 0.5 mm was rated as "A", and a test piece having a shrinkage of 0.5 mm or more was rated as "B".

[0166] Table 7

[0167] It is apparent for a person skilled in the art that various variations of the embodiments and examples described above can be made without departing from the basic principles of the present invention. Moreover, it is apparent for a person skilled in the art that various modifications and variations of the present invention can be made without departing from the spirit and scope of the present invention.

Claims

Claims1. A laminate, comprising a first resin layer and a second resin layer,the first resin layer comprising a polylactic acid polymer, a (meth)acrylic block copolymer, and a plasticizer, wherein a content of the plasticizer is 1 mass% or more and less than 10 mass%, the second resin layer comprising at least one selected from the group consisting of a (meth)acrylic resin, a resin having a urethane bond, and a vinyl chloride-vinyl acetate copolymer resin, andthe laminate comprising a portion to which the first resin layer and the second resin layer are directly applied.

2. The laminate according to claim 1, comprising an amorphous polylactic acid polymer as the polylactic acid polymer.

3. The laminate according to claim 2, wherein a content of the amorphous polylactic acid polymer is 50 mass% or more with respect to a total amount of the polylactic acid polymer.

4. The laminate according to any one of claims 1 to 3, wherein a content of the polylactic acid polymer is 20 mass% or more and 70 mass% or less, and a content of the (meth)acrylic block copolymer is 10 mass% or more and 25 mass% or less, with respect to a total amount of the first resin layer.

5. The laminate according to any one of claims 1 to 3, wherein a content proportion of the plasticizer to a total content of the (meth)acrylic block copolymer and the plasticizer is 10 mass% or more and 50 mass% or less.

6. The laminate according to any one of claims 1 to 3, wherein the first resin layer further comprises at least one selected from the group consisting of a polyvinyl acetate polymer and an antioxidant.

7. The laminate according to any one of claims 1 to 3, further comprising a third resin layer comprising: a polylactic acid polymer; a (meth)acrylic block copolymer; and a plasticizer.

8. The laminate according to any one of claims 1 to 3, wherein a surface of the laminate after subjected to 14 days of heat cycling from -30°C to 80°C has no cracks.

9. The laminate according to any one of claims 1 to 3, wherein the laminate has an elongation percentage of 30% or more.

10. The laminate according to any one of claims 1 to 3, which is to be used as a decoration.

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