Laminate including adhesive layer, adhesive composition, and method for producing adhesive composition

Abstract

A laminate including an adhesive layer that can contribute to reduction in an amount of petroleum resources used and can expand a physical property range of the adhesive. A laminate includes: an adhesive layer including a first copolymer including a constituent unit derived from a carboxyl group-containing monomer, a second copolymer including a constituent unit derived from an amino group-containing monomer, and a cured product of a crosslinking agent; and a substrate. The first copolymer has a weight average molecular weight of about 800,000 or less and a glass transition temperature of lower than about 0°C, the second copolymer has a weight average molecular weight of about 30,000 or more and about 100,000 or less and a glass transition temperature of about 0°C or higher. At least one of the first copolymer and the second copolymer includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom.

Description

PA102134W002LAMINATE INCLUDING ADHESIVE LAYER, ADHESIVE COMPOSITION, AND METHOD FOR PRODUCING ADHESIVE COMPOSITIONTechnical Field

[0001] The present disclosure relates to a laminate including an adhesive layer, an adhesive composition, and a method for producing the adhesive composition.Background Art

[0002] In recent years, a laminate such as an adhesive tape including an adhesive layer formed using a biologically derived material in place of a petroleum -derived material has been developed.

[0003] Patent Document 1 (JP 2012-514083 W) describes an adhesive including a reaction product of (a) at least one polymerizable (meth)acrylate monomer derived at least in part from palm oil, coconut oil, tallow, or lard; (b) an initiator; and (c) a stabilizer, wherein such a reaction occurs in water to yield a microsphere adhesive, and an adhesive article including the adhesive disposed on a polymer fdm or the like.

[0004] Patent Document 2 (JP 2019-218458 A) describes an adhesive tape including an adhesive layer containing a (meth)acrylic copolymer including a constituent unit derived from a (meth)acrylic monomer containing biologically derived carbon, in which the content of biologically derived carbon in the adhesive tape is 30 wt.% or more.Citation ListPatent Documents

[0005] Patent Document 1 : JP 2012-514083 WPatent Document 2: JP 2019-218458 ASummary of InventionTechnical Problem

[0006] As described in Patent Documents 1 and 2, an adhesive formed using a biologically derived material generally contains only one copolymer formed using the biologically derived material. Thus, it may be difficult to adjust the physical properties of such an adhesive within a desired range.

[0007] The present disclosure provides a laminate including an adhesive layer that can contribute to reduction in an amount of petroleum resources used and can expand a physical property range of the adhesive, an adhesive composition, and a method for producing the adhesive composition.Solution to Problem

[0008] According to one embodiment of the present disclosure, provided is a laminate including: an adhesive layer including a first copolymer including a constituent unit derived from a carboxyl group-containing monomer, a second copolymer including a constituent unit derived from an amino group- containing monomer, and a cured product of a crosslinking agent; and a substrate, in which the first copolymer has a weight average molecular weight of about 800,000 or less and a glass transition temperature of lower than 0°C, the second copolymer has a weight average molecular weight of about 30,000 or more and about 100,000 or less and a glass transition temperature of about 0°C or higher, and at least one of the first copolymer and the second copolymer includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom.

[0009] According to another embodiment of the present disclosure, provided is an adhesive composition including: a first copolymer including a constituent unit derived from a carboxyl group- containing monomer; a second copolymer including a constituent unit derived from an amino group- containing monomer; and a crosslinking agent, in which the first copolymer has a weight average molecular weight of about 800,000 or less and a glass transition temperature of lower than about 0°C, the second copolymer has a weight average molecular weight of about 30,000 or more and about 100,000 or less and a glass transition temperature of about 0°C or higher, and at least one of the first copolymer and the second copolymer includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom.

[0010] According to another embodiment of the present disclosure, provided is a method for producing the adhesive composition, the production method including mixing a first copolymer, a second copolymer, and a crosslinking agent.

[0011] According to another embodiment of the present disclosure, provided is method for producing the adhesive composition including a pigment, the production method including mixing at least one selected from the group consisting of a second copolymer and a third copolymer including a constituent unit derived from an amide group-containing monomer with a pigment to prepare a pigment mixture, and mixing the pigment mixture with a mixture containing the first copolymer and a crosslinking agent, or mixing at least one selected from the group consisting of the second copolymer and the third copolymer including a constituent unit derived from an amide group-containing monomer, the crosslinking agent, and the pigment to prepare a pigment mixture, and mixing the pigment mixture with the first copolymer.Advantageous Effects of Invention

[0012] According to the present disclosure, it is possible to provide a laminate including an adhesive layer that can contribute to reduction in an amount of petroleum resources used and can expand a physical property range of the adhesive, an adhesive composition, and a method for producing the adhesive composition.

[0013] The above description is not to be construed as having disclosed all the embodiments of the present invention nor all the advantages related to the present invention.Brief Description of Drawings

[0014] FIG. 1 is a schematic cross-sectional view of a laminate according to an embodiment of the present disclosure.Description of Embodiments

[0015] The present invention will be described in further detail hereinafter, referring to figures as necessary, with the purpose of illustrating representative embodiments of the present invention, but the present invention is not limited to these embodiments.

[0016] In the present disclosure, the term “on” used, for example, in the phrase “an adhesive layer disposed on a release liner” means that the adhesive layer is disposed directly on the upper side of the release liner, or, that the adhesive layer is indirectly disposed on the upper side of the release liner via another layer.

[0017] In the present disclosure, the term “under”, for example, in “adhesive layer disposed under a substrate” means that the adhesive layer is disposed directly below the substrate, or that the adhesive layer is indirectly disposed below the substrate via another layer.

[0018] In the present disclosure, "transparent" refers to an average transmittance in a visible light region (wavelength of 400 nm to 700 nm) measured in accordance with JIS K 7375 of approximately 80% or more, and the average transmittance may be desirably approximately 85% or more, or approximately 90% or more. An upper limit of the average transmittance is not particularly limited, and can be, for example, approximately less than 100%, approximately 99% or less, or approximately 98% or less.

[0019] In the present disclosure, the term “translucent” refers to an average transmittance in a visible light region (wavelength of 400 nm to 700 nm) measured in accordance with JIS K 7375 of approximately less than 80%, and the average transmittance may be desirably approximately 75% or less, and “translucent” is intended to mean that an underlying layer or the like is not completely hidden.

[0020] In the present disclosure, the term "film" encompasses articles referred to as "sheets".

[0021] In the present disclosure, “(meth)acrylic” means acrylic or methacrylic, “(meth)acrylate” means acrylate or methacrylate, and “(meth)acryloyl” means acryloyl or methacryloyl.

[0022] FIG. 1 shows a schematic cross-sectional view of a laminate according to an embodiment of the present disclosure. The laminate 100 in FIG. 1 includes a substrate 10, an adhesive layer 20 and a release liner 30. Here, the release liner shown in FIG. 1 is an optional layer, and the laminate of the present disclosure may not include a release liner. In addition, the laminate of the present disclosure may include any layer (for example, a decorative layer described later.

[0023] An adhesive force of the laminate of the present disclosure can be evaluated by an adhesive force test which will be described later. In some embodiments, the laminate of the present disclosure can exhibit an adhesive force of about 5.0 N / 25 mm or more, about 6.0 N / 25 mm or more, about 7.0 N / 25 mm or more, or about 8.0 N / 25 mm or more under a room temperature environment when a melamine- coated plate is used as an adherend to which an adhesive layer is applied. The upper limit of the adhesiveforce can be, for example, about 40.0 N / 25 mm or less, about 35.0 N / 25 mm or less, about 30.0 N / 25 mm or less, about 25.0 N / 25 mm or less, about 20.0 N / 25 mm or less, about 19.0 N / 25 mm or less, about 18.5 N / 25 mm or less, or about 18.0 N / 25 mm or less. Here, the “room temperature” in the present disclosure is intended to be a temperature in a room in which a test is performed, and specifically may be intended to be, for example, about 23°C ± about 5°C or about 23°C ± about 3°C.

[0024] In some embodiments, the laminate of the present disclosure can exhibit an adhesive force of about 5.0 N / 25 mm or more, about 6.0 N / 25 mm or more, about 6.5 N / 25 mm or more, or about 7.0 N / 25 mm or more under a room temperature environment when an aluminum plate is used as an adherend to which an adhesive layer is applied. The upper limit of the adhesive force can be, for example, about 40.0 N / 25 mm or less, about 35.0 N / 25 mm or less, about 30.0 N / 25 mm or less, about 25.0 N / 25 mm or less, about 24.0 N / 25 mm or less, about 23.5 N / 25 mm or less, or about 23.0 N / 25 mm or less.

[0025] In some embodiments, the laminate of the present disclosure exhibits heat resistance. Such heat resistance can be evaluated by a heat shrinkage test described later. In some embodiments, the laminate of the present disclosure can achieve about 0.50 mm or less, about 0.40 mm or less, about 0.30 mm or less, or about 0.25 mm or less relative to a maximum width of opening (mouth opening) of a cut after the heat shrinkage test. The lower limit of such width is not particularly limited, and can be, for example, about 0 mm or more.

[0026] The adhesive layer of the present disclosure can contain a pigment, so that the resulting laminate can exhibit concealing properties. The concealing properties can be evaluated by a color difference in a test of the concealing properties described later. In some embodiments, the laminates of the present disclosure exhibit a color difference of less than about 12, about 10 or less, about 8.0 or less, about less than 6.0, about 5.0 or less, or about 4.0 or less. The lower limit of such color difference is not particularly limited, and may be, for example, about 0 or more or more than about 0.

[0027] In some embodiments, the laminate of the present disclosure exhibits elongation properties. Such elongation properties can be evaluated by a yield point evaluation test, an elongation test, and a tensile strength test described later. In some embodiments, the laminate of the present disclosure can exhibit a yield point of about 10 N / 25 mm or more, about 15 N / 25 mm or more, or about 20 N / 25 mm or more, about 70 N / 25 mm or less, about 65 N / 25 mm or less, about 60 N / 25 mm or less, about 55 N / 25 mm or less, or about 50 N / 25 mm or less, can exhibit an elongation of about 20% or more, about 25% or more, about 30% or more, about 40% or more, about 50% or more, about 60% or more, about 70% or less, about 80% or less, or about 90% or more, about 160% or less, about 150% or less, about 140% or less, about 130% or less, or about 125% or less, and can exhibit a 2% tensile strength of about 5 N / 25 mm or more, about 10 N / 25 mm or more, or about 15 N / 25 mm or more, about 50 N / 25 mm or less, about 40 N / 25 mm or less, about 30 N / 25 mm or less, or about 25 N / 25 mm or less.

[0028] In some embodiments, the laminate of the present disclosure exhibits followability and, as a result, a gloss retention performance. Such gloss retention performance can be evaluated by a gloss retention described later. In some embodiments, the laminate of the present disclosure may exhibit a gloss retention of less than about 200%, about 150% or less, about 130% or less, or about 120% or less.The lower limit of such retention is not particularly limited, and can be, for example, about 50% or more, about 80% or more, or about 100% or more.

[0029] The laminate of the present disclosure includes an adhesive layer containing a cured product of a first copolymer, a second copolymer, and a crosslinking agent. Since these copolymers are polymers that can be further crosslinked with the crosslinking agent, the first copolymer and the second copolymer before being crosslinked with the crosslinking agent can also be referred to as “first partial polymer” and “second partial polymer”. In the present disclosure, the “cured product” is not limited to a crosslinking reactant in which a crosslinking reactive site in the first copolymer and / or the second copolymer is completely subjected to a crosslinking reaction, and may include a crosslinking reactant in which a part of the crosslinking reactive site remains without being subjected to the crosslinking reaction.

[0030] The first copolymer included in the adhesive layer includes a constituent unit derived from a carboxyl group-containing monomer, and has a weight average molecular weight of about 800,000 or less and a glass transition temperature of lower than about 0°C.

[0031] The weight average molecular weight of the first copolymer can be about 700,000 or less, about 600,000 or less, about 500,000 or less, about 450,000 or less, about 430,000 or less, about 400,000 or less, about 380,000 or less, or about 350,000 or less, and can be about 100,000 or more, about 150,000 or more, about 200,000 or more, or about 210,000 or more. The “weight average molecular weight” and the “molecular weight distribution” represented by weight average molecular weight (Mw) / number average molecular weight (Mn) in the present disclosure can be measured by a GPC method (gel permeation chromatography method). For example, the following conditions can be adopted as the measurement conditions:Apparatus: HP- 1090 Series II (available from Hewlett-Packard Company) Solvent: tetrahydrofuranColumn: Plgel MIXED-Bx2 (300 mm, outer diameter: 7.5 mm, inner diameter: 5 mm) Flow rate: 1. 0 mL / minDetecting means : refractive index Sample concentration: 0.1 wt.% Calibration standard: polystyrene

[0032] In some embodiments, the molecular weight distribution of the first copolymer is about 10 or less. Such a molecular weight distribution can be about 8.0 or less, about 7.0 or less, about 6.0 or less, or about 5.0 or less. The lower limit of the molecular weight distribution is not particularly limited, and can be about 0 or more, about 1.0 or more, about 2.0 or more, or about 3.0 or more. When such a first copolymer having a narrow molecular weight distribution is used, a solid content of an adhesive composition can be increased, and a viscosity of an adhesive can be reduced. When an adhesive composition having a high solid content can be used, for example, energy required for drying the adhesive layer can be reduced, and as a result, it is possible to suitably contribute to an environmental problem. The use of the first copolymer having a narrow molecular weight distribution can reduce a proportion of a low-molecular-weight copolymer that causes a decrease in adhesive force, and thus canimprove performance such as adhesive force as compared with an adhesive layer prepared using a copolymer having a wide molecular weight distribution.

[0033] The glass transition temperature of the first copolymer can be about -5°C or lower, about - 10°C or lower, about -20°C or lower, about -30°C or lower, about -40°C or lower, about -43°C or lower, about -45 °C or lower, about -47°C or lower, or about -50°C or lower, and can be about -100°C or higher, about -80°C or higher, about -70°C or higher, about -65°C or higher, or about -60°C or higher. The “glass transition temperature (Tg)” of the present disclosure can be determined as a calculated glass transition temperature by using the following Fox formula (Fox, T. G., Bull. Am. Phys. Soc., 1 (1956), p. 123) when the polymer is formed by copolymerization of n types of monomers:[Math. 1] n_ 1 _ = y ( _x-i _ ) Tg + 273.15 4 '.Tg, + 273.157In the formula, Tgi represents the glass transition temperature (°C) of a homopolymer of a component i, Xi represents the mass fraction of the monomer of the component i added during polymerization, and i is a natural number of 1 to n, and[Math. 2]

[0034] The first copolymer including a constituent unit derived from a carboxyl group-containing monomer can be obtained by copolymerization of a monoethylenically unsaturated monomer and a carboxy group-containing unsaturated monomer.

[0035] The monoethylenically unsaturated monomer typically includes (meth)acylates represented by the formula CH2=CR1COOR2(in the formula, R1is hydrogen or a methyl group, and R2is a linear, branched, or cyclic alkyl group, a phenyl group, an alkoxyalkyl group, a phenoxyalkyl group, a hydroxyalkyl group, or a cyclic ether group), and additionally, aromatic vinyl monomers such as styrene, a-methylstyrene, and vinyl toluene, vinyl esters such as vinyl acetate, and unsaturated nitriles such as acrylonitrile and methacrylonitrile. Examples of the monoethylenically unsaturated monomer represented by CH2=CR1COOR2can include linear alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, n-hexyl (meth)acrylate, n-decyl (meth)acrylate, and n-dodecyl (meth)acrylate; branched alkyl (meth)acrylates such as isoamyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, and isononyl (meth)acrylate; alicyclic (meth)acrylates such as cyclohexyl (meth)acrylate and isobomyl (meth)acrylate; phenyl (meth)acrylates; alkoxyalkyl (meth)acrylates such as methoxypropyl (meth)acrylate and 2-methoxybutyl (meth)acrylate; phenoxyalkyl (meth)acrylates such as phenoxyethyl (meth)acrylate; hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; and cyclic ether-containing (meth)acrylates such as glycidyl (meth)acrylate and tetrahydrofurfuryl (meth)acrylate. Among them, n-butyl (meth)acrylate is preferable from the viewpoint of compatibility with the second copolymer described later, adhesive force, heat shrinkage resistance, and the like. The monoethylenically unsaturated monomers can be used alone, or two or more types thereof can be used in combination.

[0036] As the monoethylenically unsaturated monomer, a (meth)acrylate monomer containing a biologically derived carbon atom may be used. The (meth)acrylate monomer containing a biologically derived carbon atom may be used alone or two or more types thereof may be used in combination. The present inventor has found that by adopting a specific first copolymer and a specific second copolymer described later, even if at least one of these copolymers includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom, performance equivalent to that of an adhesive similarly prepared using a known petroleum-derived material can be exhibited. From the viewpoint of adhesive force, heat shrinkage resistance, and the like, the first copolymer preferably includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom (hereinafter, the constituent unit is sometimes referred to as a “biologically derived constituent unit”), and in addition to the biologically derived constituent unit, it is more preferable that the first copolymer also includes a constituent unit derived from the above-described monoethylenically unsaturated monomer other than the biologically derived constituent unit, that is, the first copolymer is a terpolymer or higher order polymer (for example, a terpolymer). When the first copolymer also includes a constituent unit derived from the above-described monoethylenically unsaturated monomer other than the biologically derived constituent unit, it is possible to adjust the performance such as compatibility with the second copolymer described later and, when present, a third copolymer, and as a result, it is easy to exhibit desired physical properties in the adhesive layer, and it is also possible to improve the adhesiveness to the substrate. From the viewpoint of improving the performance such as the compatibility with the second copolymer described later and the third copolymer when present, the first copolymer preferably contains the same or the same kind of constituent unit as the constituent unit derived from the monoethylenically unsaturated monomer included in the second copolymer and / or the third copolymer. In the present disclosure, the “same kind of constituent unit” can mean a constituent unit containing monomers having the same main skeleton, such as n-butyl acrylate and n-butyl methacrylate.

[0037] The biologically derived carbon atom contains a certain percentage of a radioactive isotope (C- 14), whereas a petroleum-derived carbon atom contains a few radioactive isotopes C-14. Thus, the content of the biologically derived carbon atom can be calculated by measuring the concentration of C-14 contained in the laminate or the adhesive composition. Specifically, the concentration can be measured according to ASTM D6866 of a standard used in the bioplastic industry.

[0038] As the (meth)acrylate monomer containing a biologically derived carbon atom, a (meth)acrylate monomer containing a plant-derived carbon atom is preferable from the viewpoints of adhesive force, heat shrinkage resistance, and the like. Examples of such plants include palm oil andcoconut oil. From the viewpoint of adhesive force, heat shrinkage resistance, and the like, the (meth)acrylate monomer is preferably a (meth)acrylate monomer having an alkyl group having 4 or more, 5 or more, or 6 or more and 12 or less, 10 or less, or 8 or less carbon atoms, and more preferably at least one selected from the group consisting of n-octyl (meth)acrylate and 2-octyl (meth)acrylate.

[0039] When the first copolymer does not include the biologically derived constituent unit, a proportion of the constituent unit derived from the above-described monoethylenically unsaturated monomer other than the biologically derived constituent unit can be, for example, about 85 mass% or more, about 90 mass% or more, or about 92 mass% or more, and about 99.5 mass% or less, about 99 mass% or less, or about 98 mass% or less relative to the first copolymer. When the first copolymer contains the biologically derived constituent unit, the proportion of such a constituent unit can be, for example, about 40 mass% or more, about 50 mass% or more, about 55 mass% or more, or about 60 mass% or more, and about 99.5 mass% or less, about 95 mass% or less, about 90 mass% or less, about 80 mass% or less, about 75 mass% or less, about 70 mass% or less, or about 65 mass% or less relative to the first copolymer, and when the biologically derived constituent unit is present, the proportion of the constituent unit derived from the above-described monoethylenically unsaturated monomer other than the biologically derived constituent unit can be, for example, about 10 mass% or more, about 15 mass% or more, about 20 mass% or more, about 25 mass% or more, or about 30 mass% or more, about 50 mass% or less, about 45 mass% or less, about 40 mass% or less, or about 35 mass% or less relative to the first copolymer.

[0040] Examples of the carboxy group-containing unsaturated monomer include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; unsaturated dicarboxylic acids such as itaconic acid, fumaric acid, citraconic acid, and maleic acid; co-carboxy polycaprolactone monoacrylate, phthalic acid monohydroxyethyl (meth)acrylate, [3-carboxyethyl acrylate, 2-(meth)acryloyl oxyethyl succinate, and 2-(meth)acryloyl oxyethyl hexahydrophthalate. The carboxy group-containing unsaturated monomers can be used alone, or two or more types thereof can be used in combination.

[0041] A proportion of the constituent unit derived from the carboxy group-containing unsaturated monomer can be about 0.5 mass% or more, about 1 mass% or more, or about 2 mass% or more, and about 15 mass% or less, about 10 mass% or less, or about 8 mass% or less relative to the first copolymer.

[0042] The second copolymer included in the adhesive layer includes a constituent unit derived from an amino group-containing monomer, and has a weight average molecular weight of about 30,000 or more and about 100,000 or less and a glass transition temperature of about 0°C or higher.

[0043] The weight average molecular weight of the second copolymer can be about 35,000 or more, about 40,000 or more, about 45,000 or more, about 50,000 or more, about 55,000 or more, or about 60,000 or more, and can be about 90,000 or less, about 85,000 or less, about 80,000 or less, about 75,000 or less, or about 70,000 or less.

[0044] In some embodiments, the molecular weight distribution of the second copolymer is about 10 or less. Such a molecular weight distribution can be about 8.0 or less, about 7.0 or less, about 6.0 or less, or about 5.0 or less. The lower limit of the molecular weight distribution is not particularly limited, andcan be about 0 or more, about 1.0 or more, about 2.0 or more, or about 3.0 or more. When such a second copolymer having a narrow molecular weight distribution is used, a solid content of an adhesive composition can be increased, and a viscosity of an adhesive can be reduced. When an adhesive composition having a high solid content can be used, for example, energy required for drying the adhesive layer can be reduced, and as a result, it is possible to suitably contribute to an environmental problem. The use of the second copolymer having a narrow molecular weight distribution can reduce the proportion of the low-molecular-weight copolymer that causes the decrease in adhesive force, and thus can improve performance such as adhesive force as compared with an adhesive layer prepared using a copolymer having a wide molecular weight distribution.

[0045] The glass transition temperature of the second copolymer can be about 10°C or higher, about20°C or higher, about 30°C or higher, about 40°C or higher, about 45°C or higher, about 50°C or higher, about 55°C or higher, or about 60°C or higher, and can be about 100°C or lower, about 90°C or lower, about 80°C or lower, about 75°C or lower, about 70°C or lower, or about 65°C or lower.

[0046] The second copolymer including a constituent unit derived from an amino group-containing monomer can be obtained by copolymerization of a monoethylenically unsaturated monomer and an amino group-containing unsaturated monomer.

[0047] As the monoethylenically unsaturated monomer, the monoethylenically unsaturated monomer in the first copolymer described above can be similarly used. Among them, methyl (meth)acrylate and n- butyl (meth)acrylate are preferable from the viewpoint of compatibility with the first copolymer described above, adhesive force, heat shrinkage resistance, and the like. The monoethylenically unsaturated monomers can be used alone, or two or more types thereof can be used in combination. From the viewpoint of improving the performance such as the compatibility with the first copolymer described above and the third copolymer when present, the second copolymer preferably contains the same or the same kind of constituent unit as the constituent unit derived from the monoethylenically unsaturated monomer included in the first copolymer and / or the third copolymer.

[0048] Also in the second copolymer, similarly to the first copolymer, a (meth)acrylate monomer containing a biologically derived carbon atom may be used. As such a monomer, those described above can be similarly employed.

[0049] When the second copolymer does not contain the biologically derived constituent unit, the proportion of the constituent unit derived from the monoethylenically unsaturated monomer other than the biologically derived constituent unit can be, for example, about 85 mass% or more, about 90 mass% or more, or about 92 mass% or more, and about 99.5 mass% or less, about 99 mass% or less, or about 98 mass% or less relative to the second copolymer. When the second copolymer contains the biologically derived constituent unit, the proportion of such a constituent unit can be, for example, about 40 mass% or more, about 50 mass% or more, about 55 mass% or more, or about 60 mass% or more, and about 99.5 mass% or less, about 95 mass% or less, about 90 mass% or less, about 80 mass% or less, about 75 mass% or less, about 70 mass% or less, or about 65 mass% or less relative to the second copolymer, and when the biologically derived constituent unit is present, the proportion of the constituent unit derivedfrom the monoethylenically unsaturated monomer other than the biologically derived constituent unit can be, for example, about 10 mass% or more, about 15 mass% or more, about 20 mass% or more, about 25 mass% or more, or about 30 mass% or more, about 50 mass% or less, about 45 mass% or less, about 40 mass% or less, or about 35 mass% or less relative to the second copolymer.

[0050] Examples of the amino group-containing unsaturated monomer include dialkylaminoalkyl (meth)acrylates such as N,N-dimethylaminoethyl acrylate (DMAEA) and N,N-dimethylaminoethyl methacrylate (DMAEMA); dialkylaminoalkyl (meth)acrylamides such as N,N-dimethylaminopropyl acrylamide (DMAPAA) and N,N-dimethylaminopropyl methacrylamide; dialkylaminoalkyl vinyl ethers such as N,N-dimethylaminoethyl vinyl ether and N,N-diethylaminoethyl vinyl ether; and monomers having a tertiary amino group, e.g., vinyl monomers having a nitrogen-containing heterocycle such as vinylimidazole. The amino group-containing unsaturated monomers can be used alone, or two or more types thereof can be used in combination.

[0051] A proportion of the constituent unit derived from the amino group-containing monomer can be about 0.5 mass% or more, about 1 mass% or more, or about 2 mass% or more, and about 15 mass% or less, about 10 mass% or less, or about 8 mass% or less relative to the second copolymer.

[0052] The first and second copolymers (partial polymers) can be prepared using, for example, radical polymerization, and can be prepared by known polymerization methods such as solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization. Examples of the initiator include organic peroxides such as benzoyl peroxide, lauroyl peroxide, and bis(4-tert-butylcyclohexyl) peroxy dicarbonate, and azo-based polymerization initiators such as 2,2'- azobisisobutyronitile, 2, 2'-azobis(2 -methylbutyronitrile), dimethyl 2, 2'-azobis(2 -methylpropionate), 4,4'- azobis(4-cyanovaleric acid), and 2,2'-azobis(2,4-dimethylvaleronitrile) (AVN). An amount of the initiator used can be, for example, about 0.01 parts by mass or more or about 0.05 parts by mass or more, and about 5 parts by mass or less or about 3 parts by mass or less, relative to 100 parts by mass of the monomer mixture.

[0053] The adhesive layer of the present disclosure can be prepared using an adhesive composition containing the first and second copolymers (partial polymers) and a crosslinking agent, for example, a solvent-type, an emulsion-type, a pressure-sensitive type, a heat-sensitive type, a heat-curable type, or a radiation (e.g., ultraviolet) curable type adhesive composition. By using a composition containing a crosslinking agent, the adhesive layer containing a cured product of the copolymer and the crosslinking agent can have a crosslinked structure. As the crosslinking agent, for example, a thermal crosslinking agent and a radiation crosslinking agent (for example, an ultraviolet crosslinking agent) can be used, and specifically, an epoxy crosslinking agent, a bisamide crosslinking agent, an aziridine crosslinking agent, a carbodiimide crosslinking agent, and the like can be used. The crosslinking agents can be used alone, or two or more types thereof can be used in combination. The adhesive layer of the present disclosure is not particularly limited, and can be, for example, a heat-sensitive type adhesive layer or a pressure-sensitive type adhesive layer. These types of adhesive layers can be adjusted, for example, by the type or blendingratio of the first copolymer and the second copolymer, or by the type or blending ratio of the crosslinking agent.

[0054] Examples of the epoxy crosslinking agents include N,N,N',N'-tetraglycidyl-l,3- benzenedi(methanamine) (product name: TETRAD-X (Mitsubishi Gas Chemical Company Inc., Chiyoda-ku, Tokyo, Japan), E-AX, E-5XM (Soken Chemical & Engineering Co., Ltd., Toshima-ku, Tokyo, Japan)); and N,N'-(cyclohexane-l,3-diylbismethylene)bis(diglycidylamine) (product name: TETRAD-C (Mitsubishi Gas Chemical Company Inc., Chiyoda-ku, Tokyo, Japan), E-5C (Soken Chemical & Engineering Co., Ltd., Toshima-ku, Tokyo, Japan)). Examples of the bisamide crosslinking agent include l,r-(l,3-phenylenedicarbonyl)bis(2-methylaziridine), 1,4- bis(ethyleneiminocarbonylamino)benzene, 4,4'-bis(ethyleneiminocarbonylamino)diphenylmethane, and l,8-bis(ethyleneiminocarbonylamino)octane. Examples of the aziridine crosslinking agents include CHEMITITE PZ33 (Nippon Shokubai Co., Ltd., Osaka-shi, Osaka, Japan), and NeoCryl CX-100 (DSM Coating Resins, LLC., Zwolle, Provincie Overijssel, Netherlands). Examples of carbodiimide crosslinking agents include Carbodilite V-03, V-05, and V-07 (Nisshinbo Chemical Inc., Chuo-ku, Tokyo, Japan).

[0055] An amount of the crosslinking agent used can be about 0.01 parts by mass or more, about 0.05 parts by mass or more, or about 0. 1 parts by mass or more, and about 5 parts by mass or less, about 3 parts by mass or less, or about 2 parts by mass or less, relative to 100 parts by mass of the first copolymer including a constituent unit derived from a carboxyl group-containing monomer.

[0056] By changing a blending ratio of the first copolymer including a constituent unit derived from a carboxyl group-containing monomer and the second copolymer including a constituent unit derived from an amino group-containing monomer, desired performance (for example, adhesive force, heat shrinkage resistance, reworkability, and followability) can be imparted to the laminate. In one embodiment, the blending ratio of the second copolymer is less than about 20 parts by mass, about 15 parts by mass or less, about 10 parts by mass or less, or about 7 parts by mass or less, and is about 1 part by mass or more, about 2 parts by mass or more, or about 3 parts by mass or more relative to 100 parts by mass of the first copolymer. The adhesive layer containing the second copolymer in such a ratio can improve performance such as adhesive force, heat shrinkage resistance, reworkability, and followability. The first copolymer having a weight average molecular weight of about 800,000 or less has a molecular weight lower than that of a known copolymer and is easily wetted, so that it has been difficult to obtain significant performance in terms of re workability. Under such circumstances, the present inventor has found that the wettability is changed only by blending the second copolymer in a low amount, and the reworkability can be unexpectedly improved.

[0057] A total content of the first copolymer, the second copolymer, and an optional third copolymer described later in the adhesive layer or the adhesive composition (solid content) can be, for example, about 25 mass% or more, about 30 mass% or more, about 35 mass% or more, about 40 mass% or more, about 45 mass% or more, about 50 mass% or more, about 55 mass% or more, or about 60 mass% ormore, and 100 mass% or less, about 95 mass% or less, about 90 mass% or less, or about 80 mass% or less.

[0058] The adhesive composition for forming an adhesive layer may optionally contain other components alone or in combination of two or more as long as the effects of the present disclosure are not adversely affected. Examples of such optional components can include other resins (for example, thermoplastic resins and the third copolymer described later) other than the first and second copolymers described above, fillers, conductive agents, thermal conductivity imparting agents, antioxidants, UV absorbing agents, light stabilizers, heat stabilizers, dispersants, plasticizers, lubricants, surfactants, leveling agents, silane coupling agents, catalysts, pigments, dyes, and solvents.

[0059] The adhesive layer of the present disclosure can be obtained, for example, by applying an adhesive composition containing the first and second copolymers (partial polymers) and a crosslinking agent to a substrate or a release liner described later, followed by a heat treatment and / or a radiation (for example, ultraviolet ray) irradiation treatment. Here, as the component used in the adhesive composition, a component that can be used in the adhesive layer described above can be similarly employed. As described above, the adhesive composition can be, for example, a solvent-type, an emulsion-type, a pressure-sensitive type, a heat-sensitive type, a heat-curable type, or a radiation (e.g., ultraviolet) curable type adhesive composition.

[0060] The heat treatment can be performed using, for example, a heater such as an infrared heater, hot air, an oven, or the like. The heat treatment can be performed batchwise or continuously using a belt conveyor or the like, but is preferably performed continuously from the viewpoint of productivity or the like. A heating temperature (set temperature) can be, for example, about 70°C or higher, about 80°C or higher, or about 90°C or higher. An upper limit of the heating temperature is not particularly limited, and can be, for example, about 160°C or lower, about 140°C or lower, or about 120°C or lower.

[0061] The ultraviolet irradiation, which is a type of radiation irradiation, can be performed using, for example, a low-pressure mercury lamp, moderate -pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, xenon lamp, metal halide lamp, electrode-free lamp, UV-LED, or the like as a light source. The ultraviolet irradiation can be performed batchwise or continuously using a belt conveyor or the like, but is preferably performed continuously from the viewpoint of productivity or the like. An irradiation dose of ultraviolet rays (UV-C) can be, for example, about 1 mJ / cm2or more, about 50 mJ / cm2or more, or about 100 mJ / cm2or more. An upper limit of the irradiation dose of ultraviolet rays is not particularly limited, and can be, for example, about 500 mJ / cm2or less or about 450 mJ / cm2or less.

[0062] The adhesive composition can typically be produced by mixing the above-described first copolymer, second copolymer, crosslinking agent, and optional components as necessary.

[0063] In some embodiments, when a pigment is added to the adhesive composition, it is preferable that (1) at least one selected from the group consisting of the second copolymer and the third copolymer including a constituent unit derived from an amide group-containing monomer is mixed with a pigment to prepare a pigment mixture, and the pigment mixture is mixed with a mixture containing the firstcopolymer and a crosslinking agent to produce the adhesive composition, or it is preferable that (2) at least one selected from the group consisting of the second copolymer and the third copolymer including a constituent unit derived from an amide group-containing monomer, a crosslinking agent, and a pigment are mixed to prepare a pigment mixture, and the pigment mixture is mixed with the first copolymer to produce the adhesive composition. By producing the adhesive composition in this manner, an adhesive composition having excellent pigment dispersibility can be obtained.

[0064] The third copolymer including a constituent unit derived from an amide group-containing monomer can be obtained by copolymerizing an amide group-containing monomer with at least one selected from the group consisting of the above-described monoethylenically unsaturated monomer, a (meth)acrylate monomer containing a biologically derived carbon atom, and a carboxy group-containing unsaturated monomer. From the viewpoint of pigment dispersibility and the like, vinyl acetate, n-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate are preferable as the monoethylenically unsaturated monomer, and (meth)acrylic acid is preferable as the carboxy group-containing unsaturated monomer. From the viewpoint of improving the performance such as the compatibility with the first copolymer and the second copolymer described above, the third copolymer preferably contains the same or the same kind of constituent unit as the constituent unit derived from the monoethylenically unsaturated monomer included in the first copolymer and / or the second copolymer.

[0065] Examples of the amide group-containing monomer include N-vinylcaprolactam, N- vinylpyrrolidone, (meth)acrylamide, N-methyl (meth)acrylamide, N,N-dimethyl (meth)acrylamide, and N-octyl (meth)acrylamide. Among them, (meth)acrylamide is preferable from the viewpoint of pigment dispersibility and the like. The amide group-containing monomers can be used alone, or two or more types thereof can be used in combination.

[0066] A proportion of the constituent unit derived from the amide group-containing monomer can be about 0.01 mass% or more, about 0.05 mass% or more, or about 0.1 mass% or more, and about 5 mass% or less, about 1 mass% or less, or about 0.5 mass% or less relative to the third copolymer.

[0067] In some embodiments, when the third copolymer does not include the biologically derived constituent unit, the proportion of the constituent unit derived from the above-described monoethylenically unsaturated monomer other than the biologically derived constituent unit can be, for example, about 85 mass% or more, about 90 mass% or more, or about 92 mass% or more, and about 99.5 mass% or less, about 99 mass% or less, or about 98 mass% or less relative to the third copolymer. When the third copolymer contains the biologically derived constituent unit, the proportion of such a constituent unit can be, for example, about 40 mass% or more, about 50 mass% or more, about 55 mass% or more, or about 60 mass% or more, and about 95 mass% or less, about 90 mass% or less, about 80 mass% or less, about 75 mass% or less, about 70 mass% or less, or about 65 mass% or less relative to the third copolymer, and when the biologically derived constituent unit is present, the proportion of the constituent unit derived from the above-described monoethylenically unsaturated monomer other than the biologically derived constituent unit can be, for example, about 10 mass% or more, about 15 mass% or more, about 20 mass% or more, about 25 mass% or more, or about 30 mass% or more, about 50 mass%or less, about 45 mass% or less, about 40 mass% or less, or about 35 mass% or less relative to the third copolymer.

[0068] In some embodiments, the proportion of the constituent unit derived from the carboxy group- containing unsaturated monomer can be about 0.5 mass% or more, about 1 mass% or more, or about 2 mass% or more, and about 15 mass% or less, about 10 mass% or less, or about 8 mass% or less relative to the third copolymer.

[0069] When the adhesive composition and the adhesive layer formed from the composition contain the third copolymer including a constituent unit derived from an amide group-containing monomer, in one embodiment, a blending ratio of the third copolymer is less than about 20 parts by mass, about 18 parts by mass or less, about 15 parts by mass or less, about 10 parts by mass or less, or about 7 parts by mass or less, and about 1 part by mass or more, about 2 parts by mass or more, or about 3 parts by mass or more, relative to 100 parts by mass of the first copolymer. The adhesive layer containing the third copolymer in such a ratio is excellent in pigment dispersibility and can improve performance such as concealing properties.

[0070] The pigment that can be blended in the adhesive layer is not particularly limited, and an inorganic pigment or an organic pigment that has been known as a pigment can be used. The pigment may be surface-treated with silicon oxide, aluminum oxide, or the like. The pigment may be used alone or in combination of two or more types.

[0071] Examples of the inorganic pigment include white pigments such as zinc carbonate, zinc oxide, zinc sulfide, and titanium dioxide (titanium oxide); colored pigments such as black iron oxide, yellow iron oxide, red iron oxide, ultramarine blue, Prussian blue, cobalt blue, titanium yellow, turquoise, and molybdenum orange; and carbon blacks such as furnace black, channel black, thermal black, and acetylene black.

[0072] Examples of the organic pigment include C.I. Pigment White 6, C.I. Pigment Black 7, C.I. Pigment Red 122, 202, 254, and 255, C.I. Pigment Orange 43, C.I. Pigment Violet 19 and 23, C.I. Pigment Blue 15, 15: 1, 15: 2, 15: 3, and 15: 4, and C.I. Pigment Brown 23 and 25, C.I. Pigment Yellow 74, 109, 110, and 128, and C.I. Pigment Green 7 and 36.

[0073] A blending amount of the pigment can be, for example, about 0.1 mass% or more, about 1 mass% or more, or about 5 mass% or more, and about 55 mass% or less, about 50 mass% or less, about 20 mass% or less, or about 10 mass% or less relative to the entire adhesive composition (solid content) or adhesive layer.

[0074] In some embodiments, the adhesive composition of the present disclosure has a solid content of about 45% or more. The solid content of the adhesive composition can be about 48% or more, about 50% or more, about 52% or more, or about 55% or more, and can be about 80% or less, about 70% or less, about 65% or less, or about 60% or less. When an adhesive composition having a high solid content can be used, for example, energy required for drying the adhesive layer can be reduced, and as a result, it is possible to suitably contribute to an environmental problem.

[0075] A thickness of the adhesive layer of the present disclosure may be appropriately set in consideration of the 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.

[0076] The laminate of the present disclosure includes a substrate.

[0077] A material for the substrate is not particularly limited, and, for example, one type of or a blend of two or more types of (meth)acrylic resins including polymethyl methacrylate (PMMA) and (meth)acrylic copolymers, resins having a urethane bond (e.g., polyurethane), fluororesins such as ethylene-tetrafluoroethylene copolymers (ETFE), polyvinylidene fluoride (PVDF), and methyl methacrylate -vinylidene fluoride copolymers (PMMA / PVDF), silicone resins, polyvinyl chloride (PVC), polycarbonate (PC), polyolefins such as polyethylene (PE) and polypropylene (PP), polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyamides such as nylon, and copolymers such as ethylene / acrylic acid copolymers (EAA) and ionomers thereof, ethylene -ethyl acrylate copolymers, ethylene-vinyl acetate copolymers, and ethylene-vinyl alcohol copolymers (EV OH) can be used. Here, in the present disclosure, the term "resins having urethane bonds" 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.

[0078] The substrate may have a multilayer structure. For example, the substrate may be a laminate of fdms formed from the resins described above, or may be a multilayer coating of the resins described above. The substrate may have a three-dimensional uneven shape such as an embossed pattern on the entirety or part of the surface thereof.

[0079] For example, the substrate can be formed by coating the adhesive layer with a resin composition directly or via a bonding layer or a decorative layer. The substrate can be coated before or after application of the laminate to an adherend which will be described below. Alternatively, the release liner can be coated with the resin composition to form a substrate film, and the film can be laminated on the adhesive layer. For example, the substrate film can be formed by coating a release liner or the like with a resin material such as a curable (meth)acrylic resin composition or a reactive polyurethane composition by knife coating, bar coating, blade coating, doctor coating, roll coating, or cast coating, and then radiation- or heat-curing the resin material as necessary.

[0080] As the substrate, a substrate formed in a film shape in advance by extrusion, stretching, or the like may be used. Such a film can be laminated on the adhesive layer. By using a film with high flatness as such a film, an article (structure) can be given an appearance of higher surface flatness. The substrate can be formed by multilayer extrusion with another layer. For example, a (meth)acrylic film can be used as the other layer. For example, a resin containing polymethyl methacrylate (PMMA), poly(butyl acrylate), (meth)acrylic copolymer, ethylene / acrylic copolymer, ethylene vinyl acetate / acrylic copolymer can be formed into a film and used as the (meth)acrylic film. The (meth)acrylic film is excellent in transparency and / or scratch resistance, resistant to heat and / or light, and less likely to cause discolorationand / or changes in gloss. In addition, excellent molding processability is achieved without use of a plasticizer, and excellent contamination resistance is also achieved because use of plasticizer is not required. Among these, a (meth)acrylic fdm having PMMA as the main component is preferred. For example, in a case where a (meth)acrylic resin having excellent scratch resistance or the like is used as such the other layer and a fluororesin having excellent chemical resistance or the like, such as ETFE, PVDF, or PMMA / PVDF, is used as the substrate, the formed substrate can be a substrate having performances of both the layers.

[0081] The substrate of the present disclosure may contain an optional component as long as the performance (for example, protective performance and decorativeness) according to the application is not hindered. Examples of the optional component include fdlers, antioxidants, UV absorbing agents, light stabilizers, heat stabilizers, hard coat agents, gloss imparting agents, dispersants, plasticizers, flow improvers, surfactants, leveling agents, silane coupling agents, catalysts, pigments, and dyes. Among these, for example, use of UV absorbing agents such as benzotriazole, Tinuvin (trademark) 400 (available from BASF), and hindered amine light stabilizers (HALS) such as Tinuvin (trademark) 292 (available from BASF) can effectively prevent discoloration, fading, and deterioration of the adhesive layer located as a lower layer. The hard coat agent may be contained in the substrate, or may be applied as a hard coat layer by separately applying a coating onto the substrate. The optional components can be used alone, or in combination of two or more types thereof.

[0082] The substrate may be partially translucent or opaque. However, when the laminate includes, for example, a decorative layer or the like, the substrate is preferably transparent from the viewpoint of visibility of such a layer and the like.

[0083] A thickness of the substrate may vary, and may be, for example, about 1 micrometer or more, about 5 micrometers or more, about 10 micrometers or more, about 30 micrometers or more, or about 50 micrometers or more, and may be about 200 micrometers or less, about 150 micrometers or less, about 100 micrometers or less, or about 90 micrometers or less.

[0084] In some embodiments, the laminate of the present disclosure optionally includes an additional layer. Examples of such an additional layer can include at least one selected from the group consisting of decorative layers (e.g., color layers, pattern layers, and relief layers), brightening layers, bonding layers, middle fdm layers, and release liners. The additional layer may be applied to the entire surface or a part of the surface of the laminate. The additional layer may have a three-dimensional shape such as an emboss pattern on its surface. A laminate including a layer capable of exhibiting decorative properties (e.g., a decorative layer) can also be referred to as "decorative laminate". In the case of exhibiting protective performance, for example, performance capable of preventing chipping due to pebbles or the like, it can also be referred to as "protective laminate".

[0085] 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 strong 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 picture pattern, or the like to an article; a relief(embossed patern) layer in which an uneven shape is provided on the surface; and combinations of these layers.

[0086] The decorative layer can be applied to, but not limited to, the entirety or part of the surface of a layer constituting the laminate, such as the substrate and / or the adhesive layer, directly or via a bonding layer.

[0087] The material for the color layer is not limited to the following, but for example, a material obtained by dispersing a pigment in a binder resin, such as a (meth)acrylic resin or a resin having a urethane bond, can be used. Examples of the pigment include inorganic pigments, such as carbon black, chrome yellow, yellow iron oxide, colcothar, or red iron oxide; or organic pigments, such as 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, and a quinacridone pigment such as quinacridone red.

[0088] The color layer can be formed using such a material, for example, by a coating method, such as gravure coating, roll coating, die coating, bar coating, or knife coating.

[0089] As a patern layer, although not limited to the following, patern layers obtained by printing a patern such as a patern, logo, or design directly on the substrate and / or the adhesive layer using a printing method such as gravure direct printing, gravure offset printing, inkjet printing, laser printing, or screen printing may be employed, or a fdm, sheet, or the like having a patern, logo, design, or the like formed by coating such as gravure coating, roll coating, die coating, bar coating, or knife coating, punching, etching, or the like also can be used. For example, a material similar to those used in the color layer can be used for the patern layer.

[0090] For the relief layer, a thermoplastic resin fdm having an uneven shape on the surface may be used, the uneven shape being obtained by a well-known method in the art, such as, for example, emboss finishing, scratch processing, laser processing, dry etching processing, or hot press processing. The relief layer may be also formed by applying a thermoseting or radiation-curable resin, such as a curable (meth)acrylic resin, on a release liner having an uneven shape, curing the resin by heat or radiation, and removing the release liner.

[0091] The thermoplastic resin, thermoseting resin, and radiation-curable resin used in the relief layer are not particularly limited but, for example, a fluororesin, 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.

[0092] The decorative layer of the present disclosure can contain, for example, fillers, reinforcing agents, antioxidants, UV absorbing agents, light stabilizers, heat stabilizers, dispersants, plasticizers, flow improvers, surfactants, leveling agents, silane coupling agents, and catalysts as optional components in a range that does not negatively affect the effect of the present disclosure.

[0093] A thickness of the decorative layer may be appropriately adjusted according to the required decorativeness or the like and is not particularly limited. 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.

[0094] Examples of the brightening layer may include, but are not limited to, layers constituting the laminate, for example, layers containing a metal selected from aluminum, nickel, gold, silver, copper, platinum, chromium, iron, tin, indium, titanium, lead, zinc, and germanium, or an alloy or compound thereof, formed by vacuum deposition, sputtering, ion plating, plating, or the like on the entire surface or a part of the substrate and / or the adhesive layer. The thickness of the brightening layer may be appropriately set in accordance with the required decorativeness and the like.

[0095] In the laminate of the present disclosure, a bonding layer (sometimes referred to as "primer layer", for example) can be used to bond an additional layer in the laminate. As the bonding layer, a generally used adhesive agent such as a solvent-type, emulsion-type, pressure-sensitive type, heatsensitive type, and heat-curable or ultraviolet-curable type adhesive agent, including (meth)acrylics, polyolefins, polyurethanes, polyesters, rubbers, and the like can be used. The bonding layer may be applied by a well-known coating method or the like.

[0096] The laminate of the present disclosure may include a middle film layer. As the middle film layer, for example, resin films of resins having a urethane bond, polyvinyl chlorides, polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, (meth)acrylic polymers, or fluorochemical polymers can be used.

[0097] A thickness of the middle film layer can be, for example, 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.

[0098] In 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.

[0099] A thickness of the release liner, generally, can 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.

[0100] The laminate of the present disclosure may be, for example, a sheet-like article, a rolled body winded in a roll shape, or an article with a three-dimensional shape.

[0101] The following production method will be described as an example, but a method for producing the laminate of the present disclosure is not limited thereto.

[0102] For example, in the case of a laminate having a structure in which a release liner, an adhesive layer, a decorative layer (for example, a color layer), and a substrate are provided in this order, the substrate is coated thereon with a composition for a color layer containing a pigment, and a drying stepand a curing step are applied as necessary to form a color layer. Subsequently, an adhesive composition is coated on the color layer, and a drying step and a curing step are applied as necessary to form an adhesive layer, and then a release liner is attached to the adhesive layer, thereby making it possible to form a laminate.

[0103] In some embodiments, the above-described laminate of the present disclosure is disposed on an adherend via the adhesive layer, and an article including the laminate is provided.

[0104] A material for the adherend to which the laminate can be applied is not particularly limited. Examples of such a material include resin materials (e.g., polyolefin resins, polyester resins, (meth)acrylic resins, polycarbonate resins, resins having a urethane bond, and acrylonitrile-butadiene- styrene copolymers), inorganic materials (e.g., glass, ceramic, concrete, gypsum, calcium silicate, natural stone, and asphalt), rubber materials, cloth materials (e.g., woven fabrics, knitted fabrics, and nonwoven fabrics), metal or metal alloy materials (e.g., iron, aluminum, and stainless steel), and woody materials including paper and the like.

[0105] A shape or structure of the adherend is not particularly limited. The shape may be, for example, a plane shape (e.g., film shape or plate shape), curved surface shape, deformed shape, or three- dimensional shape, and the structure may be a single-layer structure, a laminated structure, or a composite structure in which a plurality of members having different shapes or materials are combined.

[0106] The laminate of the present disclosure can be used in a variety of applications. Examples of such purposes 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. Although at least one of the first copolymer and the second copolymer to be used includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom, the adhesive layer included in the laminate of the present disclosure is also excellent in durability such as weather resistance, and therefore can be suitably used for exterior applications, more specifically, for exterior applications of vehicles (for example, automobiles) and for exterior applications (for example, exterior wall members) of buildings. In some embodiments, the laminate of the present disclosure is also excellent in followability, and thus can be suitably used for a rough surface. For example, the laminate of the present disclosure can be suitably used on rough surfaces (e.g., wall surfaces) having irregularities with a maximum height from a protrusion to a bottom of about 1 mm or more, or about 1.5 mm or more, 1 cm or less, 7 mm or less, 5 mm or less, 3 mm or less, 2.5 mm or less, or 2 mm or less.

[0107] A method of applying the laminate of the present disclosure to the adherend (support member) constituting the article is not particularly limited, and a known method can be appropriately used. Examples of such a method can include hand application, injection molding methods such as an insert injection molding method, an in-molding method, an over-molding method, a two-color injection molding method, a core back injection molding method, and a sandwich injection molding method, a lamination method, and a three-dimensional heat stretch blow molding method (TOM).Examples

[0108] 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 is generally indicated by a significant digit that is rounded.

[0109] Table 1 shows various materials used. In the table, the "Mw" and "Tg" mean "weight average molecular weight" and "glass transition temperature", respectively. Regarding the first copolymer, the second copolymer, and the third copolymer, each monomer component, a chain transfer agent (such as isooctylthioglycolate), a polymerization initiator (such as 2,2'-azobis (2,4-dimethylvaleronitrile)), and a solvent (such as ethyl acetate) were mixed so as to have a mass ratio of a constituent unit derived from the monomer (for example, NOAA: n-octyl acrylate, BA: n- butyl acrylate, or AA: acrylic acid) described in the table, and the resulting polymerizable composition was polymerized by a known polymerization method to prepare each copolymer-containing solution. Here, NOAA (n-octyl acrylate) and 2OA (2 -octyl acrylate) correspond to (meth)acrylate monomer containing a biologically derived carbon atom.

[0110] Table 1A: n-butyl acrylate, AA: acrylic acid, 2EHA: 2-ethylhexyl acrylate, MMA: methyl methacrylate, BMA: n-butyl methacrylate, DMAEMA: 2-(dimethylamino)ethyl methacrylate OAA: n-octyl acrylate, 2OA: 2-octyl acrylate, Vac: vinyl acetate, ACM: acrylamide

[0111] Test Example 1In Test Example 1, the adhesive force, heat shrinkage resistance, and reworkability of an adhesive layer containing no pigment were evaluated.

[0112] Example 1An adhesive composition was prepared by mixing the first copolymer (ADH1) including a constituent unit derived from a carboxyl group-containing monomer, the second copolymer (HP1) including a constituent unit derived from an amino group-containing monomer, and the crosslinking agent (TETRAD (trademark) -X) such that a mass ratio of the first copolymer (ADH1), the second copolymer (HP1), and the crosslinking agent (TETRAD (trademark) -X) was 100: 5: 0.18 based on a nonvolatile component. The adhesive composition was applied onto a release liner (SCW1034) with a knife coater. The resulting adhesive layer was dried at 95°C for 5 minutes to obtain a 40 micrometer-thick adhesive layer. A substrate (UW5002) was laminated on the adhesive layer to obtain a test sample of Example 1.

[0113] Examples 2 to 10Test samples of Examples 2 to 10 were obtained in the same manner as in Example 1 except that at least one of the first copolymer, the thickness of the adhesive layer, and the substrate was changed as shown in Table 2.

[0114] Reference Examples 1 to 2Test samples of Reference Examples 1 to 2 were obtained in the same manner as in Example 1 except that at least one of the first copolymer, the thickness of the adhesive layer, and the substrate was changed as shown in Table 2. Here, in Reference Examples 1 to 2, a test sample including an adhesive layer prepared using a known petroleum -derived material was employed.

[0115] Evaluation test 1Each of the obtained test samples was evaluated according to the following test method. The results are indicated in Table 2.

[0116] Adhesive force test 1: Adhesive force to coated plateA test piece was prepared by cutting a test sample into a width of 25 mm and a length of 150 mm. The test piece was applied to a melamine-coated plate (available from PALTEK CORPORATION (Hiratsuka-shi, Kanagawa, Japan)) under an atmosphere of 20°C according to JIS Z 0237 8.2.3. The test piece was left standing at 20°C for 48 hours, and then a 180 degree peel strength of the test piece was measured using a Tensilon universal material testing machine (available from A&D Company, Limited (Toshima-ku, Tokyo, Japan)). A speed of an air jaw was 300 mm per minute.

[0117] Adhesive force test 2: Adhesive force to aluminum plateA test piece was prepared by cutting a test sample into a width of 25 mm and a length of 150 mm. The test piece was applied to an aluminum plate under an atmosphere of 20°C according to JIS Z 0237 8.2.3. The test piece was left standing at 20°C for 48 hours, and then a 180 degree peel strength of the test piece was measured using a Tensilon universal material testing machine (available from A&D Company, Limited (Toshima-ku, Tokyo, Japan)). The speed of the air jaw was 300 mm per minute.

[0118] Heat shrinkage testA test piece was prepared by cutting a test sample into a width of 50 mm and a length of 100 mm. This test piece was attached to an aluminum plate and set at 23 °C for 24 hours, and then the test piece was cut into a cross shape. The test piece was left standing at 65°C for 48 hours. After heat aging, the value of the maximum width of the opening (mouth opening) of the cut was measured with a microscope.

[0119] Reworkability testA test piece was prepared by cutting a test sample into a width of 210 mm and a length of 300 mm. The test piece was applied to a melamine-coated plate (available from PALTEK CORPORATION (Hiratsuka-shi, Kanagawa, Japan)) with a squeegee under an atmosphere of 25°C, and then quickly peeled off by hand. The test piece that was easily peeled off without being stretched was evaluated as “Good”, the test piece that was not stretched and felt heavy to be peeled off was evaluated as “Acceptable”, and the test piece that had a strong tack, was hard to peel off, and was stretched was evaluated as “Poor”.

[0120] Table 2

[0121] Test Example 2In Test Example 2, an adhesive layer containing a pigment was evaluated for the concealing properties, the tensile strength, the elongation properties, the followability, and the gloss retention in addition to evaluation of the adhesive force, the heat shrinkage resistance, and the re workability.

[0122] Table 3 shows the pigment mixture used in preparing the adhesive composition containing the pigment, and Table 4 shows each component amount (parts by mass) and the solid content (%) of the adhesive composition prepared using such a pigment mixture. Here, each component amount in Table 4 is a value based on the nonvolatile content.

[0123] Table 3MEK: methyl ethyl ketone, EtAc: ethyl acetate0124] Table 4

[0125] Example 11The adhesive composition (CAI) in Table 4 was applied onto a release liner (SLK-110AWP#3009) with a knife coater. The resulting white adhesive layer was dried at 95°C for 5 minutes to obtain a 39 micrometer-thick adhesive layer. A substrate (UW5002) was laminated on the adhesive layer to obtain a test sample of Example 11.

[0126] Examples 12 to 18Test samples of Examples 12 to 18 were obtained in the same manner as in Example 11 except that at least one of the adhesive composition, the thickness of the adhesive layer, and the substrate was changed as shown in Table 5.

[0127] Reference Examples 3 to 6Test samples of Reference Examples 3 to 6 were obtained in the same manner as in Example 11 except that at least one of the adhesive composition, the thickness of the adhesive layer, and the substrate was changed as shown in Table 5. Here, in Reference Examples 3 to 6, a test sample including an adhesive layer prepared using a known petroleum-derived material was employed.

[0128] Evaluation test 2Each of the obtained test samples was evaluated according to the following test method. The results are indicated in Table 5. Here, the test method performed in Evaluation Test 1 described above was similarly adopted for the test regarding the adhesive force to a coated plate, the adhesive force to an aluminum plate, the heat shrinkability, and the reworkability.

[0129] Concealing property testA test sample was cut into a 100 mm x 50 mm square to prepare a test piece. The test piece was attached to a “concealing power chart sheet” (zebra pattern). L*, a*, and b* values in a white region and a black region were measured using a spectrophotometer (CM-3700d, available from Konica Minolta, Inc. (Chiyoda-ku, Tokyo, Japan)). The values in the white region were set to Li*, af, and bi*, and the values in the black region were set to L2*, a2*, and b2*. A color difference (AE) was calculated from the following formula 1 :AEbf)2> • • Formula 1Here, a sample having a color difference of less than 6 in the black region and the white region was evaluated as “A”, a sample having a color difference of 6 or more and less than 12 was evaluated as “B”, and a sample having a color difference of 12 or more was evaluated as “C” The “A” and “B” evaluations were defined as acceptable levels.

[0130] Yield point evaluation testA test piece was prepared by cutting a test sample into a width of 25 mm and a length of 150 mm. Under an atmosphere of 20°C, the tensile force and elongation of the test piece were measured using a Tensilon universal material testing machine (available from A&D Company, Limited (Toshima-ku, Tokyo, Japan)). The speed of the air jaw was 300 mm per minute, and an air jaw interval was 100 mm. The yield point was determined from a graph of the elongation (x-axis) and the tensile force (y-axis).

[0131] Elongation te stA test piece was prepared by cutting a test sample into a width of 25 mm and a length of 150 mm. Under an atmosphere of 20°C, the elongation of the test piece was measured using a Tensilon universal material testing machine (available from A&D Company, Limited (Toshima-ku, Tokyo, Japan)). The speed of the air jaw was 300 mm per minute, and the air jaw interval was 100 mm.

[0132] Tensile strength testA test piece was prepared by cutting a test sample into a width of 25 mm and a length of 150 mm. Under an atmosphere of 20°C, the tensile force and elongation of the test piece were measured using a Tensilon universal material testing machine (available from A&D Company, Limited (Toshima-ku, Tokyo,Japan)). The speed of the air jaw was 300 mm per minute, and the air jaw interval was 100 mm. The tensile force at 2% elongation was recorded as the tensile strength (2% tensile strength).

[0133] Followability testA test piece was prepared by cutting a test sample into a width of 70 mm and a length of 75 mm. Under an atmosphere of 25 °C, a test piece provided with a pre-mask was attached to a “stucco” painted finishing substrate (available from Test Materials Co., Ltd. (Kawaguchi-shi, Saitama, Japan)). The premask was peeled off, and the test piece was pressed without heating using a rivet brush "PFA-1" (available from 3M Japan Ltd. (Shinagawa-ku, Tokyo, Japan)). The pressing was performed three times back and forth on the test piece. Here, relative to a rough surface of the substrate, maximum roughness between a top and a bottom was about 1.5 mm. After attachment of the test piece, followability to the roughened substrate was visually determined. A sample having good followability to the roughened substrate was evaluated as “Good”, and a sample having insufficient followability to the roughened substrate was evaluated as “Poor”.

[0134] Gloss retention evaluation testA test piece was prepared in the same manner as in the followability test. The test piece was left standing in an oven at 65°C for 48 hours. An initial gloss value and a gloss value after aging at 65°C were measured using a portable gloss meter (GMX-202, available from MURAKAMI COLOR RESEARCH LABORATORY CO., LTD. (Chuo-ku, Tokyo, Japan)), and the gloss retention was calculated from the following formula 2:Gloss retention (%) = gloss value after aging at 65 °C / initial gloss value x 100 ... formula 2 Here, the number of repetitions was three, and an average value was recorded as a representative value. The test piece having a gloss retention of less than 200% was evaluated as “good”, and the test piece having a gloss retention of 200% or more was evaluated as “poor”.

[0135] Table 5

[0136] 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. In addition, 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.

[0137] Reference Signs List10 Substrate20 Adhesive layer30 Release liner100 Laminate

Claims

ClaimsClaim 1A laminate comprising: an adhesive layer including a first copolymer including a constituent unit derived from a carboxyl group-containing monomer, a second copolymer including a constituent unit derived from an amino group- containing monomer, and a cured product of a crosslinking agent; and a substrate, wherein the first copolymer has a weight average molecular weight of 800,000 or less and a glass transition temperature of lower than 0°C, the second copolymer has a weight average molecular weight of 30,000 or more and 100,000 or less and a glass transition temperature of 0°C or higher, and at least one of the first copolymer and the second copolymer includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom.Claim 2The laminate according to claim 1, wherein the first copolymer and the second copolymer have a molecular weight distribution of 10 or less.Claim 3The laminate according to claim 1 or 2, wherein the (meth)acrylate monomer has an alkyl group having 4 or more and 12 or less carbon atoms.Claim 4The laminate according to claim 1 or 2, wherein the (meth)acrylate monomer includes at least one selected from the group consisting of n-octyl (meth)acrylate and 2-octyl (meth)acrylate.Claim 5The laminate according to claim 1 or 2, wherein a proportion of the constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom is 40 mass% or more relative to the copolymer including the constituent unit.Claim 6The laminate according to claim 1 or 2, wherein a content of the second copolymer is 1 part by mass or more and less than 20 parts by mass relative to 100 parts by mass of the first copolymer.Claim 7The laminate according to claim 1 or 2, wherein the adhesive layer further includes a pigment.Claim 8An adhesive composition comprising: a first copolymer including a constituent unit derived from a carboxyl group-containing monomer; a second copolymer including a constituent unit derived from an amino group-containing monomer; and a crosslinking agent, wherein the first copolymer has a weight average molecular weight of 800,000 or less and a glass transition temperature of lower than 0°C, the second copolymer has a weight average molecular weight of 30,000 or more and 100,000 or less and a glass transition temperature of 0°C or higher, and at least one of the first copolymer and the second copolymer includes a constituent unit derived from a (meth)acrylate monomer containing a biologically derived carbon atom.Claim 9The adhesive composition according to claim 8, wherein the first copolymer and the second copolymer have a molecular weight distribution of 10 or less.Claim 10The adhesive composition according to claim 8 or 9, wherein the adhesive composition has a solid content of 45% or more.Claim 11The adhesive composition according to claim 8 or 9, further comprising a pigment.Claim 12A method for producing the adhesive composition according to claim 8 or 9, the production method comprising mixing the first copolymer, the second copolymer, and the crosslinking agent.Claim 13A method for producing the adhesive composition according to claim 11, the production method comprising mixing at least one selected from the group consisting of the second copolymer and a third copolymer including a constituent unit derived from an amide group-containing monomer with the pigment to prepare a pigment mixture, and mixing the pigment mixture with a mixture containing the first copolymer and the crosslinking agent, or mixing at least one selected from the group consisting of the second copolymer and the third copolymer including a constituent unit derived from an amide group- containing monomer, the crosslinking agent, and the pigment to prepare a pigment mixture, and mixing the pigment mixture with the first copolymer.

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