Layered body, method for producing same, and molded article

Abstract

This layered body comprises, in order, a substrate layer (A), an adhesive layer (B), and a resin layer (D) containing a poly(3-hydroxyalkanoate)-based copolymer (C). The glass transition temperature of the entire resin contained in the adhesive layer (B) is 20°C or greater but less than 90°C. The adhesive layer (B) has a basis weight of 0.1 g / m2 or greater but less than 5.0 g / m2. The resin layer (D) has a thickness of 5 μm to 100 μm.

Description

Laminate, manufacturing method thereof, and molded product

[0001] The present invention relates to a laminate in which a resin layer is laminated on at least one surface of a base layer such as paper, a method for producing the same, and a molded product thereof.

[0002] In recent years, environmental problems caused by discarded plastics have been attracting attention. In particular, marine pollution caused by discarded plastics is serious, and there are high hopes for the widespread use of biodegradable plastics that decompose in the natural environment.

[0003] Various biodegradable plastics are known, including poly(3-hydroxyalkanoate) copolymers (hereinafter sometimes referred to as "P3HA"). These thermoplastic polyesters are produced and accumulated as energy storage materials within the cells of many microbial species. They are biodegradable not only in soil but also in seawater. Therefore, they have attracted attention as a material that can solve the above-mentioned problems. Among these, PHBH / paper composites, which integrate a poly(3-hydroxyalkanoate) copolymer, a copolymer of 3-hydroxybutyrate (hereinafter sometimes referred to as "3HB") and 3-hydroxyhexanoate (hereinafter sometimes referred to as "3HH") (hereinafter sometimes referred to as "PHBH"), with a substrate such as paper, have attracted particular attention due to their potential application in environmentally friendly food contact containers.

[0004] Methods for integrating PHBH and paper include extrusion lamination and aqueous slurry coating. However, extrusion lamination is preferred because coating methods tend to fail to provide sufficient mechanical strength for the resin layer. However, because PHBH generally has a high melt viscosity and poor adhesion to paper, it has not been easy to bond melt-extruded PHBH and paper with sufficient strength. As a result, during the manufacturing process of cup-shaped products such as beverage cups, the laminate layer can peel off from the paper, causing problems such as leakage of contents when filled.

[0005] Patent Document 1 does not disclose PHBH, but it describes a method of applying a polycaprolactone dispersion or emulsion to paper at a rate of 10 g / m² in order to improve the penetration of biodegradable resin into paper and thereby improve laminate strength. ２ This method involves applying a coating of the film at a basis weight (dry weight of the layer) of 1000 ppm, drying it, and then laminating 3-hydroxybutyric acid / 3-hydroxyvaleric acid copolymer (PHBV) by extrusion lamination.

[0006] Japanese Patent Application Publication No. 6-293113

[0007] According to the method of Patent Document 1, the adhesion between the paper and the resin layer tends to be improved, but the polycaprolactone dispersion or emulsion is used at a concentration of 10 g / m ２ Since the paper is applied at such a large basis weight and then dried, the drying process takes a long time, resulting in low productivity. In addition, there are problems such as deterioration of the paper substrate due to the drying process, or the paper drying out too much, causing warping of the laminate.

[0008] To facilitate drying, the adhesive layer has a weight of 10 g / m ２ Although there are methods for reducing the amount of resin, in such cases there is a problem that the adhesion between the paper substrate and the resin layer becomes insufficient.

[0009] In view of the above-described current situation, an object of the present invention is to provide a laminate comprising, in this order, a base layer, an adhesive layer, and a resin layer containing a poly(3-hydroxyalkanoate)-based copolymer, which has good drying properties when the adhesive layer is formed, and has high adhesive strength between the base layer and the resin layer.

[0010] As a result of intensive research to solve the above-mentioned problems, the present inventors have found that in a laminate comprising, in this order, a base material layer, an adhesive layer, and a resin layer containing a poly(3-hydroxyalkanoate)-based copolymer, the above-mentioned problems can be solved by adjusting the glass transition temperature of the entire resin contained in the adhesive layer to be within a specific range and setting the thickness of the resin layer to be within a specific range while making the basis weight of the adhesive layer sufficiently small, and have thus completed the present invention.

[0011] That is, the present invention provides a laminate comprising, in this order, a substrate layer (A), an adhesive layer (B), and a resin layer (D) containing a poly(3-hydroxyalkanoate)-based copolymer (C), wherein the glass transition temperature of the entire resin contained in the adhesive layer (B) is 20°C or higher and lower than 90°C, and the adhesive layer (B) has a basis weight of 0.1 g / m ２ 5.0g / m or more ２ The present invention also relates to a method for producing the laminate, the method comprising the steps of: forming the adhesive layer (B) on at least one surface of the base layer (A); and forming the resin layer (D) on a surface of the adhesive layer (B) by extrusion lamination or thermal lamination. The present invention also relates to a molded article comprising the laminate.

[0012] According to the present invention, there is provided a laminate comprising, in this order, a base layer, an adhesive layer, and a resin layer containing a poly(3-hydroxyalkanoate) copolymer, which exhibits good drying properties when the adhesive layer is formed and has high adhesive strength between the base layer and the resin layer. Use of this laminate can improve the production efficiency and quality of molded articles.

[0013] 1 is a schematic diagram illustrating a stack structure of a stack according to an embodiment of the present invention.

[0014] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0015] [Laminate] A laminate according to one embodiment of the present invention has an adhesive layer (B) and a resin layer (D) containing a poly(3-hydroxyalkanoate) copolymer (C) on at least one surface of a substrate layer (A). As shown in Fig. 1, in the laminate 1, the substrate layer (A) denoted by reference numeral 2, the adhesive layer (B) denoted by reference numeral 3, and the resin layer (D) denoted by reference numeral 4 are laminated in this order.

[0016] The adhesive layer (B) may be laminated directly on the base layer (A), or another layer may be further included between the adhesive layer (B) and the base layer (A) as long as the adhesiveness is not impaired.

[0017] The resin layer (D) may be the outermost layer exposed on the surface of the laminate, or another layer may be laminated on the resin layer (D) for the purpose of imparting water resistance or gloss, etc.

[0018] The adhesive layer (B) and the resin layer (D) may be provided on only one side of the base layer (A), or the adhesive layer (B) and the resin layer (D) may be provided on each of both sides of the base layer (A). When the adhesive layer (B) and the resin layer (D) are provided on only one side of the base layer (A), no other layer may be formed on the other side, and the base layer (A) may be the outermost layer exposed on the surface of the laminate, or another layer may be laminated thereon for the purpose of imparting water resistance, gloss, or adhesiveness, etc.

[0019] When the substrate layer (A) has an adhesive layer (B) and a resin layer (D) on each side, the materials constituting the adhesive layer (B) on the front side and the adhesive layer (B) on the back side, the basis weight and thickness may be the same or different. The same applies to the resin layer (D) on the front side and the resin layer (D) on the back side. In this application, the basis weight (g / m ２ ) refers to the dry weight (solids content) of the layer.

[0020] [Substrate layer (A)] The material constituting the substrate layer (A) is not particularly limited, but is preferably biodegradable. Examples include paper (mainly composed of cellulose), cellophane, cellulose ester; polyvinyl alcohol, polyamino acid, polyglycolic acid, pullulan, or a substrate of any of these on which an inorganic material such as aluminum or silica is vapor-deposited. Among these, paper is preferred because it has excellent heat resistance and is inexpensive.

[0021] The type of paper is not particularly limited and can be appropriately selected depending on the application of the laminate, and examples include cup base paper, kraft paper, fine paper, coated paper, tissue paper, glassine paper, paperboard, etc. If necessary, a water-resistant agent, a water-repellent agent, an inorganic substance, etc. may be added to the paper, and the paper may be subjected to a surface treatment such as an oxygen barrier layer coating or a water vapor barrier coating.

[0022] The substrate layer (A) may also be subjected to a surface treatment such as corona treatment, ozone treatment, plasma treatment, frame treatment, anchor coat treatment, oxygen barrier layer coating, water vapor barrier coating, etc. These surface treatments may be performed alone or in combination.

[0023] [Adhesive Layer (B)] The adhesive layer (B) is a layer composed primarily of a resin. The main resin contained in the adhesive layer (B) is not particularly limited, but resins commonly used in the fields of coated paper or resin films can be suitably used. Resins that have a high affinity with substrates such as paper and with P3HA are preferred, and examples of such resins include acrylic resins, vinyl chloride resins, styrene-acrylic resins, styrene-butadiene resins, styrene-isoprene resins, polycarbonate resins, urea resins, melamine resins, epoxy resins, phenolic resins, urethane resins, diallyl phthalate resins, and imine resins. These resins can be used alone, or two or more resins can be mixed in any ratio.

[0024] In particular, the adhesive layer (B) preferably contains at least one of an acrylic resin and a styrene-acrylic resin, since these have excellent affinity with P3HA.

[0025] The adhesive layer (B) preferably contains the above-mentioned main resins in a total amount of 50% by weight or more, more preferably 60% by weight or more, even more preferably 70% by weight or more, and particularly preferably 80% by weight or more of the total amount of the adhesive layer (B). The upper limit may be 100% by weight or less, and may be 99% by weight or less.

[0026] When the adhesive layer (B) contains either an acrylic resin or a styrene-acrylic resin, the proportion of styrene units in the entire acrylic resin or styrene-acrylic resin is preferably 0 mol% or more and less than 50 mol%. If the styrene unit content is less than 50 mol%, it is easy to adjust the glass transition temperature (hereinafter sometimes referred to as "Tg") of the resin to less than 90°C, and the affinity between the adhesive layer (B) and P3HA is improved, thereby further improving the adhesive strength of the laminate. The proportion of the styrene units is more preferably 40 mol% or less, even more preferably 30 mol% or less, and particularly preferably 20 mol% or less.

[0027] Furthermore, when the adhesive layer (B) contains either an acrylic resin or a styrene-acrylic resin, the proportion of methyl methacrylate (hereinafter sometimes referred to as "MMA") units in the (meth)acrylic units contained in the entire acrylic resin or styrene-acrylic resin is preferably 50 mol% or more and less than 95 mol%. The (meth)acrylic units refer to the acrylic monomer units and methacrylic monomer units that constitute the resin. When the proportion of MMA units is 50 mol% or more, the Tg of the resin can be easily adjusted to 20°C or higher, and the adhesive strength of the laminate can be further improved. The proportion of MMA units is more preferably 60 mol% or more, even more preferably 70 mol% or more, and particularly preferably 80 mol% or more. On the other hand, when the proportion of MMA units is less than 95 mol%, the Tg of the resin can be easily adjusted to less than 90°C, and the adhesive strength of the laminate can be improved.

[0028] The monomer components of the structural units other than the styrene unit and the MMA unit contained in the acrylic resin or the styrene-acrylic resin are not particularly limited, but are preferably monomer components having good affinity with P3HA, and specific examples thereof include acrylic acid, methacrylic acid, acrylic acid esters, and methacrylic acid esters.

[0029] From the viewpoint of maintaining the Tg of the resin within an appropriate range, it is preferable to use methacrylic acid and / or a methacrylic acid ester, and it is particularly preferable to use methacrylic acid and a methacrylic acid ester in combination.

[0030] Specific examples of methacrylic acid esters other than MMA include alkyl methacrylate esters such as ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, tertiary butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, alkyl methacrylate, stearyl methacrylate, and cyclohexyl methacrylate; phenyl methacrylate, benzyl methacrylate, isobornyl methacrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, allyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-methoxyethyl methacrylate, and 2-ethoxyethyl methacrylate. These may be used alone or in combination of two or more types as necessary.

[0031] The Tg of the main resin contained in the adhesive layer (B) is not particularly limited, but is preferably within a range that satisfies the Tg (described below) of all the resins contained in the adhesive layer (B). From this viewpoint, the Tg of the main resin contained in the adhesive layer (B) is preferably 20° C. or higher and lower than 90° C., more preferably 25° C. or higher and lower than 85° C., and even more preferably 30° C. or higher and lower than 80° C.

[0032] The main resin contained in the adhesive layer (B) may be water-soluble or soluble in an organic solvent. When using a water-insoluble resin, other additives may be added to improve dispersibility in water and coatability. When coating an aqueous emulsion, aqueous slurry, or water-soluble resin, the solids concentration of the resin is not particularly limited, but is preferably 30% by weight or more, more preferably 40% by weight or more, and even more preferably 50% by weight or more in order to reduce the amount of heat required for drying. Furthermore, from the viewpoint of avoiding sedimentation of the dispersed resin and achieving good coatability, the solids concentration is preferably 60% by weight or less.

[0033] The adhesive layer (B) may contain only the main resin as a resin component, or may contain a tackifying resin in addition to the main resin. By using a tackifying resin, the Tg of the entire resin contained in the adhesive layer (B) can be reduced, and the adhesive strength of the laminate can be further improved.

[0034] The tackifying resin is not particularly limited, and commonly used resins can be used. They may be either solid or liquid at room temperature. Specifically, rosin-based resins, terpene-based resins, ethylene-based resins, vinyl acetate-based resins, alkylphenol-formaldehyde-based resins, alkylphenol-acetylene-based resins, coumarone-indene-based resins, styrene-based resins, and xylene-formaldehyde-based resins can be preferably used. These may be used alone or in combination of two or more. Rosin-based resins are particularly preferred.

[0035] The weight average molecular weight (Mw) of the tackifying resin can be appropriately selected, but from the viewpoint of the adhesive strength improving effect, it is preferably 100 or more and less than 5,000, more preferably 200 or more and 3,000 or less, even more preferably 300 to 2,000, and particularly preferably 400 to 1,000.

[0036] The weight-average molecular weight of the tackifying resin can be measured in terms of polystyrene using gel permeation chromatography (HPLC GPC system manufactured by Shimadzu Corporation) using a chloroform solution. As a column for the gel permeation chromatography, a column appropriate for measuring the weight-average molecular weight may be used.

[0037] When the adhesive layer (B) contains a tackifying resin, the content of the tackifying resin is preferably 1 wt % or more but less than 30 wt %, more preferably 3 to 25 wt %, and even more preferably 5 to 20 wt %, of the total weight of the adhesive layer (B), from the viewpoint of improving adhesive strength. In particular, when the content of the tackifying resin is 10 wt % or more, the adhesive strength of the laminate can be particularly good.

[0038] The Tg of the entire resin contained in the adhesive layer (B) is controlled to be in the range of 20° C. or higher and lower than 90° C. from the viewpoint of ensuring the adhesive strength between the base material layer (A) and the resin layer (D). If the Tg of the entire resin contained in the adhesive layer (B) is lower than 20° C., the adhesive strength may be insufficient due to strong adhesion at around room temperature. On the other hand, if the Tg is higher than 90° C., the amount of heat may be insufficient depending on the resin temperature when laminating the resin layer (D), resulting in insufficient laminate strength.

[0039] The Tg of the entire resin contained in the adhesive layer (B) is preferably 25° C. or higher and lower than 85° C., more preferably 30° C. or higher and lower than 80° C. The upper limit may be 75° C. or lower, 70° C. or lower, or 65° C. The lower limit may be 40° C. or higher, 50° C. or higher, or 60° C. or higher.

[0040] In addition, the Tg of the entire resin contained in the adhesive layer (B) refers to the Tg of the main resin when the adhesive layer (B) contains only the main resin as a resin component, and refers to the Tg of the main resin and the tackifier resin as a whole when the adhesive layer (B) contains the main resin and the tackifier resin.

[0041] The Tg of the entire resin contained in the adhesive layer (B) can be measured by differential thermal analysis.

[0042] In the laminate according to this embodiment, the basis weight of the adhesive layer (B) is 0.1 g / m ２ 5.0g / m or more ２ The weight is adjusted to a range of less than 0.1 g / m ２ If the amount is less than 5.0 g / m, the adhesiveness to the resin layer (D) may decrease. ２ If the weight per unit area exceeds 0.5 g / m, a large amount of heat is required during drying, which increases the load on the equipment, and for example, insufficient drying may cause problems such as blocking during winding of the raw web. ２ 4.0g / m or more ２ Preferably, the content is 0.8 g / m or less. ２ 3.0g / m or more ２ More preferably, 1.0 g / m or less ２ 2.5g / m or more２ The following is even more preferred:

[0043] [Resin Layer (D)] The resin layer (D) contains a poly(3-hydroxyalkanoate) copolymer (hereinafter, sometimes referred to as "P3HA") (C). The resin layer (D) may be the outermost layer in the laminate according to this embodiment. In this case, the resin layer (D) can be used for heat sealing (described below).

[0044] The poly(3-hydroxyalkanoate) copolymer (C) is a biodegradable aliphatic polyester (preferably a polyester containing no aromatic ring) and is a copolymer having at least one or two or more types of 3-hydroxyalkanoate units. The 3-hydroxyalkanoate units are preferably represented by the following general formula (1): [-CHR-CH ２ -CO-O-] (1)

[0045] In the general formula (1), R is C ｐ H ２ｐ＋１ where p is an integer of 1 to 15. Examples of R include linear or branched alkyl groups such as methyl, ethyl, propyl, methylpropyl, butyl, isobutyl, t-butyl, pentyl, and hexyl. p is preferably an integer of 1 to 10, and more preferably an integer of 1 to 8.

[0046] The poly(3-hydroxyalkanoate) copolymer (C) preferably contains 3-hydroxyalkanoate units (particularly units represented by general formula (1)) in an amount of 50 mol % or more, more preferably 60 mol % or more, and even more preferably 70 mol % or more of all structural units (monomer units). The poly(3-hydroxyalkanoate) copolymer may contain only two or more types of 3-hydroxyalkanoate units as structural units of the polymer, or may contain other units (e.g., 4-hydroxyalkanoate units) in addition to one or more types of 3-hydroxyalkanoate units.

[0047] The poly(3-hydroxyalkanoate) copolymer (C) is preferably a copolymer containing 3-hydroxybutyrate (hereinafter sometimes referred to as 3HB) units and other hydroxyalkanoate units.

[0048] The other hydroxyalkanoate units may be 3-hydroxyalkanoate units other than 3HB units, or may be hydroxyalkanoate units other than 3-hydroxyalkanoate units (for example, 4-hydroxyalkanoate units). Only one type of other hydroxyalkanoate unit may be included, or two or more types may be included.

[0049] Specific examples of the poly(3-hydroxyalkanoate) copolymer (C) include poly(3-hydroxybutyrate-co-3-hydroxypropionate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (abbreviation: PHBV), poly(3-hydroxybutyrate-co-3-hydroxyvalerate-3-hydroxyhexanoate), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (abbreviation: PHBH), poly(3-hydroxy Examples of suitable poly(3-hydroxybutyrate-co-3-hydroxyheptanoate), poly(3-hydroxybutyrate-co-3-hydroxyoctanoate), poly(3-hydroxybutyrate-co-3-hydroxynonanoate), poly(3-hydroxybutyrate-co-3-hydroxydecanoate), poly(3-hydroxybutyrate-co-3-hydroxyundecanoate), poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (abbreviation: P3HB4HB), etc. In particular, from the viewpoints of productivity and mechanical properties of the resin composition, PHBH or P3HB4HB is preferred, with PHBH being particularly preferred.

[0050] By changing the composition ratio of the repeating units, the melting point and crystallinity of PHBH can be changed, and as a result, physical properties such as Young's modulus and heat resistance can be easily adjusted, and it is possible to impart physical properties between those of polypropylene and polyethylene, making it a particularly useful plastic industrially.

[0051] A specific method for producing PHBH is described in, for example, International Publication No. 2010 / 013483. Commercially available PHBH products include Kaneka Biodegradable Polymer Green Planet (registered trademark) manufactured by Kaneka Corporation.

[0052] The average content ratio of the constituent monomers in PHBH is preferably 3HB / 3HH = 97 to 80 / 3 to 20 (mol % / mol %), and more preferably 3HB / 3HH = 94 to 82 / 6 to 18 (mol % / mol %). When the average content ratio of 3HH in PHBH is 3 mol % or more, the adhesive strength of the laminate can be further improved. Furthermore, when the average content ratio of 3HH is 20 mol % or less, the crystallization rate of PHBH is not too slow, and production is relatively easy.

[0053] The average content ratio of each constituent monomer in PHBH means the molar ratio of 3HB and 3HH contained in PHBH. When PHBH is a mixture of at least two types of PHBH having different content ratios of the constituent monomers, or when PHBH is a mixture containing at least one type of PHBH and PHB, the average content ratio means the molar ratio of each constituent monomer contained in the entire mixture. The average content ratio of the constituent monomers can be determined by a method known to those skilled in the art, for example, the method described in paragraph

[0047] of WO 2013 / 147139, or by NMR measurement.

[0054] As described above, the resin layer (D) may contain, as PHBH, at least two types of PHBH having different content ratios of constituent monomers, or may further contain PHB (a homopolymer of 3-hydroxybutyrate) in addition to at least one type of PHBH.

[0055] When at least two types of PHBH are contained, it is preferable that the PHBH contain a highly crystalline, high-melting-point PHBH having a 3HH content of less than 6 mol % and a low-crystalline, low-melting-point PHBH having a 3HH content of 15 mol % or more.

[0056] The resin layer (D) is preferably a resin layer containing PHBH as a main component. Specifically, the content of PHBH in the resin layer (D) is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, and even more preferably 80 to 100% by weight. The lower limit may be 90% by weight or more, or 95% by weight or more.

[0057] The resin layer (D) may contain only PHBH or only PHBH and PHB as the resin component, or may further contain a resin other than PHBH and PHB in addition to these. The resin other than PHBH and PHB is preferably a biodegradable resin, and specific examples thereof include poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB3HV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (PHB4HB), poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) (PHB3HO), poly(3-hydroxybutyrate-co-3-hydroxyoctadecanoate) (PHB3HOD), poly(3-hydroxybutyrate-co- Examples of suitable resins include poly(3-hydroxyalkanoates) such as poly(3-hydroxydecanoate) (PHB3HD) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate) (PHB3HV3HH); aliphatic polyester resins such as polycaprolactone, polybutylene succinate adipate, polybutylene succinate, and polylactic acid; and aliphatic aromatic polyester resins such as polybutylene adipate terephthalate and polybutylene azelate terephthalate. These resins other than PHBH and PHB may be used alone or in combination of two or more.

[0058] The resin layer (D) may contain additives typically added to resin materials, provided that the effects of the present invention are not impaired. Examples of such additives include inorganic fillers, colorants such as pigments and dyes, odor absorbers such as activated carbon and zeolite, fragrances such as vanillin and dextrin, plasticizers, antioxidants, weather resistance improvers, UV absorbers, crystal nucleating agents, lubricants, release agents, water repellents, antibacterial agents, and sliding properties improvers. These additives may be used alone or in combination of two or more. However, additives are optional components, and the resin layer (D) may not contain these additives. It is preferable to use a lubricant and / or an inorganic filler as additives, as this improves the releasability of the resin layer (D) from the pressure-bonding surface of a cooling roll or the like during lamination.

[0059] Examples of the lubricant include saturated or unsaturated fatty acid amides such as lauric acid amide, myristic acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, oleic acid amide, and erucic acid amide; alkylene fatty acid amides such as methylene bisstearic acid amide and methylene bisstearic acid amide; and aliphatic amide compounds such as pentaerythritol.

[0060] The amount of lubricant in the resin layer (D) is preferably 0.1 to 2 parts by weight, more preferably 0.2 to 1 part by weight, per 100 parts by weight of the total amount of resin components contained in the resin layer (D). By setting the amount to 0.1 part by weight or more, the effect of improving releasability due to the addition of the lubricant can be obtained. If the amount is 2 parts by weight or less, the problem of the lubricant bleeding and adhering to the pressure-bonding surface of a cooling roll or the like during compression bonding can be suppressed, and long-term continuous processing can be performed.

[0061] Examples of the inorganic filler include talc, calcium carbonate, mica, silica, clay, kaolin, titanium oxide, alumina, zeolite, etc. The average particle size of these inorganic fillers is preferably 0.5 μm or more.

[0062] The amount of inorganic filler in the resin layer (D) is preferably 0.5 to 5 parts by weight, more preferably 1 to 3 parts by weight, per 100 parts by weight of the total amount of resin components contained in the resin layer (D). By setting the amount to 0.5 parts by weight or more, the effect of improving releasability due to the incorporation of the inorganic filler can be obtained. When the amount is 5 parts by weight or less, the occurrence of cracks in the resin layer (D) can be suppressed.

[0063] In the laminate according to this embodiment, the thickness of the resin layer (D) is set in the range of 5 μm or more and 100 μm or less. If the thickness is less than 5 μm, the resin may cool too quickly during lamination of the resin layer (D), resulting in a decrease in adhesion to the substrate layer (A) on which the adhesive layer (B) is formed. In addition, cracks are likely to occur in the resin layer (D) when the laminate is processed into a molded product. The lower limit of the thickness is preferably 10 μm or more, more preferably 20 μm or more.

[0064] Furthermore, if the thickness of the resin layer (D) exceeds 100 μm, the resin temperature may become uneven during the formation of the resin layer (D), which may cause uneven thickness or poor appearance due to melt fracture. Furthermore, the laminate may become too hard, resulting in molding defects. The upper limit of the thickness is preferably 80 μm or less, more preferably 60 μm or less.

[0065] [Method for producing laminate] An example of a method for producing the laminate according to this embodiment will be described below. The laminate according to this embodiment can be produced by forming an adhesive layer (B) on at least one surface of a base layer (A) (first step), and then forming a resin layer (D) on the surface of the formed adhesive layer (B) (second step).

[0066] In the first step of forming the adhesive layer (B) on at least one surface of the base layer (A), it is preferable to apply a solution or an aqueous dispersion such as an aqueous slurry containing the components constituting the adhesive layer (B) to one or both surfaces of the base layer (A), and then heat and dry the applied solution to form a film.

[0067] The method for applying the solution or aqueous dispersion to the substrate is not particularly limited, and any known method capable of forming a resin layer on the substrate can be used as appropriate. Specifically, a spraying method, a scattering method, a slit coater method, an air knife coater method, a roll coater method, a bar coater method, a comma coater method, a blade coater method, a screen printing method, a gravure printing method, or the like can be used. Before applying the solution or aqueous dispersion, a step of subjecting the substrate to a surface treatment such as the above-mentioned corona treatment may be carried out.

[0068] The drying treatment after coating can be carried out using a known heating method, such as hot air heating, infrared heating, microwave heating, roll heating, or hot plate heating, which can be used alone or in combination of two or more.

[0069] Next, a second step of forming a resin layer (D) on the surface of the formed adhesive layer (B) is performed. The method of forming the resin layer (D) may be a method of applying a solution or aqueous dispersion containing the components constituting the resin layer (D) to the surface of the adhesive layer (B), heating and drying, and forming a film. However, from the viewpoint of adhesion to the adhesive layer (B), productivity, or quality of suppressing thermal degradation, it is preferable to form the resin layer (D) on the surface of the adhesive layer (B) by extrusion lamination or thermal lamination.

[0070] As the extrusion lamination method, a general extrusion lamination method can be used. Specifically, a molten resin material is extruded into a film shape from a T-shaped die, and is pressed onto the surface of the adhesive layer (B) while being cooled using a cooling roll, and immediately thereafter, the resin material is peeled off from the cooling roll to form the resin layer (D), thereby producing a laminate.

[0071] When the resin layer (D) is formed by the extrusion lamination method, the temperature of the resin immediately after being melt-extruded from the tip of the T-die is preferably equal to or higher than the melting point of the components contained in the resin layer (D) and lower than 165°C.

[0072] As the thermal lamination method, a general thermal lamination method can be used. Specifically, first, a molten resin material is extruded, for example, through a T-shaped die, and cooled using a cooling roll to form a film containing the resin material. Next, the obtained film is pressure-bonded to the surface of the adhesive layer (B) using a heated roll or the like, thereby producing a molded product.

[0073] When the resin layer (D) is formed by the thermal lamination method, it is preferable that the temperature of the resin immediately after being melt-extruded from the tip of the T-die when forming the film constituting the resin layer (D) is equal to or higher than the melting point of the components contained in the resin layer (D) and lower than 165°C.

[0074] For the purpose of improving the adhesion between the resin layer (D) and the base material layer (A) on which the adhesive layer (B) is formed, the surface of the adhesive layer (B) may be subjected to corona treatment, flame treatment, ozone treatment, etc.

[0075] From the viewpoint of adhesiveness and processability (balance between melting and crystallization), it is preferable that the first and second steps are carried out successively.

[0076] [Molded Article] A molded article according to one aspect of the present embodiment includes the laminate described above and has a desired size and shape. The molded article is advantageous in various applications because it is formed from a laminate including a resin layer (D) containing P3HA.

[0077] The molded article is not particularly limited as long as it contains the laminate, and examples thereof include paper, film, sheet, tube, plate, rod, container (e.g., bottle container), bag, part, etc. From the viewpoint of measures against marine pollution, the molded article is preferably a bag or a bottle container.

[0078] The molded article may be the laminate itself, or may be a laminate that has been subjected to secondary processing. By subjecting the laminate to secondary processing, the molded article can be suitably used as various packaging container materials such as shopping bags, various bags, food and confectionery packaging materials, cups, trays, cartons, etc. (in other words, in various fields such as food, cosmetics, electronics, medicine, and pharmaceuticals). Since the molded article includes a resin layer (D) that has high adhesion to the substrate and good heat resistance, it can be more suitably used as a container for holding liquids, particularly as a container for holding hot contents, such as a cup for food and beverages such as instant noodles, instant soup, and coffee, a tray for prepared meals, bento boxes, and microwaveable foods.

[0079] The secondary processing can be carried out in the same manner as conventional resin-laminated paper or coated paper, i.e., using various bag-making machines, filling and packaging machines, etc. Processing can also be carried out using machines such as paper cup forming machines, punching machines, box making machines, etc. In these processing machines, known techniques can be used to bond the laminate, such as heat sealing, impulse sealing, ultrasonic sealing, high-frequency sealing, hot air sealing, and frame sealing.

[0080] The heat-sealing temperature of the laminate varies depending on the bonding method. For example, when a heating-type heat-sealing tester with a seal bar is used, the resin temperature is usually set to 180°C or less, preferably 170°C or less, and more preferably 160°C or less. Within the above range, melting of the resin near the sealed portion can be avoided, and an appropriate resin layer thickness and seal strength can be ensured. Furthermore, when a heating-type heat-sealing tester with a seal bar is used, the lower limit of the resin temperature is usually 100°C or more, preferably 110°C or more, and more preferably 120°C or more. Within the above range, appropriate adhesion at the sealed portion can be ensured.

[0081] The heat-sealing pressure of the laminate varies depending on the bonding method, but for example, when a heat-sealing tester with a seal bar is used, it is usually 0.1 MPa or more, preferably 0.5 MPa or more. Within this range, appropriate bonding at the sealed portion can be ensured. Furthermore, the upper limit of the heat-sealing pressure when a heat-sealing tester with a seal bar is used is usually 1.0 MPa or less, preferably 0.75 MPa or less. Within this range, thinning of the film thickness at the sealed end can be avoided, and seal strength can be ensured.

[0082] In order to improve the physical properties of the molded article, the molded article can be composited with another molded article made of a material different from the molded article (for example, fiber, thread, rope, woven fabric, knitted fabric, nonwoven fabric, paper, film, sheet, tube, plate, rod, container, bag, part, foam, etc.). These materials are also preferably biodegradable.

[0083] The following items are preferred embodiments of the present disclosure, but the present invention is not limited to the following items. [Item 1] A laminate comprising, in this order, a substrate layer (A), an adhesive layer (B), and a resin layer (D) containing a poly(3-hydroxyalkanoate) copolymer (C), wherein the glass transition temperature of the entire resin contained in the adhesive layer (B) is 20°C or higher and lower than 90°C, and the adhesive layer (B) has a basis weight of 0.1 g / m ２ 5.0g / m or more ２a laminate according to claim 1, wherein the adhesive layer (B) contains at least one resin selected from the group consisting of an acrylic resin, a vinyl chloride resin, a styrene-acrylic resin, a styrene-butadiene resin, a styrene-isoprene resin, a polycarbonate resin, a urea resin, a melamine resin, an epoxy resin, a phenolic resin, a urethane resin, a diallyl phthalate resin, and an imine resin; a laminate according to claim 1, wherein the adhesive layer (B) contains at least one of an acrylic resin and a styrene-acrylic resin, and wherein the proportion of styrene units in the entire acrylic resin or styrene-acrylic resin is 0 mol % or more and less than 50 mol %. [Item 4] The laminate according to any one of Items 1 to 3, wherein the adhesive layer (B) contains at least one of an acrylic resin or a styrene-acrylic resin, and wherein a proportion of methyl methacrylate units in the (meth)acrylic units contained in the entire acrylic resin or styrene-acrylic resin is 50 mol% or more and less than 95 mol%. [Item 5] The laminate according to any one of Items 1 to 4, wherein the adhesive layer (B) contains a tackifying resin in an amount of 1 wt% or more and less than 30 wt% of the total weight of the adhesive layer (B). [Item 6] The laminate according to Item 5, wherein the tackifying resin contains at least one resin selected from the group consisting of a rosin-based resin, a terpene-based resin, an ethylene-based resin, a vinyl acetate-based resin, an alkylphenol-formaldehyde-based resin, an alkylphenol-acetylene-based resin, a coumarone-indene-based resin, a styrene-based resin, and a xylene-formaldehyde-based resin. [Item 7] The laminate according to item 5 or 6, wherein the tackifying resin has a weight average molecular weight of 100 or more and less than 5,000. [Item 8] The laminate according to item 1 or 2, wherein the poly(3-hydroxyalkanoate)-based copolymer (C) is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate).[Item 9] A method for producing the laminate according to any one of Items 1 to 8, comprising the steps of forming the adhesive layer (B) on at least one surface of the base layer (A), and forming the resin layer (D) on the surface of the adhesive layer (B) by extrusion lamination or thermal lamination. [Item 10] A method for producing the laminate according to Item 9, wherein, when forming the resin layer (D) by the extrusion lamination method, the resin temperature immediately after being melt-extruded from the tip of a T-die is equal to or higher than the melting point of the components contained in the resin layer (D) and lower than 165°C. [Item 11] A method for producing the laminate according to Item 9, wherein, in the thermal lamination method, a film constituting the resin layer (D) is used, and the film is formed at a resin temperature immediately after being melt-extruded from the tip of a T-die and higher than the melting point of the components contained in the resin layer (D). [Item 12] A molded product comprising the laminate according to any one of Items 1 to 8.

[0084] The present invention will be specifically explained below with reference to examples, but the technical scope of the present invention is not limited to these examples.

[0085] [Production Examples] (Method of Preparing Coating Liquid) Coating Liquid 1: Styrene / methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 10 / 81 / 3 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain Coating Liquid 1. The glass transition temperature of the obtained styrene-acrylic resin was 79°C.

[0086] Coating solution 2: Styrene / methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 5 / 86 / 3 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain coating solution 2. The glass transition temperature of the obtained styrene-acrylic resin was 68°C.

[0087] Coating solution 3: Styrene / methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 10 / 63 / 21 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain coating solution 3. The glass transition temperature of the obtained styrene-acrylic resin was 48°C.

[0088] Coating Solution 4: Styrene / methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 10 / 81 / 3 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain a coating solution. Subsequently, a solution obtained by dissolving rosin ester (RE-650 manufactured by Arakawa Chemical Industries, Ltd., weight average molecular weight 600) in a toluene / isopropanol mixture was mixed with the styrene-acrylic resin and rosin ester so that the rosin ester accounted for 5 wt% of the total weight of the styrene-acrylic resin and rosin ester, to obtain Coating Solution 4. The glass transition temperature of the resulting mixture of styrene-acrylic resin and rosin ester as a whole was 66°C.

[0089] Coating Solution 5: Styrene / methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 10 / 81 / 3 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain a coating solution. Subsequently, a solution obtained by dissolving rosin ester (RE-650 manufactured by Arakawa Chemical Industries, Ltd., weight average molecular weight 600) in a toluene / isopropanol mixture was mixed with the styrene-acrylic resin and rosin ester so that the rosin ester accounted for 15 wt% of the total weight of the styrene-acrylic resin and rosin ester, to obtain Coating Solution 5. The glass transition temperature of the resulting mixture of styrene-acrylic resin and rosin ester as a whole was 62°C.

[0090] Coating Solution 6: Styrene / methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 10 / 81 / 3 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain a coating solution. Subsequently, a solution obtained by dissolving rosin ester (RE-2160 manufactured by Arakawa Chemical Industries, Ltd., weight average molecular weight 2160) in a toluene / isopropanol mixture was mixed with the styrene-acrylic resin and rosin ester so that the rosin ester accounted for 5 wt% of the total weight of the styrene-acrylic resin and rosin ester, to obtain Coating Solution 6. The glass transition temperature of the resulting mixture of styrene-acrylic resin and rosin ester as a whole was 71°C.

[0091] Coating solution 7: Methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 91 / 3 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain coating solution 7. The glass transition temperature of the obtained acrylic resin was 87°C.

[0092] Coating solution 8: Styrene / methyl methacrylate / 2-ethylhexyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 10 / 45 / 39 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain coating solution 8. The glass transition temperature of the obtained styrene-acrylic resin was 16°C.

[0093] Coating solution 9: Styrene / methyl methacrylate / methacrylic acid (all manufactured by Tokyo Chemical Industry Co., Ltd.) were polymerized to a molar ratio of 40 / 54 / 6, and then diluted with a water / isopropanol mixture to a solids concentration of 5%, to obtain coating solution 9. The glass transition temperature of the obtained styrene-acrylic resin was 94°C.

[0094] (PHBH powder) The PHBH powder used was manufactured in accordance with the method described in International Publication No. 2019-142845. The specific formulation is as follows: PHBH powder: PHBH powder having a weight-average molecular weight of 590,000 and a ratio of 3HH to the total of 3HB and 3HH in the PHBH of 15 mol%.

[0095] (Method for producing PHBH pellets) PHBH pellets: The PHBH powder (100 parts by weight) was dry-blended with behenamide (0.5 parts by weight) and pentaerythritol (1.0 part by weight), and the mixture was melt-kneaded and extruded into strands using a twin-screw extruder at a set temperature of 150°C and a screw rotation speed of 100 rpm. The strands were then passed through hot water at 40°C to solidify them, and cut into pellets. The weight-average molecular weight was 550,000.

[0096] <Production of laminate by extrusion lamination method> (Example 1) Basis weight 210 g / m ２ The coating liquid 1 was coated onto an A4 size base paper using a bar coater No. 10, and immediately thereafter, the base paper was placed in a hot air oven heated to 100°C for 30 seconds to dry, thereby forming an adhesive layer (B) on the paper substrate. The basis weight of the obtained adhesive layer (B) was 1.0 g / m ２ Subsequently, the PHBH pellets were fed into a single-screw extruder equipped with a T-die, extruded from the T-die under conditions such that the resin temperature immediately after extrusion was 163°C, and taken up with a cooling roll set at 60°C to form a film having a thickness of 30 µm. The paper substrate with the adhesive layer (B) obtained above and the PHBH film were sandwiched so that the heating roll was in contact with the paper side and the cooling roll was in contact with the PHBH film side, and the conditions were adjusted so that the surface temperature of the PHBH film was 170°C, to obtain a laminate comprising the paper substrate, the adhesive layer (B), and the resin layer (D) in this order.

[0097] (Example 2) A laminate was obtained in the same manner as in Example 1, except that the coating liquid 1 was applied using a bar coater No. 2. The basis weight of the adhesive layer (B) was 0.2 g / m ２ It was.

[0098] (Example 3) A laminate was obtained in the same manner as in Example 1, except that the coating liquid 1 was applied using a bar coater No. 45. The basis weight of the adhesive layer (B) was 4.5 g / m ２ It was.

[0099] Example 4 A laminate was obtained in the same manner as in Example 1, except that the thickness of the PHBH film for the resin layer (D) was changed to 10 μm.

[0100] Example 5 A laminate was obtained in the same manner as in Example 1, except that the thickness of the PHBH film for the resin layer (D) was changed to 70 μm.

[0101] Example 6 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using the coating liquid 2.

[0102] Example 7 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using Coating Liquid 3.

[0103] Example 8 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using Coating Liquid 4.

[0104] Example 9 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using Coating Liquid 5.

[0105] Example 10 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using Coating Liquid 6.

[0106] Example 11 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using Coating Liquid 7.

[0107] Comparative Example 1 A laminate containing a paper substrate and a resin layer (D) without an adhesive layer (B) was obtained in the same manner as in Example 1, except that PHBH was extrusion laminated to a base paper not having an adhesive layer (B).

[0108] Comparative Example 2 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using Coating Liquid 8.

[0109] Comparative Example 3 A laminate was obtained in the same manner as in Example 1, except that the adhesive layer (B) was formed using Coating Liquid 9.

[0110] Comparative Example 4 A laminate was obtained in the same manner as in Example 1, except that the thickness of the PHBH film for the resin layer (D) was changed to 3 μm.

[0111] (Comparative Example 5) A laminate was obtained in the same manner as in Example 1, except that the coating liquid 1 was applied using a bar coater No. 75. The basis weight of the adhesive layer (B) was 7.5 g / m ２ It was.

[0112] [Evaluation Method] Evaluations in the Examples and Comparative Examples were performed using the following methods. (Evaluation of Laminate Strength) Laminate strength tests were performed on the day after extrusion lamination. Specifically, a thin cross-cut was made on the resin layer (D) surface of the obtained laminate with a cutter blade, and Nichiban No. CT-17 tape was firmly attached to the cut area, then gently peeled off by hand to create a starting point. A piece was then cut out to a width of 15 mm, and the peeled laminate layer and paper were gripped with a jig at an angle of 180° to perform a peel strength test. The tensile speed was 200 mm / min. A Shimadzu Autograph EZ-LX (manufactured by Shimadzu Corporation) was used as the peel tester. <Evaluation> ⊚: 4.0 N / 15 mm or more ◯: 3.0 N / 15 mm or more and less than 4.0 N / 15 mm Δ: 2.0 N / 15 mm or more and less than 3.0 N / 15 mm ×: less than 2.0 N / 15 mm If the above evaluation result is ⊚, ○, or Δ, it can be said that the laminate strength is sufficient.

[0113] (Evaluation of drying property) Basis weight 210 g / m ２An A4-sized base paper was coated under the conditions described in the Examples and Comparative Examples to form an adhesive layer (B), and then heated in a hot air oven at 100°C for 30 seconds, removed, and the surface of the adhesive layer (B) was observed. <Evaluation> ○: The surface is not wet and a coating film is sufficiently formed △: The surface is slightly wet, but a coating film is sufficiently formed ×: Puddles are formed on the surface and a coating film is not sufficiently formed If the above evaluation result is ○ or △, drying and coating film formation in a typical papermaking process are possible.

[0114] (Measurement of basis weight of adhesive layer (B)) The papers with adhesive layer (B) obtained in the Examples and Comparative Examples were thoroughly dried for 10 minutes in a hot air oven heated to 100°C, and then aged for one week under conditions of 25°C and 60% humidity. Thereafter, they were cut into 10 cm x 10 cm pieces and their weights were measured. The weight value was subtracted from the weight of the base paper and multiplied by 100 to obtain the basis weight value of the adhesive layer (B).

[0115] (Measurement of the glass transition temperature of the entire resin contained in the adhesive layer (B)) The glass transition temperature of the entire resin contained in the adhesive layer (B) was measured using differential thermal analysis. More specifically, a portion of each coating liquid obtained by the method described in the Production Examples was transferred to a metal container and dried for 30 minutes in a hot air oven set at 100°C. 3 mg of the resulting solid was weighed, and using a differential scanning calorimeter (NETZSCH Polymer 214), the temperature was raised at a rate of 10°C / min in the range of 0°C to 150°C to obtain a temperature dependence curve. The obtained results were further differentiated with respect to temperature to determine the inflection point, and the temperature at that time was taken as the glass transition temperature.

[0116]

[0117] <Results> From Table 1, it can be seen that in each Example, the base material layer (A) and the resin layer (D) containing the poly(3-hydroxyalkanoate) copolymer (C) are bonded with sufficient strength via the adhesive layer (B), and that the drying properties of the adhesive layer (B) after coating are also good. On the other hand, the adhesion properties are insufficient in Comparative Examples 1 to 4, and the drying properties are poor in Comparative Example 5, which shows that the adhesiveness and drying properties are not compatible in each Comparative Example.

[0118] 1. Laminated body 2. Base material layer 3. Adhesive layer (B) 4. Resin layer (D)

Claims

1. A laminate comprising, in this order, a base layer (A), an adhesive layer (B), and a resin layer (D) containing a poly(3-hydroxyalkanoate)-based copolymer (C), The glass transition temperature of the entire resin contained in the adhesive layer (B) is 20° C. or higher and lower than 90° C., The adhesive layer (B) has a basis weight of 0.1 g / m ２ 5.0g / m or more ２ is less than The resin layer (D) has a thickness of 5 μm or more and 100 μm or less, The adhesive layer (B) is a laminate containing at least one resin selected from the group consisting of acrylic resins, vinyl chloride resins, styrene-acrylic resins, styrene-butadiene resins, styrene-isoprene resins, polycarbonate resins, urea resins, melamine resins, epoxy resins, phenolic resins, urethane resins, diallyl phthalate resins, and imine resins.

2. The laminate according to claim 1, wherein the adhesive layer (B) contains at least one of an acrylic resin or a styrene-acrylic resin, and a ratio of styrene units in the entire acrylic resin or the entire styrene-acrylic resin is 0 mol % or more and less than 50 mol %.

3. 3. The laminate according to claim 1, wherein the adhesive layer (B) contains at least one of an acrylic resin or a styrene-acrylic resin, and a ratio of methyl methacrylate units in (meth)acrylic units contained in the entire acrylic resin or the styrene-acrylic resin is 50 mol % or more and less than 95 mol %.

4. The laminate according to claim 1 or 2, wherein the adhesive layer (B) comprises a tackifier resin in an amount of 1 wt % or more and less than 30 wt % of the total weight of the adhesive layer (B).

5. 5. The laminate according to claim 4, wherein the tackifying resin comprises at least one resin selected from the group consisting of rosin-based resins, terpene-based resins, ethylene-based resins, vinyl acetate-based resins, alkylphenol-formaldehyde-based resins, alkylphenol-acetylene-based resins, coumarone-indene-based resins, styrene-based resins, and xylene-formaldehyde-based resins.

6. The laminate according to claim 4 , wherein the tackifier resin has a weight average molecular weight of 100 or more and less than 5,000.

7. 3. The laminate according to claim 1, wherein the poly(3-hydroxyalkanoate)-based copolymer (C) is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate).

8. A method for producing the laminate according to claim 1 or 2, comprising the steps of: A step of forming the adhesive layer (B) on at least one surface of the base layer (A); A method for producing a laminate, comprising the step of forming the resin layer (D) on a surface of the adhesive layer (B) by extrusion lamination or thermal lamination.

9. 9. The method for producing a laminate according to claim 8, wherein, when forming the resin layer (D) by the extrusion lamination method, a resin temperature immediately after melt extrusion from a tip of a T-shaped die is equal to or higher than a melting point of a component contained in the resin layer (D) and lower than 165°C.

10. 9. The method for producing a laminate according to claim 8, wherein in the thermal lamination method, a film constituting the resin layer (D) is used, and the film is a film formed at a resin temperature immediately after melt extrusion from the tip of a T-shaped die of not less than the melting point of a component contained in the resin layer (D) and not more than 165°C.

11. A molded article comprising the laminate according to claim 1 or 2.