Resin composition and laminate having a layer made of said resin composition

Abstract

The purpose of the present invention is to obtain: a resin composition having further improved adhesion to a base material layer when used as an adhesive layer in a laminate; and a laminate having superior adhesive strength between layers including a layer comprising said resin composition.　The present invention relates to a resin composition and a laminate including a layer of said resin composition, the resin composition being characterized by containing 5-70 weight% of a propylene-based polymer (A), 30-95 weight% of a soft propylene-based polymer (B), 0.1-20 weight% of a propylene-based polymer graft-modified with an ethylenically unsaturated monomer (C), 0-20 weight% of polyethylene (D), and 1-30 weight% of an ethylene-α-olefin random copolymer (E) (where the total amount of (A), (B), (C), (D), and (E) is 100 weight%).

Description

[Technical Field]

[0001] The present invention relates to a resin composition that, when used as an adhesive layer in a laminate, has further improved adhesion to a substrate layer, and to a laminate that has excellent adhesive strength between layers containing a layer made of the resin composition. [Background technology]

[0002] Multilayer films made from resins such as ethylene-vinyl acetate copolymer (EVOH), polyamide (PA), polyester (polyethylene terephthalate (PET)), and polypropylene (PP) are used for packaging films to provide gas barrier properties, water vapor barrier properties, and oil resistance. Co-extrusion molding is the most common method for forming multilayer films when all layers are made of thermoplastic resins, as it is easy to form and the resulting multilayer film has excellent interlayer adhesion.

[0003] On the other hand, for applications requiring greater rigidity as a packaging film, biaxially or uniaxially stretched films are used as the base layer (base film), and for applications requiring light-blocking or high barrier properties, aluminum (Al) foil, aluminum vapor-deposited film, or transparent vapor-deposited film made of aluminum oxide or silicon oxide are used as layers in multilayer films.

[0004] One method for obtaining such a biaxially or uniaxially stretched film, or a multilayer film having Al foil, Al vapor-deposited film, or transparent vapor-deposited film, is to apply an adhesive to the bonding surfaces of a layer of a pre-formed stretched film, Al foil, Al vapor-deposited film, etc. and a layer of a heat-sealable film, etc., and then dry-laminate the films to bond them together.

[0005] However, dry lamination has problems such as the toxicity of residual solvents contained in the adhesive and the complicated process, so multi-layering is also being done by extrusion lamination molding, which does not use adhesive.

[0006] On the other hand, extrusion lamination molding is a method in which a molten adhesive resin is extrusion laminated onto the surface of a preformed stretched film, Al foil, Al vapor-deposited film, etc. in order to improve the adhesive strength between layers. However, the adhesion between the two layers is not necessarily high, and the resulting multilayer film may have problems such as peeling at the interface between the substrate layer and the adhesive resin layer.

[0007] As compositions with excellent adhesive strength, there have been proposed a modified polyolefin composition for adhesive use consisting of a propylene polymer, a tackifier, a graft-modified propylene polymer, polyethylene, and an ethylene-α-olefin random copolymer (Patent Document 1), and a resin composition consisting of a propylene resin containing modified polypropylene modified with an unsaturated carboxylic acid or its derivative, a propylene copolymer, an ethylene-α-olefin copolymer, and a polyethylene resin (Patent Document 2).

[0008] However, since the adhesive modified polyolefin composition proposed in Patent Document 1 contains a tackifier, there is a risk of smoke being generated during extrusion molding, and when a multilayer film containing a layer made of the adhesive modified polyolefin composition is used as a packaging material for oily food and drink, there is a risk of the tackifier leaking into the food and drink. Although the resin composition proposed in Patent Document 2 does not contain a tackifier, it still does not have sufficient adhesive strength, and depending on the application, there is a demand for an adhesive resin composition with even greater adhesive strength. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-269688 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-188662 Summary of the Invention [Problem to be solved by the invention]

[0010] An object of the present invention is to provide a resin composition that has further improved adhesion to a substrate layer when used as an adhesive layer in a laminate, and a laminate that has excellent adhesive strength between layers including a layer made of the resin composition. [Means for solving the problem]

[0011] The present invention provides 5 to 70% by weight of the following propylene polymer (A), 95 to 30% by weight of the following soft propylene polymer (B), 0.1 to 20% by weight of a propylene polymer (C) graft-modified with the following ethylenically unsaturated monomer, 0 to 20% by weight of the following polyethylene (D), and 1 to 30% by weight of the following ethylene-α-olefin random copolymer (E): (where the total amount of (A), (B), (C), (D), and (E) is 100% by weight.)

[0012] Propylene polymer (A): A propylene-based polymer having a content of structural units derived from propylene in the range of 80 to 100 mol % and a content of structural units derived from ethylene and / or α-olefins other than propylene in the range of 20 mol % or less (wherein the total of the content of structural units derived from propylene and the content of structural units derived from ethylene and / or α-olefins other than propylene is taken as 100 mol %).

[0013] Density measured according to ASTM D1505 is 0.89 g / cm 3 That's all. Soft propylene polymer (B): A flexible propylene polymer containing 50 to 95 mol % of structural units derived from propylene and 5 to 50 mol % of structural units derived from ethylene and / or α-olefins other than propylene (wherein the total of the content of structural units derived from propylene and the content of structural units derived from ethylene and / or α-olefins other than propylene is 100 mol %).

[0014] Density measured according to ASTM D1505 is 0.89 g / cm 3 is less than. Propylene polymer graft-modified with an ethylenically unsaturated monomer (C): A modified propylene polymer obtained by graft-modifying a propylene polymer (c) having a content of structural units derived from propylene of 50 to 100 mol % and a content of structural units derived from ethylene and / or α-olefins other than propylene of 50 mol % or less (wherein the total content of structural units derived from ethylene and the content of structural units derived from α-olefins other than propylene is defined as 100 mol %) with an ethylenically unsaturated monomer.

[0015] Polyethylene (D): The content of structural units derived from ethylene is 90 to 100 mol %. Density measured according to ASTM D1505: 0.90-0.94 g / cm 3 is in the range.

[0016] Ethylene-α-olefin random copolymer (E): The content of structural units derived from ethylene is in the range of 50 to 88 mol %, and the content of structural units derived from α-olefins is in the range of 12 to 50 mol % (where the total amount of the content of structural units derived from ethylene and the content of structural units derived from α-olefins is 100 mol %).

[0017] Density measured according to ASTM D1505 is 0.90 g / cm 3 is less than. [Effects of the Invention]

[0018] The resin composition of the present invention has good extrusion moldability and excellent adhesive strength to a substrate, and therefore provides a resin composition that can maintain good adhesion to a substrate layer, and a laminate including a layer made of the resin composition. DETAILED DESCRIPTION OF THE INVENTION

[0019] <Propylene polymer (A)> The propylene polymer (A), which is one of the components contained in the resin composition of the present invention, is a propylene polymer having a content of structural units derived from propylene in the range of 80 to 100 mol %, preferably 81 to 99 mol %, and more preferably 82 to 98 mol %, and a content of structural units derived from ethylene and / or α-olefins other than propylene in the range of 0 to 20 mol %, preferably 1 to 19 mol %, and more preferably 2 to 18 mol % (wherein the total of the content of structural units derived from propylene and the content of structural units derived from ethylene and / or α-olefins other than propylene is defined as 100 mol %), and has a density of 0.89 g / cm as measured by ASTM D1505. 3 or more, preferably 0.89 to 0.92 g / cm 3 , more preferably 0.89 to 0.91 g / cm 3 The resin composition of the present invention containing the propylene copolymer (A) having a density within the above range has an excellent balance between flexibility and mechanical strength, and also has high adhesive strength to other layers.

[0020] Specific examples of the propylene polymer (A) according to the present invention include propylene homopolymers and copolymers of propylene with ethylene and / or an α-olefin having 4 to 20 carbon atoms.

[0021] Examples of the α-olefin having 4 to 20 carbon atoms include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. As the at least one olefin selected from ethylene and α-olefins, particularly ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene are preferred, and the ethylene and α-olefin may be used singly or in combination of two or more kinds, for example, ethylene and 1-butene.

[0022] The copolymer of propylene with these α-olefins may be a random copolymer or a block copolymer. The structural units derived from these α-olefins may be contained in the copolymer of α-olefin and propylene in a proportion of 0 to 20 mol %, preferably 1 to 19 mol %.

[0023] The propylene polymer (A) according to the present invention preferably satisfies the following requirement (a). (a) The melting point (Tm) measured using a differential scanning calorimeter (DSC) is 120°C or higher, more preferably in the range of 120 to 170°C, and even more preferably 130 to 165°C.

[0024] The propylene polymer (A) according to the present invention has a melt flow rate (MFR) measured in accordance with ASTM D 1238 at 230°C under a load of 2.16 kg, which is usually in the range of 0.01 to 1000 g / 10 min, preferably 0.05 to 100 g / 10 min.

[0025] Examples of the propylene polymer (A) according to the present invention include propylene homopolymers having excellent heat resistance, block copolymers having an excellent balance between heat resistance and flexibility, such as block copolymers (block PPs) typically containing 3 to 30 mass% of an n-decane eluted rubber component, and random copolymers (random PPs) having an excellent balance between flexibility and transparency, such as random copolymers (random PPs) having a melting point (Tm) measured using a differential scanning calorimeter (DSC) of 120°C or higher, preferably 130 to 150°C. These may be appropriately selected to obtain the desired physical properties, or two or more types of propylene polymers (A) having different melting points or rigidities may be used in combination.

[0026] The propylene polymer (A) according to the present invention can be produced by polymerizing propylene or copolymerizing propylene with another α-olefin using, for example, a Ziegler catalyst system comprising a solid catalyst component containing magnesium, titanium, a halogen, and an electron donor as essential components, an organoaluminum compound, and an electron donor, or a metallocene catalyst system using a metallocene compound as one of the catalyst components.

[0027] <Soft propylene polymer (B)> The flexible propylene polymer (B), which is one of the components contained in the resin composition of the present invention, is a flexible propylene polymer containing structural units derived from propylene in a range of 50 to 95 mol %, preferably 60 to 94 mol %, and more preferably 70 to 93 mol %, and containing structural units derived from an α-olefin other than ethylene and / or propylene, preferably an α-olefin having 4 to 20 carbon atoms, in a range of 5 to 50 mol %, preferably 6 to 40 mol %, and more preferably 7 to 30 mol % (wherein the total of the structural units derived from propylene and the structural units derived from ethylene and / or α-olefin other than propylene is defined as 100 mol %), and has a density of 0.89 g / cm as measured by ASTM D1505. 3 less than 0.85 to 0.89 g / cm 3 , more preferably 0.86 to 0.88 g / cm 3The resin composition of the present invention containing the soft propylene polymer (B) having a density within the above range has an excellent balance between flexibility and mechanical strength, and also has high adhesive strength to other layers.

[0028] Examples of the α-olefin having 4 to 20 carbon atoms include 3-methyl-1-butene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene.

[0029] As the at least one olefin selected from ethylene and α-olefins, particularly ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene are preferred, and the ethylene and α-olefins may be used singly or in combination of two or more, for example, ethylene and 1-butene.

[0030] The flexible propylene polymer (B) according to the present invention preferably satisfies the following requirement (b). (b) The melting point (Tm) measured using a differential scanning calorimeter (DSC) is 110°C or lower, preferably in the range of 40 to 110°C, more preferably 45 to 108°C, or no melting point is observed.

[0031] Here, "no melting point is observed" means that no crystalline melting peak having a heat of crystalline fusion of 1 J / g or more is observed in the range of -150 to 200°C in differential scanning calorimetry. If the melting point (Tm) satisfies the above conditions, it is preferable in terms of compatibility with the propylene-based polymer and transparency.

[0032] The details of the melting point measurement conditions are as described in the Examples section below. The flexible propylene polymer (B) according to the present invention has an MFR measured in accordance with ASTM D1238 at 230° C. under a load of 2.16 kg of usually 0.01 to 100 g / 10 min, preferably 0.01 to 30 g / 10 min.

[0033] The flexible propylene polymer (B) according to the present invention preferably has a single glass transition temperature, and the glass transition temperature (Tg) measured using a differential scanning calorimeter (DSC) is usually in the range of -50 to 10°C, preferably -45 to 0°C, and more preferably -40 to 0°C.

[0034] When the soft propylene polymer (B) has a glass transition temperature (Tg) within the above range, the resulting packaging material containing the resin composition is preferably excellent in cold resistance and low-temperature properties as well as exhibits stress absorption properties.

[0035] <Propylene polymer (C) graft-modified with ethylenically unsaturated monomer> The resin composition of the present invention is a propylene polymer (C) graft-modified with an ethylenically unsaturated monomer (hereinafter, sometimes abbreviated as "modified propylene polymer (C)").

[0036] The modified propylene polymer (C) according to the present invention is a modified propylene polymer obtained by graft-modifying, with an ethylenically unsaturated monomer, a propylene polymer (c) having a content of structural units derived from propylene of 50 to 100 mol % and a content of structural units derived from ethylene and / or α-olefins other than propylene of 50 mol % or less (wherein the total content of structural units derived from ethylene and the content of structural units derived from α-olefins other than propylene is defined as 100 mol %).

[0037] The propylene polymer (c) according to the present invention is a propylene homopolymer and / or a propylene-α-olefin copolymer. The α-olefin is not limited, but preferably includes ethylene and α-olefins having 4 to 20 carbon atoms, and these α-olefins may be used alone or in combination of two or more. Preferred α-olefins are ethylene and α-olefins having 4 to 10 carbon atoms, and among these, ethylene and α-olefins having 4 to 8 carbon atoms are particularly preferred. Here, the content of structural units derived from propylene in the propylene-α-olefin copolymer is in the range of 50 to 100 mol %, preferably 60 to 100 mol %, more preferably 70 to 100 mol %, and the content of structural units derived from ethylene and / or α-olefins other than propylene is in the range of 0 to 50 mol %, preferably 0 to 40 mol %, more preferably 0 to 30 mol % (however, the total amount of the content of structural units derived from ethylene and the content of structural units derived from ethylene and / or α-olefins other than propylene is 100 mol %).

[0038] The method for producing the propylene polymer (c) according to the present invention is not particularly limited, and examples thereof include well-known methods using well-known catalysts such as Ziegler-Natta catalysts and metallocene catalysts.

[0039] Examples of the ethylenically unsaturated monomer, preferably an unsaturated carboxylic acid and / or a derivative thereof, to be graft-modified onto the propylene polymer (c) according to the present invention include an unsaturated compound having one or more carboxylic acid groups, an ester of a compound having a carboxylic acid group with an alkyl alcohol, and an unsaturated compound having one or more carboxylic acid anhydride groups.

[0040] Examples of unsaturated groups contained in the unsaturated compound include vinyl groups, vinylene groups, and unsaturated cyclic hydrocarbon groups. The unsaturated carboxylic acids and / or their derivatives can be used singly or in combination of two or more. Among these ethylenically unsaturated monomers, unsaturated dicarboxylic acids or their acid anhydrides are preferred, with maleic acid, nadic acid, and their acid anhydrides being particularly preferred.

[0041] The method for grafting the propylene polymer (c) according to the present invention with an ethylenically unsaturated monomer is not particularly limited, and any conventionally known graft polymerization method can be employed, such as a solution method, a melt-kneading method, etc. For example, there is a method in which the propylene polymer (c) is melted, and an ethylenically unsaturated monomer is added to carry out a graft reaction, or a method in which the propylene polymer (c) is dissolved in a solvent to form a solution, and an ethylenically unsaturated monomer is added to the solution to carry out a graft reaction.

[0042] The modified propylene polymer (C) according to the present invention preferably has a content of structural units derived from ethylenically unsaturated monomers of 0.01 to 5 mass % or 0.01 to 5.0 mass %, more preferably 0.05 to 3.5 mass %, calculated as structural units derived from maleic anhydride.

[0043] A resin composition containing the modified propylene polymer (C) in which the amount of structural units derived from an ethylenically unsaturated monomer falls within the above range can provide a resin composition that is excellent in balance between moldability and adhesiveness.

[0044] <Polyethylene (D)> The polyethylene (D), which is one of the components contained in the resin composition of the present invention, has a content of structural units derived from ethylene of 90 to 100 mol % and a density measured according to ASTM D1505 of 0.90 to 0.94 g / cm 3 , preferably 0.91 to 0.93 g / cm 3 is in the range.

[0045] The polyethylene (D) according to the present invention is an ethylene homopolymer or a copolymer of ethylene and at least one α-olefin selected from α-olefins having 3 to 20 carbon atoms, which are manufactured and sold as high-pressure low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), or high-density polyethylene (HDPE), and is an ethylene-based polymer mainly composed of ethylene.

[0046] Examples of the α-olefin having 3 to 20 carbon atoms include propylene, 3-methyl-1-butene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. These α-olefins may be used alone or in combination.

[0047] The polyethylene (D) according to the present invention has an MFR, measured in accordance with ASTM D 1238 at 190°C under a load of 2.16 kg, of usually 0.1 to 10 g / 10 min, preferably 0.5 to 8 g / 10 min, and more preferably 1 to 6 g / 10 min. The resin composition of the present invention containing polyethylene (D) having an MFR in the above range has an excellent balance between flexibility and mechanical strength, and also has high adhesive strength to other layers.

[0048] The method for producing the polyethylene (D) according to the present invention is not particularly limited, and it can be produced by a known method using a known catalyst such as a high-pressure method, a Ziegler-Natta catalyst, or a metallocene catalyst. Furthermore, there are no particular limitations on the stereoregularity or molecular weight, so long as it satisfies moldability and has strength sufficient for use when formed into a molded article. Commercially available resins can also be used as they are.

[0049] <Ethylene-α-olefin random copolymer (E)> The ethylene-α-olefin random copolymer (E), which is one of the components contained in the resin composition of the present invention, has a content of structural units derived from ethylene in the range of 50 to 88 mol % and a content of structural units derived from α-olefin in the range of 12 to 50 mol % (wherein the total content of structural units derived from ethylene and the content of structural units derived from α-olefin is taken as 100 mol %), and has a density of 0.90 g / cm as measured by ASTM D1505. 3 is less than.

[0050] The α-olefin to be copolymerized with ethylene is preferably an α-olefin having 3 to 20 carbon atoms, and specific examples thereof include propylene, 3-methyl-1-butene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. These α-olefins may be used alone or in combination of two or more.

[0051] The ethylene-α-olefin random copolymer (E) according to the present invention has a content of structural units derived from ethylene in the range of preferably 50 to 88 mol %, more preferably 60 to 86 mol %, and even more preferably 60 to 85 mol %, and a content of structural units derived from α-olefin in the range of preferably 12 to 50 mol %, more preferably 14 to 40 mol %, and even more preferably 15 to 40 mol %.

[0052] The ethylene-α-olefin random copolymer (E) according to the present invention preferably has a density of 0.85 to 0.90 g / cm 3 , more preferably 0.86 to 0.90 g / cm 3 is in the range.

[0053] The ethylene-α-olefin random copolymer (E) according to the present invention typically has an MFR of 0.1 to 100 g / 10 min, preferably 0.5 to 50 g / 10 min, measured at 190°C under a load of 2.16 kg in accordance with ASTM D 1238. The resin composition of the present invention containing the ethylene-α-olefin random copolymer (E) having an MFR in the above range has an excellent balance between flexibility and mechanical strength, and also has high adhesive strength to other layers.

[0054] The ethylene-α-olefin random copolymer (E) according to the present invention preferably satisfies the following requirement (e): (e) The melting point (Tm) measured using a differential scanning calorimeter (DSC) is 110° C. or lower, preferably in the range of 40 to 85° C., more preferably 40 to 60° C., or no melting point is observed.

[0055] Here, "no melting point is observed" means that no crystalline melting peak having a heat of crystalline fusion of 1 J / g or more is observed in the range of -150 to 200°C in differential scanning calorimetry. The resin composition of the present invention containing the ethylene-α-olefin random copolymer (E) whose melting point (Tm) satisfies the above condition has an excellent balance between flexibility and mechanical strength, and also has high adhesive strength to other layers.

[0056] The details of the melting point measurement conditions are as described in the Examples section below. The method for producing the ethylene-α-olefin random copolymer (E) according to the present invention is not particularly limited, and examples thereof include well-known methods using well-known catalysts such as Ziegler-Natta catalysts and metallocene catalysts.

[0057] 《Resin composition》 The resin composition of the present invention comprises: The propylene polymer (A) is 5 to 70% by weight, preferably 5 to 50% by weight, more preferably 5 to 30% by weight, 30 to 95% by weight, preferably 35 to 95% by weight, more preferably 40 to 95% by weight of the soft propylene polymer (B), 0.1 to 20% by weight, preferably 0.5 to 15% by weight, more preferably 1 to 10% by weight of the propylene polymer (C) graft-modified with the ethylenically unsaturated monomer, The polyethylene (D) is present in an amount of 0 to 20% by weight, preferably 1 to 20% by weight, more preferably 1 to 19% by weight, even more preferably 2 to 18% by weight, particularly preferably 10 to 18% by weight, 1 to 30% by weight, preferably 2 to 29% by weight, more preferably 3 to 28% by weight of the ethylene-α-olefin random copolymer (E) (where the total amount of (A), (B), (C), (D), and (E) is 100% by weight.)

[0058] The resin composition of the present invention contains the above-mentioned components (A), (B), (C), and (E) in the above ranges, so that a resin composition having an excellent balance between moldability and adhesiveness can be obtained.

[0059] The resin composition of the present invention contains the above-mentioned components (A), (B), (C), (D) and (E) in the above ranges, so that a resin composition having an excellent balance between moldability and adhesiveness can be obtained.

[0060] The resin composition of the present invention has excellent adhesiveness to other materials and can therefore also be used as a resin composition for adhesives, for example, a resin composition for hot melt adhesives. The resin composition of the present invention has an MFR measured in accordance with ASTM D1238 at 230°C under a load of 2.16 kg, generally in the range of 1 to 50 g / 10 min, preferably 5 to 30 g / 10 min. A resin composition having an MFR within the above range has an excellent balance between moldability and adhesiveness.

[0061] The resin composition of the present invention may contain other thermoplastic resins such as polyolefin-based resins, and resin additives (for example, stabilizers such as heat stabilizers and weather stabilizers, crosslinking agents, crosslinking aids, antistatic agents, slip agents, antiblocking agents, antifogging agents, lubricants, dyes, pigments, fillers, mineral oil-based softeners, petroleum resins, waxes, etc.), as long as the addition does not impair the object of the present invention.

[0062] However, the resin composition of the present invention preferably contains 0% by weight or more and less than 1% by weight of tackifier, and more preferably 0% by weight. Here, a tackifier content of 0% by weight means that no tackifier is contained.

[0063] Examples of such tackifiers include aliphatic hydrocarbon resins made primarily from C4 fractions, C5 fractions, or mixtures thereof obtained by cracking petroleum, naphtha, etc., or any of these fractions, such as isoprene and 1,3-pentadiene in the C5 fraction; aromatic hydrocarbon resins made primarily from styrene derivatives and indenes in the C9 fraction obtained by cracking petroleum, naphtha, etc.; aliphatic / aromatic copolymer hydrocarbon resins obtained by copolymerizing any fraction of the C4 / C5 fraction with the C9 fraction; alicyclic hydrocarbon resins obtained by hydrogenating aromatic hydrocarbon resins; synthetic terpene hydrocarbon resins having a structure containing aliphatic, alicyclic, and aromatic groups; terpene hydrocarbon resins made from α,β-pinene in turpentine oil; coumarone-indene hydrocarbon resins made from indene and styrenes in coal tar naphtha; low-molecular-weight styrene resins; and rosin hydrocarbon resins.

[0064] <<Method for producing resin composition>> The olefin polymer composition of the present invention can be produced by various known methods, for example, by melt-kneading or dry-blending the propylene polymer (A), the soft propylene polymer (B), the propylene polymer graft-modified with an ethylenically unsaturated monomer (C), the polyethylene (D), and the ethylene-α-olefin random copolymer (E) in amounts within the above-mentioned ranges.

[0065] <<Laminate>> The laminate of the present invention is a laminate including a layer made of the resin composition of the present invention, for example, a laminate in which a layer made of the resin composition of the present invention is laminated on at least one surface of a base layer.

[0066] The laminate of the present invention is not particularly limited in the form of the substrate layer, and may be in any form, such as a film, a container, or a tube. The substrate used in the present invention can be any polymer capable of forming a film, or paper, aluminum foil, cellophane, etc. Examples of such polymers include olefin copolymers such as high-density polyethylene, medium-density and low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer, ionomer, polypropylene, poly-1-butene, and poly-4-methyl-1-pentene; vinyl copolymers such as polyvinyl chloride, polyvinylidene chloride, polystyrene, polyacrylate, and polyacrylonitrile; polyamides such as nylon 6, nylon 66, nylon 7, nylon 10, nylon 1, nylon 12, nylon 610, and polymetaxylene adipamide; polyesters such as polyethylene terephthalate, polyethylene terephthalate / isophthalate, and polybutylene terephthalate; polyvinyl alcohol, ethylene-vinyl alcohol copolymer, and polycarbonate.

[0067] The substrate according to the present invention preferably has an inorganic compound vapor-deposited layer or a metal layer on at least one side of the substrate, since this provides the resulting laminate with superior appearance and gas barrier properties. When a substrate having an inorganic vapor deposition layer or a metal layer on at least one side is used, the layer of the resin composition of the present invention may be in contact with the inorganic vapor deposition layer or metal layer of the substrate (i.e., the surface of the substrate layer on which the resin composition is laminated may have an inorganic vapor deposition layer or metal layer), or may be in contact with the opposite side.However, when the inorganic vapor deposition layer is arranged on the outside, one or more protective layers may be laminated thereon.

[0068] The protective layer may be made of a polymer or paper that can be used for the base layer, aluminum foil, cellophane, or the like, and for example, polyethylene terephthalate may be used.

[0069] The substrate of the present invention can be appropriately selected depending on the purpose. For example, when the packaged item is a food that is prone to corrosion, a resin with excellent transparency, rigidity, and gas permeation resistance, such as polyamide, polyvinylidene chloride, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, or polyester, is selected. For packaging of confectionery or textiles, a polypropylene with excellent transparency, rigidity, and water permeation resistance can be selected as the outer layer. Furthermore, if the substrate is a polymer, it may be uniaxially or biaxially stretched. Furthermore, the substrate may include a printed surface or a primer.

[0070] Inorganic compounds used for inorganic compound vapor deposition include metals such as aluminum (aluminum), gold, and silver, and oxides such as aluminum oxide (aluminum oxide), silicon oxide, magnesium oxide, and indium-zinc oxide, but aluminum, aluminum oxide, and silicon oxide are preferred in terms of cost and gas barrier properties.

[0071] There are no particular restrictions on the thickness of the vapor-deposited layer, but it is preferably in the range of 50 to 5000 Å, more preferably 300 to 2000 Å. Examples of methods for obtaining a laminate using the resin composition of the present invention include a method in which the resin composition of the present invention and one or more other resins that constitute the laminate are melted in separate extruders and then fed separately into a two- or three-layer die to be coextrusion laminated onto the substrate, with the resin composition of the present invention facing the substrate side, or a so-called sandwich lamination method in which the composition is melt-extruded between two layers of preformed substrates. The die used here is a so-called flat die, and may be either a single-manifold type using a black box or a multi-manifold type.

[0072] The thickness of the layer using the resin composition of the present invention is not particularly limited, but is preferably in the range of 0.1 to 1000 μm. The resin composition of the present invention exhibits excellent adhesive properties to metal layers and resins, and therefore the laminate of the present invention can be suitably used for packaging food such as snacks and dry foods. [Example]

[0073] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples. The polymers used in the examples and comparative examples are shown below. [Propylene polymer (A)] Propylene-ethylene-1-butene random copolymer (PP) was used as the propylene polymer (A).

[0074] Propylene content = 87 mol%, ethylene content = 7 mol%, 1-butene content = 6 mol%, MFR (230°C, 2.16 kg load) = 7 g / 10 min, density = 0.90 g / cm 3 , melting point (Tm) = 141°C. [Soft propylene polymer (B)] Propylene-ethylene random copolymer (PER) was used as the flexible propylene polymer (B).

[0075] Propylene content = 79 mol%, ethylene content = 21 mol%, MFR (230°C, 2.16 kg load) = 20 g / 10 min, density = 0.86 g / cm 3 , melting point (Tm) = 109°C, glass transition temperature (Tg) = -33°C. [Propylene polymer (C) graft-modified with ethylenically unsaturated monomer] As the modified propylene polymer (C), a maleic anhydride modified propylene homopolymer (modified PP) was used.

[0076] MFR (230℃, 2.16kg load) = 100g / 10 minutes, density = 0.90g / cm 3 , maleic anhydride graft modification amount=3.0 mass %. [Polyethylene (D)] As the polyethylene (D), the following high-pressure low-density polyethylene was used.

[0077] High-pressure low-density polyethylene (LDPE-1) MFR (190℃, 2.16kg load) = 4g / 10 minutes, density = 0.92g / cm 3 . High-pressure low-density polyethylene (LDPE-2) MFR (190℃, 2.16kg load) = 7g / 10 minutes, density = 0.92g / cm 3 . [Ethylene-α-olefin random copolymer (E)] The following ethylene-α-olefin random copolymers were used:

[0078] Ethylene-1-butene copolymer (EBR-1) MFR (230℃, 2.16kg load) = 7g / 10 minutes, density = 0.87g / cm 3 , ethylene content = 85 mol %, 1-butene content = 15 mol %.

[0079] Ethylene-1-butene copolymer (EBR-2) MFR (230℃, 2.16kg load) = 70g / 10 minutes, density = 0.87g / cm 3 , ethylene content = 85 mol %, 1-butene content = 15 mol %.

[0080] Ethylene-1-butene copolymer (EBR-3) MFR (230℃, 2.16kg load) = 7g / 10 minutes, density = 0.89g / cm 3 , ethylene content = 90 mol % (82 wt %), 1-butene content = 10 mol % (18 wt %).

[0081] Ethylene-Propylene Copolymer (EPR) MFR (230℃, 2.16kg load) = 8g / 10 minutes, density = 0.87g / cm 3 , ethylene content = 80 mol %, propylene content = 20 mol %.

[0082] The physical properties of the polymers and resin compositions used in the examples and comparative examples were measured by the following methods. [Method of measuring physical properties] <Melt flow rate (MFR)> The MFR was measured according to ASTM D1238. The propylene polymer (A), flexible propylene polymer (B), propylene polymer graft-modified with an ethylenically unsaturated monomer (C), ethylene-α-olefin copolymer (E), and resin composition were measured at 230°C under a load of 2.16 kg, and the polyethylene (D) was measured at 190°C under a load of 2.16 kg.

[0083] <density> The density was measured in accordance with ASTM D1505 (density gradient tube method). <Polymer composition> The content of structural units derived from ethylene and structural units derived from α-olefin in the copolymer is 13 C-NMR was performed using the following equipment and conditions.

[0084] The ethylene and α-olefin contents were quantified using a JECX400P nuclear magnetic resonance spectrometer manufactured by JEOL Ltd., using a mixed solvent of heavy orthodichlorobenzene / heavy benzene (80 / 20% by volume) as the solvent, with a sample concentration of 60 mg / 0.6 mL, a measurement temperature of 120 °C, and observation nuclei of 13 The measurements were performed under the conditions of C (100 MHz), sequence as single pulse proton decoupling, pulse width of 4.62 μsec (45° pulse), repetition time of 5.5 sec, number of accumulations of 8000, and chemical shift reference value of 29.73 ppm.

[0085] <Amount of structural units derived from ethylenically unsaturated monomers (graft modification amount)> The amount of structural units derived from ethylenically unsaturated monomers (graft modification amount) was determined by measuring the peak derived from the structural units (1790 cm when maleic anhydride was used) using an infrared absorption analyzer. -1 The intensity of the chromatogram was measured and quantified using a calibration curve prepared in advance.

[0086] <Melting point (Tm), glass transition temperature (Tg)> The Tm and Tg of the raw materials of the adhesive below were measured by differential scanning calorimetry (DSC) using the method described below.

[0087] Approximately 5 mg of the sample was sealed in an aluminum pan, and using a Seiko Instruments Inc. DSCRDC220, the sample was heated from room temperature to 200°C at a rate of 10°C / min, held at 200°C for 5 minutes, then cooled from 200°C to -100°C at a rate of 10°C / min, held at -100°C for a further 5 minutes, and then heated to 200°C at a rate of 10°C / min. The melting point (Tm) and glass transition temperature (Tg) were determined from the endothermic curve.

[0088] When multiple peaks were detected during the measurement, the peak temperature detected on the highest temperature side was defined as the melting point (Tm). [ refer to Example 1] <Production of Resin Composition> A resin composition was obtained by melt-kneading 26% by weight of a propylene polymer (A) PP, 45% by weight of a flexible propylene polymer (B) PER, 4% by weight of a propylene polymer (C) modified PP grafted with an ethylenically unsaturated monomer, and 25% by weight of an ethylene-α-olefin random copolymer (E) EBR-1 in a single-screw extruder at 230°C. The resulting resin composition had an MFR of 14 g / 10 min and a density of 0.88 g / cm. 3 It was.

[0089] <Production of laminate> Commercially available polypropylene (F329RA manufactured by Prime Polymer Co., Ltd., MFR (230 ° C): 27 g / 10 min) and the above resin composition were co-extruded at 230 ° C into a T-die with a die temperature of 310 ° C using a co-extrusion film molding machine with a screw diameter of 50 mm and an effective length L / D = 28. The extruded polypropylene and resin composition were laminated in the feed block of the T-die so that the polypropylene was the outer layer and the resin composition was the inner layer. The film-like laminate, which was about 40 μm thick and had both an outer layer and an inner layer of 20 μm, was brought into contact in a molten state with the aluminum side of an aluminum PET film (aluminum layer: 20 μm) / polyethylene terephthalate layer: 12 μm) (extrusion lamination), and cooled with a chill roll equipped with a pinch roll. A multilayer film for adhesive strength evaluation (polypropylene layer: 20 μm / resin composition layer: 20 μm / aluminum layer: 20 μm / polyethylene terephthalate layer 12 μm) was obtained.

[0090] [Moldability] During the formation of the laminate by the above co-extrusion coating molding, the presence or absence of edge vibration at the end of the molten film was evaluated.

[0091] [Interlayer adhesion strength of multilayer film] The resulting laminate consisting of the multilayer film was stored at room temperature for one week, and then cut into 15 mm widths. The interlayer adhesive strength between the aluminum layer and the resin composition layer was evaluated by the T-peel method. The evaluation was performed using a tensile tester in an atmosphere of 23°C. The crosshead speed was 300 mm / min.

[0092] The physical properties of the resulting resin composition and laminate are shown in Table 1. [ Reference Examples 2, 9, Example 3 ~ 8 ] Except for the changes in the formulation shown in Table 1, refer to The adhesive was prepared as in Example 1. refer to A laminate was produced in the same manner as in Example 1. The physical properties of the resulting adhesive and laminate are shown in Table 1.

[0093] [Comparative Examples 1 to 6] Except for the changes in the formulation shown in Table 1, refer to The adhesive was prepared as in Example 1. refer to A laminate was produced in the same manner as in Example 1.

[0094] The physical properties of the resulting resin composition and laminate are shown in Table 2.

[0095] [Table 1]

[0096] [Table 2] [Example 10] Instead of aluminum PET film, aluminum vapor-deposited PET film (12 μm) was used as the adherend, and the formulation was changed to that shown in Table 2. refer to A resin composition was prepared in the same manner as in Example 1. refer to A laminate was produced in the same manner as in Example 1.

[0097] The physical properties of the resulting resin composition and laminate are shown in Table 3.

[0098] [Table 3]

Claims

1. 5 to 30% by weight of the following propylene polymer (A), 40 to 95% by weight of the following soft propylene polymer (B), 0.1 to 20% by weight of a propylene polymer (C) graft-modified with the following ethylenically unsaturated monomer, 1 to 20% by weight of the following polyethylene (D), and 1 to 30% by weight of the following ethylene / α-olefin random copolymer (E): (wherein the total amount of (A), (B), (C), (D), and (E) is 100% by weight). Propylene polymer (A): A propylene-based polymer having a content of structural units derived from propylene in the range of 80 to 100 mol % and a content of structural units derived from ethylene and / or an α-olefin other than propylene in the range of 20 mol % or less (where the total of the content of structural units derived from propylene and the content of structural units derived from ethylene and / or an α-olefin other than propylene is taken as 100 mol %). Density measured by ASTM D1505 is 0.89 g / cm ３ That's all. Soft propylene polymer (B): A flexible propylene-based polymer containing 50 to 95 mol % of structural units derived from propylene and 5 to 50 mol % of structural units derived from ethylene and / or an α-olefin other than propylene (where the total content of structural units derived from propylene and the content of structural units derived from ethylene and / or an α-olefin other than propylene is taken as 100 mol %). Density measured by ASTM D1505 is 0.89 g / cm ３ is less than. Propylene polymer (C) graft-modified with an ethylenically unsaturated monomer: A modified propylene polymer obtained by graft-modifying a propylene polymer (c) having a content of structural units derived from propylene of 50 to 100 mol % and a content of structural units derived from ethylene and / or an α-olefin other than propylene of 50 mol % or less (wherein the total content of structural units derived from ethylene and the content of structural units derived from an α-olefin other than propylene is defined as 100 mol %) with an ethylenically unsaturated monomer. Polyethylene (D): The content of structural units derived from ethylene is 90 to 100 mol %. Density measured by ASTM D1505 is 0.90 to 0.94 g / cm ３ is in the range. Ethylene / α-olefin random copolymer (E): The content of structural units derived from ethylene is in the range of 50 to 88 mol %, and the content of structural units derived from α-olefin is in the range of 12 to 50 mol % (where the total amount of the content of structural units derived from ethylene and the content of structural units derived from α-olefin is taken as 100 mol %). Density measured by ASTM D1505 is 0.90 g / cm ３ is less than.

2. 2. The resin composition according to claim 1, wherein at least a portion of the propylene polymer (C) graft-modified with an ethylenically unsaturated monomer is graft-modified with an unsaturated carboxylic acid or a derivative thereof.

3. The resin composition according to claim 1 or 2, wherein the ethylene / α-olefin random copolymer (E) comprises an α-olefin having 3 to 8 carbon atoms.

4. 4. The resin composition according to claim 1, wherein the flexible propylene polymer (B) is a propylene-ethylene copolymer.

5. The resin composition according to any one of claims 1 to 4, wherein the propylene-based polymer (C) graft-modified with an ethylenically unsaturated monomer has a structural unit derived from the ethylenically unsaturated monomer in an amount of 0.01 to 5.0 mass%.

6. The resin composition according to any one of claims 1 to 5, wherein the propylene polymer (C) graft-modified with an ethylenically unsaturated monomer is a propylene polymer (C) graft-modified with maleic anhydride.

7. The resin composition according to any one of claims 1 to 6, which is a resin composition containing no tackifier.

8. The resin composition according to any one of claims 1 to 7, which is used as an adhesive.

9. A laminate comprising a layer made of the resin composition according to any one of claims 1 to 7.

10. The laminate according to claim 9, wherein a layer made of the resin composition is laminated on at least one surface of a substrate layer.

11. The laminate according to claim 10, wherein the substrate layer has an inorganic compound vapor-deposited layer or a metal layer on the surface of the substrate layer on which the resin composition is laminated.

12. The laminate according to claim 11, wherein the inorganic compound vapor-deposited layer is an aluminum vapor-deposited layer.

13. The laminate according to claim 11, wherein the metal layer is an aluminum layer.

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